[Status of fungal sepsis among preterm infants in 25 neonatal intensive care units of tertiary hospitals in China].

Objective: To analyze the prevalence and the risk factors of fungal sepsis in 25 neonatal intensive care units (NICU) among preterm infants in China, and to provide a basis for preventive strategies of fungal sepsis. Methods: This was a second-analysis of the data from the "reduction of infection in neonatal intensive care units using the evidence-based practice for improving quality" study. The current status of fungal sepsis of the 24 731 preterm infants with the gestational age of <34+0 weeks, who were admitted to 25 participating NICU within 7 days of birth between May 2015 and April 2018 were retrospectively analyzed. These preterm infants were divided into the fungal sepsis group and the without fungal sepsis group according to whether they developed fungal sepsis to analyze the incidences and the microbiology of fungal sepsis. Chi-square test was used to compare the incidences of fungal sepsis in preterm infants with different gestational ages and birth weights and in different NICU. Multivariate Logistic regression analysis was used to study the outcomes of preterm infants with fungal sepsis, which were further compared with those of preterm infants without fungal sepsis. The 144 preterm infants in the fungal sepsis group were matched with 288 preterm infants in the non-fungal sepsis group by propensity score-matched method. Univariate and multivariate Logistic regression analysis were used to analyze the risk factors of fungal sepsis. Results: In all, 166 (0.7%) of the 24 731 preterm infants developed fungal sepsis, with the gestational age of (29.7±2.0) weeks and the birth weight of (1 300±293) g. The incidence of fungal sepsis increased with decreasing gestational age and birth weight (both P<0.001). The preterm infants with gestational age of <32 weeks accounted for 87.3% (145/166). The incidence of fungal sepsis was 1.0% (117/11 438) in very preterm infants and 2.0% (28/1 401) in extremely preterm infants, and was 1.3% (103/8 060) in very low birth weight infants and 1.7% (21/1 211) in extremely low birth weight infants, respectively. There was no fungal sepsis in 3 NICU, and the incidences in the other 22 NICU ranged from 0.7% (10/1 397) to 2.9% (21/724), with significant statistical difference (P<0.001). The pathogens were mainly Candida (150/166, 90.4%), including 59 cases of Candida albicans and 91 cases of non-Candida albicans, of which Candida parapsilosis was the most common (41 cases). Fungal sepsis was independently associated with increased risk of moderate to severe bronchopulmonary dysplasia (BPD) (adjusted OR 1.52, 95%CI 1.04-2.22, P=0.030) and severe retinopathy of prematurity (ROP) (adjusted OR 2.55, 95%CI 1.12-5.80, P=0.025). Previous broad spectrum antibiotics exposure (adjusted OR=2.50, 95%CI 1.50-4.17, P<0.001), prolonged use of central line (adjusted OR=1.05, 95%CI 1.03-1.08, P<0.001) and previous total parenteral nutrition (TPN) duration (adjusted OR=1.04, 95%CI 1.02-1.06, P<0.001) were all independently associated with increasing risk of fungal sepsis. Conclusions: Candida albicans and Candida parapsilosis are the main pathogens of fungal sepsis among preterm infants in Chinese NICU. Preterm infants with fungal sepsis are at increased risk of moderate to severe BPD and severe ROP. Previous broad spectrum antibiotics exposure, prolonged use of central line and prolonged duration of TPN will increase the risk of fungal sepsis. Ongoing initiatives are needed to reduce fungal sepsis based on these risk factors.

Interrupting TGF-ß1/CCN2/integrin-α5ß1 signaling alleviates high mechanical-stress caused chondrocyte fibrosis.

OBJECTIVE: Mechanical-stress has been reported to trigger cartilage fibrosis, in which transforming growth factor (TGF)-ß and connective tissue growth factor (CCN2) are involved. However, the function of integrin-α5ß1, a cytomembrane receptor, on mechanical-stress related fibrosis has not yet been elucidated. This study aims to reveal the interaction of TGF-ß1/CCN2/integrin-α5ß1 in the mechanical-stress induced chondrocyte (CH) fibrosis. PATIENTS AND METHODS: We used different levels (5% and 10%) of cyclic tension simulation (CTS) to stretch CHs and observed the gene expression of TGF-ß1/CCN2/integrin-α5ß1 as well as the fibrous related genes containing collagen I/II/III, Runx2, MMP13, and ADAMTS-5 by real-time polymerase chain reaction (RT-PCR) or immunofluorescence. We used the siRNA or the corresponding antagonist of TGF-ß1, CCN2, integrin-α5ß1 during the CTS to clear the effect of them in the fibrosis progress. In addition, to verify the crosstalk between TGF-ß1, CCN2, and integrin-α5ß1, we used the recombinant human (rh)-TGF-ß1 and CCN2 to culture CHs without CST. RESULTS: 24 hours-10% CTS was sufficient to induce a decrease of collagen II and increase the collagen I/III, Runx2, MMP13, and ADAMTS-5 gene expression. Under CTS, TGF-ß1 silencing resulted in a decline of CCN2, integrin-α5ß1, and alleviated the CHs fibrosis. Apart from this, blocking CCN2 or integrin-α5ß1 expression also contributed to the suppression of 10% CTS induced CHs fibrosis. Meanwhile, the exogenic protein supplement raised the cellular TGF-ß1 or CCN2 expression and increased the integrin-α5ß1 mRNA level. However, the downregulation of TGF-ß1 or CCN2 did not affect integrin-α5ß1 expression, whether the CTS exited or not. CONCLUSIONS: High mechanical-stress induces CHs fibrosis via the activation of TGF-ß1/CCN2/integrin-α5ß1 signaling, and interrupting the TGF-ß1, CCN2, or integrin-α5ß1 expression can alleviate the fibrous process.

RBM5-AS1 participates in fracture healing and inhibits apoptosis of bone cells through the up-regulation of ß-catenin.

OBJECTIVE: The aim of this study was to detect the expression of RBM5-AS1 during fracture healing, and to explore its possible mechanism. MATERIALS AND METHODS: A mice tibia fracture model was constructed in this study. Mice in the control group and experimental group were sham-operated on the left tibia and were operated in the right tibia, respectively. The tibia bones of both groups were obtained at 4 d, 8 d, 12 d, 16 d, 20 d, and 24 d after the operation. Quantitative polymerase chain reaction (qPCR) was used to detect the expression of RBM5-AS1 in tibiae. After interfering with the expression of RBM5-AS1 in bone cells, Cell Counting Kit-8 (CCK-8) was used to detect cell proliferation ability, and flow cytometry was applied to detect apoptosis. Western blot was used to measure the protein expression of beta-catenin and RBM5 after down-regulating RBM5-AS1. Finally, beta-catenin was interfered in osteoblasts to explore the relationship between RBM5-AS1 and beta-catenin. RESULTS: Compared with the control group, the expression of RBM5-AS1 in the experimental group was significantly increased on the 4 d, 8 d, 12 d, and 16 d after fracture surgery. However, no statistical difference was observed on the 20 d and 24 d between the two groups. After interfering with RBM5-AS1, the apoptosis of chondrocytes and osteoblasts was significantly increased in both mouse and human cells, while the expression of beta-catenin was strikingly decreased. Further up-regulation of beta-catenin could reduce the apoptosis of bone cells. The expression of RBM5, which was a natural antisense transcript of RBM5-AS1, was increased after down-regulating RBM5-AS1. CONCLUSIONS: RBM5-AS1 can inhibit the apoptosis of bone cells by promoting the expression of beta-catenin and can be used as a biomarker for fracture healing.

Impaired learning and memory in rats induced by a high-fat diet: Involvement with the imbalance of nesfatin-1 abundance and copine 6 expression.

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease, resulting not only in liver dysfunction, glucose and lipid metabolism disorder, but also in neuropsychiatric damage. In the present study, a NAFLD rat model was established via feeding of a high-fat diet, and behaviour was observed via the open field test (OFT), the sucrose preference test (SPT), the elevated plus maze (EPM), the forced swimming test (FST) and the Morris water maze (MWM). The plasma concentrations of alanine aminotransferase (ALT), glucose, free fatty acid (FFA), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were detected using chemiluminescence technique. The plasma levels of nesfatin-1, leptin and insulin were measured via enzyme-linked immunosorbent assay, and the protein expressions of p-glycogen synthase kinase-3ß (GSK-3ß), GSK-3ß, p-ß-catenin, ß-catenin, cyclinD and copine 6 in the hippocampus and prefrontal cortex (PFC) were detected using western blotting. After 4 consecutive weeks of feeding with a high-fat diet, the rats showed obesity; increased plasma concentrations of ALT, glucose, FFA, TC, TG, HDL-C and LDL-C; decreased plasma levels of leptin and insulin; and inflammation and mild hepatocyte steatosis in the liver. Although there was no significant difference between groups with regard to performance in the OFT, EPM or FST, the NAFLD rats showed a decreased sucrose preference index in the SPT and impaired learning and memory in the MWM task. Moreover, the present study provides the first evidence of an increased plasma nesfatin-1 concentration in NAFLD rats, which was significantly correlated with plasma lipid concentrations and behavioural performance. Furthermore, copine 6 and p-ß-catenin protein expression decreased and p-GSK-3ß increased in the hippocampus and PFC of NAFLD rats. These results suggest that consuming of a high-fat diet for 4 consecutive weeks could successfully induce a NAFLD rat model. More importantly, these results provide the first evidence that impaired learning and memory in NAFLD rats was, at least partly, associated with increased plasma nesfatin-1 concentration and decreased copine 6 expression in the hippocampus and PFC.

Sex differences in ICR mice in the Morris water maze task.

The Morris water maze (MWM) is one of the most common tasks used to assess spatial learning and memory ability in rodents. Genetic strain and gender are two prominent variants that influence spatial performance. Although it was reported that ICR (Institute of Cancer Research) mice exhibited an unchanged baseline performance in the training phase of the MWM task, this outbred strain has been widely used in learning and memory studies, and little is known regarding the effects of sex on behavioral performance. In this study, we demonstrated that both male and female ICR mice could complete the MWM task. Furthermore, a significant sex difference was observed, with females having shorter escape latencies and longer durations in the target quadrant in both the acquisition and test phases. Our findings emphasize the necessity of careful examination of not only the strain effect on behavioral performance but also the sex effect.

Impaired learning and memory performance in a subclinical hypothyroidism rat model induced by hemi-thyroid electrocauterisation.

It is well known that clinical hypothyroidism (CH) can induce cognitive deficits, and the decision to start treatment for CH with thyroxine is usually straightforward. However, the relationship of cognition dysfunction with subclinical hypothyroidism (SCH) is inconsistent, and the decision concerning the need to treat SCH is controversial. In the present study, we induced a SCH rat model by hemi-thyroid electrocauterisation; then employed a serial of behavioural tests, including a beam balance, open field task and Morris water maze (MWM), to investigate the behaviour performance of SCH rats; and finally explored the protein expression of phosphorylated extracellular signal-regulated kinase (ERK)1/2 in the hippocampus by western blotting. The results demonstrated that hemi-thyroid electrocauterised rats had an elevated plasma thyrotrophin-stimulating hormone (TSH) level, with normal free thyroxine (fT4) and triiodothyronine (T3) concentrations, which defines SCH in humans. If rat SCH is diagnosed according to measurements of both plasma TSH higher than 97.5 percentile for the sham group and fT4 in the range 2.5-97.5 percentile for the sham group, the success rate of SCH modelling was 66.6%. SCH decreased exploratory behaviour but did not affect motor function in rats, showing a negative correlation of exploratory behaviour with plasma TSH concentration. Moreover, SCH rats displayed an impairment of learning and memory ability in the MWM task, with a longer escape latency in the acquisition phase and a shorter duration in the target quadrant in the test phase compared to that of sham rats. The mechanism for this might be related to the increased plasma TSH concentration, the decreased hippocampal T3 level and the enhanced expression of phosphorylated ERK1/2 in the hippocampus. The results of the present study, together with the results obtained in other studies, suggest that treatment is necessary for SCH.