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1.
Nature ; 590(7844): 47-56, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33536649

RESUMEN

Cellulose is the most abundant biopolymer on Earth, found in trees, waste from agricultural crops and other biomass. The fibres that comprise cellulose can be broken down into building blocks, known as fibrillated cellulose, of varying, controllable dimensions that extend to the nanoscale. Fibrillated cellulose is harvested from renewable resources, so its sustainability potential combined with its other functional properties (mechanical, optical, thermal and fluidic, for example) gives this nanomaterial unique technological appeal. Here we explore the use of fibrillated cellulose in the fabrication of materials ranging from composites and macrofibres, to thin films, porous membranes and gels. We discuss research directions for the practical exploitation of these structures and the remaining challenges to overcome before fibrillated cellulose materials can reach their full potential. Finally, we highlight some key issues towards successful manufacturing scale-up of this family of materials.


Asunto(s)
Biotecnología/métodos , Biotecnología/tendencias , Celulosa/química , Nanoestructuras/química , Desarrollo Sostenible/tendencias , Materiales Biocompatibles/química , Geles/química , Humanos , Porosidad
2.
Chem Rev ; 123(5): 1843-1888, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36260771

RESUMEN

The building sector, including building operations and materials, was responsible for the emission of ∼11.9 gigatons of global energy-related CO2 in 2020, accounting for 37% of the total CO2 emissions, the largest share among different sectors. Lowering the carbon footprint of buildings requires the development of carbon-storage materials as well as novel designs that could enable multifunctional components to achieve widespread applications. Wood is one of the most abundant biomaterials on Earth and has been used for construction historically. Recent research breakthroughs on advanced engineered wood products epitomize this material's tremendous yet largely untapped potential for addressing global sustainability challenges. In this review, we explore recent developments in chemically modified wood that will produce a new generation of engineered wood products for building applications. Traditionally, engineered wood products have primarily had a structural purpose, but this review broadens the classification to encompass more aspects of building performance. We begin by providing multiscale design principles of wood products from a computational point of view, followed by discussion of the chemical modifications and structural engineering methods used to modify wood in terms of its mechanical, thermal, optical, and energy-related performance. Additionally, we explore life cycle assessment and techno-economic analysis tools for guiding future research toward environmentally friendly and economically feasible directions for engineered wood products. Finally, this review highlights the current challenges and perspectives on future directions in this research field. By leveraging these new wood-based technologies and analysis tools for the fabrication of carbon-storage materials, it is possible to design sustainable and carbon-negative buildings, which could have a significant impact on mitigating climate change.

3.
Biomacromolecules ; 25(4): 2509-2519, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38514378

RESUMEN

This study conducted a detailed evaluation of the feasibility of producing cellulose microfibrils (CMF) from a kraft-bleached hardwood pulp at high solid contents with and without pretreatments. CMFs produced by planetary ball milling at solid contents 17 and 28% were compared with those from 1 to 5% under the same milling conditions. Fiber pretreatments using a commercial endoglucanase and mechanical refining using a laboratory PFI mill were also applied before ball milling at a solid content of 28%. Two mechanisms of fiber fibrillation were identified from the results obtained: (i) ball and fiber/fibril interactions─the primary mechanism and (ii) interfiber/fibril frictional and tensional interactions─the secondary mechanism. The secondary mechanism plays an important role only in early-stage fibrillation and became less important as fibrillation proceeded in the later stage toward nanofibrillation. Improving fiber dispersion at lower solid content facilitated fibrillation. Endoglucanase pretreatment substantially shortened fibers to result in a "pulverized-like" CMF with short fibrils at an extended milling time. Mechanical refining of fibers facilitated fibrillation to result in CMFs with a morphology similar to that from runs without any fiber pretreatment but for a much shorter milling time. Both CMF water retention value (WRV) measurements and CMF suspension sedimentation experiments showed results consistent with imaging observations. The insights gained through this study provide relevant information with commercial significance regarding CMF production at high solids, which is not currently available in the literature.


Asunto(s)
Celulasa , Microfibrillas , Carbohidratos , Celulosa
4.
Nature ; 554(7691): 224-228, 2018 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-29420466

RESUMEN

Synthetic structural materials with exceptional mechanical performance suffer from either large weight and adverse environmental impact (for example, steels and alloys) or complex manufacturing processes and thus high cost (for example, polymer-based and biomimetic composites). Natural wood is a low-cost and abundant material and has been used for millennia as a structural material for building and furniture construction. However, the mechanical performance of natural wood (its strength and toughness) is unsatisfactory for many advanced engineering structures and applications. Pre-treatment with steam, heat, ammonia or cold rolling followed by densification has led to the enhanced mechanical performance of natural wood. However, the existing methods result in incomplete densification and lack dimensional stability, particularly in response to humid environments, and wood treated in these ways can expand and weaken. Here we report a simple and effective strategy to transform bulk natural wood directly into a high-performance structural material with a more than tenfold increase in strength, toughness and ballistic resistance and with greater dimensional stability. Our two-step process involves the partial removal of lignin and hemicellulose from the natural wood via a boiling process in an aqueous mixture of NaOH and Na2SO3 followed by hot-pressing, leading to the total collapse of cell walls and the complete densification of the natural wood with highly aligned cellulose nanofibres. This strategy is shown to be universally effective for various species of wood. Our processed wood has a specific strength higher than that of most structural metals and alloys, making it a low-cost, high-performance, lightweight alternative.


Asunto(s)
Madera/química , Aleaciones/química , Pared Celular/química , Celulosa/química , Calor , Lignina/química , Lignina/aislamiento & purificación , Metales/química , Peso Molecular , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Hidróxido de Sodio/química , Sulfitos/química , Resistencia a la Tracción , Madera/clasificación
5.
Nano Lett ; 23(18): 8411-8418, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37677149

RESUMEN

Bamboo composite is an attractive candidate for structural materials in applications such as construction, the automotive industry, and logistics. However, its development has been hindered due to the use of harmful petroleum-derived synthetic adhesives or low-bonding biobased adhesives. Herein, we report a novel bioadhesion strategy based on in situ lignin bonding that can process natural bamboo into a scalable and high-performance composite. In this process, lignin bonds the cellulose fibrils into a strong network via a superstrong adhesive interface formed by hydrogen bonding and nanoscale entanglement. The resulting in situ glued-bamboo (glubam) composite exhibits a record-high shear strength of ∼4.4 MPa and a tensile strength of ∼300 MPa. This in situ lignin adhesion strategy is facile, highly scalable, and cost-effective, suggesting a promising route for fabricating strong and sustainable structural bamboo composites that sequester carbon and reduce our dependence on petrochemical-based adhesives.

6.
Ann Oncol ; 34(2): 163-172, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36400384

RESUMEN

BACKGROUND: Neoadjuvant therapy is recommended for locally advanced esophageal cancer, but the optimal strategy remains unclear. We aimed to evaluate the safety and efficacy of neoadjuvant chemoradiotherapy (nCRT) versus neoadjuvant chemotherapy (nCT) followed by minimally invasive esophagectomy (MIE) for locally advanced esophageal squamous cell carcinoma (ESCC). PATIENTS AND METHODS: Eligible patients staged as cT3-4aN0-1M0 ESCC were randomly assigned (1 : 1) to the nCRT or nCT group stratified by age, cN stage, and centers. The chemotherapy, based on paclitaxel and cisplatin, was administered to both groups, while concurrent radiotherapy was added for the nCRT group; then MIE was carried out. The primary endpoint was 3-year overall survival. This study is registered with ClinicalTrials.gov (NCT03001596). RESULTS: A total of 264 patients were eligible for the intention-to-treat analysis. By 30 November 2021, 121 deaths had occurred. The median follow-up was 43.9 months (interquartile range 36.6-49.3 months). The overall survival in the intention-to-treat population was comparable between the nCRT and nCT strategies [hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.58-1.18; P = 0.28], with a 3-year survival rate of 64.1% (95% CI 56.4% to 72.9%) versus 54.9% (95% CI 47.0% to 64.2%), respectively. There were also no differences in progression-free survival (HR 0.83, 95% CI 0.59-1.16; P = 0.27) and recurrence-free survival (HR 1.07, 95% CI 0.71-1.60; P = 0.75), although the pathological complete response in the nCRT group (31/112, 27.7%) was significantly higher than that in the nCT group (3/104, 2.9%; P < 0.001). Besides, a trend of lower risk of recurrence was observed in the nCRT group (P = 0.063), while the recurrence pattern was similar (P = 0.802). CONCLUSIONS: NCRT followed by MIE was not associated with significantly better overall survival than nCT among patients with cT3-4aN0-1M0 ESCC. The results underscore the pending issue of the best strategy of neoadjuvant therapy for locally advanced bulky ESCC.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/terapia , Terapia Neoadyuvante/métodos , Neoplasias Esofágicas/tratamiento farmacológico , Esofagectomía , Estudios Prospectivos , Quimioradioterapia/métodos , Estudios Retrospectivos
7.
BMC Biol ; 20(1): 104, 2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35550087

RESUMEN

BACKGROUND: Lifelong production of the many types of mature blood cells from less differentiated progenitors is a hierarchically ordered process that spans multiple cell divisions. The nature and timing of the molecular events required to integrate the environmental signals, transcription factor activity, epigenetic modifications, and changes in gene expression involved are thus complex and still poorly understood. To address this gap, we generated comprehensive reference epigenomes of 8 phenotypically defined subsets of normal human cord blood. RESULTS: We describe a striking contraction of H3K27me3 density in differentiated myelo-erythroid cells that resembles a punctate pattern previously ascribed to pluripotent embryonic stem cells. Phenotypically distinct progenitor cell types display a nearly identical repressive H3K27me3 signature characterized by large organized chromatin K27-modification domains that are retained by mature lymphoid cells but lost in terminally differentiated monocytes and erythroblasts. We demonstrate that inhibition of polycomb group members predicted to control large organized chromatin K27-modification domains influences lymphoid and myeloid fate decisions of primary neonatal hematopoietic progenitors in vitro. We further show that a majority of active enhancers appear in early progenitors, a subset of which are DNA hypermethylated and become hypomethylated and induced during terminal differentiation. CONCLUSION: Primitive human hematopoietic cells display a unique repressive H3K27me3 signature that is retained by mature lymphoid cells but is lost in monocytes and erythroblasts. Intervention data implicate that control of this chromatin state change is a requisite part of the process whereby normal human hematopoietic progenitor cells make lymphoid and myeloid fate decisions.


Asunto(s)
Histonas , Células Madre Pluripotentes , Diferenciación Celular , Cromatina/genética , Cromatina/metabolismo , Células Madre Hematopoyéticas/metabolismo , Histonas/genética , Humanos , Recién Nacido , Células Madre Pluripotentes/metabolismo
8.
Artículo en Zh | MEDLINE | ID: mdl-37006144

RESUMEN

Objective: To evaluate the thermal environment of different types of public places and the thermal comfort of employees, so as to provide scientific basis for the establishment of microclimate standards and health supervision requirements. Methods: From June 2019 to December 2021, 50 public places (178 times) of 8 categories in Wuxi were selected, including hotels, swimming pools (gymnasiums), bathing places, shopping malls (supermarkets), barber shops, beauty shops, waiting rooms (bus station) and gyms. In summer and winter, microclimate indicators such as temperature and wind speed were measured in all kinds of places, combined with the work attire and physical activity of employees in the places. Fanger thermal comfort equation and center for the built environment (CBE) thermal comfort calculation tool were used to evaluate the predicted mean vote (PMV), predicted percent dissatisfied (PPD) and standard effective temperature (SET) according to the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 55-2020. The modification effects of seasonal and temperature control conditions on thermal comfort were analyzed. The consistency of GB 37488-2019 "Hygienic Indicators and Limits in Public Places" and ASHRAE 55-2020 evaluation results on thermal environment was compared. Results: The thermal sensation of hotel, barber shop staff and the gym front-desk staff were moderate, while the thermal sensation of swimming place lifeguard, bathing place cleaning staff and gym trainer were slightly warm in summer and winter. Waiting room (bus station) cleaning and working staff, shopping mall staff felt slightly warm in summer and moderate in winter. Service staff in bathing places felt slightly warm in winter, while staff in beauty salons felt slightly cool in winter. The thermal comfort compliance of hotel cleaning staff and shopping mall staff in summer was lower than that in winter (χ(2)=7.01, 7.22, P=0.008, 0.007). The thermal comfort compliance of shopping mall staff in the condition of air conditioning off was higher than that in the condition of air conditioning on (χ(2)=7.01, P=0.008). The SET values of front-desk staff in hotels with different health supervision levels were significantly different (F=3.30, P=0.024). The PPD value and SET value of the front-desk staff, and the PPD value of cleaning staff of hotels above three stars were lower than those of hotels below three stars (P<0.05). The thermal comfort compliance of front-desk staff and cleaning staff in hotels above three stars was higher than that in hotels below three stars (χ(2)=8.33, 8.09, P=0.016, 0.018). The consistency of the two criteria was highest among waiting room (bus station) staff (100.0%, 1/1) and lowest among gym front-desk staff (0%, 0/2) and waiting room (bus station) cleaning staff (0%, 0/1) . Conclusion: There are different degrees of thermal discomfort in different seasons, under the condition of air conditioning and health supervision, and the microclimate indicators can not fully reflect the thermal comfort of human body. The health supervision of microclimate should be strengthened, the applicability of health standard limit value should be evaluated in many aspects, and the thermal comfort of occupational group should be improved.


Asunto(s)
Aire Acondicionado , Frío , Humanos , Temperatura , Viento , Estaciones del Año
9.
Zhonghua Gan Zang Bing Za Zhi ; 30(3): 244-248, 2022 Mar 20.
Artículo en Zh | MEDLINE | ID: mdl-35462478

RESUMEN

Liver is one of the most important organs in the human body. Liver diseases are also a major threat to human health and longevity. Hepatic decompensation treatment is quite difficult due to multiple reasons. Extracorporeal liver support devices are unable to solve this problem, and there is a severe shortage of orthotopic liver transplant donors. Study of pluripotent stem cell-derived hepatocytes and organoids can determine not only hepatocyte fate, but also liver development, regeneration mechanisms, and pathophysiology. Furthermore, it can be used for drug screening in order to provide a stable source of functional hepatocytes for future transplantation therapy. Culture of pluripotent stem cell-derived hepatocytes and organoids has a self-organizing process similar to liver development, i.e., starting with changes in several key factors, and eventually forming functionally complex cells/organs. This paper introduces the main methods and progress of pluripotent stem cell-derived hepatocytes and organoids, with hope to provide clues for future research.


Asunto(s)
Células Madre Pluripotentes Inducidas , Células Madre Pluripotentes , Diferenciación Celular , Hepatocitos , Humanos , Hígado , Organoides
10.
Zhonghua Yi Xue Za Zhi ; 101(28): 2210-2215, 2021 Jul 27.
Artículo en Zh | MEDLINE | ID: mdl-34333933

RESUMEN

Objective: To explore the application value of three-dimensional reconstruction of liver based on computer software in preoperative evaluation of precise hepatectomy for complex primary liver cancer. Methods: The clinical data of patients in Peking University People's Hospital Hepatobiliary surgery with complicated primary liver cancer from September 17, 2019 to December 20, 2020 were analyzed retrospectively. Preoperative enhanced CT/MR data of patients were collected, and 3D reconstruction of liver was performed in IQQA􀳏-3D Liver system. The liver volume of patients was calculated, the size and location of tumor were described, and the relationship between tumor and intrahepatic bile duct, portal vein, hepatic artery and inferior vena cava was described. Preoperative decision-making and treatment plan were made to compare the compliance of the actual operation plan with the planned operation plan under the guidance of three-dimensional reconstruction. Results: Among all 10 patients, there were 6 males and 4 females, aged 36 to 75 years. There were 6 cases of Child-Pugh grade A and 4 cases of B liver function. There were 5 cases of portal vein variation and 5 cases of hepatic artery variation. The range and M(Q1,Q3)of actual liver volume measured by 3D reconstruction in 10 patients was 895- 2 477 cm3 and [1 444(1 001, 1 854)] cm3;the nodule volume was 7-1 808 [133(50, 566)] cm3;the nodule volume in the liver was 0.8%-73.0% [11.0(3.3,32.7)]% and the number of suspected lesions was 1-7. In the end, 6 patients received surgical treatment;3 received chemotherapy, and 1 received conservative treatment. The preoperative three-dimensional reconstruction of liver anatomy and tumor location of the patients receiving surgical treatment were basically consistent with the intraoperative situation. There was no case of liver failure or death during perioperative period. Conclusion: In the preoperative evaluation of precise hepatectomy for complex primary liver cancer, 3D reconstruction can improve the rationality of treatment and the surgeon's understanding of the anatomical characteristics of the liver, so as to select the best treatment for patients, which has great application value.


Asunto(s)
Imagenología Tridimensional , Neoplasias Hepáticas , Femenino , Hepatectomía , Humanos , Neoplasias Hepáticas/cirugía , Masculino , Vena Porta , Estudios Retrospectivos
11.
Zhonghua Wai Ke Za Zhi ; 59(6): 513-519, 2021 Jun 01.
Artículo en Zh | MEDLINE | ID: mdl-34102737

RESUMEN

Objective: To evaluate the safety and effectiveness of a new Chinese-made surgical biopatch for atrial septum under the establishment of atrial septal defect animal model in miniature pigs. Methods: From June 2018 to April 2019, 26 pigs were divided into experimental group (15 pigs) and the control group (11 pigs). Animal models of atrial septal defect were established by traditional surgical methods. The to-be-evaluated and listed surgical biological patches (with a diameter of 10 mm) were implanted in the experimental group and the control group to repair the atrial septal defect. Cardiac ultrasound and blood examination of all animals were performed before and at 7, 30, 90, 180 days after operation, the results were analyzed with repetitive measurement and analysis of variance. At 90 days and 180 days after the operation, tissue samples were taken from animals after euthanasia. Pathological examination of heart and major organs were conducted. The independent sample t test and rank sum test were used to compare the data between the two groups, and the nonparametric was used to compare the patch calcification score between the two groups. Results: In total of 26 animals, 14 animals in the experimental group(6 at 90 days, 8 at 180 days) and 9 animals in the control group(4 at 90 days, 5 at 180 days) reached the end of the experiment. The other 3 animals (1 in the experimental group and 2 in the control group) died of arrhythmia, whole heart failure and right heart failure, the results of pathological examination showed that the causes of death were unrelated to the experimental materials. Cardiac ultrasound showed no patch leakage in all animals. There was no statistically significant difference in cardiac ultrasound and blood examination between the two groups at different time points after operation (all P>0.05). The pathological results showed that all the implants were intact and had good biocompatibility. There was no significant difference in the mean endothelialization rate between the experimental group and the control group at 90 and 180 days after operation ((80.8±29.1)% vs. (82.5±23.6)%, t=0.095, P=0.927; (78.8±36.4)% vs. (82.0±19.2)%, t=0.182, P=0.859) on 90 and 180 days, there was no significant difference in the patch calcification score between the two groups (1.00(1.25) vs. 2.00(0.75), Z=6.500, P=0.214; 0(0.75) vs. 1.00(2.00), Z=12.000, P=0.139). Conclusion: The new Chinese-made surgical biopatch for atrial septum has comparable safety and efficacy to that of the marketable patch in miniature pig atrial septal defect animal model.


Asunto(s)
Tabique Interatrial , Defectos del Tabique Interatrial , Animales , China , Ecocardiografía , Defectos del Tabique Interatrial/cirugía , Prótesis e Implantes , Porcinos
12.
Zhonghua Yi Xue Za Zhi ; 100(32): 2481-2487, 2020 Aug 25.
Artículo en Zh | MEDLINE | ID: mdl-32829592

RESUMEN

Objective: To explore the relationship between family with sequence similarity 13 member A (FAM13A) gene and small airway remodeling in chronic obstructive pulmonary disease (COPD), and the effect of interference with FAM13A gene expression on the apoptosis and proliferation phenotype of human airway epithelial cells (16HBE). Methods: From January 2018 to January 2020, 74 patients in the Department of Thoracic Surgery of General Hospital of Ningxia Medical University were treated by surgery for lung tumors or pulmonary bullae. According to the lung function and smoking history, the 74 patients were divided into four groups: non-smoking group with normal lung function (normal group, 23 patients), smoking group with normal lung function (smoking group, 24 patients), non-smoking group with COPD (11 patients) and smoking group with COPD (16 patients). The expression of FAM13A in small airway of each group was detected by immunohistochemistry, and the correlation between FAM13A and the airflow restriction indexes by pulmonary function was analyzed. The shRNA fragment of FAM13A gene was designed, and the shRNA lentivirus vector of FAM13A gene was constructed and packaged. The expression level of FAM13A gene was detected by real-time fluorescent quantitative PCR (qRT-PCR) and Western blot, and the best shRNA sequence was screened. Flow cytometry was used to detect apoptosis rate and the fluorescence intensity of proliferation marker Ki-67 in 16HBE cells. Results: FAM13A was mainly expressed in the cytoplasm of small airway epithelial cells. The levels of FAM13A absorbance (A) of small airway epithelial cells in non-smoking group and smoking group with COPD were higher than those in normal group and smoking group (0.365±0.026, 0.412±0.053 to 0.113±0.018, 0.105±0.009, all P<0.05), and they were negatively correlated with forced expiratory volume in 1s/forced vital capacity (FEV(1)/FVC) and FEV(1)% pre (r=-0.48 and r=-0.40, all P<0.05). The FAM13A shRNA lentiviral vector was successfully constructed, and FAM13A interference was successfully achieved in the 16HBE cell line. After infection of 16HBE cells, the results of qRT-PCR and Western blot showed that the expression of FAM13A in shRNA-target-2 group decreased (all P<0.01). Compared with the negative control group (shRNA-NC), the apoptosis rate of FAM13A shRNA group decreased (P=0.023), and the fluorescence intensity of Ki-67 also decreased (P=0.042). Conclusions: FAM13A gene expression is increased in COPD small airway epithelial cells, and it is related to COPD airflow limitation. FAM13A gene may participate in the process of COPD remodeling by affecting the apoptosis and proliferation of human airway epithelial cells.


Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias) , Enfermedad Pulmonar Obstructiva Crónica , Apoptosis , Proliferación Celular , Células Epiteliales , Humanos , Pulmón
13.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(11): 1295-1299, 2020 Nov 06.
Artículo en Zh | MEDLINE | ID: mdl-33147932

RESUMEN

To explore the threshold effect of body mass index (BMI) on bone mineral density (BMD) in Chinese women living in the fluorosis area, we conducted a cross-sectional study and recruited 722 women in rural areas in Henan Province, China. After detection and analyses, we found that compared with the normal BMI group, the risk of osteoporosis in the overweight and obese groups were reduced by 32% and 69%, respectively. Threshold effect analysis showed that BMD was positively correlated with BMI when BMI was 16.8-31.2 kg/m2; while when BMI was greater than 31.2 kg/m2, the correlation reached saturation. The correlation observed between low-to-moderate fluoride exposure and BMD in rural women was not significant.


Asunto(s)
Densidad Ósea , Osteoporosis , Absorciometría de Fotón , Índice de Masa Corporal , China/epidemiología , Estudios Transversales , Femenino , Humanos
14.
Zhonghua Yi Xue Za Zhi ; 99(34): 2681-2686, 2019 Sep 10.
Artículo en Zh | MEDLINE | ID: mdl-31505719

RESUMEN

Objective: To investigate the phenomenon of small airway epithelial-mesenchymal transition (EMT) in patients with normal pulmonary function and chronic obstructive pulmonary disease (COPD) who received surgical treatment for lung tumors. Methods: In this study, 52 patients undergoing surgical treatment for lung tumors admitted to the General Hospital of Ningxia Medical University were included from January 2018 to January 2019. According to the preoperative pulmonary function and smoking history, patients were divided into group A (non-smoking with normal pulmonary function group, 15 patients), group B (smoking with normal pulmonary function group, 21 patients), group C (COPD stable phase group, 16 patients). HE staining was performed to observe the pathological changes in small airway and lung tissue. Immunohistochemistry was used to detect the localization and expression of E-cadherin, α-smooth muscle actin (α-SMA) and Vimentin in small airway. Western blot was used to detect the levels of E-cadherin, α-SMA and Vimentin. Results: (1) There were no significant differences in age, gender, and the ratio of disease composition among the three groups (P>0.05), but forced expiratory volume in one second (FEV(1)) as percentage of predicted value (FEV(1)%pred) and FEV(1)/forced vital capacity (FEV(1)/FVC) in group C were lower than those in groups A and B (all P<0.01), while there was no significant difference between group A and group B (P>0.05); (2) the bronchial wall thickness in group B and group C were higher than that of group A [(32.4±2.4) and (54.6±4.9) vs (22.4±2.2) µm], and group C was significantly higher than group B (P=0.003); (3) the expression levels of E-cadherin in the epithelial cells of small airway in group B and group C were lower than those in group A (0.021±0.008 and 0.018±0.007 vs 0.062±0.010) (all P<0.05), while the levels of mesenchymal cell markers such as α-SMA and Vimentin in group B and group C were higher than group A, and group C was higher than group B (α-SMA: 0.641±0.113, 0.780±0.133 vs 0.404±0.123; Vimentin: 0.064±0.033, 0.083±0.022 vs 0.030±0.021) (P=0.002 and P=0.003). Conclusion: In patients undergoing surgical treatment of lung tumors, there is EMT in the small airways of patients with COPD, and EMT has occurred in the small airways of smokers with normal pulmonary function.


Asunto(s)
Neoplasias Pulmonares , Enfermedad Pulmonar Obstructiva Crónica , Transición Epitelial-Mesenquimal , Humanos , Pulmón , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/cirugía , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/cirugía , Pruebas de Función Respiratoria
15.
Zhonghua Yi Xue Za Zhi ; 99(40): 3145-3151, 2019 Oct 29.
Artículo en Zh | MEDLINE | ID: mdl-31694105

RESUMEN

Objective: To analyze the distribution of gene mutations in newly diagnosed acute myeloid leukemia (AML) patients, based on next generation sequencing technology (NGS) and to evaluate their value in AML risk stratification. Methods: The study analyzed 453 newly diagnosed AML(excluded acute promyelocytic leukemia, APL) patients from seven hospitals in Shanghai, from January 1st 2014 to December 31th 2017. RNA and DNA were extracted from pretreatment bone marrow mononuclear cells and targeted sequencing of AML genes were performed. The data of different groups was compared. Results: A total of 453 newly diagnosed AML patients were enrolled in the study, including 247 males and 206 females with a median age of 49.5 (range,11-85) years. A total of 540 mutations/fusion genes were detected in 289 patients, 29.1% (132/259) of whom with two or more mutations/fusion genes. In all patients, NPM1 was the most common mutation(12.8%), followed by ETO and TET2 mutation (11.92% and 11.04%, respectively) . And WT1 over-expression accounted for 10.6%. Patients over the age of 50 were with a higher frequency of mutations associated with epigenetic modification, 11.93% for ASXL1, 13.99% for DMNT3A, 6.58% for IDH1/IDH2, and 13.17% for TET2. The frequency of DMNT3A mutations was three times higher than that of patients under 50 years of age (P=0.017). In this study, a relatively low proportion of genetic mutations was observed in low-risk karyotype group. In the medium-risk karyotype group, the relatively high mutation frequencies were observed in NPM1, TET2, FLT3-ITD, DNMT3A, ASXL1, and CEBPA genes. In the poor-risk karyotype group, the mutation frequencies of ASXL1, TET2, DNMT3A and PHF6 genes were more than 10%, especially ASXL1 and PHF6 mutation frequencies were significantly higher than other molecular risk stratification groups (P<0.05). Of the 254 patients (56%) with normal karyotype AML (NK-AML), 56 patients were detected to have gene mutations about epigenetic modification. The median OS of this group was worse than that of patients without related mutations, while the median LFS had no significant difference. In patients with NK-AML older than 50 years, the OS and LFS of patients with epigenetic modification related gene mutations was 12 months and 10 months, versus 18 months and 12 months of patients without mutations. Conclusions: The gene mutations frequencies in AML patients with different age and molecular risk stratification groups are different. Epigenetics gene mutation frequencies, such as DNMT3A, ASXL1, IDH1/IDH2 and TET2,are higher in patients older than 50 years. A shorter OS can be observed in older patients(>50 years) with epigenetics gene mutation.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Leucemia Mieloide Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Nucleofosmina , Pronóstico , Adulto Joven
16.
J Microsc ; 270(2): 170-175, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29240235

RESUMEN

This study describes how three-dimensional (3D) human skin tissue is reconstructed, and provides digital anatomical data for the physiological structure of human skin tissue based on large-scale thin serial sections. Human skin samples embedded in paraffin were cut serially into thin sections and then stained with hematoxylin-eosin. Images of serial sections obtained from lighting microscopy were scanned and aligned by the scale-invariant feature transform algorithm. 3D reconstruction of the skin tissue was generated using Mimics software. Fibre content, porosity, average pore diameter and specific surface area of dermis were analysed using the ImageJ analysis system. The root mean square error and mutual information based on the scale-invariant feature transform algorithm registration were significantly greater than those based on the manual registration. Fibre distribution gradually decreased from top to bottom; while porosity showed an opposite trend with irregular average pore diameter distribution. A specific surface area of the dermis showed a 'V' shape trend. Our data suggested that 3D reconstruction of human skin tissue based on large-scale serial sections could be a valuable tool for providing a highly accurate histological structure for analysis of skin tissue. Moreover, this technology could be utilized to produce tissue-engineered skin via a 3D bioprinter in the future.


Asunto(s)
Dermis/anatomía & histología , Epidermis/anatomía & histología , Imagenología Tridimensional , Microscopía/métodos , Humanos , Microtomía , Programas Informáticos , Coloración y Etiquetado
17.
Chem Rev ; 116(16): 9305-74, 2016 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-27459699

RESUMEN

With the arising of global climate change and resource shortage, in recent years, increased attention has been paid to environmentally friendly materials. Trees are sustainable and renewable materials, which give us shelter and oxygen and remove carbon dioxide from the atmosphere. Trees are a primary resource that human society depends upon every day, for example, homes, heating, furniture, and aircraft. Wood from trees gives us paper, cardboard, and medical supplies, thus impacting our homes, school, work, and play. All of the above-mentioned applications have been well developed over the past thousands of years. However, trees and wood have much more to offer us as advanced materials, impacting emerging high-tech fields, such as bioengineering, flexible electronics, and clean energy. Wood naturally has a hierarchical structure, composed of well-oriented microfibers and tracheids for water, ion, and oxygen transportation during metabolism. At higher magnification, the walls of fiber cells have an interesting morphology-a distinctly mesoporous structure. Moreover, the walls of fiber cells are composed of thousands of fibers (or macrofibrils) oriented in a similar angle. Nanofibrils and nanocrystals can be further liberated from macrofibrils by mechanical, chemical, and enzymatic methods. The obtained nanocellulose has unique optical, mechanical, and barrier properties and is an excellent candidate for chemical modification and reconfiguration. Wood is naturally a composite material, comprised of cellulose, hemicellulose, and lignin. Wood is sustainable, earth abundant, strong, biodegradable, biocompatible, and chemically accessible for modification; more importantly, multiscale natural fibers from wood have unique optical properties applicable to different kinds of optoelectronics and photonic devices. Today, the materials derived from wood are ready to be explored for applications in new technology areas, such as electronics, biomedical devices, and energy. The goal of this study is to review the fundamental structures and chemistries of wood and wood-derived materials, which are essential for a wide range of existing and new enabling technologies. The scope of the review covers multiscale materials and assemblies of cellulose, hemicellulose, and lignin as well as other biomaterials derived from wood, in regard to their major emerging applications. Structure-properties-application relationships will be investigated in detail. Understanding the fundamental properties of these structures is crucial for designing and manufacturing products for emerging applications. Today, a more holistic understanding of the interplay between the structure, chemistry, and performance of wood and wood-derived materials is advancing historical applications of these materials. This new level of understanding also enables a myriad of new and exciting applications, which motivate this review. There are excellent reviews already on the classical topic of woody materials, and some recent reviews also cover new understanding of these materials as well as potential applications. This review will focus on the uniqueness of woody materials for three critical applications: green electronics, biological devices, and energy storage and bioenergy.


Asunto(s)
Técnicas Biosensibles/instrumentación , Técnicas Electroquímicas/instrumentación , Tecnología Química Verde , Madera/química , Celulosa/química , Equipos y Suministros Eléctricos , Hidrogeles , Dispositivos Laboratorio en un Chip , Lignina/química , Membranas Artificiales , Nanofibras/química , Papel , Polisacáridos/química , Porosidad , Energía Renovable
18.
Zhonghua Yu Fang Yi Xue Za Zhi ; 52(9): 898-903, 2018 Sep 06.
Artículo en Zh | MEDLINE | ID: mdl-30196635

RESUMEN

Objective: To establish a liquid chromatography-tandem mass spectrometry (LC/MS/MS) method for the determination of microcystin-LR (MC-LR) in drinking water, investigate its removal efficiency during tap water advanced treatment process and analyze its degradation products in the tap water. Methods: Two parallel water samples were collected from each point of tap water advanced treatment process in September 2015, November 2015 and January 2016, respectively, and treated by mixing, filtration, concentration, elution, nitrogen blow and re-dissolvement. The samples were analyzed by LC/MS/MS to determine the MC-LR concentration and its removal efficiency during treatment process. The combination of actual water enrichment (including source water enrichment of 50 times and 1 500 times concentrated, finished water enrichment of 50 times and 2 500 times concentrated) and laboratory simulated water (including the mixture of MC-LR and liquid chlorine in the mass ratio of 1∶10, 1∶20, 1∶100 and 1∶1 000, respectively) were used to qualitative analyze the MC-LR degradation products by Orbitrap mass spectrometry. Results: The linearity of MC-LR ranged from 2 to 200 µg/L with the detection limit of 0.007 9 µg/L and the limit of quantification of 0.026 3 µg/L. The recovery rate of MC-LR from different contration in drinking water were from 94.88%-101.47%. The intra-day precision was 2.51%-7.93% and the intra-day precision was 3.24%-8.41%. The average concentration of MC-LR in source water was (0.631±0.262) µg/L, 94.0% of which can be removed by ozone exposure while the concentrate was (0.038±0.016) µg/L, biological pre-treatment and chlorination. The remaining can hardly be removed by sand filtration, ozone exposure, activated carbon, ultrafiltration and other processes. The MC-LR average concentration in the finished water maintained at about (0.036±0.016) µg/L. Degradation products including hydroxy-microcystin, methyl-hydroxy-microcystin, methyl-microcystin were identified in the laboratory simulated water of the mixture of MC-LR and liquid chlorine in the mass ratio of 1∶10. Conclusion: The established MC-LR detection method can be well applied to the monitoring of MC-LR in drinking water due to its simple pre-treatment process and good methodological validation parameters. The degradation products of treatment processes was different.


Asunto(s)
Agua Potable/análisis , Microcistinas/análisis , Microcistinas/química , Cromatografía Liquida , Monitoreo del Ambiente/métodos , Humanos , Toxinas Marinas , Espectrometría de Masas en Tándem , Purificación del Agua
19.
Zhonghua Gan Zang Bing Za Zhi ; 26(2): 98-101, 2018 Feb 20.
Artículo en Zh | MEDLINE | ID: mdl-29804374

RESUMEN

Objective: To explore the characteristics of tumor recurrence after liver transplantation in patients with hepatocellular carcinoma (HCC) associated with hepatitis B and to analyze the risk factors that influence the recurrence and prognosis. Methods: The clinicopathological and survival data of 162 patients with hepatitis B -associated liver cancer who underwent liver transplantation in Peking University People's Hospital from January 2002 to December 2016 were retrospectively analyzed. The postoperative survival rate (OS) and tumor free survival rate (DFS) was statistically analyzed by using the log-rank test. Univariate analysis was performed for various clinicopathological indicators, and the Cox proportional risk regression model was used for multivariate analysis. Results: Univariate analysis showed that the age of the recipients (P(OS) = 0.047, P(DFS) = 0.045), the maximum tumor size (P < 0.001, P(DFS) < 0.001), preoperative AFP levels (P(OS) < 0.001, P(DFS) < 0.001), preoperative HBV-DNA levels (P(OS) = 0.035, P(DFS) = 0.029), vein tumor thrombosis (P(OS) < 0.001, P(DFS) < 0.001), and tumor differentiation degree (P(OS) <0.001, P(DFS) < 0.001) were associated with overall prognosis and tumor recurrence. Multivariate analysis revealed that preoperative AFP levels (P(OS) = 0.014, P(DFS) = 0.013), the maximum tumor size (P(OS) < 0.001, P(DFS) = 0.001), vein tumor thrombosis (P(OS) = 0.012, P(DFS) < 0.004), and tumor differentiation degree (P(OS) = 0.004, P(DFS) = 0.009) were independent risk factors affecting overall prognosis and tumor recurrence. Conclusion: The major prognostic factors linked to tumor biological characteristics after liver transplantation in HBV-related HCC patients are preoperative AFP levels, the largest tumor size, and vein tumor thrombosis and tumor differentiation degree.


Asunto(s)
Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Trasplante de Hígado/métodos , Recurrencia Local de Neoplasia/prevención & control , Adulto , Carcinoma Hepatocelular/virología , Supervivencia sin Enfermedad , Humanos , Neoplasias Hepáticas/virología , Trasplante de Hígado/efectos adversos , Recurrencia Local de Neoplasia/patología , Pronóstico , Estudios Retrospectivos , Factores de Riesgo
20.
Zhonghua Gan Zang Bing Za Zhi ; 26(12): 933-939, 2018 Dec 20.
Artículo en Zh | MEDLINE | ID: mdl-30669787

RESUMEN

Objective: To evaluate the efficacy and safety of DCV-based DAAs therapy for chronic HCV infected Chinese patients. Methods: An open-label, non-randomized, prospective study was designed. Fifty-two patients with chronic HCV infection were enrolled. Among them, there was one patient after liver transplantation, 2 patients after kidney transplantation, 3 patients with hepatocellular carcinoma, and 4 patients with HBV infection. Thirteen cases with chronic hepatitis C (one compensated cirrhosis) who were negative for resistance-related variants [NS5A RAS (-)] of gene 1b and NS5A were treated with daclatasvir (DCV) + asunaprevir (ASV) for 24 weeks. Twenty-five cases of CHC (six compensated cirrhosis) with GT 1b, 2a, 3a, 3b, 6a were treated with DCV + SOF ± RBV for 24 weeks. 8 cases with decompensated cirrhosis of gene 1b and NS5A RAS(-) were given DCV + SOF + RBV regimen for 12 weeks. Six cases with decompensated cirrhosis, of gene 2a, 1b, 2a, 3a, 3b, were given DCV + SOF + RBV regimen for 24 weeks. HCV RNA, blood routine test, liver and kidney function, and upper abdominal ultrasound/MRI were measured at baseline, 4 weeks of treatment, end of treatment, and 12 weeks of follow-up. The incidence of adverse events and laboratory abnormalities during treatment were recorded. A t-test was used to compare the measurement data between two groups, and analysis of variance was used to compare the measurement data between multiple groups. Results: Sixteen patients (100%) achieved SVR12 after treatment, with 0% recurrence rate. Rapid virological response (RVR) of the four treatment regimens were 76.92%, 54.17%, 87.50%, and 83.33%, respectively, and 32 patients achieved 100% virological response after the completion of treatment. The incidence of adverse events of chronic hepatitis C with cirrhosis and decompensated cirrhosis was 62.5% and 64.29%, respectively. The most common adverse event was fatigue in CHC (25.00%), and elevated indirect bilirubin in decompensated cirrhosis (42.86%). No serious adverse drug events, deaths or adverse reactions occurred. Conclusion: DCV-based DAAs regimen is promising option for the treatment of HCV genotypes, compensated cirrhosis, decompensated cirrhosis, hepatocellular carcinoma, and HCV infection after liver/kidney transplantation in china. Above all, it has high SVR12 with good tolerability and safety profile.


Asunto(s)
Antivirales/uso terapéutico , Genotipo , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Carbamatos , China , Quimioterapia Combinada , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/virología , Humanos , Imidazoles , Recurrencia Local de Neoplasia , Estudios Prospectivos , Pirrolidinas , Resultado del Tratamiento , Valina/análogos & derivados
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