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1.
J Microencapsul ; : 1-27, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33047995

RESUMO

Traditional level of fertilizers was used by most farmers in China with the risks about resources wasting, environmental pollution together with soil structure deterioration. It is practicable to tackle the challenges about over-fertilization and low efficiency with microencapsulated soil conditioner (MSC), which clads the water soluble core with natural polymer. Fulvic acid (FA) can be used as core material, because it possesses the characteristics of water-soluble, fertilizer maintenance and expedient monitoring. The morphology, structure and properties of MSC were studied and compared. The particle size of MSC was ranged from 1.58 to 2.14 mm with a similar shape which was obtained by conventional measuring method due to their soft features. This was mainly attributed to the concentration of liquid paraffin and the interaction between shell materials and calcium chloride. FTIR spectra showed that a peak appeared at 1372 cm-1, and this was ascribed to the microcapsules crosslinked and solidified by calcium ions. Sustained release experiment revealed that the microcapsules owned better fertilizer-retaining and water-retaining performances, and FA may be released as long as 750 h. Biodegradation experiments revealed that an obvious pore structure was found on the surface of microspheres after 30 d of degradation, and this was consistent with the sustained release experiment. Pot experiment illustrated that the plants cured with the microcapsules showed significant growth trend and grew up to 9.2 cm with a maximum rate, and this revealed that MSC owned better performance of promoting the growth of crop root.

2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1486-1490, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33067942

RESUMO

OBJECTIVE: To investigate the consistency between pathologic immunohistochemistry assay and flow immunotyping of patients with lymphoma cell leukemia. METHODS: The immunohistochemistry and flow immunotyping data of 31 patients with non-hodgkin lymphoma admitted in our hospital from January 2012 to December 2018 were analyzed retrospectively. The pathologic immunohistochemical expression of lymphatic cells was compared with that of flow immunotyping types, and the change of expression rate of various antigens in the progression of lymphomas into leukemia stage was studied. The characteristics of immune typing and pathologic immunohistochemistry of lymphoblastic leukemia, and their diagnostic value in lymphoblastic leukemia was observed. RESULTS: All patients with lymphoma reached the leukemia stage. The results of flow immunotyping were basically consistent with the results of pathological immunohistochemistry. The pathological immunohistochemistry showed that CD5, CD3, CD99, CD7, CD34, CD43, etc. mainly expressed in the patients with T lymphocyte lymphoma leukemia, of which CD5 showed the highest expression rate and its positive rate was 100%. The flow immunotyping showed that CD7, CD3, CD2, CD5, CD11b, CD34 and HLA-DR was mainly expressed in the patients with T lymphocyte lymphoma leukemia, of which CD7 was the most sensitive and its positive rate was 100 %. Although the antigens expressed in the pathologic immunohistochemistry and flow immunotyping were basically consistent, there were differences in the expression rates of various antigens, CD20, CD79a, BCL-2, CD10, and the Hodgkin's lymphoma cell antigen PAX5 derived from B cells them mainly expressed in BLL patients assay by pathological immunohistochemistry, among the expression rate of CD20 was 100%, which was higher than other antigen expression rate. CD19, CD20, CD22, CD79a, skappa, and early antigen HLA-DR mainly expressed in BLL patients assayed by flow immunotyping, among them CD19 showed a positive rate of 94.7%. The results of immunohistochemistry and flow immunotyping were compared, it was found that 42% of the patients were accompanied by CD20 expression loss, and the survival period of these patients was significantly reduced. CONCLUSION: 25% of patients with T-lymphoma leukemia are accompanied by CD3 expression loss, and 42% of patients with B-cell lymphoma leukemia are accompanied by CD20 expression loss. There is no significant change in survival of T-cell lymphoma leukemia patients with CD3 expression loss, however, the survival period of B-cell lymphoma leukemia patients with CD20 expression loss is significantly shortened.


Assuntos
Leucemia Linfocítica Crônica de Células B , Linfoma , Antígenos HLA-DR , Humanos , Imunofenotipagem , Estudos Retrospectivos
3.
DNA Cell Biol ; 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32991198

RESUMO

Circular RNAs (circRNAs), a novel group of noncoding RNAs, are present in most eukaryotic cells. Different from messenger RNAs, circRNAs have a covalently closed single-stranded stable structure and often act in cell type and tissue-specific manners, indicating that they can be used as biomarkers. With the advance of high-throughput RNA sequencing technology and bioinformatics, a large number of circRNAs have been identified in association with musculoskeletal diseases, but the functions of most circRNAs have not been clarified. circRNAs regulate biological processes by adsorbing microRNA as "sponges," binding to proteins, acting as transcriptional regulators, and participating in translation of proteins. In this study, we discuss the latest understanding of biogenesis and gene regulatory mechanisms of circRNAs with special emphasis on new targets for musculoskeletal disease diagnosis and clinical treatment.

4.
Reprod Toxicol ; 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32998050

RESUMO

Forchlorfenuron (CPPU), a plant growth regulator, is widely used in agriculture. However, its long-term exposure effects on humans, especially neonates, remain unclear. Therefore, we investigated the developmental toxicity of prenatal and postnatal gavage administration of CPPU in rats. Pregnant Sprague-Dawley rats were administered 300 mg/kg/day CPPU by gavage from day 6 of gestation to the cessation of nursing. During weaning, rat offspring were administered 0, 30, 100, or 300 mg/kg/day CPPU for 4 weeks, followed by a 4-week CPPU-free recovery period. There were no significant differences in clinical symptoms, body weight, development indicators, serum biochemical parameters, sex hormone levels, sperm motility, relative organ weights, and histopathological changes among the 0-100 mg/kg/day CPPU groups. In the 300 mg/kg/day CPPU group, female rats exhibited decreased body weight, earlier time of vaginal opening (VO) and first estrus time (FE), elevated estradiol and blood urea nitrogen (BUN) levels, and upregulation of estrogen receptor 1 gene expression, whereas male rats only exhibited increases in serum BUN, creatinine, and glucose levels. Most changes were reversed after the recovery period. Furthermore, the endometrial epithelial height was significantly increased in female rats despite the absence of significant changes in uterine wall thickness and endometrial glands. Thus, CPPU may promote estradiol secretion, resulting in altered VO and FE and adverse effects in prepubertal female rats. These findings may be applied for risk assessment following CPPU exposure in humans.

5.
Biomark Res ; 8: 47, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32963787

RESUMO

Background: To establish and validate a radiomics-based model for predicting liver cirrhosis in patients with hepatitis B virus (HBV) by using non-contrast computed tomography (CT). Methods: This retrospective study developed a radiomics-based model in a training cohort of 144 HBV-infected patients. Radiomic features were extracted from abdominal non-contrast CT scans. Features selection was performed with the least absolute shrinkage and operator (LASSO) method based on highly reproducible features. Support vector machine (SVM) was adopted to build a radiomics signature. Multivariate logistic regression analysis was used to establish a radiomics-based nomogram that integrated radiomics signature and other independent clinical predictors. Performance of models was evaluated through discrimination ability, calibration and clinical benefits. An internal validation was conducted in 150 consecutive patients. Results: The radiomics signature comprised 25 cirrhosis-related features and showed significant differences between cirrhosis and non-cirrhosis cohorts (P < 0.001). A radiomics-based nomogram that integrates radiomics signature, alanine transaminase, aspartate aminotransferase, globulin and international normalized ratio showed great calibration and discrimination ability in the training cohort (area under the curve [AUC]: 0.915) and the validation cohort (AUC: 0.872). Decision curve analysis confirmed the most clinical benefits can be provided by the nomogram compared with other methods. Conclusions: Our developed radiomics-based nomogram can successfully diagnose the status of cirrhosis in HBV-infected patients, that may help clinical decision-making.

6.
Comput Biol Med ; 125: 104006, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32971324

RESUMO

BACKGROUND: Managing bone defects is a critical aspect of total knee arthroplasty. In this study, we compared the metal block and cement-screw techniques for the treatment of Anderson Orthopaedic Research Institute type 2A tibial bone defects from the biomechanical standpoint. METHOD: The metal block and cement-screw techniques were applied to finite element models of 5- and 10-mm tibial bone defects. Biomechanical compatibility was evaluated based on the stress distributions of the proximal tibia and tibial tray. The displacement of the tibial tray and maximum relative micromotion between the tibial stem and tibia were analyzed to assess the stability of the implant. RESULTS: The maximum stress in both the proximal tibia and tibial tray was greater with the cement-screw technique than with the metal block technique. The stress of the proximal lateral tibia with the cement-screw technique was significantly larger than with the metal block technique (p < 0.05). For the 5-mm bone defect, the maximum relative micromotion was lower than the critical value of 150 µm. For the 10-mm defect, the maximum relative micromotion was 128 µm with the metal block technique and 155 µm with the cement-screw technique, with the latter exceeding the critical value. CONCLUSIONS: The cement-screw technique showed superior biomechanical compatibility to the metal block technique and is more suitable for 5-mm bone defects. However, as it may reduce the fixation strength in 10-mm bone defects, the metal block technique is more appropriate in this case.

7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(4): 1272-1277, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32798411

RESUMO

OBJECTIVE: To explore the renal pathology and cytogenetic features in the multiple myeloma (MM) patients with renal impairment. METHODS: The clinical data of newly diagnosed MM patients with renal impairment in our hospital from January 2009 to January 2019 were analyzed retrospectively, and the relationship between FISH results and results of renal pathological exanimation was analyzed statistically by using SPSS 20.0. RESULTS: A total of 20 patients underwent renal biopsy, included 12 males and 8 females. FISH result showed that out of 20 patients, 7 cases presented interstitial nephritis, among which 3 cases were negative for FISH, and in the remaining cases the rate of IgH rearrangement, 1q21 amplification, RB1 deletion, D13S319 deletion, and P53 deletion detection was 42.86%, 28.57%, 28.57%, 28.57% and 14.29% respectively, the detection positive rate was statistically significantly lower as compared with total probe positive rate (P<0.01). There were 6 cases of cast nephropathy, among which IgH rearrangement, the rate of 1q21 amplification, RB1 deletion, D13S319 deletion, and P53 deletion detection was 66.67%, 50%, 66.67%, 50% and 0% respectively. Compared with the total probe positive rate, there was no statistical significance (P>0.05). There were 4 cases of acute tubular necrosis, among which the detection rates of IgH rearrangement, 1q21 amplification, RB1 deletion, D13S319 deletion, and P53 deletion was 100%, 50%, 50%, 25% and 25%, respectively. Compared with the total probe positive rate, there was no statistical significance (P>0.05). There were one case of amyloidosis, and one case of tubular nephropathy with amyloidosis, the detection with 5 probes were all positive. One case of light chain deposition disease was positive for RB1 gene deletion + D13S319 gene deletion. CONCLUSION: FISH in the MM patients with different renal pathological changes is characterized by heterogeneity, which can be used to predict the risk of renal damage and speculate possible renal pathological types to guide prognosis.


Assuntos
Mieloma Múltiplo , Aberrações Cromossômicas , Análise Citogenética , Citogenética , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Estudos Retrospectivos
8.
Medicine (Baltimore) ; 99(31): e21481, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32756174

RESUMO

RATIONALE: Severe bone defect could often occur after removing the fractured fixation plates of comminuted fracture in the distal humerus. The reoperation of internal fixation or conventional total elbow arthroplasty could hardly restore the anatomy structure and function of the elbow. However, a novel exploration of 3-dimensional (3D) printed personalized elbow prosthesis was presented in this work. This is a rare and successful treatment for the severe bone defect after removing the fractured fixation plates of comminuted distal humerus fracture. PATIENT CONCERNS: A 60-year-old male patient was admitted to the hospital with the chief complaint of right elbow joint pain and limitation of motion for 10 years. He suffered from an open reduction with internal fixation surgery 10 years ago due to a fall injury-induced right distal humerus fracture. DIAGNOSES: Plain radiographs and computed tomography scan revealed fracture lines, fracture displacement, and fixator breakage in the right distal humerus. Pain, swelling, and limitation of motion could be found in the physical examination. Fixation failure and nonunion after internal fixation of comminuted distal humerus fracture were considered. INTERVENTIONS: The patient was treated with 3D printed personalized TEA and functional rehabilitation exercises. OUTCOMES: No severe complications were observed during the 36 months follow-up. The patient could complete the daily activities without pain. The hospital for special surgery score increased from 15 points before surgery to 90 points 36 months after surgery. LESSONS: The 3D printed personalized prosthesis could successfully reconstruct the anatomical structures and function of the elbow joint with a severe bone defect. The 3D printed personalized total elbow arthroplasty might provide a feasible method for treating the complex elbow joint diseases in the elderly.


Assuntos
Artroplastia de Substituição do Cotovelo/instrumentação , Prótese de Cotovelo , Fraturas Cominutivas/cirurgia , Fraturas do Úmero/cirurgia , Impressão Tridimensional , Reoperação/instrumentação , Artroplastia de Substituição do Cotovelo/métodos , Placas Ósseas/efeitos adversos , Cotovelo/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Redução Aberta/efeitos adversos , Reoperação/métodos , Resultado do Tratamento
9.
Nat Commun ; 11(1): 4133, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807777

RESUMO

Chromatin organization is critical for cell growth, differentiation, and disease development, however, its functions in peripheral myelination and myelin repair remain elusive. In this report, we demonstrate that the CCCTC-binding factor (CTCF), a crucial chromatin organizer, is essential for Schwann cell myelination and myelin regeneration after nerve injury. Inhibition of CTCF or its deletion blocks Schwann cell differentiation at the pro-myelinating stage, whereas overexpression of CTCF promotes the myelination program. We find that CTCF establishes chromatin interaction loops between enhancer and promoter regulatory elements and promotes expression of a key pro-myelinogenic factor EGR2. In addition, CTCF interacts with SUZ12, a component of polycomb-repressive-complex 2 (PRC2), to repress the transcriptional program associated with negative regulation of Schwann cell maturation. Together, our findings reveal a dual role of CTCF-dependent chromatin organization in promoting myelinogenic programs and recruiting chromatin-repressive complexes to block Schwann cell differentiation inhibitors to control peripheral myelination and repair.


Assuntos
Fator de Ligação a CCCTC/metabolismo , Cromatina/metabolismo , Proteína 2 de Resposta de Crescimento Precoce/metabolismo , Bainha de Mielina/metabolismo , Complexo Repressor Polycomb 2/metabolismo , Animais , Fator de Ligação a CCCTC/genética , Células Cultivadas , Imunoprecipitação da Cromatina , Proteína 2 de Resposta de Crescimento Precoce/genética , Camundongos , Bainha de Mielina/genética , Complexo Repressor Polycomb 2/genética , Ratos , Células de Schwann/metabolismo
10.
Sci Adv ; 6(33): eaaz6477, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32851157

RESUMO

Mutations in the polycomb repressive complex 2 (PRC2) can cause Weaver-like syndrome, wherein a patient cohort exhibits abnormal white matter; however, PRC2 functions in CNS myelination and regeneration remain elusive. We show here that H3K27me3, the PRC2 catalytic product, increases during oligodendrocyte maturation. Depletion of embryonic ectoderm development (EED), a core PRC2 subunit, reduces differentiation of oligodendrocyte progenitors (OPCs), and causes an OPC-to-astrocyte fate switch in a region-specific manner. Although dispensable for myelin maintenance, EED is critical for oligodendrocyte remyelination. Genomic occupancy and transcriptomic analyses indicate that EED establishes a chromatin landscape that selectively represses inhibitory WNT and bone morphogenetic protein (BMP) signaling, and senescence-associated programs. Blocking WNT or BMP pathways partially restores differentiation defects in EED-deficient OPCs. Thus, our findings reveal that EED/PRC2 is a crucial epigenetic programmer of CNS myelination and repair, while demonstrating a spatiotemporal-specific role of PRC2-mediated chromatin silencing in shaping oligodendrocyte identity and lineage plasticity.

11.
J Int Med Res ; 48(7): 300060520926408, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32660291

RESUMO

OBJECTIVE: We performed this meta-analysis to compare the efficacy and toxicity of regorafenib and TAS-102. METHODS: Electronic databases were searched to identify studies comparing the efficacy and safety of regorafenib and TAS-102 in patients with chemotherapy-refractory metastatic colorectal cancer using pooled analyses. RESULTS: Three clinical trials were included in this analysis. Regarding the reasons for treatment discontinuation, regorafenib was significantly associated with disease progression (odds ratio [OR] = 0.33, 95% confidence interval [CI] = 0.21-0.50) and adverse events (OR = 4.38, 95% CI = 2.69-7.13). However, overall (OR = 0.97, 95% CI = 0.81-1.17) and progression-free survival (OR = 1.01, 95% CI = 0.86-1.18) did not significantly differ between the groups. The most common treatment-related adverse events in the regorafenib group were neutropenia (OR = 0.06, 95% CI = 0.03-0.11), hand-foot syndrome (OR = 50.34, 95% CI = 10.44-242.84), and liver dysfunction (OR = 34.51, 95% CI = 8.30-143.43). Conversely, the incidence of thrombocytopenia did not differ between the two groups. CONCLUSIONS: Regorafenib and TAS-102 have similar efficacy but different adverse event profiles. Differences in the toxicity profiles of the two drugs will help guide treatment selection.

12.
Biochem Pharmacol ; 180: 114157, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32687832

RESUMO

Optineurin is a widely expressed protein that possesses multiple functions. Growing evidence suggests that mutation or dysregulation of optineurin can cause several neurodegenerative diseases, including amyotrophic lateral sclerosis, primary open-angle glaucoma, and Huntington's disease, as well as inflammatory digestive disorders such as Crohn's disease. Optineurin engages in vesicular trafficking, receptor regulation, immune reactions, autophagy, and distinct signaling pathways including nuclear factor kappa beta, by which optineurin contributes to cellular death and related diseases, indicating its potential as a therapeutic target. In this review, we discuss the major functions and signaling pathways of optineurin. Furthermore, we illustrate the influence of optineurin mutation or dysregulation to region-specific pathogenesis as well as potential applications of optineurin in therapeutic strategies.

13.
Front Immunol ; 11: 994, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32612601

RESUMO

The DJ-1 protein, known as an oxidative stress sensor, participates in the onset of oxidative stress-related diseases such as cancer, neurodegenerative disorders, type 2 diabetes, and male infertility. Although DJ-1 has been extensively studied for more than two decades, evidence has only recently emerged that it plays a key role in immune and inflammatory disorders. The immune regulatory function of DJ-1 is achieved by modulating the activation of several immune cells including macrophages, mast cells, and T cells via reactive oxygen species (ROS)-dependent and/or ROS-independent mechanisms. This review describes the current knowledge on DJ-1, focusing on its immune and inflammatory regulatory roles, and highlights the significance of DJ-1 as a novel therapeutic target for immune and inflammatory diseases.

14.
Acta Biomater ; 113: 614-626, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32565370

RESUMO

Osteoporosis is one of the most prevalent age-related diseases worldwide and is characterized by a systemic deterioration of bone strength (bone mineral density and bone quality) with a resulting increase in fragility fractures. Due to the complex osteoporotic pathological environment, it is a huge challenge to induce bone regeneration under osteoporosis conditions. In this study, we successfully nanoengineer a bioinspired mineralized hydrogel from the supramolecular assembly of nano-hydroxyapatite, sodium carbonate, and polyacrylic acid, termed as CHAp-PAA. The resultant nanocomposite hydrogels can maintain their initial morphology and mechanical properties under physiological conditions, while exhibiting good primary stability, biocompatibility, bioactivity, and osteoconductivity. We demonstrate that this optimized hydrogel scaffold has shown superior performance for bone marrow stem cells (BMSCs) proliferation, differentiation, and extracellular matrix production in vitro. Remarkably, the mineralized CHAp-PAA hydrogels could be used as scaffolds for the critical-sized bone defect (6.0 mm diameter and 10.0 mm depth) in the osteoporotic rabbit model. Without the delivery of additional therapeutic agents or stem cells, these CHAp-PAA hydrogel scaffolds can improve bone ingrowth and accelerate new bone formation even in complex osteoporotic pathological environments. Therefore, this work presents a type of bioinspired multifunctional mineral hydrogel that offers an alternative strategy to manage osteoporosis. STATEMENT OF SIGNIFICANCE.

15.
Biomed Res Int ; 2020: 2049306, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32566666

RESUMO

Methods: Bilateral VCA of 50 DDH patients and 56 normal volunteers were measured by Mimics software in the 3D method and X-ray in 2D. Two VCA (the upper VCA and the lower VCA) were measured in both two methods. Every VCA was measured by observer A and observer B for twice separately. The statistical analyses of the differences were calculated among the measurements of the VCA. Results: The mean value of the upper VCA measured in 3D was 4.95° ± 0.76° in DDH group and 5.56° ± 0.62° in the normal group with significant difference (t = -6.457, p < 0.01). The VCA of DDH group and normal group measured by 3D was larger than 2D, both the upper VCA and the lower VCA. The differences indicated statistically significant. The mean value of lower VCA was 0.60° smaller than the mean value of upper VCA in normal volunteers. The mean value of the lower VCA was 0.58° larger than the mean value of the upper VCA in DDH patients. Conclusions: Compared to X-ray, 3D reconstruction technology is more accurate without conventional limitations. The lower VCA of DDH patients should be regarded as the femoral intramedullary guide angle in TKA, especially for patients with femoral deformities.

16.
Eur Phys J E Soft Matter ; 43(5): 30, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32474760

RESUMO

A two-dimensional model is developed to simulate dendrite growth and movement in a gravity environment. The model combines the features of cellular automaton and lattice Boltzmann methods. Two sets of distribution functions are adopted to calculate the melt flow and solute transport simultaneously. The fluid force acting on the dendrite is calculated by extending the basic flow simulation at the solid-liquid interface. Incorporating the force interaction between melt flow and solidified dendrite into the algorithm for dendritic growth, the movement of a growing dendrite in the flowing melt can be simulated. After model validation, the coupled model has been applied to simulate the evolution and motion of an individual nucleus that grows into a dendrite in the presence of gravitational force. It is found that the dendrite growth is strongly influenced by the fluid flow, producing an asymmetrical morphology that the dendrite grows faster in the upstream direction, whereas largely slower in the downstream direction. The growth process of dendritic side-branches is modeled in a high settling velocity without any artificial noise introduced. The melt flow triggered by the dendrite motion enhances the growth of the dendrite in the downward direction, which in turn influences the subsequent dendritic translation.

17.
Soft Matter ; 16(24): 5718-5726, 2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32525172

RESUMO

Formation of quasicrystal structures has always been mysterious since the discovery of these magic structures. In this work, the nucleation of decagonal, dodecagonal, heptagonal, and octagonal quasicrystal structures controlled by the coupling among multiple length scales is investigated using a dynamic phase-field crystal model. We observe that the nucleation of quasicrystals proceeds through local rearrangement of length scales, i.e., the generation, merging and stacking of 3-atom building blocks constructed by the length scales, and accordingly, propose a geometric model to describe the cooperation of length scales during structural transformation in quasicrystal nucleation. Essentially, such cooperation is crucial to quasicrystal formation, and controlled by the match and balance between length scales. These findings clarify the scenario and microscopic mechanism of the structural evolution during quasicrystal nucleation, and help us to understand the common rule for the formation of periodic crystal and quasicrystal structures with various symmetries.

18.
J Agric Food Chem ; 68(30): 7819-7829, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32511910

RESUMO

A novel type of temperature and pH dual-stimuli-responsive microspheric soil conditioner was prepared for the controlled release of urea. First, poly(N-isopropylacrylamide-co-methacrylic acid) [P(NIPAM-co-MAA)] was synthesized, and the microspheric soil conditioner was prepared on the basis of chitosan-coated P(NIPAM-co-MAA) via the emulsion cross-linking method. The structure and morphology of the microsphere were characterized by Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance, polarization optical microscopy, and scanning electron microscopy. The microsphere showed controlled release behavior in different temperature and pH conditions, indicating good stimuli responsiveness. The plant experiment revealed that the microsphere can effectively promote plant growth in acidified soil and high-temperature conditions, and the pH value of acidified soil could be improved. In addition, the microsphere possessed good biodegradation property in the soil. Therefore, the multi-responsive microspheric soil conditioner owns a great potential value to amend soil conditions and promote plant growth in agriculture applications.

19.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 49(2): 191-197, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: covidwho-234346

RESUMO

OBJECTIVE: To analyze the dynamic changes of chest CT images of patients with coronavirus disease 2019 (COVID-19). METHODS: Fifty-two cases of COVID-19 were admitted in the First Affiliated Hospital of Zhejiang University School of Medicine. The consecutive chest CT scans were followed up for all patients with an average of 4 scans performed per patient during the hospitalization. The shortest interval between each scan was 2 days and the longest was 7 days. The shape, number and distribution of lung shadows, as well as the characteristics of the lesions on the CT images were reviewed. RESULTS: The obvious shadows infiltrating the lungs were shown on CT images in 50 cases, for other 2 cases there was no abnormal changes in the lungs during the first CT examination. Ground-glass opacities (GGO) were found in 48 cases (92.3%), and 19 cases (36.5%) had patchy consolidation and sub-consolidation, which were accompanied with air bronchi sign in 17 cases (32.7%). Forty one cases (78.8%) showed a thickened leaflet interval, 4 cases (7.6%) had a small number of fibrous stripes. During hospitalization, GGO lesions in COVID-19 patients gradually became rare,the fibrous strip shadows increased and it became the most common imaging manifestation. The lesions rapidly progressed in 39 cases (75.0%) within 6-9 days after admission. On days 10-14 of admission, the lesions distinctly resolved in 40 cases (76.9%). CONCLUSIONS: The chest CT images of patients with COVID-19 have certain characteristics with dynamic changes, which are of value for monitoring disease progress and clinical treatment.


Assuntos
Infecções por Coronavirus , Pandemias , Pneumonia Viral , Tomografia Computadorizada por Raios X , Betacoronavirus/isolamento & purificação , China , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/patologia , Progressão da Doença , Humanos , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/patologia
20.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 49(2): 191-197, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32391663

RESUMO

OBJECTIVE: To analyze the dynamic changes of chest CT images of patients with coronavirus disease 2019 (COVID-19). METHODS: Fifty-two cases of COVID-19 were admitted in the First Affiliated Hospital of Zhejiang University School of Medicine. The consecutive chest CT scans were followed up for all patients with an average of 4 scans performed per patient during the hospitalization. The shortest interval between each scan was 2 days and the longest was 7 days. The shape, number and distribution of lung shadows, as well as the characteristics of the lesions on the CT images were reviewed. RESULTS: The obvious shadows infiltrating the lungs were shown on CT images in 50 cases, for other 2 cases there was no abnormal changes in the lungs during the first CT examination. Ground-glass opacities (GGO) were found in 48 cases (92.3%), and 19 cases (36.5%) had patchy consolidation and sub-consolidation, which were accompanied with air bronchi sign in 17 cases (32.7%). Forty one cases (78.8%) showed a thickened leaflet interval, 4 cases (7.6%) had a small number of fibrous stripes. During hospitalization, GGO lesions in COVID-19 patients gradually became rare,the fibrous strip shadows increased and it became the most common imaging manifestation. The lesions rapidly progressed in 39 cases (75.0%) within 6-9 days after admission. On days 10-14 of admission, the lesions distinctly resolved in 40 cases (76.9%). CONCLUSIONS: The chest CT images of patients with COVID-19 have certain characteristics with dynamic changes, which are of value for monitoring disease progress and clinical treatment.


Assuntos
Infecções por Coronavirus , Pandemias , Pneumonia Viral , Tomografia Computadorizada por Raios X , Betacoronavirus/isolamento & purificação , China , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/patologia , Progressão da Doença , Humanos , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/patologia
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