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1.
Int J Gen Med ; 14: 8389-8397, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34819747

RESUMO

Objective: The majority of giant cell tumors of bone (GCTB) occur in adult patients, especially between the ages of 20 and 40. This study aims to investigate the imaging features of GCTBs in pediatric patients and compare their characteristics with adult cases. Methods: Fifty-seven cases of patients aged 18 years old or younger were retrospectively analyzed, accounting for 12.8% of GCTBs in the First Affiliated Hospital of Zhengzhou University from 2001 to 2019. One hundred twenty-six adult patients (19 years of age and older) with GCTB occurring in long tubular bones were also included in this study. The following clinical information was identified from the medical records: age, sex, and follow-up data. Imaging features were reviewed by two musculoskeletal radiologists. Patient characteristics and imaging features between the two groups were compared. Results: A total of 57 patients (32 females, 25 males) were included in the study. The patients' ages ranged from 9 to 18 (median = 17 y). The majority of tumors occurred in tubular bones (n = 38, 66.7%) and the pelvis (n = 8, 14.0%). Imaging features were identified in GCTB cases occurring in the long tubular bones. Compared with adult GCTB patients, pediatric GCTB patients had a larger superior-inferior (SI) diameter (P = 0.005) and smaller left-to-right diameter/SI diameter ratio (P = 0.001). Epiphyseal involvement was relatively less common in pediatric patients with GCTBs than in adult patients (P = 0.009). The median age of patients without epiphyseal involvement was lower than the median age of patients with epiphyseal involvement (11 vs 17 y). Conclusion: GCTB in the pediatric age group is rare. This study has found that, in pediatric patients with GCTBs, the epiphysis is relatively less involved, and the tumor is more likely to grow longitudinally. These findings are helpful in the diagnosis of GCTBs in the pediatric population.

2.
Chem Commun (Camb) ; 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34812801

RESUMO

The construction of heteroporous covalent organic frameworks (COFs) is still a challenge. Herein, a series of 2D COFs with hexagonal and quadrilateral pores were constructed via in situ salphen or metal salphen formation. Metallized salphen-based COFs can be used as electrocatalysts towards water oxidation with an overpotential of 266 mV at 10 mA cm-2.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34726693

RESUMO

OBJECTIVES: To determine the transmission and molecular characteristics of blaNDM-producing Escherichia coli between companion animals and their healthcare providers at veterinary clinics in Guangzhou, China. METHODS: A total of 359 samples from companion animals and their healthcare providers were collected at 14 veterinary clinics in Guangzhou, China. Genomic characteristics and clonal relationships for blaNDM-positive E. coli and complete plasmid sequences were characterized based on WGS data from combined Illumina and MinION platform reads. RESULTS: Forty-five blaNDM-positive bacteria were recovered from companion animals (n = 43) and their healthcare providers (n = 2) at 10 veterinary clinics. Overall, E. coli (73.3%, 33/45) and Klebsiella pneumoniae (13.3%, 6/45) were the most prevalent species among the seven species of blaNDM-positive bacteria. Four blaNDM variants (blaNDM-1, blaNDM-4, blaNDM-5 and blaNDM-7) were identified in 45 blaNDM-positive bacteria and blaNDM-5 was the most prevalent (77.8%, 35/45). WGS indicated that the most prevalent STs were ST405 (8/33), ST453 (6/33), ST457 (6/33) and ST410 (5/33) among the 33 blaNDM-positive E. coli isolates. Phylogenomics and PFGE analysis revealed that clonal spread of blaNDM-positive ST453 E. coli isolates between companion animals and their healthcare providers was evident. In addition, two novel IncFIB plasmids carrying blaNDM-4 (pF765_FIB and pG908_FIB) were found in this study and indicated that IS26 may promote the horizontal transmission of blaNDM between different plasmid types. CONCLUSIONS: In this study we conducted a large-scale investigation on the prevalence of blaNDM-positive E. coli isolates from companion animals and their healthcare providers and revealed the clonal spread of blaNDM-positive E. coli isolates between these two groups.

4.
Front Psychol ; 12: 741821, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603160

RESUMO

Background: In the face of the 2019 Coronavirus Disease (COVID-19) outbreak, Chinese medical students worried about their future studies which might make them more susceptible to academic anxiety. Previous studies have shown that academic anxiety is an important risk factor for self-handicapping, but there are few studies to explore the relationship between the two which may be mediated or moderated by other variables. Therefore, this study investigated how Chinese medical students' academic anxiety is correlated to their self-handicapping in time of COVID-19 epidemic, and explored the moderating and mediating effects of hardiness and procrastination. Methods: In this study, 320 Chinese medical students' psychological traits were measured with Academic Anxiety Questionnaire, Self-Handicapping Scale, General Procrastination Scale and Hardiness Scale to explore the potential associations between these variables. Results: The most obvious finding to emerge from this study was that self- handicapping had a positive correlation with academic anxiety and procrastination, but had a negative correlation with hardiness; hardiness had a negative association with academic anxiety and procrastination; and academic anxiety and procrastination were positively correlated. In addition, the relationship between academic anxiety and self-handicapping of Chinese medical students was not only partially mediated by procrastination, but also moderated by hardiness. Furthermore, medical students who had lower hardiness had stronger direct effect, while the indirect effect was strong at high and low conditions of hardiness. Conclusion: In time of the COVID-19 epidemic, the academic anxiety and self-handicapping of medical students are influenced by procrastination and hardiness to a great extent. Thus, in addition to suggesting that more attention should be paid to the academic anxiety and procrastination of medical students, in the future, more attention should be paid to cultivating the hardiness of medical students and exerting its interventional role in self-handicapping.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34718439

RESUMO

OBJECTIVE: To investigate the associations of mitochondrial DNA (mtDNA) genetic variants with systemic lupus erythematosus (SLE) susceptibility, glucocorticoids (GCs) efficacy, and prognosis. METHODS: Our study was done in two stages. First, we performed the whole mitochondrial genome sequencing in 100 patients and 100 controls to initially screen potential mtDNA variants associated with disease and glucocorticoids efficacy. Then, we validated the results in an independent set of samples. In total, 605 SLE patients and 604 normal controls were included in our two-stage study. A two-stage efficacy study was conducted in 512 patients treated with GCs for 12 weeks. We also explored the association between mtDNA variants and SLE prognosis. RESULTS: In the combined sample, four mtDNA variants (A4833G, T5108C, G14569A, CA514-515-) were associated with SLE susceptibility (all P  BH<0.05). We confirmed that T16362C was related to GCs efficacy (P  BH=0.014). Significant associations were detected between T16362C and T16519C and the efficacy of GCs in females with SLE (P  BH<0.05). In the prognosis study, variants A4833G (P  BH=0.003) and G14569A (P  BH=9.744 × 1 0 -4) substantially increased SLE relapse risk. Female patients harbouring variants T5108C and T16362C were more prone to relapse (P  BH<0.05). Haplotype analysis showed that haplogroup G was linked with SLE susceptibility (P  BH=0.001) and prognosis (P  BH=0.013). Moreover, mtDNA variants-environment interactions were observed. CONCLUSION: We identified novel mtDNA genetic variants that were associated with SLE susceptibility, GCs efficacy, and prognosis. Interactions between mtDNA variants and environmental factors were related to SLE risk and GCs efficacy. Our findings provide important information for future understanding the occurrence and development of SLE.

6.
Front Neurol ; 12: 666750, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539543

RESUMO

Background: Traumatic spinal cord injury (SCI) can result in severe disability and causes a considerable socio-economic burden worldwide. Circular RNAs (circRNAs) are important regulators of gene expression and pathological processes, and may represent therapeutic targets for SCI. To further evaluate the role of circRNAs in SCI, we elucidated circRNA expression profiles related to vascular endothelial proliferation, migration, and angiogenesis during the early stages of secondary injury in a mouse model of SCI. Methods: Microarray analysis was performed to investigate the circRNA expression patterns in the spinal cord 3 days after SCI in female mice. Bioinformatic analyses, including GO enrichment analysis, KEGG pathway analysis, and circRNA-miRNA-mRNA network construction, were conducted to explore the role of circRNA dysregulation in vascular endothelial proliferation, migration, and angiogenesis following SCI. Results: The expression of 1,288 circRNAs was altered (>2-fold change, p < 0.05) in the spinal cord after SCI, consisting of 991 upregulated and 297 downregulated circRNAs. We constructed a circRNA-mRNA network to predict whether these circRNAs could act as "miRNA sponges." We next assessed the association of altered circRNAs with vascular endothelial proliferation, migration, and angiogenesis using GO and KEGG analyses. Using this analysis, we found that a total of 121 circRNAs were correlated with vascular endothelial proliferation, migration, and angiogenesis in the spinal cord after SCI. Conclusions: Our study provides circRNA expression profiles during the early stages of SCI. circRNA.7079, circRNA.7078, and circRNA.6777 were found to play key roles in the vascular endothelial proliferation, migration, and angiogenesis, and may represent therapeutic targets for SCI.

7.
Zhongguo Zhen Jiu ; 41(7): 742-6, 2021 Jul 12.
Artigo em Chinês | MEDLINE | ID: mdl-34259405

RESUMO

OBJECTIVE: To compare the efficacy between acupuncture-moxibustion treatment by stages and femoston for premature ovarian insufficiency (POI). METHODS: A total of 66 patients with POI were randomly divided into an observation group (33 cases, 3 cases dropped off) and a control group (33 cases, 2 cases dropped off). The patients in the observation group, based on the theory of "transformation of yin and yang", were treated with acupuncture-moxibustion by stages in the postmenstrual period, ovulatory period, premenstrual period and menstrual period, once every other day, 3 times a week. The patients in the control group were treated with oral administration of femoston (estradiol tablets/estradiol and dydrogesterone tablets, 1 tablet per day). Both groups were treated for 3 menstrual cycles. The ovarian function (serum follicle-stimulating hormone [FSH], luteinizing hormone [LH], estradiol [E2], anti-mullerian hormone [AMH] and antral follicle count [AFC]) and perimenopausal symptoms [modified Kupperman index (KI) scale score] were observed before and after treatment, and the menstrual improvement of the two groups was compared. RESULTS: Compared before treatment, the serum levels of FSH and LH were decreased (P<0.01), the levels of E2 were increased (P<0.01) in the two groups after treatment; the serum level of AMH and AFC in the observation group were increased after treatment (P<0.01). After treatment, the serum level of AMH and AFC in the observation group were higher than those in the control group (P<0.05). After treatment, there was no significant difference in the menstrual return rate and menstrual regularity rate between the amenorrhea patients of the two groups (P>0.05). After treatment, the modified KI scale scores in the two groups were reduced (P<0.01), and the modified KI scale score in the observation group was lower than that in the control group (P<0.05). CONCLUSION: Acupuncture- moxibustion treatment by stages based on the theory of "transformation of yin and yang" has similar efficacy with femoston in improving serum sex hormone level and menstrual symptoms in patients with POI, and has advantages in improving serum AMH level, AFC and perimenopausal symptoms.


Assuntos
Terapia por Acupuntura , Moxibustão , Insuficiência Ovariana Primária , Pontos de Acupuntura , Feminino , Hormônio Foliculoestimulante , Humanos , Insuficiência Ovariana Primária/terapia
8.
FEBS Open Bio ; 11(9): 2453-2467, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34233080

RESUMO

Flow cytometric sorting is a vital tool in biological research and clinical diagnostics. Theoretically, a high-speed jet-in-air sorter is a fluorescent-activated cell sorting sorter that ideally processes cells with high purity, yield, and viability. However, high-speed jet-in-air sorting is a complex process due to its inherent requirements for high fluidic stability and electronic and timing precision. Here, we report that an additional manual correction of drop delay leads to improved cell yield. Adding 2% FBS to the loading buffer had no significant effect on the fate of sorted cells in 4 h. However, the addition of a suitable concentration of FBS/BSA in the collecting buffer resulted in a notable increase in cell count and proliferation and a significant decrease in cell apoptosis for cell lines and primary cells. Moreover, the level of gene expression remained steady in the 5% FBS collecting buffer. In summary, here we demonstrate techniques that can be easily followed to refine sorted yields of healthy cells.

9.
Cell Prolif ; 54(8): e13092, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34189783

RESUMO

T cells participate in the repair process and immune response in the CNS post-traumatic injury and play both a beneficial and harmful role. Together with nerve cells and other immune cells, they form a microenvironment in the CNS post-traumatic injury. The repair of traumatic CNS injury is a long-term process. T cells contribute to the repair of the injury site to influence the recovery. Recently, with the advance of new techniques, such as mass spectrometry-based flow cytometry, modern live-cell imaging, etc, research focusing on T cells is becoming one of the valuable directions for the future therapy of traumatic CNS injury. In this review, we summarized the infiltration, contribution and regulation of T cells in post-traumatic injury, discussed the clinical significance and predicted the future research direction.


Assuntos
Sistema Nervoso Central/metabolismo , Transtornos de Estresse Pós-Traumáticos/patologia , Linfócitos T/imunologia , Barreira Hematoencefálica/imunologia , Barreira Hematoencefálica/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Sistema Nervoso Central/imunologia , Citocinas/metabolismo , Humanos , Transtornos de Estresse Pós-Traumáticos/imunologia , Transtornos de Estresse Pós-Traumáticos/metabolismo , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo
10.
Inorg Chem ; 60(8): 5627-5634, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33794094

RESUMO

Two novel layered compounds BaCuSi2Pn3 (Pn = P, As) adopting new structure types are reported. As revealed by single-crystal X-ray diffraction, both compounds are composed of unique Cu-Si-Pn layers featuring CuPn3 and Si2Pn6 structural motifs found in other archetypal pnictide materials. The stacking of the isostructural Cu-Si-Pn layers is different for phosphide and arsenide compounds. Synthesis from elements aided by in situ synchrotron powder X-ray diffraction resulted in the obtainment of bulk powders with a minimized amount of admixtures. Experimentally measured physical properties of BaCuSi2As3 unexpectedly showed metal-like behavior at temperatures above 15 K, despite the fact that density functional theory calculations predict a small band gap of 0.4 eV. BaCuSi2As3 exhibits ultralow thermal conductivity, which can be explained by the combination of a layered crystal structure with alternating covalent and ionic bonding, which feature rattling of Cu atoms similar to that in tetrahedrites.

11.
Front Neurosci ; 15: 644239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33841083

RESUMO

The central nervous system (CNS) post-traumatic injury can cause severe nerve damage with devastating consequences. However, its pathophysiological mechanisms remain vague. There is still an urgent need for more effective treatments. Circular RNAs (circRNAs) are non-coding RNAs that can form covalently closed RNA circles. Through second-generation sequencing technology, microarray analysis, bioinformatics, and other technologies, recent studies have shown that a number of circRNAs are differentially expressed after traumatic brain injury (TBI) or spinal cord injury (SCI). These circRNAs play important roles in the proliferation, inflammation, and apoptosis in CNS post-traumatic injury. In this review, we summarize the expression and functions of circRNAs in CNS in recent studies, as well as the circRNA-miRNA-mRNA interaction networks. The potential clinical value of circRNAs as a therapeutic target is also discussed.

12.
Nat Commun ; 12(1): 1855, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767195

RESUMO

Time reversal symmetric (TRS) invariant topological insulators (TIs) fullfil a paradigmatic role in the field of topological materials, standing at the origin of its development. Apart from TRS protected strong TIs, it was realized early on that more confounding weak topological insulators (WTI) exist. WTIs depend on translational symmetry and exhibit topological surface states only in certain directions making it significantly more difficult to match the experimental success of strong TIs. We here report on the discovery of a WTI state in RhBi2 that belongs to the optimal space group P[Formula: see text], which is the only space group where symmetry indicated eigenvalues enumerate all possible invariants due to absence of additional constraining crystalline symmetries. Our ARPES, DFT calculations, and effective model reveal topological surface states with saddle points that are located in the vicinity of a Dirac point resulting in a van Hove singularity (VHS) along the (100) direction close to the Fermi energy (EF). Due to the combination of exotic features, this material offers great potential as a material platform for novel quantum effects.

13.
Chemistry ; 27(26): 7383-7390, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33523500

RESUMO

Three novel isostructural equiatomic gold tetrel pnictides, AuSiAs, AuGeP, and AuGeAs, were synthesized and characterized. These phases crystallize in the noncentrosymmetric (NCS) monoclinic space group Cc (no. 9), featuring square-planar Au within cis-[AuTt2 Pn2 ] units (Tt=tetrel, Si, Ge; Pn=pnictogen, P, As). This is in drastic contrast to the structure of previously reported AuSiP, which exhibits typical linear coordination of Au with Si and P. Chemical bonding analysis through the electron localization function suggests covalent two-center two-electron Tt-Pn bonds, and three-center Au-Tt-Au and Au-Pn-Au bonds with 1.6 e- per bond. X-ray photoelectron spectroscopy studies support the covalent and nonionic nature of Au-Pn and Au-Tt bonds. The title materials were found to be n-type narrow-gap semiconductors or semimetals, with nearly temperature-independent electrical resistivities and low thermal conductivities. A combination of the semimetallic properties with tunable NCS structure provides opportunities for the development of materials based on gold tetrel pnictides.

14.
Toxicol Appl Pharmacol ; 414: 115428, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33524449

RESUMO

Researches have shown that calcitonin gene-related peptide (CGRP) plays a pivotal role in pain modulation. Nociceptive information from the periphery is relayed from parabrachial nucleus (PBN) to brain regions implicated involved in pain. This study investigated the effects and mechanisms of CGRP and CGRP receptors in pain regulation in the PBN of naive and neuropathic pain rats. Chronic sciatic nerve ligation was used to model neuropathic pain, CGRP and CGRP 8-37 were injected into the PBN of the rats, and calcitonin receptor-like receptor (CLR), a main structure of CGRP receptor, was knocked down by lentivirus-coated CLR siRNA. The hot plate test (HPT) and the Randall Selitto Test (RST) was used to determine the latency of the rat hindpaw response. The expression of CLR was detected with RT-PCR and western blotting. We found that intra-PBN injecting of CGRP induced an obvious anti-nociceptive effect in naive and neuropathic pain rats in a dose-dependent manner, the CGRP-induced antinociception was significantly reduced after injection of CGRP 8-37, Moreover, the mRNA and protein levels of CLR, in PBN decreased significantly and the antinociception CGRP-induced was also significantly lower in neuropathic pain rats than that in naive rats. Knockdown CLR in PBN decreased the expression of CLR and the antinociception induced by CGRP was observably decreased. Our results demonstrate that CGRP induced antinociception in PBN of naive or neuropathic pain rats, CGRP receptor mediates this effect. Neuropathic pain induced decreases in the expression of CGRP receptor, as well as in CGRP-induced antinociception in PBN.


Assuntos
Analgésicos/farmacologia , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Proteína Semelhante a Receptor de Calcitonina/agonistas , Dor Nociceptiva/prevenção & controle , Limiar da Dor/efeitos dos fármacos , Núcleos Parabraquiais/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/agonistas , Ciática/prevenção & controle , Animais , Proteína Semelhante a Receptor de Calcitonina/genética , Proteína Semelhante a Receptor de Calcitonina/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Masculino , Dor Nociceptiva/genética , Dor Nociceptiva/metabolismo , Dor Nociceptiva/fisiopatologia , Núcleos Parabraquiais/metabolismo , Núcleos Parabraquiais/fisiopatologia , Ratos Sprague-Dawley , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/genética , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Ciática/genética , Ciática/metabolismo , Ciática/fisiopatologia
15.
Adv Physiol Educ ; 45(1): 24-30, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33439782

RESUMO

A novel educational tool helps teach intestinal absorption in physiology-We have designed an interesting educational tool to help sophomores learn intestinal absorption in physiology course. In the study group (2019), 51 sophomores from biomedical engineering were encouraged to learn the intestinal absorption knowledge through reading materials and group discussion. Then, using the form of flipped class, they stepped on the podium and simulated and explained the absorption processes with designed paper props as educational tool. In contrast, the control group (2018), 52 sophomores from the same specialty had taken the same professional courses before. The result of theoretical test showed the average score in the study group was higher than that in the control group. The questionnaire analysis showed the positive role of the education tool in their learning efficacy. To sum up, using our tool has achieved better teaching effects than the traditional lecture.


Assuntos
Fisiologia , Aprendizagem Baseada em Problemas , Avaliação Educacional , Escolaridade , Humanos , Absorção Intestinal , Aprendizagem , Fisiologia/educação , Ensino
16.
Nat Mater ; 20(3): 329-334, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33462464

RESUMO

Dissipationless currents from topologically protected states are promising for disorder-tolerant electronics and quantum computation. Here, we photogenerate giant anisotropic terahertz nonlinear currents with vanishing scattering, driven by laser-induced coherent phonons of broken inversion symmetry in a centrosymmetric Dirac material ZrTe5. Our work suggests that this phononic terahertz symmetry switching leads to formation of Weyl points, whose chirality manifests in a transverse, helicity-dependent current, orthogonal to the dynamical inversion symmetry breaking axis, via circular photogalvanic effect. The temperature-dependent topological photocurrent exhibits several distinct features: Berry curvature dominance, particle-hole reversal near conical points and chirality protection that is responsible for an exceptional ballistic transport length of ~10 µm. These results, together with first-principles modelling, indicate two pairs of Weyl points dynamically created by B1u phonons of broken inversion symmetry. Such phononic terahertz control breaks ground for coherent manipulation of Weyl nodes and robust quantum transport without application of static electric or magnetic fields.

17.
Theor Appl Genet ; 134(1): 327-337, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33068118

RESUMO

KEY MESSAGE: A minor QTL for grain weight in rice, qTGW1.2b, was fine-mapped. Its casual gene OsVQ4 was confirmed through CRISPR/Cas9-targeted mutagenesis, exhibiting an effect that was larger than the original QTL effect. The CRISPR/Cas system exhibits a great potential for rice improvement, but the application was severely hindered due to insufficient target genes, especial the lack of validated genes underlying quantitative trait loci having small effects. In this study, a minor QTL for grain weight, qTGW1.2b, was fine-mapped into a 44.0 kb region using seven sets of near isogenic lines (NILs) developed from the indica rice cross (Zhenshan 97)3/Milyang 46, followed by validation of the causal gene using CRISPR/Cas9-targeted mutagenesis. In the NIL populations, 1000-grain weight of the Zhenshan 97 homozygous lines decreased by 0.9-2.0% compared with the Milyang 46 homozygous lines. A gene encoding VQ-motif protein, OsVQ4, was identified as the candidate gene based on parental sequence differences. The effect of OsVQ4 was confirmed by creating CRISPR/Cas9 knockout lines, whose 1000-grain weight decreased by 2.8-9.8% compared with the wild-type transgenic line and the recipient. These results indicate that applying genome editing system could create novel alleles with large phenotypic variation at minor QTLs, which is an effective way to validate causal genes of minor QTLs. Our study establishes a strategy for cloning minor QTLs, which could also be used to identify a large number of potential target genes for the application of CRISPR/Cas system.


Assuntos
Oryza/genética , Locos de Características Quantitativas , Sementes/crescimento & desenvolvimento , Sistemas CRISPR-Cas , Mapeamento Cromossômico , Edição de Genes , Técnicas de Inativação de Genes , Genes de Plantas , Mutagênese
18.
J Ethnopharmacol ; 268: 113556, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33157223

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Astragaloside IV (AST IV) is the active component of Astragalus membranaceus (Fisch.) Bunge, which regulates lipid and carbohydrate metabolism and improves insulin resistance. In this study, we investigated the effects of AST IV on insulin resistant cells and a non-alcoholic fatty liver disease (NAFLD) model induced by high-concentration insulin or oleic acid (OA) in HepG2 cells, as well as the associated regulatory markers. METHODS: First, the target of AST IV was predicted via pharmacophore model matching and molecular docking. Then, enzyme kinetics experiments were conducted in vitro to determine the effect of AST IV on the target protein. Next, AST IV's toxicity was tested on HepG2 cells in vitro, through an insulin resistance model and an NAFLD model, by high-concentration insulin or OA, respectively. To explore the effects of AST IV on insulin resistance and lipid metabolism, we detected the related indexes of glucose and lipid metabolism through commercially available kits. Relevant proteins were also detected by Western blot to provide future direction for study. RESULTS: Our preliminary results of pharmacophore model matching and molecular docking suggested that AST IV and protein tyrosine phosphatase 1B (PTP1B) can be well-combined through hydrogen bonding. Further, the enzyme kinetics experiment showed that AST IV was an effective and specific inhibitor to PTP1B. We found that the protein level of PTP1B in HepG2 cells was significantly increased after treating with high-concentration insulin or OA. Additionally, the intervention of AST IV significantly increased glucose consumption in an insulin resistance model and reduced the content of triglyceride (TG), total cholesterol (TC), and free fatty acid (FFA) in the NAFLD model. Moreover, the 2-N-(7-nitrobenze-2-oxa-1, 3 diazol-4-yl) (2-NBDG) uptake rate in the NAFLD model was also greatly improved. These results validated the effects of AST IV on improving insulin resistance and lipid accumulation. Furthermore, Western blot results illustrated that AST IV suppressed PTP1B and increased levels of phosphorylated insulin receptor (p-IR) and phosphorylated insulin receptor substrate-1 (p-IRS-1) in insulin-resistant HepG2 cells, while also decreasing protein levels of PTP1B and sterol element regulatory binding protein-1c (SREBP-1c) in the NAFLD model. CONCLUSION: This study demonstrated that AST IV inhibited PTP1B and effectively improved insulin resistance in insulin-resistant HepG2 cells and triglyceride accumulation in OA-treated HepG2 cells.


Assuntos
Resistência à Insulina/fisiologia , Ácido Oleico/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Saponinas/farmacologia , Triglicerídeos/metabolismo , Triterpenos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/farmacologia , Células Hep G2 , Humanos
19.
J Antimicrob Chemother ; 76(2): 322-329, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33057710

RESUMO

OBJECTIVES: To determine the dissemination and molecular characteristics of NDM-producing Escherichia coli strains from duck farms in south-east coastal China and their threats to human health. METHODS: A total of 232 NDM-producing E. coli were recovered from 1505 samples collected from 25 duck farms and their surrounding environments in five provinces in China. Resistance genes were confirmed using PCR. Genomic characteristics of the carbapenemase-producing isolates were determined by WGS and bioinformatic analysis. RESULTS: The rate of NDM-positive E. coli detected in samples from the five provinces ranged from 3.7% to 28.5%. There was substantial variation in the prevalence of NDM-positive E. coli from different duck farms in each province studied. Three variants (blaNDM-1, blaNDM-4 and blaNDM-5) were found in 232 NDM-positive E. coli; blaNDM-5 (94.8%, 220/232) was the most prevalent. WGS analysis indicated that ST746, ST48, ST1011 and ST167 E. coli isolates were prevalent in the current study and poultry was likely the primary reservoir for NDM-positive ST746 and ST48 E. coli in China. Phylogenomic analysis showed that NDM-positive E. coli isolates from ducks were closely related to those of human origin. In addition, WGS analysis further revealed that blaNDM co-existed with other antibiotic resistance genes, conferring resistance to nine classes of antimicrobials. CONCLUSIONS: This study revealed that ducks farm in China are an important reservoir for NDM-positive E. coli and STs of the isolates showed obvious distinctive diversities in geographical distribution. The distribution and spread of NDM-positive E. coli in duck farms poses a threat to public health.


Assuntos
Patos , Escherichia coli , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias , China/epidemiologia , Escherichia coli/genética , Fazendas , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , beta-Lactamases/genética
20.
Artigo em Inglês | MEDLINE | ID: mdl-33062019

RESUMO

The roots of Polygonum multiflorum (PM) (He Shou Wu in Chinese) are one of the most commonly used tonic traditional Chinese medicines (TCMs) in China. PM is traditionally valued for its antiaging, liver- and kidney-tonifying, and hair-blackening effects. However, an increasing number of hepatotoxicity cases induced by PM attract the attention of scholars worldwide. Thus far, the potential liver injury compounds and the mechanism are still uncertain. The aim of this review is to provide comprehensive information on the potential hepatotoxic components and mechanism of PM based on the scientific literature. Moreover, perspectives for future investigations of hepatotoxic components are discussed. This study will build a new foundation for further study on the hepatotoxic components and mechanism of PM.

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