Melatonin: A potential adjuvant therapy for septic myopathy.

Septic myopathy, also known as ICU acquired weakness (ICU-AW), is a characteristic clinical symptom of patients with sepsis, mainly manifested as skeletal muscle weakness and muscular atrophy, which affects the respiratory and motor systems of patients, reduces the quality of life, and even threatens the survival of patients. Melatonin is one of the hormones secreted by the pineal gland. Previous studies have found that melatonin has anti-inflammatory, free radical scavenging, antioxidant stress, autophagic lysosome regulation, mitochondrial protection, and other multiple biological functions and plays a protective role in sepsis-related multiple organ dysfunction. Given the results of previous studies, we believe that melatonin may play an excellent regulatory role in the repair and regeneration of skeletal muscle atrophy in septic myopathy. Melatonin, as an over-the-counter drug, has the potential to be an early, complementary treatment for clinical trials. Based on previous research results, this article aims to critically discuss and review the effects of melatonin on sepsis and skeletal muscle depletion.

Early immune system alterations in patients with septic shock.

This study aims to investigate the early changes in the immune systems of patients with septic shock. A total of 243 patients with septic shock were included in this study. The patients were classified as survivors (n = 101) or nonsurvivors (n = 142). Clinical laboratories perform tests of the immune system's function. Each indicator was studied alongside healthy controls (n = 20) of the same age and gender as the patients. A comparative analysis of every two groups was conducted. Univariate and multivariate logistic regression analyses were performed to identify mortality risk factors that are independent of one another. In septic shock patients, neutrophil counts, infection biomarkers (C-reactive protein, ferritin, and procalcitonin levels), and cytokines (IL-1ß, IL-2R, IL-6, IL-8, IL-10, and TNF-α) increased significantly. Lymphocyte and their subset counts (T, CD4+ T, CD8+ T, B, and natural killer cell counts), lymphocyte subset functions (the proportions of PMA/ionomycin-stimulated IFN-γ positive cells in CD4+ T cells), immunoglobulin levels (IgA, IgG, and IgM), and complement protein levels (C3 and C4) decreased significantly. Compared to survivors, nonsurvivors had higher levels of cytokines (IL-6, IL-8, and IL-10) but lower levels of IgM, complement C3 and C4, and lymphocyte, CD4+, and CD8+ T cell counts. Low IgM or C3 concentrations and low lymphocyte or CD4+ T cell counts were independent risk factors for mortality. These alterations should be considered in the future development of immunotherapies aimed at treating septic shock.

Holistic sleep improvement strategies for frontline nurses served during a public health emergency (COVID-19) in Wuhan, China: A quasi-experimental study.

AIM: To examine effects of holistic sleep improvement strategies on frontline nurses who served in Wuhan, China, during a public health emergency (COVID-19). DESIGN: A pre-post-test design with single group was conducted with a convenience sample applied the Transparent Reporting of Evaluations with Non-randomized Designs statement. METHODS: Fifty-two nurses were recruited from a COVID-19 designated hospital, receiving holistic sleep improvement intervention, which concentrated on scientific human resource management, comfortable sleep environment establishment, self-relaxation and self-adjustment training and humanistic care. Data was collected at baseline and 4-week follow-up post intervention using self-reported questionnaires. RESULTS: The total score of Pittsburgh Sleep Quality Index scale was 8.69 ± 4.346 at baseline. After 4 weeks of follow-up, the score statistically significantly decreased to 7.48 ± 3.691. Subjective sleep quality (p = .016), sleep efficiency (p = .015), sleep disturbances (p = .007) were statistically significantly improved after the intervention, while there were no statistically significant differences in sleep latency (p = .205), sleep duration (p = .375), sleep medication (p = .723) or daytime dysfunction (p = .747).

Ibrutinib protects against acute lung injury via inhibiting NLRP3/Caspase-1 in septic mice model.

Acute lung injury is a severe complication of sepsis with high mortality in ICU. Increasing evidences have showed that Ibrutinib, a Bruton's Tyrosine kinase inhibitor, plays a critical role in numerous inflammation-related diseases. However, its therapeutic effect and mechanism in sepsis induced acute lung injury remain unclear. In this study, cecal ligation puncture (CLP) was performed on male C57BL/6 J mice to establish a mouse model of sepsis. Ibrutinib (50 mg/kg/d) was administered by gavage 1 day before CLP, once a day, for 3 consecutive days. on the fourth day mice were given one dose of ibrutinib 2 h before CLP induction, and another dose was given 24 h later. Histopathological examination of lung tissues was performed at 72 h. The levels of myeloperoxidase (MPO), interleukin (IL)- 6, TNF-α, IL-1ß and IL-18 in bronchoalveolar lavage fluid (BALF) were determined by ELISA. Western blotting was used to detect the expression of pyroptosis related proteins. The results showed that Ibrutinib treatment significantly improved the prognosis of mice and mitigated the lung histopathological injury and inflammatory response. Moreover, Ibrutinib significantly inhibited the expression of pyroptosis related proteins (NLRP3, Caspase-1, Gasdermin D (GSDMD), IL-1ß and IL-18) in the lung tissues of sepsis mice. In conclusion, our results suggest that Ibrutinib exerted protective effects against lung injury of septic mice and inhibited the activation of pyroptosis in lung tissue, which may be a potential treatment for sepsis induced lung injury.

Assessment of serum interleukin-28 as a biomarker to predict mortality in traumatic patients with sepsis.

BACKGROUND: Serious trauma due to various factors is a major global public issue, and sepsis is a major cause of trauma-associated mortality. Timely diagnosis and suitable treatment of post-traumatic sepsis are crucial to improve the hospital outcome of traumatic patients. IL-28 is a newly discovered member of IFN-λ family with multiple functions in inflammatory response. To date, its role in the pathogenic mechanisms of post-traumatic sepsis still remains unknown. METHODS: In total, 20 healthy controls, 55 traumatic patients without sepsis and 54 traumatic patients with sepsis were enrolled in this study. Serum IL-28A/B levels were investigated by ELISA. RESULTS: IL-28A/B levels were significantly increased in traumatic patients compared to healthy volunteers. Moreover, septic trauma patients displayed a significant increase in IL-28A/B levels compared with non-septic patients. In septic patients, IL-28A/B were negatively correlated with IFN-γ, IL-5, IL-13 and IL-17, and positively associated with IL-10. Moreover, IL-28A (AUC: 0.821, 95 %CI: 0.693-0.949) and IL-28B (AUC: 0.811, 95 %CI: 0.691-0.931) were both beneficial to predict increased mortality risk in septic trauma patients, though there was no statistical difference in the predictive value between them. CONCLUSIONS: Early serum levels of IL-28A/B were associated with the development of post-trauma sepsis and could be applied to assess the outcome of traumatic patients with sepsis. Thus, IL-28 may be a potential indicator for post-traumatic sepsis.

MMP-1 Over-expression Promotes Malignancy and Stem-Like Properties of Human Osteosarcoma MG-63 Cells In Vitro.

Osteosarcoma is the most common primary malignant bone tumor in childhood, and it maintains a high level of recurrence. Matrix metalloproteinase-1 (MMP-1) was found to contribute to cancer progression. The present study was to investigate the in vitro effects of MMP-1 over-expression on the proliferation, invasion, metastasis and stem-like properties of osteosarcoma MG-63 cells. The MG-63 cells were cultured and had a full length MMP-1 cDNA inserted by the lentiviral vector (MG-63MMP-1+). MG-63 negative control and MG-63 blank control groups were established as well. MMP-1 expression was detected in MG-63MMP-1+, MG-63 negative control and MG-63 blank control cells using qPCR, Western blotting and immunofluorescence after 24 h of culture. The cell proliferation assay was performed with a camera attached to a bioreactor, which was programmed to photograph five regions of each well every 10 min over a period of 48 h. The cell invasion assay was conducted with Matrigel to assess the invasive potential of MG-63 cells over 24 h, the qPCR analysis to measure stem cell markers, including Oct4, Sox-2, Nanog, and Pax-7, and Western blot analysis to detect invasive and metastatic potential markers TIMP-1, VEGF and BMP2/4, after 24 h of culture. Immunofluorescence was used to investigate the presence of the stem cell marker Pax-7 after 24-h culture. The results showed that over-expression of MMP-1 after transfection could significantly increase tumor cell proliferation and invasion (P<0.05, MG-63MMP-1+versus controls). Pax-7 was highly expressed in MG-63MMP-1+ cells, with no significant changes of Oct-4, Sox-2, and Nanog observed (P<0.05). MG-63MMP-1+ cells showed higher expression of VEGF and BMP 2/4 proteins and lower expression of TIMP-1 protein than controls (P<0.05). It was concluded that MMP-1 over-expression in MG-63 cells contributed to the proliferation, invasion, metastasis and stem-like properties of osteosarcoma cells. Future studies should focus on in vivo effects of MMP-1 over-expression and the application of MMP-1 and Pax-7 inhibition in vivo to osteosarcoma therapies.

Development of a sensitive and specific epitope-blocking ELISA for universal detection of antibodies to human enterovirus 71 strains.

BACKGROUND: Human Enterovirus 71 (EV71) is a common cause of hand, foot and mouth disease (HFMD) in young children. It is often associated with severe neurological diseases and mortalities in recent outbreaks across the Asia Pacific region. Currently, there is no efficient universal antibody test available to detect EV71 infections. METHODOLOGY/PRINCIPAL FINDING: In the present study, an epitope-blocking ELISA was developed to detect specific antibodies to human EV71 viruses in human or animal sera. The assay relies on a novel monoclonal antibody (Mab 1C6) that specifically binds to capsid proteins in whole EV71 viruses without any cross reaction to any EV71 capsid protein expressed alone. The sensitivity and specificity of the epitope-blocking ELISA for EV71 was evaluated and compared to microneutralization using immunized animal sera to multiple virus genotypes of EV71 and coxsackieviruses. Further, 200 serum sample from human individuals who were potentially infected with EV71 viruses were tested in both the blocking ELISA and microneutralization. Results indicated that antibodies to EV71 were readily detected in immunized animals or human sera by the epitope blocking ELISA whereas specimens with antibodies to other enteroviruses yielded negative results. This assay is not only simpler to perform but also shows higher sensitivity and specificity as compared to microneutralization. CONCLUSION: The epitope-blocking ELISA based on a unique Mab 1C6 provided highly sensitive and 100% specific detection of antibodies to human EV71 viruses in human sera.

[Acute toxicity of CCR5 antagonist C25P polypeptide in mice and its carcinogenicity in vitro].

OBJECTIVE: To study the acute toxicity of C25P polypeptide, a CCR5 antagonist, in mice and its carcinogenic effect in vitro. METHODS: The acute toxicity of C25P polypeptide in mice was assessed by determining the maximum tolerated dose (MTD). The mice were given C25P at the dose of 3.64 g/kg by tail vein injection, and the control mice received saline (40 ml/kg) injection. The mice were continuously observed for 14 days after the administration and sacrificed on day 14 for routine blood test, examination of the blood biochemistry and pathological examination. The carcinogenicity of C25P polypeptide in vitro was evaluated in cultured cell lines by chromosome aberration test, cell transformation test and non-anchorage dependent growth test. RESULTS: No mice died following administration of the drug, but 3 mice showed mild adverse reactions. The rats in both groups showed an increase in the body weight at a comparable rate. GPT increased and ALP decreased significantly in C25P polypeptide group (P<0.05). Most of the organs of the rats treated with in C25P polypeptide remained normal, but 3 mice showed pathologies in the lung, spleen and liver. Chromosome aberration test, cell transformation test and non-anchorage-dependent growth test all yielded negative results for C25P polypeptide. CONCLUSION: C25P polypeptide is a low-toxicity drug that produces no apparent acute toxicity in mice or obvious carcinogenicity in vitro.

Urokinase-type plasminogen activator receptor induces conformational changes in the integrin alphaMbeta2 headpiece and reorientation of its transmembrane domains.

The glycosylphosphatidylinositol-linked urokinase-type plasminogen activator receptor (uPAR) interacts with the heterodimer cell adhesion molecules integrins to modulate cell adhesion and migration. Devoid of a cytoplasmic domain, uPAR triggers intracellular signaling via its associated molecules that contain cytoplasmic domains. Interestingly, uPAR changes the ectodomain conformation of one of its partner molecules, integrin alpha(5)beta(1), and elicits cytoplasmic signaling. The separation or reorientation of integrin transmembrane domains and cytoplasmic tails are required for integrin outside-in signaling. However, there is a lack of direct evidence showing these conformational changes of an integrin that interacts with uPAR. In this investigation we used reporter monoclonal antibodies and fluorescence resonance energy transfer analyses to show conformational changes in the alpha(M)beta(2) headpiece and reorientation of its transmembrane domains when alpha(M)beta(2) interacts with uPAR.

Permissive transmembrane helix heterodimerization is required for the expression of a functional integrin.

The current paradigm is that integrin is activated via inside-out signalling when its cytoplasmic tails and TMs (transmembrane helices) are separated by specific cytosolic protein(s). Perturbations of the helical interface between the alpha- and beta-TMs of an integrin, as a result of mutations, affect its function. Previous studies have shown the requirement for specific pairing between integrin subunits by ectodomain-exchange analyses. It remains unknown whether permissive alpha/beta-TM pairing of an integrin is also required for pairing specificity and the expression of a functionally regulated receptor. We performed scanning replacement of integrin beta2-TM with a TM of other integrin beta-subunits. With the exception of beta4 substitution, others presented beta2-integrins with modified phenotypes, either in their expression or ligand-binding properties. Subsequently, we adopted alphaLbeta2 for follow-on experiments because its conformation and affinity-state transitions have been well defined as compared with other members of the beta2-integrins. Replacement of beta2- with beta3-TM generated a chimaeric alphaLbeta2 of an intermediate affinity that adhered to ICAM-1 (intercellular adhesion molecule 1) but not to ICAM-3 constitutively. Replacing alphaL-TM with alphaIIb-TM, forming a natural alphaIIb/beta3-TM pair, reversed the phenotype of the chimaera to that of wild-type alphaLbeta2. Interestingly, the replacement of alphaLbeta2- with beta3-TM showed neither an extended conformation nor the separation of its cytoplasmic tails, which are well-reported hallmarks of an activated alphaLbeta2, as determined by reporter mAb (monoclonal antibody) KIM127 reactivity and FRET (fluorescence resonance energy transfer) measurements respectively. Collectively, our results suggest that TM pairing specificity is required for the expression of a functionally regulated integrin.

Down-regulation of integrin alpha M beta 2 ligand-binding function by the urokinase-type plasminogen activator receptor.

The cell adhesion molecule integrin alphaMbeta2 associates with the urokinase-type plasminogen activator receptor (uPAR) on monocytes and neutrophils. uPAR also associates with members of the beta1 and beta3 integrins, and it modulates the ligand-binding function of these integrins. In this study, we showed that co-expressing uPAR with alphaMbeta2 in 293 transfectants down-regulated the ligand-binding capacity of alphaMbeta2 to denatured protein, fibrinogen, and intercellular adhesion molecule 1 (ICAM-1). Migration of transfectants on fibrinogen mediated by alphaMbeta2 was reduced in the presence of uPAR. In addition, the constitutive ligand-binding property of an alphaMbeta2 mutant was attenuated by its association with uPAR. Co-immunoprecipitation analyses using a panel of alphaMbeta2-specific mAbs suggest shielding of the ligand-recognition site of alphaMbeta2 by uPAR.