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61.
62.
摘要 目的:探讨2型糖尿病(T2DM)伴慢性牙周炎(CP)患者龈沟液网膜素-1(Omentin-1)、基质金属蛋白酶-9(MMP-9)、骨保护素(OPG)/细胞核因子κB受体活化因子配体(RANKL)比值与牙周指标、氧化应激和核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)炎症小体的关系。方法:选择2020年6月至2022年6月首都医科大学附属北京康复医院收治的73例T2DM患者(T2DM组),77例CP患者(CP组),83例T2DM伴CP患者(T2DM伴CP组)。检测所有患者龈沟液中Omentin-1、MMP-9、OPG/RANKL比值,分析其与牙周指标、氧化应激和NLRP3炎症小体相关分子信使核糖核酸(mRNA)表达的相关性。结果:T2DM伴CP组龈沟液中Omentin-1,OPG/RANKL比值、总抗氧化能力(TAC)、超氧化物歧化酶(SOD)低于T2DM组和CP组(P<0.05),MMP-9、丙二醛(MDA)、NLRP3mRNA、凋亡相关斑点样蛋白(ASC)mRNA、半胱氨酸蛋白酶-1(caspase-1)mRNA表达以及出血指数(SBI)、菌斑指数(PLI)、牙周袋探诊深度(PD)、附着丧失(AL)高于T2DM组和CP组(P<0.05)。T2DM伴CP患者龈沟液中Omentin-1、OPG/RANKL比值与TAC、SOD呈正相关(P<0.05),与MDA、NLRP3mRNA、ASC mRNA、caspase-1mRNA表达以及PLI、SBI、AL、PD呈负相关(P<0.05),MMP-9与TAC、SOD呈负相关(P<0.05),与MDA、NLRP3mRNA、ASC mRNA、caspase-1mRNA表达以及PLI、SBI、AL、PD呈正相关(P<0.05)。结论:T2DM伴CP患者龈沟液中Omentin-1水平、OPG/ RANKL比值降低,MMP-9水平升高,与牙周组织破坏加重、氧化应激、NLRP3炎症小体激活有关。  相似文献   
63.
Cessation of shoot elongation in seedlings of Salix pentandra L. is induced by short photoperiod. Gibbereliin A9 (GA9) applied either to the apical bud or injected into a mature leaf, induced shoot elongation under a short photoperiod of 12 h, and GA9 could completely substitute for a transfer to a long photoperiod. When [3H]GA9 or [2H2]GA9 was injected into a leaf, no [3H]GA9 was detected in the elongating apex and only traces of [3H]GA9 were found in the shoot above the treated leaf. By the use of gas chromatography-mass spectrometry (GC-MS), [2H2]GA20 was identified as the main metabolite of [2H2]GA9 in both the shoot and the treated leaf. In addition, [2H2]GA1 and [2H2]GA29 were also identified as metabolites of [2H2]GA9. These results are consistent with the hypothesis that exogenous GA, promotes shoot elongation in Salix through its metabolism to GA20 and GA,.  相似文献   
64.
The action of rotameric probes introduced either in position 7 or 8 in the sequence of substance P (SP) was investigated, i.e. -tetrahydroisoquinoleic acid (Tic), -fluorenylglycine (Flg), -diphenylalanine (Dip), the diastereoisomers of -1-indanylglycine (Ing) and -benz[ƒ]indanylglycine (Bfi), the Z- and E-isomers of dehydrophenylalanine and dehydronaphthylalanine (ΔZPhe, ΔEPhe, ΔZNal, ΔENal) and (Dmp). The aim of this study was the topographical characterization of the binding subsites of human NK-1 receptor expressed in CHO cells, especially the S7 and S8 subsites, corresponding to residues Phe7 and Phe8 of substance P. According to the binding potencies of these substituted-SP analogues, the S7 binding subsite is smaller than the S8 subsite: the S7 subsite accepts only one aromatic nucleus, while the S8 can accommodate three coplanar nuclei altogether. These findings are compatible with the idea that the S8 binding subsite may reside in the extracellular loops of the hNK-1 receptor. NK-1 agonists bind to human NK-1 receptor and activate the production of both inositol phosphates and cyclic AMP. As already quoted for septide, [pGlu6, Pro9]SP(6–11), discrepancies are observed between affinity (Ki) and activity (EC50) values for IPs production. While a weak correlation between Ki and EC50 values for IPs production could be found (r = 0.70), an excellent correlation could be demonstrated between their affinities (Ki) and their potencies (EC50) for cAMP production (r = 0.97). The high potency (EC50) observed for ‘septide-like’ molecules on PI hydrolysis, compared to their affinity is not an artefact related to the high level of NK-1 receptors expressed on CHO cells since a good correlation was found between EC50 values obtained for PI hydrolysis and those measured for spasmogenic activity in guinea pig ileum bioassay (r = 0.94).

According to the binding potencies of constrained analogues of phenylalanine, the S7 binding subsite of human NK-1 receptor is small, whereas the S8, which can accommodate three coplanar nuclei, might probably reside in the extracellular loop. The discrepancies observed between affinity (Ki) and activity (EC50) values for IPs production are not an artefact of CHO cells since a good correlation was found between EC50 for PI hydrolysis and those measured in guinea pig ileum bioassay.  相似文献   

65.
66.
The growth of the Spodoptera frugiperda cell line Sf9 was studied in batch and continuous culture. The results of batch cultivations showed that glucose was the preferred energy and carbon source limiting the cell density in both TNM-FH and IPL-41 media. Continuous culture using IPL-41-based feeding medium with different glucose (2.5, 5 and 10 g l−1) and yeast extract concentrations (4, 8 and 16 g l−1) showed that in serum-supplemented medium the maximum cell density was limited by glucose and yeast extract concentration. The transition to glucose limitation caused a decrease in growth rate and viability. A high cell density culture (18 × 106 ml−1) was obtained using a glucose concentration of 10 g l−1 and a yeast extract concentration of 8 g l−1 in the feeding medium. A yeast extract concentration of 16 g l−1 inhibited growth. Unlike mammalian cell cultures, lactate, alanine and ammonia were not involved in growth inhibition. Lactate did not accumulate under aerobic conditions. Ammonia accumulation, if observed, was insignificant. The level of alanine synthesized and excreted into the culture medium never reached an inhibitory level. During glucose limitation alanine did not accumulate and ammonia was released. However, even in the presence of glucose significant amounts of Asp, Glu, Gln, Asn, Ser, Arg and Met were utilized for energy production. The amino groups of these amino acids were transferred to pyruvate or used for nucleic acid synthesis and excreted in the form of alanine into the culture medium. The consumption of His, Lys, Thr, Gly, Val, Leu, Phe, Tyr, Trp and Ile by growing Sf-9 cells was almost equal to their concentration in the biomass.  相似文献   
67.
A study was undertaken to assess the role of a physiological concentration of glutamine in AS-30D cell metabolism. Flux of14C-glutamine to14CO2 and of14C-acetate to glutamate was detected indicating reversible flux between glutamate and TCA cycle -ketoglutarate. These fluxes were transaminase dependent. A flux analysis was compared using data from three tracers that label -ketoglutarate carbon 5, [2-14C]glucose, [1-14C]acetate and [5-14C]glutamine. The analysis indicated that the probability of flux of TCA cycle -ketoglutarate to glutamate was, at minimum, only slightly less than the probability of flux of -ketoglutarate through -ketoglutarate dehydrogenase. The apparent Km for oxidative flux of [14C]glutamine to14CO2, 0.07 mM, indicated that this flux was at a maximal rate at physiological, 0.75 mM, glutamine. Although oxidative flux through -ketoglutarate dehydrogenase was the major fate of glutamine, flux of glutamine to lipid via reductive carboxylation of -ketoglutarate was demonstrated by measuring incorporation of [5-14C]glutamine into14C-lipid. In media containing glucose (6 mM), and glutamine (0.75 mM) 47 per cent of the lipid synthesized from substrates in the media was derived from glutamine via reductive carboxylation and 49 per cent from glucose. These findings of nearly equal fluxes suggest that lipogenesis via reductive carboxylation may be an important role of glutamine in hepatoma cells.  相似文献   
68.
 The analogy between H-bonded nucleobase pairs and their metalated analogues is extended to the hemiprotonated pair of 7,9-dimethylguanine (7,9-DimeG) and the Watson-Crick and reversed Watson-Crick pair between 7,9-dimethylguaninium (7,9-DimeGH+) and 1-methylcytosine (1-MeC). The crystal structure analyses of two model compounds, trans–[Pt(CH3NH2)2(7,9-DimeG-N1)2](NO3)2 (1) and trans–[Pt(NH3)2(1-MeC-N3)(7, 9-DimeG-N1)](PF6)2· 2.5 H2O (3a) are reported. Pt binding is through N1 of 7,9-DimeG and N3 of 1-MeC. In solution, 3a exists in a mixture with Watson-Crick and reversed Watson-Crick arrangements of the two bases, depending on solvent, concentration and anions. Received: 16 October 1996 / Accepted: 27 January 1997  相似文献   
69.
An evaluation of ‘rapid review’ as a method of quality control of cervical smears using the AxioHOME miscroscope One method of quality control which has recently been recommended by professional bodies in the UK is the ‘rapid review’ method. This involves the microscopic 30 s review of all negative cervical smears with the intention of flagging potential missed abnormalities. Although it has been suggested that rapid review is better than 10% random rescreening of negative smears, the efficiency and efficacy of this method of quality control have not been thoroughly evaluated. We have used the AxioHOME system, which can record the area of a slide covered and the screening time, to investigate slide coverage during rapid review quality control, as performed by 15 cytoscreeners and MLSOs reviewing a test set of 22 slides each. The test set comprised 18 negative slides, three positive slides, and one unsatisfactory slide. We have recorded two distinct methods of rapid review in use amongst cytotechnologists, the step method and the whole slide method. The data show that rapid review takes longer on average than the recommended 30 s, the mean screening times being 76 s and 82 s for the step and whole slide methods, respectively. Abnormal smears were missed on three of 15 occasions by the step method (sensitivity 80%, positive predictive value 85%), and on seven of 30 occasions by the whole slide method (sensitivity 76.6%, positive predictive value 45%). However, the 95% confidence intervals were wide (57.7–90.7% for the step method, and 51.9–95.7% for the whole slide method). Analysis of scanning tracks and screening rates shows significant flaws in the methodology of rapid review. Abnormal cells were not identified, although dyskaryotic cells were included in the scanning track on nine occasions, seven using the whole slide method and two using the step method. On one occasion (using the step method) abnormal cells were not identified because they were not included in the scanning track. Further research is in progress to determine optimal methods of rapid review, and whether the rapid review technique is as effective as automated screening systems for quality assurance in cytology. Evaluation de la technique de ‘Relecture Rapide’ comme méthode de contrôle de qualité des frottis cervico-utérins, à l'aide du microscope AxioHOME Une des méthodes de contrôle de qualité récemment recommandée par le corps professionnel du Royaume Uni est la méthode dite de ‘relecture rapide’. Cette méthode consiste en une deuxième lecture d'une durée de trente secondes de tous les frottis cervicaux négatifs et dont l'objectif est de détecter les anomalies ayant pu échapper au premier examen. Bien qu'il ait été suggéré que cette méthode de relecture rapide soit meilleure que la relecture de 10% des frottis négatifs tirés au sort, le rendement et l'efficacité de cette méthode de contrôle de qualité n'ont pas été évalués complètement. Nous avons utilisé le système AxioHOME capable d'enregistrer la plage de la lame qui a été explorée ainsi que le temps de lecture afin d'étudier la surface explorée au cours de cette relecture rapide telle qu'elle a pu être pratiquée par quinze cytotechniciens et MLSOs, chacun ayant relu une série test de vingt deux lames. Cette série test comprenait dix huit lames négatives, trois lames positives et un frottis non satisfaisant. Nous avons noté que les cytotechniciens utilisaient deux méthodes de relecture rapide différentes, la méthode ‘pas à pas’ et la méthode ‘globale’. Les données montrent que la relecture rapide prend, en moyenne, un temps supérieur aux trente secondes recommandées, la moyenne des temps de lecture étant de 76 secondes et de 82 secondes respectivement pour la méthode ‘pas à pas’ et la méthode ‘globale’. Les anomalies n'ont pas été détectées dans trois cas sur quinze par la méthode ‘pas à pas’ (sensibilité 80%, valeur prédictive positive 85%), et dans 7 cas sur 30 par la méthode globale (sensibilité 76,6%, valeur prédictive positive 45%). Toutefois, l'intervalle de confiance à 95% est important (57,7%-90,7% pour la méthode ‘pas à pas’ et 51,9%-95,7% pour la méthode globale). L'analyse des surfaces balayées et des taux de détection montre des points faibles significatifs de cette méthodologie de relecture rapide. Dans 9 cas, les anomalies n'ont pas été identifiées alors que des cellules dyskaryotiques étaient présentes dans les plages balayées au cours de la relecture (sept utilisant la méthode globale et deux utilisant la méthode ‘pas à pas’). Dans un cas (avec la méthode ‘pas à pas’) les cellules anormales n'ont pas été identifiées parce qu'elles étaient absentes des plages de relecture. Des études sont en cours afin de déterminer quelles sont les méthodes optimales de relecture rapide et si ces techniques de relecture rapide sont aussi efficaces que les systèmes de lecture automatisée pour l'assurance de qualité en cytologie cervico-utérine. ‘Rapid Review’ als Methode der Qualitätskontrolle gynäkologischer Abstriche, Überprüfung mit dem AxioHOME-Mikroskop Die empfohlene ‘Rapid Review’ Kontrolle aller negativen Abstriche in nur 30 Sekunden anstelle des Nachscreenens von 10% der Präparate ist in ihrer Zuverlässigkeit bislang nicht überprüft worden. Mit Hilfe des AxioHOME-Mikroskops ist es möglich sowohl die ausgewertete Fläche, als auch die erforderliche Zeit zu erfassen. 15 Auswerter prüften mit der Methode jeweils einen Testsatz von 22 Präparaten. Er enhielt 18 negative, 3 positive und 1 nichtauswertbaren Abstrich. Getestet wurden zwei verschiedene Vorgehensweisen: die schrittweise und die das ganze Präparat erfassende. Beide erfordern mehr Zeit als 30 Sekunden; der mittlere Zeitaufwand betrug für die Schrittmethode 76 und für die Ganzheitsmethode 82 Sekunden. Die Schrittmethode verfehlte 3/15 Anomalien (Sensitivität 80%, positiver prädiktiver Wert 85%), die Ganzheitsmethode 7/30 (Sensitivität 76,6%, positiver prädiktiver Wert 45%). Der 95% Konfi denzbereich reichte für die Schrittmethode von 57,5–90,7% und für die Ganzheitsmethode von 51,9–95,7%). Die Analyse deckt wesentliche Schwachstellen des Rapid Review-Verfahrens auf. In 9 Fällen lagen nicht erkannte Zellatypien in den kontroll ierten Bahnen (7 bei des Schrittmethode, 2 bei der Ganzheitsmethode). Einmal lagen sie bei der Schrittmethode ausserhalb der geprüften Bahnen. Weitere Studien werden prüfen ab das Rapid Review-Verfahren automatisierten Systemen vergleichbar ist.  相似文献   
70.
Analysis of clonality in cytologic material using the polymerase chain reaction (PCR) Immunoglobulin heavy chain (IgH) gene rearrangement analysis was performed on 27 fine needle aspiration (FNA) specimens (13 reactive hyperplasia, 11 B cell non-Hodgkin's lymphoma (B-NHL), one Hodgkin's disease and two suspicious of non-Hodgkin's lymphoma). Satisfactory amplification was achieved in 23/27 cases. A polyclonal pattern was seen in 14 cases (11 reactive hyperplasia, one B-NHL, one suspicious of lymphoma, one Hodgkin's disease). A monoclonal band was seen in nine cases (eight B-NHL, one reactive hyperplasia). Amplification was unsuccessful in four cases. Clonal analysis by PCR-based IgH gene rearrangement analysis can be successfully applied to FNA material and can be useful in diagnosis, but the results must be interpreted in conjunction with morphology and other ancillary information. Analyse de la clonalité en utilisant la PCR sur matériel cytologique L'analyse des réarrangements géniques des chaînes lourdes des immunoglobulines (IgH) a été réalisée sur 27 produits de ponction à l'aiguille fine (13 cas d'hyperplasie réactionnelle, 11 cas de lymphome non hodgkinien de type B (LNH-B), un cas de maladie de Hodgkin et deux cas suspects de lymphome malin non hodgkinien. Une amplification satisfaisante a été obtenue dans 23 cas sur 27. Un aspect polychonal a été observé dans 14 cas (11 hyperplasies réactionnelles, 1 lymphome malin non hodgkinien de type B, 1 cas suspect de lymphome, 1 cas de maladie de Hodgkin). Une bande monoclonale a été observée dans 9 cas (8 LNH-B, 1 hyperplasie réactionnelle). L'amplification n'a pas réussi dans quatre cas. L'analyse de la clonalité par analyse des réarrangements géniques par PCR peut être appliquée avec succès au matériel cytologique qui est obtenu par ponction à l'aiguille fine et elle peut être utile au plan diagnostique, mais les résultats doivent étre interprétés en intégrant les informations morphologiques et les autres données complémentaires. Polymerase Chain Reaction an zytologischem Material Die Analyse schwerer Immunglobulinketten (IgH) wurde an 27 FNP (13 reaktive Hyperplasien, 11 B-NHL, 1 Hodgkin und und zwie verdächtige Fälle) analysiert. Eine ausreichende Amplifikation wurde in 23/27 Fällen erzielt. Ein polyklonales Muster wurde in 14 Fällen beobachtet (11 reaktive Hyperplasien, 1 B-NHL, 1 Hodgkin sowie 1 verdächtiger Fall). Ein monoklonales Band wurde 9 mal gefunden (8 B-NHL, 1 reaktive Hyperplasie). Die Amplifikation war ungenügend in 4 Fällen. Die PCR-Analyse kann für die Diagnostik von Nutzen sein muss jedoch zusammen mit der Morphologie und anderen Informationen interpretiert werden.  相似文献   
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