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1.
Infect Drug Resist ; 16: 4965-4975, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37546368

RESUMO

Purpose: The hyperproliferation of C. acnes has long been regarded as a primary etiological factor in the development of acne vulgaris (AV). Antibiotics targeting C. acnes have been the mainstay in AV treatment. Meanwhile, C. acnes has developed resistance to numerous antibiotics. IDDS, as traditional Chinese medicine, exhibits potent antibacterial activity against C. acnes. However, the mechanism of IDDS against C. acnes remains unclear. Methods: In this study, we conducted a systematic investigation in vitro to determine the minimal bactericidal concentration (MBC) and time-kill curves. The MBC and time-kill curves were assessed by quantifying Colony Forming Units countsIn order to establish an in vivo rat ear model of acne, a single intradermal injection of 100µL C. acnes suspension was administered, and oleic acid was applied to the right ear pinna for a duration of 14 days. The intervention involved the utilization of IDDS medications. Additionally, the levels of inflammatory mediators tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-10 (IL-10) were assessed using respective ELISA kits, while Hematoxylin and eosin (HE) staining was employed to visualize the rat ear model. The antimicrobial mechanism was investigated through the analysis of mRNA levels using real-time, quantitative PCR. ELISA analysis was performed according to the protocols outlined for energy metabolism and antioxidant system. Results: Our research has demonstrated that IDDS possesses antibacterial activity against C. acnes both in vitro and in vivo. The mechanisms underlying these effects involve energy metabolism and antioxidant systems. Conclusion: The data has provided further insights into the mechanism of IDDS against C. acnes, which establishes a robust foundation for the clinical application of IDDS.

2.
Microsc Res Tech ; 86(1): 12-27, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36318186

RESUMO

Baryscapus dioryctriae is an endoparasitic wasp in the pupae of many Pyralidae pests, such as Dioryctria mendacella, Ostrinia furnacalis, and Chilo suppressalis. To provide requisite background for our ongoing research on the mechanisms of host location in B. dioryctriae, the morphology, abundance, distribution, and ultrastructure of the antennal sensilla were investigated using scanning and transmission electron microscopy. The geniculate antennae of B. dioryctriae are composed of scape, pedicel, and flagellum. Eight types of sensilla including Böhm sensilla, chaetica, trichodea, basiconic capitate peg, campaniformia, placodea, coeloconica, and sensilla styloconicum with a long hair were identified on both sexes. Sexual dimorphism exists in the antennae of B. dioryctriae. The number of flagellomere in males is over females, and the subtypes and abundance of sensilla are also different between the sexes. Additionally, the possible functions of distinct sensilla were discussed, which varies from olfaction, contact chemoreceptive, mechanoreception to hygro-/thermoreception, especially, the sensilla trichodea and placodea might be involved in olfactory perception in B. dioryctriae. These results provide an essential basis for further study on chemical communication between B. dioryctriae and their hosts, and contribute to the development of B. dioryctriae becoming an effective biocontrol agent against the pests of agriculture and forestry.


Assuntos
Himenópteros , Vespas , Animais , Feminino , Masculino , Himenópteros/ultraestrutura , Sensilas/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Caracteres Sexuais , Antenas de Artrópodes/ultraestrutura
3.
Plant J ; 109(6): 1375-1385, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34905264

RESUMO

Slow development has been shown to be a general mechanism to restore the fertility of thermo-sensitive and photoperiod-sensitive genic male sterile (TGMS and PGMS) lines in Arabidopsis. rpg1 is a TGMS line defective in primexine, which is essential for pollen wall pattern formation. Here, we showed that RPG1-GFP was highly expressed in microsporocytes, microspores, and pollen grains but not in the tapetum in the complemented transgenic line, suggesting that microsporocytes are the main sporophytic cells for primexine formation. Further cytological observations showed that primexine formation in rpg1 was partially restored under slow growth conditions, leading to its fertility restoration. RPG2 is the homolog of RPG1 in Arabidopsis. We revealed that the fertility recovery of rpg1 rpg2 was significantly reduced compared with that of rpg1 under low temperature. The RPG2-GFP protein was also expressed in microsporocytes in the RPG2-GFP (WT) transgenic line. These results suggest that RPG2 plays a redundant role in rpg1 fertility restoration. rpg1 plants were male sterile at the early growth stage, while their fertility was partially restored at the late developmental stage. The fertility of the rpg1 lateral branches was also partially restored. Further growth analysis showed that slow growth at the late reproductive stage or on the lateral branches led to fertility restoration. This work reveals the importance of gene redundancy in fertility restoration for TGMS lines and provides further insight into pollen wall pattern formation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fertilidade/genética , Infertilidade das Plantas/genética , Pólen/metabolismo
4.
Front Physiol ; 13: 1079328, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36714303

RESUMO

Introduction: Flight muscle histolysis, as an important survival strategy, is a widespread phenomenon in insects and facilitates adaptation to the external environment in various insect taxa. However, the regulatory mechanism underlying this phenomenon in Orthoptera remains unknown. Methods: In this study, the flight muscle histolysis in the house cricket Acheta domesticus was investigated by transcriptomics and RNA interference. Results: The results showed that flight muscle histolysis in A. domesticus was standard and peaked within 9 days after eclosion of adult crickets, and there was no significant difference in the peak time or morphology of flight muscle histolysis between males and females. In addition, the differentially expressed genes between before and after flight muscle histolysis were studied, of which AdomFABP, AdomTroponin T and AdomActin were identified as candidate genes, and after injecting the dsRNA of these three candidates, only the downregulated expression of AdomFABP led to flight muscle histolysis in A. domesticus. Furthermore, the expression level of AdomFABP was compared between before and after flight muscle histolysis based on RT-qPCR. Disscussion: We speculated that AdomFABP might play a role in the degradation of flight muscle by inhibiting muscle development. Our findings laid a molecular foundation for understanding the flight muscle histolysis.

5.
Plant Physiol ; 184(2): 923-932, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32796091

RESUMO

Photoperiod- and thermosensitive genic male sterility (P/TGMS) lines are widely used in crop breeding. The fertility conversion of Arabidopsis (Arabidopsis thaliana) TGMS lines including cals5-2, which is defective in callose wall formation, relies on slow development under low temperatures. In this study, we discovered that cals5-2 also exhibits PGMS. Fertility of cals5-2 was restored when pollen development was slowed under short-day photoperiods or low light intensity, suggesting that slow development restores the fertility of cals5-2 under these conditions. We found that several other TGMS lines with defects in pollen wall formation also exhibited PGMS characteristics. This similarity indicates that slow development is a general mechanism of PGMS fertility restoration. Notably, slow development also underlies the fertility recovery of TGMS lines. Further analysis revealed the pollen wall features during the formation of functional pollens of these P/TGMS lines under permissive conditions. We conclude that slow development is a general mechanism for fertility restoration of P/TGMS lines and allows these plants to take different strategies to overcome pollen formation defects.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Fotoperíodo , Infertilidade das Plantas/genética , Infertilidade das Plantas/fisiologia , Pólen/crescimento & desenvolvimento , Pólen/genética , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo
6.
J Chromatogr Sci ; 44(6): 324-32, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16884587

RESUMO

Solid-phase microextraction (SPME) has been popular as an environmentally friendly sample pretreatment technique to extract a very wide range of analytes. This is partly owing to the development of SPME coatings. One of the key factors affecting the extraction performances, such as the sensitivity, selectivity, and reproducibility, is the properties of the coatings on SPME fibers. This paper classifies the materials used as SPME coatings and introduces some common preparation techniques of SPME coating in detail, such as sol-gel technique, electrochemical polymerization technique, particle direct pasting technique, restricted access matrix SPME technique, and molecularly imprinted SPME technique.


Assuntos
Técnicas Eletroquímicas/métodos , Microextração em Fase Sólida/métodos , Celulose/análogos & derivados , Celulose/química , Cobre/química , Grafite/química , Poliaminas/química , Polimerização , Polímeros/química , Cloreto de Polivinila/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Siloxanas/química
7.
Anal Sci ; 21(11): 1343-7, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16317903

RESUMO

Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography/mass spectrometry (GC/MS) method was developed to determine 3-chloropropane-1,2-diol (3-MCPD) in hydrolyzed vegetable protein and Chinese soy sauce. The 3-MCPD was firstly derivativized with phenylboronic acid in aqueous solution at 90 degrees C for 10 min, then extracted by HS-SPME and finally detected with GC/MS, parameters related to both the derivative reaction and the HS-SPME process were optimized. The proposed method has a linear range of 0.0194-394 microg g(-1), a detection limit of 3.87 ng g(-1) (S/N = 3), and a precision of RSD = 7.5% (n = 5). Seventeen real samples, including four HVPs and thirteen soy sauce samples, were analyzed to examine the feasibility of the proposed procedure; with a concentration of 3-MCPD and acceptable recoveries at 0.71 microg g(-1) spiked levels were obtained. Being simpler, faster and more environmentally benign than the existing methods, this method is accurate and suitable for routine analysis.


Assuntos
Proteínas de Vegetais Comestíveis/análise , Alimentos de Soja/análise , alfa-Cloridrina/análise , Ácidos Borônicos/química , Cromatografia Gasosa-Espectrometria de Massas , Hidrólise , Imidazóis/química , Reprodutibilidade dos Testes , Cloreto de Sódio/química , Temperatura , alfa-Cloridrina/química
8.
J Sep Sci ; 28(16): 2218-24, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16318220

RESUMO

For SPME-HPLC, metal wires with better mechanical strength are preferred over the fused silica fibers. In this article, a novel composite polyaniline (CPANI) doped with PEG and polydimethylsiloxane coating (CPANI fiber) was prepared on a stainless steel wire by a three-electrode system: the fiber was used as the work electrode, a calomel electrode and a platinum electrode were used as the reference and the counter electrodes, respectively. To evaluate the new CPANI coating, the coating was used to extract three kinds of phenols (bisphenol A, 4-n-nonylphenol, and 4-tert-octylphenol) in water samples by direct-SPME mode and then desorbed in commercial SPME-HPLC interface to separation. The extraction procedure was also optimized. Five real water samples were investigated. Good recoveries were gained when environmental samples were analyzed.


Assuntos
Compostos de Anilina/síntese química , Cromatografia Líquida de Alta Pressão , Fenóis/análise , Compostos Benzidrílicos , Cromatografia Líquida de Alta Pressão/instrumentação , Dimetilpolisiloxanos , Concentração de Íons de Hidrogênio , Polietilenoglicóis , Rios/química , Silicones , Cloreto de Sódio
9.
J Chromatogr A ; 1072(1): 3-6, 2005 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-15881452

RESUMO

Based on the non-volatility of room temperature ionic liquids (IL), 1-butyl-3-methylimidazolium hexafluorophosphate ([C4MIM][PF6]) IL was employed as an advantageous extraction solvent for high temperature headspace liquid-phase microextraction (LPME) of chloroanilines in environmental water samples. At high temperature of 90 degrees C, 4-chloroaniline, 2-chloroaniline, 3,4-dichloroaniline, and 2,4-dichloroaniline were extracted into a 10 microl drop of [C4MIM][PF6] suspended on the needle of a high-performance liquid chromatography (HPLC) microsyringe held at the headspace of the samples. Then, the IL was injected directly into the HPLC system for determination. Parameters related to LPME were optimized, and high selectivity and low detection limits of the four chlorinated anilines were obtained because the extraction was performed at high temperature in headspace mode and the very high affinity between IL and chlorinated anilines. The proposed procedure was applied for the analysis of the real samples including tap water, river water and wastewater samples from a petrochemical plant and a printworks, and only 3,4-dichloroaniline was detected in the printworks wastewater at 88.2 microg l(-1) level. The recoveries for the four chlorinated anilines in the four samples were all in the range of 81.9-99.6% at 25 microg l(-1) spiked level.


Assuntos
Compostos de Anilina/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Poluentes Químicos da Água/isolamento & purificação , Temperatura Alta , Concentração de Íons de Hidrogênio , Imidazóis , Microquímica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes
10.
Ying Yong Sheng Tai Xue Bao ; 16(11): 2130-4, 2005 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-16471353

RESUMO

Through investigation and by the methods of optimal partitioning, principal component analysis, and one-or two-dimensional ordination, this paper analyzed the main groups and succession trends of the pest and natural enemy communities at a jujube orchard of Taigu area. The results showed that the communities had more obvious dominant factors and temporal succession pattern. The first three principal components of the communities had a bigger variation, with an obvious follow effects. The community succession was temporally divided into four stages, i. e., in the periods of pre-budding, leaf expanding and blooming, fruiting, and maturing. The dominant species of pests and their natural enemies were demonstrated.


Assuntos
Ecossistema , Insetos/fisiologia , Comportamento Predatório/fisiologia , Ziziphus/parasitologia , Animais , China
11.
J Environ Sci (China) ; 17(6): 930-2, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16465880

RESUMO

Base on the previous work in laboratory, a novel polyaniline doped with polydimethylsiloxane coating was developed on a stainless steel wire for solid phase microextraction(SPME) by electroplating method. This electroplating method not only has advantages of ease preparation and simple equipments required, but also increases the lifetime of the SPME fiber. The composite fiber (polyaniline/ polydimethylsiloxane(PANI/PDMS)) was evaluated by analyzing n-tridecane, n-tetradecane and n-pentadecane in aqueous sample. The new fiber coating showed comprehensive abilities to extract alkanes compounds. The relative standard deviations were found to be 6.8%-10.33%.


Assuntos
Alcanos/análise , Compostos de Anilina/química , Dimetilpolisiloxanos/química , Galvanoplastia/métodos , Silicones/química , Poluentes Químicos da Água/análise , Purificação da Água/instrumentação , Cromatografia Gasosa , Microscopia Eletrônica de Varredura , Purificação da Água/métodos
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