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1.
Genome Res ; 34(3): 454-468, 2024 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-38627094

RESUMO

Reference-free genome phasing is vital for understanding allele inheritance and the impact of single-molecule DNA variation on phenotypes. To achieve thorough phasing across homozygous or repetitive regions of the genome, long-read sequencing technologies are often used to perform phased de novo assembly. As a step toward reducing the cost and complexity of this type of analysis, we describe new methods for accurately phasing Oxford Nanopore Technologies (ONT) sequence data with the Shasta genome assembler and a modular tool for extending phasing to the chromosome scale called GFAse. We test using new variants of ONT PromethION sequencing, including those using proximity ligation, and show that newer, higher accuracy ONT reads substantially improve assembly quality.


Assuntos
Nanoporos , Humanos , Análise de Sequência de DNA/métodos , Sequenciamento por Nanoporos/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Software , Genômica/métodos
2.
Diabetologia ; 67(9): 1980-1997, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38879617

RESUMO

AIMS/HYPOTHESIS: Glomerular lipid accumulation is a defining feature of diabetic kidney disease (DKD); however, the precise underlying mechanism requires further elucidation. Recent evidence suggests a role for proprotein convertase subtilisin/kexin type 9 (PCSK9) in intracellular lipid homeostasis. Although PCSK9 is present in kidneys, its role within kidney cells and relevance to renal diseases remain largely unexplored. Therefore, we investigated the role of intracellular PCSK9 in regulating lipid accumulation and homeostasis in the glomeruli and podocytes under diabetic conditions. Furthermore, we aimed to identify the pathophysiological mechanisms responsible for the podocyte injury that is associated with intracellular PCSK9-induced lipid accumulation in DKD. METHODS: In this study, glomeruli were isolated from human kidney biopsy tissues, and glomerular gene-expression analysis was performed. Also, db/db and db/m mice were used to perform glomerular gene-expression profiling. We generated DKD models using a high-fat diet and low-dose intraperitoneal streptozocin injection in C57BL/6 and Pcsk9 knockout (KO) mice. We analysed cholesterol and triacylglycerol levels within the kidney cortex. Lipid droplets were evaluated using BODIPY staining. We induced upregulation and downregulation of PCSK9 expression in conditionally immortalised mouse podocytes using lentivirus and siRNA transfection techniques, respectively, under diabetic conditions. RESULTS: A significant reduction in transcription level of PCSK9 was observed in glomeruli of individuals with DKD. PCSK9 expression was also reduced in podocytes of animals under diabetic conditions. We observed significantly higher lipid accumulation in kidney tissues of Pcsk9 KO DKD mice compared with wild-type (WT) DKD mice. Additionally, Pcsk9 KO mouse models of DKD exhibited a significant reduction in mitochondria number vs WT models, coupled with a significant increase in mitochondrial size. Moreover, albuminuria and podocyte foot process effacement were observed in WT and Pcsk9 KO DKD mice, with KO DKD mice displaying more pronounced manifestations. Immortalised mouse podocytes exposed to diabetic stimuli exhibited heightened intracellular lipid accumulation, mitochondrial injury and apoptosis, which were ameliorated by Pcsk9 overexpression and aggravated by Pcsk9 knockdown in mouse podocytes. CONCLUSIONS/INTERPRETATION: The downregulation of PCSK9 in podocytes is associated with lipid accumulation, which leads to mitochondrial dysfunction, cell apoptosis and renal injury. This study sheds new light on the potential involvement of PCSK9 in the pathophysiology of glomerular lipid accumulation and podocyte injury in DKD.


Assuntos
Nefropatias Diabéticas , Glomérulos Renais , Metabolismo dos Lipídeos , Podócitos , Pró-Proteína Convertase 9 , Animais , Humanos , Masculino , Camundongos , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Metabolismo dos Lipídeos/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Podócitos/metabolismo , Podócitos/patologia , Pró-Proteína Convertase 9/metabolismo , Pró-Proteína Convertase 9/genética
3.
Eur J Nutr ; 63(6): 2121-2135, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38705901

RESUMO

PURPOSE: Recent advances have led to greater recognition of the role of mitochondrial dysfunction in the pathogenesis of chronic kidney disease (CKD). There has been evidence that CKD is also associated with dysbiosis. Here, we aimed to evaluate whether probiotic supplements can have protective effects against kidney injury via improving mitochondrial function. METHODS: An animal model of CKD was induced by feeding C57BL/6 mice a diet containing 0.2% adenine. KBL409, a strain of Lactobacillus acidophilus, was administered via oral gavage at a dose of 1 × 109 CFU daily. To clarify the underlying mechanisms by which probiotics exert protective effects on mitochondria in CKD, primary mouse tubular epithelial cells stimulated with TGF-ß and p-cresyl sulfate were administered with butyrate. RESULTS: In CKD mice, PGC-1α and AMPK, key mitochondrial energy metabolism regulators, were down-regulated. In addition, mitochondrial dynamics shifted toward fission, the number of fragmented cristae increased, and mitochondrial mass decreased. These alterations were restored by KBL409 administration. KBL409 supplementation also improved defects in fatty acid oxidation and glycolysis and restored the suppressed enzyme levels involved in TCA cycle. Accordingly, there was a concomitant improvement in mitochondrial respiration and ATP production assessed by mitochondrial function assay. These favorable effects of KBL409 on mitochondria ultimately decreased kidney fibrosis in CKD mice. In vitro analyses with butyrate recapitulated the findings of animal study. CONCLUSIONS: This study demonstrates that administration of the probiotic Lactobacillus acidophilus KBL409 protects against kidney injury via improving mitochondrial function.


Assuntos
Modelos Animais de Doenças , Lactobacillus acidophilus , Camundongos Endogâmicos C57BL , Mitocôndrias , Probióticos , Insuficiência Renal Crônica , Animais , Lactobacillus acidophilus/fisiologia , Probióticos/farmacologia , Probióticos/administração & dosagem , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Masculino , Rim/efeitos dos fármacos , Rim/metabolismo
4.
Angew Chem Int Ed Engl ; : e202409992, 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39129217

RESUMO

The concept of a lithiophilic electrode proves inadequate in describing carbon-based electrode materials due to their substantial mismatch in surface energy with lithium metal. However, their notable capacity for lithium chemisorption can increase active lithium concentration required for nucleation and growth, thereby enhancing the electrochemical performance of lithium metal anodes (LMAs). In this study, we elucidate the effects of the supersaturated electrode which has high active lithium capacity around equilibrium lithium potential on LMAs through an in-depth electrochemical comparison using two distinct carbon electrode platforms with differing carbon structures but similar two-dimensional morphologies. In the supersaturated electrode, both the dynamics and thermodynamic states involved in lithium nucleation and growth mechanisms are significantly improved, particularly under continuous current supply conditions. Furthermore, the chemical structures of the solid-electrolyte-interface layers (SEIs) are greatly influenced by the elevated surface lithium concentration environment, resulting in the formation of more conductive lithium-rich SEI layers. The improved dynamics and thermodynamics of surface lithium, coupled with the formation of enhanced SEI layers, contribute to higher power capabilities, enhanced Coulombic efficiencies, and improved cycling performances of LMAs. These results provide new insight into understanding the enhancements in heterogeneous lithium nucleation and growth kinetics on the supersaturated electrode.

5.
J Comput Chem ; 44(30): 2332-2346, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37585026

RESUMO

Conformational space annealing (CSA), a global optimization method, has been applied to various protein structure modeling tasks. In this paper, we applied CSA to the cryo-EM structure modeling task by combining the python subroutine of CSA (PyCSA) and the fast relax (FastRelax) protocol of PyRosetta. Refinement of initial structures generated from two methods, rigid fitting of predicted structures to the Cryo-EM map and de novo protein modeling by tracing the Cryo-EM map, was performed by CSA. In the refinement of the rigid-fitted structures, the final models showed that CSA can generate reliable atomic structures of proteins, even when large movements of protein domains were required. In the de novo modeling case, although the overall structural qualities of the final models were rather dependent on the initial models, the final models generated by CSA showed improved MolProbity scores and cross-correlation coefficients to the maps. These results suggest that CSA can accomplish flexible fitting and refinement together by sampling diverse conformations effectively and thus can be utilized for cryo-EM structure modeling.


Assuntos
Proteínas , Modelos Moleculares , Microscopia Crioeletrônica/métodos , Proteínas/química , Conformação Molecular , Domínios Proteicos , Conformação Proteica
6.
Behav Brain Funct ; 19(1): 13, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620941

RESUMO

BACKGROUND: Cross-frequency phase-amplitude coupling (PAC) of cortical oscillations is observed within and across cortical regions during higher-order cognitive processes. Particularly, the PAC of alpha and gamma waves in the occipital cortex is closely associated with visual perception. In theory, gamma oscillation is a neuronal representation of visual stimuli, which drives the duty cycle of visual perception together with alpha oscillation. Therefore, it is believed that the timing of entrainment in alpha-gamma PAC may play a critical role in the performance of visual perception. We hypothesized that transcranial alternating current stimulation (tACS) with gamma waves entrained at the troughs of alpha waves would enhance the dynamic visual acuity (DVA). METHOD: We attempted to modulate the performance of DVA by using tACS. The waveforms of the tACS were tailored to target PAC over the occipital cortex. The waveforms contained gamma (80 Hz) waves oscillating at either the peaks or troughs of alpha (10 Hz) waves. Participants performed computerized DVA task before, immediately after, and 10 min after each stimulation sessions. EEG and EOG were recorded during the DVA task to assess inter-trial phase coherence (ITPC), the alpha-gamma PAC at occipital site and the eye movements. RESULTS: tACS with gamma waves entrained at alpha troughs effectively enhanced DVA, while the tACS with gamma waves entrained at alpha peaks did not affect DVA performance. Importantly, analyses of EEG and EOG showed that the enhancement of DVA performance originated solely from the neuromodulatory effects, and was not related to the modulation of saccadic eye movements. Consequently, DVA, one of the higher-order cognitive abilities, was successfully modulated using tACS with a tailored waveform. CONCLUSIONS: Our experimental results demonstrated that DVA performances were enhanced when tACS with gamma bursts entrained on alpha wave troughs were applied over the occipital cortex. Our findings suggest that using tACS with tailored waveforms, modulation of complex neuronal features could effectively enhance higher-order cognitive abilities such as DVA, which has never been modulated with conventional noninvasive brain stimulation methods.


Assuntos
Procedimentos Cirúrgicos Refrativos , Estimulação Transcraniana por Corrente Contínua , Humanos , Acuidade Visual , Percepção Visual , Movimentos Oculares
7.
Nanotechnology ; 34(32)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37146599

RESUMO

Ambipolar field-effect transistors (FETs) possessing both electron and hole carriers enable implementation of novel reconfigurable transistors, artificial synaptic transistors, and output polarity controllable (OPC) amplifiers. Here, we fabricated a two-dimensional (2D) material-based complementary ambipolar FET and investigated its electrical characteristics. Properties of ohmic-like contacts at source/drain sides were verified from output characteristics and temperature-dependent measurements. The symmetry of electron and hole currents can be easily achieved by optimization of the MoS2or WSe2channels, different from the conventional ambipolar FET with fundamental issues related to Schottky barriers. In addition, we demonstrated successful operation of a complementary inverter and OPC amplifier, using the fabricated complementary ambipolar FET based on 2D materials.

8.
Mol Cell ; 57(2): 349-60, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25544563

RESUMO

Mapping host-pathogen interactions has proven instrumental for understanding how viruses manipulate host machinery and how numerous cellular processes are regulated. DNA viruses such as herpesviruses have relatively large coding capacity and thus can target an extensive network of cellular proteins. To identify the host proteins hijacked by this pathogen, we systematically affinity tagged and purified all 89 proteins of Kaposi's sarcoma-associated herpesvirus (KSHV) from human cells. Mass spectrometry of this material identified over 500 virus-host interactions. KSHV causes AIDS-associated cancers, and its interaction network is enriched for proteins linked to cancer and overlaps with proteins that are also targeted by HIV-1. We found that the conserved KSHV protein ORF24 binds to RNA polymerase II and brings it to viral late promoters by mimicking and replacing cellular TATA-box-binding protein (TBP). This is required for herpesviral late gene expression, a complex and poorly understood phase of the viral lifecycle.


Assuntos
Herpesvirus Humano 8/fisiologia , Transcrição Gênica , Regulação Viral da Expressão Gênica , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , RNA Polimerase II/metabolismo , Proteína de Ligação a TATA-Box/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
9.
BMC Ophthalmol ; 22(1): 426, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348387

RESUMO

BACKGROUND: To compare the surgical outcomes and postoperative complications with and without Ologen collagen matrix augmentation during XEN gel stent implantation. METHODS: We retrospectively analyzed patients who underwent XEN gel stent implantation with an ab externo technique. The amount of intraocular pressure (IOP) reduction, percentage of postoperative complications and additional management, and surgical success defined as IOP reduction greater than 20% compared with the preoperative IOP measurement were compared between Ologen-augmented and non-augmented groups. Groups of patients who underwent XEN gel stent implantation alone and combined with phacoemulsification were analyzed separately. RESULTS: A total 103 eyes of 103 participants were included. Of those, 72 eyes underwent standalone XEN gel stent implantation: 42 eyes with Ologen augmentation (Oloxen group) and 30 eyes without Ologen augmentation (Xen group). Thirty-one eyes underwent XEN gel stent implantation with phacoemulsification: 19 eyes with Ologen augmentation (Phaco-Oloxen group) and 12 eyes without Ologen augmentation (PhacoXen group). The surgical success rate at six months postoperatively was not different between the Oloxen and Xen groups (56.4% vs 43.3%, P > 0.05) or between the Phaco-Oloxen group and PhacoXen group (57.9% vs 41.7%, P > 0.05). The prevalence of postoperative hypotony, 5-fluorouracil injections, use of anti-glaucoma medications, bleb needling, and additional glaucoma surgeries was not different between the Oloxen and Xen groups or between the Phaco-Oloxen and PhacoXen groups when assessed six months postoperatively. CONCLUSIONS: All groups showed significant IOP reduction after XEN gel stent implantation, but there was no significant difference between the Ologen collagen matrix augmented and non-augmented groups in surgical outcomes.


Assuntos
Implantes para Drenagem de Glaucoma , Glaucoma de Ângulo Aberto , Humanos , Colágeno , Glaucoma de Ângulo Aberto/cirurgia , Pressão Intraocular , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Stents , Resultado do Tratamento
10.
Kidney Int ; 100(3): 570-584, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34051264

RESUMO

Ischemia-reperfusion injury is a major cause of acute kidney injury. Recent studies on the pathophysiology of ischemia-reperfusion-induced acute kidney injury showed that immunologic responses significantly affect kidney ischemia-reperfusion injury and repair. Nuclear factor (NF)-ĸB signaling, which controls cytokine production and cell survival, is significantly involved in ischemia-reperfusion-induced acute kidney injury, and its inhibition can ameliorate ischemic acute kidney injury. Using EXPLOR, a novel, optogenetically engineered exosome technology, we successfully delivered the exosomal super-repressor inhibitor of NF-ĸB (Exo-srIĸB) into B6 wild type mice before/after kidney ischemia-reperfusion surgery, and compared outcomes with those of a control exosome (Exo-Naïve)-injected group. Exo-srIĸB treatment resulted in lower levels of serum blood urea nitrogen, creatinine, and neutrophil gelatinase-associated lipocalin in post-ischemic mice than in the Exo-Naïve treatment group. Systemic delivery of Exo-srIĸB decreased NF-ĸB activity in post-ischemic kidneys and reduced apoptosis. Post-ischemic kidneys showed decreased gene expression of pro-inflammatory cytokines and adhesion molecules with Exo-srIĸB treatment as compared with the control. Intravital imaging confirmed the uptake of exosomes in neutrophils and macrophages. Exo-srIĸB treatment also significantly affected post-ischemic kidney immune cell populations, lowering neutrophil, monocyte/macrophage, and T cell frequencies than those in the control. Thus, modulation of NF-ĸB signaling through exosomal delivery can be used as a novel therapeutic method for ischemia-reperfusion-induced acute kidney injury.


Assuntos
Injúria Renal Aguda , Exossomos , Traumatismo por Reperfusão , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/prevenção & controle , Animais , Rim , Camundongos , Camundongos Endogâmicos C57BL , Inibidor de NF-kappaB alfa , Traumatismo por Reperfusão/prevenção & controle
11.
Adv Funct Mater ; 31(43)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34924913

RESUMO

Fiber drawing enables scalable fabrication of multifunctional flexible fibers that integrate electrical, optical and microfluidic modalities to record and modulate neural activity. Constraints on thermomechanical properties of materials, however, have prevented integrated drawing of metal electrodes with low-loss polymer waveguides for concurrent electrical recording and optical neuromodulation. Here we introduce two fabrication approaches: (1) an iterative thermal drawing with a soft, low melting temperature (Tm) metal indium, and (2) a metal convergence drawing with traditionally non-drawable high Tm metal tungsten. Both approaches deliver multifunctional flexible neural interfaces with low-impedance metallic electrodes and low-loss waveguides, capable of recording optically-evoked and spontaneous neural activity in mice over several weeks. We couple these fibers with a light-weight mechanical microdrive (1g) that enables depth-specific interrogation of neural circuits in mice following chronic implantation. Finally, we demonstrate the compatibility of these fibers with magnetic resonance imaging (MRI) and apply them to visualize the delivery of chemical payloads through the integrated channels in real time. Together, these advances expand the domains of application of the fiber-based neural probes in neuroscience and neuroengineering.

12.
BMC Ophthalmol ; 21(1): 453, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34961529

RESUMO

BACKGROUND: To report a rare case of granular cell tumor invading the retina. CASE PRESENTATION: A 56-year-old female complained of blurred vision for 2 weeks in her left eye. An irregular-shaped retinal mass in the inferonasal and extending to the optic disc accompanied by dense exudation and extensive serous retinal detachment was observed. Several intravitreal bevacizumab injections were ineffective for stabilizing retinal exudation and intraocular pressure (IOP). Vitrectomy was performed to re-attach the retina and obtain a tumor biopsy specimen. Histopathological analysis revealed that the intraocular mass was a granular cell tumor. Immunohistochemical studies demonstrated that the tumor was positive for S100 and CD68, focal positive for neurofilaments, but negative for ERG and HMB-45. Local recurrence and distant metastasis were not found, but visual acuity had worsened to no light perception at the last visit due to uncontrolled intraocular pressure and retinal exudation after the surgery. CONCLUSIONS: Granular cell tumor is a rare benign neoplasm, but it can lead to devastating visual loss if it invades the retina adjacent to the optic nerve head.


Assuntos
Tumor de Células Granulares , Neoplasias da Retina , Feminino , Tumor de Células Granulares/diagnóstico , Tumor de Células Granulares/cirurgia , Humanos , Pessoa de Meia-Idade , Retina , Transtornos da Visão , Vitrectomia
13.
Nano Lett ; 20(9): 6535-6541, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32786937

RESUMO

Understanding and modulating proton-mediated biochemical processes in living organisms have been impeded by the lack of tools to control local pH. Here, we design nanotransducers capable of converting noninvasive alternating magnetic fields (AMFs) into protons in physiological environments by combining magnetic nanoparticles (MNPs) with polymeric scaffolds. When exposed to AMFs, the heat dissipated by MNPs triggered a hydrolytic degradation of surrounding polyanhydride or polyester, releasing protons into the extracellular space. pH changes induced by these nanotransducers can be tuned by changing the polymer chemistry or AMF stimulation parameters. Remote magnetic control of local protons was shown to trigger acid-sensing ion channels and to evoke intracellular calcium influx in neurons. By offering a wireless modulation of local pH, our approach can accelerate the mechanistic investigation of the role of protons in biochemical signaling in the nervous system.


Assuntos
Nanopartículas , Prótons , Concentração de Íons de Hidrogênio , Campos Magnéticos , Magnetismo
14.
Medicina (Kaunas) ; 58(1)2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-35056349

RESUMO

Background and Objectives: In this study, we attempted to determine the effects of acupuncture on cardiac remodeling and atrial fibrillation (AF) recurrence rates in patients with AF after electrical cardioversion (EC). Materials and Methods: We randomly assigned 44 patients with persistent AF to an acupuncture group or a sham acupuncture group. An electroacupuncture treatment session was administered once weekly for 12 weeks at four acupuncture points (left PC5, PC6, ST36, and ST37). Results: Among the 44 recruited participants, 16 (treatment group) and 15 (control group) completed the trial. The three-month AF recurrence rate (primary outcome) was not significantly different between the two groups. Following the completion of treatment, patients who had been treated with acupuncture had a significant reduction in left atrial volume index (42.2 ± 13.9 to 36.1 ± 9.7 mL/m2; p = 0.028), whereas no change in atrial size was observed in the sham acupuncture group. No serious adverse events were observed. The AF recurrence rate and cardiac function did not differ significantly between the two groups. At three months, the acupuncture treatment group showed more favorable atrial structural remodeling compared to the sham acupuncture group. Conclusion: In future research on acupuncture in AF management, it is recommended that the inclusion criteria be amended to include only symptomatic AF, that an appropriate control group is designed, and that the acupuncture treatment frequency is increased to several times per week.


Assuntos
Terapia por Acupuntura , Fibrilação Atrial , Fibrilação Atrial/terapia , Cardioversão Elétrica , Humanos , Projetos Piloto , Remodelação Ventricular
15.
Angew Chem Int Ed Engl ; 60(33): 18295-18302, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34097813

RESUMO

Redox cofactors mediate many enzymatic processes and are increasingly employed in biomedical and energy applications. Exploring the influence of external magnetic fields on redox cofactor chemistry can enhance our understanding of magnetic-field-sensitive biological processes and allow the application of magnetic fields to modulate redox reactions involving cofactors. Through a combination of experiments and modeling, we investigate the influence of magnetic fields on electrochemical reactions in redox cofactor solutions. By employing flavin mononucleotide (FMN) cofactor as a model system, we characterize magnetically induced changes in Faradaic currents. We find that radical pair intermediates have negligible influence on current increases in FMN solution upon application of a magnetic field. The dominant mechanism underlying the observed current increases is the magneto-hydrodynamic effect. We extend our analyses to other diffusion-limited electrochemical reactions of redox cofactor solutions and arrive at similar conclusions, highlighting the opportunity to use this framework in redox cofactor chemistry.


Assuntos
Técnicas Eletroquímicas , Mononucleotídeo de Flavina/química , Hidrodinâmica , Campos Magnéticos , Oxirredução , Soluções
16.
Angew Chem Int Ed Engl ; 60(37): 20325-20330, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34265141

RESUMO

Despite the critical role played by carbon monoxide (CO) in physiological and pathological signaling events, current approaches to deliver this messenger molecule are often accompanied by off-target effects and offer limited control over release kinetics. To address these challenges, we develop an electrochemical approach that affords on-demand release of CO through reduction of carbon dioxide (CO2 ) dissolved in the extracellular space. Electrocatalytic generation of CO by cobalt phthalocyanine molecular catalysts modulates signaling pathways mediated by a CO receptor soluble guanylyl cyclase. Furthermore, by tuning the applied voltage during electrocatalysis, we explore the effect of the CO release kinetics on CO-dependent neuronal signaling. Finally, we integrate components of our electrochemical platform into microscale fibers to produce CO in a spatially-restricted manner and to activate signaling cascades in the targeted cells. By offering on-demand local synthesis of CO, our approach may facilitate the studies of physiological processes affected by this gaseous molecular messenger.


Assuntos
Monóxido de Carbono/metabolismo , Técnicas Eletroquímicas , Transdução de Sinais , Monóxido de Carbono/química , Células HEK293 , Humanos
17.
J Cell Mol Med ; 24(22): 13507-13522, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33079436

RESUMO

While the bone morphogenetic protein-7 (BMP-7) is a well-known therapeutic growth factor reverting many fibrotic diseases, including peritoneal fibrosis by peritoneal dialysis (PD), soluble growth factors are largely limited in clinical applications owing to their short half-life in clinical settings. Recently, we developed a novel drug delivery model using protein transduction domains (PTD) overcoming limitation of soluble recombinant proteins, including bone morphogenetic protein-7 (BMP-7). This study aims at evaluating the therapeutic effects of PTD-BMP-7 consisted of PTD and full-length BMP-7 on epithelial-mesenchymal transition (EMT)-related fibrosis. Human peritoneal mesothelial cells (HPMCs) were then treated with TGF-ß1 or TGF-ß1 + PTD-BMP-7. Peritoneal dialysis (PD) catheters were inserted into Sprague-Dawley rats, and these rats were infused intra-peritoneally with saline, peritoneal dialysis fluid (PDF) or PDF + PTD-BMP-7. In vitro, TGF-ß1 treatment significantly increased fibronectin, type I collagen, α-SMA and Snail expression, while reducing E-cadherin expression in HPMCs (P < .001). PTD-BMP-7 treatment ameliorated TGF-ß1-induced fibronectin, type I collagen, α-SMA and Snail expression, and restored E-cadherin expression in HPMCs (P < .001). In vivo, the expressions of EMT-related molecules and the thickness of the sub-mesothelial layer were significantly increased in the peritoneum of rats treated with PDF, and these changes were significantly abrogated by the intra-peritoneal administration of PTD-BMP-7. PTD-BMP-7 treatment significantly inhibited the progression of established PD fibrosis. These findings suggest that PTD-BMP-7, as a prodrug of BMP-7, can be an effective therapeutic agent for peritoneal fibrosis in PD patients.


Assuntos
Proteína Morfogenética Óssea 7/administração & dosagem , Sistemas de Liberação de Medicamentos , Fibrose Peritoneal/tratamento farmacológico , Animais , Biomarcadores , Proteína Morfogenética Óssea 7/química , Modelos Animais de Doenças , Desenho de Fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Humanos , Imuno-Histoquímica , Microscopia Intravital , Masculino , Camundongos , Fibrose Peritoneal/etiologia , Fibrose Peritoneal/metabolismo , Fibrose Peritoneal/patologia , Ratos , Proteínas Recombinantes , Resultado do Tratamento
18.
BMC Plant Biol ; 20(1): 418, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32894043

RESUMO

BACKGROUND: Gender and fertility variation have an impact on mating dynamics in a population because they affect the gene exchange among parental members and the genetic composition of the resultant seed crops. Fertility is the proportional gametic contribution of parents to their progeny. An effective number of parents, derivative of effective population size, is the probability that two alleles randomly chosen from the gamete gene pool originated from the same parent. The effective number of parents is directly related to the fertility variation among parents, which should be monitored for manipulating gene diversity of seed crops. We formulated a fundamental equation of estimating the effective number of parents and applied it to a seed production population. RESULTS: Effective number of parents (Np) was derived from fertility variation (Ψ) considering covariance (correlation coefficient, r) between maternal and paternal fertility. The Ψ was calculated from the coefficient of variation in reproductive outputs and divided into female (ψf) and male (ψm) fertility variation in the population under study. The Np was estimated from the parental Ψ estimated by the fertility variation of maternal (ψf) and paternal (ψm) parents. The gene diversity of seed crops was monitored by Ψ and Np. in a 1.5 generation Pinus koraiensis seed orchard as a case of monoecious species. A large variation of female and male strobili production was observed among the studied 52 parents over four consecutive years, showing statistically significant differences across all studied years. Parental balance curve showed greater distortion in paternal than maternal parents. The Ψ ranged from 1.879 to 4.035 with greater ψm than ψf, and the Np varied from 14.8 to 36.8. When pooled, the relative effective number of parents was improved as 80.0% of the census number. CONCLUSIONS: We recommend the use of fertility variation (i.e., CV, Ψ), Person's product-moment correlation (r), and effective number of parents (Np) as tools for gauging gene diversity of seed crops in production populations. For increasing Np and gene diversity, additional management options such as mixing seed-lots, equal cone harvest and application of supplemental-mass-pollination are recommended.


Assuntos
Produtos Agrícolas/genética , Fertilidade/genética , Flores/genética , Pinus/genética , Pólen/genética , Polinização/genética , Sementes/genética , Melhoramento Vegetal , República da Coreia
19.
Mol Syst Biol ; 15(8): e8875, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31464371

RESUMO

Cell-free expression systems enable rapid prototyping of genetic programs in vitro. However, current throughput of cell-free measurements is limited by the use of channel-limited fluorescent readouts. Here, we describe DNA Regulatory element Analysis by cell-Free Transcription and Sequencing (DRAFTS), a rapid and robust in vitro approach for multiplexed measurement of transcriptional activities from thousands of regulatory sequences in a single reaction. We employ this method in active cell lysates developed from ten diverse bacterial species. Interspecies analysis of transcriptional profiles from > 1,000 diverse regulatory sequences reveals functional differences in promoter activity that can be quantitatively modeled, providing a rich resource for tuning gene expression in diverse bacterial species. Finally, we examine the transcriptional capacities of dual-species hybrid lysates that can simultaneously harness gene expression properties of multiple organisms. We expect that this cell-free multiplex transcriptional measurement approach will improve genetic part prototyping in new bacterial chassis for synthetic biology.


Assuntos
Actinobacteria/genética , Firmicutes/genética , Ensaios de Triagem em Larga Escala , Proteobactérias/genética , Frações Subcelulares/metabolismo , Transcrição Gênica , Actinobacteria/química , Actinobacteria/metabolismo , Firmicutes/química , Firmicutes/metabolismo , Biblioteca Gênica , Regiões Promotoras Genéticas , Biossíntese de Proteínas , Proteobactérias/química , Proteobactérias/metabolismo , Frações Subcelulares/química , Biologia Sintética/métodos
20.
Nephrol Dial Transplant ; 35(3): 438-446, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30615179

RESUMO

BACKGROUND: Recent experimental study reported that proteinuria increases serum phosphate by decreasing biologic activity of fibroblast growth factor 23 (FGF-23). We examined this relationship in a large chronic kidney disease (CKD) cohort and evaluated the combined effect of proteinuria, FGF-23 activity and serum phosphate on CKD progression. METHODS: The activity of FGF-23, measured by the fractional excretion of phosphate (FEP)/FGF-23 ratio, was compared according to the degree of proteinuria in 1909 patients with CKD. Primary outcome was CKD progression defined as ≥50% decline of estimated glomerular filtration rate, doubling of serum creatinine and start of dialysis. RESULTS: There was a negative relationship between 24-h urine protein (24-h UP) and FEP/FGF-23 ratio (γ -0.07; P = 0.005). In addition, after matching variables associated with serum phosphate, patients with more proteinuria had higher serum phosphate (P < 0.001) and FGF-23 (P = 0.012), and lower FEP/FGF-23 ratio (P = 0.007) compared with those with less proteinuria. In the matched cohort, low FEP/FGF-23 ratio was an independent risk factor for CKD progression (hazard ratio 0.87 per 1 log increase; 95% confidence interval 0.79-0.95; P = 0.002), and there was significant interaction between 24-h UP and FEP/FGF-23 ratio (P = 0.039). Furthermore, 24-h UP and serum phosphate also had a significant interaction on CKD progression (P < 0.001). CONCLUSIONS: Proteinuria is associated with decreased biologic activity of FGF-23 and increased serum phosphate. Furthermore, diminished activity of FGF23 is an independent risk factor for renal progression in proteinuric CKD patients.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Fosfatos/sangue , Proteinúria/complicações , Insuficiência Renal Crônica/patologia , Adulto , Idoso , Progressão da Doença , Feminino , Fator de Crescimento de Fibroblastos 23 , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Fosfatos/efeitos adversos , Estudos Prospectivos , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/metabolismo , República da Coreia , Fatores de Risco , Adulto Jovem
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