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1.
Neurobiol Dis ; 180: 106105, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36977454

RESUMO

Parkinson's disease (PD) is the most common neurodegenerative movement disorder, characterized by the progressive loss of nigrostriatal dopaminergic neurons (DANs), involving the dysregulation of both neurons and glial cells. Cell type- and region-specific gene expression profiles can provide an effective source for revealing the mechanisms of PD. In this study, we adopted the RiboTag approach to obtain cell type (DAN, microglia, astrocytes)- and brain region (substantia nigra, caudate-putamen)-specific translatomes at an early stage in an MPTP-induced mouse model of PD. Through DAN-specific translatome analysis, the glycosphingolipid biosynthetic process was identified as a significantly downregulated pathway in the MPTP-treated mice. ST8Sia6, a key downregulated gene related to glycosphingolipid biosynthesis, was confirmed to be downregulated in nigral DANs from postmortem brains of patients with PD. Specific expression of ST8Sia6 in DANs exerts anti-inflammatory and neuroprotective effects in MPTP-treated mice. Through cell type (microglia vs. astrocyte) and brain region (substantia nigra vs. caudate-putamen) comparisons, nigral microglia showed the most intense immune responses. Microglia and astrocytes in the substantia nigra showed similar levels of activation in interferon-related pathways and interferon gamma (IFNG) was identified as the top upstream regulator in both cell types. This work highlights that the glycosphingolipid metabolism pathway in the DAN is involved in neuroinflammation and neurodegeneration in an MPTP mouse model of PD and provides a new data source for elucidating the pathogenesis of PD.


Assuntos
Intoxicação por MPTP , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/metabolismo , Microglia/metabolismo , Doenças Neurodegenerativas/metabolismo , Fármacos Neuroprotetores/farmacologia , Glicoesfingolipídeos/metabolismo , Camundongos Endogâmicos C57BL , Neurônios Dopaminérgicos/metabolismo , Modelos Animais de Doenças , Substância Negra/metabolismo , Intoxicação por MPTP/patologia
2.
Small ; 19(47): e2303959, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37496085

RESUMO

Metallic sodium is regarded as the most potential anode for sodium-ion batteries due to its high capacity and earth-abundancy. Nevertheless, uncontrolled Na dendrite growth and infinite volume change remain great challenges for developing high-performance sodium metal batteries. This work provides a simple and general approach to stabilize sodium metal anode (SMA) by constructing Sn nanoparticles-anchored laser-induced graphene on copper foil (Sn@LIG@Cu) consisting of Sn@LIG composite, polyimide (PI) columns, and Cu current collector. The Sn-based sodiophilic species effectively reduce the Na nucleation overpotential and regulate the dendrite Na-free deposition. While the flexible PI columns act as binder and buffer the volume variation of Na during cycling. Besides, the unique patterned structure provides continuous and rapid channels for ion transportation, promoting the Na+ transport kinetics. Therefore, the as-fabricated Sn@LIG@Cu electrode exhibits outstanding rate performance to 40 mA cm-2 and excellent cycling stability without dendrite growth, which is confirmed by in-situ optical microscopy observation. Moreover, the practical full cell based on such an anode displays a favorable rate capability of up to 10 C and cycling performance at 5 C for 600 cycles. This work thus demonstrates a facile, highly-efficient, and scalable approach to stabilize SMAs and can be extended to other battery systems.

3.
Phys Rev Lett ; 129(27): 276601, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36638296

RESUMO

The discovery of hidden spin polarization (HSP) in centrosymmetric nonmagnetic crystals, i.e., spatially distributed spin polarization originated from local symmetry breaking, has promised an expanded material pool for future spintronics. However, the measurements of such exotic effects have been limited to subtle space- and momentum-resolved techniques, unfortunately, hindering their applications. Here, we theoretically predict macroscopic non-reciprocal transports induced by HSP when coupling another spatially distributed quantity, such as staggered local moments in a space-time PT-symmetric antiferromagnet. By using a four-band model Hamiltonian, we demonstrate that HSP plays a crucial role in determining the asymmetric bands with respect to opposite momenta. Such band asymmetry leads to non-reciprocal nonlinear conductivity, exemplified by tetragonal CuMnAs via first-principles calculations. We further provide the material design principles for large nonlinear conductivity, including two-dimensional nature, multiple band crossings near the Fermi level, and symmetry protected HSP. Our Letter not only reveals direct spintronic applications of HSP (such as Néel order detection), but also sheds light on finding observables of other hidden effects, such as hidden optical polarization and hidden Berry curvature.

4.
HPB (Oxford) ; 24(12): 2175-2184, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36280426

RESUMO

BACKGROUND: It is unclear whether associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) can be performed in hepatitis B virus-related hepatocellular carcinoma (HCC) patients with cirrhosis. We explored the efficacy of ALPPS in HCC patients. METHODS: Data of 54 patients who underwent ALPPS between August 2014 and July 2020 at three centers were collected. Adverse factors affecting their prognosis were analyzed and subsequently compared with 184 patients who underwent transcatheter arterial chemoembolization (TACE). RESULTS: Overall survival rates of the ALPPS group at 1, 3, and 5 years were 70.6%, 38.4%, and 31.7%, respectively; corresponding disease-free survival rates were 50.5%, 22.4%, and 19.2%, respectively. The ALPPS group had a significantly greater long-term survival rate than the TACE group (before propensity score matching, P < 0.001; after propensity score matching, P = 0.002). Multivariate analysis demonstrated that multifocal lesions (P = 0.018) and macroscopic vascular invasion (P = 0.001) were prognostic factors for HCC patients who underwent ALPPS. After the propensity score matching, the multifocal lesions (P = 0.031), macroscopic vascular invasion (P = 0.003), and treatment type (ALPPS/TACE) (P = 0.026) were the factors adversely affecting the prognosis of HCC patients. CONCLUSION: ALPPS was feasible in hepatitis B virus-related HCC patients with cirrhosis and resulted in better survival than TACE.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Veia Porta/cirurgia , Veia Porta/patologia , Vírus da Hepatite B , Quimioembolização Terapêutica/efeitos adversos , Resultado do Tratamento , Hepatectomia/efeitos adversos , Hepatectomia/métodos , Ligadura , Cirrose Hepática/patologia
5.
Natl Sci Rev ; 11(2): nwad066, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38213518

RESUMO

We review recent progress in the electronic structure study of intrinsic magnetic topological insulators (MnBi2Te4) · (Bi2Te3)n ([Formula: see text]) family. Specifically, we focus on the ubiquitously (nearly) gapless behavior of the topological Dirac surface state observed by photoemission spectroscopy, even though a large Dirac gap is expected because of surface ferromagnetic order. The dichotomy between experiment and theory concerning this gap behavior is perhaps the most critical and puzzling question in this frontier. We discuss various proposals accounting for the lack of magnetic effect on the topological Dirac surface state, which are mainly categorized into two pictures, magnetic reconfiguration and topological surface state redistribution. Band engineering towards opening a magnetic gap of topological surface states provides great opportunities to realize quantized topological transport and axion electrodynamics at higher temperatures.

6.
Front Oncol ; 14: 1372123, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628666

RESUMO

Background: Portal vein tumor thrombus (PVTT) seriously affects the prognosis of hepatocellular carcinoma (HCC). However, whether bile duct tumor thrombus (BDTT) significantly affects the prognosis of HCC as much as PVTT remains unclear. We aimed to compare the long-term surgical outcomes of HCC with macroscopic PVTT (macro-PVTT) and macroscopic BDTT (macro-BDTT). Methods: The data of HCC patients with macro-BDTT or macro-PVTT who underwent hemihepatectomy were retrospectively reviewed. A propensity score matching (PSM) analysis was performed to reduce the baseline imbalance. The recurrence-free survival (RFS) and overall survival (OS) rates were compared between the cohorts. Results: Before PSM, the PVTT group had worse RFS and OS rates than the BDTT group (P = 0.043 and P = 0.008, respectively). Multivariate analyses identified PVTT (hazard ratio [HR] = 1.835, P = 0.016) and large HCC (HR = 1.553, P = 0.039) as independent risk factors for poor OS and RFS, respectively. After PSM, the PVTT group had worse RFS and OS rates than the BDTT group (P = 0.037 and P = 0.004, respectively). The 3- and 5-year OS rates were significantly higher in the BDTT group (59.5% and 52.1%, respectively) than in the PVTT group (33.3% and 20.2%, respectively). Conclusion: Aggressive hemihepatectomy provides an acceptable prognosis for HCC patients with macro-BDTT. Furthermore, the long-term surgical outcomes of HCC patients with macro-BDTT were significantly better than those of HCC patients with macro-PVTT.

7.
Nat Commun ; 15(1): 2859, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570500

RESUMO

Cold-induced injuries severely limit opportunities and outcomes of hypothermic therapies and organ preservation, calling for better understanding of cold adaptation. Here, by surveying cold-altered chromatin accessibility and integrated CUT&Tag/RNA-seq analyses in human stem cells, we reveal forkhead box O1 (FOXO1) as a key transcription factor for autonomous cold adaptation. Accordingly, we find a nonconventional, temperature-sensitive FOXO1 transport mechanism involving the nuclear pore complex protein RANBP2, SUMO-modification of transporter proteins Importin-7 and Exportin-1, and a SUMO-interacting motif on FOXO1. Our conclusions are supported by cold survival experiments with human cell models and zebrafish larvae. Promoting FOXO1 nuclear entry by the Exportin-1 inhibitor KPT-330 enhances cold tolerance in pre-diabetic obese mice, and greatly prolongs the shelf-life of human and mouse pancreatic tissues and islets. Transplantation of mouse islets cold-stored for 14 days reestablishes normoglycemia in diabetic mice. Our findings uncover a regulatory network and potential therapeutic targets to boost spontaneous cold adaptation.


Assuntos
Diabetes Mellitus Experimental , Fatores de Transcrição Forkhead , Camundongos , Humanos , Animais , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Transporte Ativo do Núcleo Celular , Peixe-Zebra/metabolismo , Carioferinas/metabolismo
8.
ISA Trans ; 138: 254-261, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36797161

RESUMO

Abrupt-motion tracking is challenging due to the target's unpredictable action. Although particle filter (PF) is suitable for target tracking of nonlinear non-Gaussian systems, it suffers from the problems of particle impoverishment and sample-size dependency. This paper proposed a quantum-inspired particle filter for abrupt-motion tracking. We apply the concept of quantum superposition to transform classical particles into quantum particles. Quantum representation and corresponding quantum operations are addressed to utilize quantum particles. The superposition property of quantum particles avoids the concerns of particle impoverishment and sample-size dependency. The proposed diversity-preserving quantum-enhanced particle filter (DQPF) obtains better accuracy and stability with fewer particles. A smaller sample size also helps to reduce computational complexity. Moreover, it has significant advantages for abrupt-motion tracking. The quantum particles are propagated at the prediction stage. They will exist at possible places when abrupt motion occurs, which reduces the tracking delay and enhances the tracking accuracy. This paper conducted experiments compared to state-of-the-art particle filter algorithms. The numerical results demonstrate that the DQPF is not susceptible to motion mode and particle number. Meanwhile, DQPF maintains excellent accuracy and stability.

9.
J Hepatocell Carcinoma ; 10: 1799-1811, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37850080

RESUMO

Purpose: In recent years, immune checkpoint inhibitors have been used in combination with tyrosine kinase inhibitors and local therapies, creating a new era in treating hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). However, the benefits of this triple therapy remain unclear. Thus, this study evaluated whether the combination of transarterial chemoembolization (TACE), lenvatinib, and programmed death-1 (PD-1) inhibitors (triple therapy) was effective and safe for unresectable HCC with main trunk portal vein tumor thrombus (Vp4). Patients and Methods: This study enrolled patients receiving triple therapy at four institutions between August 2018 and April 2022. Patient characteristics and course of treatment were extracted from patient records. Tumors and tumor thrombus response were evaluated using an HCC-specific modified RECIST. Kaplan-Meier curve analysis demonstrated overall survival (OS) and progression-free survival (PFS). Adverse events (AEs) were evaluated according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 5.0. Results: Median follow-up duration was 18 (4.0-26.3) months. Overall, 41 patients with HCC and Vp4 receiving first-line triple therapy were enrolled. The intrahepatic tumor objective response rate was 68.3%. The median OS was 21.7 (range, 2.8-30.5) months, whereas the median PFS was 14.5 (range, 1.3-27.6) months. Twelve patients received sequential resections. Resection was independently associated with favorable OS and PFS. Fever (31.7%), hypertension (26.8%), fatigue (24.4%), abnormal liver function (63.4%) and decreased appetite (21.9%) were the AEs frequently associated with treatment. No treatment-related mortality occurred. Conclusion: TACE plus lenvatinib and PD-1 inhibition was effective and tolerable for treating unresectable HCC with Vp4, with a high tumor response rate and favorable prognosis.

10.
Front Oncol ; 13: 1291479, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38111530

RESUMO

Background: The long-term prognosis after surgery of patients with hepatocellular carcinoma (HCC) and extrahepatic bile duct tumor thrombus (Ex-BDTT) remains unknown. We aimed to identify the surgical outcomes of patients with HCC and Ex-BDTT. Methods: A total of 138 patients with Ex-BDTT who underwent hepatectomy with preservation of the extrahepatic bile duct from five large hospitals in China between January 2009 and December 2017 were included. The Cox proportional hazards model was used to analyze overall survival (OS) and recurrence-free survival (RFS). Results: With a median follow-up of 60 months (range, 1-127.8 months), the median OS and RFS of the patients were 28.6 and 8.9 months, respectively. The 1-, 3-, and 5-year OS rates of HCC patients with Ex-BDTT were 71.7%, 41.2%, and 33.5%, respectively, and the corresponding RFS rates were 43.5%, 21.7%, and 20.0%, respectively. Multivariate analysis identified that major hepatectomy, R0 resection, and major vascular invasion were independent prognostic factors for OS and RFS. In addition, preoperative serum total bilirubin ≥ 4.2 mg/dL was an independent prognostic factor for RFS. Conclusion: Major hepatectomy with preservation of the extrahepatic bile duct can provide favorable long-term survival for HCC patients with Ex-BDTT.

11.
J Ind Microbiol Biotechnol ; 39(9): 1301-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22569922

RESUMO

An effective approach to greatly enhancing the selective secretion and expression of recombinant cytoplasmic enzymes in Escherichia coli was successfully developed through the synergistic effect of ethylenediaminetetraacetate (EDTA) and lysozyme. The method was applied to two endoglucanases (EGs) and an amylase. The optimal culture conditions of temperature and concentration of isopropyl-ß-D: -1-thiogalactopyranoside (IPTG) were 23-30 °C and 0.2 mM, respectively, under which the three enzymes could be expressed in active form. Among all the chemicals tested, EDTA was found to be most suitable for enhancing the secretion of EG-I-1A into the medium. Addition of lysozyme alone had little influence on the secretion and expression. In contrast, on the basis of the addition of 5 g EDTA/L at the induction time of 12 h, the simultaneous addition of 0.15 g lysozyme/L further significantly increased the secretion and expression of the three enzymes, demonstrating the synergistic effect of EDTA and lysozyme. The production of EG-I-1A in the culture medium by adding 5 g EDTA/L and 0.15 g lysozyme/L under the optimal culture conditions of 23 °C and 0.2 mM IPTG was over 260-fold higher than that without EDTA and lysozyme under the standard conditions of 37 °C and 1 mM IPTG. In summary, the advantage of this novel cultivation approach for secretion was that not only did it selectively enhance the secretion of the proteins of interest, but also greatly increased the expression of the three enzymes by over 80 %.


Assuntos
Amilases/biossíntese , Celulase/biossíntese , Ácido Edético/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Muramidase/farmacologia , Amilases/genética , Amilases/metabolismo , Bacillus/enzimologia , Bacillus/genética , Celulase/genética , Celulase/metabolismo , Meios de Cultura/química , Meios de Cultura/farmacologia , Escherichia coli/citologia , Muramidase/metabolismo
12.
ACS Synth Biol ; 11(10): 3134-3153, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36094344

RESUMO

Intestinal probiotics are often used for the in situ treatment of diseases, such as metabolic disorders, tumors, and chronic inflammatory infections. Recently, there has been an increased emphasis on intelligent, customized treatments with a focus on long-term efficacy; however, traditional probiotic therapy has not kept up with this trend. The use of synthetic biology to construct gut-engineered probiotics as live therapeutics is a promising avenue in the treatment of specific diseases, such as phenylketonuria and inflammatory bowel disease. These studies generally involve a series of fundamental design issues: choosing an engineered chassis, improving the colonization ability of engineered probiotics, designing functional gene circuits, and ensuring the safety of engineered probiotics. In this review, we summarize the relevant past research, the progress of current research, and discuss the key issues that restrict the widespread application of intestinal engineered probiotic living therapeutics.


Assuntos
Doenças Inflamatórias Intestinais , Doenças Metabólicas , Probióticos , Humanos , Redes Reguladoras de Genes , Probióticos/uso terapêutico , Biologia Sintética
13.
Elife ; 112022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35535997

RESUMO

Lineage reprogramming of resident glial cells to dopaminergic neurons (DAns) is an attractive prospect of the cell-replacement therapy for Parkinson's disease (PD). However, it is unclear whether repressing polypyrimidine tract binding protein 1 (PTBP1) could efficiently convert astrocyte to DAns in the substantia nigra and striatum. Although reporter-positive DAns were observed in both groups after delivering the adeno-associated virus (AAV) expressing a reporter with shRNA or CRISPR-CasRx to repress astroglial PTBP1, the possibility of AAV leaking into endogenous DAns could not be excluded without using a reliable lineage-tracing method. By adopting stringent lineage-tracing strategy, two other studies show that either knockdown or genetic deletion of quiescent astroglial PTBP1 fails to obtain induced DAns under physiological condition. However, the role of reactive astrocytes might be underestimated because upon brain injury, reactive astrocyte can acquire certain stem cell hallmarks that may facilitate the lineage conversion process. Therefore, whether reactive astrocytes could be genuinely converted to DAns after PTBP1 repression in a PD model needs further validation. In this study, we used Aldh1l1-CreERT2-mediated specific astrocyte-lineage-tracing method to investigate whether reactive astrocytes could be converted to DAns in a 6-hydroxydopamine (6-OHDA) mouse model of PD. However, we found that no astrocyte-originated DAn was generated after effective and persistent knockdown of astroglial PTBP1 either in the substantia nigra or in striatum, while AAV 'leakage' to nearby neurons was easily observed. Our results confirm that repressing PTBP1 does not convert astrocytes to DAns, regardless of physiological or PD-related pathological conditions.


Assuntos
Neurônios Dopaminérgicos , Doença de Parkinson , Animais , Astrócitos/metabolismo , Dependovirus/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Camundongos , Oxidopamina/metabolismo , Oxidopamina/farmacologia , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Substância Negra
14.
PLoS One ; 17(10): e0274522, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36256637

RESUMO

A high-performance medical image segmentation model based on deep learning depends on the availability of large amounts of annotated training data. However, it is not trivial to obtain sufficient annotated medical images. Generally, the small size of most tissue lesions, e.g., pulmonary nodules and liver tumours, could worsen the class imbalance problem in medical image segmentation. In this study, we propose a multidimensional data augmentation method combining affine transform and random oversampling. The training data is first expanded by affine transformation combined with random oversampling to improve the prior data distribution of small objects and the diversity of samples. Secondly, class weight balancing is used to avoid having biased networks since the number of background pixels is much higher than the lesion pixels. The class imbalance problem is solved by utilizing weighted cross-entropy loss function during the training of the CNN model. The LUNA16 and LiTS17 datasets were introduced to evaluate the performance of our works, where four deep neural network models, Mask-RCNN, U-Net, SegNet and DeepLabv3+, were adopted for small tissue lesion segmentation in CT images. In addition, the small tissue segmentation performance of the four different deep learning architectures on both datasets could be greatly improved by incorporating the data augmentation strategy. The best pixelwise segmentation performance for both pulmonary nodules and liver tumours was obtained by the Mask-RCNN model, with DSC values of 0.829 and 0.879, respectively, which were similar to those of state-of-the-art methods.


Assuntos
Neoplasias Hepáticas , Nódulos Pulmonares Múltiplos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação
15.
J Ind Microbiol Biotechnol ; 38(7): 855-61, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21298463

RESUMO

An alkaline endoglucanase from Bacillus akibai III-3A was successfully expressed in Escherichia coli in active form, and secretion was greatly enhanced by addition of 5 g/l ethylenediamine tetraacetic acid (EDTA) to the culture medium at the induction time of 12 h. Under the optimal culture conditions, extracellular and total endoglucanase activities were 18.5 and 31.2 U/ml, respectively. Both the recombinant and native enzymes exhibited similar properties with respect to broad pH stability, good thermostability, and resistibility to various metal ions and reagents examined. However, unlike the native endoglucanase that was partly inhibited by sodium dodecyl sulfate (SDS), the recombinant enzyme had good resistibility to SDS, being very stable in the commercial detergents, and no decrease in residual activity was observed in 0.2% (w/v) laundry detergent, indicating that it was suitable for application in detergents industry.


Assuntos
Proteínas de Bactérias/genética , Celulase/genética , Escherichia coli/genética , Proteínas Recombinantes/metabolismo , Sequência de Aminoácidos , Bacillus/enzimologia , Bacillus/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Celulase/química , Celulase/metabolismo , Clonagem Molecular , Detergentes/química , Ácido Edético/farmacologia , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Proteínas Recombinantes/isolamento & purificação , Dodecilsulfato de Sódio/química
16.
Synth Syst Biotechnol ; 6(4): 437-445, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34901482

RESUMO

The invasive plant Mikania micrantha Kunth (M. micrantha) from South America poses a significant threat to the stability and biodiversity of ecosystems. However, an effective and economical method to control M. micrantha is still lacking. RNA interference (RNAi) has been widely studied and applied in agriculture for trait improvement. Spray-induced gene silencing (SIGS) can produce RNAi silencing effects without introducing heritable modifications to the plant genome and is becoming a novel nontransformation strategy for plant protection. In this study, the genes encoding chlorophyll a/b-binding proteins were selected as targets of RNAi, based on high-throughput sequencing of M. micrantha transcriptome and bioinformatic analyses of sequence specificity. Three types of RNAi molecules, double-stranded RNA, RNAi nanomicrosphere, and short hairpin RNA (shRNA), with their corresponding short interfering RNA sequences were designed and synthesized for SIGS vector construction, from which each RNAi molecule was transcribed and extracted to be sprayed on M. micrantha leaves. Whereas water-treated control leaves remained green, leaves treated with RNAi molecules turned yellow and eventually wilted. Quantitative real-time PCR showed that the expression levels of target genes were significantly reduced in the RNAi-treated groups compared with those of the control, suggesting that all three types of RNAi herbicides effectively silenced the endogenous target genes, which are essential for the growth of M. micrantha. We also found that shRNA showed better silencing efficiency than the other two molecules. Taken together, our study successfully designed three types of RNAi-based herbicides that specifically silenced endogenous target genes and controlled the growth of M. micrantha. Moreover, we identified a gene family encoding chlorophyll a/b-binding proteins that is important for the growth and development of M. micrantha and could serve as potential targets for controlling the spread of M. micrantha.

17.
Synth Syst Biotechnol ; 6(3): 216-223, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34504963

RESUMO

Gardenia blue is a natural blue pigment that is environmentally friendly, non-toxic, and stable. The hydrolysis of geniposide, catalyzed by ß-glucosidase, is a critical step in the production process of gardenia blue. However, ß-glucosidase is not resistant to high temperatures, limiting the production of gardenia blue. In this study, we investigated the effectiveness of a heat-resistant glucosidase obtained from Thermotoga maritima in the production of gardenia blue. The enzyme exhibited a maximum activity of 10.60 U/mL at 90 °C. Single-factor and orthogonal analyses showed that exogenously expressed heat-resistant glucosidase reacted with 470.3 µg/mL geniposide and 13.5 µg/mL glycine at 94.2 °C, producing a maximum yield of 26.2857 µg/mL of gardenia blue after 156.6 min. When applied to the dyeing of denim, gardenia blue produced by this method yielded excellent results; the best color-fastness was achieved when an iron ion mordant was used. This study revealed the feasibility and application potential of microbial production of gardenia blue.

18.
World J Clin Cases ; 9(8): 1803-1813, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33748229

RESUMO

BACKGROUND: Laparoscopic cholecystectomy (LC) combined with laparoscopic common bile duct (CBD) exploration (LCBDE) is one of the main treatments for choledocholithiasis with CBD diameter of larger than 10 mm. However, for patients with small CBD (CBD diameter ≤ 8 mm), endoscopic sphincterotomy remains the preferred treatment at present, but it also has some drawbacks associated with a series of complications, such as pancreatitis, hemorrhage, cholangitis, and duodenal perforation. To date, few studies have been reported that support the feasibility and safety of LCBDE for choledocholithiasis with small CBD. AIM: To investigate the feasibility and safety of LCBDE for choledocholithiasis with small CBD. METHODS: A total of 257 patients without acute cholangitis who underwent LC + LCBDE for cholecystolithiasis from January 2013 to December 2018 in one institution were reviewed. The clinical data were retrospectively collected and analyzed. According to whether the diameter of CBD was larger than 8 mm, 257 patients were divided into large CBD group (n = 146) and small CBD group (n = 111). Propensity score matching (1:1) was performed to adjust for clinical differences. The demographics, intraoperative data, short-term outcomes, and long-term follow-up outcomes for the patients were recorded and compared. RESULTS: In total, 257 patients who underwent successful LC + LCBDE were enrolled in the study, 146 had large CBD and 111 had small CBD. The median follow-up period was 39 (14-86) mo. For small CBD patients, the median CBD diameter was 0.6 cm (0.2-2.0 cm), the mean operating time was 107.2 ± 28.3 min, and the postoperative bile leak rate, rate of residual CBD stones (CBDS), CBDS recurrence rate, and CBD stenosis rate were 5.41% (6/111), 3.60% (4/111), 1.80% (2/111), and 0% (0/111), respectively; the mean postoperative hospital stay was 7.4 ± 3.6 d. For large CBD patients, the median common bile duct diameter was 1.0 cm (0.3-3.0 cm), the mean operating time was 115.7 ± 32.0 min, and the postoperative bile leak rate, rate of residual CBDS, CBDS recurrence rate, and CBD stenosis rate were 5.41% (9/146), 1.37% (2/146), 6.85% (10/146), and 0% (0/146), respectively; the mean postoperative hospital stay was 7.7 ± 2.7 d. After propensity score matching, 184 patients remained, and all preoperative covariates except diameter of CBD stones were balanced. Postoperative bile leak occurred in 11 patients overall (5.98%), and no difference was found between the small CBD group (4.35%, 4/92) and the large CBD group (7.61%, 7/92). The incidence of CBDS recurrence did not differ significantly between the small CBD group (2.17%, 2/92) and the large CBD group (6.52%, 6/92). CONCLUSION: LC + LCBDE is safe and feasible for choledocholithiasis patients with small CBD and did not increase the postoperative bile leak rate compared with chole-docholithiasis patients with large CBD.

19.
ACS Chem Neurosci ; 10(2): 839-851, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30346716

RESUMO

Parkinson's disease (PD) is a chronic progressive neurodegenerative disorder symptomatically characterized by resting tremor, rigidity, bradykinesia, and gait impairment. These motor deficits suffered by PD patients primarily result from selective dysfunction or loss of dopaminergic neurons of the substantia nigra pars compacta (SNpc). Most of the existing therapies for PD are based on the replacement of dopamine, which is symptomatically effective in the early stage but becomes increasingly less effective and is accompanied by serious side effects in the advanced stages of the disease. Currently, there are no strategies to slow neuronal degeneration or prevent the progression of PD. Thus, the prospect of regenerating functional dopaminergic neurons is very attractive. Over the last few decades, significant progress has been made in the development of dopaminergic regenerative strategies for curing PD. The most promising approach seems to be cell-replacement therapy (CRT) using human embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs), which are unlimitedly available and have gained much success in preclinical trials. Despite the challenges, stem cell-based CRT will make significant steps toward the clinic in the coming decade. Alternatively, direct lineage reprogramming, especially in situ direct conversion of glia cells to induced neurons, which exhibits some advantages including no ethical concerns, no risk of tumor formation, and even no need for transplantation, has gained much attention recently. Evoking the endogenous regeneration ability of neural stem cells (NSCs) is an idyllic method of dopaminergic neuroregeneration which remains highly controversial. Here, we review many of these advances, highlighting areas and strategies that might be particularly suited to the development of regenerative approaches that restore dopaminergic function in PD.


Assuntos
Neurônios Dopaminérgicos/transplante , Células-Tronco Embrionárias/transplante , Regeneração Nervosa/fisiologia , Células-Tronco Neurais/transplante , Doença de Parkinson/terapia , Transplante de Células-Tronco/métodos , Animais , Neurônios Dopaminérgicos/fisiologia , Células-Tronco Embrionárias/fisiologia , Humanos , Células-Tronco Pluripotentes Induzidas/transplante , Células-Tronco Neurais/fisiologia , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Transplante de Células-Tronco/tendências
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