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1.
Chemosphere ; 286(Pt 1): 131603, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34325259

RESUMO

A promising technology was developed for the remediation of fluoranthene (FLT) contaminated water and soil. Specifically, iron nanoparticles supported on N-doped carbon foam (Fe@CF-N) was synthesized by in-situ impregnation and a unique calcination process using pine cone as the precursor. The obtained Fe@CF-N was used as an activator of potassium peroxymonosulfate (PMS) to degrade FLT in water and soil. According to experimental results, Fe@CF-N had a three-dimensional network structure with a large specific surface area of 249.0 m2 g-1, displaying excellent catalytic performance. The maximum removal efficiency of FLT in water and soil reached 81.83% and 78.12% within 180 min, respectively. After four consecutive degradation cycles, the removal efficiency of FLT in water was still 55%. Electron spin resonance (ESR) measurements showed that hydroxyl radicals (·OH), sulfate radical (SO4-·) and 1O2 were the major reactive oxygen species (ROS). A series of low molecular weight intermediates were generated during the FLT degradation progress, such as C6H6O3 and C3H8O2. The effect of Fe@CF-N/PMS system on the phytotoxicity was evaluated via bioassay based on peas. The results indicated that seed germination rate and root shoot elongation of remediated soil by Fe@CF-N/PMS system were not significantly different from those of noncontaminated soil. This study provided a cost-effective remediation option for PAHs contaminated water and soil.


Assuntos
Ferro , Nanopartículas , Carbono , Fluorenos , Peróxidos , Solo , Água
2.
Front Mol Biosci ; 8: 675993, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34738011

RESUMO

Mdfi, an inhibitor of myogenic regulatory factors, is involved in myoblast myogenic development and muscle fiber type transformation. However, the regulatory network of Mdfi regulating myoblasts has not been revealed. In this study, we performed microRNAs (miRNAs)-seq on Mdfi overexpression (Mdfi-OE) and wild-type (WT) C2C12 cells to establish the regulatory networks. Comparative analyses of Mdfi-OE vs. WT identified 66 differentially expressed miRNAs (DEMs). Enrichment analysis of the target genes suggested that DEMs may be involved in myoblast differentiation and muscle fiber type transformation through MAPK, Wnt, PI3K-Akt, mTOR, and calcium signaling pathways. miRNA-mRNA interaction networks were suggested along with ten hub miRNAs and five hub genes. We also identified eight hub miRNAs and eleven hub genes in the networks of muscle fiber type transformation. Hub miRNAs mainly play key regulatory roles in muscle fiber type transformation through the PI3K-Akt, MAPK, cAMP, and calcium signaling pathways. Particularly, the three hub miRNAs (miR-335-3p, miR-494-3p, and miR-709) may be involved in both myogenic differentiation and muscle fiber type transformation. These hub miRNAs and genes might serve as candidate biomarkers for the treatment of muscle- and metabolic-related diseases.

3.
Anal Chem ; 93(47): 15703-15711, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34787995

RESUMO

Spectroscopic stimulated Raman scattering (SRS) imaging has become a useful tool finding a broad range of applications. Yet, wider adoption is hindered by the bulky and environmentally sensitive solid-state optical parametric oscillator (OPO) in a current SRS microscope. Moreover, chemically informative multiwindow SRS imaging across C-H, C-D, and fingerprint Raman regions is challenging due to the slow wavelength tuning speed of the solid-state OPO. In this work, we present a multiwindow SRS imaging system based on a compact and robust fiber laser with rapid and wide tuning capability. To address the relative intensity noise intrinsic to a fiber laser, we implemented autobalanced detection, which enhances the signal-to-noise ratio of stimulated Raman loss imaging by 23 times. We demonstrate high-quality SRS metabolic imaging of fungi, cancer cells, and Caenorhabditis elegans across the C-H, C-D, and fingerprint Raman windows. Our results showcase the potential of the compact multiwindow SRS system for a broad range of applications.

4.
Urol Oncol ; 39(12): 837.e19-837.e28, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34654644

RESUMO

AIM: This study aimed to evaluate the value of real-time contrast-enhanced ultrasound (CEUS) combined with contrast-enhanced computed tomography (CECT) in the differential diagnosis of clear cell renal cell carcinoma (CCRCC), papillary renal cell carcinoma (PRCC), and chromophobe renal cell carcinoma (CRCC). MATERIALS AND METHODS: In the present study, 82 patients with CCRCC, 24 patients with PRCC, and 19 patients with CRCC were confirmed by pathology of the resected tumor. All patients were evaluated by CEUS and CECT before the operation. In addition, the contrast enhancement mode of CEUS and CECT and the contrast parameters of the region of interest (ROI) time-intensity curve between the lesions and the surrounding normal renal parenchyma by CEUS were compared and analyzed. RESULTS: Compared with the pathological results, the diagnostic accuracy of ultrasound in the 3 groups was 87.8% (72/82), 83.3% (20/24) and 73.7% (14/19). There was no significant difference between CEUS and CECT in the diagnostic accuracy of all groups (P>0.05). Meanwhile, compared with the surrounding renal parenchyma by CEUS, 82.5% (66/80) of CCRCC lesions showed "fast-forward and fast/slow-retrograde," while 83.3% (20/24) of PRCC, and 84.2% (16/19) showed "slow-forward and fast/slow-retrograde." Significant differences in the enhancement modes of CEUS were found among the CCRCC, PRCC, and CRCC lesions (P < 0.05). And the enhancement modes could be quantitatively analyzed by the ROI time-intensity curve of the lesion. Moreover, lesions enhanced by CECT and 74.4% (61/82) of CCRCC lesions showed "fast-forward and fast/slow-retrograde," while 66.7% (16/24) of PRCC and 84.2% (16/19) of CRCC showed "slow-forward and fast/slow-retrograde." The contrast modes and enhancement uniformity of CEUS and CECT showed no significant differences among the CCRCC, PRCC, and CRCC lesions (P > 0.05). CONCLUSION: CEUS and quantitative analysis of ROI time-intensity curve can be used for differential diagnosis of the 3 RCC subtypes. The combination of CEUS and CECT can help us differentiate RCC subtypes and is of great significance for clinical treatment strategies and prognostication.

5.
Public Health Nutr ; : 1-12, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34615568

RESUMO

OBJECTIVE: The Democratic Republic of the Congo (DRC) has one of the highest levels of child undernutrition globally; however, little information exists on the underlying socio-economic inequalities resulting in undernutrition. This study aims to examine the differences in the nutritional statuses of children across different wealth quintiles and explores the association between malnutrition in children and related factors. DESIGN: We utilised the 2018 Multiple Indicator Cluster Survey data. We estimated the prevalence of malnutrition across all twenty-six provinces. The study used the WHO 2006 child growth standards to measure stunting, underweight and wasting. We employed a mixed-effect linear model to analyse the association between nutritional status and healthcare accessibility, domestic sanitation, and socio-demographic factors. SETTING: Twenty-six provinces in the DRC. PARTICIPANTS: 21 477 children under 5 years of age and 21 828 women of childbearing age in the DRC. RESULTS: The national prevalence of underweight, stunting and wasting was found to be 23·33 %, 42·05 % and 5·66 %, respectively. Household wealth and mother's education level were significantly positively associated with the nutritional statuses of children. Among households in the lowest wealth quintile, residence in urban areas was a protective factor against undernutrition. CONCLUSION: The findings of this study indicate considerable socio-economic inequalities in the nutritional statuses of children under 5 years of age in the DRC, highlighting the need for nutrition promotion as part of maternal and child healthcare. Interventions and policies should include improving nutrition education for less-educated mothers, in particular, in the central provinces of the DRC.

6.
Sci Total Environ ; 807(Pt 2): 150722, 2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34610400

RESUMO

Polyethylene glycol (PEG) precipitation is one of the conventional methods for virus concentration. This technique has been used to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in wastewater. The procedures and seeded surrogate viruses were different among implementers; thus, the reported whole process recovery efficiencies considerably varied among studies. The present study compared five PEG precipitation procedures, with different operational parameters, for the RT-qPCR-based whole process recovery efficiency of murine hepatitis virus (MHV), bacteriophage phi6, and pepper mild mottle virus (PMMoV), and molecular process recovery efficiency of murine norovirus using 34 raw wastewater samples collected in Japan. The five procedures yielded significantly different whole process recovery efficiency of MHV (0.070%-2.6%) and phi6 (0.071%-0.51%). The observed concentration of indigenous PMMoV ranged from 8.9 to 9.7 log (8.2 × 108 to 5.6 × 109) copies/L. Interestingly, PEG precipitation with 2-h incubation outperformed that with overnight incubation partially due to the difference in molecular process recovery efficiency. The recovery load of MHV exhibited a positive correlation (r = 0.70) with that of PMMoV, suggesting that PMMoV is the potential indicator of the recovery efficiency of SARS-CoV-2. In addition, we reviewed 13 published studies and found considerable variability between different studies in the whole process recovery efficiency of enveloped viruses by PEG precipitation. This was due to the differences in operational parameters and surrogate viruses as well as the differences in wastewater quality and bias in the measurement of the seeded load of surrogate viruses, resulting from the use of different analytes and RNA extraction methods. Overall, the operational parameters (e.g., incubation time and pretreatment) should be optimized for PEG precipitation. Co-quantification of PMMoV may allow for the normalization of SARS-CoV-2 RNA concentration by correcting for the differences in whole process recovery efficiency and fecal load among samples.

7.
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.

8.
J Med Chem ; 64(19): 14664-14701, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34550682

RESUMO

Secondary mutations of FLT3 have become the main mechanism of FLT3 inhibitor resistance that presents a significant clinical challenge. Herein, a series of pyrazole-3-amine derivatives were synthesized and optimized to overcome the common secondary resistance mutations of FLT3. The structure-activity relationship and molecular dynamics simulation studies illustrated that the ribose region of FLT3 could be occupied to help address the obstacle of secondary mutations. Among those derivatives, compound 67 exhibited potent and selective inhibitory activities against FLT3-ITD-positive acute myeloid leukemia (AML) cells and possessed equivalent potency against transformed BaF3 cells with a variety of secondary mutations. Besides, cellular mechanism assays demonstrated that 67 strongly inhibited phosphorylation of FLT3 and its downstream signaling factors, as well as induced cell cycle arrest and apoptosis in MV4-11 cells. In the MV4-11 xenograft models, 67 exhibited potent antitumor potency without obvious toxicity. Taken together, these results demonstrated that 67 might be a drug candidate for the treatment of FLT3-ITD-positive AML.

9.
Dalton Trans ; 50(40): 14390-14399, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34569558

RESUMO

The incorporation of active nitrogen species in carbon materials has been widely demonstrated as a viable means to produce superior lithium storage materials, while the precise regulation of nitrogen configurations as well as their content still remains a formidable challenge. Herein, nitrogen-free porous carbon frameworks were synthesized by a self-templating strategy from disodium citrate, and post-annealing yielded 10.4 at% N that was primarily pyrrolic-N and pyridinic-N with an atomic ratio of about 3 : 1, with negligible inactive graphitic-N. A gravimetric capacity of 570 mA h g-1 at a current density of 4 A g-1 was measured for a Li half-cell based on the as-prepared N-doped 3D carbon materials. Lithium-ion capacitors with this N-doped carbon as the anode and commercial AC as the cathode yielded energy densities of 58.9 and 142.6 W h kg-1 with the corresponding power densities of 7400 and 185 W kg-1, respectively. We suggest that the carbon materials with high content of pyrrolic-N and pyridinic-N especially pyrrolic-N have improved lithium storage.

10.
Chem Sci ; 12(33): 11056-11064, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34522303

RESUMO

A new rhodamine-like alkyne-substituted ligand (Rhodyne) was designed to coordinate a cyclometallated platinum(ii) system. The chemo-induced "ON-OFF" switching capabilities on the spirolactone ring of the Rhodyne ligand with an end-capping platinum(ii) metal centre can modulate the interesting acetylide-allenylidene resonance. The long-lived 3IL excited state of Rhodyne in its ON state as an optically active opened form was revealed via steady-state and time-resolved spectroscopy studies. Exceptional near-infrared (NIR) phosphorescence and delayed fluorescence based on a rhodamine-like structure were observed at room temperature for the first time. The position of the alkyne communication bridge attached to the platinum(ii) unit was found to vary the lead(ii)-ion binding mode and also the possible resonance structure for metal-mediated allenylidene formation. The formation of a proposed allenylidene resonance structure was suggested to rationalize these phenomena.

11.
Int J Mol Sci ; 22(18)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34575880

RESUMO

Escherichia coli and Staphylococcus aureus are two common pathogenic microorganisms that cause mastitis in dairy cows. They can cause clinical mastitis and subclinical mastitis. In recent studies, lncRNAs have been found to play an important role in the immune responses triggered by microbial inducers. However, the actions of lncRNAs in bovine mastitis remain unclear. The purpose of this study was to investigate the effects of bovine mammary epithelial cell injuries induced by treatment with E. coli and S. aureus, and to explore the lncRNA profile on cell injuries. The lncRNA transcriptome analysis showed a total of 2597 lncRNAs. There were 2234 lncRNAs differentially expressed in the E. coli group and 2334 in the S. aureus group. Moreover, we found that the E. coli and S. aureus groups of maternal genes targeted signaling pathways with similar functions according to KEGG and GO analyses. Two lncRNA-miRNA-mRNA interaction networks were constructed in order to predict the potential molecular mechanisms of regulation in the cell injuries. We believe that this is the first report demonstrating the dysregulation of lncRNAs in cells upon E. coli and S. aureus infections, suggesting that they have the potential to become important diagnostic markers and to provide novel insights into controlling and preventing mastitis.


Assuntos
Infecções por Escherichia coli/genética , Escherichia coli , Mastite Bovina/etiologia , Mastite Bovina/patologia , RNA Longo não Codificante/genética , Infecções Estafilocócicas/genética , Staphylococcus aureus , Animais , Bovinos , Biologia Computacional/métodos , Células Epiteliais/metabolismo , Escherichia coli/fisiologia , Infecções por Escherichia coli/microbiologia , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla/métodos , Interações Hospedeiro-Patógeno/genética , MicroRNAs/genética , Modelos Biológicos , Interferência de RNA , RNA Mensageiro/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/fisiologia
12.
J Inflamm Res ; 14: 3933-3943, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34429628

RESUMO

Purpose: It is well known that age is related to the incidence of Mycoplasma pneumoniae pneumonia (MPP), and how age and other factors contribute to MPP remains unclear. In this study, we investigate how age affects the prognosis of MPP. Patients and Methods: A total number of 1875 hospitalized children with pneumonia were enrolled in this study, including 52 children with refractory M. pneumoniae pneumonia (RMPP) and 298 children with non-RMPP. We used multiple logistic regression analysis to further identify the risk factors of RMPP, and found that age and polymorphonuclear neutrophils (PMNs) count were the key independent risk factors for the occurrence of RMPP. In order to improve specificity, 4.5 years old was taken as the cut-off value. Then, according to the cut-off value of age, 76 participants were recruited and divided into four groups: <4.5y MPP group, ≥4.5y MPP group, <4.5y health control (<4.5yHC) and ≥4.5y HC group. We explored the diverse functions of primary PMNs from children of different ages with MPP at cellular level. Besides, we studied the relationship between lung injury and PMNs in mice model with MPP of different ages. Results: We found that the age and PMNs count of RMPP group were significantly higher than those of the non-RMPP group. Importantly, there is a linear correlation between the age of patients with RMPP and the percentage of PMNs. Further analysis showed that elderly patients infected with M. pneumoniae had more active PMNs function. Meanwhile, proteomics showed that children with M. pneumoniae infection in different age groups have differences in PMNs apoptosis, nicotinamide adenine dinucleotide phosphate, mitochondrial function and oxidative stress. Finally, we found that age is also involved in the pathogenesis of mouse model with MPP. Conclusion: We speculate that age may contribute to the development of RMPP.

13.
Nephrology (Carlton) ; 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34431587

RESUMO

AIMS: In the general population, central arterial blood pressure has proved to be more closely related to left ventricular hypertrophy (LVH) than brachial arterial blood pressure. We aimed to investigate whether this relationship was true in patients with chronic kidney disease (CKD). METHODS: In this retrospective study, we reviewed the medical records of 289 adult patients with CKD from the Zhejiang Provincial People's Hospital in Zhejiang, China. Demographic, echocardiographic and brachial and central blood pressure parameters were retrieved from medical records. Central blood pressure was measured using the SphygmoCor® CvMS (AtCor, Australia) device and its corresponding software. Multivariate logistic regression analyses were performed to identify independent predictors of LVH. Receiver operating characteristic curves were used to determine the ability of central and brachial blood pressure to predict LVH. RESULTS: The left ventricular mass index was positively associated with both central and brachial blood pressures. However, multiple logistic regression analysis demonstrated that a central pulse pressure (CPP) ≥ 58 mm Hg was an independent risk factor for LVH (OR = 5.597, 95%CI 2.363-13.259, p < .001). Brachial pulse pressure is not superior to CPP in predicting LVH (area under the curve [AUC] = 0.695, 95%CI 0.634-0.756, p < .001 vs. AUC = 0.687, 95%CI: 0.626-0.748, p < .001, respectively; p = .4824). CONCLUSION: Our results suggested that, similarly to the general population, CPP is a better parameter for predicting the occurrence of LVH in patients with CKD.

14.
Nat Commun ; 12(1): 5033, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34413302

RESUMO

Characteristic properties of type III CRISPR-Cas systems include recognition of target RNA and the subsequent induction of a multifaceted immune response. This involves sequence-specific cleavage of the target RNA and production of cyclic oligoadenylate (cOA) molecules. Here we report that an exposed seed region at the 3' end of the crRNA is essential for target RNA binding and cleavage, whereas cOA production requires base pairing at the 5' end of the crRNA. Moreover, we uncover that the variation in the size and composition of type III complexes within a single host results in variable seed regions. This may prevent escape by invading genetic elements, while controlling cOA production tightly to prevent unnecessary damage to the host. Lastly, we use these findings to develop a new diagnostic tool, SCOPE, for the specific detection of SARS-CoV-2 from human nasal swab samples, revealing sensitivities in the atto-molar range.


Assuntos
Nucleotídeos de Adenina/química , COVID-19/diagnóstico , Proteínas Associadas a CRISPR/metabolismo , Sistemas CRISPR-Cas , Oligorribonucleotídeos/química , RNA Bacteriano/genética , Ribonucleases/metabolismo , SARS-CoV-2/genética , COVID-19/genética , COVID-19/metabolismo , COVID-19/virologia , Testes Diagnósticos de Rotina/métodos , Humanos , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/patogenicidade
15.
Light Sci Appl ; 10(1): 139, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226498

RESUMO

The realization of high-quality (Q) resonators regardless of the underpinning material platforms has been a ceaseless pursuit, because the high-Q resonators provide an extreme environment for confining light to enable observations of many nonlinear optical phenomenon with high efficiencies. Here, photonic microresonators with a mean Q factor of 6.75 × 106 were demonstrated on a 4H-silicon-carbide-on-insulator (4H-SiCOI) platform, as determined by a statistical analysis of tens of resonances. Using these devices, broadband frequency conversions, including second-, third-, and fourth-harmonic generations have been observed. Cascaded Raman lasing has also been demonstrated in our SiC microresonator for the first time, to the best of our knowledge. Meanwhile, by engineering the dispersion properties of the SiC microresonator, we have achieved broadband Kerr frequency combs covering from 1300 to 1700 nm. Our demonstration represents a significant milestone in the development of SiC photonic integrated devices.

16.
J Chem Phys ; 154(20): 204903, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34241152

RESUMO

Manipulating the ligand shell of semiconducting quantum dots (QDs) has proven to be a promising strategy to enhance their photocatalytic performance for small molecule transformations, such as H2 evolution and CO2 reduction. However, ligand-controlled catalysis for macromolecules, which differ from small molecules in penetrability and charge transfer behavior due to their bulky sizes, still remains undiscovered. Here, we systematically investigate the role of surface ligands in the photocatalytic performance of cadmium selenide (CdSe) QDs in light-induced atom transfer radical polymerization (ATRP) by using thiol-based ligands with various polarities and chain lengths. A highly enhanced polymerization efficiency was observed when 3-mercapto propionic acid (MPA), a short-chain and polar ligand, was used to modify the CdSe QDs' surface, achieving high chain-end fidelity, good temporal control, and a dispersity of 1.18, while also tolerating a wide-range of functional monomers ranging from acrylates to methacrylates and fluorinated monomers. Transient absorption spectroscopy and time-resolved photoluminescence studies reveal interesting mechanistic details of electron and hole transfers from the excited QDs to the initiators and 3-MPA capping ligands, respectively, providing key mechanistic insight of these ligand controlled and QD photocatalyzed ATRP processes. The thiolate ligands were found to serve as an efficient hole acceptor for QDs, which facilitates the formation of a charge-separated state, followed by electron transfer from the conduction band edge to initiators and ultimately suppressing charge recombination within the QD.

17.
Curr Top Med Chem ; 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315367

RESUMO

Peptidomimetics are studied for medicinal application because of its ability to mimic hierarchical structures of peptides and proteins. To break the limitation and expand the peptidomimetics family, a new class of peptidomimetics based on peptide nucleic acids (PNAs) backbone - "γ-AApeptides" was developed. Compared with previous peptidomimetics, γ-AApeptides possess prominent advantages such as resistance to proteolytic degradation, enhanced chemodiversity, good selectivity and outstanding bioactivity. The synthesis of γ-AApeptides is using a ''monomer building block'' strategy which is facile and efficient. γ-AApeptides are able to mimic primary and secondary structures of therapeutic peptides which make them promising candidates for molecular probes and potential drug leads. In the past decade, several interesting structures and applications of γ-AApeptides have been developed by different approaches such as structure-based design, combinatorial library screening, and peptides self-assembly and folding. By following the mechanism of host-defense peptides (HDPs), antibiotic γ-AApeptides showed broad-spectrum activity. At the same time, γ-AApeptides can be used for combinatorial library screening because of their structural stability and their chemodiversity. Anti-cancer agents, anti-T2DM (Type 2 diabetes mellitus) agents, anti-HIV (human immuno-deficiency virus) agents and anti-Alzheimer's disease agents were developed by combinatorial screening and rational deign. Furthermore, γ-AApeptides as biopolymers, nanomaterials, supramolecular structures and self-assembly architectures were studied due to their unique backbone structures. Therefore, γ-AApeptides may play an important role in the development of peptidomimetics.

18.
Med Image Anal ; 73: 102163, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34303170

RESUMO

As an extreme type of partial auditory deprivation, single-sided deafness (SSD) has been demonstrated to lead to extensive neural plasticity according to multimodal neuroimaging studies. Among them, resting-state functional magnetic resonance imaging (rs-fMRI) offers valuable information on functional connectivities (FCs). However, most previous SSD rs-fMRI studies assumed that the extracted FC remains stationary during the entire fMRI scan and neglected dynamic functional activities. Existing fixed window-based dynamic FC analysis also ignores dynamic functional activities under different temporal terms. Additionally, due to the cost constraints of using MRI machines, using data-driven methods for unbiased hypothesis investigations may require more effective sample data augmentation techniques. To tackle these challenges and problems together, in this study, we proposed a dynamic window with a random length and position to extract participants' dynamic characteristics under different temporal terms and to extract more information from the dataset. Then, we proposed a nodal efficiency-based correlation matrix to describe the relationships of synergism between regions as features and applied a linear support vector machine (SVM) model to learn the importance of the features, which helped to identify SSD patients and healthy controls. A total of 68 participants (including 23 with left SSD, 20 with right SSD and 25 healthy controls) were enrolled. Our proposed approach with a random window showed clear improvement compared with traditional static and fixed window-based dynamic FC by using the linear SVM model. FCs related to the frontoparietal, somatomotor, dorsal attention, limbic and default mode networks played significant roles in differentiating SSD patients from healthy controls. Additionally, FCs between the somatomotor and frontoparietal networks made the greatest contribution to the classification model. Regarding brain regions, FCs related to the superior frontal gyrus, superior parietal lobule, superior temporal gyrus, amygdala, and orbital gyrus played significant roles. These findings suggest that networks and regions related to higher-order cognitive functions showed the most significant FC alterations in SSD, which may represent a compensatory collaboration of cognitive resources in SSD.


Assuntos
Encéfalo , Surdez , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Cognição , Humanos , Imageamento por Ressonância Magnética , Vias Neurais
19.
Int J Mol Sci ; 22(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200743

RESUMO

Mastitis is a common disease in dairy cows that is mostly caused by E. coli, and it brings massive losses to the dairy industry. N6-Methyladenosine (m6A), a methylation at the N6 position of RNA adenine, is a type of modification strongly associated with many diseases. However, the role of m6A in mastitis has not been investigated. In this study, we used MeRIP-seq to sequence the RNA of bovine mammary epithelial cells treated with inactivated E. coli for 24 h. In this in vitro infection model, there were 16,691 m6A peaks within 7066 mRNA transcripts in the Con group and 10,029 peaks within 4891 transcripts in the E. coli group. Compared with the Con group, 474 mRNAs were hypermethylated and 2101 mRNAs were hypomethylated in the E. coli group. Biological function analyses revealed differential m6A-modified genes mainly enriched in the MAPK, NF-κB, and TGF-ß signaling pathways. In order to explore the relationship between m6A and mRNA expression, combined MeRIP-seq and mRNA-seq analyses revealed 212 genes with concomitant changes in the mRNA expression and m6A modification. This study is the first to present a map of RNA m6A modification in mastitis treated with E. coli, providing a basis for future research.


Assuntos
Adenosina/análogos & derivados , Metilação de DNA , Células Epiteliais/metabolismo , Infecções por Escherichia coli/veterinária , Regulação da Expressão Gênica , Glândulas Mamárias Animais/metabolismo , Mastite Bovina/genética , Adenosina/química , Animais , Bovinos , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/imunologia , Feminino , Perfilação da Expressão Gênica , Glândulas Mamárias Animais/imunologia , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/imunologia , Mastite Bovina/microbiologia
20.
Neuroimage ; 240: 118382, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34252524

RESUMO

Self-construal (orientations of independence and interdependence) is a fundamental concept that guides human behaviour, and it is linked to a large number of brain regions. However, understanding the connectivity of these regions and the critical principles underlying these self-functions are lacking. Because brain activity linked to self-related processes are intrinsic, the resting-state method has received substantial attention. Here, we focused on resting-state functional connectivity matrices based on brain asymmetry as indexed by the differential partition of the connectivity located in mirrored positions of the two hemispheres, hemispheric specialization measured using the intra-hemispheric (left or right) connectivity, brain communication via inter-hemispheric interactions, and global connectivity as the sum of the two intra-hemispheric connectivity. Combining machine learning techniques with hypothesis-driven network mapping approaches, we demonstrated that orientations of independence and interdependence were best predicted by the asymmetric matrix compared to brain communication, hemispheric specialization, and global connectivity matrices. The network results revealed that there were distinct asymmetric connections between the default mode network, the salience network and the executive control network which characterise independence and interdependence. These analyses shed light on the importance of brain asymmetry in understanding how complex self-functions are optimally represented in the brain networks.


Assuntos
Encéfalo/fisiologia , Rede de Modo Padrão/fisiologia , Função Executiva/fisiologia , Lateralidade Funcional/fisiologia , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Rede de Modo Padrão/diagnóstico por imagem , Feminino , Humanos , Masculino , Adulto Jovem
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