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71.
IL-35 subunit EBI3 is up-regulated in pulmonary fibrosis tissues. In this study, we investigated the pathological role of EBI3 in pulmonary fibrosis and dissected the underlying molecular mechanism. Bleomycin-induced pulmonary fibrosis mouse model was established, and samples were performed gene expression analyses through RNAseq, qRT-PCR and Western blot. Wild type and EBI3 knockout mice were exposed to bleomycin to investigate the pathological role of IL-35, via lung function and gene expression analyses. Primary lung epithelial cells were used to dissect the regulatory mechanism of EBI3 on STAT1/STAT4 and STAT3. IL-35 was elevated in both human and mouse with pulmonary fibrosis. EBI3 knockdown aggravated the symptoms of pulmonary fibrosis in mice. EBI3 deficiency enhanced the expressions of fibrotic and extracellular matrix-associated genes. Mechanistically, IL-35 activated STAT1 and STAT4, which in turn suppressed DNA enrichment of STAT3 and inhibited the fibrosis process. IL-35 might be one of the potential therapeutic targets for bleomycin-induced pulmonary fibrosis.  相似文献   
72.
An all solid state potentiometric immunosensor (ASPI) has been developed to study the activation process of neuronal nitric oxide synthase (nNOS), the enzyme involved in the synthesis of nitric oxide generated under physiological conditions. At first, an all solid state H+-selective ISE was fabricated with the carboxylated poly(vinyl chloride) (PVC-COOH) film containing H+ ionophore, antibody was then immobilized on the polymer layer. The immunocomplex formation was detected by monitoring pH change due to interaction between urease labeled secondary antibody and antigen. Experimental parameters such as the amount of phosphorylated nNOS immobilized on the electrode surface and pH responses due to the antibody–antigen reaction were studied in detail. The calibration plot of the potentiometric potential vs. phosphorylated nNOS concentration exhibited a linear relationship in the range of 3.4–340.0 μg/ml. The calibration sensitivity of the phosphorylated nNOS immunosensor was −0.073 ± 0.002 mV/μg ml−1. The detection limit of nNOS was determined to be 0.2 μg/ml based on five-time measurements (95% confidence level, k = 3, n = 5). The reliability of the immunosensor was examined with rat brain tissues as well as neuronal cells, and the results shown were good, implying a promising approach for a novel electrochemical immunosensor platform with potential applications to clinical diagnosis.  相似文献   
73.
Four 5'-substituted fluoro-neplanocin A analogues la-d were designed and synthesized, and the inhibitory activity against SAH was in the following order: NH2 > SH > F, N3, indicating a hydrogen bonding donor is essential for inhibitory activity.  相似文献   
74.

Background

GPi (Internal globus pallidus) DBS (deep brain stimulation) is recognized as a safe, reliable, reversible and adjustable treatment in patients with medically refractory dystonia.

Objectives

This report describes the long-term clinical outcome of 36 patients implanted with GPi DBS at the Neurosurgery Department of Seoul National University Hospital.

Methods

Nine patients with a known genetic cause, 12 patients with acquired dystonia, and 15 patients with isolated dystonia without a known genetic cause were included. When categorized by phenomenology, 29 patients had generalized, 5 patients had segmental, and 2 patients had multifocal dystonia. Patients were assessed preoperatively and at defined follow-up examinations postoperatively, using the Burke-Fahn-Marsden dystonia rating scale (BFMDRS) for movement and functional disability assessment. The mean follow-up duration was 47 months (range, 12–84)

Results

The mean movement scores significantly decreased from 44.88 points preoperatively to 26.45 points at 60-month follow up (N = 19, P = 0.006). The mean disability score was also decreased over time, from 11.54 points preoperatively to 8.26 points at 60-month follow up, despite no statistical significance (N = 19, P = 0.073). When analyzed the movement and disability improvement rates at 12-month follow up point, no significant difference was noted according to etiology, disease duration, age at surgery, age of onset, and phenomenology. However, the patients with DYT-1 dystonia and isolated dystonia without a known genetic cause showed marked improvement.

Conclusions

GPi DBS is a safe and efficient therapeutic method for treatment of dystonia patients to improve both movement and disability. However, this study has some limitations caused by the retrospective design with small sample size in a single-center.  相似文献   
75.
Mammalian secretory phospholipases A(2) (sPLA(2)) have been implicated in cellular eicosanoid biosynthesis but the mechanism of their cellular action remains unknown. To elucidate the spatiotemporal dynamics of sPLA(2) mobilization and determine the site of its lipolytic action, we performed time-lapse confocal microscopic imaging of fluorescently labeled sPLA(2) acting on human embryonic kidney (HEK) 293 cells the membranes of which are labeled with a fluorogenic phospholipid, N-((6-(2,4-dinitrophenyl)amino)hexanoyl)-1-hexadecanoyl-2-(4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-pentanoyl)-sn-glycero-3-phosphoethanolamine. The Western blotting analysis of HEK293 cells treated with exogenous sPLA(2)s showed that not only the affinity for heparan sulfate proteoglycan but also other factors, such as sPLA(2) hydrolysis products or cytokines, are necessary for the internalization of sPLA(2) into HEK293 cells. Live cell imaging showed that the hydrolysis of fluorogenic phospholipids incorporated into HEK293 cell membranes was synchronized with the spatiotemporal dynamics of sPLA(2) internalization, detectable initially at the plasma membrane and then at the perinuclear region. Also, immunocytostaining showed that human group V sPLA(2) induced the translocation of 5-lipoxygenase to the nuclear envelope at which they were co-localized. Together, these studies provide the first experimental evidence that the internalized sPLA(2) acts on the nuclear envelope to provide arachidonate for other enzymes involved in the eicosanoid biosynthesis.  相似文献   
76.
Paek  Hyo-Jin  Luo  Zhao-Bo  Choe  Hak-Myong  Quan  Biao-Hu  Gao  Kai  Han  Sheng-Zhong  Li  Zhou-Yan  Kang  Jin-Dan  Yin  Xi-Jun 《Transgenic research》2021,30(5):663-674
Transgenic Research - Herein, we investigate the high incidence of umbilical hernia and tippy-toe standing and their underlying changes in gene expression and proliferation in myostatin knockout...  相似文献   
77.
Abs of the IgG isotype are efficiently transported from mother to neonate and have an extended serum t(1/2) compared with Abs of other isotypes. Circumstantial evidence suggests that the MHC class I-related protein, the neonatal FcR (FcRn), is the FcR responsible for both in vivo functions. To understand the phenotypes imposed by FcRn, we produced and analyzed mice with a defective FcRn gene. The results provide direct evidence that perinatal IgG transport and protection of IgG from catabolism are mediated by FcRn, and that the latter function is key to IgG homeostasis, essential for generating a potent IgG response to foreign Ags, and the basis of enhanced efficacy of Fc-IgG-based therapeutics. FcRn is therefore a promising therapeutic target for enhancing protective humoral immunity, treating autoimmune disease, and improving drug efficacy.  相似文献   
78.

Background

Pharmacoresistance is a major issue in the treatment of epilepsy. However, the mechanism underlying pharmacoresistance to antiepileptic drugs (AEDs) is still unclear, and few animal models have been established for studying drug resistant epilepsy (DRE). In our study, spontaneous recurrent seizures (SRSs) were investigated by video-EEG monitoring during the entire procedure.

Methods/Principal Findings

In the mouse pilocarpine-induced epilepsy model, we administered levetiracetam (LEV) and valproate (VPA) in sequence. AED-responsive and AED-resistant mice were naturally selected after 7-day treatment of LEV and VPA. Behavioral tests (open field, object exploration, elevated plus maze, and light-dark transition test) and a microRNA microarray test were performed. Among the 37 epileptic mice with SRS, 23 showed significantly fewer SRSs during administration of LEV (n = 16, LEV sensitive (LS) group) or VPA (n = 7, LEV resistant/VPA sensitive (LRVS) group), while 7 epileptic mice did not show any amelioration with either of the AEDs (n = 7, multidrug resistant (MDR) group). On the behavioral assessment, MDR mice displayed distinctive behaviors in the object exploration and elevated plus maze tests, which were not observed in the LS group. Expression of miRNA was altered in LS and MDR groups, and we identified 4 miRNAs (miR-206, miR-374, miR-468, and miR-142-5p), which were differently modulated in the MDR group versus both control and LS groups.

Conclusion

This is the first study to identify a pharmacoresistant subgroup, resistant to 2 AEDs, in the pilocarpine-induced epilepsy model. We hypothesize that modulation of the identified miRNAs may play a key role in developing pharmacoresistance and behavioral alterations in the MDR group.  相似文献   
79.
Ca(2+)-saturated calmodulin (CaM) directly associates with and activates CaM-dependent protein kinase I (CaMKI) through interactions with a short sequence in its regulatory domain. Using heteronuclear NMR (13)C-(15)N-(1)H correlation experiments, the backbone assignments were determined for CaM bound to a peptide (CaMKIp) corresponding to the CaM-binding sequence of CaMKI. A comparison of chemical shifts for free CaM with those of the CaM.CaMKIp complex indicate large differences throughout the CaM sequence. Using NMR techniques optimized for large proteins, backbone resonance assignments were also determined for CaM bound to the intact CaMKI enzyme. NMR spectra of CaM bound to either the CaMKI enzyme or peptide are virtually identical, indicating that calmodulin is structurally indistinguishable when complexed to the intact kinase or the peptide CaM-binding domain. Chemical shifts of CaM bound to a peptide (smMLCKp) corresponding to the calmodulin-binding domain of smooth muscle myosin light chain kinase are also compared with the CaM.CaMKI complexes. Chemical shifts can differentiate one complex from another, as well as bound versus free states of CaM. In this context, the observed similarity between CaM.CaMKI enzyme and peptide complexes is striking, indicating that the peptide is an excellent mimetic for interaction of calmodulin with the CaMKI enzyme.  相似文献   
80.
Muscidae are a dipteran family which is important for forensic investigations. However, it has received limited attention in forensic entomological experiments as a reason of identification issues. It is hard to identify specimens by morphological methods, especially in developmental stages. Therefore, complete mitochondrial genome sequences can be important tool in forensic entomology for identifying species. In this study we sequenced and analyzed the first complete mitochondrial genome from a forensically important Muscidae species Hydrotaea (=Ophyra) chalcogaster by next-generation sequencing. The mitochondrial genome of the sequenced species is circular molecules of 17,076?bp which have the typical mitochondrial genome complement of 13 protein-coding genes, 22 tRNAs, two ribosomal RNA genes and a control region. Rearrangements of gene positions are identical with the ancestral insect genome. Furthermore, phylogenetic relationships of the family Muscidae were evaluated in regard to mitochondrial protein coding genes. The inferred trees indicate that the Muscidae is a paraphyletic family. These data provide additional information for molecular identification of muscid species.  相似文献   
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