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31.
Phenological studies are especially important in order to understand the ecological process operating at temporal level. The western slopes of the northern Chilean Andes at about 3,500 m asl are a mosaic of arid environments in which precipitations are highly seasonal, mostly concentrated in summer. Teriocolias zelia andina Forbes (Lepidoptera: Pieridae) is one of the most conspicuous and regularly observed butterflies flying in this region; it is a host specialist associated with the native shrub Senna birostris var. arequipensis (Fabaceae). The objectives of this study were (1) to characterize the temporal variations in the relative abundance of eggs of this host-specialist butterfly and (2) to examine the relationship of these variations with leaf phenology. Monthly samplings of eggs were carried out from February 2011 to January 2012. Circular statistical analyses of the relative abundance of eggs indicated clustered distribution along the year with the mean vector in June. Temporal variation in the relative abundance of eggs was correlated (Spearman rank correlation test) with the availability of plant substrate for egg laying and larval feeding. 相似文献
32.
Male, female, pupa, larva and egg of a new genus and species of Gracillariidae (Gracillariinae), Spinivalva gaucha Moreira and Vargas from southern Brazil are described and illustrated with the aid of optical and scanning electron microscopy. A preliminary analysis of mitochondrial DNA sequences including members of related lineages is also provided. The immature stages are associated with Passiflora actinia, Passiflora misera and Passiflora suberosa (Passifloraceae), and build mines on the adaxial leaf surface. Initially the mines are serpentine in shape, but later in larval ontogeny become a blotch type. Although the larvae are hypermetamorphic as in other Gracillariidae, there is no sap-feeding instar in Spinivalva gaucha; the larva feeds on the palisade parenchyma, thus producing granular frass during all instars. Pupation occurs outside the mine; prior to pupating, the larva excretes numerous bubbles that are placed in rows on the lateral margins of the cocoon external surface. This is the second genus of gracillariid moth described for the Atlantic Rain Forest, and the second gracillariid species known to be associated with Passifloraceae. 相似文献
33.
Fabrizio Chiodo Marco Marradi Boris Tefsen Harm Snippe Irma van Die Soledad Penadés 《PloS one》2013,8(8)
Improved detection of anti-carbohydrate antibodies is a need in clinical identification of biomarkers for cancer cells or pathogens. Here, we report a new ELISA approach for the detection of specific immunoglobulins (IgGs) against carbohydrates. Two nanometer gold glyconanoparticles bearing oligosaccharide epitopes of HIV or Streptococcus pneumoniae were used as antigens to coat ELISA-plates. A ~3,000-fold improved detection of specific IgGs in mice immunized against S. pneumoniae respect to the well known BSA-glycoconjugate ELISA was achieved. Moreover, these multivalent glyconanoparticles have been employed in solid phase assays to detect the carbohydrate-dependent binding of human dendritic cells and the lectin DC-SIGN. Multivalent glyconanoparticles in ELISA provide a versatile, easy and highly sensitive method to detect and quantify the binding of glycan to proteins and to facilitate the identification of biomarkers. 相似文献
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35.
Eldamária de Vargas Wolfgramm Lyvia Neves Rebello Alves Elaine Stur Thaís Tristão Tovar Mariana Penha De Nadai Sartori Allan Kardec de Castro Neto Iúri Drumond Louro 《Molecular biology reports》2013,40(3):2139-2144
Breast cancer is a heterogeneous disease, previously associated with genomic instability. Our aim was to analyze microsatellite markers in order to determine patterns and levels of instability, as well as possible correlations with histopathological parameters. Polymerase chain reaction was used to characterize microsatellite instability (MSI) and loss of heterozygosity (LOH) in 107 breast carcinomas at twelve microsatellite loci. Some of the markers were selected because of their relation to steroid hormone metabolism, which seems to be related to sporadic breast cancer risk. D5S346 and D17S250 markers showed a statistically significant frequency of MSI. LOH in D3S1611, D17S250, AR and ER-β were associated with some parameters of worse prognosis. Marker group analysis showed that CYP19, AR and ER-β were related to histological grade III, ER-negative and PR-negative cases. Our results suggest that marker group analysis may be preferred to the single marker strategy, being predictive of worst prognosis when single markers are unable to provide such information. A further evaluation of steroid metabolism genes and their association with low penetrance genes in breast cancer may be useful. 相似文献
36.
Rizky Abdulah Herlambang Noerjasin Leri Septiani Mutakin Irma R. Defi Eka W. Suradji Irma M. Puspitasari Melisa I. Barliana Chiho Yamazaki Minato Nakazawa Hiroshi Koyama 《Biological trace element research》2013,154(1):1-6
Selenium is an essential nutrient for human health, and maternal selenium concentration has been reported to be associated with pregnancy outcome. To further investigate the possible role of selenium (Se) in miscarriage, we conducted a case–control study to evaluate the correlations among selenium status, glutathione peroxidase activity, and spontaneous abortion. A total of 46 subjects with normal pregnancies and 25 subjects with spontaneous abortion were recruited, and their serum selenium concentrations and serum glutathione peroxidase activities were analyzed. The total serum selenium concentrations in subjects with normal pregnancies were significantly higher than those of subjects with spontaneous abortion; however, the glutathione peroxidase activities were similar in both groups. We further separated the subjects into smoking and nonsmoking groups, and the logistic regression analysis suggested that total serum selenium concentration, but not serum glutathione peroxidase activity or smoking, was significantly correlated with the incidence of miscarriage. The present study thus reaffirms that low serum selenium levels are associated with miscarriage and that selenium plays an important role in pregnancy maintenance. 相似文献
37.
Status epilepticus (SE) is a life threatening condition that often precedes the development of epilepsy. Traditional treatments for epilepsy have been focused on targeting neuronal mechanisms contributing to hyperexcitability, however, approximately 30% of patients with epilepsy do not respond to existing neurocentric pharmacotherapies. A growing body of evidence has demonstrated that profound changes in the morphology and function of astrocytes accompany SE and persist in epilepsy. Astrocytes are increasingly recognized for their diverse roles in modulating neuronal activity, and understanding the changes in astrocytes following SE could provide important clues about the mechanisms underlying seizure generation and termination. By understanding the contributions of astrocytes to the network changes underlying epileptogenesis and the development of epilepsy, we will gain a greater appreciation of the contributions of astrocytes to dynamic circuit changes, which will enable us to develop more successful therapies to prevent and treat epilepsy. This review summarizes changes in astrocytes following SE in animal models and human temporal lobe epilepsy and addresses the functional consequences of those changes that may provide clues to the process of epileptogenesis. 相似文献
38.
James F. Harwood Roger I. Vargas James R. Carey 《Entomologia Experimentalis et Applicata》2013,147(1):73-81
Injuries frequently accumulate with age in nature. Despite the commonality of injury and the resulting impairment, there are limited experimental data for the effects of impairment on life history trade‐offs between reproduction and survival in insects. We tested the effects of artificial injury and the resulting impairment on the reproductive costs and behavior of male medflies, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). Treatment flies were impaired by amputating tarsomere segments 2–5 from the right foreleg at either eclosion or age 22 days. The effect of impairment and age on the cost of reproduction was tested by varying the timing of female availability among the treatments. Courtship behavior and copulation rates were observed hourly from age 2–5 days to determine the effects of impairment on reproductive behavior. Female access combined with the impairment reduced the life expectancy of males more than the impairment alone, whereas the health effect of amputation was influenced by age. Conversely, the risk of death due to impairment was not influenced by the males' mating status prior to amputation. The males' copulation success was reduced due to impairment, whereas courtship behavior was not affected. Impairment does not reduce the males' impulse to mate, but decreases the females' receptivity to copulation, while also increasing the cost of each successful mating. Overall, minor impairment lowers the reproductive success of males and reduces longevity. 相似文献
39.
Anthropogenic global climate change is expected to cause severe range contractions among alpine plants. Alpine areas in the Mediterranean region are of special concern because of the high abundance of endemic species with narrow ranges. This study combined species distribution models, population structure analyses and Bayesian skyline plots to trace the past and future distribution and diversity of Linaria glacialis, an endangered narrow endemic species that inhabits summits of Sierra Nevada (Spain). The results showed that: (i) the habitat of this alpine‐Mediterranean species in Sierra Nevada suffered little changes during glacial and interglacial stages of late Quaternary; (ii) climatic oscillations in the last millennium (Medieval Warm Period and Little Ice Age) moderately affected the demographic trends of L. glacialis; (iii) future warming conditions will cause severe range contractions; and (iv) genetic diversity will not diminish at the same pace as the distribution range. As a consequence of the low population structure of this species, genetic impoverishment in the alpine zones of Sierra Nevada should be limited during range contraction. We conclude that maintenance of large effective population sizes via high mutation rates and high levels of gene flow may promote the resilience of alpine plant species when confronted with global warming. 相似文献