PBAN gene architecture and expression in the fire ant, solenopsis invicta

The PBAN/pyrokinin peptides are a major neuropeptide family characterized by a common FXPRLamide at the C-termini. These peptides are distributed ubiquitously in the Insecta and are involved in many essential endocrine functions, e.g. pheromone production. We report the gene architecture of the fire ant Solenopsis invicta PBAN (Soi-PBAN) gene, including the exon and intron boundaries. Furthermore, we quantified expression of the Soi-PBAN mRNA in the head, thorax and abdomen of the fire ant. The Soi-PBAN gene is comprised three exons and two introns, all composed of 13,358 nucleotides, which is 2-4 times larger than lepidopteran PBAN genes. The overall pattern of the PBAN immunoreactive neuron number and localization was similar for female and male alates, inseminated female delates, workers and queens. The Soi-PBAN mRNA expression level was highest in the head, followed by the thorax, and abdomen of adult ants. Expression in the abdominal tissues was expected to be similar to the head, or at least higher than thorax because strong PBAN immunoreactive neurons were detected previously in brain-subesophageal and abdominal ganglia. This result suggests that another FXPRL gene could be dominant in the abdomen rather than Soi-PBAN gene.     

Model of magnetic field-induced mitotic apparatus reorientation in frog eggs

Recent experiments have shown that intense static magnetic fields can alter the geometry of the early cell cleavages of Xenopus laevis eggs. The changes depend on field orientation, strength, and timing. We present a model that qualitatively accounts for these effects and which presumes that the structures involved in cell division are cylindrically symmetric and diamagnetically anisotropic and that the geometry of the centrosome replication and spreading processes dictates the nominal cleavage geometry. Within this model, the altered cleavage geometry results from the magnetic field-induced realignment of mitotic structures, which causes a realignment of the centrosome replication and spreading processes.     

Functional correlation between habitat use and leg morphology in birds (Aves)

Many of the morphological features of animals are considered to be adaptations to the habitat that the animals utilize. The habitats utilized by birds vary, perhaps more than for any other group of vertebrates. Here, we study possible adaptations in the morphology of the skeletal elements of the hind limbs to the habitat of birds. Measurements of the lengths of the femur, tibiotarsus and tarsometatarsus of 323 bird species from 74 families are used together with body mass data, taken from the literature. The species are separated into six habitat groups on the basis of literature data on leg use. A discriminant analysis of the groups based on leg morphology shows that swimming birds, wading birds and ground living species are more easily identified than other birds. Furthermore, functional predictions are made for each group based on ecological and mechanical considerations. The groups were tested for deviation from the norm for all birds for three indices of size- and leg-length-independent measures of the bones and for a size-independent-index of leg length. Several of the groups deviate significantly from the norm for one or more of the indices used, suggesting habitat-related adaptations in the leg morphology of birds. The results indicate that stability is an important factor affecting the leg morphology of primarily long-legged birds. The femur seems to be more important than previously thought because several of the groups have high femur indices, suggesting a positive selection pressure on this bone. On a general basis, the results suggest that the effect of leg length should be taken into consideration when discussing adaptations of mass-independent lengths of the long bones of the legs of birds.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 79, 461–484.     

Screening and typing of Patagonian wine yeasts for glycosidase activities

AIMS: The purpose of this study was to select autochthonous glycosidase producer yeasts with potential use in industrial production of Patagonian red wines. METHODS AND RESULTS: The study was carried out in oenological autochthonous yeasts from Comahue region (Argentinean North Patagonia). A set of screenable yeast phenotypic characteristics indicative of their potential usefulness in more aromatic red wine production was defined and tested in both, Saccharomyces and non-Saccharomyces populations. Twelve isolates showing six different glycosidase phenotypes were selected and they were characterized at species and strain levels using molecular methods. A close correlation between molecular and phenotypic characteristics was observed. Five strains belonging to Candida guilliermondii, C. pulcherrima and Kloeckera apiculata with highest constitutive beta-glucosidase activity levels without anthocyanase activity were discriminated. Some of them also showed constitutive beta-xylosidase and inductive alpha-rhamnosidase activities. CONCLUSIONS: The extension of the selection of oenological yeast to non-Saccharomyces species provided strains possessing novel and interesting oenological characteristics which could have significant implications in the production of more aromatic young red wine. SIGNIFICANCE AND IMPACT OF THE STUDY: As these non-Saccharomyces are indigenous to wine, they can be used in mixed starters at the beginning or as pure cultures at the end fermentation to contribute in enhancing the wine nuance that is typical of this specific area.     

Pseudacteon decapitating flies (Diptera: Phoridae): Are they potential vectors of the fire ant pathogens Kneallhazia (=Thelohania) solenopsae (Microsporidia: Thelohaniidae) and Vairimorpha invictae (Microsporidia: Burenellidae)?

Fire ant decapitating flies in the genus Pseudacteon were tested for their potential as hosts or vectors of two microsporidian pathogens of the red imported fire ant, Solenopsis invicta. Decapitating flies that attacked or were reared from S. invicta workers infected by Kneallhazia (=Thelohania) solenopsae or Vairimorpha invictae were tested for either pathogen by polymerase chain reaction (PCR) tests or visual examination for spores using phase microscopy. Three species of fire ant decapitating flies acquired the pathogen, Kneallhazia solenopsae. K. solenopsae was detected in 58% of pooled samples of Pseudacteon obtusus flies and 44% of pooled samples of Pseudacteon cultellatus that developed in K. solenopsae-infected fire ant workers. K. solenopsae was also found in 17% of pooled samples of field-collected Pseudacteon curvatus. In contrast, the microsporidium V. invictae was not detected in P. obtusus reared from V. invictae-infected S. invicta workers. Neither K. solenopsae nor V. invictae were detected in any of the hovering or ovipositing flies in the laboratory exposures, indicating no mechanical acquisition of the microsporidia occurred during oviposition activity. Greater than 92% of the P. obtusus that developed in K. solenopsae-infected ants survived and emerged as adults, thus indicating no detrimental effects of the microsporidium on pupal development and emergence. These results indicate that Pseudacteon decapitating flies may be able to vector K. solenopsae but not V. invictae among fire ants. Further tests are planned to determine if flies containing K. solenopsae are capable of transferring this pathogen either during oviposition or by being consumed by fire ant larvae.     

Identification of novel deregulated RNA metabolism-related genes in non-small cell lung cancer

Lung cancer is a leading cause of cancer death worldwide. Several alterations in RNA metabolism have been found in lung cancer cells; this suggests that RNA metabolism-related molecules are involved in the development of this pathology. In this study, we searched for RNA metabolism-related genes that exhibit different expression levels between normal and tumor lung tissues. We identified eight genes differentially expressed in lung adenocarcinoma microarray datasets. Of these, seven were up-regulated whereas one was down-regulated. Interestingly, most of these genes had not previously been associated with lung cancer. These genes play diverse roles in mRNA metabolism: three are associated with the spliceosome (ASCL3L1, SNRPB and SNRPE), whereas others participate in RNA-related processes such as translation (MARS and MRPL3), mRNA stability (PCBPC1), mRNA transport (RAE), or mRNA editing (ADAR2, also known as ADARB1). Moreover, we found a high incidence of loss of heterozygosity at chromosome 21q22.3, where the ADAR2 locus is located, in NSCLC cell lines and primary tissues, suggesting that the downregulation of ADAR2 in lung cancer is associated with specific genetic losses. Finally, in a series of adenocarcinoma patients, the expression of five of the deregulated genes (ADAR2, MARS, RAE, SNRPB and SNRPE) correlated with prognosis. Taken together, these results support the hypothesis that changes in RNA metabolism are involved in the pathogenesis of lung cancer, and identify new potential targets for the treatment of this disease.     

Lionel Penrose and the concept of normal variation in human intelligence

Lionel Penrose (1898-1972) was an important leader during the mid-20th century decline of eugenics and the development of modern medical genetics. However, historians have paid little attention to his radical theoretical challenges to mainline eugenic concepts of mental disease. Working from a classification system developed with his colleague, E. O. Lewis, Penrose developed a statistically sophisticated and clinically grounded refutation of the popular position that low intelligence is inherently a disease state. In the early 1930s, Penrose advocated dividing "mental defect" (low intelligence) into two categories: "pathological mental defect," which is a disease state that can be traced to a distinct genetic or environmental cause, and "subcultural mental defect," which is not an inherent disease state, but rather a statistically necessary manifestation of human variation in intelligence. I explore the historical context and theoretical import of this contribution, discussing its rejection of typological thinking and noting that it preceded Theodosius Dobzhansky's better-known defense of human diversity. I illustrate the importance of Penrose's contribution with a discussion of an analogous situation in contemporary medicine, the controversial practice of using human growth hormone injections to treat "idiopathic short stature" (mere diminutive height, with no distinct cause). I show how Penrose's contributions to understanding human variation make such treatments appear quite misguided.     

披针叶黄华的界定

通过对标本的比较研究及广泛的野外考察,界定了披针叶黄华,承认了一个种级名称Thermopsis lupinoides（L．）Link．并组合了9个新异名。     

三种啮齿类动物非酒精性脂肪肝形成及机制探讨

目的 分析物种差异对NAFLD模型复制的影响,探讨不同鼠种NAFLD形成及其机制.方法 长爪沙鼠、SD大鼠、ICR小鼠各20只,按种属随机分为对照组及模型组,对照组给予普通饲料,模型组给予高脂饲料.16周后,观察肝脏HE及Mallory三色染色病理变化,计算肝指数,检测血清血脂(CHO、TG、LDL-c、HDL-c)、肝功能(GOP、GPT)及肝组织中抗氧化酶(SOD、GSH-PX、CAT)活性及羟脯氨酸(Hyp)、丙二醛(MDA)、游离脂肪酸(FFA)水平.结果 与对照组比较,各模型组:沙鼠Hyp、CHO、TG、LDL-c、HDL-c、肝指数、GOP、GPT、MDA、FFA均升高,SOD、GSH-PX、CAT活性降低(P＜0.05,P＜0.01),肝脏出现纤维化;大鼠CHO、肝指数、GOP、GPT、FFA、SOD活性升高,MDA含量、GSH-PX、CAT活性降低(P ＜0.05,P＜0.01),有局灶性脂肪肝炎;小鼠CHO、LDL-c、HDL-c、肝指数、CAT活性升高,MDA含量降低(P ＜0.05,P＜0.01),肝脏病理正常.结论 三种动物在脂质代谢、肝功能、氧化应激等方面有显著的差异,并形成了不同的NAFLD模型:沙鼠形成伴高TG、CHO血症的肝纤维化模型、大鼠形成伴高CHO血症的局灶性脂肪肝炎模型、小鼠形成高胆固醇血症模型但肝脏未发生明显的病理改变.     

内蒙古大兴安岭森林可燃物燃烧释放PM2.5中水溶性离子排放特性

研究森林可燃物燃烧释放的细颗粒物(PM2.5)的排放因子对于揭示森林火灾对大气和生态系统的影响至关重要,而水溶性离子是细颗粒物的重要化学成分,对颗粒物的形成具有重要意义.利用自主设计的生物质燃烧系统,模拟内蒙古大兴安岭5种典型乔木(蒙古栎、白桦、兴安落叶松、黑桦、山杨)的3种组成部分(树干、树枝、树皮)及其地表死可燃物...