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1.
Dalton Trans ; 50(7): 2616-2626, 2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33522543

RESUMO

Currently, the catalytic transformation and utilization of biomass-derived compounds are of great importance to the alleviation of environmental problems and sustainable development. Among them, furfural alcohol derived from biomass resources has been found to be one of the most prospective biomass platforms for high-value chemicals and biofuels. Herein, high-surface-area ZrO2 with abundant oxygen defects and surface acid-base sites was synthesized and used as a heterogeneous catalyst for the catalytic transfer hydrogenation of furfural into furfural alcohol using alcohol as a hydrogen donor. The as-synthesized ZrO2 exhibited excellent catalytic performance with 98.2% FA conversion and 97.1% FOL selectivity, even comparable with that of a homogeneous Lewis acid catalyst. A series of characterization studies and experimental results revealed that acid sites on the surface of ZrO2 could adsorb and activate the C[double bond, length as m-dash]O bond in furfural and base sites could facilitate the formation of alkoxide species. The synergistic effect of surface acid-base sites affords a harmonious environment for the reaction, which is crucial for catalytic transfer hydrogenation of furfural with high efficiency. Furthermore, the as-prepared ZrO2 catalyst also exhibited a potential application for the efficient catalytic transfer hydrogenation of a series of biomass-derived carbonyl compounds.

2.
J Diabetes Investig ; 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33449448

RESUMO

AIMS/INTRODUCTION: ß-Cell dysfunction is a hallmark of type 2 diabetes. In a previous pilot study, we identified an association between genetic variants within the human DACH1 gene and young-onset type 2 diabetes. Here, we characterized the function of dachb, the only dach homologue to be expressed in the pancreas, in developing zebrafish embryos. MATERIALS AND METHODS: We injected one-cell stage embryos with a dachb-morpholino (MO) or with the dachb-MO and dachb messenger ribonucleic acid, and determined the effect on the development of the pancreatic islet. We also carried out quantitative polymerase chain reaction and ribonucleic acid sequencing on the dachb-MO group to determine the effect of dachb knockdown on gene expression. RESULTS: MO-mediated dachb knockdown resulted in impaired islet cell development, with a significant decrease in both the ß-cell and islet cell numbers. This islet developmental defect was rescued when embryos were co-injected with dachb-MO and dachb messenger ribonucleic acid. Knockdown of dachb was associated with a significant downregulation of the ß-cell specific marker gene, insa, and the somatostatin cell marker, sst2, as well as regulators of pancreas development, ptf1a, neuroD, pax6a and nkx6.1, and the cell cycle gene, insm1a. Furthermore, ribonucleic sequencing analysis showed an upregulation of genes enriched in the forkhead box O and mitogen-activated protein kinase signaling pathways in the dachb-MO group, when compared with the control groups. CONCLUSIONS: Together, our results suggest the possible role of dachb in islet development in zebrafish.

3.
Gut ; 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431576

RESUMO

OBJECTIVE: Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) pathophysiology remains unclear. This study aims to characterise the molecular basis of HBV-ACLF using transcriptomics. METHODS: Four hundred subjects with HBV-ACLF, acute-on-chronic hepatic dysfunction (ACHD), liver cirrhosis (LC) or chronic hepatitis B (CHB) and normal controls (NC) from a prospective multicentre cohort were studied, and 65 subjects (ACLF, 20; ACHD, 10; LC, 10; CHB, 10; NC, 15) among them underwent mRNA sequencing using peripheral blood mononuclear cells (PBMCs). RESULTS: The functional synergy analysis focusing on seven bioprocesses related to the PBMC response and the top 500 differentially expressed genes (DEGs) showed that viral processes were associated with all disease stages. Immune dysregulation, as the most prominent change and disorder triggered by HBV exacerbation, drove CHB or LC to ACHD and ACLF. Metabolic disruption was significant in ACHD and severe in ACLF. The analysis of 62 overlapping DEGs further linked the HBV-based immune-metabolism disorder to ACLF progression. The signatures of interferon-related, neutrophil-related and monocyte-related pathways related to the innate immune response were significantly upregulated. Signatures linked to the adaptive immune response were downregulated. Disruptions of lipid and fatty acid metabolism were observed during ACLF development. External validation of four DEGs underlying the aforementioned molecular mechanism in patients and experimental rats confirmed their specificity and potential as biomarkers for HBV-ACLF pathogenesis. CONCLUSIONS: This study highlights immune-metabolism disorder triggered by HBV exacerbation as a potential mechanism of HBV-ACLF and may indicate a novel diagnostic and treatment target to reduce HBV-ACLF-related mortality.

4.
Environ Int ; 149: 106406, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33508533

RESUMO

Cadmium is known as an environmental pollutant that contributes to pancreatic damage and the pathogenesis of diabetes. However, less attention has been devoted to elucidating the mechanisms underlying Cd-induced pancreatic ß-cell dysfunction and the role of Cd toxicity in the development of diabetes. In this study, we demonstrated that exposure to Cd caused remarkable pancreatic ß-cell dysfunction and death, both in vitro and in vivo. Lipidomic analysis of Cd-exposed pancreatic ß-cells using high-resolution mass spectrometry revealed that Cd exposure altered the profile and abundance of lipids. Cd exposure induced intracellular lipid accumulation, promoted lipid biogenesis, elevated pro-inflammatory lipid contents and inhibited lipid degradation. Furthermore, Cd exposure upregulated the expression levels of TNF-α, IL-1ß and IL-6 in pancreatic ß-cells and elevated the TNF-α, IL1-ß and IL-6 levels in the serum and pancreas. Taken together, the results of our study demonstrated that environmental relevant Cd exposure causes pro-inflammatory lipids elevation and insulin secretion dysfunction in ß-cells and hence exaggerates diabetes development. Combined exposure to environmental hazardous chemicals might markedly increase the probability of developing diabetes in humans. This study provides new metabolic and pharmacological targets for antagonizing Cd toxicity.

5.
Metabolism ; 114: 154402, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33053398

RESUMO

OBJECTIVE: Nicotinamide adenine dinucleotide (NAD) is an essential molecule participating in multiple physiological and pathophysiological processes. In diabetic cornea, the NAD+-consuming enzyme SIRT1 was down-regulated and contributed to the delayed wound healing. However, the impact of hyperglycemia on corneal NAD+ biosynthesis remained elusive. This study was to investigate the relationship of NAD+ biosynthesis and the delayed corneal wound healing in diabetic mice. METHODS: Type 1 diabetes mellitus (DM) mice were induced by streptozotocin and corneal epithelial wound healing models were constructed by epithelial scraping. The NAD+ contents of corneal epithelium were measured using the NAD/NADH quantification kit. Expression of key enzymes involved in the NAD+ biosynthesis in type 1 DM mice and type 2 DM patients were analyzed. The nicotinamide phosphoribosyltransferase (NAMPT)-specific siRNA and the selective inhibitor FK866 were used to achieve the blockade of NAMPT, whereas exogenous NAD+ and its precursors were replenished to the corneal epithelial cells and DM mice. RESULTS: Hyperglycemia attenuated NAD+ content and NAMPT expression in the corneal epithelium of both type 1 DM mice and type 2 DM patients. Local knockdown of NAMPT by siRNA or FK866 consistently recapitulated the delayed corneal epithelial wound healing in normal mice. Moreover, NAD+ replenishment recovered the impaired proliferation and migration capacity by either FK866 or high glucose treatment in cultured corneal epithelial cells. Furthermore, in DM mice, NAD+ and its precursors nicotinamide mononucleotide and nicotinamide riboside also facilitated corneal epithelial and nerve regeneration, accompanied with the recovered expression of SIRT1 and phosphorylated EGFR, AKT, and ERK1/2 in epithelium and corneal sensitivity. CONCLUSION: Hyperglycemia-reduced NAD+ biosynthesis and contributed to the impaired epithelial wound healing in DM mice. The replenishment of NAD+ and its precursors facilitated diabetic corneal wound healing and nerve regeneration, which may provide a novel therapeutic strategy for the treatment of diabetic corneal complications.


Assuntos
Lesões da Córnea/metabolismo , Diabetes Mellitus Experimental/metabolismo , Epitélio Anterior/lesões , Hiperglicemia/metabolismo , NAD/biossíntese , Cicatrização/fisiologia , Animais , Córnea/metabolismo , Epitélio Anterior/metabolismo , Camundongos
6.
J Hazard Mater ; 402: 123926, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33254826

RESUMO

Bisphenol A (BPA), an environmental endocrine-disrupting compound, has been revealed associated with metabolic disorders such as obesity, prediabetes, and type 2 diabetes (T2D). However, its underlying mechanisms are still not fully understood. Here, we provide new evidence that BPA is a risk factor for T2D from a case-control study. To explore the detailed mechanisms, we used two types of diet models, standard diet (SD) and high-fat diet (HFD), to study the effects of long-term BPA exposure on prediabetes in 4-week-old mice. We found that BPA exposure for 12 weeks exacerbated HFD-induced prediabetic symptoms. Female mice showed increased body mass, serum insulin level, and impaired glucose tolerance, while male mice only exhibited impaired glucose tolerance. No change was found in SD-fed mice. Besides, BPA exposure enhanced astrocyte-dependent hypothalamic inflammation in both male and female mice, which impaired proopiomelanocortin (POMC) neuron functions. Moreover, eliminating inflammation by toll-like receptor 4 (TLR4) knockout significantly abolished the effects of BPA on the hypothalamus and diet-induced prediabetes. Taken together, our data establish a key role for TLR4-dependent hypothalamic inflammation in regulating the effects of BPA on prediabetes.

7.
Chemosphere ; : 129017, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33261842

RESUMO

This work describes a novel application of atmospheric pressure gas chromatography time-of-flight mass spectrometry (APGC-TOF-MS) combined with solid-phase microextraction (SPME) for the simultaneous analysis of hydrocarbons and naphthenic acids (NAs) species in raw and ozone-treated oil sands process water (OSPW). SPME method using polydimethylsiloxane (PDMS)-coated fibers was validated using gas chromatography with flame ionization detector (GC-FID) to ensure the SPME extractions were operated appropriately. The ionization pathways of the hydrocarbon species in OSPW in the APGC source were verified by analyzing a mixture of eight polyaromatic hydrocarbons which were ionized primarily via charge transfer to produce [M+] while NAs in OSPW were found to be ionized through protonation to generate [MH+] in the wet APGC source. SPME/APGC-TOF-MS analysis demonstrated a different composition profile in OSPW #1, with 74.5% of hydrocarbon species, 23.4% of O2-NAs, and 2.1% of the oxidized NA species at extraction pH 2.0 compared with that obtained by UPLC-TOF-MS analysis (36.9% of O2-NAs, 26.8% of O3-NAs, 24.9% of O4-NAs, 9.1% of O5-NAs, 2.3% of O6-NAs). Moreover, the peak areas of the total NAs and the total peak areas of NAs + hydrocarbons measured by SPME/APGC-TOF-MS correlated excellently with the total NA concentration determined by UPLC-TOF-MS (R2 = 0.90) and the concentrations of the total acid-extractable organics determined by SPME/GC-FID (R2 = 0.98), respectively. APGC-TOF-MS integrated with the SPME techniques could extend the range of target compounds and be a promising alternative to evaluate and characterize NAs and hydrocarbon in different water types.

8.
Sci Rep ; 10(1): 21510, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33299036

RESUMO

We previously documented that the CaV3.3 isoform of T-type calcium channels (T-channels) is inhibited by clinically relevant concentrations of volatile anaesthetics, including isoflurane. However, little is understood about the functional role of CaV3.3 channels in anaesthetic-induced hypnosis and underlying neuronal oscillations. To address this issue, we used CaV3.3 knock-out (KO) mice and a panselective T-channel blocker 3,5-dichloro-N-[1-(2,2-dimethyltetrahydro-pyran-4-ylmethyl)-4-fluoro-piperidin-4-ylmethyl]-benzamide (TTA-P2). We found that mutant mice injected with the vehicle showed faster induction of hypnosis than wild-type (WT) mice, while the percent isoflurane at which hypnosis and immobility occurred was not different between two genotypes. Furthermore, we found that TTA-P2 facilitated isoflurane induction of hypnosis in the CaV3.3 KO mice more robustly than in the WT mice. Isoflurane-induced hypnosis following injections of TTA-P2 was accompanied with more prominent delta and theta EEG oscillations in the mutant mice, and reached burst-suppression pattern earlier when compared to the WT mice. Our findings point to a relatively specific value of CaV3.3 channels in anaesthetic induced hypnosis. Furthermore, we propose that T-channel blockers may be further explored as a valuable adjunct to reducing the usage of potent volatile anaesthetics, thereby improving their safety.

9.
Appl Opt ; 59(36): 11240-11245, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33362045

RESUMO

Niobium carbide (Nb2C), a novel two-dimensional MXene material, has attracted much attention due to its outstanding electronic and optical properties. In this work, a microfiber-based few-layer Nb2C saturable absorber (SA) is fabricated by the magnetron sputtering deposition technique. The reverse saturable absorption (RSA) response of few-layer Nb2C nanosheets is observed with I-scan measurements. The square-wave pulses (SWPs) are generated by using the as-prepared microfiber-based few-layer Nb2C SA in an erbium-doped fiber laser. The SWP width increases from 0.33 to 2.061 ns with the single pulse energy increases linearly up to 0.89 nJ while the amplitude remains as a constant. In addition, nonlinear polarization rotation mode-locking fiber lasers with different cavity lengths are constructed to explore the formation conditions of SWP. Our results indicate that the RSA effect of the few-layer Nb2C nanosheets plays a decisive role in the formation of the SWP.

10.
Expert Rev Gastroenterol Hepatol ; : 1-11, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33174441

RESUMO

Introduction: Liver metastasis is the main cause of death in colorectal cancer (CRC). Pre-metastatic niche (PMN), a favorable microenvironment for cancer cells colonization at the distant organ, plays a pivotal role in CRC liver metastasis (CRCLM). Our understanding of the mechanisms mediating the formation of liver PMN in CRC has been significantly advanced in recent years, there are still many challenges and questions that remain. Areas covered: This review covers cellular and molecular components, and the interaction of the primary cancer with the resident microenvironment of the distant organ that leads to PMN formation in CRCLM based on the latest literature. Expert Opinion: Various cellular and molecular events are involved in the liver PMN formation in CRC such as bone marrow-derived cells (BMDCs), hepatic stellate cells, Kupffer cells, extracellular matrix, and CRC-derived factors. The formation of the liver PMN depends on a complex interaction of CRC with the liver microenvironment including BMDCs recruitment, vascularization, immunosuppression, inflammatory response, and extracellular matrix remodeling. This review firstly discusses on the cellular and molecular components contributing to the formation of the liver PMN in CRC, so as to provide new ideas for designing effective therapeutic strategies and prognostic markers for CRCLM.

11.
Medicine (Baltimore) ; 99(38): e22004, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32957318

RESUMO

BACKGROUND: Mannitol and hypertonic saline (HTS) are effective in reducing intracranial pressure (ICP) after severe traumatic brain injury (TBI). However, their efficacy on the ICP has not been evaluated rigorously. OBJECTIVE: To evaluate the efficacy of repeated bolus dosing of HTS and mannitol in similar osmotic burdens to treat intracranial hypertension (ICH) in patients with severe TBI. METHODS: The authors used an alternating treatment protocol to evaluate the efficacy of HTS with that of mannitol given for ICH episodes in patients treated for severe TBI at their hospital during 2017 to 2019. Doses of similar osmotic burdens (20% mannitol, 2 ml/kg, or 10% HTS, 0.63 ml/kg, administered as a bolus via a central venous catheter, infused over 15 minutes) were given alternately to the individual patient with severe TBI during ICH episodes. The choice of osmotic agents for the treatment of the initial ICH episode was determined on a randomized basis; osmotic agents were alternated for every subsequent ICH episode in each individual patient. intracranial pressure (ICP), mean arterial pressure (MAP), and cerebral perfusion pressure (CPP) were continuously monitored between the beginning of each osmotherapy and the return of ICP to 20 mm Hg. The duration of the effect of ICP reduction (between the beginning of osmotherapy and the return of ICP to 20 mm Hg), the maximum reduction of ICP and its time was recorded after each dose. Serum sodium and plasma osmolality were measured before, 0.5 hours and 3 hours after each dose. Adverse effects such as central pontine myelinolysis (CPM), severe fluctuations of serum sodium and plasma osmolality were assessed to evaluate the safety of repeated dosing of HTS and mannitol. RESULTS: Eighty three patients with severe TBI were assessed, including 437 ICH episodes, receiving 236 doses of HTS and 221 doses of mannitol totally. There was no significant difference between equimolar HTS and mannitol boluses on the magnitude of ICP reduction, the duration of effect, and the time to lowest ICP achieved (P > .05). The proportion of efficacious boluses was higher for HTS than for mannitol (P = .016), as was the increase in serum sodium (P = .038). The serum osmolality increased immediately after osmotherapy with a significant difference (P = .017). No cases of CPM were detected. CONCLUSION: Repeat bolus dosing of 10% HTS and 20% mannitol appears to be significantly and similarly effective for treating ICH in patients with severe TBI. The proportion of efficacious doses of HTS on ICP reduction may be higher than mannitol.


Assuntos
Lesões Encefálicas Traumáticas/complicações , Diuréticos Osmóticos/uso terapêutico , Hipertensão Intracraniana/tratamento farmacológico , Hipertensão Intracraniana/etiologia , Manitol/uso terapêutico , Solução Salina Hipertônica/uso terapêutico , Adulto , Circulação Cerebrovascular/efeitos dos fármacos , Diuréticos Osmóticos/administração & dosagem , Diuréticos Osmóticos/efeitos adversos , Feminino , Humanos , Pressão Intracraniana/efeitos dos fármacos , Masculino , Manitol/administração & dosagem , Manitol/efeitos adversos , Pessoa de Meia-Idade , Solução Salina Hipertônica/administração & dosagem , Solução Salina Hipertônica/efeitos adversos , Índices de Gravidade do Trauma
12.
Biomed Pharmacother ; 131: 110747, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32932047

RESUMO

2'-Acetylacteoside-(2'-AA), a bioactive constituent isolated from Cistanche deserticola, has been proven to possess a variety of important pharmacological effects, thus brought an increased amount of scientists' attention. As the extract of C. deserticola exhibited significant anti-osteoporotic bioactivity in our previous study, we proposed that 2'-AA maybe one of the responsibilities. As a result, 2'-AA (10, 20 and 40 mg/kg body weight/day) exhibited significant anti-osteoporotic effects on ovariectomized (OVX) mice after 12 weeks of oral administration, confirmed by the increased bone mineral density, enhanced bone strength and improved trabecular bone micro-architecture including bone mineral content, tissue mineral content, trabecular number, and trabecular separation of OVX mice. Moreover, the properties of bone resorption markers including cathepsin K, TRAP and deoxypyridinoline were significantly suppressed, whereas the activities of bone formation index like ALP and BGP as well as the weights of the body, uterus, and vagina were seemingly not influenced by 2'-AA intervention. Mechanistically, the above therapeutic effect of 2'-AA on bone resorption of OVX mice operated maybe mainly through RANKL/RANK/TRAF6-mediated NF-κB/NFATc1 pathway, which was confirmed by the down-regulated expressions of RANK, TRAF6, IκB kinase ß, NF-κB and NFATc1. Summarily, 2'-AA exhibited significant anti-osteoporotic activity and may be regarded as a promising anti-osteoporotic candidate for future clinical trial.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32908556

RESUMO

Objective: The study aimed to explore the effect of total flavonoids of Oxytropis falcata Bunge (FOFB) on the expression of p-JAK1/p-STAT1 and SOCS3 proteins in idiopathic pulmonary fibrosis (IPF). Methods: Rats model with IPF was established by one-off intratracheal injection of bleomycin (BLM, 5 mg/kg). After 14 days, the same volume of low dose (100 mg/kg), medium dose (200 mg/kg), and high dose (400 mg/kg) of FOFB and prednisolone acetate (20 mg/kg) as positive control drugs, as well as normal saline, were orally administered to rats once a day for 28 consecutive days. Subsequently, the degree of fibrosis and alveolitis in rat lung tissue was observed, respectively, by HE and Masson staining. Further more, observing the ultrastructure of lung tissue by transmission electron microscopy (TEM), the detection of JAK/STAT pathway related indicators including p-JAK1, p-STAT1, and SOCS3 with immunohistochemistry and SOCS3 with real-time PCR (RT-PCR) was performed. Results: Compared with the BLM group, the degree of alveolitis and fibrosis improved significantly, and the expression of p-JAK1 and p-STAT1 decreased; conversely, the expression of SOCS3 increased in the treatment group. Conclusion: IPF causes high expression of p-JAK1 and p-STAT1 and low expression of SOCS3. FOFB can play a role in the treatment of IPF via upregulating SOCS3 and downregulating p-JAK1 and p-STAT1.

14.
Anal Chem ; 92(19): 13319-13326, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32897047

RESUMO

Capture, analysis, and inactivation of circulating tumor cells (CTCs) have emerged as important issues for the early diagnosis and therapy of cancer. In this study, an all-in-one sensing device was developed by integrating magnetic metal-organic framework (magMOF) nanoparticles (NPs) and TiO2 nanotube arrays (TiNTs). The magMOF NPs are composed of a magnetic Fe3O4 core and a MIL-100(Fe) shell, which is loaded with glucose oxidase (GOD) and provides an intensive starvation therapy by catalyzing the consumption of cellular nutrients, thus accelerating the generation of intracellular iron ions by MIL-100(Fe) dissolution. Importantly, these iron ions not only lead to an intensive Fenton-like reaction but also establish an excellent correlation of electrochemical intensities with cancer cell numbers. Owing to the intracellular magMOF NPs, the CTCs were magnetically collected onto TiNTs. The exogenous ·OH radicals generated by TiNT photocatalysis trigger iron ions to be rapidly released out and subsequently detected via differential pulse voltammetry using TiNTs as the electrode. An excellent correlation of differential pulse voltammetry intensities with CTC numbers is obtained from 2 to 5000 cell mL-1. This nanoplatform not only paves a way to combine starvation therapy agents with Fenton-like reaction for chemodynamic therapy but also opens up new insights into the construction of all-in-one chips for CTC capture and diagnosis.

15.
Ocul Surf ; 18(4): 748-760, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32841745

RESUMO

PURPOSE: Hydrogels derived from decellularized tissues provide superior biocompatibility, tenability and tissue-specific extracellular matrix (ECM) components. Based on the preparation of decellularized porcine cornea (DPC), here we developed an injectable and transparent hydrogel for the regeneration of epithelium and stroma in focal corneal defects. METHODS: The DPC-derived hydrogel was prepared with N-cyclohexyl-N'-(2-morpholinethyl) carbodiimide metho-p-toluenesulfonate/N-hydroxysuccinimide (CMC/NHS) as cross-linkers. The characteristics of the hydrogel were analyzed and its cytocompatibility was assessed by Live/Dead and Cell Counting Kit (CCK)-8 assays. Immunofluorescence staining, quantitative PCR and Western blot analyses were performed to assess the relative protein and gene expression in corneal fibroblasts on hydrogel. The safety and efficiency of the hydrogel for repairing focal corneal defects in rabbit were measured by slit-lamp, anterior segment optical coherence tomography (AS-OCT), confocal microscopy and histological analyses. RESULTS: The DPC-derived hydrogel cross-linked with CMC/NHS assumed favorable transparency, exhibited distinct mechanical properties and preserved the ECM components of native porcine cornea (NPC). In vitro experiments showed that the hydrogel maintained the phenotype, supported the proliferation and promoted the ECM synthesis of corneal fibroblasts. When injected onto rabbit corneas, the hydrogel rapidly covered, solidified and formed a smooth surface on the focal defect. Corneal epithelium was fully regenerated within 3 days. The thickness of the corneal epithelium and stroma was restored at 12 weeks after surgery without significant inflammation or scar formation. Notably, the hydrogel showed no harmful effects on the resident stroma and endothelium. CONCLUSIONS: The DPC-derived hydrogel may represent a promising biomaterial for corneal epithelial and stromal regeneration.

16.
Am J Pathol ; 190(11): 2237-2250, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32858016

RESUMO

The insulin and Wnt signaling pathways are involved in cell proliferation, tissue homeostasis, and tumorigenesis. However, their interrelationship in the pathophysiological process of diabetic corneal injury remains unclear. In this study, the role of insulin in the diabetic cornea was investigated in vitro, using cultured TKE2 cells and trigeminal ganglion neurons, and in vivo, by assessing corneal wound-healing responses in diabetic mice. A selective Wnt antagonist (XAV-939) and activator (BML-284) were used to regulate the interactions between insulin and the Wnt pathway. The results demonstrated that insulin promoted corneal epithelial wound healing and sensation recovery, whereas the expression of molecules involved in the Wnt/ß-catenin pathway was also up-regulated in the injured corneal epithelium. However, XAV-939 limited the insulin-induced epithelial and corneal nerve repair. By contrast, BML-284 treatment promoted the healing of the corneal epithelium and corneal nerve repair in diabetic mice. These results indicate that insulin, via Wnt signaling, contributes to diabetic corneal epithelial wound healing and nerve injury recovery and is, therefore, a potential protective factor for diabetic corneal epithelial wounds and nerve injury.


Assuntos
Lesões da Córnea , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Insulina/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Córnea/metabolismo , Córnea/patologia , Lesões da Córnea/tratamento farmacológico , Lesões da Córnea/metabolismo , Lesões da Córnea/patologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Masculino , Camundongos
17.
Chem Commun (Camb) ; 56(71): 10333-10336, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32760961

RESUMO

A smooth TiO2 nanotube-based membrane (S-TiNM) is demonstrated to be effective in reducing the Raman-scattering loss in 3D porous structures. Using the photocatalytic reduction of 4-nitrothiophenol as a model, the S-TiNMs show promising potential as sensitive SERS substrates to investigate photocatalytic reactions on site.

18.
Oncol Lett ; 20(2): 1931-1937, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32724437

RESUMO

Lung cancer is one of the most common cancers that threaten human life and health. Recently, microRNAs (miRNAs) have been shown to play a unique role in many malignancies. Although the dysregulation of miR-147 has been detected in non-small cell lung cancer (NSCLC), the biological function of miR-147 is still unknown in NSCLC. The expression of miR-147 was observed by real-time quantitative polymerase chain reaction (RT-qPCR). Methyl thiazolyl tetrazolium (MTT) and Transwell assays were used to investigate the function of miR-147 in NSCLC. Target genes of miR-147 were verified using dual luciferase reporter assay. Western blot analysis was used to explore the PI3K/AKT pathway. The expression of miR-147 was decreased in NSCLC tissues, which was associated with poor prognosis in NSCLC patients. Furthermore, overexpression of miR-147 inhibited the viability and metastasis of NSCLC cells. In addition, miR-147 inhibited epithelial-mesenchymal transition (EMT) and inactivated the PI3K/AKT pathway in NSCLC. Furthermore, miR-147 directly targets brain-derived neurotrophic factor (BDNF) and negatively regulates BDNF expression in NSCLC. Upregulation of BDNF attenuated the inhibitory effect of miR-147 in NSCLC. In conclusion, miR-147 inhibits cell proliferation, migration and invasion in NSCLC through suppressing BDNF expression.

19.
Genome Biol Evol ; 12(11): 2002-2014, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-32687170

RESUMO

Rhizobia are soil bacteria capable of forming symbiotic nitrogen-fixing nodules associated with leguminous plants. In fast-growing legume-nodulating rhizobia, such as the species in the family Rhizobiaceae, the symbiotic plasmid is the main genetic basis for nitrogen-fixing symbiosis, and is susceptible to horizontal gene transfer. To further understand the symbioses evolution in Rhizobiaceae, we analyzed the pan-genome of this family based on 92 genomes of type/reference strains and reconstructed its phylogeny using a phylogenomics approach. Intriguingly, although the genetic expansion that occurred in chromosomal regions was the main reason for the high proportion of low-frequency flexible gene families in the pan-genome, gene gain events associated with accessory plasmids introduced more genes into the genomes of nitrogen-fixing species. For symbiotic plasmids, although horizontal gene transfer frequently occurred, transfer may be impeded by, such as, the host's physical isolation and soil conditions, even among phylogenetically close species. During coevolution with leguminous hosts, the plasmid system, including accessory and symbiotic plasmids, may have evolved over a time span, and provided rhizobial species with the ability to adapt to various environmental conditions and helped them achieve nitrogen fixation. These findings provide new insights into the phylogeny of Rhizobiaceae and advance our understanding of the evolution of symbiotic nitrogen fixation.

20.
Int J Syst Evol Microbiol ; 70(6): 3930-3931, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32496182

RESUMO

According to Rule 37a of the International Code of Nomenclature of Prokaryotes, the name of a taxon must be changed if the nomenclatural type of the taxon is excluded. Recently, in a transfer of actinobacterial species, three species - Friedmanniella endophytica Tuo et al. 2016, Lysinimicrobium sediminis Hamada et al. 2017 and Lechevalieria rhizosphaerae Zhao et al. 2017 - were not transferred with their type species. Therefore, to resolve these nomenclatural issues, Microlunatus kandeliicorticis nom. nov., Demequina sediminis comb. nov. and Lentzea rhizosphaerae comb. nov. are proposed, respectively.


Assuntos
Actinobacteria/classificação , Filogenia , Propionibacteriaceae/classificação
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