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1.
Carbohydr Polym ; 240: 116283, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32475567

RESUMO

In this study, nanocellulose was extracted from indigo-dyed denim fabric and the resultant nanocellulose properties were evaluated in comparison with those derived from bleached cotton fabric and wood pulp in order to investigate the potential of recycling denim waste for nanocellulose production and application. Sulfuric acid hydrolysis and (2,2,6,6-tetramethylpiperidin-1-yl) oxyl (TEMPO)-oxidation were utilized to produce cellulose nanocrystals (CNC) and cellulose nanofibers (TOCN), respectively. A stable CNC suspension with blue color was obtained after acid hydrolysis and the TEMPO process yielded colorless TOCN. The denim-derived nanocellulose possessed similar yield, morphology, size, crystallinity, and thermal stability to those derived from bleached cotton but higher crystallinity and thermal stability compared to the nanocellulose from wood pulp. When used to reinforce polyvinyl alcohol film, the blue indigo-CNC not only enhanced mechanical properties of the film but also provided the film with outstanding UV blocking.

2.
Bioresour Technol ; 311: 123478, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32446232

RESUMO

The microbial separator (MS) was promising alternative of ion exchange membrane for biocathode microbial electrochemical system (MES). Four microbial separators developed from porous matrixes were equipped in biocathode MESs. The power generation of MESs responded to cross-separator transfer characters of ions, dissolved oxygen (DO) and chemical oxygen demand (COD). The MES with carbon felt (CF) obtained 31% higher maximum power density at 70 ± 3 mW m-2 and 51% higher current density at 271 ± 21 mA m-2 than those of cation exchange membrane (CEM) separator. All MSs showed higher ionic conductivity than CEM. However, the power variation was mainly due to cathodic equilibrium potential changes rather than internal resistance. The power density demonstrated negative correlation with mass transfer coefficients of DO and COD. The cross-separator transfer of COD caused cathode variation and was identified as the primary parameter for further optimization of MES with microbial separators.

3.
Mol Phylogenet Evol ; 149: 106847, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32380285

RESUMO

The family Epicopeiidae is a small group of day-flying moths, known for mimicking many different groups of butterflies and moths. So far, there still lacks a reliable phylogenetic framework of Epicopeiidae that is necessary to our understanding of the evolutionary process of their mimicry. In this study, we sequenced 94 nuclear protein-coding markers for 56 epicopeiid samples and 11 outgroups, covering all ten genera of Epicopeiidae. We used homemade PCR-generated baits to capture target sequences, which allowed us to utilize old and dried specimens that were difficult to handle by conventional PCR + Sanger sequencing. Maximum likelihood and Bayesian analyses of the newly obtained dataset (86,388 bp) at both DNA and protein levels produced identical phylogenies with strong support. The non-mimicry genus Deuveia is the sister group of other epicopeiid genera. Epicopeia and Nossa are not monophyletic, and these two genera nest together to form a clade. We also estimated divergence times of Epicopeiidae and found that their initial diversification happened in Eocene about 41 million years ago. The ancestral state reconstruction of mimicry type for this family suggested that thelast common ancestor of epicopeiid moths is non-mimetic, and the Riodinidae-mimicry type evolved first. In summary, our work provides a comprehensive and robust time-calibrated phylogeny of Epicopeiidae that provides a sound framework for revising their classification and interpreting character evolution.

4.
J Evid Based Integr Med ; 25: 2515690X20913267, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32297524

RESUMO

Food-medicine plants play an important role in providing nutrition and treating chronic diseases, especially in many minority communities and developing regions. The coastal region of South China has abundant resources of medicinal plants. A long history of cross-cultural medicinal practices among different minority groups has facilitated the development of a remarkable dietary culture by using food-medicine plants. However, integrative ethnobotanical research on both nutritional and functional properties of the food-medicine plants in this region is still limited. In this study, 27 commonly used wild food-medicine plants were recorded and analyzed from the coastal region of South China. Most of them are good sources for calcium (47.83-1099.89 mg/100 g fresh weight), dietary fiber (3.00-31.87 mg/100 g fresh weight), iron (1.17-24.73 mg/100 g fresh weight), and vitamin C (0.44-68.32 mg/100 g fresh weight). Solanum americanum has the highest average nutritive value and is also considered to be good sources for proteins (7.90 g/100 g fresh weight). Medicinal properties of the studied species can be classified into 8 categories: treatment of the damp-heat syndrome, digestive diseases, urologic diseases, arthropathy, respiratory diseases, gynecological diseases, snake or insect bites, and uses as a tonic. Treating the damp-heat syndrome or expelling warm pathogenic factors is the most commonly used ethnomedicinal practice in the study area. The present study highlights that the local ethnomedicinal practices are deeply influenced by local natural conditions and customs. Food-medicine plants with superior key nutrients have been used regularly in the diet as medicinal food to alleviate common endemic diseases.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32325783

RESUMO

: Objective: To determine the characteristics of members of online diabetes communities as well as those factors affecting the provision and acceptance of social support. Methods: A cross-sectional STAR questionnaire survey was conducted among patients with diabetes who were members of online diabetes groups. Univariate and multivariate binary logistic regression analysis were adopted to explore the relative analysis of providing and accepting social support compared with the characteristics of members in virtual diabetics' groups. Results: A total of 1297 respondents were collected. The map distribution of patients in China was mainly located in the Guangdong, Jiangsu, Shandong, Henan, and Hebei provinces. As for their demographic characteristics, respondents had diabetes or prediabetes and were between the ages of 21 and 50 years (Median age was 35.0 (interquartile range from 28.0 to 44.0)). Most respondents were married and lived in cities. The education level of patients was mainly distributed throughout junior high, technical secondary, high school, junior college, and undergraduate levels. Age, marital status, and education level varied by gender, and the total score of the patients aged 41 to 50 for social support had a statistical significance between male and female. In addition, when group members were in junior high school or below, or were undergraduate students, their total social support scores varied by gender. Binary logistic regression showed that in 21 independent variables the total score and the total score grade of relationship intensity in the online group and reorganize of age were significant. The patients' social support acceptance of the map of respondents score grading of relationship intensity in the online group was 5.420 times higher than that of the lower score grading of relationship intensity in the group. At the same time, the patients' social support acceptance of the patients at the age of less than or equal to 31 years old was 19.608 times higher than that of group members aged more than 31 years old. Conclusion: Age and education background of the patients affects scores of social supports between males and females. The higher the total score and the score grade of relationship intensity in the online group, the higher the patients' social support acceptance. The younger patients had a better utilization of social support.

6.
FASEB J ; 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32298026

RESUMO

Mammalian immune responses are initiated by "danger" signals--immutable molecular structures known as PAMPs. When detected by fixed, germline encoded receptors, pathogen-associated molecular pattern (PAMPs) subsequently inform the polarization of downstream adaptive responses depending upon identity and localization of the PAMP. Here, we report the existence of a completely novel "PAMP" that is not a molecular structure but an antigenic pattern. This pattern--the incidence of peptide epitopes with stretches of 100% sequence identity bound to both dendritic cell (DC) major histocompatibility (MHC) class I and MHC class II--strongly induces TH 1 immune polarization and activation of the cellular immune response. Inherent in the existence of this PAMP is the concomitant existence of a molecular sensor complex with the ability to scan and compare amino acid sequence identities of bound class I and II peptides. We provide substantial evidence implicating the multienzyme aminoacyl-tRNA synthetase (mARS) complex and its AIMp1 structural component as the key constituents of this complex. The results demonstrate a wholly novel mechanism by which T-helper (TH ) polarization is governed and provide critical information for the design of vaccination strategies intended to provoke cell-mediated immunity.

7.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 36(2): 104-110, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32314706

RESUMO

Objective To explore the expression of renal cortex bone morphogenetic protein and activating protein membrane binding inhibitor (BAMBI), NLR family pyrin domain containing 3 (NLRP3), apoptosis-associated speck like protein containing a CARD-2 (ASC-2), caspase-1, inflammatory mediators and related fibrosis markers in renal cortex of diabetic mellitus (DM) rats treated with insulin. Methods SD rats were randomly divided into 3 groups: a normal control group, a DM group and an insulin treatment group. Each group included 8 rats. The DM rat model was established by streptozotocin (STZ). Four weeks after STZ injection, the rats in the insulin treatment group was subcutaneously injected with insulin at the dose of 8 U/kg once, three times each day for successive 6 weeks, and then sacrificed finally. The expression of BAMBI, NLRP3 and epithelial cadherin (E-cadherin) in the renal cortex were detected by immunohistochemistry. The expression of BAMBI, NLRP3, ASC-2, caspase-1, α-smooth muscle actin (α-SMA), fibronectin (FN) and type IV collagen (Col4) in the renal cortex were detected by Western blot analysis. The mRNA levels of BAMBI and NLRP3 in the renal cortex were measured by real-time quantitative PCR, and the levels of interleukin-1ß (IL-1ß) and IL-18 in the renal cortex were tested by ELISA. The correlation between BAMBI and NLRP3 was analyzed by Spearman method. Results Compared with the normal control group, the expression of NLRP3, ASC-2, caspase-1, α-SMA, FN and Col4 significantly increased, but BAMBI and E-cadherin significantly decreased in the renal cortex of DM group. However, the expression of NLRP3, ASC-2, caspase-1, α-SMA, FN, Col4, IL-1ß and IL-18 in the insulin-treated group were lower than those in the DM group, but the expression of BAMBI and E-cadherin were higher. According to the correlation analysis, there was a negative correlation between the expression of BAMBI and NLRP3 in the DM group and insulin treatment group. Conclusion Insulin can restore the expression of BAMBI in the renal cortex of DM rats, and then inhibit the activation of NLRP3, thus reducing the renal inflammatory response in the kidney of DM rats and preventing or delaying the progression of diabetic nephropathy.

8.
Mol Phylogenet Evol ; 148: 106807, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-32268200

RESUMO

Snakes are one of the most diverse groups of terrestrial vertebrates, with approximately 3500 extant species. A robust phylogeny and taxonomy of snakes is crucial for us to know, study and protect them. For a large group such as snakes, broad-scale phylogenetic reconstructions largely rely on data integration. Increasing the compatibility of the data from different researches is thus important, which can be facilitated by standardization of the loci used in systematic analyses. In this study, we proposed a unified multilocus marker system for snake systematics by conflating 5 mitochondrial markers, 19 vertebrate-universal nuclear protein coding (NPC) markers and 72 snake-specific noncoding intron markers. This marker system is an addition to the large squamate conserved locus set (SqCL) for studies preferring a medium-scale data set. We applied this marker system to over 440 snake samples and constructed the currently most comprehensive systematic framework of the snakes in China. Robust snake phylogenetic relationships were recovered at both deep and shallow evolutionary depths, demonstrating the usefulness of this multilocus marker system. Discordance was revealed by a parallel comparison between the snake tree based on the multilocus marker system and that based on only the mitochondrial loci, highlighting the necessity of using multiple types of markers to better understand the snake evolutionary histories. The divergence times of different snake groups were estimated with the nuclear data set. Our comprehensive snake tree not only confirms many important nodes inferred in previous studies but also contributes new insights into many snake phylogenetic relationships. Suggestions are made for the current Chinese snake taxonomy.

9.
Artigo em Inglês | MEDLINE | ID: mdl-32182423

RESUMO

Optical coatings with controllable ultralow refractive indices are of profound significance in optical areas. However, it remains a challenge to fabricate such coatings using a simple method. Here we develop an effective and simple approach to create ultra-low-index coatings. This approach was based on a modified sol-gel process, with a key process that involved the aggregation of silica nanoparticles via the addition of a polymer surfactant (e.g., polyvinylpyrrolydone) in sols before coating. The approach involves three steps: the synthesis of silica sols under ammonia catalysis in ethanol (Stöber method), the addition of polyvinylpyrrolydone in the silica sols to induce the aggregation of the silica nanoparticles, and the formation of ultra-low-index coatings by depositing the aggregated silica sols on substrates. Through varying the aggregation extent, this approach produced coatings with controllable refractive indices ranging from 1.17 to 1.07. To the best of our knowledge, the minimum index value of 1.07 from our coating is among the lowest refractive indices ever reported. The ultra-low-index coatings demonstrated excellent optical properties, with which perfect quarter-wavelength antireflection coatings (maximum transmittance ∼100%) and broadband antireflection coatings (transmittance >98% from 400 to 1100 nm) can be prepared. One advantage of the antireflection coatings is that their transmission is less dependent on the refractive index and the thickness of the stacking layer, which make it promising in large-scale production. Moreover, the coatings can be made hydrophobic (water contact angle 136°) by exposing the coatings to a hexamethyldisilazane atmosphere, exhibiting high environmental stability in a humid environment. The aggregation of silica nanoparticles in sol-gel processes provides a scalable alternative to the current approaches for creating ultra-low-index coatings.

10.
Mol Phylogenet Evol ; 146: 106753, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32028033

RESUMO

The torrent frog genus Amolops contains nearly sixty species distributed in swift mountain streams throughout southeast Asia. The taxonomy of this genus has proven complicated due to unstable morphological diagnostic characters. The relationships of Amolops species and species groups were not readily resolved with a small number of molecular markers. Here, we applied the novel AFLP-Capture approach and acquired two large datasets (242 anonymous nuclear sequences and the mitochondrial genome) from 70 Chinese Amolops samples to study their relationships. The phylogenies inferred from the nuclear data and the mitochondrial data were both robust and revealed a primary phylogenetic split between eastern and western Chinese Amolops species. The relationships of the six species groups were clarified. While the three species groups in east China (the A. ricketti, A. daiyunensis and A. hainanensis groups) were monophyletic, the three species groups in the west (the A. mantzorum, A. monticola and A. marmoratus groups) were not monophyletic, suggesting a need for further investigation and revision. The robust phylogenies also provided new insights into species relationships, especially for the A. mantzorum group, which has been difficult to resolve due to multiple speciation events occurring approximately 7-8 million years ago. The divergence times estimated with the nuclear data indicated that the ancestor of the Chinese Amolops appeared in the late Eocene or early Oligocene, and that speciation events in the Chinese Amolops were often related to geological events (e.g. the uprising of mountains and the formation of islands). By including the mitochondrial sequences from GenBank, a more comprehensive Amolops phylogeny was constructed that reflected the origin of the Chinese Amolops. Based on all these results, a dispersal scenario of the torrent frogs was hypothesized. Our research serves as the first example of using AFLP-Capture to obtain a large amount of data for shallow-scale phylogenetic and taxonomic studies, which should be useful for other nonmodel organism groups.

11.
Mol Biol Evol ; 37(6): 1577-1592, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32027372

RESUMO

Pikas are widely distributed in the Northern Hemisphere and are highly adapted to cold and alpine environments. They are one of the most complex and problematic groups in mammalian systematics, and the origin and evolutionary history of extant pikas remain controversial. In this study, we sequenced the whole coding sequences of 105 pika samples (29 named species and 1 putative new species) and obtained DNA data for more than 10,000 genes. Our phylogenomic analyses recognized four subgenera of extant pikas: Alienauroa, Conothoa, Ochotona, and Pika. The interrelationships between the four subgenera were strongly resolved as (Conothoa, (Alienauroa, (Ochotona, Pika))), with the mountain group Conothoa being the sister group of all other pikas. Our divergence time and phylogeographic analyses indicated that the last common ancestor of extant pikas first occurred on in the middle Miocene, ∼14 Ma. The emergence of opportunities related to the climate, food supply, and spreading paths in concert promoted the dispersal of pikas from the Qinghai-Tibetan Plateau (QTP) to other parts of Eurasia and North America. We found that the genes that were positively selected in the early evolution of pikas were most concentrated in functional categories related to cold tolerance. These results suggest that the QTP may have served as a training ground for cold tolerance in early pikas, which gives pikas a great advantage when the climate continued to cool after the middle Miocene. Our study highlights the importance of the QTP as a center of origin for many cold-adapted animals.

12.
Mol Biol Evol ; 37(3): 881-892, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31638156

RESUMO

Incomplete lineage sorting (ILS) is an important factor that causes gene tree discordance. For gene trees of three species, under neutrality, random mating, and the absence of interspecific gene flow, ILS creates a symmetric distribution of gene trees: the gene tree that accords with the species tree has the highest frequency, and the two discordant trees are equally frequent. If the neutral condition is violated, the impact of ILS may change, altering the gene tree distribution. Here, we show that under purifying selection, even assuming that the fitness effect of mutations is constant throughout the species tree, if differences in population size exist among species, asymmetric distributions of gene trees will arise, which is different from the expectation under neutrality. In extremes, one of the discordant trees rather than the concordant tree becomes the most frequent gene tree. In addition, we found that in a real case, the position of Scandentia relative to Primate and Glires, the symmetry in the gene tree distribution can be influenced by the strength of purifying selection. In current phylogenetic inference, the impact of purifying selection on the gene tree distribution is rarely considered by researchers. This study highlights the necessity of considering this impact.

13.
Front Genet ; 10: 1198, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824578

RESUMO

Due to the maternal inheritance of cytoplasm, using foxtail millet [Setaria italica (L.) P. Beauv.] male sterile lines with a single cytoplasmic source as the female parent will inevitably lead to a narrow source of cytoplasm in hybrids, which may make them vulnerable to infection by cytoplasm-specific pathogens, ultimately leading to destructive yield losses. To assess cytoplasmic genetic diversity in plants, molecular markers derived from chloroplast DNA (cpDNA) have been used. However, such markers have not yet been applied to foxtail millet. In this study, we designed and screened nine pairs of polymorphic foxtail millet-specific primers based on its completely sequenced cpDNA. Using these primers, we analyzed the genetic diversity and cytoplasmic types of 130 elite foxtail millet parental lines collected in China. Our results revealed that the cytoplasmic genetic diversity of these accessions was low and needs to be increased. The parental lines were divided into four cytoplasmic types according to population structure analysis and a female parent-derivative evolutionary graph, indicating that the cytoplasmic types of elite foxtail millet lines were rather limited. A principal component analysis (PCA) plot was linked with the geographic and ecological distribution of accessions for each cytoplasmic type, as well as their basal maternal parents. Collectively, our results suggest that enriching cytoplasmic sources through the use of accessions from diverse ecological regions and other countries as the female parent may improve foxtail millet breeding programs, and prevent infection by cytoplasm-specific pathogens.

14.
Sci Rep ; 9(1): 16227, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700055

RESUMO

The complexity of the leaf constitution of foxtail millet (Setaria italica (L.) P. Beauv.) makes it difficult to obtain high-purity cpDNA. Here, we developed a protocol to isolate high-quality cpDNA from foxtail millet and other crops. The new protocol replaces previous tissue grinding and homogenization by enzyme digestion of tiny leaf strips to separate protoplasts from leaf tissue and protects chloroplasts from damage by undue grinding and homogenization and from contamination of cell debris and nuclear DNA. Using the new protocol, we successfully isolated high-quality cpDNAs for whole-genome sequencing from four foxtail millet cultivars, and comparative analysis revealed that they were approximately 27‰ longer than their reference genome. In addition, six cpDNAs of four other species with narrow and thin leaf blades, including wheat (Triticum aestivum L.), maize (Zea may L.), rice (Oryza sativa L.) and sorghum (Sorghum bicolor (L.) Moench), were also isolated by our new protocol, and they all exhibited high sequence identities to their corresponding reference genomes. A maximum-likelihood tree based on the chloroplast genomes we sequenced here was constructed, and the result was in agreement with previous reports, confirming that these cpDNA sequences were available for well-supported phylogenetic analysis and could provide valuable resources for future research.

15.
Zootaxa ; 4591(1): zootaxa.4591.1.1, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31716071

RESUMO

Actias selene (Hübner) is an important silk-spinning moth. Like other moths, it has innate immunity but no acquired immunity. However, there are few studies on immune-related genes of A. selene. Here, differential expression RNAseq experiment was employed to examine the genes related to different metabolic pathways and to explore the immune mechanism of the A. selene post Beauveria bassiana (Bb) and Micrococcus luteus (ML) stimuli. A total of 64,372,921 clean reads were obtained and 39,057 differentially expressed genes (DEGs) were identified. In the Bb vs. PBS group (PBS as the control), 9,092 genes were up-regulated and 4,438 genes were down-regulated; in the ML vs. PBS group, 5,903 genes were up-regulated and 5,175 genes were down-regulated. The KEGG (Kyoto Encyclopedia of Genes and Genomes) and GO (Gene Ontology) analyses of DEGs confirmed that many DEGs were associated with "Metabolism pathway", "cellular process", "cell" and "catalytic activity". Among them, 194 and 149 differentially expressed genes were related to immunity in the Bb vs. PBS group and ML vs. PBS group, respectively. We verified the reliability of the data with reverse transcription quantitative real-time PCR analysis of randomly selected genes. Furthermore, the phylogenetic tree results showed that HSP90, PGRP and MyD88 genes of A. selene were most closely related to Antheraea pernyi (Guérin-Méneville). These results will provide an overview of the molecular mechanism of A. selene resistance to fungal and bacterial infections as well as an evolutionary aspect of these genes. Moreover, the interrelated trophic mechanisms among different groups of organisms are vital to explore, thus this study will lay a foundation for further studies on the innate immune mechanism of saturniid moths, and provide important theoretical basis for studying the relationship between A. selene and other species.


Assuntos
Beauveria , RNA , Transcriptoma , Animais , Beauveria/genética , Micrococcus luteus , Filogenia , Reprodutibilidade dos Testes
16.
Nanoscale ; 11(39): 18329-18337, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31573590

RESUMO

The sustainable production of H2 fuel via the hydrogen evolution reaction (HER) using low-cost catalysts to replace expensive noble metals is highly desired. Here using first-principles calculations, we design a delicate monolayer transition metal compound, Ni-MoS2, consisting of orderly interlaced Ni and Mo metal ions, and investigate its HER catalytic performance. The Gibbs free energy, ΔGH, which is the best descriptor for the HER, is calculated and optimized with respect to strain and S vacancies. Remarkably, the calculated ΔGH is found to be ∼0 eV at the biaxial strain of 11%-12%, which is superior to MoS2, for which straining alone is insufficient to achieve the optimal performance. We further reveal that along with straining, the bandgap is reduced and a semiconductor-to-metal transition is induced, leading to an enhancement in the charge transfer and HER performance. Moreover, ΔGH ≈ 0 eV is achieved at the S vacancy concentration of only ∼2.5%, which is in strong contrast to ∼12.5% required for MoS2. We further show that the defective Ni-MoS2 is able to enhance the conductivity, which leads to the reduction of ΔGH. Two remarkable HER mechanisms and alkaline HER kinetics have been demonstrated in this study: perfect Ni-MoS2 prefers the Volmer-Heyrovsky mechanism in the strain state, whereas the Volmer-Tafel mechanism is more preferred for the defective Ni-MoS2. The kinetic energy barrier of the alkaline HER is reduced, revealing that Ni-MoS2 promotes the rate-determining water dissociation step. The present work suggests that the designed monolayer Ni-MoS2 compound significantly outperforms MoS2 in terms of HER activity, and thus is promising for low-cost, pH-universal and high-performance HER applications.

18.
Biol Reprod ; 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31621839

RESUMO

Heritable mitochondrial DNA (mtDNA) mutations are common, yet only a few recurring pathogenic mtDNA variants account for the majority of known familial cases in humans. Purifying selection in the female germline is thought to be responsible for the elimination of most harmful mtDNA mutations during oogenesis. Here, we show that deleterious mtDNA mutations are abundant in ovulated mature mouse oocytes and preimplantation embryos recovered from PolG mutator females but not in their live offspring. This implies that purifying selection acts not in the maternal germline per se, but during post-implantation development. We further show that oocyte mtDNA mutations can be captured and stably maintained in embryonic stem cells (ESCs) and then reintroduced into chimeras, thereby allowing examination of the effects of specific mutations on fetal and postnatal development.

19.
Int J Biochem Cell Biol ; 116: 105613, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31539631

RESUMO

Renal tubular epithelial-mesenchymal transition (EMT) is the main pathological change in diabetic renal tubulointerstitial fibrosis. Mounting evidence indicates that the inhibitor of differentiation 2 (Id2) protein acts as a negative regulatory factor in organ fibrosis and can inhibit or reverse the process of fibrosis. However, its specific regulatory mechanism is not clear. Diabetes mellitus (DM) rat models were established by injecting rats with streptozotocin and sacrificing them after 16 weeks. Rat renal tubular epithelial cells (NRK-52E) were cultured with normal and high glucose. Immunohistochemical analysis, double immunofluorescence staining, co-immunoprecipitation, Western blot analysis, and real-time polymerase chain reaction were used to determine the expression of Id2, Twist, Smad1/5/8, E-cadherin, α-smooth muscle actin (α-SMA), and collagen Ⅳ. The results showed that bone morphogenetic protein-7 (BMP-7) upregulated the expression of Id2 against high-glucose-induced EMT and extracellular matrix secretion. Moreover, only the simultaneous knockdown of Smad1, Smad5, and Smad8 downregulated the expression of Id2, which was not altered by the individual knockdown of Smad1, Smad5, and Smad8. Basic helix-loop-helix (bHLH) transcription factors were essential for Id2 to regulate the role of downstream target genes, and Twist was a bHLH transcription factor. Therefore, the expression of Twist was examined in this study. Twist was found to be highly expressed in the kidney of DM rats and renal tubular epithelial cells cultured with high glucose. The overexpression of Id2 did not alter the expression of Twist, but the interaction between Id2 and Twist was enhanced. In conclusion, the data showed the specific mechanism underlying Id2 negative regulation in diabetic renal tubulointerstitial fibrosis.

20.
Biochem Pharmacol ; 170: 113645, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31545975

RESUMO

Autoimmune uveitis (AU), a sight-threatening intraocular disorder, is still a challenge for ophthalmologists in clinic. Teriflunomide has been approved for multiple sclerosis (MS) in 2012 for its immunoregulatory function. However, the effect and mechanisms of teriflunomide in uveitis are still unknown. In this investigation, we used a murine model of non-infectious uveitis, experimental autoimmune uveitis (EAU), to explore the anti-inflammatory features of teriflunomide. Treatment with teriflunomide resulted in reduced clinical and pathological scores of retinal inflammations, accompanied by decreased intraocular infiltration of Th17 and Th1 cells in EAU mice. Meanwhile, teriflunomide treatment inhibited the proliferation and polarization of CD4+ T cells to Th17 and Th1 cells. Moreover, adoptive transfer of teriflunomide primed IRBP1-20-T cells failed to induce EAU. Interestingly, we found that teriflunomide suppressed the maturation and function of dendritic cells (DCs) both in vivo and in vitro. In conclusion, our findings suggest that teriflunomide alleviates inflammation in EAU mice by down-regulating Th17 and Th1 cells and suppresses the maturation and function of DCs for the first time.

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