Exploring the Least Studied Australian Eucalypt Genera: Corymbia and Angophora for Phytochemicals with Anticancer Activity against Pancreatic Malignancies

While the pharmacological and toxicological properties of eucalypts are well known in indigenous Australian medicinal practice, investigations of the bioactivity of eucalypt extracts against high mortality diseases such as pancreatic cancer in Western medicine have to date been limited, particularly amongst the genera Corymbia and Angophora. Four Angophora and Corymbia species were evaluated for their phytochemical profile and efficacy against both primary and secondary pancreatic cancer cell lines. The aqueous leaf extract of Angophora hispida exhibited statistically higher total phenolic content (107.85 ± 1.46 mg of gallic acid equiv. per g) and total flavonoid content (57.96 ± 1.93 mg rutin equiv. per g) and antioxidant capacity compared to the other tested eucalypts (P < 0.05). Both A. hispida and A. floribunda aqueous extracts showed statistically similar saponin contents. Angophora floribunda extract exerted significantly greater cell growth inhibition of 77.91 ± 4.93% followed by A. hispida with 62.04 ± 7.47% (P < 0.05) at 100 μg/ml in MIA PaCa‐2 cells with IC₅₀ values of 75.58 and 87.28 μg/ml, respectively. More studies are required to isolate and identify the bioactive compounds from these two Angophora species and to determine their mode of action against pancreatic malignancies.     

The contrasting roles of Th17 immunity in human health and disease

The human immune system is a tightly regulated network that protects the host from disease. An important aspect of this is the balance between pro‐inflammatory Th17 cells and anti‐inflammatory T regulatory (Treg) cells in maintaining immune homeostasis. Foxp3+ Treg are critical for sustaining immune tolerance through IL‐10 and transforming growth factor‐β while related orphan receptor‐γt+ Th17 cells promote immunopathology and auto‐inflammatory diseases through the actions of IL‐17A, IL‐21 and IL‐22. Therefore, imbalance between Treg and Th17 cells can result in serious pathology in many organs and tissues. Recently, certain IL‐17‐producing cells have been found to be protective against infectious disease, particularly in relation to extracellular bacteria such Streptococcus pneumoniae; a number of other novel IL‐17‐secreting cell populations have also been reported to protect against a variety of other pathogens. In this mini‐review, the dual roles of Treg and Th17 cells are discussed in the context of autoimmunity and infections, highlighting recent advances in the field. Development of novel strategies specifically designed to target these critical immune response pathways will become increasingly important in maintenance of human health.     

Microbial desulfurization of gasoline by free whole-cells of Rhodococcus erythropolis XP

Rhodococcus erythropolis XP could grow well with condensed thiophenes, mono-thiophenic compounds and mercaptans present in gasoline. Rhodococcus erythropolis XP was also capable of efficiently degrading the condensed thiophenes in resting cell as well as biphasic reactions in which n-octane served as a model oil phase. Free whole cells of R. erythropolis XP were adopted to desulfurize fluid catalytic cracking (FCC) and straight-run (SR) gasoline oils. About 30% of the sulfur content of FCC gasoline and 85% of sulfur in SR gasoline were reduced, respectively. Gas chromatography analysis with atomic emission detection also showed depletion of sulfur compounds in SR gasoline. Rhodococcus erythropolis XP could partly resist the toxicity of gasoline and had an application potential to biodesulfurization of gasoline.     

从鼠黑色素瘤细胞系中分离和鉴定癌干细胞样细胞

目的：从鼠黑色素瘤BL6F10细胞系中分离与鉴定癌干细胞（CSC）样细胞,为今后对CSC的鉴定及靶向治疗奠定基础。方法：用不同免疫磁珠标记的单克隆抗体,从BL6F10细胞系中分离有特征性CD表型的瘤细胞,体外观察不同CD表型瘤细胞在软琼脂培养基上形成克隆的能力;将这些瘤细胞皮下注射到C57BL/6小鼠,比较其致瘤性。结果：从BL6F10细胞系中分离出不同CD表型的特征性瘤细胞;在软琼脂培养基上,CD133^＋、CD44^＋和CD44^＋CD133^＋细胞克隆形成率分别高于CD133^-、CD44^-和CD44^＋CD133^-细胞;CD133^＋、CD44^＋、CD44^＋CD133^＋和CD44^＋CD133^＋CD24＋细胞在小鼠体内的致瘤性分别强于CD133^-、CD44^-、CD44^＋CD133^-和CD44^＋CD133^＋CD24^-细胞。结论：CD44^＋CD133^＋CD24＋表型的BL6F10细胞的某些生物学特性与CSC样细胞相似,具有CSC特征,这些实验结果为进一步鉴定BL6F10细胞系中的CSC提供了重要的实验资料。     

基于分段伪氨基酸组成成分特征提取方法预测蛋白质亚细胞定位

蛋白质的亚细胞定位与蛋白质的功能密切相关,其定位预测有助于人们了解蛋白质功能.文章提出一种分段伪氨基酸组成成分特征提取方法,采用支持向量机算法对Chou构建的两个蛋白质亚细胞定位数据集(C2129,CS2423)进行了分类研究,并采用总分类精度Q3、内容平衡精度指数Q9等参数评估预测分类系统性能.预测结果表明,基于分段伪氨基酸组成成分特征提取方法的预测性能,优于基于完整蛋白质序列的伪氨基酸组成成分特征提取方法.例如,基于分段矩描述子伪氨基酸组成成分特征提取方法,数据集C2129的Q3和Q9分别为84.7%和60.8%,比基于完整蛋白质序列的矩描述子伪氨基酸组成成分特征提取方法分别提高1.8和2.2个百分点,且Q3比现有Xiao等人的方法提高了9.1个百分点.基于分段伪氨基酸组成成分特征提取方法构成的特征向量不仅包含残基之间的位置信息,而且还包含蛋白质子序列之问的耦合信息,另外蛋白质分段子序列可能和蛋白质的功能域有一定的联系,从而使这一方法能够有效地预测蛋白质亚细胞定位.     

Social organization of black-and-white snub-nosed monkeys (Rhinopithecus bieti) at Deqin, China

Data on social organization of two bands of black-and-white snub-nosed monkeys (Rhinopithecus bieti) were collected when the monkeys were crossing an open spot at Nanren and Bamei (northwest of Yunnan, China) using a sampling rule where individuals within one social unit are spatially closer to each other than individuals between social units. The typical pattern of social organization in this sample was multiple adult females (AFs) and their offspring with one adult male (AM) in a one-male unit (OMU), similar to that of many other colobines. In such units, on average one male is associated with 4.0 AFs and 2.5 of their offspring. Moreover, there are multimale/multifemale units and monogamous units besides OMUs. All bisexual units traveled together with at least one all-male unit as a cohesive band. In two bands of monkeys, 87% of AMs in bisexual units were within OMUs, 7.8% within monogamous units and 5.2% within multimale, multifemale units. In the Bamei band, 6.7% of AMs were in the all-male unit. The size of OMUs in the Nanren band was larger than that of the Bamei band, with more AFs and juveniles, which may be related to better conservation in the Nanren band's habitat. For the Nanren band, the average number of AFs in OMUs varied across time, increasing from 4.3 in 1994 to 5.1 in 2001, and then decreasing to 3.8 in 2005. This article suggests three possible explanations for this variation, but more data are needed for these hypotheses to be tested.     

Ser84是spindlin1定位与功能发挥的关键位点

spindlin1为作者所在研究组克隆并命名的肿瘤相关新基因,之前研究表明spindlin1蛋白定位于细胞核,并有可能通过对TCF-4通路的调节参与对肿瘤细胞生长和周期的调控．为进一步探索spindlin1的作用机制,明确spindlin1结构与功能的关系,在生物信息学分析及晶体结构解析的基础上,构建系列突变表达载体,首先以spindlin1蛋白亚细胞定位为指标,观察野生型及系列突变体spindlin1蛋白的亚细胞定位,并进一步检测野生型及突变体spindlin1对TCF-4荧光素酶报告基因转录活性的调控作用,以明确spindlin1定位与功能的关键位点．结果表明：Ser14＋Ser84、Ser84＋Ser99、Ser14＋Ser84＋Ser99位点Ser到Ala的联合突变能使野生型融合蛋白在细胞核内集中分布的特性消失,成为全细胞弥散分布,而Ser14、Ser84、Ser99各位点的单独突变或Ser14＋Ser99联合突变对spindlin1蛋白的细胞核内分布没有影响．与此同时,对TCF-4荧光素酶报告基因活性的分析表明,Ser14＋Ser84、Ser84＋Ser99、Ser14＋Ser84＋Ser99的联合突变使spindlin1对其活性的激活作用消失或降低．上述结果表明,Ser84是spindlin1细胞定位与功能发挥的关键位点,其作用发挥需要Ser14与Ser99的协助．     

Comparative genomics of emerging human ehrlichiosis agents

Anaplasma (formerly Ehrlichia) phagocytophilum, Ehrlichia chaffeensis, and Neorickettsia (formerly Ehrlichia) sennetsu are intracellular vector-borne pathogens that cause human ehrlichiosis, an emerging infectious disease. We present the complete genome sequences of these organisms along with comparisons to other organisms in the Rickettsiales order. Ehrlichia spp. and Anaplasma spp. display a unique large expansion of immunodominant outer membrane proteins facilitating antigenic variation. All Rickettsiales have a diminished ability to synthesize amino acids compared to their closest free-living relatives. Unlike members of the Rickettsiaceae family, these pathogenic Anaplasmataceae are capable of making all major vitamins, cofactors, and nucleotides, which could confer a beneficial role in the invertebrate vector or the vertebrate host. Further analysis identified proteins potentially involved in vacuole confinement of the Anaplasmataceae, a life cycle involving a hematophagous vector, vertebrate pathogenesis, human pathogenesis, and lack of transovarial transmission. These discoveries provide significant insights into the biology of these obligate intracellular pathogens.