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1.
Artigo em Inglês | MEDLINE | ID: mdl-34757695

RESUMO

Condensation of DNA helices into hexagonally packed bundles and toroids represents an intriguing example of functional organization of biological macromolecules at the nanoscale. The condensation models are based on the unique polyelectrolyte features of DNA, however here we could reproduce a DNA-like condensation with supramolecular helices of small chiral molecules, thereby demonstrating that it is a more general phenomenon. We show that bile salt sodium deoxycholate can form supramolecular helices upon interaction with oppositely charged polyelectrolytes of homopolymer or block copolymers. At higher order, a controlled hexagonal packing of the helices into DNA-like bundles and toroids could be accomplished. The results disclose unknown similarities between covalent and supramolecular non-covalent helical polyelectrolytes, which inspire visionary ideas of constructing supramolecular versions of biological macromolecules. As drug nanocarriers the polymer-BS superstructures would get advantage of a complex chirality at molecular and supramolecular levels, whose effect on the nanocarrier assisted drug efficiency is a still unexplored fascinating issue.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34791775

RESUMO

Microbial infections has become a great threat to human health and one of the main risks arises from direct contact with the surfaces contaminated by pathogenic microbes. Developing long-lasting antimicrobial materials becomes an urgent need. Herein, a kind of hexagonal column interpenetrated spheres (HCISs) are fabricated by non-covalent assembly of plant gallic acid with quaternary ammonium surfactants. Different from one-time burst release of conventional antimicrobial agents, the HCIS acts like a "antimicrobial molecular bank" and releases the antimicrobial ingredients in a multistage way, leading to long-lasting antimicrobial performance. Taking advantage of strong hydrophobicity and adhesion, HCISs are applicable to various substrates and endowed with anti-water washing property, thus showing high in vitro antimicrobial efficiency ( > 99 %) even after being used for 10 cycles. Meanwhile, HCISs exhibit broad-spectrum antimicrobial activity against bacteria and fungi, and have good biocompatibility with mammalian cells. Such a low-cost and portable long-lasting antimicrobial agent meets the growing anti-infection demand in public spaces.

3.
Org Lett ; 23(22): 8761-8765, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34747180

RESUMO

The biochemical elucidation of the early biosynthetic pathways of miharamycins and amipurimycin revealed the roles of several enzymes, which include GMP hydrolase, represented by MihD/ApmD, and hypothetical proteins, MihI/ApmI, unexpectedly exhibiting the dual function of the guanylglucuronic acid assembly and GMP cleavage. In addition, MihE, a carbonyl reductase that functions on the C2 branch of high-carbon sugars, and MihF, a rare guanine O-methyltransferase, were also functionally verified.

4.
BMC Vet Res ; 17(1): 332, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663327

RESUMO

BACKGROUND: Captive wild animals in zoos infected with Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi, and Blastocystis sp. can be sources of zoonotic infections and diseases. Therefore, to investigate the distribution of these pathogens in captive wild animals of zoos in Henan, China, a total of 429 fresh fecal samples were collected from six zoos in Henan, China. The infection rates of Cryptosporidium spp., G. duodenalis, E. bieneusi, and Blastocystis sp. were determined by PCR analysis of corresponding loci. Positive results for Cryptosporidium (C. parvum and C. hominis) were subtyped based on the (gp60) gene. RESULTS: The overall prevalence was 43.1% (185/429), and the prevalence of Cryptosporidium, Giardia duodenalis, Enterocytozoon bieneusi, and Blastocystis sp. were 2.8% (12/429), 0.5% (2/429), 20.8% (89/429), and 19.1% (82/429), respectively. Five Cryptosporidium species, namely, C. hominis, C. parvum, C. muris, C. andersoni, and C. macropodum, were identified in this study. Cryptosporidium parvum was further subtyped as IIdA19G1. Two Giardia duodenalis assemblages (A and E) were also identified. A total of 20 Enterocytozoon bieneusi genotypes were detected, including 18 known (BEB6, D, HND-1, CD7, SDD1, Henan-IV, KIN-1, CHK1, Peru8, Henan-V, CHG11, CHG-1, CHS9, CHG21, Type-IV, CHC9, CM5, and CHB1) and 2 novel genotypes (CHWD1 and CHPM1). A total of nine subtypes of Blastocystis sp. (ST1, ST2, ST3, ST5, ST6, ST7, ST10, ST13, and ST14) were identified in captive wild animals in zoos in the present study. Cryptosporidium andersoni, nine Enterocytozoon bieneusi genotypes, and five Blastocystis subtypes were here first identified in new hosts. CONCLUSIONS: Our study has expanded the host ranges of these four pathogens. The data indicate that animals in zoos can commonly be infected with these four zoonotic pathogens, and animals in zoos are potential sources of zoonotic infections in humans.


Assuntos
Animais de Zoológico , Blastocystis/isolamento & purificação , Cryptosporidium/isolamento & purificação , Enterocytozoon/isolamento & purificação , Giardia lamblia/isolamento & purificação , Doenças Parasitárias em Animais/parasitologia , Animais , Blastocystis/genética , China/epidemiologia , Cryptosporidium/classificação , Cryptosporidium/genética , Enterocytozoon/genética , Genótipo , Giardia lamblia/genética , Especificidade de Hospedeiro , Doenças Parasitárias em Animais/epidemiologia , Prevalência
5.
Oxid Med Cell Longev ; 2021: 5147069, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630849

RESUMO

Intestinal ischemia-reperfusion (I/R) may induce cell/tissue injuries, leading to multiple organ failure. Based on our preexperiments, we proposed that sesamin could protect against and ameliorate intestinal I/R injuries and related disorders with involvement of activating Nrf2 signaling pathway. This proposal was evaluated using SD intestinal I/R injury rats in vivo and hypoxia/reoxygenation- (H/R-) injured rat small intestinal crypt epithelial cell line (IEC-6 cells) in vitro. Sesamin significantly alleviated I/R-induced intestinal histopathological injuries and significantly reduced serum biochemical indicators ALT and AST, alleviating I/R-induced intestinal injury in rats. Sesamin also significantly reversed I/R-increased TNF-α, IL-6, IL-1ß, and MPO activity in serum and MDA in tissues and I/R-decreased GSH in tissues and SOD in both tissues and IEC-6 cells, indicating its anti-inflammatory and antioxidative stress effects. Further, sesamin significantly decreased TUNEL-positive cells, downregulated the increased Bax and caspase-3 protein expression, upregulated the decreased protein expression of Bcl-2 in I/R-injured intestinal tissues, and significantly reversed H/R-reduced IEC-6 cell viability as well as reduced the number of apoptotic cells among H/R-injured IEC-6 cell, showing antiapoptotic effects. Activation of Nrf2 is known to ameliorate tissue/cell injuries. Consistent with sesamin-induced ameliorations of both intestinal I/R injuries and H/R injuries, transfection of Nrf2 cDNA significantly upregulated the expression of Nrf2, HO-1, and NQO1, respectively. On the contrary, either Nrf2 inhibitor (ML385) or Nrf2 siRNA transfection significantly decreased the expression of these proteins. Our results suggest that activation of the Nrf2/HO-1/NQO1 signaling pathway is involved in sesamin-induced anti-inflammatory, antioxidative, and antiapoptotic effects in protection against and amelioration of intestinal I/R injuries.

6.
Environ Monit Assess ; 193(11): 706, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34623532

RESUMO

This study aimed to research the effects of forest (Pinus elliottii, slash pine) and shrub (Vitex trifolia) plantation on the soil microbial community in sandification land by using the Illumina Miseq sequencing of 16S rRNA and ITS rRNA genes and combined with the soil properties analysis to explore the driving factors. Finally, the results showed that the dominant bacterial phyla were Chloroflexi, Actinobacteria, Proteobacteria, and Acidobacteria; the shrub and forest plantation significantly increasing the proportion of Acidobacteria, while decreasing the proportion of Proteobacteria. For the fungal community, forest plantation was significantly changing the community structure at the phylum level that shifted from Ascomycota to Basidiomycota, and the ectomycorrhizal fungi take the most abundant with genus Rhizopogon predominant. The soil bacterial Chao1 and Shannon indices were significantly increased after revegetation, while the soil fungal Shannon diversity in the forest land that significantly correlated with soil total organic carbon and C/N was lower than that in the sandy and shrub land (p < 0.05). Besides, the bacterial and fungal communities were significantly affected by soil water content among all analyzed soil properties. Our results suggest that the revegetation significantly increasing the soil bacterial diversity that correlated with soil water content, total organic carbon, and available phosphorus, but there was no significant change in community structure. In contrast, slash pine plantation changes the fungal community structure and diversity dramatically. This change and possible succession of fungal community with stand age increasing may lead to the fragility of the plantation, which deserves continuous attention.


Assuntos
Micobioma , Solo , China , Monitoramento Ambiental , RNA Ribossômico 16S , Microbiologia do Solo
7.
Redox Biol ; 47: 102156, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34607159

RESUMO

OBJECTIVE: The disruption of mitochondrial redox homeostasis in endothelial cells (ECs) can cause chronic inflammation, a substantial contributor to the development of atherosclerosis. Chronic sympathetic hyperactivity can enhance oxidative stress to induce endothelial dysfunction. We determined if renal denervation (RDN), the strategy reducing sympathetic tone, can protect ECs by ameliorating mitochondrial reactive oxygen species (ROS)-induced inflammation to reduce atherosclerosis. METHODS AND RESULTS: ApoE deficient (ApoE-/-) mice were conducted RDN or sham operation before 20-week high-fat diet feeding. Atherosclerosis, EC phenotype and mitochondrial morphology were determined. In vitro, human arterial ECs were treated with norepinephrine to determine the mechanisms for RDN-inhibited endothelial inflammation. RDN reduced atherosclerosis, EC mitochondrial oxidative stress and inflammation. Mechanistically, the chronic sympathetic hyperactivity increased circulating norepinephrine and mitochondrial monoamine oxidase A (MAO-A) activity. MAO-A activation-impaired mitochondrial homeostasis resulted in ROS accumulation and NF-κB activation, thereby enhancing expression of atherogenic and proinflammatory molecules in ECs. It also suppressed mitochondrial function regulator PGC-1α, with involvement of NF-κB and oxidative stress. Inactivation of MAO-A by RDN disrupted the positive-feedback regulation between mitochondrial dysfunction and inflammation, thereby inhibiting EC atheroprone phenotypic alterations and atherosclerosis. CONCLUSIONS: The interplay between MAO-A-induced mitochondrial oxidative stress and inflammation in ECs is a key driver in atherogenesis, and it can be reduced by RDN.

8.
World Neurosurg ; 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34648989

RESUMO

OBJECTIVE: To develop and validate a nomogram for predicting the risk of venous thromboembolism in critically ill patients with primary intracerebral hemorrhage. METHODS: Patients ≥18 years old with primary intracerebral hemorrhage were screened within 24 hours of onset from January 2019 to April 2021. Univariate and multivariate logistic regression analyses were performed to screen out independent predictors that were significantly associated with venous thromboembolism. A nomogram was constructed based on the results of a multivariate regression analysis. Discrimination and calibration were used to evaluate performance of the nomogram. A decision curve analysis was used to assess its clinical utility. RESULTS: This study enrolled 369 patients. The nomogram included 3 predictors from the regression analysis: D-dimer, National Institutes of Health Stroke Scale score, and Glasgow Coma Scale score on admission. The area under the receiver operating characteristic curve was 0.794, indicating good discrimination of the nomogram. The nomogram demonstrated calibration curves with slight deviation from the ideal predictions. Decision curve analysis showed that the prediction nomogram was clinically useful. CONCLUSIONS: This nomogram comprising D-dimer, National Institutes of Health Stroke Scale score and Glasgow Coma Scale score on admission can accurately predict the risk of venous thromboembolism in critically ill patients with intracerebral hemorrhage.

9.
Eur J Med Chem ; 227: 113933, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34689072

RESUMO

The P2Y14 nucleotide receptor, a subtype of P2Y receptors, is implicated in many human inflammatory diseases. Based on the identification of favorable residues of two screening hits in the almost symmetrical P2Y14 binding domain, we describe the structural optimization of previously identified virtual screening hits 6 and 7 that result in the development of P2Y14R antagonists with a novel 2-phenyl-benzoxazole acetamide chemical scaffold. Notably, compound 52 showed potent P2Y14R antagonistic activity (IC50 = 2 nM), and a stronger inhibitory effect on MSU-induced inflammatory in vitro, better than a previously described P2Y14R antagonist PPTN. In vivo evaluation demonstrated that compound 52 also had satisfactory inhibitory activity on the inflammatory response of gout flares in mice. Moreover, P2Y14R antagonist 52 decreased paw swelling and inflammatory cell infiltration through cAMP/NLRP3/GSDMD signaling pathways in MSU-induced acute gouty arthritis mice. The discussions on the binding mechanism that employ MM/GBSA free energy calculations/decompositions also provide some useful clues for further structural designing of compound 52. Taken together, 2-phenyl-benzoxazole acetamide derivative 52 with potent P2Y14R antagonistic activity and in vivo potency could be a promising strategy for gout therapy and deserves further optimization.

10.
Soft Matter ; 17(44): 10080-10089, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34714904

RESUMO

The hydration of amino acids closely correlates the hydration of peptides and proteins and is critical to their biological functions. However, complete and quantitative understanding about the hydration of amino acids is lacking. Here, tightly and loosely bound water of 20 zwitterionic amino acids are quantitatively distinguished and determined by Raman spectroscopy with multivariate curve resolution (Raman-MCR) and differential scanning calorimetry (DSC). The total hydration water obtained from Raman-MCR and the tightly bound water determined by DSC have certain relevance, but they do not exactly correspond. In particular, Pro, Arg and Lys exhibit larger number of tightly bound water molecules (4.02-6.59), showing a significant influence on the onset transition temperature and the melting enthalpy values of water molecules, which provides direct evidence for their unique functions associated with biological water. Asn, Ser, Thr, Met, His and Glu have a smaller number of tightly bound water molecules (0.30-1.31), whilst the other remaining 11 amino acids only contain loosely bound water molecules. Four exceptional amino acids Ile, Leu, Phe and Val show fewer tightly bound water molecules but a higher number of loosely bound water molecules. As for the hydration shell structure, most amino acids except Pro and Trp enhance tetrahedral water structure and H-bonds relative to pure water and at least 1.9% of the hydration water molecules associated with the amino acids show non-hydrogen-bonded OH defects. This work combines two effective experimental techniques to reveal the hydration water structure and quantitatively analyze two kinds of bound water molecules of 20 amino acids.


Assuntos
Aminoácidos , Água , Sequência de Aminoácidos , Fragmentos de Peptídeos , Tripsina
11.
Sensors (Basel) ; 21(20)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34695986

RESUMO

Automatic defect detection of tire has become an essential issue in the tire industry. However, it is challenging to inspect the inner structure of tire by surface detection. Therefore, an X-ray image sensor is used for tire defect inspection. At present, detection of defective tires is inefficient because tire factories commonly conduct detection by manually checking X-ray images. With the development of deep learning, supervised learning has been introduced to replace human resources. However, in actual industrial scenes, defective samples are rare in comparison to defect-free samples. The quantity of defective samples is insufficient for supervised models to extract features and identify nonconforming products from qualified ones. To address these problems, we propose an unsupervised approach, using no labeled defect samples for training. Moreover, we introduce an augmented reconstruction method and a self-supervised training strategy. The approach is based on the idea of reconstruction. In the training phase, only defect-free samples are used for training the model and updating memory items in the memory module, so the reproduced images in the test phase are bound to resemble defect-free images. The reconstruction residual is utilized to detect defects. The introduction of self-supervised training strategy further strengthens the reconstruction residual to improve detection performance. The proposed method is experimentally proved to be effective. The Area Under Curve (AUC) on a tire X-ray dataset reaches 0.873, so the proposed method is promising for application.


Assuntos
Aprendizado de Máquina não Supervisionado , Humanos , Radiografia , Raios X
12.
Front Cell Dev Biol ; 9: 720383, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692679

RESUMO

Hearing loss is a serious illness affecting people's normal life enormously. The acoustic properties of a tympanic membrane play an important role in hearing, and highly depend on its geometry, composition, microstructure and connection to the surrounding annulus. While the conical geometry of the tympanic membrane is critical to the sound propagation in the auditory system, it presents significant challenges to the study of the 3D microstructure of the tympanic membrane using traditional 2D imaging techniques. To date, most of our knowledge about the 3D microstructure and composition of tympanic membranes is built from 2D microscopic studies, which precludes an accurate understanding of the 3D microstructure, acoustic behaviors and biology of the tissue. Although the tympanic membrane has been reported to contain elastic fibers, the morphological characteristic of the elastic fibers and the spatial arrangement of the elastic fibers with the predominant collagen fibers have not been shown in images. We have developed a 3D imaging technique for the three-dimensional examination of the microstructure of the full thickness of the tympanic membranes in mice without requiring tissue dehydration and stain. We have also used this imaging technique to study the 3D arrangement of the collagen and elastic fibrillar network with the capillaries and cells in the pars tensa-annulus unit at a status close to the native. The most striking findings in the study are the discovery of the 3D form of the elastic and collagen network, and the close spatial relationships between the elastic fibers and the elongated fibroblasts in the tympanic membranes. The 3D imaging technique has enabled to show the 3D waveform contour of the collagen and elastic scaffold in the conical tympanic membrane. Given the close relationship among the acoustic properties, composition, 3D microstructure and geometry of tympanic membranes, the findings may advance the understanding of the structure-acoustic functionality of the tympanic membrane. The knowledge will also be very helpful in the development of advanced cellular therapeutic technologies and 3D printing techniques to restore damaged tympanic membranes to a status close to the native.

13.
Phys Rev Lett ; 127(14): 147202, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34652212

RESUMO

Exotic high-rank multipolar order parameters have been found to be unexpectedly active in more and more correlated materials in recent years. Such multipoles are usually dubbed "hidden orders" since they are insensitive to common experimental probes. Theoretically, it is also difficult to predict multipolar orders via ab initio calculations in real materials. Here, we present an efficient method to predict possible multipoles in materials based on linear response theory under random phase approximation. Using this method, we successfully predict two pure metastable magnetic octupolar states in monolayer α-RuCl_{3}, which is confirmed by self-consistent unrestricted Hartree-Fock calculations. We then demonstrate that these octupolar states can be stabilized in monolayer α-RuI_{3}, one of which becomes the octupolar ground state. Furthermore, we also predict a fingerprint of an orthogonal magnetization pattern produced by the octupole moment that can be easily detected by experiment. The method and the example presented in this Letter serve as a guide for searching multipolar order parameters in other correlated materials.

14.
Genomics ; 113(6): 3804-3810, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34534648

RESUMO

Long interspersed nuclear elements (LINEs) are retrotransposons that contribute to genetic variation in the human genome. LINE-1 elements in larger-scale studies are challenging to identify using sequencing technologies due to cost and scalability. We developed an approach using optical mapping for detection of full-length LINE-1 insertions and 10× sequencing for confirmation. We found 51 true positive full-length LINE-1 insertions, of which 4 are novel insertions, in NA12878. Repeating our analysis on a larger sample set representing 26 populations, we identified 329 full-length LINE-1 elements, of which 123 are novel. 24.8% of these 329 LINE-1 insertions were shared amongst all 5 superpopulations (AFR, AMR, EUR, EAS, SAS). The African superpopulation has a higher percentage of population-specific LINE-1 insertions than any other superpopulation. These data indicate that our approach can provide high-speed, cost-effective, and increased accuracy for LINE-1 detection. These data also provide an insight into variations of LINE-1 elements between different populations.

15.
Int J Biol Macromol ; 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34509522

RESUMO

Hair loss remains a challenging clinical problem that influences the quality of life. Three-dimensional (3D) bioprinting has become a valuable tool for fabricating tissue constructs for transplantation and other biomedical applications. Although some simple organs, such as skin and cartilage, have been successfully simulated, it remains challenging to make hair follicles (HFs), which are highly complex organs. The tissue engineering of human HFs has been a long-standing challenge, and progress with this has lagged behind that with other lab-grown tissues. This is principally due to a lack of availability of a platform that can successfully recapitulate the microenvironmental cues required to maintain the requisite cellular interactions for hair neogenesis. In this study, we used a 3D bioprinting technique based on a gelatin/alginate hydrogel to construct a multilayer composite scaffold with cuticular and corium layers to simulate the microenvironment of dermal papilla cells (DPCs) in the human body. This new approach permits the controllable formation of self-aggregating spheroids of DPCs in a physiologically relevant extracellular matrix and the initiation of epidermal-mesenchymal interactions, which results in HF formation in vivo. In conclusion, our 3D-bioprinted multilayer composite scaffold prepared using a gelatin/alginate hydrogel provides a suitable 3D microenvironment for DPCs to induce HF formation. The ability to regenerate entire HFs should have a significant impact on the medical management of hair loss. This method may also have critical applications for skin tissue engineering, with its appendages, for other purposes.

16.
JACS Au ; 1(4): 396-408, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-34467303

RESUMO

Industrial low-temperature methane combustion catalyst Pd/Al2O3 suffers from H2O-induced deactivation. It is imperative to design Pd catalysts free from this deactivation and with high atomic efficiency. Using a small-pore zeolite SSZ-13 as support, herein we report well-defined Pd catalysts with dominant active species as finely dispersed Pd cations, uniform PdO particles embedded inside the zeolite framework, or PdO particles decorating the zeolite external surface. Through detailed reaction kinetics and spectroscopic and microscopic studies, we show that finely dispersed sites are much less active than PdO nanoparticles. We further demonstrate that H2O-induced deactivation can be readily circumvented by using zeolite supports with high Si/Al ratios. Finally, we provide a few rational catalyst design suggestions for methane oxidation based on the new knowledge learned in this study.

17.
Nanoscale ; 13(37): 15937-15951, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34523658

RESUMO

Vascular dysfunction and bacterial infection are key factors for the non-healing of diabetic ulcers. Growth factors and antibiotics seem to effectively target both issues. However, the short half-life and high cost of growth factors and the antibiotics resistance of bacteria greatly limit their further widespread applications. Novel strategies or agents with both angiogenic and antibacterial activities are urgently desirable. Copper peroxide (CuO2) nanodots were reported to be decomposed into Cu2+ and H2O2 under mild acid conditions (pH 5.5). Considering that both decomposed products are acknowledged antibacterial agents (Cu2+, H2O2) and angiogenesis activator (Cu2+), we believe that CuO2 nanodots are suitable for diabetic ulcer treatment because the pathological environment of infected chronic wounds is mildly acidic with pH 5.5-5.6. As expected, in vitro experiments showed that CuO2 nanodots possessed excellent bactericidal properties against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and even methicillin-resistant Staphylococcus aureus (MRSA). CuO2 nanodots induced the high expression of hypoxia-inducible factor (HIF-1α) and vascular endothelial growth factor (VEGF) in human umbilical vein endothelial cells (HUVECs), subsequently promoting the cell migration and tube formation for angiogenesis. In particular, CuO2 nanodots exhibited good dispersibility and sprayable behavior in water. In vivo experiments demonstrated that the spayed CuO2 nanodots in the wound area could effectively combat MRSA, reduce inflammation, promote angiogenesis, and consequently accelerate wound healing. Moreover, the sprayed CuO2 nanodots in the wound sites caused negligible system toxicity. This study provides proof-of-principle evidence for applying the sprayed CuO2 nanodots for infected diabetic ulcer treatment.


Assuntos
Diabetes Mellitus , Staphylococcus aureus Resistente à Meticilina , Antibacterianos/farmacologia , Bactérias , Cobre , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio , Peróxidos , Úlcera , Fator A de Crescimento do Endotélio Vascular , Cicatrização
18.
Integr Zool ; 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34496458

RESUMO

The transfer of mitochondrial DNA to the nuclear genome gives rise to the nuclear DNA sequences of mitochondrial origin (NUMTs), considered as a driving force in genome evolution. In this study, NUMTs in 23 bat genomes were investigated and compared systematically. The results showed that NUMTs existed in 22 genomes except for Noctilio leporinus, suggesting that mitochondrial fragment insertion in the nuclear genome was a common event in bat genomes. However, remarkable variations in NUMTs number, cumulative length, and proportion in the nuclear genome were discovered across bat species. Further orthologous NUMT loci analysis of the Phyllostomidae family indicated that the NUMTs insertion events in bat genomes were homoplasy-free. The NUMTs were mainly inserted into the intergenic regions, particularly, co-localized with repetitive sequences (especially transposable elements). However, several NUMTs were inserted into genes, some of which were in the exon region of functional genes. One NUMT in the genome of Pteropus alecto surprisingly matched with cDNA of ATP8B3 that provided evidence of NUMTs with coding function. Phylogenic analysis on NUMTs originating from COXI and COXII loci highlighted 2 clusters of Yinpterochiroptera and Yangochiroptera for Chiroptera. Seven NUMTs from Rhinolophus ferrumequinum were amplified, and the sequencing results confirmed the reliability of the NUMT analysis. One of them was polymorphic for the presence or absence of the NUMT insertion, and each genotype of NUMT loci showed a distinct regional distribution pattern. The information obtained in this study provides novel insights into the NUMT organization and features in bat genomes and establishes a basis for further studying of the evolution of bat species.

19.
Int J Mol Med ; 48(5)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34498713

RESUMO

Investigating the factors that influence the inflammatory response of microglial cells is crucial for understanding the pathogenesis of cryptococcal meningitis (CM). MicroRNAs (miRNAs/miRs) play an important role in inducing host defenses and activating the immune response during microbial infection; however, the regulatory mechanisms of miRNAs in cryptococcal meningitis remain poorly defined. In a previous study, the authors assessed the miRNA profiles of THP­1 (human acute monocytic leukemia cells) cells following Cryptococcus neoformans (C. neoformans) infection. In the present study, it was found that miR­4792 expression was downregulated in BV2 cells infected with C. neoformans, whilst that of its target gene, epidermal growth factor receptor (EGFR), was upregulated. Infected cells in which miR­4792 was overexpressed exhibited a decreased EGFR transcript expression, reduced mitogen­activated protein kinase (MAPK) signaling and a decreased secretion of inflammatory cytokines. In addition, following antifungal treatment in patients with cryptococcal meningitis, the levels of miR­4792 in the cerebrospinal fluid significantly increased, whilst the expression of EGFR significantly decreased. In addition, receiver operator characteristic analysis revealed miR­4792 (AUCROC=0.75) and EGFR (AUCROC=0.79) as potential diagnostic markers in patients with cryptococcal meningitis.

20.
IEEE Trans Image Process ; 30: 7511-7526, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34460374

RESUMO

Because of the increasing ease of video capture, many millions of consumers create and upload large volumes of User-Generated-Content (UGC) videos to social and streaming media sites over the Internet. UGC videos are commonly captured by naive users having limited skills and imperfect techniques, and tend to be afflicted by mixtures of highly diverse in-capture distortions. These UGC videos are then often uploaded for sharing onto cloud servers, where they are further compressed for storage and transmission. Our paper tackles the highly practical problem of predicting the quality of compressed videos (perhaps during the process of compression, to help guide it), with only (possibly severely) distorted UGC videos as references. To address this problem, we have developed a novel Video Quality Assessment (VQA) framework that we call 1stepVQA (to distinguish it from two-step methods that we discuss). 1stepVQA overcomes limitations of Full-Reference, Reduced-Reference and No-Reference VQA models by exploiting the statistical regularities of both natural videos and distorted videos. We also describe a new dedicated video database, which was created by applying a realistic VMAF-Guided perceptual rate distortion optimization (RDO) criterion to create realistically compressed versions of UGC source videos, which typically have pre-existing distortions. We show that 1stepVQA is able to more accurately predict the quality of compressed videos, given imperfect reference videos, and outperforms other VQA models in this scenario.

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