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1.
J Nanosci Nanotechnol ; 20(4): 2598-2602, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492282

RESUMO

AlN nanowires macro-array were successfully fabricated on Si substrate by double template method and chemical vapour deposition. The research shows that AlN nanowires array with different diameter, length and coverage can be prepared by controlling the experimental conditions. The as-prepared AlN nanowires array were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Furthermore, the Ultraviolet absorption of AlN nanowires array as a sensors was investigated and calculated with the first principle.

2.
Carbohydr Polym ; 227: 115343, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590883

RESUMO

Porous poly(L-lactic acid) (PLLA) nanofibrous membrane with the high surface area was developed by electrospinning and post acetone treatment and used as a substrate for deposition of chitosan. Chitosan was coated onto porous nanofibrous membrane via direct immersion coating method. The porous PLLA/chitosan structure provided chitosan a high surface framework to fully and effectively adsorb heavy metal ions from water and showed higher and faster ion adsorption. The composite membrane was used to eliminate copper ions from aqueous solutions. Chitosan acts as an adsorbent due to the presence of aminic and hydroxide groups which are operating sites for the capture of copper ions. The maximum adsorption capacity of copper ions reached 111.66 ± 3.22 mg/g at pH (7), interaction time (10 min) and temperature (25 °C). The adsorption kinetics of copper ions was established and was well agreed with the second-order model and Langmuir isotherm. Finally, the thermodynamic parameters were studied.

3.
Front Biosci (Landmark Ed) ; 25: 480-497, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585898

RESUMO

Acute lung injury (ALI) is a life-threatening condition caused by severe inflammation of lung tissues. We hypothesized that lipopolysaccharide induced acute lung inflammation and injury in mice might be controlled by lonicerin (LCR), a plant flavonoid that impacts immunity, oxidative stress, and cell proliferation. LCR reduced pathological changes including pulmonary edema, elevation of protein in bronchoalveolar lavage, inflammation, pro-inflammatory gene expression, expression of toll-like receptor 4/nuclear factor-kappa B, apoptosis, and significantly reduced mortality. Together, the results suggest that LCR might be a potential and effective candidate for the treatment of ALI that acts by inhibiting inflammation and apoptosis.

4.
Chemosphere ; 240: 124936, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31568941

RESUMO

Triphenyltin (TPT) is widely used and commonly found in a water environment, so its effects on aquatic systems are of great concern. This study aimed to reveal the effects of chronic parental exposure of TPT on thyroid disruption and growth inhibition in zebrafish. Adult zebrafish (F0 generation) were exposed to environmentally relevant concentrations (1, 10, and 100 ng/L) of TPT for 60 days, and the larvae (F1 generation) were tested without TPT treatment. Results demonstrated that parental exposure to TPT disrupts thyroid function in zebrafish offspring: serum thyroxine (T4) significantly decreased, while serum 3,5,3'-triiodothyronine (T3) increased, and several genes involved in the hypothalamic-pituitary-thyroid (HPT) axis were down-regulated. In addition, we observed developmental abnormalities in the larvae, demonstrated by a significantly altered hatching rate, malformation rate, body length, heart rate, and survival rate, as well as down-regulation of genes involved in the growth hormone/insulin-like growth factor (GH/IGF) axis. Therefore, parental exposure to TPT induces toxicity in fish offspring through perturbation of the HPT and GH/IGF axes.

5.
Mikrochim Acta ; 186(11): 732, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667627

RESUMO

The authors describe an electrochemical and an optical method for the determination of As(V) by using iron oxyhydroxide (FeOOH) nanorods that display peroxidase-mimicking activity. The nanorods catalyze the oxidation of substrate ABTS by H2O2 to form a green product with an absorption maximum at 418 nm. If, however, As(V) is electrostatically adsorbed on the nanorods, the oxidation is gradually inhibited. A colorimetric assay was worked out based on these findings. Response is linear in the 0 to 8 ppb and 8 to 200 ppb As(V) concentration range, and the detection limit is 0.1 ppb. Even higher sensitivity is achieved in an electrochemical method which is based on the excellent electrical conductivity of FeOOH nanorods. Electrochemical analysis of As(V) was achieved by first adsorbing As(V) on the nanorods. This inhibits the ABTS reduction current signal, best measured at a potential of 150 mV (vs. Ag/AgCl). The linear range extends from 0.04 to 200 ppb, and the detection limit is as low as 12 ppt. Graphical abstract Schematic representation of FeOOH nanorod-based colorimetric and electrochemical assays for arsenate (As(V)). As(V) adsorbed on FeOOH nanorods inhibits the peroxidase-mimicking activity of nanorods, and a colorimetric and electrochemical dual-signal assay was constructed to achieve sensitive determination of As(V).

6.
J Cell Biochem ; 2019 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-31680311

RESUMO

The dysregulation of long noncoding (lncRNA) UCA1 may play an important role in tumor progression. However, the function in gliomas is unclear. Therefore, this experiment was designed to explore the pathogenesis of glioma based on lncRNA UCA1. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of lncRNA UCA1, miR-135a, and HOXD9 in gliomas tissues. The effect of lncRNA UCA1 and miR-135a on tumor cell proliferation and migration invasiveness was examined by CCK-8 and transwell assays. Target gene prediction and screening, luciferase reporter assay were used to verify downstream target genes of lncRNA UCA1. Expression of E-cadherin, N-cadherin, vimentin, and HOXD9 was detected by RT-qPCR and Western blotting. The tumor changes in mice were detected by in vivo experiments in nude mice. lncRNA UCA1 was highly expressed in glioma tissues and cell lines. lncRNA UCA1 expression was associated with significantly poor overall survival in gliomas. Moreover, lncRNA UCA1 significantly enhanced cell proliferation and migration, and promoted the occurrence of EMT. In addition, lncRNA UCA1 promoted the development of EMT by positively regulating HOXD9 expression as a miR-135a sponge. In vivo experiments indicated that UCA1 exerted its biological functions by modulating miR-135a and HOXD9. In conclusion, lncRNA UCA1 can induce the activation of HOXD9 by inhibiting the expression of miR-135a and promote the occurrence of EMT in glioma.

7.
J Cell Physiol ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31691974

RESUMO

Inflammation is considered to be critical in the pterygium progression and recurrence. However, the underlying molecular mechanism is not well understood. Herein, we investigated the potential role of RNA binding protein human antigen R (HuR) responsible for the impact of inflammation on pterygium development. The expression of HuR and matrix metallopeptidase-9 (MMP-9) in pterygium and normal conjunctiva was detected with immunohistochemistry and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The influence of interleukin-1ß (IL-1ß) on HuR expression and cellular distribution was determined with western blot and immunofluorescence. The pterygium fibroblast (PTF) migration was determined with scratch wound healing assay and Transwell migration assay. MMP-9 production was determined with qRT-PCR and gelatin zymography. The interaction between HuR and MMP-9 was investigated with RNP immunoprecipitation (IP) followed by RT-PCR and messenger RNA (mRNA) stability analysis. HuR and MMP-9 expression are elevated in pterygium, especially progressive pterygium compared with normal conjunctiva. IL-1ß could increase the expression and nucleus-cytoplasm shuttle of HuR in cultured PTFs. HuR mediated the stimulatory effect of IL-1ß on PTF migration and MMP-9 production. HuR bound to MMP-9 mRNA and in turn increased it stability. Our results suggest that posttranscriptional regulation of MMP-9 via stabilizing mRNA by HuR might contribute to the stimulatory effect of inflammatory factor IL-1ß on pterygium progression. These findings shed light on the pathogenesis of pterygium and provide a promising target for adjuvant treatment of pterygium.

8.
Appl Opt ; 58(27): 7375-7378, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674386

RESUMO

In this paper, an integrated processing method was demonstrated to fabricate the polymer-based thermo-optic (TO) switch with low power consumption. The characteristic parameters of the switch were carefully designed and simulated. The air trench structure was exploited to reduce the power consumption, which can be formed with the waveguide simultaneously by the integrated processing method. Moreover, the introduced polymer/silica hybrid waveguide structure can also improve the response time of the device. A typical fabricated switch presented a low switching power of 5.2 mW. The measured switching rise time and fall time are 192.2 and 201.1 µs, respectively.

9.
Pharmazie ; 74(10): 601-605, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31685085

RESUMO

Atherosclerosis (AS) is characterized by the significant accumulation of low-density lipoprotein (LDL)-cholesterol in macrophages that reside in the vessel wall and the resultant inflammatory response. Therefore, inhibition of LDL-induced inflammation is a promising interference for AS. Many traditional Chinese medicine prescriptions have been developed for AS treatment. Geniposide (GEN) is an iridoid glycoside mainly found in Gardenia jasminoides fruit. Although GEN has previously been shown to possess anti-atherosclerotic activities, its effects on the formation of macrophage-derived foam cells remain poorly characterized. In our current study, we demonstrated that GEN could significantly inhibit oxidized light-density lipoprotein (ox-LDL) induced macrophage foam cell formation and the expression of pro-inflammatory cytokines in a dose-dependent manner. In addition, treatment of GEN in bone-marrow derived macrophages repressed iNOS expression and NO expression. GEN could also alleviate ox-LDL-dependent up-regulation of CD36 expression by blocking the phosphorylation of p38 MAPK, ERK, JNK and NF-kB p65. The results of our current study demonstrate that GEN exhibits significant therapeutic effects against ox-LDA-induced foam cell formation and inflammation. Therefore, GEN is promising agent for treating AS.

10.
Acta Trop ; : 105237, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31669530

RESUMO

Theileria annulata schizont transformed bovine lymphocytes show the feature of permanent proliferation in in vitro culture. In this study, we optimized a suitable culture medium for transformed cells to ensure a high yield of quality cells in suspension culture. As the basis for the optimized medium, we combined 75% Gibco (GB) and 25% RPMI-1640 medium. Glucose, lactic acid, ammonia, growth factors and several kinds of amino acids at specific concentrations play important roles in maintaining the maximum growth rate and the quality of cells. The metabolic flow of 17 amino acids, glucose and nutrients was determined with high-performance liquid chromatography (HPLC) and cell viability analysis. The genetic stability of the TaSP and TaSE genes at different passages of the cell line in suspension culture was determined using PCR amplification. The optimal concentrations or tolerated levels of glucose, lactic acid and ammonia were 10-14, 2-5.5 and 3.5-5.5 mmol/L, respectively. Our data demonstrated that the potential utility of the medium optimized here to yield high quality cells compared with basal (normally used) medium. The medium also facilitated the easy maintenance of transformed cells with high yields and excellent quality for in vitro studies. This study also provides insight into the processes of optimization and vaccine development.

11.
Cancer Commun (Lond) ; 39(1): 75, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730020

RESUMO

BACKGROUND: The National Comprehensive Cancer Network guidelines recommend intensity-modulated radiotherapy (IMRT) as the primary curative treatment for newly diagnosed nasopharyngeal carcinoma (NPC), but the radiation-related complications and relatively high medical costs remain a consequential burden for the patients. Endoscopic nasopharyngectomy (ENPG) was successfully applied in recurrent NPC with radiation free and relatively low medical costs. In this study, we examined whether ENPG could be an effective treatment for localized stage I NPC. METHODS: Ten newly diagnosed localized stage I NPC patients voluntarily received ENPG alone from June 2007 to September 2017 in Sun Yat-sen University Cancer Center. Simultaneously, the data of 329 stage I NPC patients treated with IMRT were collected and used as a reference cohort. The survival outcomes, quality of life (QOL), and medical costs between two groups were compared. RESULTS: After a median follow-up of 59.0 months (95% CI 53.4-64.6), no death, locoregional recurrence, or distant metastasis was observed in the 10 patients treated with ENPG. The 5-year overall survival, local relapse-free survival, regional relapse-free survival, and distant metastasis-free survival among the ENPG-treated patients was similar to that among the IMRT-treated patients (100% vs. 99.1%, 100% vs. 97.7%, 100% vs. 99.0%, 100% vs. 97.4%, respectively, P > 0.05). In addition, compared with IMRT, ENPG was associated with decreased total medical costs ($ 4090.42 ± 1502.65 vs. $ 12620.88 ± 4242.65, P < 0.001) and improved QOL scores including dry mouth (3.3 ± 10.5 vs. 34.4 ± 25.8, P < 0.001) and sticky saliva (3.3 ± 10.5 vs. 32.6 ± 23.3, P < 0.001). CONCLUSIONS: ENPG alone was associated with promising long-term survival outcomes, low medical costs, and satisfactory QOL and might therefore be an alternative strategy for treating newly diagnosed localized stage I NPC patients who refused radiotherapy. However, the application of ENPG should be prudent, and prospective clinical trials were needed to further verify the results.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31730031

RESUMO

Strain ICH-3T, isolated from a freshwater pond in Taiwan 9ROC), was characterized using a polyphasic taxonomy approach. Phylogenetic analyses based on 16S rRNA gene sequences and an up-to-date bacterial core gene set (92 protein clusters) indicated that ICH-3T is affiliated with the species in the genus Rubrivivax. ICH-3T was most closely related to Rubrivivax benzoatilyticus JA2T and Rubrivivax gelatinosus NCIB 8290T with 97.5 and 97.4 % 16S rRNA gene sequence similarity. The average nucleotide identity and digital DNA-DNA hybridization identity between ICH-3T and the two closely related strains were 77.3 and 20.9-21.0 %, respectively, indicating that ICH-3T represents a novel species of the genus Rubrivivax. Cells were Gram-stain-negative, aerobic, non-motile, rod-shaped and formed white colonies. Optimal growth occurred at 30 °C, pH 7.5-8.0 and with 0.5 % NaCl. The major fatty acids (>20 %) of ICH-3T were summed feature 3 (comprising C16  :  1ω7c and/or C16  :  1ω6c) and C16  :  0. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an uncharacterized aminophospholipid and two uncharacterized phospholipids. The major isoprenoid quinone was Q-8. The genomic DNA G+C content of ICH-3T was 70.3 mol%. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain ICH-3T should be classified as representing a novel species of the genus Rubrivivax, for which the name Rubrivivax albus sp. nov. is proposed. The type strain is ICH-3T (=BCRC 81155T=LMG 30930T=KCTC 62866T).

13.
Theranostics ; 9(25): 7648-7665, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695792

RESUMO

Alternative splicing (AS) has emerged as a key event in tumor development and microenvironment formation. However, comprehensive analysis of AS and its clinical significance in head and neck squamous cell carcinoma (HNSC) is urgently required. Methods: Genome-wide profiling of AS events using RNA-Seq data from The Cancer Genome Atlas (TCGA) program was performed in a cohort of 464 patients with HNSC. Cancer-associated AS events (CASEs) were identified between paired HNSC and adjacent normal tissues and evaluated in functional enrichment analysis. Splicing networks and prognostic models were constructed using bioinformatics tools. Unsupervised clustering of the CASEs identified was conducted and associations with clinical, molecular and immune features were analyzed. Results: We detected a total of 32,309 AS events and identified 473 CASEs in HNSC; among these, 91 were validated in an independent cohort (n = 15). Functional protein domains were frequently altered, especially by CASEs affecting cancer drivers, such as PCSK5. CASE parent genes were significantly enriched in pathways related to HNSC and the tumor immune microenvironment, such as the viral carcinogenesis (FDR < 0.001), Human Papillomavirus infection (FDR < 0.001), chemokine (FDR < 0.001) and T cell receptor (FDR < 0.001) signaling pathways. CASEs enriched in immune-related pathways were closely associated with immune cell infiltration and cytolytic activity. AS regulatory networks suggested a significant association between splicing factor (SF) expression and CASEs and might be regulated by SF methylation. Eighteen CASEs were identified as independent prognostic factors for overall and disease-free survival. Unsupervised clustering analysis revealed distinct correlations between AS-based clusters and prognosis, molecular characteristics and immune features. Immunogenic features and immune subgroups cooperatively depict the immune features of AS-based clusters. Conclusion: This comprehensive genome-wide analysis of the AS landscape in HNSC revealed novel AS events related to carcinogenesis and immune microenvironment, with implications for prognosis and therapeutic responses.

14.
Math Biosci Eng ; 16(6): 7155-7176, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31698608

RESUMO

Modal identification involves primarily the determination of natural frequencies, damping ratios, mode shapes of a dynamic system, etc. It is usually regarded as an essential task in a wide branch of structural dynamics and civil engineering, such as structural vibration control and damage identification of buildings or bridges. There are many modal identification techniques. Basically, these techniques can be categorized into two groups: deterministic methods and Bayesian approaches. The first group can be used to provide deterministic (or optimal) estimations of modal parameters, but they are unable to quantify the estimation uncertainties. The second group is based on a usage of the Bayesian framework. Compared to the first group, the second group of methods has a typical merit of being able to offer uncertainty information of identified parameters, which is of great interests, or even necessary, for some follow-up studies. In this paper, both a deterministic method, i.e., a combination of spectral analysis, filtering and Random Decrement Technique (RDT), and a Bayesian method, i.e., Bayesian Spectral Density Approach (BSDA), are exploited to experimentally identify the modal parameters of a 303 m high-rise building that was subjected to a landfall typhoon. The validity and efficiency of each method is verified by comparing the two kinds of results. Meanwhile, the identified modal parameters are used for the serviceability assessment of this high-rise building against some frequency-specific criteria.

15.
Curr Top Med Chem ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31721704

RESUMO

BACKGROUND: Breast plastic surgery is a rapidly evolving field in medicine. The modern view of surgical trends reflects the desire to minimize complications and introduce advanced technologies. These always will be priorities for surgeons. Reconstructive surgery, a branch of plastic surgery focusing on restoration of lost functional and aesthetic component, seeks to enhance psychological rehabilitation and improve quality of life, as well as aesthetic recovery. OBJECTIVE: This review addresses the action of fibrin agents and their effect on the quality of surgical hemostasis. DISCUSSION AND CONCLUSION: The fundamental goals for the surgeon are to perform a minimally traumatic intervention and to prevent any form of complication. Achieving complete hemostasis is an intraoperative necessity. Timely prevention of bleeding and hemorrhagic phenomena can affect not only the outcome of the operation, but also the incidence of postoperative complications. Topics include the integrity of microvascular anastomoses, tissue adhesion, and the incidence of seromas and hematomas associated with fibrin glue usage. The literature on fibrin adhesives with respect to prevention of postoperative complications, and the effectiveness with active drainage also are analyzed.

16.
Parasit Vectors ; 12(1): 542, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31727141

RESUMO

BACKGROUND: Larvae of Echinococcus granulosus (sensu lato) dwell in host organs for a long time but elicit only a mild inflammatory response, which indicates that the resolution of host inflammation is necessary for parasite survival. The recruitment of alternatively activated macrophages (AAMs) has been observed in a variety of helminth infections, and emerging evidence indicates that AAMs are critical for the resolution of inflammation. However, whether AAMs can be induced by E. granulosus (s.l.) infection or thioredoxin peroxidase (TPx), one of the important molecules secreted by the parasite, remains unclear. METHODS: The activation status of peritoneal macrophages (PMs) derived from mice infected with E. granulosus (sensu stricto) was analyzed by evaluating the expression of phenotypic markers. PMs were then treated in vivo and in vitro with recombinant EgTPx (rEgTPx) and its variant (rvEgTPx) in combination with parasite excretory-secretory (ES) products, and the resulting activation of the PMs was evaluated by flow cytometry and real-time PCR. The phosphorylation levels of various molecules in the PI3K/AKT/mTOR pathway after parasite infection and antigen stimulation were also detected. RESULTS: The expression of AAM-related genes in PMs was preferentially induced after E. granulosus (s.s.) infection, and phenotypic differences in cell morphology were detected between PMs isolated from E. granulosus (s.s.)-infected mice and control mice. The administration of parasite ES products or rEgTPx induced the recruitment of AAMs to the peritoneum and a notable skewing of the ratio of PM subsets, and these effects are consistent with those obtained after E. granulosus (s.s.) infection. ES products or rEgTPx also induced PMs toward an AAM phenotype in vitro. Interestingly, this immunomodulatory property of rEgTPx was dependent on its antioxidant activity. In addition, the PI3K/AKT/mTOR pathway was activated after parasite infection and antigen stimulation, and the activation of this pathway was suppressed by pre-treatment with an AKT/mTOR inhibitor. CONCLUSIONS: This study demonstrates that E. granulosus (s.s.) infection and ES products, including EgTPx, can induce PM recruitment and alternative activation, at least in part, via the PI3K/AKT/mTOR pathway. These results suggest that EgTPx-induced AAMs might play a key role in the resolution of inflammation and thereby favour the establishment of hydatid cysts in the host.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31727364

RESUMO

Laccases (benzenediol: oxygen oxidoreductases, EC1.10.3.2) can oxidize various substrates, and those which are tolerant to and even activated by salts have attracted a lot of attention due to their application potential in certain industries. The mechanism of the salt activation of laccases is awaiting to be elucidated yet. Our previous study (Li, Xie et al. 2018) supposed that the salt activation of marine laccase Lac15 might be attributed to Cl- ion specifically binding to some local sites to interfere substrate binding and/or electron transfer. In this study, we found two sites whose mutations resulted in elimination of the salt activation of Lac15's activity towards catechol and dopamine respectively, and revealed that the mutations affected the activity by altering both Em and kcat, demonstrating the supposed mechanism. A model for the salt activation of laccases was accordingly proposed, albeit some details are to be elucidated.

18.
Parasit Vectors ; 12(1): 523, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694676

RESUMO

BACKGROUND: Bovine babesiosis is caused by protozoan parasites of the genus Babesia and presents a wide spectrum of clinical manifestations. Disease severity depends on the type of Babesia species infection. Generally, B. bovis and B. bigemina are considered as the causative agents of bovine babesiosis; in addition, Babesia ovata and B. major are a group of benign bovine piroplasms. Therefore, species identification is important for diagnosis, epidemiological investigations and follow-up management. METHODS: Real-time PCR combined with high resolution melting (RT-PCR-HRM) analysis was used to detect and discriminate four Babesia species infective to cattle, including Babesia bovis, B. bigemina, B. major and B. ovata. The melting profiles and melting temperatures (Tm) of the amplicon targeting 18S rRNA revealed differences that can discriminate the four Babesia spp. Sensitivity and specificity of the analytical method were evaluated using 50 blood samples collected from experimentally infected cattle and 240 blood samples from areas where bovine babesiosis is an issue. RESULTS: RT-PCR-HRM analysis allowed to detect and discriminate four Babesia spp. (B. bovis, B. bigemina, B. major and B. ovata), which were responsible for bovine babesiosis in China. The protocol was validated with DNA samples from experimentally infected cattle and field infection in cattle. CONCLUSIONS: Our results indicate that RT-PCR-HRM is a fast and robust tool for the simultaneous detection and discrimination of four Babesia species that are responsible for bovine babesiosis in China. This approach is applicable for both field and experimental samples, thus it could be useful in epidemiological investigations and diagnoses of bovine babesiosis.

19.
Acta Biomater ; 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31669696

RESUMO

Recapitulating aligned cellular architectures of native tissues in vitro is important to engineer artificial tissue analogs with desired biological functions. Here a novel strategy is presented to direct three-dimensional (3D) cellular alignment by embedding cell/collagen hydrogel into the predefined electrohydrodynamically-printed microlattices. The cell/collagen hydrogel, originally filled within the printed microlattices uniformly, was found to gradually develop into densely-populated and highly-aligned bands along the longitudinal direction of the printed microlattices. The cellular alignment was highly dependent on the height, spacing and orientation of the microlattices. The presented method was applicable to multiple cell types including primary cardiomyocytes and the gaps formed between the aligned bands and the lateral walls of the microlattice facilitated the subsequent seeding and rapid alignment of other cell types which enables to engineer anisotropic multicellular tissue constructs. The engineered cardiac patches expressed mature cardiomyocyte-specific phenotypes and exhibited synchronous contractive activities. Multilayer cellular alignment with varied orientation in 3D collagen hydrogel was successfully achieved by using electrohydrodynamically-printed microlattices with layer-specific orientations. This exploration offers a promising way to engineer complex 3D tissue constructs with predefined cellular alignments. STATEMENT OF SIGNIFICANCE: Fabrication of biomimetic highly-aligned complex cellular architectures has a great significance to recapitulate the unique mechanical and physiological functions of the engineered tissues (e.g., heart tissue, neuron, muscle). Here, we introduced a novel strategy to direct 3D cellular alignment by embedding cell/collagen hydrogel into the predefined electrohydrodynamically-printed microlattices without any external stimuli. The microscopical study of the dynamic alignment process of cells and collagen fibers contributed to exploring the mechanism of autonomous formation of highly-aligned cellular bands. Multilayer cellular alignment with varied orientation in 3D collagen hydrogel was successfully achieved by using the microlattices with layer-specific orientations, which showed a promising way to engineer complex 3D tissue constructs with predefined cellular alignments.

20.
Fitoterapia ; 139: 104401, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31669964

RESUMO

Three previously undescribed (±)-3,4-dihydro-4-naphthyl-naphthalen-1(2H)-one derivatives were isolated from Juglans regia flowers. Elucidation of the 2D structures of these first-reported compounds was completed via regular spectroscopic methods. The assignment of racemic nature of these compounds was achieved using the examination of their chiral HPLC profiles. (±)-2,3-Dihydro-4',8,8'-trihydroxy-(1,1'-binaphthalen)-4(1H)-one, (±)-2,3-dihydro-4',5,8,8'-tetrahydroxy-(1,1'-binaphthalen)-4(1H)-one, and (±)-2,3-dihydro-1',5,5',8-tetrahydroxy-(1,2'-binaphthalen)-4(1H)-one were the structures of these racemic compounds, all taking on central chirality. The resolution of all the racemic compounds was conducted and achieved using a chiral HPLC procedure. The absolute configurations of the three isolated pairs of enantiomers were assigned via time-dependent density functional theory calculations from the electronic circular dichroism data. The findings in this paper demonstrated that the relevant biochemical reactions for the construction of these 3,4-dihydro-4-naphthyl-naphthalen-1(2H)-one derivatives in the test plant are nonselective. The (±)-2,3-dihydro-4',8,8'-trihydroxy-(1,1'-binaphthalen)-4(1H)-one showed selective inhibitory activity on tumor cells growth, preliminarily supporting the application of Juglans regia flowers to protect against cancers in a few Chinese folk areas.

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