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1.
J Microbiol Methods ; : 106319, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34480973

RESUMO

Pathogens within Fusarium species are the primary agents of Fusarium head blight (FHB) of wheat, which bring about yield reduction and deoxynivalenol (DON) contamination and are of great concern worldwide. DON-producing Fusarium species can be classified into 3-acetyldeoxynivalenol (3ADON) and 15-acetyldeoxynivalenol (15ADON) chemotypes according to the trichothecene metabolites they produce. The detection of these two chemotypes of pathogens is paramount to the successful implementation of disease management strategies and pathogen-related DON forecasting models. In this study, a duplex droplet digital PCR (duplex ddPCR) assay was developed that allowed for the simultaneous quantitation of 3ADON and 15ADON chemotypes of DON-producing Fusarium species. The assay specificity was tested against 30 isolates of target Fusarium species and several non-target Fusarium species that are frequently isolated from wheat in China. Analyzing 90 wheat samples collected from the North China plain and Yangtze River plain demonstrated that the duplex ddPCR assay coupled with magnetic bead-based DNA extraction was competent for investigating composition of 3ADON and 15ADON chemotypes in Chinese wheat. This assay will be useful for monitoring the epidemic and geographic distribution of 3ADON and 15ADON chemotypes of FHB pathogens, which will help with the disease control and DON management.

2.
PLoS One ; 16(9): e0251937, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34506505

RESUMO

Pine wilt disease (PWD) is a devastating disease affecting trees belonging to the genus Pinus. To control the spread of PWD in the Masson pine forest in China, PWD resistant Masson pine clones have been selected by the Anhui Academy of Forestry. However, because Masson pine is a difficult-to-root species, producing seedlings is challenging, especially from trees older than 5 years of age, which impedes the application of PWD resistant clones. In this study, we investigated the factors affecting rooting of PWD resistant clones and established a cheap, reliable, and simple method that promotes rooting. We tested the effects of three management methods, four substrates, two cutting materials, two cutting treatments, and three collection times on the rooting of cuttings obtained from 9-year-old PWD resistant clones. Rooting was observed only in stem cuttings treated with the full-light automatic spray management method. Additionally, stem cuttings showed a significantly higher rooting rate and root quality than needles cuttings. Compared with other substrates, stem cuttings planted in perlite produced the longest adventitious root and the highest total root length and lateral root number. Moreover, stem cuttings of PWD resistant clones collected in May showed a significantly higher rooting rate and root quality than those collected in June and July. Moreover, stem cuttings prepared with a horizontal cut while retaining the needles showed significantly higher rooting rate and root quality than those prepared with a diagonal cut while partly removing the needles. This study promotes the reproduction of seedlings of PWD-resistant Masson pine clones which helps control the spread of PWD, meanwhile, provides a technical reference for the propagation of mature pine trees via cuttings.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34499596

RESUMO

A Gram-stain-negative, coccus-shaped, obligately anaerobic, non-motile and non-spore-forming bacterium, designated strain JN500902T, was isolated from the mud in a fermentation cellar used continuously over 30 years for Chinese strong-flavour baijiu production. Colonies were white, circular, convex and smooth-edged. Growth was observed at 20-40 °C (optimum, 37 °C), at pH 5.0-10 (optimum, pH 7.5), with 0-2 % (w/v) NaCl and with 0-4 % (v/v) ethanol. The Biolog assay demonstrated positive reactions of strain JN500902T in the metabolism of l-fucose and pyruvate. The predominant cellular fatty acids (>10 %) consisted of C16 : 0 and C14 : 0. The major end metabolites of strain JN500902T were acetic acid and ethanol when incubated anaerobically in liquid reinforced clostridial medium. Acetate was the major organic acid end product. The complete genome size of strain JN500902T was 3 420 321 bp with 3327 identified genes. The G+C content was 43.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences affiliated strain JN500902T with the family Lachnospiraceae, having low sequence similarity (92.8 %) to the nearest type strain, Syntrophococcus sucromutans DSM 3224T and forming a clearly distinct branch. Core genome phylogenetic analysis of the isolate and 134 strains belonging to the family Lachnospiraceae also revealed that strain JN500902T was well-separated from other genera of this family as a monophyletic clade. The average nucleotide identity and amino acid identity values between strain JN500902T and 134 Lachnospiraceae strains were less than 74 and 65 %, respectively. Considering its polyphasic characteristics, strain JN500902T represents a novel genus and species within the family Lachnospiraceae, for which the name Novisyntrophococcus fermenticellae gen. nov., sp. nov. is proposed. The type strain is JN500902T (=CICC 24502T=JCM 33939T).


Assuntos
Clostridiales/classificação , Fermentação , Filogenia , Microbiologia do Solo , Anaerobiose , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Clostridiales/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
4.
J Biomater Appl ; : 8853282211036535, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34496655

RESUMO

Due to its high wear resistance and good biocompatibility, zirconia toughened alumina (ZTA) is an ideal material used as load-bearing implant. However, ZTA needs to be modified to overcome its bio-inert and thus improve osseointegration. Cerium oxide, which has been proved to be a bone-friendly ceramic, might be a desired material to enhance the bioactivity of ZTA. In this study, ZTA and cerium oxide doped ZTA (ZTAC) were prepared via sintering method. The in vitro study showed that the addition of cerium oxide promoted MC3T3-E1 cell adhesion and spreading through upregulating ITG α5 and ITG ß1. In addition, the incorporation of cerium oxide enhanced cell proliferation, ALP activity, and ECM mineralization capacity. Moreover, the incorporation of cerium oxide promoted the expressions of osteogenesis related genes, such as ALP, Col-I, and OCN. The in vivo implantation test via a SD rat model showed that the incorporation of cerium oxide promoted new bone formation and bone-implant integration. In summary, this study provided a new strategy to fabricate bioactive ZTA implant for potential application in orthopedics field.

5.
Eur J Oncol Nurs ; 54: 102039, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34537537

RESUMO

PURPOSE: Despite increasing research on posttraumatic growth (PTG) of spouses of cancer patients, and the positive effects of spouses' PTG on both spouses and patients, there is little information on PTG and its correlates among husbands of gynecological cancer survivors, especially those of newly diagnosed survivors. We aimed to assess PTG among spouses of newly diagnosed gynecological cancer survivors and to examine its correlates. METHODS: In a cross-sectional study, a total of 400 spouses of newly diagnosed gynecological cancer survivors were recruited and completed questionnaires with information on general characteristics, rumination, self-disclosure, locus of control, and PTG. Univariate analysis and multiple linear regression analysis were performed. RESULTS: The mean score of PTG among the spouses was 57.77 (SD = 12.03). There were significant differences in PTG among spouses with different education levels, marriage duration, number of children, per capita monthly income, other traumatic events within 6 months, and time since diagnosis groups. Pearson's correlation analysis revealed that deliberate rumination, self-disclosure, and locus of control were significantly associated with PTG. The multiple regression model revealed that 53.6% of the variance in PTG was explained by marriage duration, time since diagnosis, self-disclosure, deliberate rumination, and internality locus of control. CONCLUSIONS: This study was one of the early attempts in evaluating PTG among spouses of newly diagnosed gynecological cancer survivors and identified several significant, potentially modifiable factors (self-disclosure, deliberate rumination, and internality locus of control) associated with PTG, providing an important guide for the development of effective psychosocial interventions for this population.

6.
Waste Manag ; 135: 130-139, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34496309

RESUMO

Aerobic composting is a promising alternative for the recycling of rice straw (RS), and an applicable nitrogen source is necessary to improve the process. The aim of this study was to compare the performance and microbial community dynamics of RS composting using urea or protein hydrolysate from leather waste (PHL) as a nitrogen source. Results showed that PHL addition achieved a faster temperature increase rate at start-up (1.85 ℃·h-1 vs 1.07 ℃·h-1), higher volatile solid degradation efficiency (48.04% vs 46.98%), and greater germination indices (111.72% vs 89.87%) in the end products, as compared to urea. The major bacterial phyla included Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria in both composting processes. Although the bacterial communities in both processes succeeded in a similar pattern according to different composting phases, PHL addition accelerated the succession rate of the microbial community. Co-occurrence network analysis revealed that bacterial community composition was strongly correlated with physicochemical properties such as dissolved organic carbon (DOC), NH4+, pH, temperature, and total nitrogen (TN) content. These results proved the potential of using PHL as a nitrogen source to improve the RS composting process.

7.
J Biomol Struct Dyn ; : 1-12, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34353233

RESUMO

Chinese hazelnut was chosen to become a probable precursor of biological active peptides via computer simulations in this article. There were a large number of bioactive peptides in Chinese hazelnut sequences according to analytical results from the BIOPEP database. The most prominent of these was the inhibitory peptide for dipeptidyl peptidase-IV (DPP-IV; EC 3.4.14.5), which can be used to treat type 2 diabetes, so the theoretical method to obtain DPP-IV inhibitory peptides by hydrolysis with a single or combination of enzymes was studied. Cytotoxicity analysis performed by ToxinPred showed that all of the DPP-IV inhibitory peptides generated from protein hydrolysis were not cytotoxic. Structural interaction fingerprint analysis revealed that Asp663 and Phe357 may be important residues for ligand binding. In order to further understand the inhibitory mechanism of peptide, VR with lowest half maximum inhibitory concentration (IC50) and IPI (inhibitors have been reported) were selected as ligand of DPP-IV to perform steered molecular dynamics simulations and PMF calculations. The results showed that P1 is the preferred (un)binding tunnel for the inhibitors obtained. Our findings help in the development of new DPP-IV inhibitors which were derived from common food.Communicated by Ramaswamy H. Sarma.

8.
Talanta ; 234: 122653, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34364462

RESUMO

Deoxynivalenol (DON) contamination in wheat flour induces a number of adverse health effects to consumers and livestock, even at very low concentrations. Direct detection methods for massive screening of DON in wheat flour is still lacking. A new methodology integrating multi-molecular infrared spectroscopy (MM-IR) with two-trace two-dimensional correlation spectroscopy (2T-2DCOS) was developed for in-situ qualitative and quantitative determination of DON in wheat flour as a whole. Typical spectral variation of wheat flour samples with diverse concentration of DON were stepwise characterized by MM-IR and tiny spectral profile differences resulting from concentration variation of DON were visually disclosed by 2T-2DCOS. Based on the obtained key spectral features of DON, 180 of wheat flour samples with DON higher and lower than 1.00 mg/kg were undoubtedly classified by Principal Component Analysis (PCA) and Support Vector Machines (SVM) with an accuracy rate up to 100% (for Second derivative spectra consisted of selected bands, SD-SS). Furthermore, a robust quantitative prediction model was established based on partial least squares (PLS) of SD-SS (Rc: 0.998, RMSEC: 0.135; Rp: 0.968, RMSEP: 0.421), and its excellent predictive capacity of model was validated by both residual prediction deviation (RPD) value of 3.2 and t-test. It was demonstrated that the developed methodology was applicable for screening and quantitative detection of DON in wheat flour based on the novel correlation analysis methods (SD-2DCOS-IR and 2T-2DCOS-IR) with chemometrics tools, which could be utilized both at laboratory and industrial level for quality control purposes of a large wheat flour sample set.


Assuntos
Farinha , Triticum , Farinha/análise , Contaminação de Alimentos/análise , Humanos , Análise dos Mínimos Quadrados , Espectrofotometria Infravermelho
9.
Cell Death Differ ; 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34363017

RESUMO

Hematopoietic stem cell (HSC) fate is tightly controlled by various regulators, whereas the underlying mechanism has not been fully uncovered due to the high heterogeneity of these populations. In this study, we identify tetraspanin CD63 as a novel functional marker of HSCs in mice. We show that CD63 is unevenly expressed on the cell surface in HSC populations. Importantly, HSCs with high CD63 expression (CD63hi) are more quiescent and have more robust self-renewal and myeloid differentiation abilities than those with negative/low CD63 expression (CD63-/lo). On the other hand, using CD63 knockout mice, we find that loss of CD63 leads to reduced HSC numbers in the bone marrow. In addition, CD63-deficient HSCs exhibit impaired quiescence and long-term repopulating capacity, accompanied by increased sensitivity to irradiation and 5-fluorouracil treatment. Further investigations demonstrate that CD63 is required to sustain TGFß signaling activity through its interaction with TGFß receptors I and II, thereby playing an important role in regulating the quiescence of HSCs. Collectively, our data not only reveal a previously unrecognized role of CD63 but also provide us with new insights into HSC heterogeneity.

10.
Food Res Int ; 147: 110449, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399451

RESUMO

Mud cellars have long been used as anaerobic bioreactors for the fermentation of Chinese strong-flavor Baijiu, where starchy raw materials (mainly sorghum) are metabolized to ethanol and various flavor compounds by multi-species microorganisms. Jiupei (fermented grains) and pit mud are two spatially linked microbial habitats in the mud cellar, yet their metabolic division of labor remains unclear. Here, we investigated the changes in environmental variables (e.g., temperature, oxygen, pH), key metabolites (e.g., ethanol, organic acids) and microbial communities in jiupei and pit mud during fermentation. Jiupei (low pH, high ethanol) and pit mud (neutral pH) provided two habitats with distinctly different environmental conditions for microbial growth. Lactic acid accumulated in jiupei, while butyric and hexanoic acids were mainly produced by microbes inhabiting the pit mud. Biomass analysis using quantitative real-time PCR showed that bacteria dominated the microbial consortia during fermentation, moreover cluster and principal coordinate analysis (PCoA) analysis showed that the bacterial communities of jiupei and pit mud were significantly divergent. The bacterial community diversity of jiupei decreased significantly during the fermentation process, and was relatively stable in pit mud. Lactobacillus dominated the jiupei bacterial community, and its relative abundance reached 98.0% at the end of fermentation. Clostridia (relative abundance: 42.9-85.5%) was the most abundant bacteria in pit mud, mainly distributed in the genus Hydrogenispora (5.3-68.4%). Fungal communities of jiupei and pit mud showed a similar succession pattern, and Kazachstania, Aspergillus and Thermoascus were the predominant genera. PICRUSt analysis demonstrated that enzymes participating in the biosynthesis of acetic and lactic acid were mainly enriched in jiupei samples, while the bacterial community in the pit mud displayed greater potential for butyric and hexanoic acid synthesis. Assays from an in vitro simulated fermentation further validated the roles of jiupei microbiota in acetic and lactic acid production, and these acids were subsequently metabolized to butyric and hexanoic acid by the pit mud microbiota. This work has demonstrated the synergistic cooperation between the microbial communities of jiupei and pit mud for the representative flavor formation of strong-flavor Baijiu.


Assuntos
Consórcios Microbianos , Microbiota , Bebidas Alcoólicas/análise , Bactérias/genética , Fermentação
11.
Int J Hyperthermia ; 38(1): 1263-1270, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34404325

RESUMO

PURPOSE: To investigate the effects of ablation time and distance between the radiofrequency ablation (RFA) electrode tip and a large vessel on the ablation zone in beagle livers. METHODS: Sixty-one percutaneous RFA coagulation zones were created near large vessels in 10 beagle livers in vivo. The ablated lesions were divided into four groups based on ablation time and distance between the electrode tip and a large vessel (group A, 3 min 0.5 cm; group B, 3 min 0 cm; group C, 5 min 0.5 cm; group D, 5 min 0 cm). The ablated area, long-axis diameters, short-axis diameters, and vessel wall injury were examined. RESULTS: With a fixed ablation time, the ablation zone created with the electrode tip at 0.5 cm from the large vessel was significantly larger than at 0 cm (p < .05). At a fixed distance between the electrode tip and vessel, the ablation zone created for 5 min was significantly larger than for 3 min (p < .05). The frequency of vessel wall injury in the 0 cm groups was significantly higher than that in the 0.5 cm groups (37.5% vs. 6.9%; p = .003, odds ratio, 7.43). The ratio of width to depth (Dw/Dz) was larger in the 0.5 cm groups than in the 0 cm groups (p < .001). CONCLUSION: The ablation zone increased with longer ablation times and greater distances between the RFA tip and large vessels for perivascular lesions. The distance between the needle tip and blood vessels is an important factor that affects the overall ablation outcome.


Assuntos
Ablação por Cateter , Ablação por Radiofrequência , Animais , Cães , Eletrodos , Fígado/cirurgia , Agulhas
12.
Free Radic Biol Med ; 174: 144-156, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34389464

RESUMO

Ionizing radiation (IR)-induced excessive reactive oxygen species (ROS) is an important contributor of the injury of hematopoietic system. Grape seed proanthocyanidin extract (GSPE) is a new type of antioxidant, whereas whether it could ameliorate IR-induced hematopoietic injury remains unclear. Here, we show that GSPE treatment improves the survival of irradiated mice and alleviates IR-induced myelosuppression. Meanwhile, the hematopoietic reconstituting ability of hematopoietic stem cells (HSCs) in mice following irradiation exposure is significantly increased after GSPE treatment. Furthermore, GSPE treatment can reduce IR-induced ROS production and relieve DNA damage and apoptosis in hematopoietic stem progenitor cells (HSPCs). Interestingly, we find that a critical antioxidant-associated gene fokhead box transcription factor O1 (Foxo1) is significantly decreased in HSPCs after irradiation. Consistently, hematopoietic specific deletion of Foxo1 increases the radiosensitivity of mice. Further investigations reveal that GSPE treatment specifically upregulates the expression of Foxo1, as well as its target genes superoxide dismutase 1 (SOD1), superoxide dismutase 2 (SOD2) and catalase (CAT). Importantly, Foxo1 deficiency largely abolishes the radioprotection of GSPE on HSPCs. Collectively, our data demonstrate that GSPE plays an important role in ameliorating IR-induced HSPC injury via the Foxo1-mediated pathway. Therefore, GSPE may be used as a promising radioprotective agent.


Assuntos
Extrato de Sementes de Uva , Proantocianidinas , Animais , Antioxidantes/farmacologia , Proteína Forkhead Box O1/genética , Extrato de Sementes de Uva/farmacologia , Células-Tronco Hematopoéticas , Camundongos , Proantocianidinas/farmacologia , Radiação Ionizante
13.
Hum Brain Mapp ; 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34431584

RESUMO

Working memory (WM) impairments are common features of psychiatric disorders. A systematic meta-analysis was performed to determine common and disorder-specific brain fMRI response during performance of WM tasks in patients with SZ and patients with MDD relative to healthy controls (HC). Thirty-four published fMRI studies of WM in patients with SZ and 18 published fMRI studies of WM in patients with MDD, including relevant HC, were included in the meta-analysis. In both SZ and MDD there was common stronger fMRI response in right medial prefrontal cortex (MPFC) and bilateral anterior cingulate cortex (ACC), which are part of the default mode network (DMN). The effects were of greater magnitude in SZ than MDD, especially in prefrontal-temporal-cingulate-striatal-cerebellar regions. In addition, a disorder-specific weaker fMRI response was observed in right middle frontal gyrus (MFG) in MDD, relative to HC. For both SZ and MDD a significant correlation was observed between the severity of clinical symptoms and lateralized fMRI response relative to HC. These findings indicate that there may be common and distinct anomalies in brain function underlying deficits in WM in SZ and MDD, which may serve as a potential functional neuroimaging-based diagnostic biomarker with value in supporting clinical diagnosis, measuring illness severity and assessing the efficacy of treatments for SZ and MDD at the brain level.

14.
Immun Inflamm Dis ; 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34449972

RESUMO

INTRODUCTION: The prognosis of patients with glioma is dismal. It has been reported that Serpin peptidase inhibitor clade A member 3 (SERPINA3) is associated with the mobility and invasion of tumor cells. Our study was designed to explore the value of SERPINA3 messenger RNA (mRNA) expression in the biological process, prognosis, and immune significance in glioma. METHODS: We analyzed the biological functions of SERPINA3 through data from the Chinese Glioma Genome Atlas databases. Differentially expressed genes and enrichment analysis were performed and correlations between SERPINA3 expression and immune cell infiltration were analyzed. Further, we validated the expression and the survival prediction role of SERPINA3 by using tissue microarrays and RNAscope in situ hybridization in 321 gliomas. The correlations between the expression and clinical-pathological parameters as well as other biomarkers were examined. RESULTS: Univariate and multivariate regression both indicated that the level of SERPINA3 transcript represented an independent prognostic factor. High levels of SERPINA3 correlated with poor survival in patients with glioma. Expression of SERPINA3 mRNA was observed positively correlated with MCM6, IGFBP2, and FKBP10. Enrichment analysis showed SERPINA3 mainly enriched in immune-related terms and signaling pathways including MAPK, TNF, P53, PI3K-Akt, nuclear factor-κB. Immune infiltration analysis further declare the SERPINA3 expression negatively correlated with levels of Macrophages M1, native CD4+ T cell, monocytes, and Mast cell activated. And overexpression of SERPINA3 correlated with low CD4+ T cell infiltration in glioma tissues. CONCLUSIONS: SERPINA3 may play a key role in the biological process of glioma cells especially in immune suppression activities. SERPINA3 may serve as an independent survival prediction factor in glioma patients.

15.
Pathogens ; 10(8)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34451477

RESUMO

Noroviruses (NoVs), a group of single-stranded RNA viruses causing epidemic acute gastroenteritis in humans, are highly diverse, consisting of multiple genogroups with >30 genotypes. Their continual evolutions make NoV vaccine design and development difficult. Here, we report a study of NoV sequences obtained from a population-based diarrhea surveillance in Zhengding County of Hebei Province spanning from 2001 to 2019 and those available in the GenBank database from 1966 to 2019. NoV genotypes and/or variants that may evade immunity were screened and identified based on primary and conformational structures for vaccine design. We selected 366, 301, 139, 74 and 495 complete VP1-coding nucleotide sequences representing the predominant genotypes of GII.4, GII.2, GII.3, GII.6 and GII.17, respectively. A total of 16 distinct GII.4 variants were identified, showing a typical linear evolutionary pattern of variant replacement, while only 1-4 variants of the other genotypes were found to co-circulate over the 40-50-year period without typical variant replacement. The vaccine strain GII.4c is close to variant Sydney_2012 (0.053) in their primary structure, but they are distinct at epitopes A and E in conformations. Our data suggested GII.4 variant Sydney_2012, GII.2 variant A, a GII.3 strain, GII.6 variants B and C and GII.17 variant D are primary candidate strains for NoV vaccine development.

17.
Brain Res ; 1769: 147608, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343527

RESUMO

Numerous neuroimaging studies on postherpetic neuralgia (PHN) and herpes zoster (HZ) have revealed abnormalities in brain structure/microstructure and function. However, few studies have focused on changes in gray matter (GM) volume and intrinsic functional connectivity (FC) in the transition from HZ to PHN. This study combined voxel-based morphometry and FC analysis methods to investigate GM volume and FC differences in 28 PHN patients, 25 HZ patients, and 21 well-matched healthy controls (HCs). Compared to HCs, PHN patients exhibited a reduction in GM volume in the bilateral putamen. Compared with HZ patients, PHN patients showed decreased GM volume in the left parahippocampal gyrus, putamen, anterior cingulate cortex, and right caudate and increased GM volume in the right thalamus. However, no regions with significant GM volume changes were found between the HZ and HC groups. Correlation analysis revealed that GM volume in the right putamen was positively associated with illness duration in PHN patients. Furthermore, lower FCs between the right putamen and right middle frontal gyrus/brainstem were observed in PHN patients than in HCs. These results indicate that aberrant GM volumes and FC in several brain regions, especially in the right putamen, are closely associated with chronification from HZ to PHN; moreover, these changes profoundly affect multiple dimensions of pain processing. These findings may provide new insights into the pathophysiological mechanisms of PHN.

18.
Macromol Biosci ; : e2100147, 2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34272821

RESUMO

The complex, gradient physiological structure of articular cartilage is a severe hindrance of its self-repair, leaving the clinical treatment of cartilage defects a demanding issue to be addressed. Currently applied tissue engineering treatments and traditional non-tissue engineering treatments have different limitations, for example, cell dedifferentiation, immune rejection, and prosthesis-related complications. Thus, studies have been focusing on seeking promising candidates for novel cartilage repair methods. Polyvinyl alcohol (PVA) hydrogels with excellent biocompatibility and tunable material properties have become the alternatives. For pure PVA hydrogels, the mechanical strength and lubricity are not capable of replacing articular cartilage until proper modifications are done. This paper summarizes the research progress in PVA hydrogels, including the preparation, modification, and cartilage-repair-aimed biomimetic improvements. Design guidance of PVA hydrogels is put forward as assistance to functional hydrogel preparation. Finally, the prospects and main obstacles of PVA hydrogels are discussed.

19.
Biomed Mater Eng ; 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34250923

RESUMO

BACKGROUND: Transforming growth factor-ß1 (TGF-ß1) plays an important role in chondrocyte growth and the synthesis of extracellular matrix (ECM). Due to the rapid metabolism, controlled release systems for TGF-ß1 have attracted increasing interest recently. OBJECTIVE: In this study, a silk fibroin (SF)/chitosan (CS) scaffold incorporated with TGF-ß1-loaded microspheres (MSs) was created for cartilage reparation. METHOD: The optimal proportion of the SF/CS composite scaffold was determined by evaluating their micromorphology and the proliferation rate of fibroblasts on the surface. Then, SF/CS/TGF-ß1-loaded MS scaffolds were prepared by the adsorption method. TGF-ß1 release capacity, degradation patterns, cytocompatibility and in vivo implantation were evaluted. RESULTS: The SF/CS/TGF-ß1-loaded MS scaffold showed good TGF-ß1 release over more than 16 days, which could sequentially stimulate chondrocyte synthetic activity. In vitro cell proliferation experiments showed the SF/CS/TGF-ß1-loaded MS scaffold could promote chondrocytes adhesion, growth, proliferation and maintained the cellular morphology. An in vivo study demonstrated that a low inflammatory response was observed in rats and that the materials exhibited good biocompatibility. CONCLUSION: the results indicated that our SF/CS/TGF-ß1-loaded MS scaffold constitute a promising therapeutic option for cartilage reparation.

20.
J Phys Chem Lett ; : 6919-6926, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34282920

RESUMO

The present work reports highly efficient flexible and reabsorption-free scintillators based on two zero-dimensional (0D) organic copper halides (TBA)CuX2 (TBA = tetrabutylammonium cation; X = Cl, Br). The (TBA)CuX2 exhibit highly luminescent green and sky-blue emissions peaked at 510 and 498 nm, with large Stokes shifts of 224 and 209 nm and high photoluminescence quantum yields (PLQYs) of 92.8% and 80.5% at room temperature for (TBA)CuCl2 and (TBA)CuBr2 single crystals (SCs), respectively. Interestingly, above room temperature, their PLQYs increase with temperature and reach near unity at 320 and 345 K for (TBA)CuCl2 and (TBA)CuBr2, respectively. The excellent properties originate from self-trapped excitons (STEs) in individual [CuX2]- quantum rods, which is demonstrated by the temperature-dependent PL, ultrafast transient absorption (TA) combined with density functional theory (DFT) calculations. The (TBA)CuX2 scintillators show bright radioluminescence (RL), impressive linear response to dose rate in a broad range, and high light yields. Their potential application in X-ray imaging is demonstrated by using (TBA)CuX2 composite scintillation screens. Importantly, flexible scintillators are demonstrated to be superior than flat ones for imaging nonplanar objects by conformally coating, which produce accurate images with negligible distortion.

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