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Manoeli Lupatini Afnan Khalil Ahmad Suleiman Rodrigo Josemar Seminoti Jacques Zaida Inês Antoniolli Eiko Eurya Kuramae Flávio Anastácio de Oliveira Camargo Luiz Fernando Würdig Roesch 《PloS one》2013,8(10)
The Pampa biome is considered one of the main hotspots of the world’s biodiversity and it is estimated that half of its original vegetation was removed and converted to agricultural land and tree plantations. Although an increasing amount of knowledge is being assembled regarding the response of soil bacterial communities to land use change, to the associated plant community and to soil properties, our understanding about how these interactions affect the microbial community from the Brazilian Pampa is still poor and incomplete. In this study, we hypothesized that the same soil type from the same geographic region but under distinct land use present dissimilar soil bacterial communities. To test this hypothesis, we assessed the soil bacterial communities from four land-uses within the same soil type by 454-pyrosequencing of 16S rRNA gene and by soil microbial activity analyzes. We found that the same soil type under different land uses harbor similar (but not equal) bacterial communities and the differences were controlled by many microbial taxa. No differences regarding diversity and richness between natural areas and areas under anthropogenic disturbance were detected. However, the measures of microbial activity did not converge with the 16S rRNA data supporting the idea that the coupling between functioning and composition of bacterial communities is not necessarily correlated. 相似文献
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为了研究高原鼢鼠扰动后退化高寒草甸恢复演替的动态过程,利用常规实验室分析方法和Biolog-ECO生态板法对青藏高原东缘高寒草甸土壤养分和微生物功能多样性进行分析.结果表明: 高原鼢鼠扰动显著降低了土壤有机质、全氮、速效氮和速效磷含量,对土壤全磷和全钾含量无显著影响;在一定植被恢复年限内,土壤微生物的碳源利用率、Shannon、Pielou和McIntosh指数随着植被恢复年限的增加而升高;主成分分析表明,碳水化合物和氨基酸是土壤微生物利用的主要碳源类型;冗余分析表明,土壤pH、有机质、全氮、速效氮和全钾是影响土壤微生物代谢活性和功能多样性的主要因子.不同植被恢复年限土壤微生物功能多样性的变化可能是对地上植被、土壤微生物群落组成和土壤养分变化的响应. 相似文献
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Chronotype has long been associated with mental disorders and temperamental features. This study aims to investigate the association of circadian preference with a new model for emotional and affective temperament. In this Web survey, 6436 subjects (27.2% males) answered the Affective and Emotional Composite Temperament Scale (AFECTS), the Circadian Energy Scale (CIRENS), and questions on subjective sleep parameters for a sleep-based chronotype measure. Temperament was more strongly correlated with daily energy score than with chronotype. For emotional dimensions, Volition, Coping, and Control positively correlated with high and stable daily energy, contrary to Sensitivity. Evening types showed a less adaptive emotional profile than morning and intermediate types, who showed a relatively similar emotional pattern. Focus and order (facets of Control), energy (facet of Volition), caution (facet of Inhibition), and problem facing (facet of Coping) were distinctive for the three circadian types, being particularly low in evening types and high in morning types. Differences between affective temperaments were more pronounced for morning and afternoon than for evening scores. Cyclothymic and euphoric temperaments, which relate to bipolar disorders, and apathetic, volatile, and disinhibited temperaments, which relate to attention-deficit/hyperactivity disorder (ADHD), showed the latest chronotype (i.e., evening preference). In conclusion, temperament was more associated with absolute energy levels than with chronotype. Evening types had less emotional control, coping, volition, and caution, and more affective instability and externalization. The circadian daily energy profile can be very informative about human temperament and vice versa, and their combined assessment may be useful in the evaluation of psychiatric patients. 相似文献
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Bonjardim LR Cunha ES Guimarães AG Santana MF Oliveira MG Serafini MR Araújo AA Antoniolli AR Cavalcanti SC Santos MR Quintans-Júnior LJ 《Zeitschrift für Naturforschung. C, Journal of biosciences》2012,67(1-2):15-21
We attempted to identify the antinociceptive and anti-inflammatory actions of the monoterpene p-cymene. Firstly, behavioural screening was carried out to verify the influence of p-cymene [25, 50, and 100 mg/kg intraperitoneal (i.p.)] on the central nervous system (CNS) activity. The antinociceptive activity of p-cymene was evaluated by the acetic acid-induced writhing response, formalin, and hot-plate test, respectively. The leukocyte migration induced by injection of carrageenan was used to assess the anti-inflammatory activity. p-Cymene showed depressant activity on CNS after 4 h of treatment and also a possible action on the autonomous nervous system (ANS), mainly at the dose of 100 mg/kg (i.p.). It was found that p-cymene (50 and 100 mg/kg, i.p.) significantly (p < 0.05) reduced the writhing responses induced by acetic acid. p-Cymene also decreased the licking time in the first and second phase, respectively, of the formalin test. The results of the hot-plate test showed that all doses of p-cymene increased significantly the latency time of the response to the thermal stimulus in both licking and jumping parameters. In addition, there was a significantly (p < 0.05) decreased leukocyte migration at all doses of p-cymene. The experimental data demonstrate that p-cymene possesses antinociceptive and anti-inflammatory activities. 相似文献
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M.F. Arrigoni-Blank A.R. Antoniolli L.C. Caetano D.A. Campos A.F. Blank P.B. Alves 《Phytomedicine》2008,15(5):334-339
Hyptis pectinata L. Poit (Lamiaceae) is known popularly in Brazil as “sambacaita” or “canudinho” and is used in the treatment of inflammations, bacterial infections and ache. The antinociceptive activity of the volatile oils of six genotypes, at doses of 100, 200 and 400 mg/kg body wt., were investigated using abdominal writhe models induced by acetic acid and hot plate tests. The volatile oils of all the genotypes are composed mainly of sesquiterpenoids. All the genotypes showed antinociceptive effects in both models used; the SAM002 genotype showed the major inhibitory effect at dose of 100 mg/kg body wt. These results suggest that the volatile oil of H. pectinata has peripheral (writhe reduction) and central (time delay of thermal reaction) effects. These observations indicate that H. pectinata may be useful as an analgesic drug. 相似文献
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L.J. Quintans-Júnior T.T. Souza B.S. Leite N.M.N. Lessa L.R. Bonjardim M.R.V. Santos P.B. Alves A.F. Blank A.R. Antoniolli 《Phytomedicine》2008,15(8):619-624
Cymbopogon winterianus (Poaceae) is used for its analgesic, anxiolytic and anticonvulsant properties in Brazilian folk medicine. This report aimed to perform phythochemical screening and to investigate the possible anticonvulsant effects of the essential oil (EO) from fresh leaves of C. winterianus in different models of epilepsy. The phytochemical analysis of EO showed presence of geraniol (40.06%), citronellal (27.44%) and citronellol (10.45%) as the main compounds. A behavioral screening demonstrated that EO (100, 200 and 400 mg/kg; ip) caused depressant activity on CNS. When administered concurrently, EO (200 and 400 mg/kg, ip) significantly reduced the number of animals that exhibited PTZ- and PIC-induced seizures in 50% of the experimental animals (p<0.05). Additionally, EO (100, 200 and 400 mg/kg, ip) significantly increased (p<0.05) the latencies of clonic seizures induced by STR. Our results demonstrated a possible activity anticonvulsant of the EO. 相似文献
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KAI ZHAO ZI YUAN DUAN†‡ ZUO GANG PENG†§ SONG CHANG GUO JUN BING LI† SHUN PING HE† XIN QUAN ZHAO 《Molecular ecology》2009,18(17):3616-3628
Although new empirical evidence shows that sympatric speciation has occurred in some species, there are few indisputable model organisms for this process of speciation. The two subspecies ( Gymnocypris eckloni eckloni and G . e . scoliostomus ) of the schizothoracine Gymnocypris fish species complex from a small glacier lake in the Tibetan Plateau, Lake Sunmcuo, fit several of the key characteristics of the sympatric speciation model. We used combined mitochondrial control region sequences and the cytochrome b gene (1894 bp) to address the phylogenetics and population genetics of 232 specimens of G . e . eckloni and G . e . scoliostomus , as well as all of its closely related sister species. We found that: (i) a total of four old lineages were uncovered in the widespread G . e . eckloni , of which only one was shown to be shared with all G . e . scoliostomus individuals and (ii) the new subspecies ( G . e . scoliostomus ) evolved in Lake Sunmcuo from the ancestral G . e . eckloni population within approximately 0.057 Ma. These two taxa of the species complex are morphologically distinct, and reproductive isolation is further suggested. Ecological disruptive selection based on morphological traits (e.g. mouth cleft characters) and food utilization may be a mechanism of incipient speciation of two sympatric populations within Lake Sunmcuo. This study provides the first genetic evidence for sympatric speciation in the schizothoracine fish. 相似文献
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采用高盐的牛肉膏蛋白胨培养基(盐浓度为8%NaCl),研究江苏省盐城市盐场土壤里中度嗜盐菌的分布情况及种群特征。从盐城市的射阳、新滩、灌东三处盐场土壤中共采集和分离得到13株中度嗜盐菌。通过形态观察、生理生化分析、16S rRNA序列分析和系统进化分析等方法进行初步鉴定,结果表明:分离到的中度嗜盐菌分属3个属,Virgibacillus属4株、Halomonas属7株和Marinobacter属2株。研究结果揭示盐城市的盐场存在较为丰富的中度嗜盐菌,具有较高的研究和利用价值。 相似文献