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121.
Romero R Espinoza J Hassan S Gotsch F Kusanovic JP Avila C Erez O Edwin S Schmidt AM 《Journal of perinatal medicine》2008,36(5):388-398
Abstract Objective: The receptor for advanced glycation end products (RAGE) has been proposed to participate in the innate and adaptive immune responses. RAGE can induce production of pro-inflammatory cytokines and chemokines, as well as neutrophil chemotaxis in a manner that may be suppressed or stimulated by soluble, truncated forms of RAGE including the soluble form of RAGE (sRAGE) and endogenous secretory RAGE (esRAGE). The objective of this study was to determine whether intra-amniotic infection/inflammation (IAI) is associated with changes in the amniotic fluid concentration of sRAGE and esRAGE. Study design: Amniotic fluid (AF) was retrieved from patients in the following groups: 1) mid-trimester (14-18 weeks of gestation; n=68); 2) term not in labor (n=24); 3) term in labor (n=51); 4) preterm labor and intact membranes (n=124); and 5) preterm PROM (n=80). Intra-amniotic infection and inflammation were defined as the presence of a positive amniotic fluid culture for microorganisms and an AF interleukin-6 concentration >/=2.6 ng/mL, respectively. The AF concentration of sRAGE and esRAGE were determined using specific and sensitive ELISAs which measured total immunoreactive sRAGE and esRAGE, respectively. Patients were matched for gestational age at amniocentesis to compare the AF concentration of sRAGE and esRAGE in patients with and without IAI. Non-parametric statistics were used for analysis and a P<0.05 was considered significant. Results: 1) Patients at term not in labor had higher median AF concentrations of sRAGE and esRAGE than those in the mid-trimester (P<0.001 for both comparisons) and those at term in labor (P=0.03 and P=0.04, respectively); 2) patients with preterm labor and intact membranes with intra-amniotic infection/inflammation (IAI) had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.02 and P=0.005, respectively); 3) similarly, patients with preterm PROM with IAI had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.03 and P=0.02, respectively). Conclusion: Intra-amniotic infection/inflammation is associated with increased amniotic fluid concentrations of sRAGE and esRAGE. Changes in the amniotic fluid concentration of sRAGE and esRAGE may represent part of the immune response to intra-amniotic infection/inflammation. 相似文献
122.
123.
Mazaki-Tovi S Romero R Kusanovic JP Erez O Pineles BL Gotsch F Mittal P Than NG Espinoza J Hassan SS 《Seminars in perinatology》2007,31(3):142-158
Recurrent preterm birth is frequently defined as two or more deliveries before 37 completed weeks of gestation. The recurrence rate varies as a function of the antecedent for preterm birth: spontaneous versus indicated. Spontaneous preterm birth is the result of either preterm labor with intact membranes or preterm prelabor rupture of the membranes. This article reviews the body of literature describing the risk of recurrence of spontaneous and indicated preterm birth. Also discussed are the factors which modify the risk for recurrent spontaneous preterm birth (a short sonographic cervical length and a positive cervicovaginal fetal fibronectin test). Patients with a history of an indicated preterm birth are at risk not only for recurrence of this subtype, but also for spontaneous preterm birth. Individuals of black origin have a higher rate of recurrent preterm birth. 相似文献
124.
Plasma adiponectin concentrations in non-pregnant, normal and overweight pregnant women 总被引:1,自引:0,他引:1
Nien JK Mazaki-Tovi S Romero R Erez O Kusanovic JP Gotsch F Pineles BL Gomez R Edwin S Mazor M Espinoza J Yoon BH Hassan SS 《Journal of perinatal medicine》2007,35(6):522-531
AIMS: Adiponectin is an adipokine that has anti-diabetic, anti-atherogenic, anti-inflammatory and angiogenic properties. This hormone has been implicated in both the physiological adaptation to normal pregnancy and in obstetrical complications. The aims of this study were to determine normal maternal plasma concentrations of adiponectin throughout gestation and to explore the relationships between plasma adiponectin concentration, pregnancy, and maternal overweight. METHODS: A cross-sectional study was designed to include normal pregnant (normal weight and overweight; 11-42 weeks of gestation), and non-pregnant women. Plasma adiponectin concentration was determined by immunoassay. Non-parametric statistics were used for analysis. RESULTS: (1) Adiponectin was detectable in the plasma of all patients; (2) there was no significant differences in the median adiponectin concentration between pregnant and non-pregnant women; (3) plasma adiponectin concentrations were negatively correlated with gestational age only among normal weight pregnant women; and (4) overweight patients had significantly lower plasma adiponectin concentrations than normal weight women. CONCLUSIONS: Consistent with the increased insulin resistance and weight gain that occur in pregnancy, adiponectin concentrations were negatively correlated with gestational age. The results of this study and the nomogram herein presented, can serve as the basis to explore the relationship between adiponectin and pregnancy complications and facilitate the clinical use of this important adipokine. 相似文献
125.
126.
Diabetes in pregnancy: a review of current evidence 总被引:2,自引:0,他引:2
PURPOSE OF REVIEW: There is controversy about the best approach to screening and management for gestational diabetes. In the recent Confidential Enquiry in Maternal and Child Health (CEMACH) the outcome of women with diabetes compared with women without diabetes. The results were exceptionally poor, suggesting the need for a new management approach. The aim of this review is to address these findings and our suggested care pathways. RECENT FINDINGS: The CEMACH report showed the congenital malformation rate was four to 10-fold higher, the perinatal mortality rate was four to seven-fold higher, stillbirth was five times more common, and babies were three times more likely to die in the first 3 months of life. Only 39% of women with established diabetes took folic acid and only 37% had some documentation of glycaemic control before pregnancy. Overall, less than a fifth of NHS trusts in the UK had any kind of multidisciplinary preconception services. The results for women with type 2 diabetes were as bad as those for type 1. Caesarean delivery rates were very high (67%). SUMMARY: Prepregnancy counselling and multidisciplinary team management is the key in achieving good pregnancy outcomes. There is emerging evidence about the safety and efficacy of oral hypoglycaemics like metformin in pregnancy. 相似文献
127.
目的:研究槟榔子(Areca catechu)粗提取物中所含的抗血小板聚集及抑制乙酰胆碱酯酶活性的有效成分及其作用机制。方法:使用70%甲醇水溶液对槟榔子进行粗提取。使用生物发光血小板凝集仪在富血小板血浆中测定槟榔子粗提取物的抗血小板聚集作用,使用分光光度计在试管内测定槟榔子粗提取物对乙酰胆碱酯酶活性的抑制作用。检测槟榔子中的多种化合物以测定槟榔子中抗血小板聚集及抑制乙酰胆碱酯酶活性的有效成分。结果:槟榔子粗提取物能够抑制花生四烯酸、二磷酸腺苷、血小板活化因子、肾上腺素及钙离子载体引起的血小板聚集,尤其对二磷酸腺苷及钙离子载体引起的血小板聚集的抑制最为明显;槟榔子粗提取物能够显著抑制乙酰胆碱酯酶的活性。在所检测的槟榔子所含化合物中,只有儿茶素对肾上腺素引起的血小板聚集有显著的抑制作用,而这种抑制作用显著弱于槟榔子粗提取物,提示槟榔子中的其他成分参与了这种抑制作用;鞣酸、没食子酸、薯蓣皂苷元和异去甲槟榔次碱能够抑制乙酰胆碱酯酶的活性,其中鞣酸的抑制作用强于槟榔子粗提取物。结论:槟榔子中含有抗血小板聚集及抑制乙酰胆碱酯酶活性的有效成分,而发挥这些功效的确切成分有待进一步的研究证实。 相似文献
128.
Nicole Fakhoury Sayegh Gessica N. H. A. Heraoui Hassan Younes Lea Nicole Sayegh Christa Boulos Raymond Sayegh 《Nutrients》2022,14(12)
Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver injury worldwide. NAFLD can evolve into non-alcoholic steatohepatitis (NASH) with or without fibrosis. The objectives of this study were to determine the nutritional profile and dietary patterns of NAFLD Lebanese patients and to report the type of diet-related to the presence of hepatic fibrosis. We hypothesized that the traditional pattern was related to a low risk of fibrosis. This cross-sectional study included 320 eligible Lebanese NAFLD patients. Three dietary patterns were identified: the Traditional diet, the High Fruit diet, and the Westernized diet. Multivariate analysis showed a significant relationship between high adherence to the traditional diet and absence of hepatic fibrosis with a decreased risk of 82%, p = 0.031 after adjusting for its covariables. Fruits were absent from this dietary pattern. Although our results pointed to a possible relationship between fibrosis in NAFLD patients and fruit intake, experimental studies are needed to show whether this is a causal relationship. However, the results obtained in this study may contribute to the planning of dietary interventions and recommendations and enable a better follow-up for NAFLD patients with fibrosis. 相似文献
129.
Sehrish Bilal Muhammad Nasir M. Mudassir Hassan Muhammad Fayyaz ur Rehman Amtul Jamil Sami Akhtar Hayat 《RSC advances》2022,12(26):16860
Herein, an electrochemical biosensor has been prepared to assess the sensitivity of an organophosphate insecticide, malathion, to acetylcholinesterase (AChE) enzyme of three insects including Apis mellifera (honeybee), Tribolium castaneum (red flour beetle), and Zootermopsis nevadensis (dampwood termite). A composite of nickel chromite (NiCr2O4) and graphitic carbon nitride (g-C3N4) was prepared and characterized for its morphological, chemical and electrical properties. The NiCr2O4/g-C3N4 composite integrated pencil graphite electrodes were used to covalently immobilize insect AChE enzymes and amperometric response of bioelectrodes was determined through cyclic voltammetry. The prepared bioelectrodes exhibited high enzyme immobilization efficiency and electro-catalytic performance. The integrated bioelectrodes could efficiently detect malathion induced inhibition of insects'' AChEs. The linear ranges for malathion were found to be 0.1–1.6 μM, 1–40 nM and 2–100 nM, and LODs were 2 nM, 0.86 nM and 2.3 nM for A. mellifera, T. castaneum, and Z. nevadensis, respectively. Additionally, the biosensing platform developed using A. mellifera AChE was found highly sensitive and effective for malathion recoveries from spiked wheat flour samples with high recovery rates. Moreover, the proposed method was adequately reproducible and selective. The results revealed that A. mellifera AChE is less sensitive to inhibition by malathion as compared to T. castaneum, and Z. nevadensis AChE. The experimental results were validated through computational docking of malathion with insect AChEs and the results were in correspondence to experimental outcomes. The proposed method can be a plausible alternate to conventional analytical methods to assess the pesticide sensitivity and toxicity of various compounds against insect enzymes.An innovative electrochemical assay has been established to determine pesticide sensitivity against acetylcholinesterase and possible toxicity against insects. The analytical efficiency of three common insect AChEs was determined through this method. 相似文献
130.
Azadeh Nasiri Shaya Mokhtari Reza Jahani Bahram Daraie Hassan Yazdanpanah Mehrdad Faizi Farzad Kobarfard 《RSC advances》2022,12(27):17096
Liquid chromatography-tandem mass spectroscopy (LC-MS/MS) is an accurate and specific technique for drug residue analysis in different matrices. The high specificity and sensitivity of the multiple reaction monitoring (MRM) approach for detecting drugs such as aldehydes, which have the potential to change mass during the sample preparation phase, becomes a drawback during the analysis process. In this study, concerns about the intrusion of solvent molecules into spiramycin''s chemical structure as an aldehydic drug as well as the stability of spiramycin in the milk matrix were addressed. Furthermore, the binding sites where the solvent molecules could bind to spiramycin molecules were investigated through nuclear magnetic resonance (NMR) spectroscopy. It was revealed that water, ethanol, and methanol as protic solvents can add to the formyl group of spiramycin molecules during standard solutions preparation while there was no evidence for the addition of acetonitrile and dimethyl sulfoxide (aprotic solvents). In addition, as time passed, the peak area of spiramycin decreased either in the spiked aqueous sample or milk sample while an increase in the peak area of H2O-bound spiramycin was observed. After 96 h, more than 90% of spiramycin was converted to H2O-bound spiramycin. In conclusion, we can propose the use of aprotic solvents for the preparation of spiramycin standard solutions especially when the prepared solutions are not used instantly. Moreover, ion transitions for both spiramycin and its H2O-added form (843.6 m/z to 173.9 m/z and 861.5 m/z to 173.9 m/z, respectively) should be considered for the accurate quantification of spiramycin residue in aqueous samples such as milk.Water, ethanol, and methanol as protic solvents can add to the formyl group of spiramycin molecules during standard solutions preparation while there was no evidence for the addition of acetonitrile and dimethyl sulfoxide as aprotic solvents. 相似文献