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1.
J Dent Sci ; 19(2): 1116-1125, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38618055

RESUMEN

Background/purpose: 3D-printed bone tissue engineering is becoming recognized as a key approach in dentistry for creating customized bone regeneration treatments fitting patients bone defects requirements. 3D bioprinting offers an innovative method to fabricate detailed 3D structures, closely emulating the native bone micro-environment and better bone regeneration. This study aimed to develop an 3D-bioprintable scaffold using a combination of alginate and ß-tricalcium phosphate (ß-TCP) with the Cellink® BioX printer, aiming to advance the field of tissue engineering. Materials and methods: The physical and biological properties of the resulting 3D-printed scaffolds were evaluated at 10 %, 12 %, and 15 % alginate combined with 10 % ß-TCP. The scaffolds were characterized through printability, swelling behavior, degradability, and element analysis. The biological assessment included cell viability, alkaline phosphatase (ALP) activity. Results: 10 % alginate/ß-TCP 3D printed at 25 °C scaffold demonstrated the optimal condition for printability, swelling capability, and degradability of cell growth and nutrient diffusion. Addition of ß-TCP particles significantly improved the 3D printed material viscosity over only alginate (P < 0.05). 10 % alginate/ß-TCP enhanced MG-63 cell's proliferation (P < 0.05) and alkaline phosphatase activity (P < 0.001). Conclusion: This study demonstrated in vitro that 10 % alginate/ß-TCP bioink characteristic for fabricating 3D acellular bioprinted scaffolds was the best approach. 10 % alginate/ß-TCP bioink 3D-printed scaffold exhibited superior physical properties and promoted enhanced cell viability and alkaline phosphatase activity, showing great potential for personalized bone regeneration treatments.

2.
Anal Sci ; 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38483788

RESUMEN

In this paper, we optimized a method for fast and accurate determination of five impurity elements (As, Sb, Bi, Se, and Ge) in graphite samples to overcome the shortcomings of existing methods, such as complicated equipment, cumbersome process, multiple-time preparation, separate determination, and large error in results. Graphite samples were digested with HNO3-H2SO4-HClO4-HF in a high-temperature and high-pressure microwave digestion apparatus, and the elements were extracted and determined separately by AFS (atomic fluorescence spectrometry). There is no element loss during the processing and analysis of this method. The spike recoveries (As: 90.30%-102.3%, Sb: 90.73%-110.0%, Bi: 90.00%-99.67%, Se: 93.33%-110.0%, Ge: 92.26%-104.2%) and precision (RSD%; As: 1.34%-8.96%, Sb: 2.67%-7.10%, Bi: 1.83%-4.58%, Se: 0.36%-3.25%, Ge: 4.41%-8.65%) meet the requirements of the corresponding quality specifications. The method has some advantages (such as no elemental loss, fast testing, strong element targeting, and accurate results), and thus can achieve batch determination of graphite samples. The optimized method for graphite sample and final solution preparations can be used for diverse spectrometric technologies, and that for spectrometer conditions have reference value for HG-AFS instruments.

3.
Nat Med ; 30(4): 1035-1043, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38438735

RESUMEN

Epigenetic modifications of chromatin, including histone acetylation, and tumor angiogenesis play pivotal roles in creating an immunosuppressive tumor microenvironment. In the randomized phase 2 CAPability-01 trial, we investigated the potential efficacy of combining the programmed cell death protein-1 (PD-1) monoclonal antibody sintilimab with the histone deacetylase inhibitor (HDACi) chidamide with or without the anti-vascular endothelial growth factor (VEGF) monoclonal antibody bevacizumab in patients with unresectable chemotherapy-refractory locally advanced or metastatic microsatellite stable/proficient mismatch repair (MSS/pMMR) colorectal cancer. Forty-eight patients were randomly assigned to either the doublet arm (sintilimab and chidamide, n = 23) or the triplet arm (sintilimab, chidamide and bevacizumab, n = 25). The primary endpoint of progression-free survival (PFS) rate at 18 weeks (18wPFS rate) was met with a rate of 43.8% (21 of 48) for the entire study population. Secondary endpoint results include a median PFS of 3.7 months, an overall response rate of 29.2% (14 of 48), a disease control rate of 56.3% (27 of 48) and a median duration of response of 12.0 months. The secondary endpoint of median overall survival time was not mature. The triplet arm exhibited significantly improved outcomes compared to the doublet arm, with a greater 18wPFS rate (64.0% versus 21.7%, P = 0.003), higher overall response rate (44.0% versus 13.0%, P = 0.027) and longer median PFS rate (7.3 months versus 1.5 months, P = 0.006). The most common treatment-emergent adverse events observed in both the triplet and doublet arms included proteinuria, thrombocytopenia, neutropenia, anemia, leukopenia and diarrhea. There were two treatment-related fatalities (hepatic failure and pneumonitis). Analysis of bulk RNA sequencing data from the patients suggested that the triplet combination enhanced CD8+ T cell infiltration, resulting in a more immunologically active tumor microenvironment. Our study suggests that the combination of a PD-1 antibody, an HDACi, and a VEGF antibody could be a promising treatment regimen for patients with MSS/pMMR advanced colorectal cancer. ClinicalTrials.gov registration: NCT04724239 .


Asunto(s)
Aminopiridinas , Benzamidas , Neoplasias Colorrectales , Inhibidores de Histona Desacetilasas , Humanos , Anticuerpos Monoclonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bevacizumab/efectos adversos , Bevacizumab/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Inhibidores de Histona Desacetilasas/efectos adversos , Inhibidores de Histona Desacetilasas/uso terapéutico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/metabolismo , Microambiente Tumoral , Factor A de Crecimiento Endotelial Vascular
4.
Skin Res Technol ; 30(1): e13571, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38196164

RESUMEN

BACKGROUND: Nuclear pleomorphism and tumor microenvironment (TME) play a critical role in cancer development and progression. Identifying most predictive nuclei and TME features of basal cell carcinoma (BCC) may provide insights into which characteristics pathologists can use to distinguish and stratify this entity. OBJECTIVES: To develop an automated workflow based on nuclei and TME features from basaloid cell tumor regions to differentiate BCC from trichoepithelioma (TE) and stratify BCC into high-risk (HR) and low-risk (LR) subtypes, and to identify the nuclear and TME characteristics profile of different basaloid cell tumors. METHODS: The deep learning systems were trained on 161 H&E -stained sections which contained 51 sections of HR-BCC, 50 sections of LR-BCC and 60 sections of TE from one institution (D1), and externally and independently validated on D2 (46 sections) and D3 (76 sections), from 2015 to 2022. 60%, 20% and 20% of D1 data were randomly splitted for training, validation and testing, respectively. The framework comprised four stages: tumor regions identification by multi-head self-attention (MSA) U-Net, nuclei segmentation by HoVer-Net, quantitative feature by handcrafted extraction, and differentiation and risk stratification classifier construction. Pixel accuracy, precision, recall, dice score, intersection over union (IoU) and area under the curve (AUC) were used to evaluate the performance of tumor segmentation model and classifiers. RESULTS: MSA-U-Net model detected tumor regions with 0.910 precision, 0.869 recall, 0.889 dice score and 0.800 IoU. The differentiation classifier achieved 0.977 ± 0.0159, 0.955 ± 0.0181, 0.885 ± 0.0237 AUC in D1, D2 and D3, respectively. The most discriminative features between BCC and TE contained Homogeneity, Elongation, T-T_meanEdgeLength, T-T_Nsubgraph, S-T_HarmonicCentrality, S-S_Degrees. The risk stratification model can well predict HR-BCC and LR-BCC with 0.920 ± 0.0579, 0.839 ± 0.0176, 0.825 ± 0.0153 AUC in D1, D2 and D3, respectively. The most discriminative features between HR-BCC and LR-BCC comprised IntensityMin, Solidity, T-T_minEdgeLength, T-T_Coreness, T-T_Degrees, T-T_Betweenness, S-T_Degrees. CONCLUSIONS: This framework hold potential for future use as a second opinion helping inform diagnosis of BCC, and identify nuclei and TME features related with malignancy and tumor risk stratification.


Asunto(s)
Carcinoma Basocelular , Aprendizaje Profundo , Neoplasias Cutáneas , Humanos , Microambiente Tumoral , Carcinoma Basocelular/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Medición de Riesgo
5.
Int J Ophthalmol ; 17(1): 66-72, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38239937

RESUMEN

AIM: To evaluate the effect of lens surgery on health-related quality of life (HRQoL) of preschool children with congenital ectopia lentis (CEL). METHODS: A prospective self-controlled study was conducted in Zhongshan Ophthalmic Center. Children aged from 5 to 7y whom were diagnosed with CEL and underwent phacoemulsification with scleral-fixated posterior chamber intraocular lens implantation and their parents were enrolled in this study. All of them completed the child and proxy (parental) PedsQL™ 4.0 before and after the surgery. Their preoperative scores were compared to their postoperative ones. Subgroup analyses were performed based on gender and preoperative bilateral presenting visual acuity of the children. RESULTS: Thirty-two children with CEL successfully underwent surgery without any complications, among whom 8 had monocular surgery and 24 had binocular surgery. Preoperative and postoperative questionnaires were completed by 32 child-parent pairs. Surgical intervention could significantly improve the vision of affected children (P<0.001). The medians of physical, psychosocial and total health scores self-reported by the children were 68.75 (62.50, 81.25), 65.00 (60.00, 80.00) and 67.39 (60.87, 78.26) preoperatively and were 93.75 (87.50, 100.00), 90.00 (83.33, 96.67) and 89.13 (85.32, 95.65) postoperatively. The preoperative scores of the affected children were significantly lower in all scales than age-matched healthy children (P<0.001). All the postoperative scores were significantly higher than the preoperative scores in affected children and their parents (P<0.001). In the physical functioning evaluation, the preoperative score reported by parents of girls was higher than parents of boys (P=0.041), and the postoperative score of girls was higher than that of boys (P=0.036). CONCLUSION: CEL is associated with significantly worse quality of life in preschool children. Surgical intervention can significantly improve the HRQoL in affected children from both personal and family perspective.

6.
Cancer Commun (Lond) ; 44(1): 127-172, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38160327

RESUMEN

The 2023 update of the Chinese Society of Clinical Oncology (CSCO) Clinical Guidelines for Gastric Cancer focuses on standardizing cancer diagnosis and treatment in China, reflecting the latest advancements in evidence-based medicine, healthcare resource availability, and precision medicine. These updates address the differences in epidemiological characteristics, clinicopathological features, tumor biology, treatment patterns, and drug selections between Eastern and Western gastric cancer patients. Key revisions include a structured template for imaging diagnosis reports, updated standards for molecular marker testing in pathological diagnosis, and an elevated recommendation for neoadjuvant chemotherapy in stage III gastric cancer. For advanced metastatic gastric cancer, the guidelines introduce new recommendations for immunotherapy, anti-angiogenic therapy and targeted drugs, along with updated management strategies for human epidermal growth factor receptor 2 (HER2)-positive and deficient DNA mismatch repair (dMMR)/microsatellite instability-high (MSI-H) patients. Additionally, the guidelines offer detailed screening recommendations for hereditary gastric cancer and an appendix listing drug treatment regimens for various stages of gastric cancer. The 2023 CSCO Clinical Guidelines for Gastric Cancer updates are based on both Chinese and international clinical research and expert consensus to enhance their applicability and relevance in clinical practice, particularly in the heterogeneous healthcare landscape of China, while maintaining a commitment to scientific rigor, impartiality, and timely revisions.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Oncología Médica , Inmunoterapia , Terapia Neoadyuvante , China
7.
Ying Yong Sheng Tai Xue Bao ; 34(9): 2398-2404, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37899105

RESUMEN

The use of artificial cyanobacteria crusts is one of the effective methods to prevention and control of desertification. Soil fine substance is one of the important factors limiting the colonization and growth of artificial cyanobacteria crusts. We compared the growth of artificial cyanobacterial crusts with different fine substance contents by setting the volume ratios of fine substance to quicksand as 0:1, 1:1, 2:1, 4:1 and 1:0. The results showed that the cover of artificial cyanobacteria crusts increased gradually with the increases of fine substance contents, while the contents of chlorophyll a and extracellular polysaccharide firstly increased and then decreased slightly. The optimum growth of artificial cyanobacterial crusts was achieved under the treatment of 4:1 ratio. Under such treatment after 60 days of incubation, artificial cyanobacteria crusts cover was 70%, and the contents of chlorophyll a, loosely bound exopolysaccharide (LB-EPS), tightly bound exopolysaccharide (TB-EPS), and glycocalyx exopolysaccharide (G-EPS) were 17.5, 70.0, 175.0, and 200.0 µg·cm-2, respectively. Increasing the amount of cyanobacteria under the condition of low fine substance content could promote the formation and growth of artificial cyanobacterial crusts (0.5 g of cyanobacteria per petri dish was the optimal). It could provide a new idea for the large-scale culture of artificial cyanobacterial crusts inoculum.


Asunto(s)
Cianobacterias , Suelo , Clorofila A/metabolismo , Suelo/química , Microbiología del Suelo
8.
Materials (Basel) ; 16(18)2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37763370

RESUMEN

Cu additions notably strengthen Al-Mg-Si and Al-Si-Mg alloys due to the dense precipitation of quaternary nano precipitates during ageing. However, the chemical evolution and mechanical behaviors of the quaternary micro-scale Q constituent phase occurring in cast and homogenized states have rarely been studied. Meanwhile, there exists a type of AlCuMgSi cluster in the cast state, which has been regarded as Q particles. The accurate identification of phase constituents is the basis for the future design of alloys with better performance. In our work, this type of cluster was revealed to consist of α-Al, θ-Al2Cu, Q, and Si phases through micro-to-atomic scale studies using scanning and transmission electron microscopes. The skeleton of the dendrite was θ phase. The second phases in the dendritic eutectic cluster dissolved quickly during a 4 h homogenization at 550 °C. The Q phase was found to effectively absorb the Fe impurities during casting and homogenization. As a result, the formation of other harmful Fe-rich intermetallics was suppressed. These Q constituent particles were observed to break into separate pieces in an intermediately brittle manner when compressed in situ in a scanning electron microscope. These findings provide insights into the thermodynamic modeling of the Al-Mg-Si-Cu system and alloy design.

9.
Materials (Basel) ; 16(16)2023 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-37629898

RESUMEN

Precipitate free zones (PFZs) near grain boundaries generally soften alloys. The quenching rate after solution treatment is an important factor influencing the width of PFZs in Al-Mg-Si-Cu alloy. This study explored the effects of high quenching rates on the grain boundary microstructures and mechanical properties of an Al-Mg-Si-Cu alloy. Samples of various thickness were quenched in water at room temperature and in ethylene glycol at -40 °C, respectively. The results showed that the rapidly quenched samples at -40 °C exhibited better comprehensive mechanical properties than the water-quenched samples. Transmission electron microscopy studies revealed the rapidly quenched samples had wider PFZs, shorter intragranular precipitates, and larger grain boundary precipitates (GBPs) than water-quenched samples. It is proposed that when the quenching rate exceeds the critical cooling rate, e.g., in water quenching or rapid quenching, the formation of PFZs is controlled by the solute depletion mechanism rather than the vacancy depletion mechanism. The nucleation and growth of GBPs thus lead to the depletion of solute atoms, resulting in wider PFZs rather than thinner PFZs according to previous knowledge. This research provides valuable insights into the application of rapid quenching technology for modifying alloys' microstructures and properties.

10.
Zhongguo Zhong Yao Za Zhi ; 48(8): 2116-2125, 2023 Apr.
Artículo en Chino | MEDLINE | ID: mdl-37282900

RESUMEN

This study aims to separate and characterize self-assembled nanoparticles(SAN) from Shaoyao Gancao Decoction(SGD) and determine the content of active compounds. Further, we aimed to observe the therapeutic effect of SGD-SAN on imiquimod-induced psoriasis in mice. The separation of SGD was performed by dialysis, and the separation process was optimized by single factor experiment. The SGD-SAN isolated under the optimal process was characterized, and the content of gallic acid, albiflorin, paeoniflorin, liquiritin, isoliquiritin apioside, isoliquiritin, and glycyrrhizic acid in each part of SGD was determined by HPLC. In the animal experiment, mice were assigned into a normal group, a model group, a methotrexate group(0.001 g·kg~(-1)), and SGD, SGD sediment, SGD dialysate, and SGD-SAN groups of different doses(1, 2, and 4 g·kg~(-1)) respectively. The psoriasis grade of mice was evaluated based on the pathological changes of skin lesions, the content of inflammatory cytokines, organ index and other indicators. The results showed that SAN obtained by centrifugation at 13 000 r·min~(-1) for 30 min was stable after dialysis for 4 times, which were uniform spherical nanoparticles with the particle size of(164.43±1.34) nm, the polydispersity index of(0.28±0.05), and the Zeta potential of(-12.35±0.80) mV. The active compound content accounted for more than 70% of SGD. Compared with the model group, SAN and SGD decreased the skin lesion score, spleen index, and inflammatory cytokine levels(P<0.05 or P<0.01) and alleviated the skin thickening and infiltration of inflammatory cells. However, the sediment group and the dialysate group had no obvious effect. SGD showed a good therapeutic effect on imiquimod-induced psoriasis in mice, and SAN demonstrated the effect equivalent to SGD in a dose-dependent manner. Therefore, we conclude that the SAN formed during decocting is the main active form of SGD, which can lower the levels of inflammatory cytokines, promote the normal differentiation of keratinocytes, and reduce the infiltration of inflammatory cells in the treatment of psoriasis lesions in mice.


Asunto(s)
Medicamentos Herbarios Chinos , Ratones , Animales , Imiquimod , Medicamentos Herbarios Chinos/farmacología , Ácido Glicirrínico , Cromatografía Líquida de Alta Presión/métodos
11.
Sci Rep ; 13(1): 9629, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37316546

RESUMEN

Underwater crack repair is challenging due to drainage and exhaust, slurry retention at fixed points, and other issues. Magnetically driven epoxy resin cement slurry was developed, which can perform directional movement and fixed-point retention of slurry under the effect of an applied magnetic field. This paper focuses on slurry fluidity and tensile properties. Firstly, in the preliminary pre-study, the main influencing factors of the ratios were determined. Then, the optimum range of each factor is determined by a single-factor experiment. Furthermore, the response surface method (RSM) is applied to obtain an optimal ratio. Finally, the slurry is characterized by micro. Results showed that the evaluation index F proposed in this paper can well evaluate the interaction between fluidity (X) and tensile strength (Y). The 2FI regression model and the quadratic regression model are developed with fluidity and tensile strength as the response values and Epoxy Resin (ER) content, water-cement ratio, Fe3O4 content and sulphoaluminate cement (SAC) content as the influencing factors, and have reasonable fit and reliability. The relationship between the degree of influence of the influencing factors on the response value X and the response value Y in ascending order was: ER content > water-cement ratio > SAC content > Fe3O4 content. The magnetically driven slurry made by the optimal ratio can reach a fluidity rate of 223.31 mm and a tensile strength of 2.47 MPa. This is with relative errors of 0.36% and 1.65% from the model predicted values. Microscopic analysis showed that the magnetically driven epoxy resin cement slurry had a favorable crystalline phase, surface morphology, and structural composition.

12.
Behav Sci (Basel) ; 13(6)2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37366746

RESUMEN

In the volatile, uncertain, complex, and ambiguous environment (VUCA), employees can better match the organization and jobs by crafting their job perceptions, work tasks, and relationships, which is valuable to maintain organizational sustainable competitiveness and promote employees' personal growth. This study explores the influence mechanisms of job autonomy and work meaning on employees' job-crafting behaviors and the moderating effect of perceived organizational change through a survey of 318 employees in Chinese companies. The results show that job autonomy and work meaning can promote employees' job-crafting behaviors by increasing individuals' harmonious work passion. The indirect effects of job autonomy and work meaning on employee job-crafting behaviors through harmonious work passion are stronger for individuals with high perceived organizational change relative to those with low perceived organizational change. Organizations should concentrate on job redesign to improve employees' job autonomy and work meaning. A climate of change should also be created within the organization to keep employees aware of the crisis. Meanwhile, employees should actively use work resources to meet the changing needs of organizational development and promote individual career development through job-crafting behaviors.

13.
Molecules ; 28(9)2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37175301

RESUMEN

Transition-metal-doped boron nanoclusters exhibit unique structures and bonding in chemistry. Using the experimentally observed seashell-like borospherenes C2 B28-/0 and Cs B29- as ligands and based on extensive first-principles theory calculations, we predict herein a series of novel transition-metal-centered endohedral seashell-like metallo-borospherenes C2 Sc@B28- (1), C2 Ti@B28 (2), C2 V@B28+ (3), and Cs V@B292- (4) which, as the global minima of the complex systems, turn out to be the boron analogues of dibenzenechromium D6h Cr(C6H6)2 with two B12 ligands on the top and bottom interconnected by four or five corner boron atoms on the waist and one transition-metal "pearl" sandwiched at the center in between. Detailed molecular orbital, adaptive natural density partitioning (AdNDP), and iso-chemical shielding surface (ICSS) analyses indicate that, similar to Cr(C6H6)2, these endohedral seashell-like complexes follow the 18-electron rule in bonding patterns (1S21P61D10), rendering spherical aromaticity and extra stability to the systems.

14.
Chemphyschem ; 24(9): e202300222, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37129295

RESUMEN

The front cover artwork is provided by Prof. Si-Dian Li's group at Shanxi University, China. The image shows the smallest perfect core-shell octahedral borospherene Oh B@B38 + and its endohedral metallo-borospherene analogs Oh Be@B38 and Oh Zn@B38 obtained at first-principles theory. Read the full text of the Research Article at 10.1002/cphc.202200947.

15.
Foods ; 12(7)2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37048202

RESUMEN

Functional oligosaccharides exert obesity-reducing effects by acting at various pathological sites responsible for the development of obesity. In this study, tamarind xyloglucan oligosaccharides (TXOS) were used to attenuate metabolic disorders via the gut-liver axis in mice with high-fat-diet (HFD)-induced obesity, as determined through LC/MS-MS and 16S rRNA sequencing technology. A TXOS dose equivalent to 0.39 g/kg/day in humans restored the gut microbiota in obese mice, which was in part supported by the key microflora, particularly Bifidobacterium pseudolongum. Moreover, TXOS reduced the abundance of opportunistic pathogen species, such as Klebsiella variicola and Romboutsia ilealis. The bodyweight and weight gain of TXOS-treated (4.8 g/kg per day) mice began to decrease at the 14th week, decreasing by 12.8% and 23.3%, respectively. Sixteen fatty acids were identified as potential biomarkers in the liver, and B. pseudolongum and caprylic acid were found to tightly regulate each other. This was associated with reduced inflammation in the liver, circulation, and adipose tissue and protection from metabolic disorders. The findings of this study indicate that TXOS can significantly increase the gut microbiota diversity of obese mice and restore the HFD-induced dysbiosis of gut microbiota.

16.
Appl Microbiol Biotechnol ; 107(11): 3579-3591, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37115252

RESUMEN

2'-Fucosyllactose (2'-FL) is known for its ability to provide various health benefits to infants, such as gut maturation, pathogen resistance, improved immunity, and nervous system development. However, the production of 2'-FL using α-L-fucosidases is hindered by the lack of low-cost natural fucosyl donors and high-efficiency α-L-fucosidases. In this work, a recombinant xyloglucanase from Rhizomucor miehei (RmXEG12A) was applied to produce xyloglucan-oligosaccharide (XyG-oligos) from apple pomace. Then, an α-L-fucosidase gene (PbFucB) was screened from the genomic DNA of Pedobacter sp. CAU209 and expressed in Escherichia coli. The capability of purified PbFucB to catalyze XyG-oligos and lactose to synthesize 2'-FL was further evaluated. The deduced amino acid sequence of PbFucB shared the highest identity (38.4%) with that of other reported α-L-fucosidases. PbFucB showed the highest activity at pH 5.5 and 35 °C. It catalyzed the hydrolysis of 4-nitrophenyl-α-L-fucopyranoside (pNP-Fuc, 20.3 U mg-1), 2'-FL (8.06 U mg-1), and XyG-oligos (0.43 U mg-1). Furthermore, PbFucB demonstrated a high enzymatic conversion rate in 2'-FL synthesis with pNP-Fuc or apple pomace-derived XyG-oligos as donors and lactose as acceptor. Under the optimized conditions, PbFucB converted 50% of pNP-Fuc or 31% of the L-fucosyl residue in XyG-oligos into 2'-FL. This work elucidated an α-L-fucosidase that mediates the fucosylation of lactose and provided an efficient enzymatic strategy to synthesize 2'-FL either from artificial pNP-Fuc or natural apple pomace-derived XyG-oligos. KEY POINTS: • Xyloglucan-oligosaccharide (XyG-oligos) was produced from apple pomace by a xyloglucanase from Rhizomucor miehei. • An α-L-fucosidase (PbFucB) from Pedobacter sp. CAU209 shared the highest identity (38.4%) with reported α-L-fucosidases. •PbFucB synthesized 2'-FL using apple pomace-derived XyG-oligos and lactose with a conversion ratio of 31%.


Asunto(s)
Malus , Pedobacter , Lactante , Humanos , alfa-L-Fucosidasa/genética , alfa-L-Fucosidasa/metabolismo , Malus/metabolismo , Lactosa/metabolismo , Oligosacáridos/metabolismo
17.
Polymers (Basel) ; 15(6)2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36987176

RESUMEN

Manufacturing three-dimensional (3D) objects with polymers/bioceramic composite materials has been investigated in recent years. In this study, we manufactured and evaluated solvent-free polycaprolactone (PCL) and beta-tricalcium phosphate (ß-TCP) composite fiber as a scaffold material for 3D printing. To investigate the optimal ratio of feedstock material for 3D printing, the physical and biological characteristics of four different ratios of ß-TCP compounds mixed with PCL were investigated. PCL/ß-TCP ratios of 0 wt.%, 10 wt.%, 20 wt.%, and 30 wt.% were fabricated, with PCL melted at 65 °C and blended with ß-TCP with no solvent added during the fabrication process. Electron microscopy revealed an even distribution of ß-TCP in the PCL fibers, while Fourier transform infrared spectroscopy demonstrated that the biomaterial compounds remained intact after the heating and manufacturing process. In addition, adding 20% ß-TCP into the PCL/ß-TCP mixture significantly increased hardness and Young's Modulus by 10% and 26.5%, respectively, suggesting that PCL-20 has better resistance to deformation under load. Cell viability, alkaline phosphatase (ALPase) activity, osteogenic gene expression, and mineralization were also observed to increase according to the amount of ß-TCP added. Cell viability and ALPase activity were 20% higher with PCL-30, while upregulation for osteoblast-related gene expression was better with PCL-20. In conclusion, PCL-20 and PCL-30 fibers fabricated without solvent exhibited excellent mechanical properties, high biocompatibility, and high osteogenic ability, making them promising materials for 3D printing customized bone scaffolds promptly, sustainably, and cost-effectively.

18.
Ying Yong Sheng Tai Xue Bao ; 34(1): 11-17, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36799371

RESUMEN

Global climate change will increase surface soil temperature, with consequences on plant seedling growth and population dynamics. In this study, we carried out a field experiment to investigate the effects of 2 ℃ soil warming on the growth and physiological characteristics of 1- and 2-year-old seedlings of a dominant tree species in broadleaved Korean pine forest, Juglans mandshurica. The results showed that soil warming significantly increased basal diameter, root length, total leaf area, leaf dry weight, root dry weight, total biomass, apparent photosynthetic electron transfer rate (ETR), PSⅡ actual photochemical efficiency (ΦPSⅡ), and apparent photosynthetic electrophotochemical quenching coefficient (qP) of 1-year-old seedlings by 18.3%, 66.7%, 94.4%, 105.9%, 95.8%, 37.8%, 89.5%, 100.0%, and 71.4%, respectively. Soil warming significantly increased basal diameter, total leaf area, leaf dry weight, total biomass, leaf superoxide dismutase activity, peroxidase activity, catalase activity and free proline content, ETR, ΦPSⅡ, and qP of 2-year-old seedlings by 12.5%, 180.5%, 97.3%, 42.5%, 23.9%, 20.4%, 14.9%, 20.7%, 66.7%, 283.3% and 284.6%, respectively. There was an interaction between seedling age and soil warming on the root-shoot ratio and the ΦPSⅡ and qP in chlorophyll fluorescence parameters, in that soil warming significantly reduced the root-shoot ratio of 2-year-old seedlings and that the increase of chlorophyll fluorescence parameters of 2-year-old seedlings (4.1-4.6 times) was much higher than that of 1-year-old seedlings (1.5-1.8 times). Soil warming of 2 ℃ was beneficial to the growth of 1- and 2-year-old J. mandshurica seedlings and increased their regeneration potential. In particular, 2-year-old J. mandshurica seedlings responded to soil warming by increasing leaf area, improving leaf photochemical efficiency, and enhancing protective enzyme activity to increase resistance.


Asunto(s)
Juglans , Plantones , Clorofila , Fotosíntesis , Hojas de la Planta , Suelo
19.
Chemphyschem ; 24(9): e202200947, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-36715013

RESUMEN

Planar, tubular, cage-like, and bilayer boron clusters Bn +/0/- (n=3∼48) have been observed in joint experimental and theoretical investigations in the past two decades. Based on extensive global searches augmented with first-principles theory calculations, we predict herein the smallest perfect core-shell octahedral borospherene Oh B@B38 + (1) and its endohedral metallo-borospherene analogs Oh Be@B38 (2), and Oh Zn@B38 (3) which, with an octa-coordinate B, Be or Zn atom located exactly at the center, turn out to be the well-defined global minima of the systems highly stable both thermodynamically and dynamically. B@B38 + (1) represents the first boron-containing molecule reported to date which contains an octa-coordinate B center covalently coordinated by eight face-capping boron atoms at the corners of a perfect cube in the first coordination sphere. Detailed natural bonding orbital (NBO) and adaptive natural density partitioning (AdNDP) bonding analyses indicate that these high-symmetry core-shell complexes X@B38 +/0/- (X=B, Be, Zn) as super-noble gas atoms follow the octet rule in coordination bonding patterns (1S2 1P6 ), with one delocalized 9c-2e S-type coordination bond and three delocalized 39c-2e P-type coordination bonds formed between the octa-coordinate X center and its octahedral Oh B38 ligand to effectively stabilize the systems. Their IR, Raman, and UV-Vis spectra are computationally simulated to facilitate their spectroscopic characterizations.

20.
Kaohsiung J Med Sci ; 39(1): 87-94, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36354204

RESUMEN

Clinical, laboratory, and microbiological features, clinical outcomes, and pyogenic liver abscess (PLA) prognosis evaluation in non-liver cancer (Non-LC) and liver cancer patients treated with transarterial chemoembolization (TACE, LC-TACE). Clinical data of 48 consecutive PLA patients from January 2016 to December 2020 were retrospectively analyzed. Mortality between two PLA patient groups were compared, and mortality risk factors were evaluated. A total of 48 PLA patients (31 males and 17 females) from January 2016 to December 2020 met the study's inclusion criteria. There were 32 and 16 patients in the Non-LC and LC-TACE groups, respectively. Positive pus culture rate in the Non-LC group was 87.5% and positive pus culture rate in LC-TACE group was 81.3%. In the Non-LC group, 28 patients improved after treatment, 1 patient did not improve, and 3 patients died during hospitalization, with a 9.4% mortality rate. In the LC-TACE group, nine patients improved after treatment, three patients did not improve, and four patients died during hospitalization, with a 25% mortality rate. The Non-LC group cure time was 37.4 ± 23.1 days, while the LC-TACE group was 91.5 ± 49.7 days. PLA of the Non-LC group and the LC-TACE group were different in terms of pathogenic bacteria and cure time, and so on. A more comprehensive treatment should be considered for PLA after TACE.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Absceso Piógeno Hepático , Neoplasias Hepáticas , Masculino , Femenino , Humanos , Absceso Piógeno Hepático/terapia , Absceso Piógeno Hepático/microbiología , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/etiología , Estudios Retrospectivos , Neoplasias Hepáticas/patología , Quimioembolización Terapéutica/efectos adversos , Resultado del Tratamiento
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