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1.
Nat Commun ; 15(1): 518, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225235

RESUMO

The construction of N-N axially chiral motifs is an important research topic, owing to their wide occurrence in natural products, pharmaceuticals and chiral ligands. One efficient method is the atroposelective dihydropyrimidin-4-one formation. We present herein a direct catalytic synthesis of N-N atropisomers with simultaneous creation of contiguous axial and central chirality by oxidative NHC (N-heterocyclic carbenes) catalyzed (3 + 3) cycloaddition. Using our method, we are able to synthesize structurally diverse N-N axially chiral pyrroles and indoles with vicinal central chirality or bearing a 2,3-dihydropyrimidin-4-one moiety in moderate to good yields and excellent enantioselectivities. Further synthetic transformations of the obtained axially chiral pyrroles and indoles derivative products are demonstrated. The reaction mechanism and the origin of enantioselectivity are understood through DFT calculations.

2.
Org Lett ; 26(3): 702-707, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38206074

RESUMO

We report herein an efficient NHC-catalyzed kinetic resolution of acyclic tertiary propargylic alcohols that provides them in high to excellent enantioselectivity. This is the first example of kinetic resolution realized by enantioselective acylation. The recovered enantioenriched alcohols can be facilely converted into other valuable compounds such as densely functionalized tertiary alcohols and carbmates in high yields and excellent stereopurity. Density functional theory calculations were performed to determine the reaction mechanism and to understand the origin of enantiodiscrimination.

4.
Trauma Violence Abuse ; 24(4): 2772-2788, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35993405

RESUMO

Child sexual abuse (CSA) has been recognized as a risk factor for sexual dysfunction and has attracted increasing attention. However, controversies remain regarding related research. The aim is to calculate the pooled effect size estimate for the correlation between CSA and sexual dysfunction in adults by meta-analysis. Five bibliographic databases (PubMed, Cochrane Library, Web of Science, Embase, and PsycINFO) were comprehensively searched to clarify the association between CSA and sexual dysfunction in adults. We used a fixed-effects model to determine the total pooled effect size estimate and reported odds ratios (ORs) and the corresponding 95% confidence intervals (CIs). Subgroup analysis, publication bias analysis, and sensitivity analysis were conducted. Adults who had a history of CSA experienced a higher proportion of sexual dysfunction than adults with no history of CSA (OR = 1.68, 95% CI [1.49, 1.87]). Subgroup analysis showed that women with a history of CSA reported a higher proportion of sexual dysfunction than men with a history of CSA (men: OR = 1.45, 95% CI [1.05, 1.84]; women: OR = 1.62, 95% CI [1.42, 1.83]). The estimates of the effect sizes differed substantially depending on the CSA and sexual dysfunction instruments that were used in each study and the region of each sample. This meta-analysis provides conclusive evidence of an association between CSA and sexual dysfunction in adults. Currently known interventions for the treatment of sexual dysfunction after CSA have only been evaluated in women, so specific interventions should be designed for men CSA survivors who experience sexual impairment.


Assuntos
Abuso Sexual na Infância , Maus-Tratos Infantis , Masculino , Criança , Humanos , Adulto , Feminino , Comportamento Sexual , Fatores de Risco , Sobreviventes
5.
Artigo em Inglês | MEDLINE | ID: mdl-36445604

RESUMO

Self-harm (SH) increases significantly in early adolescence with great variability, and childhood maltreatment (CM) contributes to this increase. Understanding the developmental pathway from CM to SH could provide clues for SH prevention. This study used latent class analysis (LCA) to detect the phenotype of SH and explored the role of psychological resilience in the pathway from the CM to SH phenotype among 5724 early adolescents (52.5% male). Three interpretable phenotypes of SH were identified: low SH (57.8%), medium SH (29.0%), and high SH (13.2%). Furthermore, CM was positively associated with the SH phenotype, psychological resilience mediated the association between CM and the SH phenotype (all ps < 0.001), and a larger mediating effect was observed in the medium SH (22.41%). Our findings offer new perspectives that improving psychological resilience can be used as an efficient intervention to reduce the risk of SH among early adolescents who have experienced CM.

6.
Adv Sci (Weinh) ; 9(35): e2105571, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36253092

RESUMO

The effectiveness of existing tissue-engineering cartilage (TEC) is known to be hampered by weak integration of biocompatibility, biodegradation, mechanical strength, and microenvironment supplies. The strategy of hydrogel-based TEC holds considerable promise in circumventing these problems. Herein, a non-toxic, biodegradable, and mechanically optimized double-network (DN) hydrogel consisting of polyethylene glycol (PEG) and kartogenin (KGN)-conjugated chitosan (CHI) is constructed using a simple soaking strategy. This PEG-CHI-KGN DN hydrogel possesses favorable architectures, suitable mechanics, remarkable cellular affinity, and sustained KGN release, which can facilitate the cartilage-specific genes expression and extracellular matrix secretion of peripheral blood-derived mesenchymal stem cells (PB-MSCs). Notably, after tracing the transplanted cells by detecting the rabbit sex-determining region Y-linked gene sequence, the allogeneic PB-MSCs are found to survive for even 3 months in the regenerated cartilage. Here, the long-term release of KGN is able to efficiently and persistently activate multiple genes and signaling pathways to promote the chondrogenesis, chondrocyte differentiation, and survival of PB-MSCs. Thus, the regenerated tissues exhibit well-matched histomorphology and biomechanical performance such as native cartilage. Consequently, it is believed this innovative work can expand the choice for developing the next generation of orthopedic implants in the loadbearing region of a living body.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Animais , Coelhos , Hidrogéis/metabolismo , Células-Tronco Mesenquimais/metabolismo , Cartilagem/metabolismo , Transplante de Células-Tronco , Polietilenoglicóis/metabolismo
7.
Asian J Androl ; 24(5): 549-557, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35915543

RESUMO

The incidence of infertility has recently risen. Semen quality is an important male fertility indicator, and dietary factors can affect semen quality. We conducted this systematic review and meta-analysis to determine the effects of healthy dietary patterns on semen quality. A literature search was conducted in 3 databases (Embase, Web of Science and PubMed) on August 21, 2021. The included cross-sectional studies examined the influence of the Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and prudent diet patterns on semen quality parameters; six studies (1244 subjects) were included. By comparing high consumption with low consumption of healthy dietary patterns, the results of the meta-analysis showed significantly higher sperm concentrations (mean difference [MD] = 6.88 × 106 ml-1, 95% confidence interval [CI]: 1.26 × 106 ml-1-12.49 × 106 ml-1; P < 0.05), a significant increase in total sperm count (MD = 16.70 × 106, 95% CI: 2.37 × 106-31.03 × 106; P < 0.05), and a significant increase in progressive sperm motility (MD = 5.85%, 95% CI: 2.59%-9.12%; P < 0.01). The sperm concentration, progressive sperm motility, and total sperm count were significantly higher in men with higher versus lower consumption of healthy dietary patterns. However, the results must be interpreted with caution.


Assuntos
Infertilidade Masculina , Análise do Sêmen , Estudos Transversais , Humanos , Masculino , Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides
8.
J Affect Disord ; 314: 249-252, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35878835

RESUMO

BACKGROUND: A strong link between childhood maltreatment (CM) and borderline personality features (BPF) has been consistently demonstrated. However, little is known about the role of psychological adjustment (PA) as a mediator of this relationship. The purpose of the study was to explore the mediating role of PA in the CM-BPF linkage in a large sample of early adolescents. METHODS: A total of 5724 students (mean age = 13.5, SD = 1.0) were recruited from three middle schools by using the multistage random cluster sampling method in Anhui Province, China. Participants were required to complete self-report questionnaires regarding CM experience, self-perceived PA and BPF. Mediation analyses were computed via structural equation modelling. RESULTS: CM victimization was positively associated with BPF, and individuals with lower levels of PA were more likely to present with BPF. Mediation analysis showed a significant indirect effect of CM on BPF via PA (effect = 0.047, 95 % CI: 0.035, 0.058). LIMITATION: The cross-sectional design of this study did not allow testing causality. The retrospective investigation of CM history could cause recall bias. CONCLUSIONS: PA partially mediates the relationship between CM and BPF. These findings have important implications for considering PA as a protective factor in this relationship.


Assuntos
Transtorno da Personalidade Borderline , Maus-Tratos Infantis , Adolescente , Transtorno da Personalidade Borderline/psicologia , Criança , Maus-Tratos Infantis/psicologia , Estudos Transversais , Ajustamento Emocional , Humanos , Estudos Retrospectivos
9.
Fa Yi Xue Za Zhi ; 38(1): 86-91, 2022 Feb 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-35725710

RESUMO

OBJECTIVES: To establish a diatom database by analyzing the quatity, species distribution and differences of diatom in water samples of the whole navigable sections of the Beijing-Hangzhou Grand Canal, to provide a reference for the inference of the drowning site. METHODS: Water samples were collected at 22 sites in the navigable sections of the Beijing-Hangzhou Grand Canal (Jining section to Yangzhou Section), and the diatoms at each site were qualitatively and quantitatively analyzed by using graphite digestion-scanning electron microscopy. RESULTS: Sampling site T (Laohuaijiang River Line, Gaoyou City, Yangzhou City, Jiangsu Province) had the highest number of diatoms, while sampling site O (Siyang County, Suqian City, Jiangsu Province) had the lowest number of diatoms, with a large gap of 68 times. At sampling site Q (Jiangpu District, Huaian city, Jiangsu Province), there were 19 species of diatoms. The sampling site O had the least diatoms, with 7 species. There were no significant differences in species evenness and species diversity at each sampling site (P>0.05). Some sampling sites have characterized diatoms, such as Caloneis at station A (Taibai Lake, Weishan County, Shandong Province), Rhoicosphenia at station B (Nanyang Town, Weishan County, Shandong Province), Amphora at station I (Taierzhuang District, Zaozhuang City, Shandong Province) and Epithemia at station J (Pizhou 310 national highway, Xuzhou City, Jiangsu Province). CONCLUSIONS: The species richness of diatoms gradually increased from north to south. Diatom species richness and species diversity might be higher in areas with complex environments and large population flow. Climate type has a certain influence on the distribution of diatoms.


Assuntos
Diatomáceas , Afogamento , Pequim , Humanos , Rios , Água
10.
Commun Biol ; 5(1): 237, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35301428

RESUMO

CRISPR-based genome engineering tools are associated with off-target effects that constitutively active Cas9 protein may instigate. Previous studies have revealed the feasibility of modulating Cas9-based genome- and base-editing tools using protein or small-molecule CRISPR inhibitors. Here we screened a set of small molecule compounds with irreversible warhead, aiming to identifying small-molecule modulators of CRISPR-Cas9. It was found that selective inhibitors of nuclear export (SINEs) could efficiently inhibit the cellular activity of Cas9 in the form of genome-, base- and prime-editing tools. Interestingly, SINEs did not function as direct inhibitors to Cas9, but modulated Cas9 activities by interfering with the nuclear export process of Cas9 mRNA. Thus, to the best of our knowledge, SINEs represent the first reported indirect, irreversible inhibitors of CRISPR-Cas9. Most importantly, an FDA-approved anticancer drug KPT330, along with other examined SINEs, could improve the specificities of CRISPR-Cas9-based genome- and base editing tools in human cells. Our study expands the toolbox of CRISPR modulating elements and provides a feasible approach to improving the specificity of CRISPR-Cas9-based genome engineering tools.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Transporte Ativo do Núcleo Celular , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
11.
Org Lett ; 22(22): 8894-8898, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33124830

RESUMO

Asymmetric synthesis of quinoline-naphthalene atropisomers with fully blocked ortho positions has been developed by a two-step strategy, which contains a chiral phosphoric acid-catalyzed Povarov reaction and a DDQ oxidation reaction. This method provides facile access to diverse functionalized quinoline-naphthalene atropisomers with one or two chiral axes in excellent yields (≤98%) and excellent enantioselectivities (≤99% ee).

12.
Thromb Res ; 188: 39-43, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32045773

RESUMO

BACKGROUND: Total knee arthroplasty (TKA) has been considered as an effective choice for end-stage osteoarthritis or rheumatic arthritis. Tranexamic acid (TXA) has been widely used to prevent excessive blood loss perioperatively. Similarly, hemocoagulase atrox can significantly diminish blood loss and transfusion requirements in surgeries, however, it was rarely used in TKA. The purpose of this study is to identify whether hemocoagulase atrox is equal to TXA in reducing blood loss and transfusion rates following TKA, and compare clinical outcomes and complications between the two groups. METHODS: 74 patients were randomized to receive TXA (1.5 g intra-articular combined with 1.5 g intravenous), or hemocoagulase atrox (1 U intra-articular combined with 1 U intravenous). The primary outcome was total blood loss. The secondary outcomes included reduction of hemoglobin concentration, clinical outcomes, blood coagulation values, thromboembolic complications, and transfusion rates. RESULTS: The mean total blood loss was 431.7 mL in the TXA group compared with 644.6 mL in the hemocoagulase atrox group, with statistical significance (P < 0.05). There were significant differences in reduction of hemoglobin level (P < 0.05). The rate of deep vein thrombosis (DVT) in patients given TXA was higher than those given hemocoagulase atrox, however, there were no significant differences. No transfusions were required in either group, and no significant differences were found in the length of hospital stay and clinical outcomes. CONCLUSIONS: Although the blood loss was significantly greater in the hemocoagulase atrox group, no transfusions were required and no significant differences were observed for any other outcomes measured. Meanwhile, the rate of DVT in the hemocoagulase atrox group tends to be lower than those in TXA group. We concluded that hemocoagulase atrox was not superior to TXA in reducing perioperative blood loss. Further studies are warranted to evaluate if hemocoagulase atrox use could improve perioperative blood loss in patients with high thrombotic risk undergoing TKA.


Assuntos
Antifibrinolíticos , Artroplastia do Joelho , Ácido Tranexâmico , Administração Intravenosa , Antifibrinolíticos/uso terapêutico , Artroplastia do Joelho/efeitos adversos , Batroxobina , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue , Humanos , Ácido Tranexâmico/uso terapêutico
13.
Genome Biol ; 21(1): 51, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32102684

RESUMO

BACKGROUND: CRISPR-Cas9 has been developed as a therapeutic agent for various infectious and genetic diseases. In many clinically relevant applications, constitutively active CRISPR-Cas9 is delivered into human cells without a temporal control system. Excessive and prolonged expression of CRISPR-Cas9 can lead to elevated off-target cleavage. The need for modulating CRISPR-Cas9 activity over time and dose has created the demand of developing CRISPR-Cas off switches. Protein and small molecule-based CRISPR-Cas inhibitors have been reported in previous studies. RESULTS: We report the discovery of Cas9-inhibiting peptides from inoviridae bacteriophages. These peptides, derived from the periplasmic domain of phage major coat protein G8P (G8PPD), can inhibit the in vitro activity of Streptococcus pyogenes Cas9 (SpCas9) proteins in an allosteric manner. Importantly, the inhibitory activity of G8PPD on SpCas9 is dependent on the order of guide RNA addition. Ectopic expression of full-length G8P (G8PFL) or G8PPD in human cells can inactivate the genome-editing activity of SpyCas9 with minimum alterations of the mutation patterns. Furthermore, unlike the anti-CRISPR protein AcrII4A that completely abolishes the cellular activity of CRISPR-Cas9, G8P co-transfection can reduce the off-target activity of co-transfected SpCas9 while retaining its on-target activity. CONCLUSION: G8Ps discovered in the current study represent the first anti-CRISPR peptides that can allosterically inactivate CRISPR-Cas9. This finding may provide insights into developing next-generation CRISPR-Cas inhibitors for precision genome engineering.


Assuntos
Proteína 9 Associada à CRISPR/antagonistas & inibidores , Sistemas CRISPR-Cas , Fragmentos de Peptídeos/metabolismo , Regulação Alostérica , Bacteriófago M13 , Proteína 9 Associada à CRISPR/metabolismo , Proteínas do Capsídeo/química , Edição de Genes/métodos , Células HEK293 , Humanos , Células K562 , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética
14.
Front Chem ; 7: 677, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681730

RESUMO

To provide a vehicle for sustained release of cartilage-protective agent for the potential application of osteoarthritis (OA) treatment, we developed a kartogenin (KGN)-incorporated thermogel for intra-articular injection. We fabricated a poly(lactide-co-glycolide)-block-poly(ethylene glycol)-block-poly(lactide-co-glycolide) (PLGA-PEG-PLGA) thermogel as a KGN carrier for IA injection. OA chondrocytes were cultured in thermogel with or with no KGN to investigate the effect of KGN thermogel on cartilage matrix. The in vivo effect of KGN thermogel on OA was examined in a rabbit OA model. The KGN thermogel showed a sustained in vitro release of KGN for 3 weeks. OA chondrocytes proliferated well both in thermogel and KGN thermogel. In addition, OA chondrocytes produced higher amount of [type 2 collagen (COL-2) and glycosaminoglycan (GAG)], as well as lower level of matrix metalloproteinase 13 (MMP-13) in KGN thermogel that those in thermogel with no addition of KGN. The gene analysis supported that KGN thermogel enhanced expression of hyaline-cartilage specific genes Col 2 and AGC, and inhibited the expression of MMP-13. Compared with intra-articular injection of saline or thermogel containing no KGN, KGN thermogel can enhance cartilage regeneration and inhibit joint inflammation of arthritic knees in a rabbit ACLT-induced OA model at 3 weeks after the injection. Therefore, the KGN-incorporated PLGA-PEG-PLGA thermogel may provide a novel treatment modality for OA treatment with IA injection.

15.
Adv Mater ; 31(49): e1904341, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31621958

RESUMO

Current approaches to fabrication of nSC composites for bone tissue engineering (BTE) have limited capacity to achieve uniform surface functionalization while replicating the complex architecture and bioactivity of native bone, compromising application of these nanocomposites for in situ bone regeneration. A robust biosilicification strategy is reported to impart a uniform and stable osteoinductive surface to porous collagen scaffolds. The resultant nSC composites possess a native-bone-like porous structure and a nanosilica coating. The osteoinductivity of the nSC scaffolds is strongly dependent on the surface roughness and silicon content in the silica coating. Notably, without the use of exogenous cells and growth factors (GFs), the nSC scaffolds induce successful repair of a critical-sized calvarium defect in a rabbit model. It is revealed that topographic and chemical cues presented by nSC scaffolds could synergistically activate multiple signaling pathways related to mesenchymal stem cell recruitment and bone regeneration. Thus, this facile surface biosilicification approach could be valuable by enabling production of BTE scaffolds with large sizes, complex porous structures, and varied osteoinductivity. The nanosilica-functionalized scaffolds can be implanted via a cell/GF-free, one-step surgery for in situ bone regeneration, thus demonstrating high potential for clinical translation in treatment of massive bone defects.


Assuntos
Regeneração Óssea , Colágeno/química , Nanoestruturas/química , Dióxido de Silício/química , Alicerces Teciduais/química , Animais , Materiais Biomiméticos/química , Biomimética , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Células-Tronco Mesenquimais/citologia , Nanoestruturas/ultraestrutura , Osteogênese , Porosidade , Coelhos , Crânio/lesões , Crânio/fisiologia
16.
Artigo em Chinês | MEDLINE | ID: mdl-31245954

RESUMO

OBJECTIVE: To observe the effects of AdipoRon orally on the functions of spleen and pancreas in type 2 diabetic mice, in order to present data for clinical application. METHODS: Forty C57/BL6 male mice were randomly divided into 2 groups: normal control group (n=10) and model group (n=30), the former group was fed normally, while the later group was fed with high fat and sugar for 4 weeks.After that, type 2 diabetes model was established in DM group induced by intraperitoneal injection of streptozotocin (STZ, 40 mg/kg).As type 2 diabetes model established successfully, the model mice were randomly divided into three groups (n=10): diabetes mellitus (DM) group, high dose of AdipoRon group (DM + H) and low dose of adiponRon group (DM + L).All the four groups were treated with saline, saline, AdipoRon at the doses of 20 mg/kg and 50 mg/kg by gavages respectively, once a day for 10 days.And then put them to death for collecting blood, pancreas and spleen.Pathological changes of pancreas were observed with a light microscope after HE staining.Protein contents of insulin receptor (INSR), insulin receptor substrate 1( IRS-1) and tumor necrosis factor-α(TNF-α) in pancreatic and spleen tissues were detected by ELISA.The protein level of phosphorylation insulin receptor substrate 1(p-IRS-1) in pancreas was determined by Western blot, and the expression of insulin mRNA in pancreas was tested by RT-PCR. RESULTS: Under the light microscope, it was visible that the pancreatic tissue in NC group was full and closely packed, and the islet was big.Pancreatic tissue of DM mice was incompact and the islet of DM mice was smaller than that of normal mice.As for the mice treated with AdipoRon orally, the pancreatic tissue was full and closely arranged, and the islet was slightly smaller.Compared with NC group, the levels of TNF-α in pancreas and spleen of DM group were increased markedly, the levels of INSR and IRS-1 were decreased, the spleen coefficient, p-IR-1 protein level and insulin mRNA expression in pancreas were decreased, all were significant statistically (P<0.05).Compared with DM group, the levels of TNF-α in pancreas and spleen of AdipoRon groups were decreased, the levels of INSR and IRS-1 in pancreas and spleen of AdipoRon groups were increased, while the spleen coefficient was increased (P<0.05).The p-IRS-1 protein level and insulin mRNA expression in pancreas in DM+H group were increased (P<0.05).Compared with DM + L group, the level of TNF-α was decreased, and the levels of INSR and IRS-1 were significantly increased (P<0.05) in DM + H group (P<0.05). CONCLUSION: Oral administration of AdipoRon can protect the spleen and pancreas of diabetic mice by decreasing the inflammatory response, up-regulating the expression of INSR, and increasing p-IRS-1 level in diabetic mice.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Piperidinas , Baço , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inflamação , Insulina , Proteínas Substratos do Receptor de Insulina/efeitos dos fármacos , Masculino , Camundongos , Pâncreas , Piperidinas/farmacologia , Distribuição Aleatória , Receptor de Insulina/efeitos dos fármacos , Baço/efeitos dos fármacos
17.
Sci Transl Med ; 11(487)2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30971451

RESUMO

Reconstruction of the anisotropic structure and proper function of the knee meniscus remains an important challenge to overcome, because the complexity of the zonal tissue organization in the meniscus has important roles in load bearing and shock absorption. Current tissue engineering solutions for meniscus reconstruction have failed to achieve and maintain the proper function in vivo because they have generated homogeneous tissues, leading to long-term joint degeneration. To address this challenge, we applied biomechanical and biochemical stimuli to mesenchymal stem cells seeded into a biomimetic scaffold to induce spatial regulation of fibrochondrocyte differentiation, resulting in physiological anisotropy in the engineered meniscus. Using a customized dynamic tension-compression loading system in conjunction with two growth factors, we induced zonal, layer-specific expression of type I and type II collagens with similar structure and function to those present in the native meniscus tissue. Engineered meniscus demonstrated long-term chondroprotection of the knee joint in a rabbit model. This study simultaneously applied biomechanical, biochemical, and structural cues to achieve anisotropic reconstruction of the meniscus, demonstrating the utility of anisotropic engineered meniscus for long-term knee chondroprotection in vivo.


Assuntos
Menisco/anatomia & histologia , Menisco/fisiologia , Engenharia Tecidual , Animais , Anisotropia , Fenômenos Biomecânicos , Cartilagem/patologia , Diferenciação Celular , Condrócitos/citologia , Análise de Elementos Finitos , Regulação da Expressão Gênica , Articulações/patologia , Masculino , Coelhos , Regeneração , Alicerces Teciduais/química
18.
J Am Chem Soc ; 140(38): 11911-11915, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30215257

RESUMO

Direct polymerization of allyl alcohol generally results in low molar mass oligomers or highly branched or cross-linked structures, and the properties and applications of linear, high molar mass poly(allyl alcohol) (PAA) are relatively unexplored. Such macromolecular materials that cannot otherwise be obtained directly can be accessed by postpolymerization modification strategies. Herein we describe the synthesis and characterization of linear, high molar mass PAA by borohydride reduction of a new activated polyacrylamide. The facile polymerization and mild reduction conditions enable the preparation of PAA of targeted molar masses and low dispersity, as well as PAA block polymers via chemoselective reduction of the activated amide moiety.

19.
Sci Rep ; 8(1): 9041, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29899552

RESUMO

Meniscal allograft transplantation yields good and excellent results but is limited by donor availability. The purpose of the study was to evaluate the effectiveness of radiated deep-frozen xenogenic meniscal tissue (RDF-X) as an alternative graft choice in meniscal transplantation. The xenogenic meniscal tissues were harvested from the inner 1/3 part of the porcine meniscus and then irradiated and deeply frozen. The medial menisci of rabbits were replaced by the RDF-X. Meniscal allograft transplantation, meniscectomy and sham operation served as controls. Only a particular kind of rabbit-anti-pig antibody (molecular ranging 60-80 kD) was detected in the blood serum at week 2. The menisci of the group RDF-X grossly resembled the native tissue and the allograft meniscus with fibrocartilage regeneration at postoperative 1 year. Cell incorporation and the extracellular matrix were mostly observed at the surface and the inner 1/3 part of the newly regenerated RDF-X, which was different from the allograft. The biomechanical properties of the group RDF-X were also approximate to those of the native meniscus except for the compressive creep. In addition, chondroprotection was achieved after the RDF-X transplantation although the joint degeneration was not completely prevented. To conclude, the RDF-X could be a promising alternative for meniscal transplantation with similar tissue regeneration capacity to allograft transplantation and superior chondroprotection. The potential minor immunological rejection should be further studied before its clinical application.


Assuntos
Meniscos Tibiais/cirurgia , Menisco/transplante , Regeneração , Membrana Sinovial/fisiopatologia , Animais , Cartilagem Articular/fisiopatologia , Cartilagem Articular/cirurgia , Criopreservação/métodos , Humanos , Meniscos Tibiais/fisiopatologia , Menisco/ultraestrutura , Microscopia Eletrônica de Varredura , Coelhos , Suínos , Transplante Heterólogo
20.
J Thromb Thrombolysis ; 46(3): 275-282, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29948755

RESUMO

Endothelial nitric oxide synthase (eNOS) encoded by nitric oxide synthase 3 (NOS3), can generate nitric oxide (NO) which serves as an important deterrent to the pathogenesis of thrombosis by modulating the activation, adhesion and aggregate formation of platelets. Three serum miRNAs (miR-195, miR-532 and miR-582) have been suggested as biomarkers for the diagnosis of deep vein thrombosis (DVT), however their potential roles in DVT is not clear. The effect of miRNAs inhibiting the expression of NOS3 was evaluated in vitro. miR-195, miR-532 and miR-582 mimic, inhibitor, and control miRNAs were transfected into endothelial cells. The roles of miR-195, miR-532 and miR-582 regulating the expression of eNOS were evaluated by real-time quantitative PCR, Western Blotting and luciferase reporter assays. NO release was measured by Griess method. We confirmed NOS3 as a direct target of miR-195 and miR-582, which binds to the 3'-UTR of NOS3 mRNA in endothelial cells. A significantly inverse correlation between these two miRNAs and eNOS expression was detected. NO release from endothelial cells was decreased when the expression level of miR-195 and miR-582 was up-regulated. These findings indicated that miR-195 and miR-582 regulated NO release by targeting 3'-UTR of NOS3 post-transcriptionally in endothelial cells. Therefore, miR-195 and miR-582 might play an important role in maintaining endothelial NO bioavailability and could be a novel target for treatment of thrombotic diseases.


Assuntos
Células Endoteliais/metabolismo , MicroRNAs/fisiologia , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Óxido Nítrico/metabolismo , Regiões 3' não Traduzidas , Sítios de Ligação , Células Cultivadas , Células Endoteliais/enzimologia , Humanos , MicroRNAs/genética , MicroRNAs/farmacologia , Óxido Nítrico/análise , Transfecção
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