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61.

Main conclusion

Coleoptera, the largest and the most diverse Insecta order, is characterized by multiple adaptations to plant feeding. Insect-associated microorganisms can be important mediators and modulators of interactions between insects and plants. Interactions between plants and insects are highly complex and involve multiple factors. There are various defense mechanisms initiated by plants upon attack by herbivorous insects, including the development of morphological structures and the synthesis of toxic secondary metabolites and volatiles. In turn, herbivores have adapted to feeding on plants and further sophisticated adaptations to overcome plant responses may continue to evolve. Herbivorous insects may detoxify toxic phytocompounds, sequester poisonous plant factors, and alter their own overall gene expression pattern. Moreover, insects are associated with microbes, which not only considerably affect insects, but can also modify plant defense responses to the benefit of their host. Plants are also frequently associated with endophytes, which may act as bioinsecticides. Therefore, it is very important to consider the factors influencing the interaction between plants and insects. Herbivorous insects cause considerable damage to global crop production. Coleoptera is the largest and the most diverse order in the class Insecta. In this review, various aspects of the interactions among insects, microbes, and plants are described with a focus on coleopteran species, their bacterial symbionts, and their plant hosts to demonstrate that many factors contribute to the success of coleopteran herbivory.
  相似文献   
62.
New derivatives of two isomeric types of azaphenothiazines, 1,8- and 2,7-diazaphenothiazine, containing the triple bond substituents and additionally tertiary cyclic and acyclic amine groups, were synthesized and tested for their anticancer activity. The compounds exhibited differential inhibitory activities. Better results were obtained when the acetylenic group was transformed via the Mannich reaction to the dialkylaminobutynyl groups. The most active was 2,7-diazaphenothiazine with the N-methylpiperazine-2-butynyl substituent against the human ductal breast epithelial tumor cell line T47D, more potent than cisplatin. The 2,7-diazaphenothiazine system turned out to be more active than isomeric 1,8-diaza one. For the most active compound, the expression of TP53, CDKN1A, BCL-2 and BAX genes was detected by the RT-QPCR method. The gene expression ratio BACL-2/BAX suggests the mitochondrial apoptosis in T47D cells. The synthesis makes possible to obtain many new bioactive phenothiazines with the dialkylaminoalkynyl substituents inserting various tertiary cyclic and acyclic amine moieties to the substituents.  相似文献   
63.
A bioautographic assay based on thin layer chromatography was developed for phosphoenolpyruvate (PEP) detecting as a known but rarely studied inhibitor of phosphoglucose isomerase (PGI). The protocol with NADP+/NBT/PMS (β-nicotinamide adenine dinucleotide phosphate/nitrotetrazolium blue chloride/phenazine methosulfate) staining was capable of detecting Mycobacterium tuberculosis H37Ra PGI inhibition using PEP. According to this method, visibly brighter spots (zones) against purple background are observed in the area of inhibition of the above-mentioned enzyme activity. The detection limit for PEP as an inhibitor of Mycobacterium tuberculosis H37Ra PGI was 226?μg per spot/zone. Noteworthy is that we are the first authors to have successfully used a bioautographic assay to detect Mycobacterium tuberculosis H37Ra PGI inhibition by PEP.  相似文献   
64.

Introduction

Human primary cells originating from different locations within the body could differ greatly in their metabolic phenotypes, influencing both how they act during physiological/pathological processes and how susceptible/resistant they are to a variety of disease risk factors. A novel way to monitor cellular metabolism is through cell energetics assays, so we explored this approach with human primary cell types, as models of sclerotic disorders.

Objectives

In order to better understand pathophysiological processes at the cellular level, our goals were to measure metabolic pathway activities of endothelial cells and fibroblasts, and determine their metabolic phenotype profiles.

Methods

Biolog Phenotype MicroArray? technology was used for the first time to characterize metabolic phenotypes of diverse primary cells. These colorimetric assays enable detection of utilization of 367 specific biochemical substrates by human endothelial cells from the coronary artery (HCAEC), umbilical vein (HUVEC) and normal, healthy lung fibroblasts (NHLF).

Results

Adenosine, inosine, d-mannose and dextrin were strongly utilized by all three cell types, comparable to glucose. Substrates metabolized solely by HCAEC were mannan, pectin, gelatin and prevalently tricarballylic acid. HUVEC did not show any uniquely metabolized substrates whereas NHLF exhibited strong utilization of sugars and carboxylic acids along with amino acids and peptides.

Conclusion

Taken together, we show for the first time that this simple energetics assay platform enables metabolic characterization of primary cells and that each of the three human cell types examined gives a unique and distinguishable profile.
  相似文献   
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Background: There is barely any evidence of antipsychotic drugs affecting the molecular clockwork in human, yet it is suggested that clock genes are associated with dopaminergic transmission, i.e. the main target of this therapeutics. We decided to verify if haloperidol and olanzapine affect expression of CLOCK, BMAL1, PER1 and CRY1 in a human central nervous system cell line model. Methods: U-87MG human glioblastoma cell line was used as an experimental model. The cells were incubated with or without haloperidol and olanzapine in the concentration of 5 and 20 μM for 24 h. Real-time quantitative polymerase chain reaction with the ΔCT analysis was used to examine the effect of haloperidol and olanzapine on the mRNA expression of the genes. Results: At 5 μM, haloperidol decreased expression of CRY1 almost 20-fold. There was nearly a 1.5-fold increase in expression of PER1. Considering the 20 μM haloperidol concentration and both olanzapine concentrations, no other statistically significant effect was observed. Conclusions: At certain concentration, haloperidol seems to affect expression of particular clock genes in a human central nervous system cell line model, yet mechanism underlying this phenomenon remains elusive.  相似文献   
68.
Pain in patients with hip osteoarthritis appears long before surgery, and requires effective management as it affects patient comfort and daily activities. Therefore, the search for factors influencing response rate to analgesics is mandatory. In recent years, increasing attention has been paid to genetic factors underlying pain threshold and treatment efficacy. Polymorphic gene of catechol-oxide-methyltransferase (COMT) is a candidate gene associated with pain pathology and treatment response. The aim of the study was to evaluate association between the COMT rs4680:G>A polymorphism and demand for analgesics in patients subjected to elective hip replacement. The study included 196 patients after hip replacement surgery. Opioid demand was recorded and analgesic efficacy was scored using a four-level verbal pain intensity scale. COMT rs4680:G>A polymorphism was analysed by PCR-RFLP method. The studied COMT genotypes did not influence opioid administration in the studied patients from the day of surgery till day 6 afterwards. The distribution of the COMT rs4680:G>A in the studied subjects was as follows: GA—52.04%, AA—23.98% and GG—23.98%. It can be concluded that the COMT rs4680:G>A polymorphism is not associated with opioid demand in patients after elective hip replacement.  相似文献   
69.
70.
The aim of the study was the assessment of the ability of short peptides to form aggregates under physiological conditions. The dipeptides studied were derived from different aromatic amino acids (heteroaromatic peptides). Tripeptides were obtained from two distinct aromatic amino acids and cysteine or methionine residue in the C‐terminal, N‐terminal, or central position. The ability of the peptides to form fibrous aggregates under physiological conditions was evaluated using three independent methods: the Congo Red assay, the Thioflavin T assay, and microscopic examinations using normal and polarized light. Materials potentially useful for regenerative medicine were selected based on their cytotoxicity to the endothelial cell line EA.hy 926 and physicochemical properties of films formed by peptides. The required parameters of biocompatibility were fulfilled by H?PheCysTrp?OH, H?PheCysTyr?OH, H?PheTyrMet?OH, and H?TrpTyr?OH.  相似文献   
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