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91.
Prostanoids modulate the activity of human pregnant myometrium and their functional role can be appreciated through characterisation of prostanoid receptors and tissue concentration of prostanoids. We have applied a lipidomic approach to elucidate the profile of prostanoids in human non-labouring and labouring myometrium. We have identified a total of nineteen prostanoids including prostacyclin, thromboxanes, prostaglandins and dihydro-prostaglandins. Prostacyclin was the predominant prostanoid in both non-labouring and labouring myometria, with PGD2 and PGF2α being the second most abundant. Although the total amount of prostanoids was increased in the labouring tissue, PGE2 and 13,14-dihydro-15-keto-PGE2 were the only prostanoids to increase significantly at early and late labour (p≤0.001). Our data suggest that PGF2α plays an important role in parturition, whilst the increase in PGE2 could occur to facilitate cervical dilation and relaxation of the lower myometrium during labour. Although the elevation in TXA2 was less marked than expected, in terms of translation to function even a relatively small increase in the level of this potent spasmogen may have significant effects.  相似文献   
92.
Pustjens  T. F. S.  Streukens  B.  Vainer  J.  Gho  B.  Ruiters  A. W.  Stein  M.  Ilhan  M.  Veenstra  L.  Theunissen  R.  Bekkers  S. C. A. M.  van’t Hof  A. W. J.  Rasoul  S. 《Netherlands heart journal》2020,28(2):75-80
Netherlands Heart Journal - To compare ischaemia-driven complete coronary revascularisation by percutaneous coronary intervention (PCI) with usual care in patients with non-ST-elevation myocardial...  相似文献   
93.
The antisense oligonucleotide Nusinersen has been recently licensed to treat spinal muscular atrophy (SMA). Since SMA type 3 is characterized by variable phenotype and milder progression, biomarkers of early treatment response are urgently needed. We investigated the cerebrospinal fluid (CSF) concentration of neurofilaments in SMA type 3 patients treated with Nusinersen as a potential biomarker of treatment efficacy. The concentration of phosphorylated neurofilaments heavy chain (pNfH) and light chain (NfL) in the CSF of SMA type 3 patients was evaluated before and after six months since the first Nusinersen administration, performed with commercially available enzyme-linked immunosorbent assay (ELISA) kits. Clinical evaluation of SMA patients was performed with standardized motor function scales. Baseline neurofilament levels in patients were comparable to controls, but significantly decreased after six months of treatment, while motor functions were only marginally ameliorated. No significant correlation was observed between the change in motor functions and that of neurofilaments over time. The reduction of neurofilament levels suggests a possible early biochemical effect of treatment on axonal degeneration, which may precede changes in motor performance. Our study mandates further investigations to assess neurofilaments as a marker of treatment response.  相似文献   
94.
Primary biliary cholangitis (PBC) is an autoimmune disease characterized by chronic destruction of the bile ducts. A major unanswered question regarding the pathogenesis of PBC is the precise mechanisms of small bile duct injury. Emperipolesis is one of cell‐in‐cell structures that is a potential histological hallmark associated with chronic hepatitis B. This study aimed to clarify the pathogenesis and characteristics of emperipolesis in PBC liver injury. Sixty‐six PBC patients, diagnosed by liver biopsy combined with laboratory test, were divided into early‐stage PBC (stages I and II, n = 39) and late‐stage PBC (stages III and IV, n = 27). Emperipolesis was measured in liver sections stained with haematoxylin‐eosin. The expressions of CK19, CD3, CD4, CD8, CD20, Ki67 and apoptosis of BECs were evaluated by immunohistochemistry or immunofluorescence double labelling. Emperipolesis was observed in 62.1% of patients with PBC, and BECs were predominantly host cells. The number of infiltrating CD3+ and CD8+ T cells correlated with the advancement of emperipolesis (R2 = 0.318, P < .001; R2 = 0.060, P < .05). The cell numbers of TUNEL‐positive BECs and double staining for CK19 and Ki67 showed a significant positive correlation with emperipolesis degree (R2 = 0.236, P < .001; R2 = 0.267, P < .001). We conclude that emperipolesis mediated by CD8+ T cells appears to be relevant to apoptosis of BEC and thus may aggravate the further injury of interlobular bile ducts.  相似文献   
95.
96.
A multidisciplinary approach was carried out in order to study the biodeterioration and the associated microbiome of a XVIII Century wax seal coloured with minium. A small wax seal fragment was observed by scanning electron microscopy combined with energy dispersive spectroscopy in non-destructive mode. The same object was analysed by Raman and Fourier-transform infrared spectroscopy. The identification of the microbiota growing on the seal was performed with both a culture-dependent strategy, combined with hydrolytic assays, and high-throughput sequencing using the MinION platform. The whole bacterial 16S rRNA gene and the fungal markers ITS and 28S rRNA were targeted. It was observed that the carnauba wax coloured with lead tetroxide (minium) was covered by a biofilm consisting of a network of filaments and other structures of microbial origin. The culture-dependent and culture-independent investigations showed the presence of a complex microbiota composed mainly by fungal members, which demonstrated interesting properties related to lipids and lead processing. The formation of lead soaps and secondary biogenic minerals was also described.  相似文献   
97.
Plasma Physics Reports - A subthreshold discharge excited by a microwave beam in air at pressures close to atmospheric is studied as a plasmachemical method of nitrogen oxide (NOx) production. It...  相似文献   
98.
99.
ABSTRACT

A novel compound, (R)-4-ethoxy-2-hydroxy-4-oxobutanoic acid (1), and six known compounds (27) were isolated from the fruiting bodies of the wild edible mushroom Leucopaxillus giganteus. The planar structure of 1 was determined by the interpretation of spectroscopic data analysis. The absolute configuration of 1 was determined by comparing specific rotation of the synthetic compounds. In the plant regulatory assay, the isolated compounds (17) and the chemically prepared compounds (810) were evaluated their biological activity against the lettuce (Lactuca sativa) growth. Compounds 1 and 310 showed the significant regulatory activity of lettuce growth. 1 showed the strongest inhibition activity among the all the compounds tested. In the lung cancer assay, all the compounds were assessed the mRNA expression of Axl and immune checkpoints (PD-L1, PD-L2) in the human A549 alveolar epithelial cell line by RT-PCR. Compounds 110 showed significant inhibition activity against Axl and/or immune checkpoint.  相似文献   
100.
Si ran Wang  Jia Yan  Bu er Ha  Yu’e Bai 《Phyton》2021,90(2):595-604
Hydrangea bretschneideri Dipp is a highly popular ornamental plant for garden decoration. Genetic engineering technology has been successfully used in many plant species, but it is limited in Hydrangea. Here we established an efficient regeneration system by using stem segments as explants for the first time. In our study, the plant growth regulators (PGRs) were evaluated at the different regeneration processes, including axillary shoots regeneration and root induction. We found that the optimal concentration for axillary buds’ induction was 2.0 mgL−1 6-BA and 0.5 mgL−1 1 IAA, its highest induction rate was 70%. Moreover, the highest axillary shoots proliferation coefficient was 10.7 on the Murashige and Skoog (MS) medium with 2.0 mgL−1 6-benzyladenine (BA), 0.2 mgL−1 indole-3-butyric acid (IBA), and 1.0 mgL−1 gibberellin A3 (GA3). The highest frequency of root induction was 80.0 ± 0.06% by culturing the elongated shoots in 1/2 MS medium containing 0.1 mgL−1 IBA. In summary, our study will provide an effective technology for large-scale propagation and important pathway for promoting the popularization and application of Hydrangea bretschneideri Dipp.  相似文献   
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