Effect of the charge rate on the mechanical response of composite graphite electrodes: in situ experiment and mathematical analysis.

The cycling lifespan and coulombic efficiency of lithium-ion batteries are crucial to high C-rate applications. The Li-ion concentration is crucial in determining the mechanical integrity and structural stability of electrodes. In this work, graphite is selected as the working electrode due to its widespread use in the electric vehicle industry. The experimental data have shown that the electrodes with a mass loading of 6.54 mg cm-2 exhibited poor cycling performance and high charge transfer resistance at high charge rates. To explain this phenomenon, an in situ stress measurement system and a C-rate-dependent stress model are established to study the mechanical properties of the composite graphite electrode during the electrochemical process at various C-rates. Moreover, the effect of the Li-ion concentration-dependent modulus and C-rate-dependent partial molar volume is taken into account in the mathematical model. The computational curvature data fit well with the corresponding experimental data, highlighting the importance of considering lithium-ion concentration in mechanical stress. It has been found that stresses along the thickness of the active layer switch between compressive and tensile stresses due to the competition between bending stress and diffusion-induced stress. The stress at the outer surface of the composite graphite electrodes reaches a maximum magnitude of 27.5 MPa at a 1.5C-rate. In contrast, the stress at the interface of the active layer is maximum at a 0.5C-rate due to the existence of more lithium ions. Our study provides a direct insight into the quantitative analysis of electrode stresses at different C-rates.

Glycosylphosphatidylinositol-anchored micronemal antigen (GAMA) interacts with the band 3 receptor to promote erythrocyte invasion by malaria parasites.

Glycosylphosphatidylinositol-anchored micronemal antigen (GAMA) is an erythrocyte binding protein known to be involved in malarial parasite invasion. Although anti-GAMA antibodies have been shown to block GAMA attachment to the erythrocyte surface and subsequently inhibit parasite invasion, little is known about the molecular mechanisms by which GAMA promotes the invasion process. In this study, LC-MS analysis was performed on the erythrocyte membrane to identify the specific receptor that interacts with GAMA. We found that ankyrin 1 and the band 3 membrane protein showed affinity for GAMA, and characterization of their binding specificity indicated that both Plasmodium falciparum and Plasmodium vivax GAMA bound to the same extracellular loop of band 3 (loop 5). In addition, we show the interaction between GAMA and band 3 was sensitive to chymotrypsin. Furthermore, antibodies against band 3 loop 5 were able to reduce the binding activity of GAMA to erythrocytes and inhibit the invasion of P. falciparum merozoites into human erythrocytes, whereas antibodies against P. falciparum GAMA (PfGAMA)-Tr3 only slightly reduced P. falciparum invasion. The identification and characterization of the erythrocyte GAMA receptor is a novel finding that identifies an essential mechanism of parasite invasion of host erythrocytes.

A nomogram for predicting sepsis-associated delirium: a retrospective study in MIMIC III.

OBJECTIVE: To develop a nomogram for predicting the occurrence of sepsis-associated delirium (SAD). MATERIALS AND METHODS: Data from a total of 642 patients were retrieved from the Medical Information Mart for Intensive Care (MIMIC III) database to build a prediction model. Multivariate logistic regression was performed to identify independent predictors and establish a nomogram to predict the occurrence of SAD. The performance of the nomogram was assessed in terms of discrimination and calibration by bootstrapping with 1000 resamples. RESULTS: Multivariate logistic regression identified 4 independent predictors for patients with SAD, including Sepsis-related Organ Failure Assessment(SOFA) (p = 0.004; OR: 1.131; 95% CI 1.040 to 1.231), mechanical ventilation (P < 0.001; OR: 3.710; 95% CI 2.452 to 5.676), phosphate (P = 0.047; OR: 1.165; 95% CI 1.003 to 1.358), and lactate (P = 0.023; OR: 1.135; 95% CI 1.021 to 1.270) within 24 h of intensive care unit (ICU) admission. The area under the curve (AUC) of the predictive model was 0.742 in the training set and 0.713 in the validation set. The Hosmer - Lemeshow test showed that the model was a good fit (p = 0.471). The calibration curve of the predictive model was close to the ideal curve in both the training and validation sets. The DCA curve also showed that the predictive nomogram was clinically useful. CONCLUSION: We constructed a nomogram for the personalized prediction of delirium in sepsis patients, which had satisfactory performance and clinical utility and thus could help clinicians identify patients with SAD in a timely manner, perform early intervention, and improve their neurological outcomes.

Antimicrobial Effect of Epigallocatechin Gallate Against Shewanella putrefaciens ATCC 8071: A Study Based on Cell Membrane and Biofilm.

The study was to evaluate the antimicrobial impacts and biofilm influences on epigallocatechin gallate (EGCG) against Shewanella putrefaciens ATCC 8071. The minimum inhibitory concentration (MIC) of EGCG on S. putrefaciens was 160 µg mL-1. The growth curve exhibited that EGCG had a good antimicrobial activity. EGCG caused damages to the bacterial cell wall and membrane based the intracellular component leakage and cell viability analysis. The damage to the membrane integrity by EGCG has been confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). SEM shows deformation of shape, TEM shows cell membrane and wall damage, and the leakage of cytoplasmic material. The treatment with EGCG at 0.25× and 0.5× MIC resulted in decreased motility and elevated levels of oxidative stress, leading to an increase in biofilm formation. These results demonstrated that EGCG may be used as a natural preservative to reduce S. putrefaciens in fish during cold storage.

Microcirculation evaluation of facial nerve palsy using laser speckle contrast imaging: a prospective study.

OBJECTIVE: Facial nerve palsy (FNP) is a common disease in the otorhinolaryngological department. Besides the main symptom of motionlessness occurring in the ipsilateral facial muscles in FNP, there are other common complaints of numbness, stiffness and tightness in ipsilateral face described by the patients. Based on our pilot study, we further investigated the relevance between these complaints and facial microcirculation. METHOD: Function of facial microcirculation was evaluated by laser speckle contrast imaging (LCSI). Facial perfusion was measured in 143 patients with facial nerve palsy (FNP) at the first visit and follow-up visit under the same conditions. RESULTS: Difference in FNP patients' facial microvascular perfusions between ipsilateral and contralateral side was significant (P = 0.0002613). Facial perfusion of patients with Bell's palsy (P = 00089) and facial nerve tumors (P = 0.025110) was significantly decreasing in the ipsilateral side. Improvement of perfusion could be seen after treatment. CONCLUSION: A positive correlation of FNP severity and microvascular impairment can be noticed. During treatment, patients' ipsilateral perfusion could increase. Therefore, this objective method can measure ipsilateral perfusion in the patients with FNP and the ipsilateral microvascular impairment can be detected through this method.

Low vitamin D levels are associated with cognitive impairment in patients with Hashimoto thyroiditis.

BACKGROUND: Cognitive impairment is commonly observed in patients with Hashimoto thyroiditis (HT). Low levels of vitamin D have been correlated with cognitive impairment in non-HT population. We examined the association of vitamin D levels with cognitive impairment in patients with HT. METHODS: We recruited 194 patients with HT and 200 healthy volunteers. Levels of serum 25-hydroxyvitamin D (25(OH)D) were measured using a competitive protein-binding assay. Cognitive funtion was assessed using Montreal Cognitive Assessment score (MoCA). Subjects with a MoCA scores < 26 are considered as having mild cognitive impairment (MCI). Multivariate analysis was performed using logistic regression models. RESULTS: Fifty-five HT patients (28.4%) were diagnosed as having MCI. Patients with MCI had significantly lower 25(OH)D levels when compared with patients without MCI (33.9 ± 6.2 vs. 44.3 ± 9.6 nmol/L, P < 0.001). Significant differences in 25(OH)D quartiles of HT patients were observed between the patients with MCI and the patients without MCI (P < 0.001). In multivariate analyses, serum 25(OH)D levels (≤ 34.0 and ≥ 47.1 nmol/L) were significantly associated with cognitive impairment in patients with HT (OR 6.279, 95% CI 2.673-14.834, P < 0.001; OR 0.061, 95% CI 0.008-0.491, P = 0.009, respectively). CONCLUSION: Our results demonstrate an important association between serum vitamin D levels and cognitive impairment in patients with HT.

Treatment of thoracic hemorrhage due to rupture of traumatic mediastinal hematoma.

Patients in traffic accidents are usually presented with pain and bleeding due to fractures or soft tissue injury. On some occasions, more severe complications may be triggered by the trauma. A review of the published English language literature reveals no survival case once the traumatic mediastinal hematoma is ruptured. In our case, a 54-year-old man suffering motorcycle accident was admitted to emergency department. Computed tomography scan revealed subdural hematoma combined with posterior mediastinal hematoma. The patient was saved and discharged with a satisfactory outcome. Here we hope to share our treatment experience in dealing with the patient with severe multiple trauma.

[Analgesic and Sedative Effect of Acupuncture Combined with Medicine on Patients Undergiong Cardiac Surgery].

OBJECTIVE: To observe analgesic and sedative effect of acupuncture combined with medicine (ACM) on patients undergiong cardiac surgery. METHODS: A total of 50 patients with cardiac surgery from January 2012 to October 2014 were randomly assigned to the conventional analgesia group (group A) and the ACM analgesia group (group B), 25 in each group. Patients in group A were subjected to analgesia and sedation by injecting dexmedetomidine, while patients in group B were subjected to analgesia and sedation by electro-acupuncture [EA, Shenting (GV24); Yintang (EX-HN3)] combined with injection of dexmedetomidine. Morphine hydrochloride injection was performed when analgesia and sedation effect was ineffective in the two groups. The indicators of patients at different time points in the two groups were observed, such as static and dynamic VAS scores, SAS scores, mean arterial pressure (MAP), heart rate (HR), oxygen saturation (SpO2). The injection dosage of dexmedetomidine and morphine hydrochloride, analgesia satisfaction rate, sedation satisfaction rate, the incidences of adverse reactions during treatment such as bradycardia and low blood pressure, mechanical ventilation time, ICU time, and hospitalization expense were observed and recorded in the two groups. RESULTS: There was no statistical difference in static and dynamic VAS scores, SAS score, MAP, HR and SpO2 between the two groups at different time points (P > 0.05). The injection dosage of dexmedetomidine and morphine hydrochloride was significantly reduced in group B than in group A (P < 0.05). The analgesia satisfaction rate of patients in group B was much higher than that in group A (P < 0.05). The incidence of bradycardia also obviously decreased more in group B than in group A (P < 0.05). There was no statistical difference in patients' sedation satisfaction rate, incidences of low blood pressure, delirium, vomiting; mechanical ventilation time, ICU time, or hospitalization expense between the two groups (P > 0.05). CONCLUSION: The analgesia method of ACM could reduce the dosage of traditional analgesic drugs and the occurrence of partial adverse reactions.

[Application of B-ultrasound monitoring plus gastric insufflation for nasointestinal tube indwelling in critical neurosurgical patients].

OBJECTIVE: To explore the application of B-ultrasound monitoring plus gastric insufflation for nasointestinal tube indwelling in critical neurosurgical patients. METHODS: A total of 96 critical comatose neurosurgical patients indicated for nasointestinal tube indwelling were randomized into three groups of routine (A, n = 32), gastric insufflation (B, n = 31) and B-ultrasound monitoring plus gastric insufflation (C, n = 33). And the position of nasointestinal tube was observed within 24 h and at 72 h in three groups. RESULTS: The general profiles of three groups showed no significant differences (P > 0.05). The proportions of nasointestinal tube passing pylorus within 24 h in three groups were 43.8%, 74.2% and 93.9% respectively. Comparing group C with groups A and B, the differences presented statistical significance. The proportions of nasointestinal tube passing pylorus at 72 h in three groups were 68.8%, 83.9% and 100% respectively. Comparing group C with groups A and B, the differences had statistical significance. CONCLUSION: Refined method of nasointestinal tube indwelling and B-ultrasound monitoring may boost the rate of successful indwelling.It is worth wider promotion and application.

[Epidemiological characteristics and risk factors for patients with catheter-related bloodstream infections in intensive care unit].

OBJECTIVE: To explore the epidemiological characteristics, bacterial composition and risk factors for patients with catheter-related bloodstream infection (CRBSI) in intensive care unit (ICU). METHODS: A prospective survey was conduced for 2 605 ICU patients during January 2010 to December 2013. The clinical data of CRBSI and non-CRBSI patients were compared and their relevant risk factors analyzed. RESULTS: Among them, there were 1 773 cases of arteriovenous catheterization. And 94 cases (5.3%) had CRBSI. The 1 000-day catheter infection rate was 9.8. The mortality rates of CRBSI and non-CRBSI patients were 23.4% and 10.7% respectively. And the difference was statistically significant (χ² = 14.38, P < 0.01). The occurrence of CRBSI was a risk factor for mortality. Logistic regression analysis showed that the occurrence of CRBSI was 3.33 folds for venous catheterization time > 6 days over ≤ 6 days (95% CI: 2.04-5.56), 2.50 folds for trauma patients over non-trauma ones (95% CI: 1.49-4.17), 2.98 folds for malignant tumors patients over non-malignant tumors ones (95% CI: 1.61-5.51) and 4.32 folds for diabetics over non-diabetics (95% CI: 2.07-9.01). For different sites of arteriovenous catheterization, the occurrences of CRBSI were not statistically significant. For CRBSI patients with blood culture, the positive microorganisms were gram-negative bacteria (61.7%), gram-positive bacteria (26%) and fungi (12.3%). CONCLUSION: The occurrence of CRBSI is a risk factor for mortality. And diabetes, trauma and arteriovenous catheterization time > 6 days are risk factors for CRBSI. Comprehensive preventive measures should be taken to reduce the incidence of CRBSI.

Platelet glycoprotein IIb/IIIa antagonists in ischemic stroke patients without endovascular therapy: A meta-analysis.

Platelet glycoprotein (GP) IIb/IIIa antagonists have been employed in selective patients after endovascular therapy (EVT) for acute ischemic stroke (AIS), yet application in patients without EVT is debated. This meta-analysis of randomized controlled studies on AIS patients without EVT assessed the effectiveness and safety of platelet GP IIb/IIIa antagonists compared with traditional antiplatelet or thrombolysis therapy. Articles were retrieved from databases, including PubMed, Web of Science, EMBASE, and Cochrane. The risk of bias and certainty level of evidence were assessed. Fifteen studies were included. GP IIb/IIIa antagonists increased the proportion of patients with modified Rankin Scale (mRS) 0-1 (odd ratio [OR] 1.37, 95% confidence interval [CI] 1.04-1.81, p = 0.03), mRS 0-2 (OR 1.27, 95% CI 1.12-1.46, p = 0.0004), and Barthel Index (BI) 95-100 (OR 1.25, p = 0.005); decreased the proportion of stroke progression within 5 days (OR 0.66, p = 0.006); and lowered the mean mRS score at 90 days (mean difference [MD] -0.43, p = 0.002) and the National Institute of Health stroke scale score at 7 days (MD -1.64, p < 0.00001) compared with conventional treatment. Proportions of stroke recurrence within 90 days (OR 1.20, p = 0.60), any intracranial hemorrhage (aICH) (OR 1.20, p = 0.12), symptomatic intracranial hemorrhage (sICH) (OR 0.91, p = 0.88), and death (OR 0.87, p = 0.25) had no statistical difference between both groups. This meta-analysis finds that compared with traditional antiplatelet or thrombolysis therapy, GP IIb/IIIa antagonists administered within 24-96 h of ischemic stroke onset significantly improve functional prognosis of patients with AIS not receiving EVT, as indicated by mRS and BI at 90 days, and do not increase the incidence of aICH, sICH, and death.

Honokiol alleviates radiation-induced premature ovarian failure via enhancing Nrf2.

BACKGROUND: The ovary is highly sensitive to radiation, and patients receiving radiotherapy are at significant risk of premature ovarian failure (POF). This study aimed to explore the radioprotective effect of honokiol (HKL) on ionizing radiation (IR)-induced POF. METHODS: Female C57BL/6 mice were administered intraperitoneally with vehicle or HKL once daily for 7 days. On day 7, the mice in the IR and HKL+IR groups were exposed to 3.2 Gy whole-body radiation for one hour after the intraperitoneal injection and sacrificed 12 or 72 h after radiation exposure. The gonadosomatic index (GSI) was calculated. Blood samples were collected for enzyme-linked immunosorbent assay (ELISA). Ovaries were harvested for histological examination, immunohistochemistry, immunofluorescence, TUNEL, western blot, and qPCR. The fertility assessment was evaluated by calculating live offspring number. RESULTS: The optimum dose of HKL against radiation was 10 mg/kg via intraperitoneal injection. POF was induced 72 h after irradiation with significantly downregulated proliferating cell nuclear antigen (PCNA). The numbers of primordial and preantral follicles decreased significantly after irradiation (p < .001), whereas the number of atretic follicles increased (p < .001). The serum levels of estradiol (E2 ) and anti-Müllerian hormone (AMH) decreased to 50% of the control group after irradiation (p < .05). Moreover, the GSI after irradiation was 27% lower than in the control group (p < .05). The number of offspring in the IR group dropped by 50% compared with the control group (p < .05). HKL pretreatment protected the animals' fertility, GSI, PCNA, serum levels of E2 and AMH, and the number of primordial and preantral follicles. Significant upregulation of apoptosis-related proteins such as Pho-P53, Bax, Cyto C, C-caspase-3, C-PARP, and pyroptosis-related proteins such as Pho-NF-κB p65, NLRP3, caspase-1, IL-1ß, and IL-18 was observed after irradiation, while the expression of Bcl-2 decreased. HKL pretreatment prevented these changes. After irradiation, malondialdehyde (MDA), Nrf2, and HO-1 were upregulated. HKL treatment activated the expression of Nrf2 and HO-1 and promoted the nucleus translocation of Nrf2. Furthermore, HKL did not affect ovarian reserves under physiological conditions. CONCLUSIONS: HKL ameliorated IR-induced POF by inhibiting apoptosis and pyroptosis by enhancing Nrf2 expression and translocation.

Microglial voltage-dependent anion channel 1 signaling modulates sleep deprivation-induced transition to chronic postsurgical pain.

STUDY OBJECTIVES: This study verified that sleep deprivation before and after skin/muscle incision and retraction (SMIR) surgery increased the risk of chronic pain and investigated the underlying roles of microglial voltage-dependent anion channel 1 (VDAC1) signaling. METHODS: Adult mice received 6 hours of total sleep deprivation from 1 day prior to SMIR until the third day after surgery. Mechanical and heat-evoked pain was assessed before and within 21 days after surgery. Microglial activation and changes in VDAC1 expression and oligomerization were measured. Minocycline was injected to observe the effects of inhibiting microglial activation on pain maintenance. The VDAC1 inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) and oligomerization inhibitor VBIT-4 were used to determine the roles of VDAC1 signaling on microglial adenosine 5' triphosphate (ATP) release, inflammation (IL-1ß and CCL2), and chronicity of pain. RESULTS: Sleep deprivation significantly increased the pain duration after SMIR surgery, activated microglia, and enhanced VDAC1 signaling in the spinal cord. Minocycline inhibited microglial activation and alleviated sleep deprivation-induced pain maintenance. Lipopolysaccharide (LPS)-induced microglial activation was accompanied by increased VDAC1 expression and oligomerization, and more VDAC1 was observed on the cell membrane surface compared with control. DIDS and VBIT-4 rescued LPS-induced microglial ATP release and IL-1ß and CCL2 expression. DIDS and VBIT-4 reversed sleep loss-induced microglial activation and pain chronicity in mice, similar to the effects of minocycline. No synergistic effects were found for minocycline plus VBIT-4 or DIDS. CONCLUSIONS: Perioperative sleep deprivation activated spinal microglia and increases the risk of chronic postsurgical pain in mice. VDAC1 signaling regulates microglial activation-related ATP release, inflammation, and chronicity of pain.

Melatonin inhibits senescence-associated melanin pigmentation through the p53-TYR pathway in human primary melanocytes and the skin of C57BL/6 J mice after UVB irradiation.

UVB exposure accelerates skin aging and pigmentation. Melatonin effectively regulates tyrosinase (TYR) activity and aging. The purpose of this study was to determine the association between premature senescence and pigmentation, and the mechanism of melanin synthesis effected by melatonin. Primary melanocytes were extracted and identified from the male foreskin. To inhibit TYR expression, primary melanocytes were transduced with the lentivirus pLKD-CMV-EGFP-2A-Puro-U6-TYR. The wild-type TYR(+/+) and TYR(-/-) or TYR(+/-) knockout C57BL/6 J mice were used to determine the role of TYR on melanin synthesis in vivo. Results showed that UVB-induced melanin synthesis is dependent on TYR in primary melanocytes and mice. Furthermore, in primary melanocytes pretreated with Nutlin-3 or PFT-α to up or downregulate p53, results showed that premature senescence and melanin synthesis increased in primary melanocytes after UVB irradiation at 80 mJ/cm2, and further increased after being treated with Nutlin-3, while significantly decreased with PFT-α. In addition, melatonin inhibited UVB-induced premature senescence associated with inactivation of p53 and phosphorylation of p53 on Ser15 (ser-15), a decrease of melanin synthesis accompanied by reduced TYR expression. Moreover, skin erythema and pigmentation induced by UVB were reduced in the dorsal and ear skin of mice topically pretreated with 2.5% melatonin. These indicate that melatonin inhibits UVB-induced senescence-associated pigmentation via the p53-TYR pathway in primary melanocytes and prevents pigmentation obviously in the dorsal and ear skin of C57BL/6 J mice after UVB irradiation. KEY MESSAGES: P53 links UVB irradiation-induced senescence and senescence-associated pigmentation and regulates TYR in primary melanocytes after UVB irradiation. Melatonin inhibits senescence-associated pigmentation through the p53-TYR pathway in primary melanocytes. Melatonin prevents skin erythema and melanin pigmentation induced by UVB irradiation in the dorsal and ear skin of C57BL/6J mice.

[The observations of curative efficacy of rhubarb combined with blood purification on treatment patients with severe acute organophosphorus pesticide poisoning].

OBJECTIVE: To observe the curative efficacy of rhubarb, montmorillonite powder combined with blood purification on treatment for patients with severe acute organophosphorus pesticide poisoning (AOPP). METHODS: 39 patients with AOPP were divided into treatment group (received the combined treatment of rhubarb, montmorillonite powder and blood purification on the basis of routine therapy, n = 21) and control group (only received the routine treatment because of financial difficulties or the will of family members, n = 18). The differences of clinical manifestations, curative effects and prognosis between two groups were compared. RESULTS: The time of consciousness recovery, the duration of mechanical ventilation and the length of stay in hospital in treatment group were (6.5 ± 1.3), (7.9 ± 2.0) and (13.1 ± 3.2) days, which were significantly shorter than those [(8.4 ± 2.4), (10.7 ± 2.9) and (16.5 ± 3.7) days] of control group (P < 0.05). In 5, 6 and 7 day after treatment,the cholinesterase (ChE) activities of treatment group were significantly higher than those of control group (P < 0.05). The total amount and using time of atropine and pyraloxime methylchloride in treatment group were significantly smaller and shorter than those in control group (P < 0.05). The death rate of treatment group was [19.0% (4/21)], which were significantly lower than that of control group [19.0% (4/21)] (P < 0.05). CONCLUSION: The combined treatment of rhubarb, montmorillonite powder and blood purification of the AOPP patients has a better curative effect.

Effect of Melissa officinalis L. Essential Oil Nanoemulsions on Structure and Properties of Carboxymethyl Chitosan/Locust Bean Gum Composite Films.

This study aimed to develop active films based on carboxymethyl chitosan (CMCS)/locust bean gum (LBG) films containing Melissa officinalis L. essential oil (MOEO) nanoemulsions. The results showed that the active films incorporated with MOEO nanoemulsion resulted in an increase in the elongation of break, water resistance and improved the film hydrophilicity. Elongation of break increased from 18.49% to 27.97% with the addition of 4% MOEO nanoemulsion. Water resistance was decreased from 56.32% to 25.43%, and water contact angle was increased from 75.13 to 83.86 with the addition of 4% MOEO nanoemulsion. However, the water vapor barrier properties and tensile strength decreased with the addition of MOEO nanoemulsions. The scanning electron microscopic images and Fourier transform infrared spectroscopy results showed that the MOEO was very compatible with the film materials and dispersed evenly in the films. At the same time, the addition of MOEO nanoemulsion significantly enhanced antioxidant and antibacterial activities of C/L-MOEO films. The antioxidant and antimicrobial activities of C/L-MOEO films were increased from 7.16% to 33.81% and 3.52% to 54.50%, respectively. In general, C/L-MOEO film has great application prospects.

Effect of multi-frequency ultrasound assisted thawing on the quality of large yellow croaker (Larimichthys crocea).

The effects of mono-, dual- and tri-frequency ultrasound-assisted thawing (UAT) on the physicochemical quality, water-holding capacity, moisture migration and distribution and myofibrillary structure of frozen large yellow croaker (Larimichthys crocea) were detected. The results indicated that multifrequency UAT treatment significantly increased the thawing rate, maintained the stability of myofibrils and reduced the lipid oxidation. The multifrequency UAT samples had better water-holding capacity (higher water-holding capacity values, lower thawing loss and cooking loss) and physicochemical quality (higher hardness, springiness, resilience, chewiness and lower total volatile basic nitrogen (TVB-N) values, thiobarbituric acid reactive substances (TBARS) values), higher immobilized water content, and lower free water content. Therefore, the results provide a further understanding of the quality stability of frozen large yellow croaker treated by the multifrequency UAT.

The Antimicrobial Effect of Melissa officinalis L. Essential Oil on Vibrio parahaemolyticus: Insights Based on the Cell Membrane and External Structure.

The study was to evaluate the antimicrobial impacts on Melissa officinalis L. essential oil (MOEO) against Vibrio parahaemolyticus. The minimum inhibitory concentration (MIC) of MOEO on Vibrio parahaemolyticus was 1 µL⋅mL-1. The kill-time curve exhibited that MOEO had good antimicrobial activity. The analysis of cellular ingredients leakage and cell viability illustrated that MOEO has destruction to the morphology of the cell membrane. The damage to the membrane integrity by MOEO has been confirmed by transmission and scanning electron microscopy, obvious morphological and ultrastructural changes were observed in the treated bacterial cells. The MOEO at 0.5 µL⋅mL-1 can inhibit the biofilm formation, biofilm motility, and extracellular polysaccharide production. Meanwhile, the qPCR results exhibited MOEO inhibited the expression of virulence genes. The findings showed that MOEO exerted its antimicrobial effect mainly by destroying the membrane, which indicated its potential as a natural food preservative.

Gum tragacanth-sodium alginate active coatings containing epigallocatechin gallate reduce hydrogen peroxide content and inhibit lipid and protein oxidations of large yellow croaker (Larimichthys crocea) during superchilling storage.

The active coatings supplemented with epigallocatechin gallate (EGCG) (0.16 %, 0.32 %, and 0.64 %, respectively) combined with superchilling storage (-3 ± 0.2 °C) were used to reduce hydrogen peroxide (H2O2) content, and inhibit lipid and protein oxidations of large yellow croaker during 42 days of superchilling storage. EGCG coatings delayed lipid and protein oxidations by inhibiting the generation of H2O2, malondialdehyde (MDA) and carbonyl groups, and maintaining a higher Ca2+-ATPase activity and sulfhydryl content. We also observed that EGCG treatments maintained myofibrillar organized secondary structure by keeping higher α-helix content, and also stabilized tertiary structure during superchilling storage. Low-field nuclear magnetic resonance (LF-NMR) revealed that EGCG treatments might improve the association of water molecules with protein for fixed water. In addition, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and scanning electron microscope (SEM) images both showed that these treatments could delay the myofibrillar degradation of fresh fish. Overall, we report that the active coatings containing EGCG treatments protect the lipid and protein of large yellow croaker during superchilling storage.

Effects of single-, dual-, and multi-frequency ultrasound-assisted freezing on the muscle quality and myofibrillar protein structure in large yellow croaker (Larimichthys crocea).

Ultrasound-assisted freezing (UAF) has been proved to be a new technology to improve the quality of frozen foods. Frequency is an important parameter affecting UAF result. This study was to investigate the effects of single-, dual- and multi-frequency UAF on muscle quality and myofibrillar protein structure in large yellow croaker (Larimichthys crocea), providing reference for the application of multi-frequency UAF in frozen foods. Multi-frequency UAF increased the freezing rate and had lower thawing loss, thiobarbituric acid reactive substances (TBARS) value, total volatile basic nitrogen (TVB-N) value, and higher immobilized water content. Multi-frequency UAF had lower carbonyl, higher sulfhydryl content, and more stable myofibrillar protein secondary and tertiary structures. Confocal laser scanning microscopy (CLSM) indicated that the filamentous polymer in muscle fibrin solution with multi-frequency UAF was transformed into more evenly distributed units. In general, multi-frequency UAF significantly improved the freezing rate, reduced lipid oxidation, and maintained the myofibrillar structure.