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1.
The ethyl acetate (EtOAc) soluble fraction of the 85% ethanol (EtOH) extract of the dried bark of Limonia acidissima potently inhibited nitric oxide (NO) production in lipopolysaccharide (LPS) activated BV-2 cells, a microglial cell line. Bioassay-guided column chromatography separation afforded a new stereoisomer of neolignan, (7’E)-(7R,8S)-4-hydroxy-3,5’-dimethoxy-4’,7-epoxy-8,3’-neolig-7’-en-9,9’-diyil diacetate (1), together with two known lignans, (+)-yangambin (2) and (+)-syringaresinol (3), three known triterpenoids, hederatriol (4), basic acid methyl ester (5), and 3β-hydroxyolean-12-en-11-one (6), and four known fatty acid derivatives, cascarillic acid (7), (+)-α-dimorphecolic acid (8), 8(R)-hydroxylinoleic acid (9), and (6Z,9Z,12Z)-pentadecatrienoic acid (10). The structure of the new compound 1 was elucidated by detailed analysis of spectroscopic data and circular dichroism (CD) spectroscopy. Compounds 1, 3-6, and 8-10 isolated from L. acidissima significantly reduced NO production in LPS-stimulated BV-2 microglia cells.  相似文献   

2.
ABSTRACT

Chemical screening of culture medium from the soil fungus Stachybotrys sp. resulted in the isolation of the three new phenylspirodrimanes MBJ-0030 (1), MBJ-0031 (2) and MBJ-0032 (3). Their structures were determined by detailed analysis of spectroscopic data. The absolute configurations of 13 were determined by modified Mosher’s and Marfey’s methods. In addition, cytotoxic and antimicrobial evaluations of the compounds were conducted.  相似文献   

3.
Capsule: Sympatric Marsh Warblers Acrocephalus palustris and Blyth’s Reed Warblers Acrocephalus dumetorum differ significantly in their life history traits.

Aims: To provide a direct comparison of demographic parameters among two sympatric populations of the closely related Marsh Warbler and Blyth’s Reed Warbler.

Methods: We examined breeding phenology and reproductive traits at a 25?ha study plot. We use program MARK to estimate daily nest survival and adult apparent survival rates.

Results: On average, Marsh Warblers laid the first eggs 3 days later than Blyth’s Reed Warblers. Mean clutch size in the Marsh Warbler was significantly lower than in the Blyth’s Reed Warbler. There are no significant differences between the two species for nest daily survival, duration of incubation and nestling periods. Apparent survival of adults was slightly higher in Marsh Warblers than in Blyth’s Reed Warblers.

Conclusion: Our findings suggest that two ecologically similar sympatric species differ significantly in terms of life history traits. We assume that observed differences could be the result of adaptations to environmental factors in the central parts of the species’ ranges or due to differences in mortality on migratory pathways or wintering grounds.  相似文献   

4.
Background: Water resources are of fundamental importance to society, and are better managed by stakeholders who understand resource issues. Gaining such knowledge is a lifelong process best begun at an early age and best supported by educational approaches integrating across science, technology, engineering and mathematics (STEM). Research scientists can bring resource education to young audiences through children’s books and curricula that emphasise and integrate across STEM principals.

Aims: To encourage empathy for the environment in younger students, researchers at the Niwot Ridge Long Term Ecological Research site have developed a children’s book series and methods for training teachers in water science education.

Methods: Children’s books in the My Water series are paired with curricula, hands-on learning kits, teacher development training and dissemination of materials through school districts to further water science education.

Results: Thousands of children and educators have received training through the My Water book series, and a more broadly focused, federally funded Schoolyard Children’s Book Series has grown out of these efforts towards water resource education.

Conclusions: Children’s books and curricula that integrate STEM principals can play a key role in the development of environmental empathy and lifelong learning to support resource management.  相似文献   

5.
BackgroundHonokiol is a pleiotropic compound which been isolated from Magnolia species such as Magnolia grandiflora and Magnolia dealbata. Magnolia species Magnolia grandiflora is used in traditional medicine for the treatment of various diseases.PurposeThe objective of this review is to summarize the pharmacological potential and therapeutic insights of honokiol.Study designHonokiol has been specified as a novel alternative to treat various disorders such as liver cancer, neuroprotective, anti-spasmodic, antidepressant, anti-tumorigenic, antithrombotic, antimicrobial, analgesic properties and others. Therefore, this study designed to represent the in-depth therapeutic potential of honokiol.MethodsLiterature searches in electronic databases, such as Web of Science, Science Direct, PubMed, Google Scholar, and Scopus, were performed using the keywords ‘Honokiol’, ‘Health Benefits’ and ‘Therapeutic Insights’ as the keywords for primary searches and secondary search terms were used as follows: ‘Anticancer’, ‘Oxidative Stress’, ‘Neuroprotective’, ‘Antimicrobial’, ‘Cardioprotection’, ‘Hepatoprotective’, ‘Anti-inflammatory’, ‘Arthritis’, ‘Reproductive Disorders’.ResultsThis promising bioactive compound presented an wide range of therapeutic and biological activities which include liver cancer, neuroprotective, anti-spasmodic, antidepressant, anti-tumorigenic, antithrombotic, antimicrobial, analgesic properties, and others. Its pharmacokinetics has been established in experimental animals, while in humans, this is still speculative. Some of its mechanism for exhibiting its pharmacological effects includes apoptosis of diseased cells, reduction in the expression of defective proteins like P-glycoproteins, inhibition of oxidative stress, suppression of pro-inflammatory cytokines (TNF-α, IL-10 and IL-6), amelioration of impaired hepatic enzymes and reversal of morphological alterations, among others.ConclusionAll these actions displayed by this novel compound could make it serve as a lead in the formulation of drugs with higher efficacy and negligible side effects utilized in the treatment of several human diseases.  相似文献   

6.
Capsule Wood Warblers did not match their reproduction to the caterpillar peak

Aims To study the timing of Wood Warblers’ breeding and nestling diet in relation to caterpillar abundance under primeval conditions in the Bia?owie?a National Park, Poland.

Methods Observations of food brought by parents. Inter‐year and seasonal changes in availability of folivorous caterpillars were assessed by direct counts and caterpillar frass collection.

Results Maximum food requirements occurred two weeks after the peak of caterpillar abundance. The mismatch had no effect on nestlings’ development. Diet varied little across years and habitats, but varied strongly within a season. Following the decline of ‘green’ caterpillars, their proportion in the Wood Warbler diet strongly declined. Caterpillars were replaced by winged insects. Small nestlings received more spiders than older ones.

Conclusion Timing of Wood Warbler breeding in Bia?owie?a National Park was constrained by the females’ arrival time. Birds did not match their reproduction to the caterpillar peak. ‘Green’ caterpillars were the preferred food for nestlings; birds responded to the caterpillar decrease by feeding smaller proportions of them and switching to alternative prey, namely winged insects.  相似文献   

7.
ABSTRACT

Introduction: Due to the relatively low mutation rate and high frequency of copy number variation, finding actionable genetic drivers of high-grade serous carcinoma (HGSC) is a challenging task. Furthermore, emerging studies show that genetic alterations are frequently poorly represented at the protein level adding a layer of complexity. With improvements in large-scale proteomic technologies, proteomics studies have the potential to provide robust analysis of the pathways driving high HGSC behavior.

Areas covered: This review summarizes recent large-scale proteomics findings across adequately sized ovarian cancer sample sets. Key words combined with ‘ovarian cancer’ including ‘proteomics’, ‘proteogenomic’, ‘reverse-phase protein array’, ‘mass spectrometry’, and ‘adaptive response’, were used to search PubMed.

Expert opinion: Proteomics analysis of HGSC as well as their adaptive responses to therapy can uncover new therapeutic liabilities, which can reduce the emergence of drug resistance and potentially improve patient outcomes. There is a pressing need to better understand how the genomic and epigenomic heterogeneity intrinsic to ovarian cancer is reflected at the protein level and how this information could be used to improve patient outcomes.  相似文献   

8.
ABSTRACT

We herein report the introduction of the IS4O (Improving Students’ Scientific Skills by Using Scaffolding Outlines) teaching approach and its implementation to successfully empower students with initial minor planning competences in mastering complex scientific challenges in the course of Germany’s most-renowned scientific competitions. The IS4O teaching approach itself comprises the unique combination of the differentiating teaching methods Backward Planning and Project Mapping as core teaching elements. The beneficial effect of the IS4O teaching approach on the enhancement of the students planning competences is also discussed. Based on the given results, this teaching approach is mandatory to empower students with initial minor competences in completing a scientific competition successfully with very high assignment of tasks.  相似文献   

9.
ObjectiveNoradrenaline and serotonin reuptake inhibitors have been proven to be effective in some cases of ADHD. In this open trial, Matricaria chamomilla, a serotonin and noradrealine reuptake inhibitor, actually used as an antidepressant, has been checked for this indication.MethodThree 14–16-year-old male psychiatric outpatients, diagnosed with attention-deficit disorder (ADHD) have been rated at baseline and while taking Matricaria chamomilla to determine its efficacy as a treatment for ADHD. Improvement was valuated using comparisons of Conners’ parent ratings.ResultsPatients’ mean scores improved for Conners’ hyperactivity, inattention and immaturity factors.ConclusionsAlthough the sample size is very small and therefore generalization is very difficult, this observation indicates that Matricaria chamomilla might be a slightly effective treatment also for ADHD.  相似文献   

10.
ABSTRACT

Capsule: Differences in parental investment between sexes and stage of the breeding period were found in Bonelli’s Eagles Aquila fasciata.

Aims: To describe the sexual differences in parental behaviour of Bonelli’s Eagles and to assess the sex-specific pattern of variation in parental investment in relation to the breeding period.

Methods: Between 2006 and 2016, we monitored the parental behaviour of 11 pairs of Bonelli’s Eagles during the incubation and chick-rearing periods in southeastern Spain. Observations were made using 20–60× telescopes from points overlooking the territory at a distance of about 500–800?m from the nest.

Results: Our results reveal a marked division in parental duties in Bonelli’s Eagles. Females invested more effort in incubation, nest attendance, chick feeding and nest-building, while males contributed more to food provisioning. Nest attendance and feeding by females decreased with time, and both parents adjusted their provisioning effort in relation to nestling age. Most changeovers took place during the middle of the day, when male provisioning rates and temperatures reach their maximum.

Conclusion: Intersexual differences are discussed in the context of the prey capture difficulty hypothesis, which proposes that intra-pair prey differences, due to large sexual size dimorphism, should be particularly advantageous among raptors that pursue agile prey.  相似文献   

11.
PurposeMultiple receptors are co-expressed in many types of cancers. Octreotate (TATE) and Arg-Gly-Asp (RGD) peptides target somatostatin receptor 2 (sstr2) and integrin αvβ3, respectively. We developed and synthesized a heterodimer NOTA-3PEG4-TATE-RGD (3PTATE-RGD) and aimed to investigate its characteristics for dual-targeting sstr2 and integrin αvβ3.MethodsTATE and RGD peptides and 1,4,7-triazacylononane-N’,N’’,N’’’-triacetic acid (NOTA) were linked through a glutamate and polyethylene glycol (PEG) linker, then 3PTATE-RGD was labeled with 68Ga ion. Receptor-binding characteristics and tumor-targeting efficacy were tested in vitro and in vivo using H69 and A549 lung cancer cell lines and tumor-bearing mice models.Results[68Ga]-3PTATE-RGD had comparable sstr2 and integrin αvβ3-binding affinity with monomeric TATE and RGD in cell uptake and PET imaging study, respectively. In the competition study, H69 and A549 tumor uptake of [68Ga]-3PTATE-RGD was completed inhibited in the presence of an excess amount of unlabeled TATE or RGD, respectively. The blocked level didn’t grow when both of TATE and RGD mixture was co-injected with [68Ga]-3PTATE-RGD. The pharmacokinetics of [68Ga]-3PTATE-RGD is comparable with [68Ga]-TATE and [68Ga]-RGD, resulting in a larger application.Conclusion[68Ga]-3PTATE-RGD showed improved and wider tumor-targeting efficacy compared with monomeric TATE and RGD peptides, which warrants its further investigation in detection both of sstr2 and integrin αvβ3-related carcinomas.  相似文献   

12.
IntroductionProstate cancer growth and progression may be linked to neurogenesis and to medical anti- Parkinson treatment, but results are inconclusive. Therefore, we examined the association between Parkinson’s disease and risk of prostate cancer in a population based case-control study.MethodsWe identified 45,429 patients diagnosed with incident prostate cancer during 1997–2010 from the National Cancer Registry. Five age-matched population controls (n = 227,145) were selected for each case. Odds ratios (ORs) adjusted for age and comorbidity for prostate cancer associated with Parkinson’s disease were computed using conditional logistic regression. Analyses were stratified by duration of Parkinson’s disease and stage of prostate cancer (localized and advanced).ResultsIn total, 245 patients (0,5%) and 1656 controls (0,7%) had Parkinson’s disease. Overall, patients with Parkinson’s disease had a 27% lower risk of prostate cancer compared with patients without Parkinson’s disease (adjusted OR (ORa) 0.73; 95% confidence interval (CI), 0.63–0.83).Risk of prostate cancer decreased with increasing duration of Parkinson’s disease.The odds ratios were slightly lower for advanced prostate cancer (ORa, 0.68; 95% CI, 0.52–0.88) than for localized prostate cancer (ORa 0.76; 95% CI, 0.61–0.93).ConclusionParkinson’s disease was associated with a risk reduction overall (27%), which decreased with increasing duration of Parkinson’s disease.  相似文献   

13.
Background: Previous studies have indicated that several plant species had shown remarkable resistance to Pleistocene climate changes and survived the Last Glacial Maximum in scattered ice-free refugia within the European Alps and peripheral areas nearby. The ‘Expansion–Contraction’ model has been proposed to describe the responses of organisms to Pleistocene climate change. Nevertheless, the timing and extent to which species were affected by Quaternary glaciations remain uncertain.

Aims: To test whether the ‘Expansion–Contraction’ model appropriately describes plant distribution responses to Pleistocene climate change in the Western Alps.

Methods: We employed two Bayesian coalescent-based methods on plastid DNA sequences to infer the demographic histories of Ranunculus kuepferi, R. glacialis, Biscutella laevigata, Saxifraga oppositifolia, Primula allionii, P. marginata, Silene cordifolia and Viola argenteria.

Results: R. kuepferi conformed to the ‘Expansion–Contraction’ model, while other species did not. For example, P. allionii showed an alarming population decline during the Middle-Late Pleistocene.

Conclusions: The application of Bayesian coalescent-based methods to plastid DNA data offers useful insights into plant demography as a function of palaeoclimatic events. Our findings favour an idiosyncratic response of plant species in the Western Alps to Pleistocene climate change.  相似文献   

14.

Michael C. Dawson, BEHIND THE MULE: RACE AND CLASS IN AFRICAN‐AMERICAN POLITICS, Princeton, NJ: Princeton University Press, 1994, xii + 234pp., (paper) npl.

Paula D. McClain and Joseph Stewart Jr., ’CAN WE ALL GET ALONG?’: RACIAL AND ETHNIC MINORITIES IN AMERICAN POLITICS, Boulder, CO: Westview, 1995, xv + 208pp., £33.50 and £9.50 (paper).

Joe E. Feagin and Hernán Vera, WHITE RACISM: THE BASICS, New York: Routledge, 1995, xiv + 230pp., £12.99 (paper).  相似文献   

15.
Capsule Population sizes of Common Guillemots Uria aalge, Razorbills Alca torda and Lesser Black‐backed Gulls Larus fuscus were associated with prey abundance but not prey quality.

Aims To examine how the abundance and quality of prey fish affects seabird population size and to test the ‘junk‐food’ or nutritional stress hypothesis.

Methods Analysis of long‐term seabird population size data and Sprat Sprattus sprattus biomass and age‐related weight data using a correlative approach.

Results De‐trended seabird and Sprat population data showed that the abundance of Sprat, the main prey species, was associated with the abundance of seabirds, while no effect of age‐related size of prey on seabird population size was found.

Conclusion As the Sprat population increased so did the seabird populations, regardless of decreases in ‘quality’ of Sprats, implying that more prey fish simply seem to mean more food in this marine ecosystem. No support for the ‘junk‐food’ hypothesis was found and the results contradict suggestions from earlier studies that prey quality is important to top‐predators in the Baltic Sea.  相似文献   

16.
Capsule Expert‐based classification of bird species as habitat specialists and as generalists agrees with objective measures of species’ habitat requirements based on large‐scale monitoring data.

Aims To compare habitat specialization of 137 common bird species breeding in the Czech Republic using three different measures and to test their relationships to species’ abundance and habitat associations.

Methods Data on bird abundance and surveyed habitats were collected through a standardized monitoring scheme of common breeding species in the Czech Republic. From these data we calculated a quantitative species specialization index (SSI). Canonical correspondence analysis (CCA) was applied to calculate species’ habitat niche breadth and the level of association of each species to the main habitats. A panel of 11 local bird experts classified each species as habitat generalist or habitat specialist.

Results Species classified as habitat specialists by expert opinion showed higher habitat specialization according to the SSI, as well as according to CCA‐based habitat niche breadth. These species were also more closely associated with one of the main habitat types. These relationships were significant even after controlling for abundance.

Conclusions As expert opinion accords with the level of species’ habitat specialization expressed using two quantitative objective measures, we suggest that these characteristics reflect real interspecific variation in the breadth of habitat requirements in birds. Interspecific differences in habitat specialization are not caused solely by the variability in abundance among species.  相似文献   

17.
Synthesis of “reversed” methylenecyclopropane analogues of nucleoside phosphonates 6a,7a, 6b, and 7b is described. 1-Bromo-1-bromomethylcyclopropane 8 was converted to the bromocyclopropyl phosphonate 9 by Michaelis-Arbuzov reaction with triisopropyl phosphite. Base-catalyzed β-elimination and deacetylation gave the key Z- and E-hydroxymethylcyclopropyl phosphonates 10 and 11 separated by chromatography. The Mitsunobu type of alkylation of 10 or 11 with adenine or 2-amino-6-chloropurine afforded phosphonates 12a, 12b, 13a, and 13b. Acid hydrolysis furnished the adenine and guanine analogues 6a, 7a, 6b, and 7b. The E and Z configuration was assigned on the basis of NOE experiments with phosphonates 6b and 7b. All Z- and E-isomers were also distinguished by different chemical shifts of CH2O or CH2N (H4 or H4′). Significant differences of the chemical shifts of the cyclopropane C3(3’) carbons and coupling constants 3JP,C2(2’) or 3JP,C3(3’) selective for the Z- or E-isomers were also noted. Phosphonates 6a, 7a, 6b, and 7b are devoid of significant antiviral activity.  相似文献   

18.
《Endocrine practice》2007,13(2):159-163
ObjectiveTo report a case of Graves’ disease with concomitant sarcoidosis involving the thyroid gland.MethodsWe present the clinical, laboratory, imaging, and pathologic findings and describe the clinical course of a patient with Graves’ disease and sarcoidosis, who was unresponsive to propylthiouracil and radioiodine treatment.ResultsA 23-year-old woman presented with thyrotoxicosis and a large goiter. Laboratory studies and findings on thyroid uptake and scan were consistent with Graves’ disease. She was also found to have hilar lymph-adenopathy and hepatosplenomegaly. Despite treatment with antithyroid drugs and radioiodine therapy, her hyperthyroidism persisted. Surgical resection of the thyroid gland and 2 lymph nodes disclosed noncaseating granulomas, consistent with sarcoid.ConclusionAutoimmune endocrinopathies and, less commonly, thyroid autoimmune disease have been reported in patients with sarcoidosis. Similarities exist in the pathogenesis of these two conditions. Concomitant sarcoidosis in the thyroid gland in patients with Graves’ disease may contribute to the resistance to antithyroid drugs and radioiodine therapy. (Endocr Pract. 2007;13:159-163)  相似文献   

19.
A l’occasion de la découverte d’une nouvelle espèce marocaine d’Apteranillus Fairmaire 1854: Apteranillus bichaini n. sp. provenant de l’extrémité occidentale de la chaîne de l’Atlas, de la découverte d’une nouvelle localité d’Apteranillus minosianus Lecoq & Quéinnec 2005 et de la capture du mâle de Typhlozyras camusi Jeannel 1960 jusqu’alors inconnu, toutes les espèces des genres Apteranillus, Typhlozyras et Apteraphaenops Jeannel 1907 sont redécrites et illustrées. Un tableau de détermination et une carte de répartition des genres et des espèces endogées et troglobies d’Aleocharinae d’Afrique du nord (Apteranillus, Anopsapterus, Drusilla (Apteranopsis), Apteraphaenops, Typhlozyras) sont donnés. La synonymie Apteranillus championi Bernhauer 1936=Apteranillus dohrnii Fairmaire 1854 n. syn. est établie. L’examen détaillé des caractères morphologiques des genres Typhlozyras et Apteraphaenops suggère l’appartenance de ces deux genres aux Athetini et non aux Lomechusini comme il est couramment admis jusqu’à présent, Apteraphaenops étant étroitement apparenté à Paraleptusa Peyerimhoff1901 et Typhlozyras à Geostiba Thomson 1858.  相似文献   

20.
Aim: To establish whether platelets from fragile X syndrome (FXS) individuals recapitulate FXS mouse neurons’ defects in ERK and Akt pathways, and to evaluate the effect of lovastatin on these pathways.

Methods: ERK and Akt phosphorylation (pERK, pAkt) statuses were assessed with quantitative Western blotting before and after a 12-week lovastatin trial.

Results: Levels of pERK and pAkt were increased in FXS platelets, and lovastatin specifically normalized ERK activity. Changes in ERK phosphorylation were correlated with clinical response to lovastatin.

Conclusions: Platelets’ signaling pathways provide biomarkers that can be used as treatment outcome measures in FXS clinical trials.  相似文献   

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