4,621 research outputs found
Modulation of epithelial sodium channel in human alveolar epithelial cells by lipoxin A4 through AhR-cAMP-dependent pathway
Purpose: To investigate the effect of lipoxin A4 (LXA4) on the expressions of protein and mRNA of alveolar epithelial sodium channel (ENaC) in normal and lipopolysaccharide (LPS)-stimulated A549 cells.Methods: A549 cell-lines were randomized into 11 groups (N = 8) and treated. EnaC level was evaluated by Western blot. Total RNA was extracted and reverse-transcribed and then levels of ENaC mRNA, cGMP and cAMP in the cells were determined.Results: LXA4 (10-7mol/L) increased the expressions of α-subunit of ENaC relative to LPS group. In addition, LXA4 significantly up-regulated the expression of mRNAs of α, β and γ subunits of ENaC (p < 0.01). The level of cAMP was increased in LXA4 group, but significantly reduced in LPS group relative to control group (p < 0.05). However, treatment with LXA4 annulled the increased cAMP concentration, compared with LPS group (p < 0.05)Conclusion: These results show that LXA4 influences ENaC up-regulation in normal and LPS stimulated A549 alveolar epithelial cells.Keywords: Acute lung injury, Alveolar epithelial sodium channel, Lipoxin A4, AhR, cAMP, cGM
The Relationship between Brown Adipose Tissue Activity and Neoplastic Status: an 18F-FDG PET/CT Study in the Tropics
<p>Abstract</p> <p>Background</p> <p>Brown adipose tissue (BAT) has thermogenic potential. For its activation, cold exposure is considered a critical factor though other determinants have also been reported. The purpose of this study was to assess the relationship between neoplastic status and BAT activity by 2-deoxy-2-[18F]fluoro-D-glucose (<sup>18</sup>F-FDG) positron emission tomography/computed tomography (PET/CT) in people living in the tropics, where the influence of outdoor temperature was low.</p> <p>Methods</p> <p><sup>18</sup>F-FDG PET/CT scans were reviewed and the total metabolic activity (TMA) of identified activated BAT quantified. The distribution and TMA of activated BAT were compared between patients with and without a cancer history. The neoplastic status of patients was scored according to their cancer history and <sup>18</sup>F-FDG PET/CT findings. We evaluated the relationships between the TMA of BAT and neoplastic status along with other factors: age, body mass index, fasting blood sugar, gender, and outdoor temperature.</p> <p>Results</p> <p>Thirty of 1740 patients had activated BAT. Those with a cancer history had wider BAT distribution (<it>p </it>= 0.043) and a higher TMA (<it>p </it>= 0.028) than those without. A higher neoplastic status score was associated with a higher average TMA. Multivariate analyses showed that neoplastic status was the only factor significantly associated with the TMA of activated BAT (<it>p </it>= 0.016).</p> <p>Conclusions</p> <p>Neoplastic status is a critical determinant of BAT activity in patients living in the tropics. More active neoplastic status was associated with more vigorous TMA of BAT.</p
Protectin DX increases alveolar fluid clearance in rats with 2 lipopolysaccharide-induced acute lung injury
Whole-genome sequencing of cultivated and wild peppers provides insights into Capsicum domestication and specialization
As an economic crop, pepper satisfies people's spicy taste and has medicinal uses worldwide. To gain a better understanding of Capsicum evolution, domestication, and specialization, we present here the genome sequence of the cultivated pepper Zunla-1 (C. annuum L.) and its wild progenitor Chiltepin (C. annuum var. glabriusculum). We estimate that the pepper genome expanded similar to 0.3 Mya (with respect to the genome of other Solanaceae) by a rapid amplification of retrotransposons elements, resulting in a genome comprised of similar to 81% repetitive sequences. Approximately 79% of 3.48-Gb scaffolds containing 34,476 protein-coding genes were anchored to chromosomes by a high-density genetic map. Comparison of cultivated and wild pepper genomes with 20 resequencing accessions revealed molecular footprints of artificial selection, providing us with a list of candidate domestication genes. We also found that dosage compensation effect of tandem duplication genes probably contributed to the pungent diversification in pepper. The Capsicum reference genome provides crucial information for the study of not only the evolution of the pepper genome but also, the Solanaceae family, and it will facilitate the establishment of more effective pepper breeding programs
Benchmarking of eight recurrent neural network variants for breath phase and adventitious sound detection on a self-developed open-access lung sound database-HF_Lung_V1
A reliable, remote, and continuous real-time respiratory sound monitor with
automated respiratory sound analysis ability is urgently required in many
clinical scenarios-such as in monitoring disease progression of coronavirus
disease 2019-to replace conventional auscultation with a handheld stethoscope.
However, a robust computerized respiratory sound analysis algorithm has not yet
been validated in practical applications. In this study, we developed a lung
sound database (HF_Lung_V1) comprising 9,765 audio files of lung sounds
(duration of 15 s each), 34,095 inhalation labels, 18,349 exhalation labels,
13,883 continuous adventitious sound (CAS) labels (comprising 8,457 wheeze
labels, 686 stridor labels, and 4,740 rhonchi labels), and 15,606 discontinuous
adventitious sound labels (all crackles). We conducted benchmark tests for long
short-term memory (LSTM), gated recurrent unit (GRU), bidirectional LSTM
(BiLSTM), bidirectional GRU (BiGRU), convolutional neural network (CNN)-LSTM,
CNN-GRU, CNN-BiLSTM, and CNN-BiGRU models for breath phase detection and
adventitious sound detection. We also conducted a performance comparison
between the LSTM-based and GRU-based models, between unidirectional and
bidirectional models, and between models with and without a CNN. The results
revealed that these models exhibited adequate performance in lung sound
analysis. The GRU-based models outperformed, in terms of F1 scores and areas
under the receiver operating characteristic curves, the LSTM-based models in
most of the defined tasks. Furthermore, all bidirectional models outperformed
their unidirectional counterparts. Finally, the addition of a CNN improved the
accuracy of lung sound analysis, especially in the CAS detection tasks.Comment: 48 pages, 8 figures. To be submitte
Achieving blood pressure control targets in hypertensive patients of rural China - A pilot randomized trial
Background: This study aimed to test the feasibility and titration methods used to achieve specific blood pressure (BP) control targets in hypertensive patients of rural China. Methods: A randomized, controlled, open-label trial was conducted in Rongcheng, China. We enrolled 105 hypertensive participants aged over 60 years, and who had no history of stroke or cardiovascular disease. The patients were randomly assigned to one of three systolic-BP target groups: standard: 140 to \u3c 150 mmHg; moderately intensive: 130 to \u3c 140 mmHg; and intensive: \u3c 130 mmHg. The patients were followed for 6 months. Discussion: The optimal target for systolic blood pressure (SBP) lowering is still uncertain worldwide and such information is critically needed, especially in China. However, in China the rates of awareness, treatment and control are only 46.9%, 40.7%, and 15.3%, respectively. It is challenging to achieve BP control in the real world and it is very important to develop population-specific BP-control protocols that fully consider the population\u27s characteristics, such as age, sex, socio-economic status, compliance with medication, education level, and lifestyle. This randomized trial showed the feasibility and safety of the titration protocol to achieve desirable SBP targets (\u3c 150, \u3c 140, and \u3c 130 mmHg) in a sample of rural, Chinese hypertensive patients. The three BP target groups had similar baseline characteristics. After 6 months of treatment, the mean SBP measured at an office visit was 137.2 mmHg, 131.1 mmHg, and 124.2 mmHg, respectively, in the three groups. Home BP and central aortic BP measurements were also obtained. At 6 months, home BP measurements (2 h after drug administration) showed a mean SBP of 130.9 mmHg in the standard group, 124.9 mmHg in the moderately intensive group, and 119.7 mmHg in the intensive group. No serious adverse events were recorded over the 6-month study period. Rates of adverse events, including dry cough, palpitations, and arthralgia, were low and showed no significant differences between the three groups. This trial provided real-world experience and laid the foundation for a future, large-scale, BP target study. Trial registration: Feasibility Study of the Intensive Systolic Blood Pressure Control; ClinicalTrials.gov, ID: NCT02817503. Registered retrospectively on 29 June 2016
Three-dimensional nanoscopy of whole cells and tissues with in situ point spread function retrieval
Single-molecule localization microscopy is a powerful tool for visualizing subcellular structures, interactions and protein functions in biological research. However, inhomogeneous refractive indices inside cells and tissues distort the fluorescent signal emitted from single-molecule probes, which rapidly degrades resolution with increasing depth. We propose a method that enables the construction of an in situ 3D response of single emitters directly from single-molecule blinking datasets, and therefore allows their locations to be pinpointed with precision that achieves the Cramér-Rao lower bound and uncompromised fidelity. We demonstrate this method, named in situ PSF retrieval (INSPR), across a range of cellular and tissue architectures, from mitochondrial networks and nuclear pores in mammalian cells to amyloid-β plaques and dendrites in brain tissues and elastic fibers in developing cartilage of mice. This advancement expands the routine applicability of super-resolution microscopy from selected cellular targets near coverslips to intra- and extracellular targets deep inside tissues
A Conserved Cysteine Motif Is Critical for Rice Ceramide Kinase Activity and Function
Ceramide kinase (CERK) is a key regulator of cell survival in dicotyledonous plants and animals. Much less is known about the roles of CERK and ceramides in mediating cellular processes in monocot plants. Here, we report the characterization of a ceramide kinase, OsCERK, from rice (Oryza sativa spp. Japonica cv. Nipponbare) and investigate the effects of ceramides on rice cell viability.OsCERK can complement the Arabidopsis CERK mutant acd5. Recombinant OsCERK has ceramide kinase activity with Michaelis-Menten kinetics and optimal activity at 7.0 pH and 40°C. Mg2+ activates OsCERK in a concentration-dependent manner. Importantly, a CXXXCXXC motif, conserved in all ceramide kinases and important for the activity of the human enzyme, is critical for OsCERK enzyme activity and in planta function. In a rice protoplast system, inhibition of CERK leads to cell death and the ratio of added ceramide and ceramide-1-phosphate, CERK's substrate and product, respectively, influences cell survival. Ceramide-induced rice cell death has apoptotic features and is an active process that requires both de novo protein synthesis and phosphorylation, respectively. Finally, mitochondria membrane potential loss previously associated with ceramide-induced cell death in Arabidopsis was also found in rice, but it occurred with different timing.OsCERK is a bona fide ceramide kinase with a functionally and evolutionarily conserved Cys-rich motif that plays an important role in modulating cell fate in plants. The vital function of the conserved motif in both human and rice CERKs suggests that the biochemical mechanism of CERKs is similar in animals and plants. Furthermore, ceramides induce cell death with similar features in monocot and dicot plants
NF45/NF90-mediated rDNA transcription provides a novel target for immunosuppressant development
Herein, we demonstrate that NFAT, a key regulator of the immune response, translocates from cytoplasm to nucleolus and interacts with NF45/NF90 complex to collaboratively promote rDNA transcription via triggering the directly binding of NF45/NF90 to the ARRE2-like sequences in rDNA promoter upon T-cell activation in vitro. The elevated pre-rRNA level of T cells is also observed in both mouse heart or skin transplantation models and in kidney transplanted patients. Importantly, T-cell activation can be significantly suppressed by inhibiting NF45/NF90-dependent rDNA transcription. Amazingly, CX5461, a rDNA transcription-specific inhibitor, outperformed FK506, the most commonly used immunosuppressant, both in terms of potency and off-target activity (i.e., toxicity), as demonstrated by a series of skin and heart allograft models. Collectively, this reveals NF45/NF90-mediated rDNA transcription as a novel signaling pathway essential for T-cell activation and as a new target for the development of safe and effective immunosuppressants
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