The diaphragm is one of the most important respiratory muscles in the human body,of which 60%-80%of the function of the respiratory muscle is played by the diaphragm.Mechanical ventilation is a common respiratory support method for severely ill patients in clinical.However,improper use of the ventilator can also lead to ventilator-induced diaphragm dysfunction(VIDD)while maintaining patients'respiratory function.The pathogenesis of VIDD is mainly induced by mechanical ventilation leading to diaphragmatic mitochondrial oxidative stress(MOS).In addition,the protein degradation of the ubiquitin-proteasome system(UPS),autophagy,changes in calpain activity,calcium,and cytokines also play important roles in the process of VIDD.In-depth understanding the pathological mechanism of VIDD is beneficial to prevent and treat VIDD.This article reviews the research progress of the potential etiology(improper use of ventilator,age,nutritional and metabolic status,coronary disease,drug factors)and pathogenesis(mitochondrial oxidative stress,autophagy of diaphragm cells,activation of calpain,and increase of intracellular calcium)of VIDD,so as to provide reference for the treatment of VIDD.

PEP06 is a novel endostatin-Arg-Gly-Asp-Arg-Gly-Asp(RGDRGD)30-amino-acid polypeptide featuring a terminally fused RGDRGD hexapeptide at the N terminus.The active endostatin fragment of PEPO6 directly targets tumor cells and exerts an antitumoral effect.However,little is known about the kinetics and degradation products of PEP06 in vitro or in vivo.In this study,we investigated the in vitro metabolic stability of PEP06 after it was incubated with living cells obtained from animals of different species;we further identified the degradation characteristics of its cleavage products.PEP06 underwent rapid enzymatic degradation in multiple types of living cells,and the liver,kidney,and blood play important roles in the metabolism and clearance of the peptides resulting from the molecular degradation of PEP06.We identified metabolites of PEP06 using full-scan mass spectrometry(MS)and tandem MS(MS2),wherein 43 metabolites were characterized and identified as the degradation metabolites from the parent peptide,formed by successive losses of amino acids.The metabolites were C and N terminal truncated products of PEP06.The structures of 11 metabolites(M6,M7,M16,M17,M21,M25,M33,M34,M39,M40,and M42)were further confirmed by comparing the retention times of similar full MS spectrum and MS2 spectrum information with reference standards for the synthesized metabolites.We have demonstrated the metabolic stability of PEP06 in vitro and identified a series of potentially bioactive downstream metabolites of PEP06,which can support further drug research.

Targeted gene therapy has become a promising approach for lung cancer treatment. In our previous work, we reported that the targeted expression of microRNA-7 (miR-7) operated by thyroid transcription factor-1 (TTF-1) promoter inhibited the growth of human lung cancer cells in vitro and in vivo; however, the intervention efficiency needed to be further improved. In this study, we identified the core promoter of TTF-1 (from -1299 bp to -871 bp) by 5' deletion assay and screened out the putative transcription factors nuclear factor-1 (NF-1) and activator protein-1 (AP-1). Further analysis revealed that the expression level of NF-1, but not AP-1, was positively connected with the activation of TTF-1 core promoter in human non-small-cell lung cancer (NSCLC) cells. Moreover, the silencing of NF-1 could reduce the expression level of miR-7 operated by TTF-1 core promoter. Of note, we optimized four distinct sequences to form additional NF-1-binding sites (TGGCA) in the sequence of TTF-1 core promoter (termed as ^optTTF-1 promoter), and verified the binding efficiency of NF-1 on the ^optTTF-1 promoter by electrophoretic mobility shift assay (EMSA). As expected, the ^optTTF-1 promoter could more effectively drive miR-7 expression and inhibit the growth of human NSCLC cells in vitro, accompanied by a reduced transduction of NADH dehydrogenase (ubiquinone) 1α subcomplex 4 (NDUFA4)/protein kinase B (Akt) pathway. Consistently, ^optTTF-1 promoter-driven miR-7 expression could also effectively abrogate the growth and metastasis of tumor cells in a murine xenograft model of human NSCLC. Finally, no significant changes were detected in the biological indicators or the histology of some important tissues and organs, including heart, liver, and spleen. On the whole, our study revealed that the optimized TTF-1 promoter could more effectively operate miR-7 to influence the growth of human NSCLC cells, providing a new basis for the development of microRNA-based targeting gene therapy against clinical lung cancer.
Animals ; Humans ; Mice ; Carcinoma, Non-Small-Cell Lung/therapy* ; Lung Neoplasms/metabolism* ; MicroRNAs/metabolism* ; Nuclear Proteins/metabolism* ; Thyroid Gland/pathology* ; Thyroid Nuclear Factor 1/genetics* ; Transcription Factors/metabolism*

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.
Adolescent ; Brain Abscess ; Child ; Child, Preschool ; Escherichia coli ; Female ; Humans ; Hydrocephalus ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial/epidemiology* ; Retrospective Studies ; Streptococcus agalactiae ; Streptococcus pneumoniae ; Subdural Effusion ; beta-Lactamases

Diagnosis, Differential ; Head ; Humans ; Immunoglobulin G ; Mikulicz' Disease/diagnosis* ; Submandibular Gland

OBJECTIVE Cerebral ischemia or ischemic stroke is due to insufficient blood supply to the brain, which causes hypoxia or ischemia in some areas. This work aimed to quantify the minerals and heavy metals in Qishiwei Zhenzhu pill in vivo and in vitro, analyze its effect on the types and abundance of intestinal flora, and study its mechanism on inflammation and apoptosis pathways as a treatment for cerebral ischemia. METHODS Microwave digestion and induc?tively coupled plasma mass spectrometry (ICP-MS) were used to determine the minerals and heavy metals in 10 batches of Qishiwei Zhenzhu pill in vitro. With the use of the middle cerebral artery obstruction (MCAO) model, ICP-MS was applied to determine the content of minerals and heavy metals in hepatic portal vein blood, abdominal aortic blood, brain, liver, kidney, hair, urine and feces at different time periods. On this model, the ileum, cecum, and colon tissues were tested for intestinal pathology, and 16S rRNA was used for sequencing. Species taxonomy, α diversity, and spe?cies microbial composition and structure analysis were also performed. Polymerase chain reaction and Western blotting were employed to determine the mRNA and protein expression of p38 MAPK, caspase-3, IL-1β and TNF-α in the isch?emic brain tissues of rats. RESULTS The average content of heavy metals in the 10 batches of Qishiwei Zhenzhu pill samples is in the descending order Hg>Cu>Pb. Significant differences in the metal elements are found among Qishiwei Zhenzhu pill from different manufacturers but not among the different batches of the same manufacturer. An extremely low content of heavy metals are absorbed into the blood or accumulated in the brain, liver, kidney, and other tissues. Stool is the main excretion route of minerals and heavy metals from Qishiwei Zhenzhu pill. This medicine helps repair the intestinal mucosa in MCAO rats. At the phylum level, it can regulate the abundance of Firmicutes and Proteobacteria in the intestinal flora of rats with cerebral ischemia. At the genus level, it can adjust the abundance of Escherichia Shigella. At the species level, it can adjust the abundance of Lactobacillus yoelii and Lactobacillus reuteri. Cluster classification results show that Qishiwei Zhenzhu pill can improve the intestinal flora of rats with cerebral ischemia, reduce the mRNA and protein expression of caspase-3 and IL-1βin rat brain tissues, and have a tendency to decrease the mRNA expres?sion of p38 MAPK and TNF-α. CONCLUSION Quantifying the minerals and heavy metals in Qishiwei Zhenzhu pill in vivo and in vitro will help improve their quality standards. Minerals and heavy metals are mainly excreted in feces, accumu?late in extremely low levels in various tissues, and do not damage the intestinal mucosa. The effective material basis of Qishiwei Zhenzhu pill in treating cerebral ischemia may be related to their Li, Cr, and Cd elements. These pills can improve the environment of intestinal flora, and their mechanism of treatment for cerebral ischemia may be related to the down-regulation of IL-1βinflammatory factor and inhibition of cell apoptosis.

OBJECTIVETo investigate the oxidative stress status and its effects on hepcidin in patients with hemoglobin H Constant Spring disease (HbH-CS).

METHODSA total of 35 patients were enrolled in the study, including 15 splenectomized cases and 20 non-splenectomized cases. 20 healthy volunteers were selected as controls. Serum superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), oxidized glutathione (GSSG) levels, erythropoietin (EPO), serum free transferrin receptor (sFTR), growth differentiation factor 15 (GDF15) as well as the level of hepcidin were detected. Correlation analysis and multiple factor regression analysis were performed to investigate the factors affecting the iron metabolism and erythropoiesis.

RESULTSCompared with healthy control, the SOD and GSH levels in patients with HbHCS decreased, while MDA and GSSG levels increased. The levels of SOD, MDA, GSG and GSSG were not significantly different between the patients with splenectomy and those without splenectomy. Correlation analysis showed that inpatients with HbHCS, EPO, sFTR and GDF15 correlated negatively with SOD level and positively with MDA level. EPO and sFTR levels negatively correlated with Hepcidin.

CONCLUSIONExcessive oxidative stress is present in patients with HbHCS, and hepcidin is inhibited by the upregulation of EPO and sFTR, and hence involved in iron overload in patients.

BACKGROUND: C-telopeptide and N-telopeptide cross-linked collagen type Ⅰ (CTx and NTx, respectively) are specific biochemical bone markers that can reflect bone formation and resorption. OBJECTIVE: To analyze the association of CTx with disuse osteoporosis. METHODS: Male Sprague-Dawley rats, weighing 180-220 g, were randomly divided into control and disuse osteoporosis groups. Right hind limbs of the rats in the disuse osteoporosis group were immobilitzed for 4 weeks by ankle-tail fixation to establish the rat model of disuse osteoporosis. Peritoneal venous blood was collected before and after modeling, and the femur was then removed to measure the serum CTx level and bone mineral density of the bilateral femurs. RESULTS AND CONCLUSION: The serum CTx level did not differ significantly between groups before modeling (P > 0.05). At 4 weeks after modeling, the serum CTx level in the disuse osteoporosis group was significantly higher than that in the control group and at baseline (P <0.01). The serum CTx level showed no significant change in the control group before and after modeling (P > 0.05). The increment of serum CTx in the disuse osteoporosis group exhibited a negative correlation with the bone mineral density of the bilateral femurs (r=0.426, P < 0.01). The bone mineral density of the right femur in the disuse osteoporosis group was significantly lower than that of the left one in the disuse osteoporosis group and the right one in the control group (P < 0.01), and there was no significant difference in the bone mineral density between left and right femurs in the control group (P > 0.05). These results imply that the model of disuse osteoporosis by ankle-tail fixation is established successfully. Disuse osteoporosis can promote the production of CTx further reducing bone mineral density; CTx is positively correlated with the degree of bone loss, so it can be used for therapeutic assessment and diagnosis of osteoporosis.

Aim To explore the mechanism of catechin in inhibiting Th2-driven inflammation responses of allergic asthma mice.Methods Female BALB/c mice were chosen to establish an allergic asthma model by sensitized and excited with OVA.Then,the administered group was intervened with catechin by series of dose (75,150,300 mg · kg-1).The proportion of peripheral leukocyte cells was analysed,and pathological changes in lung tissues were observed by HE dyeing.The levels of TSLP,IL-5,IL-13 in lung tissues and OVA specific IgE in mouse serum were measured using ELISA kit.NF-κB p65,IκB protein expression levels in lung tissues were investigated using Western blot,and NF-κB p65 nuclear translocation was detected with immunofluorescent technique.Results Catechin could not only effectively reduce the proportion of peripheral leukocyte cells,but relieve the levels of TSLP,Th2 inflammatory factor IL-5 and IL-13,and the activation of NF-κB signal pathway in lung tissues of allergic asthma mice.Conclusions Catechin can effectively relieve Th2 inflammation in allergic asthma mice induced by allergen OVA.The possible mechanism may be that it could reduce expression of TSLP by inhibiting the NF-κB signal.