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Pectin, a polysaccharide found in plant cell walls, is characterized by a high abundance of hydroxyl groups and carboxylic acid groups, which results in a strong affinity for water and limits its suitability as a film material. This study aimed to modulate the esterification degree of PEC films by adjusting the concentration of acetic anhydride, and assess the impact of acetic anhydride esterification modification on the properties of the resultant PEC films. The results demonstrated successful grafting of acetic anhydride onto the galacturonic acid ring in the PEC molecule through the esterification process. The hydrophobicity, thermal stability, barrier properties, and mechanical properties of the esterified PEC films were investigated. Among the various concentrations tested, the E-PEC-0.25 film exhibited the highest contact angle of 103.46° and tensile strength of 33.44 MPa, showcasing optimal performance. The E-PEC-0.1 film achieved the highest esterification degree of 0.94 and elongation at a break of 21.11 %. It also exhibited the transparency of 11.66 and the lowest water vapor transmission rate of 0.56 g·mm/(m2·h·kpa). Additionally, TGA and DSC tests revealed enhanced thermal stability of the esterification-prepared films. These findings highlight the potential of acetic anhydride tuning as a promising strategy for optimizing pectin film production.
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Anhídridos Acéticos , Interacciones Hidrofóbicas e Hidrofílicas , Pectinas , Pectinas/química , Esterificación , Anhídridos Acéticos/química , Resistencia a la Tracción , TemperaturaRESUMEN
Microbes naturally inhabit bamboo-based materials in outdoor environments, sequentially contributing to their deterioration. Fungi play a significant role in deterioration, especially in environments with abundant water and favorable temperatures. Alkali treatment is often employed in the pretreatment of round bamboo to change its natural elastic and aesthetic behaviors. However, little research has investigated the structure and dynamics of fungal communities on alkali-treated round bamboo during natural deterioration. In this work, high-throughput sequencing and multiple characterization methods were used to disclose the fungal community succession and characteristic alterations of alkali-treated round bamboo in both roofed and unroofed habitats throughout a 13-week deterioration period. In total, 192 fungal amplicon sequence variants (ASVs) from six phyla were identified. The fungal community richness of roofed bamboo samples declined, whereas that of unroofed bamboo samples increased during deterioration. The phyla Ascomycota and Basidiomycota exhibited dominance during the entire deterioration process in two distinct environments, and the relative abundance of them combined was more than 99%. A distinct shift in fungal communities from Basidiomycota dominant in the early stage to Ascomycota dominant in the late stage was observed, which may be attributed to the increase of moisture and temperature during succession and the effect of alkali treatment. Among all environmental factors, temperature contributed most to the variation in the fungal community. The surface of round bamboo underwent continuous destruction from fungi and environmental factors. The total amount of cell wall components in bamboo epidermis in both roofed and unroofed conditions presented a descending trend. The content of hemicellulose declined sharply by 8.3% and 11.1% under roofed and unroofed environments after 9 weeks of deterioration. In addition, the contact angle was reduced throughout the deterioration process in both roofed and unroofed samples, which might be attributed to wax layer removal and lignin degradation. This study provides theoretical support for the protection of round bamboo under natural weathering.
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Importance: Delayed meconium evacuation and delayed achievement of full enteral feeding among premature infants are associated with poor short- and long-term outcomes. Identifying a more effective and safer enema for meconium evacuation is imperative for improving neonatal care. Objective: To examine whether breast milk enemas can shorten the time to complete meconium evacuation and achievement of full enteral feeding for preterm infants. Design, Setting, and Participants: This randomized, open-label, parallel-group, single-center clinical trial was conducted from September 1, 2019, to September 30, 2022, among 286 preterm infants with a gestational age of 23 to 30 weeks in the neonatal ward of the Shengjing Hospital of China Medical University in Shenyang. Interventions: Preterm infants were randomly assigned to receive either breast milk enemas or normal saline enemas 48 hours after birth. Main Outcome and Measures: The primary outcomes were time to complete meconium evacuation and time to achieve full enteral feeding. Secondary outcomes were duration of hospitalization, weight at discharge, and duration of total parenteral nutrition. Intention-to-treat and per-protocol analyses were conducted. Results: In total, 286 preterm infants (mean [SD] gestational age, 198.8 [7.9] days; 166 boys [58.0%]) were eligible and included in this study. A total of 145 infants were randomized to the normal saline group, and 141 were randomized to the breast milk group. The time to achieve complete meconium evacuation was significantly shorter in the breast milk group than in the normal saline group (-2.2 days; 95% CI, -3.2 to -1.2 days). The time to achieve full enteral feeding was also significantly shorter in the breast milk group than in the normal saline group (-4.6 days; 95% CI, -8.0 to -1.2 days). The duration of total parenteral nutrition was significantly shorter in the breast milk group than in the normal saline group (-4.6 days; 95% CI, -8.6 to -1.0 days). There were no clinically notable differences in any other secondary or safety outcomes between the 2 groups. Conclusions and Relevance: In this randomized clinical trial testing the effects of breast milk enema on meconium evacuation, breast milk reduced the time to achieve complete meconium evacuation and achieve full enteral feeding for preterm infants with a gestational age of 23 to 30 weeks. Subgroup analyses highlight the need for tailored interventions based on gestational age considerations. Trial Registration: isrctn.org Identifier: ISRCTN17847514.
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Enema , Recien Nacido Prematuro , Meconio , Leche Humana , Humanos , Enema/métodos , Recién Nacido , Femenino , Masculino , China , Nutrición Enteral/métodos , Edad GestacionalRESUMEN
BACKGROUND: To observe the effects of early gastroscopy examination on cardiovascular event-related indicators such as heart rate (HR), blood pressure, and electrocardiogram (ECG) in elderly patients with acute upper gastrointestinal bleeding. METHODS: Sixty patients with upper gastrointestinal bleeding admitted from July 2022 to December 2022 were selected. Patients with relevant contraindications were excluded. All patients underwent early gastroscopy examination. Among them, 30 patients were aged 60 or above (elderly group) and 30 patients were aged below 60 (non-elderly group). Dynamic blood pressure and ECG recordings were obtained before, during, and after gastroscopy examination to assess changes in HR, blood pressure, and ECG. RESULTS: The HR and blood pressure levels of the elderly group were significantly lower than those of the non-elderly group before, during, and after gastroscopy examination (Pâ <â .05). In the elderly group, blood pressure and HR were higher during gastroscopy examination compared to before, but lower than during the examination afterward, with statistically significant differences (Pâ <â .05). The diastolic blood pressure was lower after the examination compared to before, with statistical significance, while the systolic blood pressure was lower, and the HR was higher after the examination, but without statistical significance (Pâ >â .05). In the non-elderly group, systolic blood pressure and HR were higher during gastroscopy examination compared to before, with statistically significant differences (Pâ <â .05), while diastolic blood pressure was higher but without statistical significance (Pâ >â .05). Blood pressure and HR were lower after the examination compared to during, with statistically significant differences (Pâ <â .05). The occurrence rates of ECG changes were 70% in the elderly group and 30% in the non-elderly group, with a statistically significant difference (χ2â =â 5.45, Pâ =â .02â <â .05). CONCLUSION: Early gastroscopy examination in elderly patients with gastrointestinal bleeding did not result in severe cardiovascular adverse events and was relatively safe. However, special attention should be given to the occurrence of cardiac arrhythmias.
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Hemorragia Gastrointestinal , Gastroscopía , Anciano , Humanos , Persona de Mediana Edad , Gastroscopía/efectos adversos , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiología , Electrocardiografía , Presión Sanguínea , Arritmias Cardíacas/etiologíaRESUMEN
Psoriasis is a chronic inflammatory skin disease. Topical medicines are the preferred treatment for mild to moderate psoriasis, but the effect of excipients used in semi-solid preparations on psoriasis-like skin inflammation is not fully understood. In the present study, we investigated the effect of stearyl alcohol, a commonly used excipient, on imiquimod (IMQ)-induced psoriasis-like skin inflammation in mice. Psoriasis-like skin inflammation was induced by topical IMQ treatment on the back of mice. Skin lesion severity was evaluated by using psoriasis area and severity index (PASI) scores. The skin sections were stained by haematoxylin-eosin and immunohistochemistry. Stearyl alcohol (20% in vaseline) treatment significantly reduced the IMQ-induced increase of PASI scores and epidermal thickness in mice. IMQ treatment increased the number of Ki67- and proliferating cell nuclear antigen (PCNA)-positive cells in the skin, and the increases were inhibited by stearyl alcohol (20% in vaseline) treatment. Stearyl alcohol treatment (1%, 5%, 10% in vaseline) dose-dependently ameliorated IMQ-induced increase of PASI scores and epidermal thickness in mice. Hexadecanol (20% in vaseline), stearic acid (20% in vaseline) and vaseline treatment had no significant effect on IMQ-induced psoriasis-like skin inflammation in mice. In conclusion, stearyl alcohol has the effect of improving IMQ-induced psoriasis-like skin inflammation in mice.
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Dermatitis , Alcoholes Grasos , Psoriasis , Ratones , Animales , Imiquimod/efectos adversos , Psoriasis/inducido químicamente , Psoriasis/tratamiento farmacológico , Dermatitis/patología , Piel , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/patología , Vaselina/efectos adversos , Modelos Animales de Enfermedad , Ratones Endogámicos BALB CRESUMEN
The control of laccase-catalyzed efficiency often relies on the utilization of modifying enzyme molecules and shielding agents. However, their elevated costs or carcinogenicity led to the inability for large-scale application. To address this concern, we found that a low-cost protein from soybean meal can reduce lignin's ineffective adsorption onto enzymes for improving the efficiency of thymol grafting to lignosulfonate. The results demonstrated that by adding 0.5 mg/mL of additional soybean meal protein, the thymol reaction ratio of the modified lignosulfonate (L-0.5 S) significantly boosted from 18.1 % to 35.0 %, with the minimal inhibitory concentrations of the L-0.5 S against Aspergillus niger dramatically improved from 12.5 mg/mL to 3.1 mg/mL. Multiple characterization methods were employed to better understand the benefit of the modification under the addition of the soybean meal protein. The CO and R1-O group content increased from 20.5 % to 37.8 % and from 65.1 % to 75.5 %, respectively. The proposed potential reaction mechanism was further substantiated by the physicochemical properties. The incorporation of soybean meal effectively mitigated the non-specific adsorption of lignosulfonate, resulting in a reduction of the surface area of lignin from 235.0 to 139.2 m2/g. The utilization of soybean meal as a cost-effective and efficient shielding agent significantly enhanced the efficiency of subsequent enzyme catalysis. Consequently, the application of soybean meal in commercial enzyme catalysis holds considerable appeal and amplifies the relevance of this study in preservative industries.
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Lignina , Lignina/análogos & derivados , Proteínas de Soja , Lignina/química , Lacasa/metabolismo , Timol , Adsorción , Harina , Glycine max , CatálisisRESUMEN
Spline functions have received widespread attention in the fields of image sampling and reconstruction. To enhance the performance of splines in reconstruction and reduce the computational burden of solving large linear equations, we propose a family of generalized cardinal polishing splines (GCP-splines) and provide a system of linear equations to obtain the expressions of GCP-splines. First, we propose a cardinal polishing spline basis function with high-precision. Then, we propose a class of GCP-splines and give a general theory of GCP-splines. To calculate the expressions of GCP-splines, we adopt a system of linear equations to obtain the time shifts operator and the convolutional coefficients based on the search spacing and number of terms. Finally, we propose continuous and discrete interpolation models based on GCP-splines, and demonstrate several valuable properties, such as order of approximation and the Riesz basis. To evaluate the performance of GCP-splines, we conduct several experiments on test images from different modalities. The experimental results demonstrate that the GCP-splines for image interpolation and image denoising have better performance and outperform other methods.
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The environmental moisture changes would result in the deformation and cracking of laminated bamboo lumber (LBL) easily due to the unreleased internal stress, leading to poor durability. In this study, a hydrophobic cross-linking polymer with low deformation was successfully fabricated and introduced in the LBL by polymerization and esterification to improve its dimensional stability. In an aqueous solution, the 2-hydroxyethyl methacrylate (HEMA) and Maleic anhydride (MAh) were employed as the base compounds for synthesizing the copolymer of 2-hydroxyethyl methacrylate and maleic acid (PHM). The hydrophobicity and swelling performance of the PHM was adjusted by controlling the reaction temperatures. PHM-modified LBL's hydrophobicity as indicated by the contact angle, increased from 58.5° to 115.2°. The anti-swelling efficiency was also improved. Moreover, multiple characterizations were applied to clarify the structure of PHM and its bonding linkages in LBL. This study demonstrates an efficient avenue to facilitate the dimensional stability of LBL by PHM modification and sheds new light on the efficient utilization of LBL using a hydrophobic polymer with low deformation.
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Bamboo's mechanical and aesthetic properties are significantly influenced by fungi. However, few studies have been conducted to investigate the structure and dynamics of fungal communities in bamboo during its natural deterioration. In this study, fungal community succession and characteristic variations of round bamboo in roofed and unroofed environments over a period of 13 weeks of deterioration were deciphered using high-throughput sequencing and multiple characterization methods. A total of 459 fungal Operational Taxonomic Units (OTUs) from eight phyla were identified. The fungal community's richness of roofed bamboo samples showed an increasing trend, whereas that of unroofed bamboo samples presented a declining trend during deterioration. Ascomycota and Basidiomycota were the dominant phyla throughout the deterioration process in two different environments: Basidiomycota was found to be an early colonizer of unroofed bamboo samples. Principal Coordinates Analysis (PCoA) analysis suggested that the deterioration time had a greater impact on fungal community variation compared to the exposure conditions. Redundancy analysis (RDA) further revealed that temperature was a major environmental factor that contributed to the variation in fungal communities. Additionally, the bamboo epidermis presented a descending total amount of cell wall components in both roofed and unroofed conditions. The correlation analysis between the fungal community and relative abundance of three major cell wall components elucidated that Cladosporium was negatively correlated with hemicellulose in roofed samples, whereas they presented a positive correlation with hemicellulose and a negative correlation with lignin in unroofed samples. Furthermore, the contact angle decreased during the deterioration process in the roofed as well as unroofed samples, which could arise from the degradation of lignin. Our findings provide novel insights into the fungal community succession on round bamboo during its natural deterioration and give useful information for round bamboo protection.
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Round bamboo has aroused much interest in construction for its mechanical properties, but poor biological durability seriously restricts its application. In order to develop a suitable and effective preservative treatment method for round bamboo, copper naphthenate (CuN) was adopted and impregnated into round bamboo using heat-cold procedure. The distribution and retention of copper naphthenate in round bamboo were studied, and the biological durability represented by the mould and decay resistance were investigated. The results showed that the retention and fixation of copper reached 0.39 kgâ m-3 and 85.3%, respectively. Scanning electron microscopy-energy dispersive X-ray spectrometry further disclosed an increasing trend in the composition of CuN from the end inward. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy analyses later revealed that CuN could be fixed on bamboo in the form of hydrogen bond or complex reaction. Statistical analysis showed that the increasing concentration of CuN from 0.3% to 0.5% and 0.8% (calculated as Cu2+ content) has significant contribution against Trametes versicolor and Gloeophyllum trabeum in comparison with the untreated bamboo. Meanwhile, when the concentration of treating solution increased to 0.8 wt%, the resisting efficacy for Aspergillus niger, Penicillium citrinum and Trichoderma viride soared as high as 85.9%, 94.8% and 70.3%, respectively.
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BACKGROUND: WD repeat domain 5 (WDR5) has been indicated to be involved in tumor progression, however, its role in cervical cancer (CC) has not been investigated yet. METHODS: A total of 350 pairs of CC tissues and para-carcinoma tissues (PCT) were collected. Primary human cervical epithelial cells (hCECs) and cancer-associated fibroblasts (CAFs) were isolated from cervical cancer tissues. MM102 was used to block the interaction between WDR5 and mixed lineage leukemia protein-1 (MLL1), and it was used in vivo to investigate its therapeutic value. RESULTS: WDR5 was up-regulated in cervical squamous cell carcinoma (CSCC) tissues compared to that in PCT. C-X-C motif chemokine ligand 8 (CXCL8) was indicated to be the target gene of WDR5. Highly expressed CXCL8 promoted epithelial-mesenchymal transition (EMT) to form CAFs, and enhanced the cytokine secretions in CAFs to promote CSCC progression. CXCL8 expression was regulated by the interaction between WDR5 and MLL1, and blocking the interaction between these two proteins using MM102 significantly suppressed tumor growth in mice models. CONCLUSIONS: WDR5 plays a key role in CSCC progression by inducing CXCL8 expression and promoting the transformation of CAFs from epithelial cells.
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To improve the compatibility and reactivity of lignosulfonate (LS) with epoxy oligomers, the LS was firstly functionalized with anhydride via the carboxylation reaction. The carboxylated lignosulfonate (CLS) reinforced epoxy resin with excellent mechanical and shape memory performance was prepared facilely via distributing the CLS into the combined epoxy monomers of DGEBA and PEGDGE with the aid of water, rather than using the normal organic solvents. The incorporated CLS promoted the curing reaction of epoxy resin. A typical sea-island structure was formed in the cured sample at the CLS content of 5 phr, exhibiting the highest increases in tensile strength, modulus, elongation at break and toughness by 23.8 %, 18.2 %, 217 % and 113 %, respectively, relative to neat epoxy. Interestingly, the incorporation of CLS at a proper amount led to the simultaneous strengthening and toughing effects on cured epoxy resin, which could be attributed to the rigid structure of CLS covalently introduced in the epoxy resin network and the heterogeneous structure formed in the epoxy matrix. The rigid CLS component also restrained the movement of chain segments, consequently, the mechanical stability was enhanced and the fast shape recovery rate of epoxy resin network was slowed down to some extent.
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Resinas Epoxi , Lignina , Ácidos Carboxílicos , Resinas Epoxi/química , Lignina/análogos & derivados , Lignina/química , Solventes , Resistencia a la TracciónRESUMEN
The extension of wood to a wider field has been restrained significantly due to its dimensional instability that arises from variation in moisture content, which in turn brings about the risk of cracking, warping or distortion. This work proposed a novel strategy to stabilize wood by means of the in situ construction of a thermotropic shape memory polymer (SMP) inside wood. The cross-linked copolymer network (PMP) with good shape memory behavior was first investigated based on the reaction of methyl methacrylate (MMA) and polyethylene glycol diacrylate (PEGDA) in a water/ethanol solution; then, the PMP was constructed inside wood via vacuum-pressure impregnation and in situ polymerization. The weight gain, volume increment and morphology observations clearly revealed that the PMP was mainly present in wood cell lumens, cell walls and pits. The presence of PMP significantly enhanced the dimensional stability of and reduced the cracks in wood. The desirable shape recovery abilities of PMP under heating-cooling cycles were considered to be the main reasons for wood dimensional stabilization, because it could counteract the internal stress or retard the shrinkage of cell walls once water was evaporated from the wood. This study provided a novel and reliable approach for wood modification.
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Lignosulfonate (LS) was successfully introduced into the epoxy resin matrix with the aid of ethylene glycol (EG) dissolution. Both the rigid LS and soft EG segments were linked into the cross-linked network structure of epoxy resin via esterification of hydroxyl groups in LS and EG molecules with anhydride. The ultimate properties of cured samples were adjusted effectively by changing the proportion of LS and EG components. Curing reaction and kinetics were analyzed, by which the optimal curing process parameters were determined. Although thermal stability of LS itself was relatively lower than that of neat epoxy, the thermal performance was significantly enhanced for the modified sample of epoxy/LS0.5-EG0.5. At the same time, the flexural strength, flexural modulus and impact strength were found to be increased by 23.1, 35.7 and 15.1% respectively compared with the neat epoxy. In addition, the excellent shape memory behavior and improved mechanical stability with LS addition were exhibited by the cured LS-EG modified specimens. This work reveals that lignin can be used as an efficient functional additive to regulate thermal, mechanical and shape memory properties of epoxy resin.
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Biopolímeros/química , Fenómenos Químicos , Resinas Epoxi/química , Glicol de Etileno/química , Lignina/química , Fenómenos Mecánicos , Materiales Inteligentes/química , Cinética , Ensayo de Materiales , Modelos Teóricos , TermogravimetríaRESUMEN
Bamboo, a natural material, has been widely used in the fields of decoration, architecture and furniture. However, bamboo is easy to mildew and lose its use value. In this paper, the inhibition mechanism and antibacterial activity of a natural antibacterial agent citral on bamboo mould and its anti-mildew effect on bamboo were studied. The results showed that citral could change the shape of mycelium, destroy the integrity of mycelium structure, cell wall and cell membrane structure, thereby causing leakage of nucleic acids, proteins and other substances in the cell, as well as destroy the pH balance of the inside and outside of the cell, to inhibit or kill mould. When the concentration of citral is 100 mg ml-1, the antibacterial rates of citral against Penicillium citrinum (PC), Trichoderma viride (TV), Aspergillus niger (AN) and a hybrid fungi group comprising PC, TV and AN (Hun) were more than 100%. However, compared with the direct effect of citral on mould, the antibacterial property of bamboo treated with citral was significantly reduced, the mildew proof effect can be achieved only if the concentration of citral to treat bamboo is increased to more than twice the concentration of citral directly acting on mould.
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PURPOSE: This study aims at researching the content of hepatitis B virus (HBV) DNA in the breast milk of the mothers carrying HBV and investigating the effects of different feeding methods on mother-to-child transmission (MTCT) of HBV. METHODS: All infants were voluntarily chosen by their mothers and divided into breast-feeding group and formula-feeding group, which were divided into three subgroups, respectively: HBV-DNA negative (HBV-) group, low viral load (LVL) group and high viral load (HVL) group. RESULTS: HBV load in colostrum and mature milk were both significantly lower than in serum (P < 0.001). The positive rate of HBV-DNA in colostrum was positively correlated with HBV load in serum, significantly higher than that of the HBV-Group in colostrum in the LVL Group (P < 0.05), and the HVL Group was significantly higher than the LVL Group (P < 0.001). The analysis of risk factors of HBV infection in infants showed that breast-feeding and HBsAg positive in colostrum did not increase the risks of HBV infection of infants (P > 0.05). CONCLUSION: Breast-feeding is safe for infants with HBV-infected mothers who receive active immunization combined with passive immunization. As well, breast-feeding will neither increase the risks of HBV infection for infants nor weaken their immunity to HBV. However, breast-feeding shall be cautiously applied to pregnant women with high viral load.
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BACKGROUND: Delayed meconium evacuation is an important cause of intestinal dysfunction in preterm infants. There are many methods to induce defecation in preterm infants: however, the effects are controversial. Finding a new intervention method to promote meconium evacuation in premature infants is necessary. Therefore, in the proposed study, the effectiveness of breast milk enema on complete meconium evacuation and time to achieve full enteral feeding will be investigated in preterm infants. METHODS/DESIGN: The study is a randomized, open-label, parallel-group, and single-center clinical trial. A total of 294 preterm infants will be recruited and stratified based on gestational age. Then, the infants will be assigned in a randomized block design to the intervention and control groups with a 1:1 ratio. Preterm infants in the control and intervention groups will receive saline enema and breast milk enema, respectively. The primary outcomes will be the time to achieve complete meconium evacuation from birth and time to achieve full enteral feeding from birth in preterm infants. The secondary outcomes will include hospitalization days, body weight at discharge, duration of total parenteral nutrition, cholestasis, and adverse events. DISCUSSION: The results of this trial will determine whether breast milk enema shortens the time to complete meconium evacuation and the time to achieve full enteral feeding in extremely preterm and preterm infants. Furthermore, the study results may provide a new, safe, inexpensive, and easy-to-use intervention to effectively evacuate meconium in preterm infants. TRIAL REGISTRATION: ISRCTN Registry ISRCTN17847514 . Registered on September 14, 2019.
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Meconio , Leche Humana , Enema/efectos adversos , Femenino , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Recién Nacido de muy Bajo Peso , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
The efficient use of abundant renewable bamboo as high value-added decoration and building materials is of great significance for mitigating carbon dioxide emissions and maintaining sustainable development. The key challenge is to explore efficient and gentle methods to improve the undesirable surface properties of bamboo. Herein, a colorful and superhydrophobic bamboo is gently fabricated by a facile in-situ growth and conversion method based on metal-organic framework (for constructing micro-nano composite structures) and subsequent coating of sodium laurate (for reducing surface energy) at room temperature. The resulting sodium laurate-coated cobalt-nickel double hydroxide layer (CoNi-DH-La) is demonstrated as an efficient superhydrophobic layer to exhibit excellent chemical and mechanical stability. Impressively, the as-obtained CoNi-DH-La-coated bamboo sheet (BS-CoNi-DH-La) shows positive performances in terms of mildew resistance, flame retardancy, and self-cleaning. More importantly, this gentle method can endow bamboo with multiple unfading colors by changing the type of inorganic salts during the preparation process and display good potential for large-scale production.
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Bamboo is a widely used renewable and degradable biomass material; however, its sustainable utilisation is hindered by its susceptibility to mold. The current bamboo anti-mold technology is mainly based on organic chemical agents; these agents can easily induce mold resistance in bamboo with long-term use, and can even adversely affect human health. In the present study, the poly(N-isopropyl acrylamide) (PNIPAm)/citral nanohydrogel was prepared by encapsulating the natural antibiotic citral in PNIPAm for the anti-mold treatment of bamboo. The results revealed that this nanohydrogel exhibited a core-shell system with citral as the 'core' and PNIPAm as the 'shell', an average hydrodynamic diameter of 88.1 nm, and a low critical solution temperature (LCST) of 35.4 °C. After the high-pressure impregnation with the nanohydrogel, the bamboo strips showed excellent control effects toward common bamboo molds. Therefore, the nanohydrogel demonstrated high efficiency and it may become an ideal alternative to organic chemical anti-mold agents, thus showcasing its significant potential in the field of mold prevention for bamboo.