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1.
Plant Physiol ; 192(2): 1483-1497, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36810650

RESUMO

Glandular secretory trichomes (GSTs) can secrete and store a variety of specific metabolites. By increasing GST density, valuable metabolites can be enhanced in terms of productivity. However, the comprehensive and detailed regulatory network of GST initiation still needs further investigation. By screening a complementary DNA library derived from young leaves of Artemisia annua, we identified a MADS-box transcription factor, AaSEPALLATA1 (AaSEP1), that positively regulates GST initiation. Overexpression of AaSEP1 in A. annua substantially increased GST density and artemisinin content. The HOMEODOMAIN PROTEIN 1 (AaHD1)-AaMYB16 regulatory network regulates GST initiation via the jasmonate (JA) signaling pathway. In this study, AaSEP1 enhanced the function of AaHD1 activation on downstream GST initiation gene GLANDULAR TRICHOME-SPECIFIC WRKY 2 (AaGSW2) through interaction with AaMYB16. Moreover, AaSEP1 interacted with the JA ZIM-domain 8 (AaJAZ8) and served as an important factor in JA-mediated GST initiation. We also found that AaSEP1 interacted with CONSTITUTIVE PHOTOMORPHOGENIC 1 (AaCOP1), a major repressor of light signaling. In this study, we identified a MADS-box transcription factor that is induced by JA and light signaling and that promotes the initiation of GST in A. annua.


Assuntos
Artemisia annua , Tricomas , Tricomas/genética , Tricomas/metabolismo , Artemisia annua/genética , Artemisia annua/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ciclopentanos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Plant Cell Rep ; 43(2): 45, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38261110

RESUMO

KEY MESSAGE: A high-efficiency protoplast transient system was devised to screen genome editing elements in Salvia miltiorrhiza. Medicinal plants with high-value pharmaceutical ingredients have attracted research attention due to their beneficial effects on human health. Cell wall-free protoplasts of plants can be used to evaluate the efficiency of genome editing mutagenesis. The capabilities of gene editing in medicinal plants remain to be fully explored owing to their complex genetic background and shortfall of suitable transformation. Here, we took the Salvia miltiorrhiza as a representative example for developing a method to screen favorable gene editing elements with high editing efficiency in medical plants by a PEG-mediated protoplast transformation. Results indicated that using the endogenous SmU6.1 of S. miltiorrhiza to drive sgRNA and the plant codon-optimized Cas9 driven by the promoter SlEF1α can enhance the efficiency of editing. In summary, we uncover an efficacious transient method for screening editing elements and shed new light on increasing gene editing efficiency in medicinal plants.


Assuntos
Salvia miltiorrhiza , Humanos , Salvia miltiorrhiza/genética , Edição de Genes , Protoplastos , RNA Guia de Sistemas CRISPR-Cas , Parede Celular
3.
Nano Lett ; 23(1): 107-115, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36541945

RESUMO

In comparison to the well-developed proton-exchange-membrane fuel cells, anion-exchange-membrane fuel cells (AEMFCs) permit adoption of platinum-group-metal (PGM)-free catalysts due to the alkaline environment, giving a substantial cost reduction. However, previous AEMFCs have generally shown unsatisfactory performances due to the lack of effective PGM-free catalysts that can endure harsh fuel cell conditions. Here we report a plasma-assisted synthesis of high-quality nickel nitride (Ni3N) and zirconium nitride (ZrN) employing dinitrogen as the nitrogen resource, exhibiting exceptional catalytic performances toward hydrogen oxidation and oxygen reduction in an alkaline enviroment, respectively. A PGM-free AEMFC assembled by using Ni3N as the anode and ZrN as the cathode delivers power densities of 256 mW cm-2 under an H2-O2 condition and 151 mW cm-2 under an H2-air condition. Furthermore, the fuel cell shows no evidence of degradation after 25 h of operation. This work creates opportunities for developing high-performance and durable AEMFCs based on metal nitrides.


Assuntos
Níquel , Platina , Membranas , Membrana Celular , Ânions , Prótons
4.
BMC Public Health ; 23(1): 1486, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542247

RESUMO

BACKGROUND: Little is known about the potential mechanisms of healthy eating and exercise change, and design interventions which aim to promote healthy eating and exercise change among individuals at risk of metabolic syndrome. This study aimed to identify key determinants of healthy eating, exercise behaviors, and health among individuals at risk of metabolic syndrome using the integrated common-sense model of illness self-regulation. METHOD: A cross-sectional study with a multi-wave data collection strategy. A total of 275 participants at risk of metabolic syndrome based on the clinical prediction model were included in the final analysis. Path analysis was employed to explore the pattern of relationships between key variables using AMOS. RESULTS: The mediation analysis suggested that personal and treatment control, and coherence can positively affect self-reported health via intentions and health behaviors (exercise and healthy eating). Additionally, relationships between self-efficacy (exercise and healthy eating) and health outcomes can be mediated by health behaviors, and both intentions and health behaviors. CONCLUSIONS: This current research used the integrated common-sense model of illness self-regulation to predict healthy eating, exercise behaviors, and self-reported health among individuals at risk of metabolic syndrome. The results suggested that self-efficacy, intention, consequences, personal control, treatment control, and coherence were the key determinants of behavior and health, which can help design interventions to encourage healthy eating and exercise changes among individuals with a high risk of MetS.


Assuntos
Síndrome Metabólica , Autocontrole , Humanos , Síndrome Metabólica/epidemiologia , Comportamento Alimentar , Dieta Saudável , Estudos Transversais , Modelos Estatísticos , Inquéritos e Questionários , Prognóstico , Comportamentos Relacionados com a Saúde
5.
Knee Surg Sports Traumatol Arthrosc ; 31(8): 3141-3150, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36562809

RESUMO

PURPOSE: Closing wedge distal femoral osteotomies (CWDFO) are attractive treatment options for unicompartmental knee osteoarthritis with coronal plane deformity. However, it has been traditionally associated with high rates of hinge fracture that can adversely impact recovery and patient outcomes. Appropriate siting of hinge point can be an effective method of reducing the incidence of hinge fractures. This study aims to illustrate a case series of CWDFO with low rates of hinge fracture utilising our preferred hinge point site. METHODS: A retrospective study of a cohort of 39 CWDFO was performed between May 2019 and May 2022. Both medial and lateral CWDFO were included. The hinge point in all cases was placed at the level of the inferior margin of the metaphyseal flare, and inferior to the gastrocnemius origin, with a hinge thickness of 10 mm. Post-operative radiographs were obtained at 2, 4 and 8 weeks after surgery to assess for hinge fracture and union. RESULTS: Thirty-nine cases of CWDFO were performed, consisting of eighteen cases of valgus malalignment that underwent medial CWDFO and twenty-one cases of varus malalignment that underwent lateral CWDFO. At surgery, the mean age was 47.6 (± 13.9) years and mean BMI was 29.4 (± 4.9). There were 23 men and 16 women. Three cases of hinge fractures occurred intraoperatively, translating into a hinge fracture rate of 7.69%. However, union was achieved in all three cases and all patients in this case series were able to progress to weight bear as tolerated at 2 months post-osteotomy. CONCLUSION: Distal placement of the hinge at the level of the inferior metaphyseal flare margin with the use of a hinge wire can greatly reduce the rates of hinge fracture in CWDFO. LEVEL OF EVIDENCE: Level III.


Assuntos
Fraturas Ósseas , Osteoartrite do Joelho , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Fêmur/cirurgia , Estudos Retrospectivos , Osteoartrite do Joelho/cirurgia , Osteotomia/efeitos adversos , Osteotomia/métodos , Tíbia/cirurgia
6.
Genomics ; 114(5): 110452, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35988655

RESUMO

To explore the key lncRNAs affecting postmenopausal osteoporosis (PMOP) progression, the transcriptome sequencing of peripheral blood mononuclear cells from fifteen early postmenopausal women, according to bone mineral density, were divided into groups of osteoporosis, osteopenia and normality, in each of which the expression profiles of lncRNAs was investigated. From the results we observed nine candidates of lncRNAs, which were to be compared with miRBase, and found that MIR22HG as one candidate of lncRNA was most likely to be directly used as miRNA precursor. Based on the KEGG annotation and lncRNA-miRNA-mRNA-KEGG network, we analyzed the potential role of candidate lncRNAs. The results showed that the expression profiles of lncRNAs could help identify the novel ones involved in the progression of PMOP, and that MIR22HG could serve as a miRNA precursor to regulate FoxO signaling pathway in bone metabolism. Our findings can be of great help in predicting and diagnosing early PMOP.


Assuntos
MicroRNAs , Osteoporose Pós-Menopausa , RNA Longo não Codificante , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoporose Pós-Menopausa/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/metabolismo
7.
Int J Mol Sci ; 24(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37629108

RESUMO

The plant Artemisia annua L. is famous for producing "artemisinin", which is an essential component in the treatment of malaria. The glandular secretory trichomes (GSTs) on the leaves of A. annua secrete and store artemisinin. Previous research has demonstrated that raising GST density can effectively raise artemisinin content. However, the molecular mechanism of GST initiation is not fully understood yet. In this study, we identified an MYB transcription factor, the AaMYB108-like, which is co-induced by light and jasmonic acid, and positively regulates glandular secretory trichome initiation in A. annua. Overexpression of the AaMYB108-like gene in A. annua increased GST density and enhanced the artemisinin content, whereas anti-sense of the AaMYB108-like gene resulted in the reduction in GST density and artemisinin content. Further experiments demonstrated that the AaMYB108-like gene could form a complex with AaHD8 to promote the expression of downstream AaHD1, resulting in the initiation of GST. Taken together, the AaMYB108-like gene is a positive regulator induced by light and jasmonic acid for GST initiation in A. annua.


Assuntos
Artemisia annua , Artemisininas , Artemisia annua/genética , Tricomas/genética
8.
Med Mycol ; 60(2)2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35044460

RESUMO

This study aimed to detect the identification limitations for Aspergillus species from patients or the environment based on MALDI-TOF MS analysis. A total of 209 Aspergillus isolates were selected in this study. One hundred and sixty-eight of the strains were selected as challenge strains for MALDI-TOF MS analysis, while the remaining 41 strains were used to construct a supplementary database. The 168 challenge strains were identified by the Bruker Filamentous Fungi Library v1.0 (the Bruker Library) and identified again using the Bruker Library combined with the supplementary database (the combined database). The sensitivity of MALDI-TOF MS with the Bruker Library alone and with the combined database in identifying the challenge strains at the species level was 64.3 and 85.7%, respectively. With the combined database, the sensitivity of MALDI-TOF MS in identifying strains in Aspergillus sections Fumigati, Flavi, Nigri, Terrei, and Nidulantes was 100, 86.5, 76.1, 100, and 80%, respectively, and the sensitivity in identifying strains of other Aspergillus species was 71.4%. The specificity of MALDI-TOF MS in identifying strains in all Aspergillus sections at the species level was 100%. Even when using the combined database, MALDI-TOF MS analysis showed some misidentification for the species A. niger, A. welwitschiae, A. luchuensis, A. flavus and A. sydowii. In conclusion, with the combined database, MALDI-TOF MS showed good performance in identifying the species in Aspergillus sections Fumigati and Terrei but limited performance in distinguishing some closely related species in sections Nigri, Flavi and Nidulantes. LAY SUMMARY: MALDI-TOF MS showed good performance in identifying Aspergillus species in sections Fumigati and Terrei but limited performance in distinguishing some closely related species in sections Nigri, Flavi and Nidulantes.


Assuntos
Aspergillus , Fungos , Animais , Lasers , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária
9.
Genomics ; 113(3): 1514-1521, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33785399

RESUMO

To explore the role of plasma miRNAs in exosomes in early postmenopausal women. Small RNA sequencing was implemented to clarify the expression of miRNA in plasma exosomes obtained from 15 postmenopausal women, divided into groups of osteoporosis, osteopenia, and normal bone mass based on bone mineral density. Differentially expressed miRNAs (DEMs) were identified by comparing miRNA expression profiles. Five putative miRNAs, miR-224-3p, miR-25-5p, miR-302a-3p, miR-642a-3p, and miR-766-5p were confirmed by real-time PCR; miRNA target genes were obtained from 4 databases: miRWalk, miRDB, RNA22, and TargetScan. The miRNA-mRNA- Kyoto Encyclopedia of Genes and Genomes (KEGG) networks were analyzed, and the DEMs' potential role was investigated by gene ontology terms and KEGG pathway annotation. The results suggest that characterizing plasma exosomal miRNA profiles of early postmenopausal women by small RNA sequencing could identify novel exo-miRNAs involved in bone remodeling, and miR-642a-3p maybe contribute to the prediction and diagnosis of early postmenopausal osteoporosis.


Assuntos
Densidade Óssea , MicroRNAs , Exossomos , Feminino , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Humanos , MicroRNAs/metabolismo , Pós-Menopausa , Análise de Sequência de RNA
10.
N Engl J Med ; 379(11): 1028-1041, 2018 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-30207916

RESUMO

BACKGROUND: Allogeneic hematopoietic stem-cell transplantation is the only curative treatment for patients with myelodysplastic syndrome (MDS). The molecular predictors of disease progression after transplantation are unclear. METHODS: We sequenced bone marrow and skin samples from 90 adults with MDS who underwent allogeneic hematopoietic stem-cell transplantation after a myeloablative or reduced-intensity conditioning regimen. We detected mutations before transplantation using enhanced exome sequencing, and we evaluated mutation clearance by using error-corrected sequencing to genotype mutations in bone marrow samples obtained 30 days after transplantation. In this exploratory study, we evaluated the association of a mutation detected after transplantation with disease progression and survival. RESULTS: Sequencing identified at least one validated somatic mutation before transplantation in 86 of 90 patients (96%); 32 of these patients (37%) had at least one mutation with a maximum variant allele frequency of at least 0.5% (equivalent to 1 heterozygous mutant cell in 100 cells) 30 days after transplantation. Patients with disease progression had mutations with a higher maximum variant allele frequency at 30 days than those who did not (median maximum variant allele frequency, 0.9% vs. 0%; P<0.001). The presence of at least one mutation with a variant allele frequency of at least 0.5% at day 30 was associated with a higher risk of progression (53.1% vs. 13.0%; conditioning regimen-adjusted hazard ratio, 3.86; 95% confidence interval [CI], 1.96 to 7.62; P<0.001) and a lower 1-year rate of progression-free survival than the absence of such a mutation (31.3% vs. 59.3%; conditioning regimen-adjusted hazard ratio for progression or death, 2.22; 95% CI, 1.32 to 3.73; P=0.005). The rate of progression-free survival was lower among patients who had received a reduced-intensity conditioning regimen and had at least one persistent mutation with a variant allele frequency of at least 0.5% at day 30 than among patients with other combinations of conditioning regimen and mutation status (P≤0.001). Multivariate analysis confirmed that patients who had a mutation with a variant allele frequency of at least 0.5% detected at day 30 had a higher risk of progression (hazard ratio, 4.48; 95% CI, 2.21 to 9.08; P<0.001) and a lower 1-year rate of progression-free survival than those who did not (hazard ratio for progression or death, 2.39; 95% CI, 1.40 to 4.09; P=0.002). CONCLUSIONS: The risk of disease progression was higher among patients with MDS in whom persistent disease-associated mutations were detected in the bone marrow 30 days after transplantation than among those in whom these mutations were not detected. (Funded by the Leukemia and Lymphoma Society and others.).


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mutação , Síndromes Mielodisplásicas/genética , Adulto , Exame de Medula Óssea , Análise Mutacional de DNA , Progressão da Doença , Intervalo Livre de Doença , Humanos , Leucemia Mieloide Aguda/genética , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/terapia , Pele/patologia , Análise de Sobrevida , Condicionamento Pré-Transplante , Transplante Homólogo
11.
Biol Res ; 54(1): 42, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930472

RESUMO

Osteoporosis (OP), a common systemic metabolic bone disease, is characterized by low bone mass, increasing bone fragility and a high risk of fracture. At present, the clinical treatment of OP mainly involves anti-bone resorption drugs and anabolic agents for bone, but their long-term use can cause serious side effects. The development of stem cell therapy and regenerative medicine has provided a new approach to the clinical treatment of various diseases, even with a hope for cure. Recently, the therapeutic advantages of the therapy have been shown for a variety of orthopedic diseases. However, these stem cell-based researches are currently limited to animal models; the uncertainty regarding the post-transplantation fate of stem cells and their safety in recipients has largely restricted the development of human clinical trials. Nevertheless, the feasibility of mesenchymal stem cells to treat osteoporotic mice has drawn a growing amount of intriguing attention from clinicians to its potential of applying the stem cell-based therapy as a new therapeutic approach to OP in the future clinic. In the current review, therefore, we explored the potential use of mesenchymal stem cells in human OP treatment.


Assuntos
Reabsorção Óssea , Células-Tronco Mesenquimais , Osteoporose , Animais , Camundongos , Osteoporose/terapia
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(3): 357-363, 2021 May.
Artigo em Zh | MEDLINE | ID: mdl-34018351

RESUMO

Hydroxyapatite (HAp) is the main inorganic component of the bones and teeth, and it possesses bioactivity and biocompatibility. However, due to its poor mechanical performance, slow degradation speed, and lack of diversity in its function, it is difficult to apply HAp alone as a scaffold material for bone tissue engineering. By combining HAp with other types of materials, composite materials with specific properties can be prepared, and the scopes of HAp applications can be expanded. Firstly, we elaborated on the importance, and strengths and weaknesses of HAp for bone tissue engineering biomaterials and then reviewed the research status of HAp composite materials used in bone regeneration. Secondly, about hot research topics in the field of applying HAp composite materials in bone repair, we summarized the representative findings in the field, and discussions and analysis were made accordingly. Finally, we also examined the future development prospects of HAp composite bone repair materials.


Assuntos
Durapatita , Engenharia Tecidual , Materiais Biocompatíveis , Osso e Ossos , Alicerces Teciduais
13.
Angew Chem Int Ed Engl ; 60(12): 6553-6560, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33438257

RESUMO

Although the Turing structures, or stationary reaction-diffusion patterns, have received increasing attention in biology and chemistry, making such unusual patterns on inorganic solids is fundamentally challenging. We report a simple cation exchange approach to produce Turing-type Ag2 Se on CoSe2 nanobelts relied on diffusion-driven instability. The resultant Turing-type Ag2 Se-CoSe2 material is highly effective to catalyze the oxygen evolution reaction (OER) in alkaline electrolytes with an 84.5 % anodic energy efficiency. Electrochemical measurements show that the intrinsic OER activity correlates linearly with the length of Ag2 Se-CoSe2 interfaces, determining that such Turing-type interfaces are more active sites for OER. Combing X-ray absorption and computational simulations, we ascribe the excellent OER performance to the optimized adsorption energies for critical oxygen-containing intermediates at the unconventional interfaces.

14.
Angew Chem Int Ed Engl ; 60(52): 26922-26931, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34553478

RESUMO

Electrosynthesis of hydrogen peroxide (H2 O2 ) in the acidic environment could largely prevent its decomposition to water, but efficient catalysts that constitute entirely earth-abundant elements are lacking. Here we report the experimental demonstration of narrowing the interlayer gap of metallic cobalt diselenide (CoSe2 ), which creates high-performance catalyst to selectively drive two-electron oxygen reduction toward H2 O2 in an acidic electrolyte. The enhancement of the interlayer coupling between CoSe2 atomic layers offers a favorable surface electronic structure that weakens the critical *OOH adsorption, promoting the energetics for H2 O2 production. Consequently, on the strongly coupled CoSe2 catalyst, we achieved Faradaic efficiency of 96.7 %, current density of 50.04 milliamperes per square centimeter, and product rate of 30.60 mg cm-2 h-1 . Moreover, this catalyst shows no sign of degradation when operating at -63 milliamperes per square centimeter over 100 hours.

15.
Pak J Pharm Sci ; 34(2): 513-519, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34275824

RESUMO

Severe oxidative stress triggered by acute hypobaric hypoxia (AHH) is harmful for lots of organs in body, especial brain and heart. Flavonoids with antioxidant properties can protect organs from oxidative stress. Our previous study found that 5,6,7,8-trtrahydroxyflavone (5,6,7,8-THF), a flavones with four consecutive hydrogen group on ring A, showed excellent antioxidant properties in vitro. In the present study, the protective of 5,6,7,8-THF against oxidative stress caused by AHH was investigated. Mice were administered with 5,6,7,8-THF(500mg/kg) for 5 consecutive days before HH exposure. The heart rate (HR) and blood pressure (BP) was measured. The activity of SOD, CAT, GSH-Px, LDH, Na+-K+-ATPase and Ca2+-Mg2+-ATPase and the content of H2O2, MDA, LD and ATP in brain and heart tissue was evaluated using commercial kit. AHH led to a significant increase in HR and decrease in BP. Pretreatment of 5,6,7,8-THF could reversed these changes. In addition, administration of 5,6,7,8-THF could significantly increase the activity of SOD, CAT and GSH-Px and decrease the content of H2O2 and MDA in the brain and heart of mice under AHH. Furthermore, 5,6,7,8-THF inhibited the activity of LDH, decreased the level of LD and improved ATPase activity. These results indicate that 5,6,7,8-THF may protect the mice against AHH injury via scavenging free radical, inhibiting lipid peroxidation, enhancing antioxidant enzyme activity, preserving energy metabolism and can be further explored as an excellent anti-hypoxia agent for preventing acute mountain sickness.


Assuntos
Encéfalo/efeitos dos fármacos , Coração/efeitos dos fármacos , Hipóxia/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Flavonas/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , L-Lactato Desidrogenase/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/metabolismo , Malondialdeído/metabolismo , Camundongos , Miocárdio/metabolismo , Pressão Parcial , Taxa de Sobrevida
16.
Biochem Cell Biol ; 98(3): 345-353, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31689131

RESUMO

Hypoxia induces cellular oxidative stress that is associated with neurodegenerative diseases. HPN (4'-hydroxyl-2-substituted phenyl nitronyl nitroxide), a stable nitronyl nitroxide, has excellent free radical scavenging properties. The purpose of this study was to investigate the protective effects of HPN on hypoxia-induced damage in PC12 cells. It was shown that HPN significantly attenuated hypoxia-induced loss of cell viability, release of lactate dehydrogenase (LDH), and morphological changes in PC12 cells. Moreover, hypoxic PC12 cells had increased levels of reactive oxygen species (ROS), malondialdehyde (MDA), and expression of HIF-1α and VEGF, but had reduced levels of superoxide dismutase (SOD) and catalase (CAT), and HPN reversed these changes. HPN also inhibited hypoxia-induced cell apoptosis via suppressing the expression of Bax, cytochrome c, and caspase-3, and inducing the expression of Bcl-2. These results indicate that the protective effects of HPN on hypoxia-induced damage in PC12 cells is associated with the suppression of hypoxia-induced oxidative stress and cell apoptosis. HPN could be a promising candidate for the development of a novel neuroprotective agent.


Assuntos
Apoptose , Hipóxia Celular/efeitos dos fármacos , Óxidos de Nitrogênio/farmacologia , Animais , Antioxidantes/metabolismo , Caspase 3/metabolismo , Citocromos c/metabolismo , Sequestradores de Radicais Livres/farmacologia , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos , Malondialdeído/metabolismo , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismo , Proteína X Associada a bcl-2/metabolismo
17.
Biochem Biophys Res Commun ; 521(1): 9-14, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31630797

RESUMO

Osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (BMSCs) has been regarded as a central issue in fracture healing. MicroRNAs (miRNAs, miRs) participate in diverse physiological processes such as osteoblastic differentiation of BMSCs. In this study, we found that miR-664a-5p was upregulated during osteogenic differentiation of human BMSCs, and this upregulation positively correlated with the expression of osteogenic genes Runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), and osteocalcin (OCN). Overexpression of miR-664a-5p promoted the osteogenic differentiation of BMSCs, whereas a knockdown of miR-664a-5p suppressed it. Additionally, high-mobility group A2 (HMGA2) mRNA was identified as a direct target of miR-664a-5p that mediates the function of this miRNA. Overexpression of HMGA2 obviously attenuated miR-664a-5p-induced osteogenic differentiation of BMSCs. Thus, the newly identified miR-664a-5p-HMGA2 pathway expands our understanding of the mechanisms underlying the osteogenic differentiation of human BMSCs, may provide deeper insights into the regulation of this differentiation, and can point to new effective methods for treating osteoporosis.


Assuntos
Regulação para Baixo , Proteína HMGA2/metabolismo , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Medula Óssea/metabolismo , Diferenciação Celular , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/citologia , MicroRNAs/genética , Osteogênese
18.
J Vasc Interv Radiol ; 31(6): 869-875, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32331919

RESUMO

This paper describes country-wide special measures undertaken for interventional radiology staff during the current coronavirus disease 2019 (COVID-19) pandemic. Although each interventional radiology service around the world faces unique challenges, the principles outlined in this article will be useful when designing or strengthening individual practices and integrating them within wider hospital and national measures. Moving beyond the current outbreak, these measures will be useful for any future infectious diseases which are likely to arise.


Assuntos
Infecções por Coronavirus/complicações , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/complicações , Pneumonia Viral/prevenção & controle , Radiologia Intervencionista/métodos , COVID-19 , Humanos , Singapura
19.
Med Mycol ; 58(1): 66-70, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31329921

RESUMO

Common histopathologic techniques are used to diagnose fungal infections, but the diagnostic identification of mycoses in tissue specimens is often difficult, particularly when fungi rarely occur in a specimen. The aim of this study was to evaluate the application of fluorescein-labeled chitinase staining to formalin-fixed and paraffin-embedded (FFPE) tissues. We studied 79 archival FFPE tissues from patients diagnosed with fungal disease, including 38 cases of sporotrichosis and 41 cases of other fungal infections. The tissue sections were subjected to periodic acid-Schiff (PAS) staining, Gomori's methenamine silver (GMS) staining, and fluorescein-labeled chitinase staining to detect fungal elements. Culture- and/or hematoxylin-eosin-positive samples were used to estimate the diagnostic sensitivity of each staining method, with the results showing that PAS, GMS, and fluorescein-labeled chitinase staining had sensitivities of 50.6, 70.9, and 68.4%, respectively. The three staining results were the same for all fungal infections except for sporotrichosis and chromoblastomycosis. Fluorescein-labeled chitinase staining exhibited high sensitivity in cases of sporotrichosis and poor performance in detecting muriform cells of chromoblastomycosis. On the whole, the sensitivity of fluorescein-labeled chitinase staining was greater than that of PAS and similar to that of GMS staining. Therefore, the results of our study suggest that fluorescein-labeled chitinase staining is a potentially useful diagnostic tool in the diagnosis of fungal infections.


Assuntos
Quitinases/química , Fluoresceína/química , Micoses/diagnóstico , Coloração e Rotulagem , Bancos de Espécimes Biológicos , Fluorescência , Formaldeído , Humanos , Micoses/microbiologia , Inclusão em Parafina , Sensibilidade e Especificidade
20.
Exp Cell Res ; 383(1): 111491, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31288024

RESUMO

Transmembrane protein 18 (Tmem18) is an obesity-associated gene essential for adipogenesis; however, its function in the osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) is still unclear. In this study, we found that Tmem18 was significantly downregulated in rat BMSCs after osteogenic induction. TMEM18 overexpression remarkably downregulated osteo-specific genes including alkaline phosphatase (Alp), Runt-related transcription factor 2 (Runx2), osteocalcin (Ocn), and osteopontin (Opn), and reduced the number of mineral deposits and ALP activity in vitro, whereas knockdown of Tmem18 yielded the opposite results. In vivo assays also indicated that TMEM18 knockdown BMSCs have an increased bone formation potential in a rat model of calvarial defects. Analyses of the mechanism suggested that TMEM18 overexpression decreased ß-catenin expression, whereas the TMEM18 knockdown enhanced ß-catenin expression and promoted its nuclear translocation. The positive effects on osteogenic differentiation of rat BMSCs owing to the TMEM18 knockdown were attenuated by ß-catenin downregulation. Taken together, these results indicate that TMEM18 plays an inhibitory role in osteogenic differentiation of BMSCs via inactivation of ß-catenin.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Osteogênese , beta Catenina/antagonistas & inibidores , Animais , Células Cultivadas , Regulação para Baixo , Proteínas de Membrana/administração & dosagem , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Ratos , Ratos Sprague-Dawley
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