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1.
Background: Propolis is a natural product of plant resins collected by honeybees from various plant sources. It is used as a remedy in folk medicine since ancient times because of its several biological and pharmacological properties. Recently, propolis has been used by dentist to treat various oral diseases. It was always mentioned as an anti-inflammatory agent. Cytokines are proteins that provide communication between cells and play a critical role in a wide variety of processes. It released from cells in an inflammatory process that active, mediate or potential actions of other cells or tissues. When dental pulp has inflammation, several pro-inflammatory cytokines including Interleukin-6 (IL-6) was released by innate immune cells. Objective: To analyse the expression of IL-6 on inflamed rat dental pulp tissue following application of propolis. Material and methods: Trigona sp. propolis was obtained from Luwu Regency, south Sulawesi Province, Indonesia. Flavonoid and non-flavonoid extracts were purified from propolis using thin layer chromatography. The study was applied on 80 male Sprague Dawley rats, 10–12 weeks of age, divided randomly and equally into 5 groups. Group I, as negative control group was not conducted any treatment. At group II, III, IV and V. A Class I cavity (Black Classification) were made on the occlusal surface of right maxillary first molar. The dental pulp was perforated using dental explorer and allowed in the oral environment for 1 h, after that, Ethanolic Extract Propolis (EEP) (Group II), Extract Flavonoid-Propolis (EFP) (Group III), Extract Non-Flavonoid Propolis (ENFP) (Group IV), or Calcium Hydroxide (Ca(OH)2) (Group V) were applied on dental pulp. All cavities were then filled with Glass Ionomer Cement as permanent filling. The rats being sacrificed in 6 h, 2 days, 4 days and 7 days. Sample biopsy were obtained, IL-6 expression was detected by using immunohistochemistry method. Data was analyzed statistically using Freidman and Kruskal Wallis tests with significance level of P < 0.05. Results: All agent showed IL-6 expression in inflamed rat dental pulp tissue, and this expression was decreased with the longer of observation time periods. EEP more stronger to decreased IL-6 expression on inflamed rat dental pulp tissue than other agent. There is significant difference (P < 0.05) of IL-6 expression between group I and other groups in 6 h and 2 days but not in 4 and 7 days time periods. Conclusion: Trigona sp. propolis from south Sulawesi, Indonesia could suppressed the expression of IL-6 on inflamed rat dental pulp tissue.  相似文献   
2.
Biosynthesis and Genetic Engineering of Lignin   总被引:1,自引:0,他引:1  
Lignin, a complex heteropolymer of cinnamyl alcohols, is, second to cellulose, the most abundant biopolymer on Earth. Lignification has played a determining role in the adaptation of plants to terrestrial life. As all extracellular polymers, lignin confers rheological properties to plant tissues and participates probably in many other functions in cell and tissue physiology orin cell-to-cell communication. Economically, lignin is very important because it determines wood quality and it affects the pulp and paper-making processes as well as the digestibility of forage crops. For all these reasons the lignin biosynthesis pathway has been the subject of many studies. At present, most genes encoding the enzymes involved in the biosynthesis of lignin have been cloned and characterized. Various recent studies report on the alteration of the expression of these genes by genetic engineering, yielding plants with modified lignin. In addition, several mutants have been analyzed with changes in lignin content or lignin composition resulting in altered properties. Thanks to these studies, progress in the knowledge of the lignin biosynthesis pathway has been obtained. It is now clear that the pathway is more complex than initially thought and there is evidence for alternative pathways. A fine manipulation of the lignin content and/or composition in plants is now achievable and could have important economical and environmental benefits.  相似文献   
3.
4.
An α-glucosidase was purified from sweet corn seeds by fractionation with ammonium sulfate, chromatographies on CM-Sepharose and Sepharose 4B, and gel filtrations on Sephadex G-100. The enzyme was homogeneous in disc electrophoretic analysis. The molecular weight was estimated to be about 9.6 × 104 by SDS-disc electrophoresis.

The enzyme showed high activities toward maltose, nigerose, phenyl-α-maltoside, and maltooligosaccharides. The ratios of maximum velocity for maltose, nigerose, kojibiose, isomaltose, phenyl-α-glucoside, phenyl-α-maltoside, panose, turanose, and soluble starch were estimated to be 100 : 78 : 17 : 11 : 28 : 100 : 31 : 3.4 : 126, and the Km values for these substrates, 1.5 mM, 1.4 mM, 0.48 mM, 14 mM, 4.2 mM, 1.1 mM, 5.0 mM, 0.28 mM and 52mg/ml, respectively. The maximum velocity for soluble starch was high, but this α-glucan was not a favorable substrate because the Km value was also very high. The Vmax for maltooligosaccharides were somewhat dependent on the degree of polymerization (n). The Km values for substrates having four or more glucose units increased with the increase in n.  相似文献   
5.
Three 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP)-mineralizing bacteria were isolated from the secondary sludge of a pulp and paper industry. The isolates used 2,3,4,6-TeCP as a source of carbon and energy and were capable of degrading this compound, as indicated by stoichiometric release of chloride and biomass formation. Based on 16S rRNA gene sequence analysis, the bacteria were identified as Bacillus megaterium (CL3), Staphylococcus suciri (CL10), and Bacillus thuringensis (CL11). High-performance liquid chromatography (HPLC) analysis revealed that these isolates were able to degrade 2,3,4,6-TeCP at higher concentrations (600 mg/L or 2.5 mM). A consortia of the isolates completely removed 2,3,4,6-TeCP from the sludge obtained from a pulp and paper mill within 2 weeks when supplemented at a rate of 100 mg/L or 0.43 mM. A bacterial consortium also significantly reduced absorbable organic halogen (AOX) and extractable organic halogen (EOX) by 63% and 68%, respectively, from the sludge. These isolates have a high potential to remove 2,3,4,6-TeCP and may be used for remediation of pulp paper mill waste containing 2,3,4,6-TeCP.  相似文献   
6.
Summary The distribution and origin of neurokinin A (NKA)-like immunoreactivity were investigated in feline dental pulp by an indirect immunofluorescence method. NKA-containing nerve fibres with varicosities, which entered the dental pulp via apical foramen, were distributed throughout this tissue. Many NKA-containing nerve fibres were localized around blood vessels, but some were observed apart therefrom. At the odontoblastic layer, thin NKA-containing nerve fibres were observed running straight toward the pulp-predentinal border between odontoblasts. After inferior alveolar nerve section, all NKA-containing nerve fibres disappeared in the dental pulp, while the removal of the superior cervial ganglion resulted in no change in the distribution of these fibres. The correlation of NKA-like immunoreactivity and substance P (SP)-like immunoreactivity was also investigated by double-immunofluorescence technique. The distribution of NKA-containing nerve fibres was very similar to that of SP-containing nerve fibres; it appeared that all NKA-containing nerve fibres contained SP.  相似文献   
7.
The behaviour of different hardwood glucuronoxylans during the kraft pulping process was investigated. Woods and pulps xylans were isolated and characterized by size exclusion chromatography, methylation (linkage) analysis and 1H NMR. Eucalyptus globulus and Eucalyptus urograndis showed xylan retention significantly higher than that of Betula pendula. The higher retention of Eucalyptus xylans was assigned to (i) their higher average molecular weight (31 against 24 KDa in B. pendula) and to (ii) the presence of O-2 substituted 4-O-methyl--d-glucuronic acid groups ([→2)-GlcpA-(1→]) with galactopyranosyl/glucopyranosyl residues belonging to fragments of galactan/glucan chains that were absent in B. pendula xylans. A significant part of uronic acids, particularly [→2)-GlcpA-(1→] units, remain in fibres until the end of pulping. The acetylation degree and distribution of acetyl groups between Xylp units, in general terms, was similar in the three types of xylans. Unexpectedly, about 20% of the acetyl groups persisted in pulps xylans till the end of pulping.  相似文献   
8.
解磷微生物的研究进展   总被引:18,自引:0,他引:18  
磷是植物生长必需的矿质元素之一,而土壤中可溶性磷的含量比较低。土壤中有大量的微生物存在,其中有一些微生物能够将土壤中的不溶性磷转化成可溶性磷,主要对解磷微生物的种类、数量、分布、解磷机制及应用方面的有关情况进行综述。  相似文献   
9.
Transganglionic transport of horseradish peroxidase conjugated to wheatgerm agglutinin (HRP:WGA) entrapped in hypoallergenic polyacrylamide gel was used to study the patterns of termination of primary afferents that innervate the upper and lower tooth pulps within the trigeminal sensory nuclear complex (TSNC) of the monkey. HRP:WGA injections were also made into the lower incisors and molars, in order to examine the topographic arrangement of pulpal afferent projections. HRP-labeled pulpal afferents innervating lower and upper teeth projected ipsilaterally to the rostral subnucleus dorsalis (Vpd) and caudal subnucleus ventralis (Vpv) of the nucleus principalis (Vp); the rostrodorsomedial (Vo.r) and dorsomedial (Vo.dm) subdivisions of the nucleus oralis (Vo); the dorsomedial subdivision of the nucleus interpolaris (Vi); and laminae I—II and/or V of the nucleus caudalis (Vc) at its rostralmost level. The HRP-labeled terminals from upper and lower pulpal afferents formed a rostrocaudal column from the midlevel of Vp to the rostral tip of Vc. The label in Vp and Vo was considerably dense, but the column of terminals was interrupted at the Vpd-Vpv transition. The label in Vi and Vc was much less dense compared to that in the rostral nuclei, and the column of terminals was interrupted frequently. The representation of the upper and lower teeth in TSNC was organized in a somatotopic fashion that varied from one subdivision to the next, though their terminal zones overlapped within Vpd. The upper and lower teeth were represented in Vpv, Vo.r, Vo.dm, Vi, and Vc in a ventrodorsal, dorsoventral, lateromedial, lateromedial, and lateromedial sequence, respectively. Topographic arrangement was also noticed for the projections of pulpal afferents from the lower incisors and molars: The representations of the lower incisors and molars in Vpv, Vo.r, Vo.dm, Vi, and Vc were organized in a lateromedial, dorsoventral, ventrodorsal, ventrodorsal, and lateromedial sequence, respectively. The present results indicating sparse projections from pulpal afferents in the monkey's Vc are in good correspondence with a clinical report that trigeminal tractotomy just rostral to the obex has no significant effect on dental pain perception in patients. Furthermore, the present study indicates that projection patterns of pulpal afferents—which include the termination sites, the density of terminations between nuclei, and topographic arrangement—differ among animal species.  相似文献   
10.
From high-CO2 (5% CO2) grown unicellular green alga, Chlamydomonas reinhardtii, carbonic anhydrase (CA) was isolated by affinity chromatography and characterized. Isolated CA was identified as an isozyme (CA2) which is the product from the second gene CAH2 by peptide sequencing. The CA2 was inactivated by dithiothreitol. This treatment caused dissociation of CA2 into the large (38 kDa) and small subunits (4243 Da). The molecular mass of the CA2 holoenzyme measured by low-angle laser light-scattering photometry and precision differential refractometry combined with gel-filtration HPLC was 87.9 kDa. These results and gene structure indicate that CA2 is a heterotetramer consisting of two large and two small subunits linked by disulfide bonds like CA1, which is the CAH1 gene product. The speciffc activity of CA2 purified by anion-exchange HPLC was 3300 units per mg protein, which was approximately 1.6 times higher than that of CA1. Therefore, it was concluded that two structurally related isozymes, CA1 and CA2, are present in the wild type cells of C. reinhardtii and differentially regulated by the atmospheric CO2 concentration.  相似文献   
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