Effectiveness of Glutamine Oral Care in Reducing Oral Mucositis and Improving Oral Health After Neurosurgery: A Randomized Controlled Trial with Microbiome Analysis.

BACKGROUND Hospital-acquired infections negatively impact the health of inpatients and are highly costly to treat. Oral care reduces the microorganism number in the mouth and lungs and is essential in preventing postoperative oral inflammation, lung infection, and other complications. This study was designed to determine the effects of oral care with glutamine on oral health, oral flora, and incidence of pneumonia in patients after neurosurgery. MATERIAL AND METHODS This was a parallel, double-blind, randomized trial. Patients admitted to the Neurosurgery Department of the hospital from July to October 2021 were selected. Three hundred patients who met the inclusion criteria were randomized into 3 groups. The control group (n=100) received oral care with routine oral nursing methods with saline, whereas the experimental group (n=100) received oral care with 5% glutamine. A compound chlorhexidine group (n=100) was set as a positive control. All patients, care providers, and investigators were blinded to the group assignment. The incidence of local debris, oral mucositis, halitosis, dryness, oral mucositis disorders, and oral flora types were collected and analyzed in all groups. RESULTS The incidence of local debris, oral mucositis, halitosis, dryness, and other oral mucositis disorders in the glutamine oral care group was significantly decreased, compared with that of the control group. Oral flora types in the glutamine and chlorhexidine groups were significantly reduced. CONCLUSIONS Oral care with 5% glutamine after neurosurgery is associated with a lower incidence of oral disorders and pneumonia, and a significant reduction in oral flora.

A modified Prussian blue biosensor with improved stability based on the use of self-assembled monolayers and polydopamine for quantitative L-glutamate detection.

A miniature L-glutamate (L-Glu) biosensor is described based on Prussian blue (PB) modification with improved stability by using self-assembled monolayers (SAMs) technology and polydopamine (PDA). A gold microelectrode (AuME) was immersed in NH2(CH2)6SH-ethanol solution, forming well-defined SAMs via thiol-gold bonding chemistry which increased the number of deposited Prussian blue nanoparticles (PBNPs) and confined them tightly on the AuME surface. Then, dopamine solution was dropped onto the PBNPs surface and self-polymerized into PDA to protect the PB structure from destruction. The PDA/PB/SAMs/AuME showed improved stability through CV measurements in comparison with PB/AuME, PB/SAMs/AuME, and PDA/PB/AuME. The constructed biosensor achieved a high sensitivity of 70.683 nA µM-1 cm-2 in the concentration range 1-476 µM L-Glu with a low LOD of 0.329 µM and performed well in terms of selectivity, reproducibility, and stability. In addition, the developed biosensor was successfully applied to the determination of L-Glu in tomato juice, and the results were in good agreement with that of high-performance liquid chromatography (HPLC). Due to its excellent sensitivity, improved stability, and miniature volume, the developed biosensor not only has a promising potential for application in food sample analysis but also provides a good candidate for monitoring L-Glu level in food production.

Poly(lactic acid) based Pearl Layer Moistureproof Membrane for Flexible Laminated Packaging.

The development of bio-based polymer materials, such as polylactic acid (PLA) -based polymers, is an effective strategy to reduce dependence on petrochemical-based polymers. However, the preparation of bio-based polymers with high barrier properties is a major challenge. To overcome this challenge, a nacreous layer structure with a ' brick and mud ' pattern is mimicked to improve the overall performance of the material. In this paper, Poly (L -lactic acid) (PLLA) and Polypropylene Glycol (PPG) was combined to prepare bio-based polyurethane (PU-PLLA), which is used as the slurry structure of nacreous layer. The bio-based biomimetic composite membrane (PU-PLLA/BN) is then obtained by adding boron nitride (BN, brick structure of pearl layer) to it. The water vapor permeability test results show that the permeability of PU-PLLA material can be reduced by more than 50% by 5 wt.% BN, which is because the addition of BN can increase the length and tortuosity of the gas molecular diffusion path in the composite. Therefore, this pearl-inspired PU-PLLA/BN film has excellent moisture resistance, which opens up a broad road for the practical application of PLLA in flexible laminated packaging.

Phase image correlation spectroscopy for detecting microfluidic dynamics.

It is essential to quantify the physical properties and the dynamics of flowing particles in many fields, especially in microfluidic-related applications. We propose phase image correlation spectroscopy (PICS) as a versatile tool to quantify the concentration, hydro-diameter, and flow velocity of unlabeled particles by correlating the pixels of the phase images taken on flowing particles in a microfluidic device. Compared with conventional image correlation spectroscopy, PICS is minimally invasive, relatively simple, and more efficient, since it utilizes the intrinsic phase of the particles to provide a contrast instead of fluorescent labeling. We demonstrate the feasibility of PICS by measuring flowing polymethylmethacrylate (PMMA) microspheres and yeast in a microfluidic device. We can envisage that PICS will become an essential inspection tool in biomedicine and industry.

Insight into the Mechanisms Driving the Self-Assembly of Functional Interfaces: Moving from Lipids to Charged Amphiphilic Oligomers.

Polymer-stabilized liquid/liquid interfaces are an important and growing class of bioinspired materials that combine the structural and functional capabilities of advanced synthetic materials with naturally evolved biophysical systems. These platforms have the potential to serve as selective membranes for chemical separations and molecular sequencers and to even mimic neuromorphic computing elements. Despite the diversity in function, basic insight into the assembly of well-defined amphiphilic polymers to form functional structures remains elusive, which hinders the continued development of these technologies. In this work, we provide new mechanistic insight into the assembly of an amphiphilic polymer-stabilized oil/aqueous interface, in which the headgroups consist of positively charged methylimidazolium ionic liquids, and the tails are short, monodisperse oligodimethylsiloxanes covalently attached to the headgroups. We demonstrate using vibrational sum frequency generation spectroscopy and pendant drop tensiometery that the composition of the bulk aqueous phase, particularly the ionic strength, dictates the kinetics and structures of the amphiphiles in the organic phase as they decorate the interface. These results show that H-bonding and electrostatic interactions taking place in the aqueous phase bias the grafted oligomer conformations that are adopted in the neighboring oil phase. The kinetics of self-assembly were ionic strength dependent and found to be surprisingly slow, being composed of distinct regimes where molecules adsorb and reorient on relatively fast time scales, but where conformational sampling and frustrated packing takes place over longer time scales. These results set the stage for understanding related chemical phenomena of bioinspired materials in diverse technological and fundamental scientific fields and provide a solid physical foundation on which to design new functional interfaces.

Pegylated liposomal doxorubicin for myeloid neoplasms.

Pegylated liposomal doxorubicin (Peg-Dox) treatment resulted in a good outcome for patients with lymphoma and multiple myeloma, with reduced cardiotoxicity and an improved pharmacokinetic profile when compared to those of conventional doxorubicin. However, the use of Peg-Dox in myeloid neoplasms remains poorly studied. In this study, we first tested the role of Peg-Dox in the killing of myeloid cell lines and of primary myeloid leukemia cells. Then, a Peg-Dox-based protocol was used to treat patients with myeloid neoplasms. The results showed that the Peg-Dox and Peg-Dox-based protocols had a similar killing ability in myeloid cell lines and in primary myeloid leukemia cells compared to that of conventional doxorubicin. The complete remission rate was 87.5% and 100% for patients with refractory/relapsed acute myeloid leukemia and myelodysplastic syndrome with excess blasts, respectively, after treatment with Peg-Dox. All patients developed grade 3 or 4 hematological toxicity and recovered approximately 2 weeks after completing chemotherapy. No deaths or other severe complications were reported. Our results showed that Peg-Dox can be used in the treatment of myeloid neoplasms with high rates of complete remission and with mild complications.

Severe Periodontitis Is Associated with Early-Onset Poststroke Depression Status.

BACKGROUND: Poststroke depression (PSD) is one of the most common complications after ischemic stroke, and periodontitis is associated with depression. However, whether severe periodontitis is associated with early-onset PSD status remains unknown. In this study, we aimed to investigate whether there is an association between severe periodontitis and PSD status in acute ischemic stroke patients. MATERIAL AND METHODS: We recruited 202 acute ischemic stroke patients within 7 days after stroke onset. Pocket depth and clinical attachment loss were assessed by oral examination to define the severe periodontitis. On the basis of diagnosis of PSD status according to DSM-5 criteria and a 24-item Hamilton Depression Rating Scale score greater than or equal to 8 within 2 weeks after stroke onset, we stratified patients into PSD status or non-PSD status groups and identified the independent predictors for the development of PSD status in multivariate logistic analysis. RESULTS: 77 (38.1%) patients were diagnosed as early-onset PSD status. PSD status group showed more severe periodontitis, lower income, lower Barthel Index (BI) score and Montreal Cognitive Assessment score, higher National Institutes of Health Stroke Scale score and modified Rankin scale (mRS) score compared with non-PSD status group. Multivariate logistic regression showed that severe periodontitis (odds ratio 2.401) and NIHSS score (>4, odds ratio 2.130) were independent predictors for early-onset PSD status. CONCLUSIONS: Severe periodontitis is found to be an important independent predictor of early-onset PSD status in patients with acute ischemic stroke, in addition to the well-known prognostic factors such as nonminor stroke assessed by NIHSS greater than 4.

pH-Responsive Janus Film Constructed with Hydrogen-Bonding Assembly and Dopamine Chemistry.

Poly(acrylic acid) (PAA) was partially grafted with dopamine (PAA-dopa), and then layer-by-layer assembled with poly(vinylpyrrolidone) (PVPON) to prepare hydrogen-bonded (PVPON/PAA-dopa) n film. Polydopamine (PDA) was deposited on (PVPON/PAA-dopa) n film in the presence of oxidant, and hence the whole (PVPON/PAA-dopa) nPDA film was cross-linked. (PVPON/PAA-dopa) nPDA could be utilized as a platform to produce the free-standing Janus film because of the easy detaching process and various chemical reactivity of PDA layer. Ag nanoparticles were formed on (PVPON/PAA-dopa) nPDA film by electroless metallization. 1 H,1 H,2 H,2 H-Perfluorodecanethiol (PFDT) was used to further modify the film through Michael addition. After detaching from the substrate, (PVPON/PAA-dopa)20PDA/Ag/PFDT exhibits reversible swelling-shrinking behavior as the pH value changes. This free-standing film shows Janus character, one side is hydrophobic, whereas the other side is hydrophilic. In addition, the hydrophobic surface exhibits a surface-enhanced Raman scattering effect, whereas the hydrophilic side does not.

Polymeric Nanoparticles with a Glutathione-Sensitive Heterodimeric Multifunctional Prodrug for In Vivo Drug Monitoring and Synergistic Cancer Therapy.

Polymeric micelle-based drug delivery systems have dramatically improved the delivery of small molecular drugs, yet multiple challenges remain to be overcome. A polymeric nanomedicine has now been engineered that possesses an ultrahigh loading (59 %) of a glutathione (GSH)-sensitive heterodimeric multifunctional prodrug (HDMP) to effectively co-deliver two synergistic drugs to tumors. An HDMP comprising of chemotherapeutic camptothecin (CPT) and photosensitizer 2-(1-hexyloxyethyl)-2-devinyl pyropheophorbide-α (HPPH) was conjugated via a GSH-cleavable linkage. The intrinsic fluorogenicity and label-free radio-chelation (64 Cu) of HPPH enabled direct drug monitoring by fluorescence imaging and positron emission tomography (PET). Through quantitative PET imaging, HDMP significantly improves drug delivery to tumors. The high synergistic therapeutic efficacy of HDMP-loaded NPs highlights the rational design of HDMP, and presents exciting opportunities for polymer NP-based drug delivery.

AMD3100 and G-CSF disrupt the cross-talk between leukemia cells and the endosteal niche and enhance their sensitivity to chemotherapeutic drugs in biomimetic polystyrene scaffolds.

BACKGROUND: The multidrug resistance of leukemia cells is closely related to the microenvironment. The present leukemia microenvironment models focus on two-dimensional co-culture system in vitro which does not mimic the in vivo cell growth, while the 3D polystyrene (PS) scaffolds have the advantage. Stromal cell derived factor-1 may be involved in the shielding of endosteal niche from leukemia cells by binding to its receptor CXCR4, but the relationship between SDF-1/CXCR4 axis and leukemia cells is unclear. DESIGN AND METHODS: The experiments were built on the 3D PS scaffolds coated with osteoblasts. Stromal cells and MV4-11 cells were plated on the scaffolds. Then G-CSF, AMD3100 and cytarabine were added. Adhesive rate, SDF-1 level, migration state, apoptosis rate, and cell cycle of leukemia cells were observed after incubation at 24h and 48h. RESULTS: G-CSF decreased the level of SDF-1 and inhibited the expression of CXCR4 and promoted stationary phase leukemia cells to enter the mitotic phase and enhanced the killing effect of chemotherapeutic drugs. AMD3100 disrupted the interaction between tumors and matrix, mobilized the leukemia cells to keep away from the protective microenvironment and strengthened the cytotoxic effect of Ara-C. The combination of G-CSF and AMD3100 had stronger effects on killing the leukemia cells induced by Ara-C. CONCLUSION: It demonstrates that AMD3100 and G-CSF may inhibit adhesion and migration abilities of leukemia cells with the bone marrow niche. Both of them inhibit the role of SDF-1/CXCR4 directly or indirectly. Thus inhibiting SDF-1/CXCR4 axis may be helpful to the treatment of refractory AML.

Dual antiplatelet therapy over 6 months increases the risk of bleeding after biodegradable polymer-coated sirolimus eluting stents implantation: insights from the CREATE study.

BACKGROUND: The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation remains controversial. The primary aim of our study was to evaluate the impact of optimal DAPT duration on bleeding events between 6 and 12 months after biodegradable polymer-coated DES implantation. The secondary aim is to determine the predictors and prognostic implications of bleeding. METHODS: This study is a post hoc analysis of the Multi-Center Registry of EXCEL Biodegradable Polymer Drug Eluting Stents (CREATE) study population. A total of 2,040 patients surviving at 6 months were studied, including 1,639 (80.3%) who had received 6-month DAPT and 401 (19.7%) who had received DAPT greater than 6 months. Bleeding events were defined according to the bleeding academic research consortium (BARC) definitions as described previously and were classified as major/minor (BARC 2-5) and minimal (BARC 1). A left censored method with a landmark at 6 months was used to determine the incidence, predictors, and impact of bleeding on clinical prognosis between 6 and 12 months. RESULTS: At 1-year follow-up, patients who received prolonged DAPT longer than 6 months had a significantly higher incidence of overall (3.0% vs. 5.5%, P = 0.021) and major/minor bleeding (1.1% vs. 2.5%, P = 0.050) compared to the patients who received 6-month DAPT. Multivariate analysis showed that being elderly (OR = 1.882, 95% CI: 1.109-3.193, P = 0.019), having diabetes (OR = 1.735, 95% CI: 1.020-2.952, P = 0.042), having a history of coronary artery disease (OR = 2.163, 95% CI: 1.097-4.266, P = 0.026), and duration of DAPT longer than 6 months (OR = 1.814, 95% CI: 1.064-3.091, P = 0.029) were independent predictors of bleeding. Patients with bleeding events had a significantly higher incidence of cardiac death, myocardial infarction, target lesion revascularization, and stent thrombosis. CONCLUSIONS: Prolonged DAPT (greater than 6 months) after biodegradable polymer-coated DES increases the risk of bleeding, and is associated with adverse cardiac events at 1-year follow-up. (J Interven Cardiol 2014;27:119-126).

Selective homing of brain-derived reconstituted lipid nanoparticles to cerebral ischemic area enables improved ischemic stroke treatment.

Lipid nanoparticles (LNPs) hold great promise as carriers for developing drug delivery systems (DDSs) aimed at managing ischemic stroke (IS). Previous research has highlighted the vital role played by the lipid composition and biophysical characteristics of LNPs, influencing their interactions with cells and tissues. This understanding presents an opportunity to engineer LNPs tailored specifically for enhanced IS treatment. We previously introduced the innovative concept of reconstituted lipid nanoparticles (rLNPs), which not only retain the advantages of conventional LNPs but also incorporate lipids from the originating cell or tissue. Brain-derived rLNPs (B-rLNPs) exhibit significantly superior accumulation within the cerebral ischemic region when compared to liver-derived rLNPs (L-rLNPs). The homing effect of B-rLNPs was then employed to construct 3-n-butylphthalide (NBP) loaded DDS (B-rLNPs/NBP) for the treatment of IS. Our results demonstrated that compared with free NBP, B-rLNPs/NBP can significantly reduce infarct volume, neurological deficits, blood-brain barrier (BBB) leakage rate, brain water content, neutrophil infiltration, alleviate pathological structures, and improve the motor function in MCAO/R model. We also proved that B-rLNPs/NBP showed further reinforced protective effects on the same model than free NBP through the regulation of TLR4/MyD88/NF-κB (anti-inflammation) and Bax/Bcl-2 (anti-apoptosis) pathways. This study offers a promising tool towards improved IS treatment.

Multibarrier-penetrating drug delivery systems for deep tumor therapy based on synergistic penetration strategy.

Nanotherapies, valued for their high efficacy and low toxicity, frequently serve as antitumor treatments, but do not readily penetrate deep into tumor tissues and cells. Here we developed an improved tumor-penetrating peptide (TPP)-based drug delivery system. Briefly, the established TPP iNGR was modified to generate a linear NGR peptide capable of transporting nanotherapeutic drugs into tumors through a CendR pathway-dependent, neuropilin-1 receptor-mediated process. Although TPPs have been reported to reach intended tumor targets, they often fail to penetrate cell membranes to deliver tumoricidal drugs to intracellular targets. We addressed this issue by harnessing cell penetrating peptide technology to develop a liposome-based multibarrier-penetrating delivery system (mbPDS) with improved synergistic drug penetration into deep tumor tissues and cells. The system incorporated doxorubicin-loaded liposomes coated with nona-arginine (R9) CPP and cyclic iNGR (CRNGRGPDC) molecules, yielding Lip-mbPDS. Lip-mbPDS tumor-targeting, tumor cell/tissue-penetrating and antitumor capabilities were assessed using CD13-positive human fibrosarcoma-derived cell (HT1080)-based in vitro and in vivo tumor models. Lip-mbPDS evaluation included three-dimensional layer-by-layer confocal laser scanning microscopy, cell internalization/toxicity assays, three-dimensional tumor spheroid-based penetration assays and antitumor efficacy assays conducted in an animal model. Lip-mbPDS provided enhanced synergistic drug penetration of multiple biointerfaces for potentially deep tumor therapeutic outcomes.

pH-sensitive fluorescent dyes: are they really pH-sensitive in cells?

Chemically synthesized near-infrared aza-BODIPY dyes displayed off-on fluorescence at acidic pH (pKa = 6.2-6.6) through the suppression of the photoinduced electron transfer and/or internal charge transfer process. The apparent pKas of the dyes were shifted well above physiological pH in a hydrophobic microenvironment, which led to "turned-on" fluorescence in micelles and liposomes at neutral and basic pH. Bovine serum albumin also activated the fluorescence, though to a much lesser extent. When these small molecular dyes entered cells, instead of being fluorescent only in acidic organelles, the whole cytoplasm exhibited fluorescence, with a signal/background ratio as high as ∼10 in no-wash live-cell imaging. The dye 1-labeled cells remained highly fluorescent even after 3 days. Moreover, slight variations of the dye structure resulted in significantly different intracellular fluorescence behaviors, possibly because of their different cellular uptake and intracellular activation capabilities. After the separation of cellular components, the fraction of plasma membrane and endoplasmic reticulum showed the highest fluorescence, further confirming the fluorescence activation by membrane structures. The fluorescence intensity of these dyes at different intracellular pHs (6.80 and 8.00) did not differ significantly, indicating that intracellular pH did not play a critical role. Altogether, we showed here for the first time that the fluorescence of pH-sensitive aza-BODIPY dyes was switched intracellularly not by acidic pH, but by intracellular membranes (and proteins as well). The excellent membrane permeability, ultrahigh fluorescence contrast ratio, persistent fluorescent signal, and minimal biological interference of dye 1 make it an ideal choice for live-cell imaging and in vivo cell tracking. These findings also imply that the intracellular fluorescence properties of pH-sensitive dyes should be carefully examined before they are used as pH indicators.

Multifunctional polylactic acid biocomposite film for active food packaging with UV resistance, antioxidant and antibacterial properties.

Antibacterial packaging used to control the growth of microorganisms in food is of great value for prolonging the shelf life of food. In this study, a bio-based antibacterial agent PDI based on zwitterionic and stereochemical synergistic antibacterial was designed and synthesized, and it was simultaneously introduced into polylactic acid (PLA) matrix with antioxidant o-vanillin (oVL) and plasticizer glycerol (GL). A series of PLA/oVL/PDI composite membranes with antibacterial, antioxidant and anti-ultraviolet properties were prepared by solution casting method. The results showed that the mechanical properties of the composite film were significantly improved compared with pure PLA (tensile strength increased by 37 %, elongation at break increased by 209 %), which was mainly attributed to the microphase separation structure induced by synthetic bio-based antibacterial agent, which improved the mechanical strength of PLA matrix, and the hydrogen bond formed by glycerol, o-vanillin and carbonyl group in PLA molecules plasticized PLA matrix. At the same time, the antibacterial rate of PLA/oVL/PDI composite membrane against Escherichia coli and Staphylococcus aureus can reach >95 %. Packaging experiments showed that PLA/oVL/PDI series composite films could effectively extend the shelf life of fresh bananas and apples for 5 days, and had great application prospects in preservative food packaging.

Nitric oxide induces S-nitrosylation of CESA1 and CESA9 and increases cellulose content in Arabidopsis hypocotyls.

Nitric oxide (NO), a small signaling gas molecule, participates in several growth and developmental processes in plants. However, how NO regulates cell wall biosynthesis remains unclear. Here, we demonstrate a positive effect of NO on cellulose content that may be related to S-nitrosylation of cellulose synthase 1 (CESA1) and CESA9. Two S-nitrosylated cysteine (Cys) residues, Cys562 and Cys641, which are exposed on the surface of CESA1 and CESA9 and located in the cellulose synthase catalytic domain, were identified to be S-nitrosylated. Meanwhile, Cys641 was located on the binding surface of CESA1 and CESA9, and Cys562 was very close to the binding surface. Cellulose synthase complexes (CSCs) dynamics are closely associated with cellulose content. S-nitrosylation of CESA1 and CESA9 improved particles mobility and thus increased the accumulation of cellulose in Arabidopsis hypocotyl cells. An increase in hemicellulose content as well as an alteration in pectin content facilitated cell wall extension and contributed to cell growth, finally promoting elongation of Arabidopsis hypocotyls. Overall, our work provides a path to investigate the way NO affects the cellulose content of plants.

Sequential Rocket-Mode Bioactivating Ticagrelor Prodrug Nanoplatform Combining Light-Switchable Diphtherin Transgene System for Breast Cancer Metastasis Inhibition.

The increased risk of breast cancer metastasis is closely linked to the effects of platelets. Our previously light-switchable diphtheria toxin A fragment (DTA) gene system, known as the LightOn system, has demonstrated significant therapeutic potential; it lacks antimetastatic capabilities. In this study, we devised an innovative system by combining cell membrane fusion liposomes (CML) loaded with the light-switchable transgene DTA (pDTA) and a ticagrelor (Tig) prodrug. This innovative system, named the sequential rocket-mode bioactivating drug delivery system (pDTA-Tig@CML), aims to achieve targeted pDTA delivery while concurrently inhibiting platelet activity through the sequential release of Tig triggered by reactive oxygen species with the tumor microenvironment. In vitro investigations have indicated that pDTA-Tig@CML, with its ability to sequentially release Tig and pDTA, effectively suppresses platelet activity, resulting in improved therapeutic outcomes and the mitigation of platelet driven metastasis in breast cancer. Furthermore, pDTA-Tig@CML exhibits enhanced tumor aggregation and successfully restrains tumor growth and metastasis. It also reduces the levels of ADP, ATP, TGF-ß, and P-selectin both in vitro and in vivo, underscoring the advantages of combining the bioactivating Tig prodrug nanoplatform with the LightOn system. Consequently, pDTA-Tig@CML emerges as a promising light-switchable DTA transgene system, offering a novel bioactivating prodrug platform for breast cancer treatment.

Poly (lactic acid)-based pH responsive membrane combined with chitosan and alizarin for food packaging.

A poly (lactic acid) (PLA) -based functional partition composite membrane (PLA/CA) containing chitosan (CS) and alizarin (AL) was designed by solution casting method. The PLA/CA membrane contains the antibacterial zone of the edge part (PLA/CS) and the pH response detection zone of the central part (PLA/AL). At the same time, the environmentally friendly plasticizer tributyl citrate (TBC) was added to make the prepared PLA/CA composite membrane have good flexibility and high transparency. The results of FE-SEM and FTIR showed that CS and AL were uniformly dispersed in PLA matrix and had good compatibility with PLA. The antioxidant activities of PLA/CS and PLA/AL composite films were 43.3 % and 72.8 %, respectively. At the same time, the inhibitory rates of PLA/CS membrane against Escherichia coli and Staphylococcus aureus were as high as 87.91 % and 75.17 %, respectively. PLA/AL films exhibit excellent UV barrier properties. When the environmental pH (ammonia and acetic acid vapor) changed repeatedly, the PLA/AL membrane showed reversible color change of yellow under acidic condition and purple under alkaline condition. During the packaging and storage of chicken breast meat, the freshness of chicken breast meat can be detected by the color change of functional PLA/CA composite membrane.

Improving the physicochemical and in vitro hypolipidemic properties of soluble dietary fiber in camellia seed residue by a cellulose degrading fungus YC49.

Camellia seed residue (CSR) is the main by-product after edible oil extraction from camellia seed, which is a potential low-cost source of soluble dietary fiber (SDF). However, the lower yield and functional properties limit the further application of CSR SDF in the food industry. To fully utilize this resource, in this study, the cellulose degrading fungus YC49 was screened and used to modify SDF in CSR. After fermentation with YC49, the physicochemical structure and in vitro hypolipidemic properties of CSR SDF were improved. Scanning electron microscopy, X-ray diffraction, molecular weight distribution and flow properties showed that fermentation endowed F-SDF (after fermentation) with a more porous microstructure, lower crystallinity, smaller molecular weight and higher viscosity. The results of monosaccharide composition and Fourier transform infrared spectroscopy pointed to differences in the monosaccharide percentages and functional group types between CK-SDF (control) and F-SDF. These alterations combined to achieve improvements in the hydration properties and hypolipidemic activities of CSR SDF, including water holding capacity, oil retention capacity, cholesterol adsorption capacity, pancreatic lipase inhibition capacity, and bile acid binding capacity. Overall, the results indicated that YC49 could be used as an ideal strain for the fermentation modification of SDF in CSR, and F-SDF has the potential to serve as a hypolipidemic component in functional foods.

Evaluating occupational exposures of dental nurses: A retrospective study.

Objective: The objective of this study was to investigate occupational blood-borne pathogen exposure among dental nurses and their attitudes toward infected patients, as well as the effectiveness of the training course, to provide a scientific basis for improving the quality of safety management in the dental hospital. Materials and methods: The study was conducted using questionnaires administered from November 2019 to December 2019 in three hospitals in Sichuan Province, China. Frequencies for answers were calculated and presented as percentages. Results: In total, 257 valid questionnaires were returned. Most (61.9%) nurses stated that they were involved in occupational exposure. Among them, 154 had experienced sharp injuries, and the syringe needle was the most common instrument for injuries (45.8%). Twenty-two individuals had mucosal exposure, and the proportion of eye exposure was the highest (90.9%). Only associations between training and mucosal membrane exposure were found; however, the relevance was weak (r = 0.141). Of the participants, 86.4% felt morally responsible for taking care of patients with infectious diseases, and most (92.6%) said they would continue with this career. Conclusion: Occupational exposure, particularly to sharp injuries, was common in medical care among dental nurses; however, vocational training had little effect on their incidence. As dental nurses still have positive attitudes toward patients with infectious diseases, more effective training should be conducted.