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1.
Int J Biol Macromol ; 256(Pt 1): 128373, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38000590

RESUMO

There is at present an acute need for the construction of biopolymer-based smart packaging material that can be applied for the real-time visual monitoring of food freshness. Herein, a nano-sized substituted imidazolate material (SIM-1) with ammonia-sensitive and antibacterial ability was effectively manufactured and then anchored within corn starch/polyvinyl alcohol (CS/PVA) blend to construct biopolymeric smart active packaging material. The structure, physical and functional performances of CS/PVA-based films with different content of SIM-1 (0.5, 1.0 and 2.0 wt% on CS/PVA basis) were then explored in detail. Results revealed that the incorporated SIM-1 nanocrystals were equally anchored within the CS/PVA matrix owing to the establishment of potent hydrogen-bonding interactions, which produced an obvious improvement in the compatibility of CS/PVA blend film, as well as its mechanical strength, water/oxygen barrier and UV-screening performances. The constructed CS/PVA/SIM-1 blend films further demonstrated superior long-term color stability property, ammonia-sensitive and antibacterial functions. Furthermore, the CS/PVA/SIM-1 blend films were utilized for effectively monitoring the deterioration of shrimp via observable color alteration. The above findings suggested the potential applications of CS/PVA/SIM-1 blend films in smart active packaging.


Assuntos
Álcool de Polivinil , Amido , Amido/química , Álcool de Polivinil/química , Zea mays , Amônia , Antibacterianos/farmacologia , Antibacterianos/química , Embalagem de Alimentos/métodos
2.
Insect Sci ; 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37846895

RESUMO

The rice stem borer (RSB), Chilo suppressalis, a notorious rice pest in China, has evolved a high resistance level to commonly used insecticides. Tetraniliprole, a new anthranilic diamide insecticide, effectively controls multiple pests, including RSB. However, the potential resistance risk of RSB to tetraniliprole is still unknown. In this study, the tetraniliprole-selection (Tet-R) strain was obtained through 10 continuous generations of selection with tetraniliprole 30% lethal concentration (LC30 ). The realized heritability (h2 ) of the Tet-R strain was 0.387, indicating that resistance of RSB to tetraniliprole developed rapidly under the continuous selection of tetraniliprole. The Tet-R strain had a high fitness cost (relative fitness = 0.53). We established the susceptibility baseline of RSB to tetraniliprole (lethal concentration at LC50  = 0.727 mg/L) and investigated the resistance level of 6 field populations to tetraniliprole. All tested strains that had resistance to chlorantraniliprole exhibited moderate- to high-level resistance to tetraniliprole (resistance ratio = 27.7-806.8). Detection of ryanodine receptor (RyR) mutations showed that the Y4667C, Y4667D, I4758M, and Y4891F mutations were present in tested RSB field populations. RyR mutations were responsible for the cross-resistance between tetraniliprole and chlorantraniliprole. Further, the clustered regularly interspaced palindromic repeats (CRISPR) / CRISPR-associated protein 9-mediated genome-modified flies were used to study the contribution of RyR mutations to tetraniliprole resistance. The order of contribution of a single RyR mutation to tetraniliprole resistance was Y4667D > G4915E > Y4667C ≈ I4758M > Y4891F. In addition, the I4758M and Y4667C double mutations conferred higher tetraniliprole resistance than single Y4667C mutations. These results can guide resistance management practices for diamides in RSB and other arthropods.

3.
Artigo em Inglês | MEDLINE | ID: mdl-36901322

RESUMO

For mountainous areas in different regions, the study of the spatial coupling relationship between rural settlements and arable land resources is a key aspect of coordinated rural development. In this study, a spatial coupling relationship model and a Geodetector are introduced to explore the spatial coupling relationship and driving factors of rural settlements and arable land in the alpine canyon region. The nearest neighbor index, Voronoi diagram, and landscape pattern index system based on the geographic grid are used to analyze the spatial differentiation characteristics of rural settlements in the alpine canyon region, and the spatial coupling relationship model is introduced to explore the spatial coupling relationship between rural settlements and arable land. Finally, the driving factors of the coupling relationship are detected based on Geodetector. The results show that (1) the spatial distribution of rural settlements in the study area is "T-shaped" with a relatively regular settlement shape; (2) the population in the alpine canyon region is relatively small, and the conflict between people and land is not prominent in most areas, so the overall coupling situation between rural settlements and farming land is dominated by fewer people and more land; and (3) the spatial coupling between rural settlements and arable land in the alpine canyon region is mainly affected by four types of factors: terrain topography, meteorology, soil and population, and economy. The interaction between the factors has a synergistic enhancement effect. The results of the study provide theoretical support for the development of rural settlements in the alpine canyon region.


Assuntos
População Rural , Solo , Humanos , China
4.
Int J Biol Macromol ; 210: 654-662, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35513104

RESUMO

Bioinspired polydopamine (PDA) nanoparticles were synthesized and explored as functional compatibilizers in polyvinyl alcohol/starch (PVA/ST) matrix to develop high-performance multifunctional packaging film. The effect of the addition of PDA on the microstructural, mechanical, thermal, water vapor barrier, ultraviolet (UV)/high-energy blue light (HEBL) blocking, thermal insulating and antioxidant properties of PVA/ST composite films was fully investigated. Results demonstrated that the added PDA nanoparticles were evenly dispersed in the PVA/ST matrix, providing compact and dense nanocomposite films due to their compatibilization effect. Compared with virgin PVA/ST film, the resulting PVA/ST/PDA nanocomposite films exhibited greatly improved tensile strength, toughness, thermal stability, and water vapor barrier ability. Furthermore, the presence of PDA endowed PVA/ST composite film with excellent UV/HEBL blocking, thermal insulating as well as antioxidant functions. Thus, such high-performance multifunctional nanocomposite films hold the potential of protecting food quality against photothermal oxidative deterioration and extend food shelf life.


Assuntos
Nanopartículas , Álcool de Polivinil , Antioxidantes , Embalagem de Alimentos/métodos , Indóis , Nanopartículas/química , Polímeros , Álcool de Polivinil/química , Amido/química , Vapor
5.
Entropy (Basel) ; 24(2)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35205507

RESUMO

Causality inference is a process to infer Cause-Effect relations between variables in, typically, complex systems, and it is commonly used for root cause analysis in large-scale process industries. Transfer entropy (TE), as a non-parametric causality inference method, is an effective method to detect Cause-Effect relations in both linear and nonlinear processes. However, a major drawback of transfer entropy lies in the high computational complexity, which hinders its real application, especially in systems that have high requirements for real-time estimation. Motivated by such a problem, this study proposes an improved method for causality inference based on transfer entropy and information granulation. The calculation of transfer entropy is improved with a new framework that integrates the information granulation as a critical preceding step; moreover, a window-length determination method is proposed based on delay estimation, so as to conduct appropriate data compression using information granulation. The effectiveness of the proposed method is demonstrated by both a numerical example and an industrial case, with a two-tank simulation model. As shown by the results, the proposed method can reduce the computational complexity significantly while holding a strong capability for accurate casuality detection.

6.
Int J Biol Macromol ; 204: 284-292, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35149089

RESUMO

This work explored biodegradable polyvinyl alcohol/starch (PVA/ST) film compatibilized by rod-like ZnO nanofillers as multifunctional food packaging materials. The influence of rod-like ZnO nanofillers on the microstructural, UV-shielding, antibacterial, mechanical, thermal, together with water barrier performances of PVA/ST composite films was fully studied. Results revealed that rod-like ZnO nanofillers could be uniformly distributed into the PVA/ST matrix, playing the role of compatibilizers to provide compact and dense nanocomposite films. The resulting nanocomposite films presented greatly improved mechanical and water vapor barrier properties as compared to virgin PVA/ST film. Moreover, the well distributed ZnO endowed PVA/ST film with excellent antimicrobial activity against both E. coli and S. aureus, together with outstanding UV-shielding capability meanwhile retaining highly optical transparency (approximately 90%). The developed PVA/ST/ZnO films were tested for packaging fresh-cut carrot slices to prevent microbial infection and prolong their shelf life. These results indicated that the developed highly transparent and multifunctional PVA/ST/ZnO nanocomposite films possess broad application prospects in active food packaging field.


Assuntos
Nanocompostos , Nanopartículas , Óxido de Zinco , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli , Embalagem de Alimentos/métodos , Nanocompostos/química , Nanopartículas/química , Álcool de Polivinil/química , Staphylococcus aureus , Amido , Óxido de Zinco/química
7.
Cell Mol Biol (Noisy-le-grand) ; 66(3): 138-142, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32538760

RESUMO

This study aimed to compare the diagnostic efficacy of MRI and PET/CT in lung cancer of mouse with spinal metastasis. 40 healthy Balb/c nude mice were selected. 0.1 ml of human lung cancer cell A549 bacterial suspension was injected by the left ventricle injection method to establish a lung cancer spinal metastasis model, and the abnormal signs of the nude mice were closely observed. When the body weight was reduced by 20%, micro PET/CT imaging and small coil MRI imaging were applied after intraperitoneal injection of thiopental anesthesia in nude mice. After the imaging was completed, the nude mouse was dissected and the spinal tumor was removed. The nature of spinal metastases was diagnosed by the pathology department. 5 nude mice died of abdominal infection, 2 nude mice had no spinal tumors, and the remaining 33 nude mice were successfully modeled. 33 nude mice were confirmed by pathology to have 64 metastatic vertebral lesions, among them, there were 7 cervical vertebrae, 24 thoracic vertebrae, 16 lumbar vertebrae, 6 sacral vertebrae and 11 caudal vertebrae. The sensitivity of MRI in the diagnosis of spinal metastases was 78.13%, and specificity was 56.25%. The sensitivity of PET/CT for the diagnosis of spinal metastases was 92.19%, and specificity was 78.95%. The specificity and positive predictive value of PET/CT for the diagnosis of spinal metastases were not significantly different from those of MRI (P> 0.05). The sensitivity, accuracy and negative predictive values were significantly higher than those of MRI (P< 0.05). PET/CT is superior to MRI in the diagnosis of spinal metastases, and its sensitivity, accuracy and negative predictive values were significantly higher than those of MRI (P< 0.05). It is worthy to be further promoted in clinical practice.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Coluna Vertebral/secundário , Células A549 , Animais , Peso Corporal , Humanos , Imageamento por Ressonância Magnética , Camundongos Endogâmicos BALB C , Camundongos Nus
8.
Biomed Res Int ; 2020: 9871390, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32076625

RESUMO

Spinal tuberculosis (STB), which is the most frequent and serious form of skeletal TB, is seriously harmful to a patient's life. However, very little research has been conducted on clinical isolates of STB. The purpose of this study was to genotype clinical isolates of Mycobacterium tuberculosis (MTB) from patients with STB, investigate their drug resistance profiles, and determine whether the genotypes and drug resistance patterns share any relationships with the demographic and clinical features of the patients. Preliminary species identification of the MTB strains was performed using a TCH/PNB culture method and multilocus polymerase chain reactions. Of the specimens collected from 85 hospital in-patients with STB at Xiangya Hospital, China, the 56 culture-positive MTB strains we identified were genotyped by spoligotyping. The strains were tested for resistance to anti-tuberculosis drugs (ATDs), and the demographic and clinical features of the patients were analyzed in combination with the genotyping and drug resistance results. Of the 56, cases, 53 involved M. tuberculosis and 3 involved M. bovis. Spoligotyping revealed 27 Beijing-type cases and 29 nonBeijing cases. When patients with STB were relapsing or experiencing systemic toxicity signs/symptoms (STS), the Beijing MTB-type strains predominated (p < 0.05), but when the patients were receiving initial treatment or lacked STS, the nonBeijing type MTB strains dominated. The Beijing and nonBeijing types differed in their resistance patterns to 8 ATDs, and the resistance rate of the Beijing type was higher than that of the nonBeijing type (p < 0.05). The bacteriological features of STB, including genotype and drug resistance, shared close relationships with the clinical features of patients with STB. Our data provide a reference for the diagnosis and treatment of STB.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Genótipo , Mycobacterium tuberculosis/genética , Tuberculose da Coluna Vertebral/microbiologia , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Pequim , China , Feminino , Humanos , Masculino , Mycobacterium bovis/efeitos dos fármacos , Mycobacterium bovis/genética , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
9.
J Org Chem ; 84(18): 12192-12197, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31469283

RESUMO

A highly efficient palladium-catalyzed Sonogashira coupling of benzylic ammonium salts with terminal alkynes is developed. This strategy provides a facile access to a series of internal alkyne derivatives in moderate to excellent yields via C-N bond cleavage and C(sp3)-C(sp) bond formation. The broad substrate scope and high functional group tolerance make this reaction attractive for organic synthesis.

10.
Biomed Res Int ; 2019: 9765253, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30941375

RESUMO

In this retrospective study, charts of inpatients with spinal tuberculosis (STB) treated in large-scale general hospitals in Changsha, Hunan, China, between 2007 and 2016 were reviewed to investigate their clinical characteristics. Demographic, epidemiological and clinical features, imaging findings, treatment methods, and prognosis were summarized and analyzed. There were 1378 patients, 805 males and 573 females, with a mean age of 43.7 years. The mean interval between symptom onset and diagnosis was 16.0 months (range 15 days-240 months). The incidence of back pain, radicular pain and symptoms of systemic toxicity was 92.5%, 40.1%, and 32.1%, respectively. The rate of neurological impairment was 49.9 %. STB was present in two or more vertebrae in 91.1% of patients, with two adjacent vertebrae being involved in 67.9% of them. The lumbar segment (38.2%) was the most frequently affected, followed by the thoracic spine (35.7%). The sacrococcygeal area was the least frequently involved (0.8%). Abscesses were detected in 65.5% of patients. One thousand patients (72.6%) were managed with surgery and 378 (27.4%) with anti-TB drugs only. Cure was achieved in 1215 patients (88.2%), whereas 49 (3.5 %) had relapses. Concomitant pulmonary TB (PTB) was diagnosed in 366 patients (26.6%) and 63 (4.6%) had concomitant diabetes. Compared with the previous five years, the number of older patients, urban patients, and medical staff with STB had increased by 6.1%, 5.2%, and 1.3%, respectively in the five years studied. STB remains a severe public health problem that cannot be ignored. Most of the patients ignored early symptoms and therefore received untimely treatment. Thus, surveillance for and treatment of STB in South-central China requires strengthening. In addition to the current China-wide database of patients with PTB, a China-wide database of patients with STB should also be set up.


Assuntos
Hospitais Gerais , Pacientes Internados , Tuberculose da Coluna Vertebral/epidemiologia , Tuberculose da Coluna Vertebral/patologia , Adolescente , Adulto , Idoso , China/epidemiologia , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Tuberculose da Coluna Vertebral/diagnóstico por imagem , Tuberculose da Coluna Vertebral/terapia , Adulto Jovem
11.
Biosci Rep ; 38(6)2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30459239

RESUMO

BACKGROUND: Previous studies have indicated that osteogenic protein-1 has protective effects on the biological functions of intervertebral disc cells. Hyperosmolarity is an important physicochemical factor within the disc nucleus pulposus (NP) region, which obviously promotes NP cell apoptosis. OBJECTIVE: To study the effects of osteogenic protein-1 (OP-1) on NP cell apoptosis induced by hyperosmolarity and the potential signaling transduction pathway. METHODS: Rat NP cells were cultured in a hyperosmotic medium with or without OP-1 addition for 7 days. Inhibitor 294002 and inhibitor FK-506 were used to investigate the role of the PI3K/Akt/mTOR pathway in this process. NP cell apoptosis were evaluated by cell apoptosis ratio, activity of caspase-3/9 and gene/protein expression of apoptosis-related molecules (Bax, Bcl-2, caspase-3/cleaved caspase-3 and cleaved PARP). RESULTS: OP-1 addition obviously decreased cell apoptosis ratio and caspase-3/9 activity, down-regulated gene/protein expression of pro-apoptosis molecules (Bax, caspase-3/cleaved casepase-3 and cleaved PARP), up-regulated gene/protein expression of anti-apoptosis molecule (Bcl-2) in a hyperosmotic culture. Moreover, OP-1 addition significantly increased protein expression of p-Akt and p-mTOR. Further analysis showed that addition of LY294002 and FK-506 partly attenuated these protective effects of OP-1 against NP cell apoptosis and activation of the PI3K/Akt/mTOR pathway in a hyperosmotic culture. CONCLUSION: OP-1 can attenuate NP cell apoptosis through activating the PI3K/Akt/mTOR pathway in a hyperosmotic culture. The present study sheds a new light on the protective role of OP-1 in regulating disc cell biology and provides some theoretical basis for the application of OP-1 in retarding/regenerating disc degeneration.


Assuntos
Apoptose , Proteína Morfogenética Óssea 7/metabolismo , Núcleo Pulposo/citologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Animais , Células Cultivadas , Núcleo Pulposo/metabolismo , Pressão Osmótica , Ratos , Ratos Sprague-Dawley
12.
World Neurosurg ; 120: e551-e561, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30172062

RESUMO

BACKGROUND: In recent years, increasing numbers of cervical disease cases have been treated with zero-profile devices in anterior cervical discectomy and fusion (ACDF). Its short-term efficacy has been widely recognized; however, the evidence for long-term efficacy remains insufficient. The present study assessed the mid-term and long-term efficacy of zero-profile compared with cage and plate structures in ACDF by analyzing the clinical and radiological outcomes after treatment of cervical diseases with a minimum 2 years of follow-up. METHODS: We conducted a comprehensive database or platform search in PubMed, ISI Web of Science, Embase, and Cochrane Central Register of Controlled Trials using the PRISMA guidelines and identified 10 reports, with 772 patients (375 in the zero-profile group and 397 in the cage and plate group) that met our inclusion criteria. All patients had been followed up for ≥2 years. Two of us used a standardized data collection form to extract relevant data and check its accuracy independently. RESULTS: The zero-profile group had statistically significant (P < 0.05) less intraoperative blood loss, improved postoperative C2-C7 Cobb angle, and decreased incidence of postoperative dysphagia and adjacent segment degeneration compared with the cage and plate group. The operative time, postoperative Japanese Orthopaedic Association score, Neck Disability Index score, and bone fusion rate showed no statistically significant differences between the 2 groups. CONCLUSIONS: The zero-profile and cage and plate structures achieved comparable mid-term and long-term clinical and radiological outcomes in ACDF. In addition, the zero-profile group showed reduced intraoperative blood loss, improved postoperative C2-C7 Cobb angle, and decreased incidence of dysphagia and adjacent segment degeneration complications.


Assuntos
Placas Ósseas , Vértebras Cervicais/cirurgia , Fixadores Internos , Fusão Vertebral/métodos , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Seguimentos , Humanos , Resultado do Tratamento
13.
Mol Med Rep ; 18(1): 1104-1112, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29845278

RESUMO

Osteosarcoma (OS), a common and primary malignant bone tumor, is characterized by highly aggressive potency. Baicalein, a bioactive flavone isolated from Scutellaria baicalensis Georgi, has been shown to inhibit the progression of numerous tumors, including OS. However, the mechanisms by which baicalein protects against OS are still largely unknown. The results of the present study showed that administration of baicalein significantly inhibited the proliferation, migration and invasion and promoted apoptosis in MG­63 and Saos­2 cells. Ezrin was identified as a target gene of microRNA (miR)­183. MG­63 and Saos­2 cells treated with baicalein exhibited increased miR­183 levels and decreased Ezrin expression. Importantly, miR­183 inhibition and Ezrin overexpression abolished the effects of baicalein on MG­63 and Saos­2 cell proliferation, migration, invasion and apoptosis. Taken together, these findings suggest that baicalein inhibits the proliferation, migration and invasion and induces apoptosis in OS cells by activating the miR­183/Ezrin pathway, revealing a novel mechanism underlying anti­OS effects of baicalein.


Assuntos
Neoplasias Ósseas/metabolismo , Proliferação de Células/efeitos dos fármacos , Proteínas do Citoesqueleto/metabolismo , Flavanonas/farmacologia , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , Osteossarcoma/metabolismo , RNA Neoplásico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Proteínas do Citoesqueleto/genética , Humanos , MicroRNAs/genética , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Osteossarcoma/genética , Osteossarcoma/patologia , RNA Neoplásico/genética , Transdução de Sinais/genética
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