Publications by authors named "Yu Zheng"

1,015 Publications

  • Page 1 of 1

A design strategy for high mobility stretchable polymer semiconductors.

Nat Commun 2021 Jun 11;12(1):3572. Epub 2021 Jun 11.

Department of Chemical Engineering, Stanford University, Stanford, CA, USA.

As a key component in stretchable electronics, semiconducting polymers have been widely studied. However, it remains challenging to achieve stretchable semiconducting polymers with high mobility and mechanical reversibility against repeated mechanical stress. Here, we report a simple and universal strategy to realize intrinsically stretchable semiconducting polymers with controlled multi-scale ordering to address this challenge. Specifically, incorporating two types of randomly distributed co-monomer units reduces overall crystallinity and longer-range orders while maintaining short-range ordered aggregates. The resulting polymers maintain high mobility while having much improved stretchability and mechanical reversibility compared with the regular polymer structure with only one type of co-monomer units. Interestingly, the crystalline microstructures are mostly retained even under strain, which may contribute to the improved robustness of our stretchable semiconductors. The proposed molecular design concept is observed to improve the mechanical properties of various p- and n-type conjugated polymers, thus showing the general applicability of our approach. Finally, fully stretchable transistors fabricated with our newly designed stretchable semiconductors exhibit the highest and most stable mobility retention capability under repeated strains of 1,000 cycles. Our general molecular engineering strategy offers a rapid way to develop high mobility stretchable semiconducting polymers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-021-23798-2DOI Listing
June 2021

Metabolic profile of main organic acids and its regulatory mechanism in solid-state fermentation of Chinese cereal vinegar.

Food Res Int 2021 Jul 11;145:110400. Epub 2021 May 11.

State Key Laboratory of Food Nutrition and Safety. Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education. College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, People's Republic of China. Electronic address:

Shanxi aged vinegar (SAV), a traditional Chinese cereal vinegar, is produced using solid-state fermentation (SSF) technology. Organic acids are the key flavor compounds of vinegar. However, the metabolic mechanism of organic acids during SSF process is still unclear. In this study, metatranscriptomics was used to explore the metabolic profile of main organic acids in SSF. The results show that carbon metabolism is the dominant pathway during fermentation, among which pyruvate metabolism, glycolysis and starch and sucrose metabolism associated with organic acids were the most abundant. The metabolic pathways of acetic acid and lactic acid shift from acetyl-P and pyruvate pathways at early and middle-early stages of fermentation to acetaldehyde and L-lactaldehyde pathways at later stages, respectively, and Lactobacillus and Acetobacter are the predominant microorganisms contributed to them. Temperature and acetic acid are proven to be the environmental factors that regulate the metabolic activity during SSF. This study sheds new lights on metabolism of flavor substances in the spontaneous ecosystems of traditional fermented food.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.foodres.2021.110400DOI Listing
July 2021

Synapse-specific Lrp4 mRNA enrichment requires Lrp4/MuSK signaling, muscle activity and Wnt non-canonical pathway.

Cell Biosci 2021 Jun 5;11(1):105. Epub 2021 Jun 5.

School of Life Science, Nanchang University, Nanchang, 330031, China.

Background: The neuromuscular junction (NMJ) is a peripheral synapse critical to muscle contraction. Like acetylcholine receptors (AChRs), many essential proteins of NMJ are extremely concentrated at the postjunctional membrane. However, the mechanisms of synapse-specific concentration are not well understood; furthermore, it is unclear whether signaling molecules critical to NMJ formation and maintenance are also locally transcribed.

Results: We studied the β-gal activity encoded by a lacZ cassette driven by the promoter of the Lrp4 gene. As reported for Lrp4 mRNA, β-gal was in the central region in embryonic muscles and at the NMJ after its formation. However, β-gal was no longer in the central areas of muscle fibers in Lrp4 or MuSK mutant mice, indicating a requirement of Lrp4/MuSK signaling. This phenotype could be rescued by transgenic expression of LRP4 with a transmembrane domain but not soluble ECD in Lrp4 mutant mice. β-gal and AChR clusters were distributed in a broader region in lacZ/ECD than that of heterozygous lacZ/+ mice, indicating an important role of the transmembrane domain in Lrp4 signaling. Synaptic β-gal activity became diffused after denervation or treatment with µ-conotoxin, despite its mRNA was increased, indicating synaptic Lrp4 mRNA enrichment requires muscle activity. β-gal was also diffused in aged mice but became re-concentrated after muscle stimulation. Finally, Lrp4 mRNA was increased in C2C12 myotubes by Wnt ligands in a manner that could be inhibited by RKI-1447, an inhibitor of ROCK in Wnt non-canonical signaling. Injecting RKI-1447 into muscles of adult mice diminished Lrp4 synaptic expression.

Conclusions: This study demonstrates that synapse-specific enrichment of Lrp4 mRNA requires a coordinated interaction between Lrp4/MuSK signaling, muscle activity, and Wnt non-canonical signaling. Thus, the study provides a new mechanism for Lrp4 mRNA enrichment. It also provides a potential target for the treatment of NMJ aging and other NMJ-related diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13578-021-00619-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8180081PMC
June 2021

The ALDOA Metabolism Pathway as a Potential Target for Regulation of Prostate Cancer Proliferation.

Onco Targets Ther 2021 24;14:3353-3366. Epub 2021 May 24.

Department of Urology, Guangdong Provincial Institute of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China.

Background: ALDOA plays an essential role in cancer progression in different human cancers; however, its function has not been understood in prostate cancer (PCa).

Methods: Associations of ALDOA expression with clinicopathological features and patient prognosis in PCa were evaluated based on data obtained from the Taylor database and our clinical tissue microarray. The potential roles of ALDOA in malignant progression were verified using a series of in vivo and in vitro experiments after stable ALDOA overexpression and knockdown in DU145 and PC3 cell lines. An aldolase A inhibitor was used to determine the effects of inhibition of ALDOA on PCa cell proliferation.

Results: Higher expression of ALDOA was positively correlated with the incidence of postoperative metastasis and biochemical recurrence (BCR) and may predict poor prognosis in PCa patients. In vivo experiments demonstrated that overexpression of ALDOA could significantly promote cell proliferation, prolong the cell cycle, and significantly reduce the apoptosis rate of PCa cells. Knockdown of expression of ALDOA could inhibit the proliferation and shorten the cell cycle of PCa cells significantly, with no significant effects on cell apoptosis ( > 0.05). In vitro experiments showed that overexpression of ALDOA could significantly promote tumor growth ( < 0.05), while treatment with the Aldolase A inhibitor naphthol AS-E phosphate dose-dependently suppressed the growth of PCa cells ( < 0.01). The analysis of datasets from the Taylor database showed that there was negative regulatory relationship between the expression of ALDOA and MYPT1 ( < 0.001).

Conclusion: Our study revealed that ALDOA played an important role in the progression of PCa. The MYPT1-ALDOA signaling axis may be a new target for the clinical treatment of PCa patients given its negative regulatory relationship. Our study suggests that Aldolase A inhibitors may represent a novel approach to inhibit the growth of PCa.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/OTT.S290284DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8163754PMC
May 2021

Polyphenols Extracted from Shanxi-Aged Vinegar Inhibit Inflammation in LPS-Induced RAW264.7 Macrophages and ICR Mice via the Suppression of MAPK/NF-κB Pathway Activation.

Molecules 2021 May 7;26(9). Epub 2021 May 7.

Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457, China.

Shanxi-aged vinegar, a traditional Chinese grain-fermented food that is rich in polyphenols, has been shown to have therapeutic effects on a variety of diseases. However, there has been no comprehensive evaluation of the anti-inflammatory activity of polyphenols extracted from Shanxi-aged vinegar (SAVEP) to date. The anti-inflammatory activities of SAVEP, both in RAW 264.7 macrophages and mice, were extensively investigated for the potential application of SAVEP as a novel anti-inflammatory agent. In order to confirm the notion that polyphenols could improve inflammatory symptoms, SAVEP was firstly detected by gas chromatography mass spectrometry (GC-MS). In total, 19 polyphenols were detected, including 12 phenolic acids. The study further investigated the protective effect of SAVEP on lipopolysaccharide-induced inflammation in RAW264.7 macrophages and ICR mice. The results showed that compared with those of the model group, SAVEP could remarkably recover the inflammation of macrophage RAW264.7 and ICR mice. SAVEP can normalise the expression of related proteins via the suppression of MAPK/NF-κB pathway activation, inhibiting the expression of iNOS and COX-2 proteins, and consequently the production of inflammatory factors, thus alleviating inflammatory stress. These results suggest that SAVEP may have a potential function against inflammation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules26092745DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8124351PMC
May 2021

Quantum Light Emission from Coupled Defect States in DNA-Functionalized Carbon Nanotubes.

ACS Nano 2021 Jun 1. Epub 2021 Jun 1.

Center for Integrated Nanotechnologies, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States.

Solid-state single-photon sources are essential building blocks for quantum photonics and quantum information technologies. This study demonstrates promising single-photon emission from quantum defects generated in single-wall carbon nanotubes (SWCNTs) by covalent reaction with guanine nucleotides in their single-stranded DNA coatings. Low-temperature photoluminescence spectroscopy and photon-correlation measurements on individual guanine-functionalized SWCNTs (GF-SWCNTs) indicate that multiple, closely spaced guanine defect sites within a single ssDNA strand collectively form an exciton trapping potential that supports a localized quantum state capable of room-temperature single-photon emission. In addition, exciton traps from adjacent ssDNA strands are weakly coupled to give cross-correlations between their separate photon emissions. Theoretical modeling identifies coupling mechanism as a capture of band-edge excitons. Because the spatial pattern of nanotube functionalization sites can be readily controlled by selecting ssDNA base sequences, GF-SWCNTs should become a versatile family of quantum light emitters with engineered properties.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsnano.1c02709DOI Listing
June 2021

Adopting Telehealth during the COVID-19 Era: The Urologist's Perspective.

Urology 2021 May 27. Epub 2021 May 27.

Department of Urology, Medical University of South Carolina, Charleston, SC, USA. Electronic address:

Objective: To evaluate the urology providers' (through a range of training levels) experience utilizing telemedicine given the rapid nationwide implementation of telemedicine in urology practices due to COVID-19. Several studies focusing on the patient's perspective have illustrated that telemedicine is comparable to traditional office visits in terms of cost, communication, and overall satisfaction. However, there is sparse data on the provider's experience.

Methods: With IRB approval, we assessed provider satisfaction with telemedicine at Urology programs in the U.S. through an electronic survey. The 25-question survey was based on the PACT which is a validated 33 question instrument that has been utilized to assess the quality of patient-provider communication in telemedicine. Experience with telemedicine was assessed in two categories: technical aspects and communication with patients. Variables were rated using a 5-point Likert Scale.

Results: There were 144 responses to the survey. 50% of providers reported not receiving any formal training in using telemedicine. This differed significantly by training level with 55% of attendings having had received training vs 20% of residents. Providers felt they would most benefit from training in billing (52%) rather than equipment use (33%) or communication (28%). 87% of providers felt comfortable discussing sensitive topics while only 55% felt comfortable using telehealth to schedule surgery (p<0.001).

Conclusion: Urology providers are generally satisfied with their experience communicating with patients via telemedicine and the majority would opt to continue utilizing telemedicine. Nevertheless, many providers are hesitant to schedule surgery via telemedicine. Providers would benefit from formal training in telemedicine.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.urology.2021.03.051DOI Listing
May 2021

Increased mucin-degrading bacteria by high protein diets leads to thinner mucus layer and aggravates experimental colitis.

J Gastroenterol Hepatol 2021 May 28. Epub 2021 May 28.

Department of Gastroenterology, Xiangya Hospital Central South University, Changsha, Hunan Province, China.

Background And Aim: Westernized high-fat diet increases the risk for inflammatory bowel diseases (IBD), yet with insufficient understanding of the role of high protein diet. We aimed to identify the effect of high protein diets from different dietary proteins (casein, whey protein, soy protein) on experimental colitis and its impact on microbiota, structure and function of colonic mucus layer.

Methods: Female BALB/c mice were fed by standard diet, high casein diet (HCD), high whey protein diet or high soy protein diet for 4 weeks. The susceptibility of dextran sulfate sodium (DSS)-induced colitis in mice and thickness of colonic mucus layer were compared after different dietary interventions, associated with the identification of the reversal effect of broad-spectrum antibiotic intervention (BSA, 0.5g/l of vancomycin and 1g/l of neomycin sulfate, metronidazole and ampicillin in drinking water). Further analysis was performed on the synthesis of mucin, microbiota and sialidase involved in degradation of mucus layer.

Results: High protein diets aggravated acute DSS-induced colitis independent of protein composition, while broad-spectrum antibiotics reversed this effect. HCD significantly altered the composition of bacteria in the colonic mucus layer, especially Bacteroides thetaiotaomicron and total mucin-degrading bacteria; besides, it increased sialidase concentration and reduced the thickness of mucus layer. However, it exhibited no significant effect on the synthesis of Muc2. BSA decreased the abundance of mucin-degrading bacteria and sialidase concentration, while increased the thickness of mucus layer.

Conclusion: High protein diet shifts microbial composition and thickness of colonic mucus layer, leading to the aggravation of acute DSS-induced colitis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jgh.15562DOI Listing
May 2021

Exploring the Inhibitory Effect of Low-frequency Magnetic Fields on Epileptiform Discharges in Juvenile Rat Hippocampus.

Neuroscience 2021 May 24;467:1-15. Epub 2021 May 24.

School of Life Sciences, Tiangong University, Tianjin 300387, China. Electronic address:

Stimulation with a low frequency electromagnetic field (LF-EMF) has proven to represent a powerful method for the suppression of seizures, as demonstrated in select clinical and laboratory studies. However, the mechanism by which LF-EMF suppresses seizures remains unclear. The purpose of the present study was to explore the modulatory effect of LF-EMF on epileptiform discharges (EDs) using rat hippocampal slices and investigate the underlying mechanisms that mediate these effects. EDs in hippocampal slices was induced by magnesium-free (zero-Mg) artificial cerebrospinal fluid (ACSF) and recorded using an in vitro micro-electrode array (MEA). A small sub-decimeter coil was designed and incorporated in a flexible magnetic stimulation device that allowed electromagnetic fields with different parameters to be delivered to slices. After a stable ED event was recorded, magnetic fields of 0.5 Hz (30 min) with a magnetic intensity of 0.13 mT (5 V voltage input) and 0.25 mT (20 V voltage input) were applied. The results indicated that a high-amplitude 0.5 Hz magnetic field could lead to persistent suppression of ictal discharges (IDs), while low-amplitude magnetic fields did not influence IDs. The persistent suppression of complex ED was prevented if the magnetic fields were applied in the presence of 10 μmol/L bicuculline (BIC), a γ-aminobutyric acid type A (GABA) receptor antagonist, while the application of BIC subsequent to a magnetic field application led to the reappearance of ID. The addition of BIC resulted in EDs that had previously been inhibited by magnetic fields, reappearing. Low-frequency magnetic stimulation was able to inhibit the conversion from interictal discharges (IIDs) or preictal discharges (PIDs) to IDs. This suppression was attributed to the modulation of GABA receptor activity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.neuroscience.2021.05.016DOI Listing
May 2021

Membraneless condensates by Rapsn phase separation as a platform for neuromuscular junction formation.

Neuron 2021 May 19. Epub 2021 May 19.

Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH 44106, USA. Electronic address:

Our daily life depends on muscle contraction, a process that is controlled by the neuromuscular junction (NMJ). However, the mechanisms of NMJ assembly remain unclear. Here we show that Rapsn, a protein critical for NMJ formation, undergoes liquid-liquid phase separation (LLPS) and condensates into liquid-like assemblies. Such assemblies can recruit acetylcholine receptors (AChRs), cytoskeletal proteins, and signaling proteins for postsynaptic differentiation. Rapsn LLPS requires multivalent binding of tetratricopeptide repeats (TPRs) and is increased by Musk signaling. The capacity of Rapsn to condensate and co-condensate with interaction proteins is compromised by mutations of congenital myasthenic syndromes (CMSs). NMJ formation is impaired in mutant mice carrying a CMS-associated, LLPS-deficient mutation. These results reveal a critical role of Rapsn LLPS in forming a synaptic semi-membraneless compartment for NMJ formation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.neuron.2021.04.021DOI Listing
May 2021

Circ_0038467 regulates lipopolysaccharide-mediated cell proliferation, apoptosis and inflammatory response by miR-195-5p/TLR4 axis through NF-κB pathway in MRC-5 cells.

Biosci Biotechnol Biochem 2021 May 22. Epub 2021 May 22.

Department of Respiratory, The Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.

Infantile pneumonia (IP) is an acute lower respiratory infection and brings a heavy burden to children health. Circular RNAs (circRNAs) participate in the regulation of pneumonia process. In this research, the effects of circ_0038467 in regulating lipopolysaccharide (LPS)-induced cell injury and underlying mechanism were revealed. Results showed that circ_0038467 expression and TLR4 protein level were upregulated, while miR-195-5p expression was downregulated in LPS-induced MRC-5 cells. Circ_0038467 silencing restored LPS-mediated inhibition on cell proliferation and promotion on apoptosis and inflammatory response. Additionally, circ_0038467 acted as a sponge of miR-195-5p, which was further revealed to target TLR4. MiR-195-5p inhibitor reversed circ_0038467 silencing-mediated influences under LPS treatment. Furthermore, LPS-activated NF-κB pathway was partly blocked by circ_0038467 silencing, which was restrained by TLR4 overexpression. Circ_0038467 silencing protected MRC-5 cells from LPS-induced injury by miR-195-5p/TLR4 axis through NF-κB pathway, providing a theoretical basis for circRNA-directed IP therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/bbb/zbab092DOI Listing
May 2021

Development and review of a sub-millimeter-sized cell-scale micro-magnetic stimulation device.

Biomed Phys Eng Express 2021 Jun 7;7(4). Epub 2021 Jun 7.

School of Life Sciences, Tiangong university, Tianjin 300387, People's Republic of China.

The development of modern micro-processing technology has led to the design and production of sub-millimeter-sized coils. A novel type of micro-magnetic stimulation (MS) regulatory technology has widely been researched in recent years. This technology has several advantages, including small size, no contact between tissues and the metal coil, and high spatial resolution. Considering some problems with theMS control technology in practical applications, different kinds ofMS devices have been developed, including ansingle-pointMS device, animplantable single-pointMs device, a discrete-arrayMS device, and animplantable-arrayMs device. Given the problems that currently exist in the design and implementation of this device, such as the key problems of structural design, implantation method, experimental safety, and reliability of the device, we review the development process in detail. We also discuss the precise targeting advantage of this device, which is likely to be of great significance for wide-ranging applications of magnetic stimulation technology.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1088/2057-1976/ac0409DOI Listing
June 2021

Integrating Emerging Polymer Chemistries for the Advancement of Recyclable, Biodegradable, and Biocompatible Electronics.

Adv Sci (Weinh) 2021 May 20:e2101233. Epub 2021 May 20.

Department of Chemical Engineering, Stanford University, Stanford, CA, 94305-5025, USA.

Through advances in molecular design, understanding of processing parameters, and development of non-traditional device fabrication techniques, the field of wearable and implantable skin-inspired devices is rapidly growing interest in the consumer market. Like previous technological advances, economic growth and efficiency is anticipated, as these devices will enable an augmented level of interaction between humans and the environment. However, the parallel growing electronic waste that is yet to be addressed has already left an adverse impact on the environment and human health. Looking forward, it is imperative to develop both human- and environmentally-friendly electronics, which are contingent on emerging recyclable, biodegradable, and biocompatible polymer technologies. This review provides definitions for recyclable, biodegradable, and biocompatible polymers based on reported literature, an overview of the analytical techniques used to characterize mechanical and chemical property changes, and standard policies for real-life applications. Then, various strategies in designing the next-generation of polymers to be recyclable, biodegradable, or biocompatible with enhanced functionalities relative to traditional or commercial polymers are discussed. Finally, electronics that exhibit an element of recyclability, biodegradability, or biocompatibility with new molecular design are highlighted with the anticipation of integrating emerging polymer chemistries into future electronic devices.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/advs.202101233DOI Listing
May 2021

Metformin ncreases arcolemma ntegrity and meliorates euromuscular eficits in a urine odel of Duchenne uscular ystrophy.

Front Physiol 2021 3;12:642908. Epub 2021 May 3.

Laboratory of Synaptic Development and Plasticity, Institute of Life Science, Nanchang University, Nanchang, China.

Duchenne muscular dystrophy (DMD) is a genetic neuromuscular disease characterized by progressive muscle weakness and wasting. Stimulation of AMP-activated protein kinase (AMPK) has been demonstrated to increase muscle function and protect muscle against damage in dystrophic mice. Metformin is a widely used anti-hyperglycemic drug and has been shown to be an indirect activator of AMPK. Based on these findings, we sought to determine the effects of metformin on neuromuscular deficits in mdx murine model of DMD. In this study, we found metformin treatment increased muscle strength accompanied by elevated twitch and tetanic force of tibialis anterior (TA) muscle in mdx mice. Immunofluorescence and electron microscopy analysis of metformin-treated mdx muscles revealed an improvement in muscle fiber membrane integrity. Electrophysiological studies showed the amplitude of miniature endplate potentials (mEPP) was increased in treated mice, indicating metformin also improved neuromuscular transmission of the mdx mice. Analysis of mRNA and protein levels from muscles of treated mice showed an upregulation of AMPK phosphorylation and dystrophin-glycoprotein complex protein expression. In conclusion, metformin can indeed improve muscle function and diminish neuromuscular deficits in mdx mice, suggesting its potential use as a therapeutic drug in DMD patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fphys.2021.642908DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8126699PMC
May 2021

Aba-Seq: High-Resolution Enzymatic Mapping of Genomic 5-Hydroxymethylcytosine.

Methods Mol Biol 2021 ;2272:13-27

New England Biolabs Inc., Ipswich, MA, USA.

Aba-Seq (DNA modification-dependent restriction endonuclease AbaSI coupled with sequencing) provides a cost-effective and non-chemical based method for the high-resolution mapping of genomic 5-hydroxymethylcytosine (5hmC). The high specificity of the AbaSI enzyme allows sensitive detection of 5hmC in the genome. Here, we describe the Aba-Seq technique that was used for the high-resolution mapping of 5hmC in the genome of mouse embryonic stem cells (E14).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/978-1-0716-1294-1_2DOI Listing
January 2021

Seasonal variability and trends in global type-segregated aerosol optical depth as revealed by MISR satellite observations.

Sci Total Environ 2021 Sep 7;787:147543. Epub 2021 May 7.

State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of CMA, Chinese Academy of Meteorological Sciences, Beijing, 100081, China.

This study utilized a long-term (2001-2018) aerosol optical component dataset retrieved from the Multiangle Imaging Spectroradiometer (MISR), Version 23, to perform comprehensive analyses of the global climatology of seasonal AODs, partitioned by aerosol types (including small-size, medium-size, large-size, spherical, and non-spherical). By dividing eight different AOD bins and performing trend analysis, the seasonal variability and trends in these type-segregated AODs, as well as in the frequency occurrences (FOs) for different AOD bins, globally and over 12 regions of interest, were also investigated. In terms of particle size, small-size aerosol particles (diameter < 0.7 μm) contribute the largest to global extinction in all three seasons except winter. A similar globally dominant role is exhibited by spherical aerosols, which contribute 68.5%, 73.3%, 71.6% and 70.2% to the global total AOD (TAOD) in spring, summer, autumn and winter, respectively, on a global average scale. FOs with different aerosol loading levels suggested that the seasonal FOs tend to decrease progressively with increasing aerosol loading, except for Level 1 (TAOD< 0.05). Examination of the seasonal distribution of FOs revealed that the FO at Level 1 (Level 2, 0.05 < TAOD< 0.15) is much larger in summer/winter (winter/autumn) than in spring/autumn (spring/summer) over most areas of the world. However, the FOs for Level 3 (0.15 < TAOD< 0.25) to Level 8 (TAOD> 1.0) generally exhibit greater intensity in spring/summer than in autumn/winter. Temporal trend analyses showed that the seasonal TAOD experiences a significant decline during 2001-2018 in most regions globally, except in South Asia, the Middle East, and North Africa. Opposite seasonal trends in the above regions are closely related to the increase in FOs in the range of 0.4 < TAOD< 1.0. The global average TAOD shows the most pronounced decline in spring, falling by -10.4% (P < 0.05). Examination of the trends in type-segregated AODs further revealed that the decreases in size-segregated (shape-segregated) AODs all contribute to the decrease in seasonal TAOD, with small-size AOD (spherical AOD) contributing most significantly.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scitotenv.2021.147543DOI Listing
September 2021

The laterodorsal tegmentum-ventral tegmental area circuit controls depression-like behaviors by activating ErbB4 in DA neurons.

Mol Psychiatry 2021 May 14. Epub 2021 May 14.

Department of Neurosciences, School of Medicine, Case Western Reserve University, Cleveland, OH, USA.

Dopamine (DA) neurons in the ventral tegmental area (VTA) are critical to coping with stress. However, molecular mechanisms regulating their activity and stress-induced depression were not well understood. We found that the receptor tyrosine kinase ErbB4 in VTA was activated in stress-susceptible mice. Deleting ErbB4 in VTA or in DA neurons, or chemical genetic inhibition of ErbB4 kinase activity in VTA suppressed the development of chronic social defeat stress (CSDS)-induced depression-like behaviors. ErbB4 activation required the expression of NRG1 in the laterodorsal tegmentum (LDTg); LDTg-specific deletion of NRG1 inhibited depression-like behaviors. NRG1 and ErbB4 suppressed potassium currents of VTA DA neurons and increased their firing activity. Finally, we showed that acute inhibition of ErbB4 after stress attenuated DA neuron hyperactivity and expression of depression-like behaviors. Together, these observations demonstrate a critical role of NRG1-ErbB4 signaling in regulating depression-like behaviors and identify an unexpected mechanism by which the LDTg-VTA circuit regulates the activity of DA neurons.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41380-021-01137-7DOI Listing
May 2021

In-situ formation and self-immobilization of biogenic Fe oxides in anaerobic granular sludge for enhanced performance of acidogenesis and methanogenesis.

Sci Total Environ 2021 Sep 29;787:147400. Epub 2021 Apr 29.

School of Chemistry, Beijing Normal University, Beijing 100875, China.

Addition of ferric oxides into flocculent anaerobic sludge was reported to enhance methanogenesis due to accelerated direct interspecies electron transfer (DIET) between syntrophic microbial communities. However, it is generally hard to incorporate Fe oxides into already matured anaerobic granular sludge (AGS) due to its special aggregated structure. In this study, a novel method was attempted to fast incorporate Fe oxides into AGS through in-situ microbial formation and immobilization of biogenic Fe oxides. Factors influencing the formation of Fe oxides were investigated and effects of Fe oxides on the acidogenic and methanogenic performance of AGS were assessed. Results showed that AGS could form Fe oxides mainly in the form of magnetite and hematite through biological reduction of Fe(III) oxyhydroxide. A maximum loading amount of 83.9 mg Fe/g MLVSS was obtained at pH 7 after contacting with 60 mM Fe(III) oxyhydroxide. The efficiency of electron donors which supported Fe(III) reduction followed the order of pyruvate > propionate > glucose > acetate > lactate > formate. Addition of electron transfer mediators (ETMs) promoted the formation of Fe oxides and their performance followed the order of AQDS > AQC > humics > FMN > riboflavin. Presence of Fe oxides in AGS (134.6 Fe/g VSS) increased the production of volatile fatty acids (VFAs) and methane by 16.28% and 41.94% respectively, comparing to the control. The enhancement may be attributed to increased conductivity and stimulated growth of exoelectrogens (Clostridium and Anaerolinea) and methanogenic endoelectrogens Methanosaeta in granular sludge which may strengthen direct interspecies electron transfer between syntrophic microbial communities. Overall, this study provides an alternative strategy to improve the digestion performance of AGS through in-situ formation and immobilization of biogenic Fe oxides.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scitotenv.2021.147400DOI Listing
September 2021

Shexiang Baoxin Pill, a Proprietary Multi-Constituent Chinese Medicine, Prevents Locomotor and Cognitive Impairment Caused by Brain Ischemia and Reperfusion Injury in Rats: A Potential Therapy for Neuropsychiatric Sequelae of Stroke.

Front Pharmacol 2021 27;12:665456. Epub 2021 Apr 27.

School of Chinese Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China.

Ischemic stroke is a common type of cerebrovascular event and also the leading cause of disability. Post-stroke cognitive impairment occurs frequently in stroke survivors. Shexiang Baoxin Pill (SBP) is a proprietary Chinese medicine, initially used to treat cardiovascular diseases. Herein, we aim to explore the effects of SBP on oxygen glucose deprivation and reoxygenation (OGD/R) in neuronal cells (CATH.a) and cerebral ischemia/reperfusion injury induced post-stroke cognitive impairment in middle cerebral artery occlusion (MCAO) rat model. MCAO rats received two doses of oral SBP treatment (28 or 56 mg/kg) after 1 h of operation and once daily for 2 weeks continuously. Behavioral tests, immunoblotting, and immunofluorescence were examined after 14 days. Current data suggest that SBP enhanced cell viability and downregulated apoptosis via activating the PI3K/Akt signaling pathway in CATH. a cells. Furthermore, 14 days of SBP treatment promoted the recovery of learning and locomotor function in the MCAO rats. SBP up-regulated the expression of p-Akt, p-GSK3β, as well as the expression of NMDAR1, PSD-95, and AMPAR. Also, SBP down-regulated the expression of p-CaMKII. These results indicated that long-term SBP treatment might be a potential option for cognitive impairment induced by the ischemic stroke.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fphar.2021.665456DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8111446PMC
April 2021

Comparison of ELF-EMFs stimulation with current stimulation on the regulation of LTP of SC-CA1 synapses in young rat hippocampus.

Int J Radiat Biol 2021 May 27:1-10. Epub 2021 May 27.

Shanghai Key Laboratory of Multidimensional Information Processing, East China Normal University, Shanghai, China.

Background: Long-term potentiation (LTP) is an important functional indicator for synaptic plasticity. Extremely low frequency electromagnetic fields (ELF-EMFs) are a physical means to regulate LTP, which induce induced currents. It is unknown whether induced current is the key factor when LTP is regulated by ELF-EMFs.New Method: A method is proposed for calculating the current value induced by ELF-EMFs. Then, a comparison of ELF-EMFs with current on the regulation of theta-burst or high-frequency stimulation (TBS/HFS)-LTP was performed.

Results: The LTP after ELF-EMFs and μA current regulation was significantly reduced. The regulatory effect of 0.1 μA current on LTP was similar with 100 Hz/2 mT ELF-EMFs, while 0.2 μA had a stronger regulatory effect than 200 Hz/2 mT on HFS-LTP.Comparison with Existing Methods: Most of the existing methods were used to calculate the induced current in human models, while we present a more accurate model for calculating the induced current induced by ELF-EMFs in the rat brain slices.

Conclusions: This work indicated that μA current and ELF-EMFs stimulation reduced LTP. Also, we demonstrated that the regulatory effect of ELF-EMFs on LTP is not entirely deriving from the induced current, since its magnetic mechanism might have played a certain role.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/09553002.2021.1928781DOI Listing
May 2021

Anaplastic carcinoma showing rhabdoid features combined with ovarian mucinous borderline cystadenoma: a case report and literature review.

J Int Med Res 2021 May;49(5):3000605211013159

Department of Gynecology, Sun Yat-sen University First Affiliated Hospital, Guangzhou, China.

Anaplastic carcinoma in an ovarian tumor (ACOT) is rare. There have been a few controversial cases illustrating the clinical characteristics and prognostic factors of ACOT, which are not well known. A 60-year-old Chinese woman presented with a large pelvic tumor. A transvaginal ultrasound examination showed a large single ovarian cystic tumor with mural nodules and ascites. A gross ovarian mass with a size of approximately 20 × 10×15 cm was found. The content of the ovarian cyst was light yellow and chocolate-like, and a large grayish mural nodule of approximately 10 cm was found on the cyst wall. Histological diagnosis of ovarian mucinous borderline cystadenoma with a mural nodule of anaplastic carcinoma showing rhabdoid features and International Federation of Gynecology and Obstetrics (FIGO) stage IIIa was made. Fifteen months after surgery, the patient had received six courses of paclitaxel and carboplatin. She is still alive without any recurrence of the tumor. Findings from the present case suggest that patients with ACOT and FIGO stage IIIa would benefit from surgery and chemotherapy of paclitaxel and carboplatin. We also review the clinical features and survival rate of patients with ACOT using the Surveillance, Epidemiology, and End Result database, and summarize previously reported treatments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/03000605211013159DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8113938PMC
May 2021

Shannon entropy for time-varying persistence of cell migration.

Biophys J 2021 May 1. Epub 2021 May 1.

Chongqing Key Laboratory of Soft Condensed Matter Physics and Smart Materials, College of Physics, Chongqing University, Chongqing, China. Electronic address:

Cell migration, which can be significantly affected by intracellular signaling pathways and extracellular matrix, plays a crucial role in many physiological and pathological processes. Cell migration is typically modeled as a persistent random walk, which depends on two critical motility parameters, i.e., migration speed and persistence time. It is generally very challenging to efficiently and accurately quantify the migration dynamics from noisy experimental data. Here, we introduce the normalized Shannon entropy (SE) based on the FPS of cellular velocity autocovariance function to quantify migration dynamics. The SE introduced here possesses a similar physical interpretation as the Gibbs entropy for thermal systems in that SE naturally reflects the degree of order or randomness of cellular migration, attaining the maximal value of unity for purely diffusive migration (i.e., SE = 1 for the most "random" dynamics) and the minimal value of 0 for purely ballistic dynamics (i.e., SE = 0 for the most "ordered" dynamics). We also find that SE is strongly correlated with the migration persistence but is less sensitive to the migration speed. Moreover, we introduce the time-varying SE based on the WPS of cellular dynamics and demonstrate its superior utility to characterize the time-dependent persistence of cell migration, which typically results from complex and time-varying intra- or extracellular mechanisms. We employ our approach to analyze experimental data of in vitro cell migration regulated by distinct intracellular and extracellular mechanisms, exhibiting a rich spectrum of dynamic characteristics. Our analysis indicates that the SE and wavelet transform (i.e., SE-based approach) offers a simple and efficient tool to quantify cell migration dynamics in complex microenvironment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bpj.2021.04.026DOI Listing
May 2021

Disorder of Sexual Development Males With XYY in Blood Have Exactly X/XY/XYY Mosaicism in Gonad Tissues.

Front Genet 2021 12;12:616693. Epub 2021 Apr 12.

Center for Diagnosis and Treatment of Rare Diseases, Hunan Children's Hospital, University of South China, Changsha, China.

Y chromosome represents masculinization. The extra Y chromosome of XYY patients usually leads to over-masculinization phenotypes. The occurrence of several DSD cases with XYY in blood is controversial. Is XYY associated with disorder of sex development (DSD)? What is the mechanism behind DSD in males with XYY in blood? To this end, this study retrospectively analyzed blood-karyotype data of 4,437 DSD male children and karyotypes data of 6,259 newborn males as the control. Exome sequencing (ES) was performed to test whether the patients with DSD and with XYY in blood had other variants on known DSD-genes. Testicular biopsy was performed. Fluorescence hybridization (FISH) was used to test whether a sex chromosome mosaicism was present in the oral epithelial cells or gonad tissue of patients with DSD and with XYY in blood. Among 4,437 DSD males who received cytogenetic evaluation, 14 patients with 47,XYY were identified. By contrast, five individuals among the 6,259 controls had 47,XYY. XYY in blood is more frequent among males with DSD than in other males ( = 0.004). The XYY karyotypes were confirmed again by GTG-banding in blood samples and by FISH performed on oral epithelial cells. ES on seven XYY DSD patients was successfully performed, but results did not identify any pathogenic variant on 55 known DSD genes. Gonad biopsy ( = 3) revealed testicular dysplasia and true hermaphroditism. FISH of gonad tissues ( = 3) showed that all of the samples had mosaic for X/XY/XYY. This study is the first to investigate the relationship between XYY in blood and DSD. The knowledge that XYY is in the blood and in oral cells have X/XY/XYY mosaicism in gonadal tissue is new for both researchers and clinicians who seek to understand the genetic basis of DSD males.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fgene.2021.616693DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8072476PMC
April 2021

Deriving time-varying cellular motility parameters via wavelet analysis.

Phys Biol 2021 Jun 9;18(4). Epub 2021 Jun 9.

Chongqing Key Laboratory of Soft Condensed Matter Physics and Smart Materials, College of Physics, Chongqing University, Chongqing, 401331, People's Republic of China.

Cell migration, which is regulated by intracellular signaling pathways (ICSP) and extracellular matrix (ECM), plays an indispensable role in many physiological and pathological process such as normal tissue development and cancer metastasis. However, there is a lack of rigorous and quantitative tools for analyzing the time-varying characteristics of cell migration in heterogeneous microenvironment, resulted from, e.g. the time-dependent local stiffness due to microstructural remodeling by migrating cells. Here, we develop a wavelet-analysis approach to derive the time-dependent motility parameters from cell migration trajectories, based on the time-varying persistent random walk model. In particular, the wavelet denoising and wavelet transform are employed to analyze migration velocities and obtain the wavelet power spectrum. Subsequently, the time-dependent motility parameters are derived via Lorentzian power spectrum. Our results based on synthetic data indicate the superiority of the method for estimating the intrinsic transient motility parameters, robust against a variety of stochastic noises. We also carry out a systematic parameter study and elaborate the effects of parameter selection on the performance of the method. Moreover, we demonstrate the utility of our approach via analyzing experimental data ofcell migration in distinct microenvironments, including the migration of MDA-MB-231 cells in confined micro-channel arrays and correlated migration of MCF-10A cells due to ECM-mediated mechanical coupling. Our analysis shows that our approach can be as a powerful tool to accurately derive the time-dependent motility parameters, and further analyze the time-dependent characteristics of cell migration regulated by complex microenvironment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1088/1478-3975/abfcadDOI Listing
June 2021

MIR210HG Aggravates Sepsis-Induced Inflammatory Response of Proximal Tubular Epithelial Cell via the NF-κB Signaling Pathway.

Yonsei Med J 2021 May;62(5):461-469

Department of Emergency, Jiangsu Taizhou People's Hospital, Taizhou, China.

Purpose: Acute kidney injury (AKI) is a serious complication of sepsis and is characterized by inflammatory response. MicroRNA-210 host gene (MIR210HG) is upregulated in human proximal tubular epithelial cells under treatment of inflammatory cytokines. This study aimed to explore the role of MIR210HG in sepsis-induced AKI.

Materials And Methods: Cell viability was detected by a cell counting kit 8 assay. The levels of proinflammatory cytokines were detected by enzyme-linked immunosorbent assay kits. The protein levels of p65, IκBα, and p-IκBα were examined by western blot analysis. The nuclear translocation of nuclear factor kappa B (NF-κB) was detected by immunofluorescence assay. The histological changes of kidneys were analyzed by hematoxylin and eosin staining assay.

Results: Lipopolysaccharide (LPS) treatment significantly inhibited cell viability and increased productions of proinflammatory cytokines in proximal tubular epithelial cells (HKC-8). Additionally, MIR210HG levels in HKC-8 cells were increased by LPS treatment. MIR210HG silencing inhibited the LPS-induced cell inflammatory response. MIR210HG activated the NF-κB signaling pathway by promoting the phosphorylation of IκBα and nuclear translocation of p65. Rescue assays revealed that the MIR210HG-induced increase of cytokines levels and decline of cell viability were rescued by QNZ treatment. Knockdown of MIR210HG decreased blood urea nitrogen, serum creatinine, and proinflammatory cytokine levels in AKI rats. Moreover, the knockdown of MIR210HG protected against AKI-induced histological changes of kidneys in rats.

Conclusion: MIR210HG promotes sepsis-induced inflammatory response of HKC-8 cells by activating the NF-κB signaling pathway. This novel discovery may be helpful for the improvement of sepsis-induced AKI.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3349/ymj.2021.62.5.461DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8084703PMC
May 2021

Melt extrusion deposition (MED™) 3D printing technology - A paradigm shift in design and development of modified release drug products.

Int J Pharm 2021 Jun 24;602:120639. Epub 2021 Apr 24.

Triastek, Inc., 12 East Mozhou Road, U Park P402, Nanjing, Jiangsu, China; Department of Pharmaceutics and Medicinal Chemistry, Thomas J. Long School of Pharmacy, University of the Pacific, 3601 Pacific Ave, Stockton, CA, United States. Electronic address:

Three-dimensional printing (3DP) technology offers unique advantages for pharmaceutical applications. However, most of current 3D printing methods and instrumentations are not specifically designed and developed for pharmaceutical applications. To meet the needs in pharmaceutical applications for precision, compatibility with a wide range of pharmaceutical excipients and drug materials without additional processing, high throughput and GMP compliance, an extrusion-based 3D printer based on Melt Extrusion Deposition (MED™) 3D printing technology was developed in this study. This technology can process powder pharmaceutical excipients and drugs directly without the need of preparing filament as required by FDM 3D printing. Six different tablet designs based on compartment models were used to demonstrate the precision and reproducibility of this technology. The designed tablets were fabricated using the GMP-compliant MED™ 3D printer and were evaluated in vitro for drug release and in vivo for selected designs using male beagle dogs. Tablet designs with one or more compartments showed versatile release characteristics in modulating the release onset time, release kinetics, duration of release and mode of release. Multiple drugs or formulations were fabricated into a single tablet to achieve independent release kinetics for each drug or to fine-tune the pharmacokinetic profile of a drug. Building upon the theoretical analysis of models, precision and reproducibility of MED™ 3D printing technology, a novel product development approach, 3D printing formulation by design (3DPFbD®) was developed to provide an efficient tool for fast and efficient pharmaceutical product development. The MED™ 3D printing represents a novel and promising technology platform encompassing design and development of modified drug release products and has potential to impact the drug delivery and pharmaceutical product development.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijpharm.2021.120639DOI Listing
June 2021

Assessment of Benchmark Dose in BEAS-2B Cells by Evaluating the Cell Relative Viability with Particulates in Motorcycle Exhaust the Air-liquid Interface Exposure.

Biomed Environ Sci 2021 Apr;34(4):272-281

National Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing 100050, China.

Objective: This study aimed to use an air-liquid interface (ALI) exposure system to simulate the inhalation exposure of motorcycle exhaust particulates (MEPs) and then investigate the benchmark dose (BMD) of MEPs by evaluating cell relative viability (CRV) in lung epithelial BEAS-2B cells.

Methods: The MEPs dose was characterized by measuring the number concentration (NC), surface area concentration (SAC), and mass concentration (MC). BEAS-2B cells were exposed to MEPs at different concentrations ALI and CRV was determined using Cell Counting Kit (CCK-8) assay. BMD software was applied to calculate BMD and the lower limit of benchmark dose (BMDL) according to Akaike Information Coefficient (AIC), with -value based on Hill, Linear, Polynomial, and Power model.

Results: Our results reveal that BMD of NC and SAC were estimated by the best-fitting Hill model, while MC was estimated by Polynomial model. The BMDL for CRV following ALI exposure to MEPs were as follows: 364.2#/cm for NC; 0.662 × 10 nm /cm for SAC; and 0.278 μg/m for MC.

Conclusion: These results indicate that MEPs exposure ALI system induces a dose-dependent decrease of CRV and provides the potential exposure threshold of MEPs in a lung cell model.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3967/bes2021.036DOI Listing
April 2021

Single-Cell Sequencing Reveals the Transcriptome and TCR Characteristics of pTregs and Expanded iTregs.

Front Immunol 2021 31;12:619932. Epub 2021 Mar 31.

Department of Biotherapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China.

Regulatory T cells (Tregs) play a critical role in the maintenance of immune tolerance and tumor evasion. However, the relative low proportion of these cells in peripheral blood and tissues has hindered many studies. We sought to establish a rapamycin-based Treg expansion procedure in patients diagnosed with colorectal cancer and perform single-cell sequencing to explore the characteristics of Treg cells. CD25+ cells enriched from peripheral blood mononuclear cells (PBMC) of colorectal tumor patients were cultured in X-VIVO15 medium, supplemented with 5% human AB serum, L-glutamine, rapamycin, interleukin-2 (IL-2), and Dynabeads human Treg expander for 21 days to expand Tregs. Treg cells with satisfactory phenotype and function were successfully expanded from CD4+CD25+ cells in patients with colorectal cancer. The median expansion fold was 75 (range, 20-105-fold), and >90.0% of the harvest cells were CD4+CD25+CD127 cells. The ratio of CD4+CD25+Foxp3+ cells exceeded 60%. Functional assays showed that iTregs significantly inhibited CD8+T cell proliferation . Single-cell sequencing showed that the transcriptome of pTreg (CD4+CD25+CD127 cells isolated from PBMC of colorectal cancer patients) and iTreg (CD4+CD25+CD127 cells expanded according to the above regimen) cells were interlaced. pTregs exhibited enhanced suppressive function, whereas iTregs exhibited increased proliferative capacity. TCR repertoire analysis indicated minimal overlap between pTregs and iTregs. Pseudo-time trajectory analysis of Tregs revealed that pTregs were a continuum composed of three main branches: activated/effector, resting and proliferative Tregs. In contrast, expanded iTregs were a mixture of proliferating and activated/effector cells. The expression of trafficking receptors was also different in pTregs and iTregs. Various chemokine receptors were upregulated in pTregs. Activated effector pTregs overexpressed the chemokine receptor CCR10, which was not expressed in iTregs. The chemokine CCL28 was overexpressed in colorectal cancer and associated with poor prognosis. CCR10 interacted with CCL28 to mediate the recruitment of Treg into tumors and accelerated tumor progression. Depletion of CCR10+Treg cells from tumor microenvironment (TME) could be used as an effective treatment strategy for colorectal cancer patients. Our data distinguished the transcriptomic characteristics of different subsets of Treg cells and revealed the context-dependent functions of different populations of Treg cells, which was crucial to the development of alternative therapeutic strategies for Treg cells in autoimmune disease and cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fimmu.2021.619932DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8044526PMC
March 2021

Expression, purification and properties of the enzymes involved in lanthanide-dependent alcohol oxidation: XoxF4, XoxF5, ExaF/PedH, and XoxG4.

Methods Enzymol 2021 3;650:81-96. Epub 2021 Mar 3.

Department of Chemical Engineering, University of Washington, Seattle, WA, United States. Electronic address:

In this chapter we describe logistics, protocols and conditions for expression, purification and characterization of Ln-dependent alcohol dehydrogenases representing three distinct phylogenetic clades of these enzymes, classified as XoxF4, XoxF5 and ExaF/PedH. We present data on the biochemical properties of a dozen enzymes, all generated by our group, in a comparative fashion. These enzymes display a range of properties in terms of substrate and metal specificities, pH and ammonium requirement, as well as catalytic constants. In addition, we describe a single novel cytochrome, XoxG4, that likely serves as a natural electron acceptor from XoxF5 in methanotrophs of the Gammaproteobacteria class.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/bs.mie.2021.01.041DOI Listing
March 2021