The development of multiple gene expression systems, especially those based on the physical signals, such as multiple color light irradiations, is challenging. Complementary chromatic acclimation ...(CCA), a photoreversible process that facilitates the control of cellular expression using light of different wavelengths in cyanobacteria, is one example. In this study, an artificial CCA systems, inspired by type III CCA light-regulated gene expression, was designed by employing a single photosensor system, the CcaS/CcaR green light gene expression system derived from Synechocystis sp. PCC6803, combined with G-box (the regulator recognized by activated CcaR), the cognate cpcG2 promoter, and the constitutively transcribed promoter, the P
promoter.
One G-box was inserted upstream of the cpcG2 promoter and a reporter gene, the rfp gene (green light-induced gene expression), and the other G-box was inserted between the P
promoter and a reporter gene, the bfp gene (red light-induced gene expression). The Escherichia coli transformants with plasmid-encoded genes were evaluated at the transcriptional and translational levels under red or green light illumination. Under green light illumination, the transcription and translation of the rfp gene were observed, whereas the expression of the bfp gene was repressed. Under red light illumination, the transcription and translation of the bfp gene were observed, whereas the expression of the rfp gene was repressed. During the red and green light exposure cycles at every 6 h, BFP expression increased under red light exposure while RFP expression was repressed, and RFP expression increased under green light exposure while BFP expression was repressed.
An artificial CCA system was developed to realize a multiple gene expression system, which was regulated by two colors, red and green lights, using a single photosensor system, the CcaS/CcaR system derived from Synechocystis sp. PCC6803, in E. coli. The artificial CCA system functioned repeatedly during red and green light exposure cycles. These results demonstrate the potential application of this CCA gene expression system for the production of multiple metabolites in a variety of microorganisms, such as cyanobacteria.
In this study, we developed a green light-regulated T7 RNA polymerase expression system (T7 RNAP system), to provide a novel and versatile high-expression system for cyanobacteria without using any ...chemical inducer, realizing high expression levels comparable with previously reported for recombinant gene expression in cyanobacteria. The T7 RNAP system was constructed and introduced into
Synechocystis
sp. PCC6803. T7 RNAP was inserted downstream of the
cpcG2
promoter, which is recognized and activated by the CcaS/CcaR two-component green-light-sensing system, to compose a vector plasmid, pKT-CS01, to achieve the induction of T7 RNAP expression only under green light illumination, with repression under red light illumination. The reporter gene, superfolder green fluorescent protein (
sf
GFP), was inserted downstream of the
T7
promoter. Transcriptional analyses revealed that T7 RNAP was induced under green light but repressed under red light. Expression of the
sf
GFP protein derived from pKT-CS01 was observed under green light illumination and was approximately 10-fold higher than that in the control transformant, which expressed
sf
GFP directly under the
cpcG2
promoter, which is directly regulated by CcaS/CcaR, under green light illumination. Comparison with the strong promoter expression systems P
cpc560
and P
trcΔlacO
revealed that the expression of
sf
GFP by the T7 RNAP system was comparable with the levels obtained with strong promoters. These results demonstrated that the green light-regulated T7 RNAP gene expression system will be a versatile tool for future technological platform to regulate gene expression in cyanobacterial bioprocesses.
Kualitas koneksi khususnya pada backbone menjadi tantangan Internet Service Provider (ISP). MPLS berkerja di layer 2,5 OSI yang mampu mempercepat pengiriman paket pada jaringan backbone. MPLS ...melekatkan label pada paket yang dikirimkan. Salah satu layanan dari MPLS adalah traffic engineering yang dibuat dengan protokol RSVP. Terdapat protokol baru untuk memberi label pada paket dan mendukung traffic engineering, yaitu Segment Routing. Penelitian ini menganalisis perbandingan performa traffic engineering dengan RSVP dan Segment Routing. Baik pada penerapan RSVP maupun Segment Routing dibuat tunnel untuk jalur utama dan reroute menuju jalur cadangan. Penelitian dilakukan pada emulator EVE-NG dengan mengambil studi kasus topologi backbone di PT ICON+.Hasil penelitian adalah Segment Routing di MPLS menyederhanakan kinerja dari router dalam hal pelabelan dan dalam memelihara Label Switch Path (LSP), tidak membutuhkan protokol signaling. Hasil pengujian latency pada jalur utama, dengan Segment Routing maupun dengan RSVP mempunyai nilai sama. Sedangkan pada jalur cadangan, nilai latency dari Segment Routing lebih kecil, sehingga Segment Routing dapat mengirim data dengan lebih cepat daripada dengan RSVP. Hasil pengujian packet delivery ratio dan packet loss ratio dengan Segment Routing dan dengan RSVP baik di jalur utama maupun jalur cadangan bernilai sama, yaitu 100% dan 0%. Baik pada jalur utama maupun jalur cadangan, penerapan Segment Routing mempunyai nilai throughput yang lebih besar daripada penerapan RSVP, sehingga Segment Routing dapat mengirim data dengan lebih cepat daripada RSVP. Pada kondisi link mengalami kegagalan saat pengujian, keduanya memiliki 1% packet loss, namun perpindahan jalur dilakukan dengan lebih cepat pada Segment Routing.
Systemic abnormalities cause several complications in diabetes patients. Impaired wound healing is a serious complication that leads to severe foot ulcer and amputation. Mesenchymal stem cells (MSCs) ...have been considered a promising strategy for promoting wound healing due to their paracrine function. However, their poor survival after transplantation limits their therapeutic effect and applications. Salidroside, a glucopyranoside, has been reported to exert cytoprotective effects. Our previous study revealed that salidroside could promote the paracrine function of skeletal muscle cells. However, whether salidroside could improve MSCs survival under hyperglycemic condition and, subsequently, promote wound healing in diabetic model mice remains unknown. Here, we found that salidroside pretreatment effectively reversed the hyperglycemia‐induced suppression of the expression of crucial wound healing factors in MSCs, such as heme oxygenase‐1 (HO‐1), fibroblast growth factor 2 (FGF2), and hepatocyte growth factor (HGF). Salidroside pretreatment also suppressed the hyperglycemia‐induced intracellular reactive oxygen species (ROS) levels in MSCs, thereby lowering the apoptosis rate and enhancing MSCs survival rate. Furthermore, salidroside improved the MSCs migration potential that was impaired under hyperglycemia. in vivo experiments revealed that salidroside pretreatment prior to transplantation significantly enhanced the effect of MSCs in promoting wound closure in diabetic mice. Collectively, our results suggest that pretreatment with salidroside could be an effective strategy to enhance the survival rate and the therapeutic effect of MSCs. Thus, our article suggested a novel, potential MSC‐based strategy for diabetic wound healing. Stem Cells Translational Medicine 2019;8:404–414
Salidroside could restore the expression of HO‐1, FGF2 and HGF in mesenchymal stem cells (MSCs) impaired by hyperglycemia. The restoration of these factors improves the survival rate and migration potential of MSCs, which subsequently enhanced their effect in promoting wound closure in diabetic mice. Thus, salidroside‐pretreated MSCs might be a potential therapeutic strategy for diabetic wound healing.
Background
Takayasu arteritis (TA) is included in large vessel vasculitis with unknown aetiopathogenesis. TA is one of the rare diseases with a predilection for young women. The diagnosis of TA is ...difficult due to variation in clinical presentations and non-specific initial symptoms. This case demonstrates rare TA in a young male with congestive heart failure as the predominant manifestation.
Case presentation
We report a 26-year-old male presented with severe dyspnea, palpitation, orthopnea, paroxysmal nocturnal dyspnea, and claudication in the left arm. Four limbs blood pressure discrepancy was present. Chest X-ray showed cardiomegaly with calcification aortic arch and pulmonary edema. Echocardiography revealed that left ventricular ejection fraction decreased with severe aortic and mitral valve regurgitation. Computed tomography angiography showed stenosis of the left common carotid artery and total occlusion of the left subclavian artery with collateral artery. There was vascular thickness and calcification from the peri-aortic valve, ascending aorta, aortic arch, and thoracic descending aorta until abdominal aorta with high-grade stenosis on the inferior side of the renal artery branching accompanied by a post-stenotic dilatation.
Conclusions
This patient’s heart failure was precipitated by secondary hypertension and aortic regurgitation caused by vasculitis of TA. In general, there is no difference in the management of congestive heart failure in patients with TA. Optimized pharmacology therapy with combination steroid and methotrexate successfully inducing remission of TA after 3-months follow-up.
Therapeutic angiogenesis has been considered as a potential strategy for treating peripheral artery diseases including hind-limb ischemia (HLI); however, no effective drug-based treatment is ...currently available. Here we showed that intramuscular administration of salidroside, an active compound of Chinese herb Rhodiola, could robustly enhance blood perfusion recovery by promoting neovascularization in HLI mice. We revealed that salidroside promoted skeletal muscle cell migration and paracrine function through inhibiting the transcriptional level of prolyl-hydroxylase domain 3 (PHD3) without affecting PHD1 and PHD2. Paracrine signals from salidroside-treated skeletal muscle cells enhanced endothelial and smooth muscle cells migration, while inhibition of FGF2/FGF2R and PDGF-BB/PDGFR-β pathways abolished this effect, as well as neovascularization in HLI mice. Furthermore, we elucidated that salidroside inhibition on PHD3 might occur through estrogen receptor alpha (ERα). Together, our findings highlights the potential application of salidroside as a novel pharmalogical inhibitor of ERα/PHD3 axis for therapeutic angiogenesis in HLI diseases.
The purpose of this community service is to provide an understanding of the community on the impact of the use of social media in the current era of information disclosure. This is done so that ...people do not abuse the use of social media and are able to wisely utilize social media itself so as not to cause negative effects. Partners of community service activities are residents of Pringgokusuman, Gedongtengen, Yogyakarta. Education provided includes an understanding of the negative and positive impacts of using social media, the role of families, especially parents, in supervising the use of social media and the legal rules used to overcome problems arising from the use of social media. Many impacts arising from the use of social media. The negative impacts of using social media must be immediately prevented and acted upon because the negative impacts are spread very quickly and are detrimental to users and the community. In addition there are also positive impacts arising from the use of social media that can provide developments both in terms of social and material for the community.
As one of the most severe manifestations of diabetes, vascular complications are the main causes of diabetes-related morbidity and mortality. Hyperglycemia induces systemic abnormalities, including ...impaired angiogenesis, causing diabetic patients to be highly susceptible in suffering hindlimb ischemia (HLI). Despite its severe prognosis, there is currently no effective treatment for diabetic HLI. Skeletal muscle cells secrete multiple angiogenic factors, hence, recently are reported to be critical for angiogenesis; however, hyperglycemia disrupted the paracrine function in skeletal muscle cells, leading to the impaired angiogenesis potential observed in diabetic patients. The present study showed that tyrosol, a phenylethanoid compound, suppresses accumulation of intracellular reactive oxygen species (ROS) caused by hyperglycemia, most plausibly by promoting heme oxygenase-1 (HO-1) expression in skeletal muscle cells. Consequently, tyrosol exerts cytoprotective function against hyperglycemia-induced oxidative stress in skeletal muscle cells, increases their proliferation vigorously, and simultaneously suppresses apoptosis. Furthermore, tyrosol grossly increases the secretion of vascular endothelial growth factor-A (VEGF-A) and platelet-derived growth factor-BB (PDGF-BB) from skeletal muscle cells. This leads to enhanced proliferation and migration capabilities of vascular endothelial and smooth muscle cells, two types of cells that are responsible in forming blood vessels, through cell-cell communication. Finally,
experiment using the diabetic HLI mouse model showed that tyrosol injection into the gastrocnemius muscle of the ischemic hindlimb significantly enhances the formation of functional blood vessels and subsequently leads to significant recovery of blood perfusion. Overall, our findings highlight the potential of the pharmacological application of tyrosol as a small molecule drug for therapeutic angiogenesis in diabetic HLI patients.
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