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1.
Nat Commun ; 15(1): 2098, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459034

RESUMO

Yutu-2 rover conducted an exciting expedition on the 41st lunar day to investigate a fin-shaped rock at Longji site (45.44°S, 177.56°E) by extending its locomotion margin on perilous peaks. The varied locomotion encountered, especially multi-form wheel slippage, during the journey to the target rock, established unique conditions for a fin-grained lunar regolith analysis regarding bearing, shear and lateral properties based on terramechanics. Here, we show a tri-aspect characterization of lunar regolith and infer the rock's origin using a digital twin. We estimate internal friction angle within 21.5°-42.0° and associated cohesion of 520-3154 Pa in the Chang'E-4 operational site. These findings suggest shear characteristics similar to Apollo 12 mission samples but notably higher cohesion compared to regolith investigated on most nearside lunar missions. We estimate external friction angle in lateral properties to be within 8.3°-16.5°, which fills the gaps of the lateral property estimation of the lunar farside regolith and serves as a foundational parameter for subsequent engineering verifications. Our in-situ spectral investigations of the target rock unveil its composition of iron/magnesium-rich low-calcium pyroxene, linking it to the Zhinyu crater (45.34°S, 176.15°E) ejecta. Our results indicate that the combination of in-situ measurements with robotics technology in planetary exploration reveal the possibility of additional source regions contributing to the local materials at the Chang'E-4 site, implying a more complicated geological history in the vicinity.

2.
Sci Rep ; 14(1): 4310, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383608

RESUMO

Addressing the challenge of efficiently solving multi-objective optimization problems (MOP) and attaining satisfactory optimal solutions has always posed a formidable task. In this paper, based on the chicken swarm optimization algorithm, proposes the non-dominated sorting chicken swarm optimization (NSCSO) algorithm. The proposed approach involves assigning ranks to individuals in the chicken swarm through fast non-dominance sorting and utilizing the crowding distance strategy to sort particles within the same rank. The MOP is tackled based on these two strategies, with the integration of an elite opposition-based learning strategy to facilitate the exploration of optimal solution directions by individual roosters. NSCSO and 6 other excellent algorithms were tested in 15 different benchmark functions for experiments. By comprehensive comparison of the test function results and Friedman test results, the results obtained by using the NSCSO algorithm to solve the MOP problem have better performance. Compares the NSCSO algorithm with other multi-objective optimization algorithms in six different engineering design problems. The results show that NSCSO not only performs well in multi-objective function tests, but also obtains realistic solutions in multi-objective engineering example problems.

3.
J Environ Manage ; 342: 118281, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37290309

RESUMO

The production of lactic acid (LA) from agricultural wastes attracts great attention because of the sustainability and abundance of lignocellulosic feedstocks, as well as the increasing demand for biodegradable polylactic acid. In this study, we isolated a thermophilic strain Geobacillus stearothermophilus 2H-3 for use in robust production of L-(+)LA under the optimal conditions of 60 °C, pH 6.5, which were consistent with the whole-cell-based consolidated bio-saccharification (CBS) process. Sugar-rich CBS hydrolysates derived from various agricultural wastes, including corn stover, corncob residue, and wheat straw, were used as the carbon sources for 2H-3 fermentation by directly inoculating 2H-3 cells into the CBS system, without intermediate sterilization, nutrient supplementation, or adjustment of fermentation conditions. Thus, we successfully combined two whole-cell-based steps into a one-pot successive fermentation process to efficiently produce LA with high optical purity (99.5%), titer (51.36 g/L), and yield (0.74 g/gbiomass). This study provides a promising strategy for LA production from lignocellulose through CBS and 2H-3 fermentation integration.


Assuntos
Ácido Láctico , Lignina , Lignina/química , Fermentação , Biomassa
4.
J Anim Sci Biotechnol ; 13(1): 75, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35781353

RESUMO

BACKGROUND: The pig is an economically important livestock species and is a widely applied large animal model in medical research. Enhancers are critical regulatory elements that have fundamental functions in evolution, development and disease. Genome-wide quantification of functional enhancers in the pig is needed. RESULTS: We performed self-transcribing active regulatory region sequencing (STARR-seq) in the porcine kidney epithelial PK15 and testicular ST cell lines, and reliably identified 2576 functional enhancers. Most of these enhancers were located in repetitive sequences and were enriched within silent and lowly expressed genes. Enhancers poorly overlapped with chromatin accessibility regions and were highly enriched in chromatin with the repressive histone modification H3K9me3, which is different from predicted pig enhancers detected using ChIP-seq for H3K27ac or/and H3K4me1 modified histones. This suggests that most pig enhancers identified with STARR-seq are endogenously repressed at the chromatin level and may function during cell type-specific development or at specific developmental stages. Additionally, the PPP3CA gene is associated with the loin muscle area trait and the QKI gene is associated with alkaline phosphatase activity that may be regulated by distal functional enhancers. CONCLUSIONS: In summary, we generated the first functional enhancer map in PK15 and ST cells for the pig genome and highlight its potential roles in pig breeding.

5.
Med Sci Monit ; 27: e931970, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34911926

RESUMO

BACKGROUND Forkhead box protein M1 (FoxM1) is an important transcription factor involved in the development and progression of various malignancies. However, its role in nasopharyngeal carcinoma (NPC) remains largely unknown. This study aimed to assess the effect of FoxM1 on NPC cell tumorigenesis as well as the underlying mechanism. MATERIAL AND METHODS NPC cell lines CNE-1 and CNE-2 were treated with vehicle and FoxM1 inhibitor thiostrepton or transfected with small interfering RNA. CCK-8 assay, flow cytometric assay, and Hoechst 33258 staining were performed to assess the viability, apoptosis and nuclear morphological impairment, and cell cycle, respectively. The expression of apoptosis-related caspase-3 and caspase-9 was detected by western blot analysis The tumor growth in the mouse xenograft model of NPC treated with thiostrepton or control was assessed. The expression of Wnt/ß-catenin signaling proteins p27, FoxM1, S phase kinase-associated protein 2 (SKP2), and Cyclin D1 were determined both in cells and xenograft tissues by western blot analysis. RESULTS Inhibition of FoxM1 by thiostrepton significantly suppressed NPC cell viability, induced apoptosis, increased cell cycle arrest, impaired nuclear morphology, and reduced NPC cell-derived tumor xenograft growth. Mechanistically, inhibition or knockdown of FoxM1 inactivated the Wnt/ß-catenin signaling pathway, as demonstrated by altered expression of Wnt/ß-catenin signaling-related genes, including p27, SKP2, and cyclin D1, in both NPC cells and xenograft tissues. CONCLUSIONS We identified FoxM1 as a novel regulator of NPC cell tumorigenesis in vitro and in vivo. Targeting FoxM1 could be a promising therapeutic strategy against NPC.


Assuntos
Carcinogênese/metabolismo , Proteína Forkhead Box M1/metabolismo , Carcinoma Nasofaríngeo/etiologia , Neoplasias Nasofaríngeas/etiologia , Via de Sinalização Wnt , Animais , Apoptose , Western Blotting , Linhagem Celular Tumoral , Proteína Forkhead Box M1/fisiologia , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Transplante de Neoplasias
6.
Nat Genet ; 53(7): 1075-1087, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099928

RESUMO

Animal interphase chromosomes are organized into topologically associating domains (TADs). How TADs are formed is not fully understood. Here, we combined high-throughput chromosome conformation capture and gene silencing to obtain insights into TAD dynamics in Xenopus tropicalis embryos. First, TAD establishment in X. tropicalis is similar to that in mice and flies and does not depend on zygotic genome transcriptional activation. This process is followed by further refinements in active and repressive chromatin compartments and the appearance of loops and stripes. Second, within TADs, higher self-interaction frequencies at one end of the boundary are associated with higher DNA occupancy of the architectural proteins CTCF and Rad21. Third, the chromatin remodeling factor ISWI is required for de novo TAD formation. Finally, TAD structures are variable in different tissues. Our work shows that X. tropicalis is a powerful model for chromosome architecture analysis and suggests that chromatin remodeling plays an essential role in de novo TAD establishment.


Assuntos
Genoma , Modelos Moleculares , Conformação de Ácido Nucleico , Xenopus/genética , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas de Ciclo Celular/genética , Cromatina/genética , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina , Biologia Computacional/métodos , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Genômica/métodos , Fenótipo , Xenopus/embriologia , Proteínas de Xenopus/genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-32635241

RESUMO

The disparity of rural and urban hospital utilization has aroused much concern. With the improvement of their living standards, patients in rural areas have an emerging need for traveling across borders for better medical treatment in China. This paper reveals the medical tourism of rural residents towards urban hospitals driven by hospital needs and points out that such disparities may be caused by medical tourism. The ratio of people aged 65 and above in total rural populations was used to identify the potential target customers for medical tourism. Based on rural and urban datasets ranging from 2007-2017 on the provincial level, this paper presents a mobile treatment model and market concentration model with an ecological foundation. The feasible generalized least squared approach was used in the estimation of the fixed-effect regressions. The study found that there was a positive and significant relationship between rural old-age ratios and urban inpatient visits from different income groups. On average, a one percent rise in rural old-age ratio would increase the inpatient visits of urban hospitals by 138 thousand persons. There was also a positive and significant relationship between the rural old-age ratio and the market concentration of urban inpatient visits. It was found that the rural old-age ratio significantly influenced the market concentration of urban inpatient visits in the middle-high income regions. The research showed that each income group from the rural aged population had participated in medical tourism, traveled to urbanized regions and made inpatient visits to urbanized medical facilities. It was also indicated that the rural aged population, especially from the middle-high income groups had a positive and significant influence on the market concentration of urban inpatient visits in the province.


Assuntos
Turismo Médico , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , População Rural , Idoso , Envelhecimento , China , Cidades , Disparidades em Assistência à Saúde , Humanos , População Urbana
8.
Carbohydr Polym ; 241: 116400, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32507165

RESUMO

Cost-efficient production of pullulan is of great importance but remains challenging due largely to the high-cost carbon sources. Lignocellulosic biomass is considered an alternative carbon source for industrial pullulan production, while new fungus producers that co-utilizing lignocellulose-derived glucose and xylose are required. In this study, a new fungus Aureobasidium melanogenum TN2-1-2 showed simultaneously assimilation of glucose and xylose and could produce pigment-free pullulan due to its deficiency in melanin synthesis. The ability of TN2-1-2 producing pullulan was remarkably robust in the presence of varying glucose to xylose ratios and ionic salt concentrations. Furthermore, condensed lignocellulosic hydrolysates obtained by consolidated biosaccharification was used as the pullulan production medium without supplying any nutrients, and pigment-free pullulan was produced by TN2-1-2 with the titer and yield of 55.1 g/L and 0.5 gPullulan/gCBS hydrolysate, respectively. Hence, this work provides a potential industrial pullulan producer TN2-1-2 and new insight into the lignocellulose bioconversion to pullulan.


Assuntos
Aureobasidium/metabolismo , Glucanos/biossíntese , Lignina/metabolismo , Fermentação , Glucose , Xilose
9.
Chem Commun (Camb) ; 56(46): 6285-6288, 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32379851

RESUMO

An Al centre-powered graphitic nanozyme derived from a metal organic framework was first developed for a chemodynamic tumor treatment. By virtue of the rapid and efficient generation of ˙OH in the slightly acidic tumor microenvironment, this nanozyme afforded high anti-tumor efficacy both in living cells and in vivo.


Assuntos
Alumínio/administração & dosagem , Grafite/administração & dosagem , Ferro/administração & dosagem , Neoplasias/tratamento farmacológico , Nitrilas/administração & dosagem , Alumínio/química , Animais , Catálise , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Grafite/química , Humanos , Peróxido de Hidrogênio/farmacologia , Concentração de Íons de Hidrogênio , Radical Hidroxila/metabolismo , Ferro/química , Azul de Metileno/química , Camundongos Nus , Neoplasias/patologia , Nitrilas/química , Microambiente Tumoral
10.
RSC Adv ; 10(29): 17129-17142, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35521439

RESUMO

The properties of lignocellulosic substrates obtained from different pretreatments have a big impact on downstream saccharification based on both the fungal cellulase system and the cellulosome-based whole-cell biocatalysis system. However the corresponding effect of these two distinct saccharification strategies has not been comparatively analyzed. In this work, three ammonium sulfite (AS)-based pretreatment combinations (i.e., AS + hydrothermal (HT) pretreatment, AS + xylanase (X) pretreatment, and HT + AS pretreatment) were conducted to treat wheat straw. The obtained pretreated substrates with different properties were saccharified using fungal cellulase or an engineered Clostridium thermocellum strain as the whole-cell biocatalyst, and the ability to release sugar was comparatively evaluated. It was found that for the whole-cell saccharification, the total sugar digestibility of AS + HT/X pretreated wheat straw was 10% higher than that of HT + AS pretreated wheat straw. However, for fungal cellulase-based saccharification, the enzymatic hydrolysis efficiency was less susceptible to the sequence of pretreatment combinations. Hence, the whole-cell biocatalysis system was more sensitive to substrate accessibility compared to the free enzymes. In addition, the characterization and analyses showed that AS + HT/X pretreatment could remove more lignin, generating a more accessible surface with a larger external surface and lower surface lignin coverage, compared to the HT + AS pretreatment. Therefore, the AS + HT/X pretreatment was more compatible with the cellulosome-based whole-cell saccharification.

11.
ACS Omega ; 4(5): 9074-9080, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459995

RESUMO

Fluorescent probes physisorbed on nanomaterials have emerged as a kind of useful and facile sensing platform for biological important molecules. However, nonspecific displacement in the physisorption systems is a non-negligible problem for the intracellular analysis. MIL (Materials of Institut Lavoisier), a subclass of metal-organic frameworks (MOFs), has high porosity, large surface area, and intriguing three-dimensional (3D) nanostructure with promising biological and biomedical applications such as molecular detection and drug delivery. Herein, we report MIL/aptamer-FAM as a nanosensor capable of resisting nonspecific displacement for intracellular adenosinetriphosphate (ATP) sensing and imaging. In this approach, by virtue of the remarkable quenching capability, high affinity of aptamers, and dramatic capability of resisting nonspecific displacement of 3D MIL-100, the assay and imaging of ATP in living cells were realized. Our results demonstrated that the MIL/aptamer-FAM nanosensor not only shows high selectivity for the detection of ATP in buffer but also is able to act as a "signal-on" nanosensor for specific imaging of ATP in living cells. The strategy reported here opens up a new way to develop MOF-based nanosensors for intracellular delivery and metabolite detection.

12.
Commun Biol ; 2: 267, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31341966

RESUMO

PCR amplification of Hi-C libraries introduces unusable duplicates and results in a biased representation of chromatin interactions. We present a simplified, fast, and economically efficient Hi-C library preparation procedure, SAFE Hi-C, which generates sufficient non-amplified ligation products for deep sequencing from 30 million Drosophila cells. Comprehensive analysis of the resulting data shows that amplification-free Hi-C preserves higher complexity of chromatin interaction and lowers sequencing depth for the same number of unique paired reads. For human cells which have a large genome, SAFE Hi-C recovers enough ligated fragments for direct high-throughput sequencing without amplification from as few as 250,000 cells. Comparison with published in situ Hi-C data from millions of human cells demonstrates that amplification introduces distance-dependent amplification bias, which results in an increased background noise level against genomic distance. With amplification bias avoided, SAFE Hi-C may produce a chromatin interaction network more faithfully reflecting the real three-dimensional genomic architecture.


Assuntos
Cromatina/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Animais , Drosophila/genética , Genômica , Humanos , Reação em Cadeia da Polimerase/métodos , Mapas de Interação de Proteínas , Globinas beta/genética
13.
Genomics Proteomics Bioinformatics ; 17(2): 140-153, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31201999

RESUMO

Enhancers activate transcription in a distance-, orientation-, and position-independent manner, which makes them difficult to be identified. Self-transcribing active regulatory region sequencing (STARR-seq) measures the enhancer activity of millions of DNA fragments in parallel. Here we used STARR-seq to generate a quantitative global map of rice enhancers. Most enhancers were mapped within genes, especially at the 5' untranslated regions (5'UTR) and in coding sequences. Enhancers were also frequently mapped proximal to silent and lowly-expressed genes in transposable element (TE)-rich regions. Analysis of the epigenetic features of enhancers at their endogenous loci revealed that most enhancers do not co-localize with DNase I hypersensitive sites (DHSs) and lack the enhancer mark of histone modification H3K4me1. Clustering analysis of enhancers according to their epigenetic marks revealed that about 40% of identified enhancers carried one or more epigenetic marks. Repressive H3K27me3 was frequently enriched with positive marks, H3K4me3 and/or H3K27ac, which together label enhancers. Intergenic enhancers were also predicted based on the location of DHS regions relative to genes, which overlap poorly with STARR-seq enhancers. In summary, we quantitatively identified enhancers by functional analysis in the genome of rice, an important model plant. This work provides a valuable resource for further mechanistic studies in different biological contexts.


Assuntos
Elementos Facilitadores Genéticos , Genômica/métodos , Oryza/genética , Análise de Sequência de DNA , Transcrição Gênica , Acetilação , Sequência de Bases , Desoxirribonuclease I/metabolismo , Epigênese Genética , Genes de Plantas , Código das Histonas/genética , Histonas/metabolismo , Modelos Genéticos , Regiões Promotoras Genéticas/genética , Sequências Repetitivas de Ácido Nucleico/genética
14.
Int J Mol Med ; 43(2): 1049-1057, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30483747

RESUMO

The upregulation of long non­coding RNA (lncRNA) human ovarian cancer­specific transcript 2 (HOST2) has been identified in breast cancer. The present study aimed to investigate whether lncRNA HOST2 regulated the proliferation of triple negative breast cancer (TNBC) cells, and the underlying molecular mechanism. In total, 30 patients with primary TNBC, who were treated at Wuhai People's Hospital (Wuhai, China), were recruited for the present study. Reverse transcription­quantitative polymerase chain reaction analysis was used for the examination of gene expression levels. A Cell Counting kit­8 (CCK­8) assay was used for the detection of cell proliferation. Phases of the cell cycle were evaluated by flow cytometry. Western blot analysis was performed to detect protein expression levels. A dual luciferase activity assay was performed to examine the interaction between microRNA (miRNA) and the 3' untranslated region (UTR) of target mRNA. The results revealed increased expression levels of HOST2 in tumor tissues from patients with TNBC. A positive correlation was identified between the expression of HOST2 and cyclin­dependent kinase 6 (CDK6) in tumor tissues. The silencing of HOST2 induced cell proliferation inhibition and cell cycle redistribution in MDA­MB­231 and MDA­MB­468 TNBC cells. In these two cell lines, HOST2 silencing caused a decrease in the phosphorylation of RB1 and CDK6, which was observed at the mRNA and protein levels. However, the silencing of CDK6 did not alter the expression of HOST2. It was hypothesized and confirmed that let­7b, a previously reported target miRNA of HOST2, was able to directly bind to the 3'UTR of CDK6 and repress its expression. The expression of let­7b was negatively correlated with the expression of HOST2 and CDK6 in tumor tissues. Overall, the data suggested that lncRNA HOST2 acts as an oncogene in TNBC via the upregulation of CDK6.


Assuntos
Quinase 6 Dependente de Ciclina/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , RNA Longo não Codificante/genética , Neoplasias de Mama Triplo Negativas/genética , Regiões 3' não Traduzidas , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Biologia Computacional/métodos , Quinase 6 Dependente de Ciclina/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Inativação Gênica , Humanos , Estadiamento de Neoplasias , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral
15.
J Orthop Sci ; 24(1): 42-49, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30219602

RESUMO

BACKGROUND: Dyslipidaemia is a well-known risk factor for the development of atherosclerosis, however, little is known about the effect of dyslipidaemia on intervertebral disc degeneration (IVDD). Thus, the purpose of this study is to investigate the relationship between dyslipidaemia and IVDD, and to identify the possible mechanism by which dyslipidaemia aggravates the degeneration of intervertebral discs. METHODS: Hyperlipidaemia rats were induced, thirty male Wistar rats were randomly divided into two groups: normal chow diet control group (CON) and high-fat diet group (HFD) for 8 weeks. And then, a rat disc degeneration model was established, rats were divided into three experimental groups: the normal chow diet + sham surgery group (CON-Sham); the normal chow diet + needle puncture group (CON-NP); and the high-fat diet + needle puncture group (HFD-NP), all rats were continually fed with normal chow diet or HFD 8 weeks. At the end of the experiment, the discs were harvested and histomorphological analysis, immunohistochemistry staining, real-time PCR and western blot were performed for all groups. RESULTS: The degenerative histological score of disc in the HFD-NP group was significantly higher than the CON-NP group. Immunohistochemical analysis revealed remarkable reductions in aggrecan and collagen type II expressions, and significant increases in IL-1ß, TNF-α, MMP-13, HIF-1α and P65 expression in the HFD-NP group. RT-PCR and western blot analysis showed that the mRNA levels and protein expressions of MMP-13 and TIMP-1 were higher in the HFD-NP group. CONCLUSIONS: Hyperlipidaemia resulted in an exaggerated degenerative changes and altered expression and transcription of the degeneration-associated molecules in the rat disc tissue. These results raise the possibility that hyperlipidaemia may accelerate the progression of disc degeneration.


Assuntos
Cóccix/lesões , Hiperlipidemias/complicações , Degeneração do Disco Intervertebral/etiologia , Disco Intervertebral/diagnóstico por imagem , Animais , Biópsia , Cóccix/diagnóstico por imagem , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hiperlipidemias/diagnóstico , Hiperlipidemias/metabolismo , Imuno-Histoquímica , Degeneração do Disco Intervertebral/diagnóstico , Degeneração do Disco Intervertebral/metabolismo , Reação em Cadeia da Polimerase , Prognóstico , RNA/genética , Ratos , Ratos Wistar
16.
RSC Adv ; 9(20): 11558-11566, 2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35520263

RESUMO

Corncob residue (CCR) is an economic feedstock with enormous potential for the production of bioethanol. In this work, potassium hydroxide (KOH) pretreatment of CCR was investigated under relatively mild conditions, and the effectiveness of KOH pretreatment was evaluated by enzymatic saccharification at high solid loading. Results showed that after KOH pretreatment (16 wt% KOH dosage at 70 °C for 90 min) and the enzymatic hydrolysis at 20% solids loading and 20 FPU g-1-substrate of cellulase loading, the glucose yield could reach up to about 91%, which was over 90% higher compared to the raw CCR without KOH pretreatment. Correspondingly, about 89% of lignin and 79% of extractives were removed after KOH pretreatment. In addition, the spent liquor of KOH pretreatment containing sylvite could be used as lignin-based fertilizer based on the concept of biorefinery. In this case, the entire process for the production of fermentable sugars was clean and sustainable, which is very vital for the conversion of lignocelluloses to bioenergy or chemicals.

17.
Biomaterials ; 185: 301-309, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30265899

RESUMO

Hypoxia tumor microenvironment is a major challenge for photodynamical therapy (PDT), and hypoxia-activated chemotherapy combined PDT could be promising for enhanced anticancer therapy. In this study, we report an innovative 2-nitroimidazole derivative conjugated polyethylene glycol (PEG) amphoteric polymer theranostic liposome encapsulated a photosensitizer Chlorin e6 (Ce6), hypoxia-activated prodrug Tirapazamine (TPZ) and gene probe for synergistic photodynamic-chemotherapy. Ce6-mediated PDT upon irradiation with a laser induces hypoxia, which leads to the disassembly of the liposome and activates the antitumor activity of TPZ for improved cancer cell-killing. The released co-delivered gene probe could effectively detect the oncogenic intracellular biomarker for diagnosis. Both in vitro and in vivo studies demonstrated the greatly improved anti-cancer activity compared to conventional PDT. This work contributes to the design of hypoxia-responsive multifunctional liposome for tumor diagnosis and hypoxia-activated chemotherapy combined PDT for synergetic therapy, which holds great promise for future cancer therapy.


Assuntos
Lipossomos/química , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Nitroimidazóis/química , Fármacos Fotossensibilizantes/administração & dosagem , Porfirinas/administração & dosagem , Tirapazamina/administração & dosagem , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Clorofilídeos , Preparações de Ação Retardada/química , Humanos , Luz , Células MCF-7 , Camundongos , Imagem Óptica , Fármacos Fotossensibilizantes/uso terapêutico , Polietilenoglicóis/química , Porfirinas/uso terapêutico , Nanomedicina Teranóstica , Tirapazamina/uso terapêutico , Hipóxia Tumoral/efeitos dos fármacos
18.
Inflammation ; 40(3): 946-955, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28247166

RESUMO

The aim of this study was to investigate progranulin (PGRN) expression and its effect in cartilage degradation and in the pathogenesis of osteonecrosis of the femoral head (ONFH). Cartilage specimens were obtained from ONFH and FNF patients and PGRN expression was analyzed by immunohistochemistry, western blot analysis, and RT-PCR. Peripheral blood PGRN level was detected by ELISA. Additionally, primary chondrocytes were cultured and treated with PGRN. Next, the expression of aggrecan and collagen II and the activation of ERK1/2 were detected. We observed that the expression of PGRN was significantly upregulated in ONFH patients' articular cartilage, and recombinant PGRN could promote expression of aggrecan and collagen II and the activation of ERK1/2. Collectively, PGRN can improve chondrocyte anabolism and perform a therapeutic role in the pathogenesis of ONFH. This study helps to elucidate the pathogenesis of ONFH and presents PGRN as a potential target for the treatment of ONFH.


Assuntos
Cabeça do Fêmur/patologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Osteonecrose/prevenção & controle , Agrecanas/metabolismo , Cartilagem Articular , Células Cultivadas , Condrócitos/metabolismo , Colágeno/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Progranulinas , Substâncias Protetoras/farmacologia
19.
Carbohydr Polym ; 151: 716-724, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27474618

RESUMO

In this work, nanocellulose was extracted from bleached corncob residue (CCR), an underutilized lignocellulose waste from furfural industry, using four different methods (i.e. sulfuric acid hydrolysis, formic acid (FA) hydrolysis, 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation, and pulp refining, respectively). The self-assembled structure, morphology, dimension, crystallinity, chemical structure and thermal stability of prepared nanocellulose were investigated. FA hydrolysis produced longer cellulose nanocrystals (CNCs) than the one obtained by sulfuric acid hydrolysis, and resulted in high crystallinity and thermal stability due to its preferential degradation of amorphous cellulose and lignin. The cellulose nanofibrils (CNFs) with fine and individualized structure could be isolated by TEMPO-mediated oxidation. In comparison with other nanocellulose products, the intensive pulp refining led to the CNFs with the longest length and the thickest diameter. This comparative study can help to provide an insight into the utilization of CCR as a potential source for nanocellulose production.


Assuntos
Celulose/química , Celulose/isolamento & purificação , Formiatos/química , Fenômenos Mecânicos , Nanoestruturas/química , Ácidos Sulfúricos/química , Zea mays/química , Nanotecnologia , Oxirredução , Temperatura
20.
Int J Biol Macromol ; 88: 451-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27064089

RESUMO

The hemicellulose isolated from the spent liquor of a viscose process was successfully utilized to prepare hydrogels by the graft copolymerization of acrylic acid (AA) with hemicellulose. The hemicellulose and prepared hydrogel were characterized by Fourier-transform infrared (FT-IR), scanning electron microscopy (SEM), and solid-state nuclear magnetic resonance ((13)C NMR). Under the optimum preparation conditions, the highest compressive strength and strain at break of the resultant hydrogel were 105.1±12.9kPa and 34.8%, respectively. Furthermore, the maximum equilibrium swelling degree of prepared hydrogel was 192. Also, the hydrogel could rapidly respond to pH, salt and ethanol. Taken together, the prepared hydrogels had great mechanical and multi-responsive properties. Thus, the prepared hydrogels had a great potential application in drug release, water treatment and cell immobilization. In addition, the utilization of alkaline extracted hemicellulose from the viscose fiber factory has huge market potential and economic benefits.


Assuntos
Acrilatos/química , Portadores de Fármacos/química , Polímeros/química , Polissacarídeos/química , Acrilatos/síntese química , Celulose/química , Portadores de Fármacos/síntese química , Liberação Controlada de Fármacos , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/administração & dosagem , Hidrogel de Polietilenoglicol-Dimetacrilato/síntese química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Microscopia Eletrônica de Varredura , Polimerização , Polímeros/síntese química , Polissacarídeos/síntese química
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