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Starch, a natural polymer, has a complex internal structure. Some starches, such as corn and wheat starches, have well-developed surface pores and internal channels. These channel structures are considered crucial in connecting surface stomata and internal cavities and have adequate space for loading guest molecules. After processing or modification, the starch-containing channel structures can be used for food and drug encapsulation and delivery. This article reviews the formation and determination of starch internal channels, and the influence of different factors (such as starch species and processing conditions) on the channel structure. It also discusses relevant starch preparation methods (physical, chemical, enzymatic, and synergistic), and the encapsulation effect of starch containing internal channels on different substances. In addition, the role of internal channels in regulating the starch digestion rate and other aspects is also discussed here. This review highlights the significant multifunctional applications of starch with a channel structure.
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The limited bioavailability of PAHs in non-aqueous phase liquid (NAPL) limits their degradation. The biodegradation of phenanthrene in n-tetradecane by hydrophilic bacterium Moraxella sp. CFP312 was studied with the assistance of two polymers, chitosan and carboxymethyl cellulose (CMC). Both chitosan and CMC improved the cell hydrophobicity of CFP312 and increased the contact angle of CFP312 cells from 30.4 to 78.5 and 88.5, respectively. However, CMC increased the degradation ratio of phenanthrene from 45 to nearly 100%, while chitosan did not cause any improvement. We found that CMC was more effective than chitosan in promoting CFP312 to stabilize Pickering emulsion. In the bacteria-CMC complex system, oil was dispersed into small droplets to obtain a high emulsification index and large specific surface area. Moreover, according to the microscopic image of the bacteria-CMC emulsion droplet, we observed that the droplet surface was tightly covered by the CFP312 cells. Therefore, CFP312 cells joined with CMC can utilize phenanthrene in oil phase at the oil-water interface. This study will offer a new strategy for effective microbial degradation of hydrophobic compounds in NAPLs by hydrophilic bacteria. KEY POINTS: ⢠Biodegradation of phenanthrene in Pickering emulsions ⢠Pickering emulsions stabilized by hydrophilic CFP312 joined with CMC. ⢠Phenanthrene was degraded by CFP312 at oil-water interface.
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Quitosano , Fenantrenos , Bacterias/metabolismo , Carboximetilcelulosa de Sodio/metabolismo , Quitosano/química , Emulsiones/química , Fenantrenos/metabolismo , Agua/químicaRESUMEN
Polycyclic aromatic hydrocarbons (PAHs) are a class of common environmental pollutants that pose threats to human health. In this study, a mesophilic bacterial strain CFP312 (grown at 15-37 °C, optimal at 30 °C) was isolated from PAHs-contaminated soil samples. It was identified as Moraxella sp. by morphological observation, physiological and biochemical test, and 16S rRNA gene phylogeny analysis. This is the first reported PAHs degrading strains in Moraxella. Degradation analysis showed that 84% and 90% of the loaded phenanthrene (400 mg/L) were degraded within 48 h and 60 h, and the degradation rates reached 1.21 and 1.29 mg/(L·h), respectively. During the degradation of phenanthrene, phenanthrene-3,4-dihydrodiol was detected as an intermediate. Based on this, it was proposed that double oxygenation at the positions 3 and 4 of phenanthrene was the first step of biodegradation. Adaptability of strain CFP312 to different enhanced phenanthrene-degradation systems was tested in aqueous-organic system, micellar aqueous system, and cloud point system. Strain CFP312 showed good adaptability to different systems. In addition, the bacterium can rapidly degrade the phenanthrene in contaminated soil in slurry-aqueous system, indicating great potential in environmental remediation.
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Fenantrenos , Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , Biodegradación Ambiental , Humanos , ARN Ribosómico 16S/genética , Microbiología del SueloRESUMEN
AIMS: To evaluate the mechanism through which nursing leadership impacts patient safety. BACKGROUND: Patient safety has received considerable attention among policymakers, governments and public sectors with the emphasis in health care settings on minimizing the risk to patients. Claims are made leadership plays a crucial role in patient safety. However, the incidents of adverse events are consistently high in hospitals. EVALUATION: Published English-only research articles that examine the mechanism by which nursing leadership impacts patient safety were selected from seven electronic databases and manual searches. Data extraction, quality assessments and analysis were completed for ten research studies. KEY ISSUES: There is evidence of significant mediating effects between nursing leadership and decreased adverse patient outcomes specifically with regard to workplace empowerment, leader-nurse relationship and the quality of the care environment. CONCLUSION: The findings suggest that nursing leadership has a significant indirect impact on patient safety outcomes. From a person-centred perspective, the care environment requires workplace empowerment and effective relationships between leaders and nurses. IMPLICATIONS FOR NURSING MANAGEMENT: To improve patient safety outcomes, managers must strive to emphasize workplace empowerment, leader-nurse relationship and the quality of the care environment. Managers must consider these domains as part of an effective workplace culture.
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Liderazgo , Seguridad del Paciente , Humanos , Lugar de TrabajoRESUMEN
Gastric cancer is the second leading cause of cancer-related death worldwide. Survivin overexpressed in many human cancers as a member of the inhibitor of apoptosis protein family. We found that all samples of normal gastric tissues did not express the protein of survivin, and however, 65% human gastric cancer samples expressed survivin. Positive expression of survivin correlated with differentiation. The proliferation and migration of gastric cancer decreased after downregulation of surviving by RNA interference. Furthermore, downregulation of survivin caused the cell cycle arrest. These suggest that survivin play an important role in gastric cancer and the use of survivin siRNA might become an effective approach to cancer therapy.
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Adenocarcinoma/patología , Biomarcadores de Tumor/análisis , Proteínas Inhibidoras de la Apoptosis/metabolismo , Neoplasias Gástricas/patología , Anciano , Western Blotting , Movimiento Celular , Proliferación Celular , Regulación hacia Abajo , Femenino , Citometría de Flujo , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , SurvivinRESUMEN
OBJECTIVE: To investigate the expression and clinical significance of mismatch repair genes hMLH1 and hMSH2 in sporadic colorectal carcinoma tissues. METHODS: The expression of hMLH1 and hMSH2 proteins was detected in the 63 sporadic colorectal carcinoma samples by immunohistochemical staining, including tumor tissue, adjacent tissue at 3 cm from the carcinoma, and normal tissue at 10 cm away from the tumor. RESULTS: The positive rate of hMLH1 protein expression in the 63 normal colorectal tissues, adjacent tissues and sporadic colorectal carcinoma tissues was 95.2%, 85.7% and 81.0%, respectively. The positive rate of hMLH1 protein expression was significantly lower in the tumor than in normal colorectal tissues (P < 0.05). The positive rate of hMSH2 protein in the 63 normal colorectal tissues, adjacent tissues and sporadic colorectal carcinoma tissues were 76.2%, 66.7% and 52.4%, respectively. The positive rate of hMSH2 protein expression was significantly lower in the tumor than in normal colorectal tissues (P < 0.01). The positive rate of hMLH1 protein expression was significantly higher in the tumor tissue of patients aged younger than 60 years (100%) than that in patients ≥ 60 years (75.0%, P < 0.05). The positive rate of hMLH1 protein expression in the tumor tissue accompanied by lymphatic metastasis was 50.0%, significantly lower than that (93.3%) in tumors without lymphatic metastasis (P < 0.05). The positive rate of hMSH2 protein expression in the tumor tissue of patients aged younger than 60 years was 80.0%, significantly higher than that (43.8%) in the cases ≥ 60 years (P < 0.05). The positive rate of hMSH2 protein expression in the tumor tissues with invasion reaching to the intestinal serosa (61.5%) was significantly higher than that (37.5%) in the tumors invading to submucosa or muscular layer (P < 0.05). There was a positive correlation between the expressions of hMLH1 and hMSH2 proteins in the sporadic colorectal carcinomas. CONCLUSION: There is a certain loss of expression of hMLH1 and hMSH2 proteins in sporadic colorectal carcinoma, and is correlated with the age of patients, lymphatic metastasis and different depth of cancer invasion. HMLH1 and hMSH2 may be used as a useful laboratory marker in clinical judgement of occurrence and development of sporadic colorectal carcinoma.