The application value of metagenomic next-generation sequencing technology in the diagnosis and treatment of neonatal infectious meningitis - a single center retrospective case-control study.

OBJECTIVE: This retrospective study was conducted to investigate the application value of metagenomics next generation sequencing (mNGS) technology in the diagnosis and treatment of neonatal infectious meningitis. METHODS: From 1 January 2020 to 31 December 2022, 73 newborns suspected of infectious meningitis were hospitalized. After screening by inclusion and exclusion criteria, 69 newborns were subsequently included in the study, containing 27 cases with positive mNGS result and 42 cases with negative mNGS result. Furthermore, according to the diagnosis of meningitis, mNGS positive group and mNGS negative group were further divided into infectious meningitis with mNGS (+) group (n = 27) and infectious meningitis with mNGS (-) group (n = 26), respectively. RESULTS: (1) Compared with cerebrospinal fluid (CSF) culture, mNGS has better diagnostic value [positive predictive value (PPV) = 100.00% (27/27), negative predictive value (NPV) = 38.10% (16/42), agreement rate = 62.32% (43/69), area under the curve (AUC) = 0.750, 95% confidence interval (CI): 0.636-0.864]. (2) There were significant differences in the onset age, age at first CSF test, CSF leukocyte count, CSF glucose, positive rate of CSF culture, blood leukocyte count, procalcitonin (PCT), C-reaction protein (CRP), age at first mNGS test and adjusting anti-infective medication in the comparison between infectious meningitis with mNGS (+) group and infectious meningitis with mNGS (-) group (p < 0.05). (3) mNGS could help improve the cure rate [crude odds ratio (OR) = 3.393, 95%CI: 1.072-10.737; adjusted OR = 15.580, 95%CI: 2.114-114.798]. CONCLUSION: Compared with classic meningitis detection methods, mNGS has better PPV, NPV, agreement rate, and AUC. mNGS could help improve the cure rate.

Dose pulmonary hemorrhage increase the risk of bronchopulmonary dysplasia in very low birth weight infants?

OBJECTIVE: To evaluate the association between pulmonary hemorrhage and bronchopulmonary dysplasia (BPD) in very low birth weight infants (VLBWIs). METHODS: The study participants were all VLBW newborns admitted from January 1, 2019 to December 31, 2021. The BPD subjects finally included were VLBWIs who survived until the diagnosis was established. This study was divided into pulmonary hemorrhage group (PH group, n = 35) and non-pulmonary hemorrhage group (Non-PH group, n = 190). RESULTS: By univariate analysis it was found that premature rupture of membranes, tracheal intubation in the delivery room, duration of mechanical ventilation, course of invasive ventilation (≥3 courses), pulmonary surfactant (>1 dose), medically and surgically treated patent ductus arteriosus, grade III-IV RDS, early onset sepsis, BPD and moderate to severe BPD showed significant differences between groups (p < .05). By Multivariate analysis, pulmonary hemorrhage did not increase the risks of BPD and moderate to severe BPD (adjusted OR for BPD = 1.710, 95% CI 0.581-5.039; adjusted OR for moderate to severe BPD = 2.401, 95% CI 0.736-7.834). CONCLUSION: It suggests that pulmonary hemorrhage is not associated with the development of BPD and moderate to severe BPD in VLBWIs.

[Oxygen reserve index: a new parameter for oxygen therapy]. / 氧储备指数：氧疗监测的新方法.

Oxygen reserve index (ORI) is a novel dimensionless index used for noninvasive, real-time, and continuous monitoring of oxygenation, and ORI value ranges from 0 to 1, which reflects the range of 100-200 mmHg for arterial partial pressure of oxygen. ORI combined with pulse oximetry may help to accurately adjust the concentration of inspired oxygen and prevent hyperoxemia and hypoxemia. ORI is suitable for various clinical situations, and the medical staff should master this novel parameter and use it properly to assess the oxygenation of patients. In addition, several limitations of ORI should be noticed during clinical application.

[The role and mechanism of autophagy in lipopolysaccharide-induced inflammatory response of A549 cells]. / 自噬在脂多糖诱导的A549ç»†èƒžç‚Žç—‡ååº”ä¸­çš„ä½œç”¨åŠæœºåˆ¶ç ”ç©¶.

OBJECTIVES: To study the role and mechanism of autophagy in lipopolysaccharide (LPS)-induced inflammatory response of human alveolar epithelial A549 cells. METHODS: A549 cells were stimulated with LPS to establish a cell model of inflammatory response, and were then grouped (n=3 each) by concentration (0, 1, 5, and 10 µg/mL) and time (0, 4, 8, 12, and 24 hours). The A549 cells were treated with autophagy inhibitor 3-methyladenine (3-MA) to be divided into four groups (n=3 each): control, LPS, 3-MA, and 3-MA+LPS. The A549 cells were treated with autophagy agonist rapamycin (RAPA) to be divided into four groups (n=3 each): control, LPS, RAPA, and RAPA+LPS. The A549 cells were transfected with the Toll-like receptor 4 (TLR4) overexpression plasmid to be divided into four groups (n=3 each): TLR4 overexpression control, TLR4 overexpression, TLR4 overexpression control+LPS, and TLR4 overexpression+LPS. The A549 cells were transfected with TLR4 siRNA to be divided into four groups (n=3 each): TLR4 silencing control,TLR4 silencing, TLR4 silencing control+LPS, and TLR4 silencing+LPS. CCK-8 assay was used to measure cell viability. Western blot was used to measure the protein expression levels of inflammatory indicators (NLRP3, Caspase-1, and ASC), autophagic indicators (LC3B, Beclin-1, and P62), and TLR4. RESULTS: After stimulation with 1 µg/mL LPS for 12 hours, the levels of inflammatory indicators (NLRP3, Caspase-1, and ASC), autophagic indicators (LC3B, Beclin-1, and P62), and TLR4 increased and reached the peak (P<0.05). Compared with the LPS group, the 3-MA+LPS group had reduced expression of autophagy-related proteins and increased expression of inflammation-related proteins and TLR4, while the RAPA+LPS group had increased expression of autophagy-related proteins and reduced inflammation-related proteins and TLR4 (P<0.05). The TLR4 overexpression+LPS group had reduced autophagy-related proteins and increased inflammation-related proteins compared with the TLR4 overexpression control+LPS group, and the TLR4 silencing+LPS group had increased autophagy-related proteins and reduced inflammation-related proteins compared with the TLR4 silencing control+LPS group (P<0.05). CONCLUSIONS: In the LPS-induced inflammatory response of human alveolar epithelial A549 cells, autophagic flux has a certain protective effect on A549 cells. TLR4-mediated autophagic flux negatively regulates the LPS-induced inflammatory response of A549 cells.

[Sudden unexpected postnatal collapse in a neonate].

A healthy full-term female neonate, aged 3 days and born by vaginal delivery (with a 1-minute Apgar score of 10 and a 5-minute Apgar score of 10), had unexpected cardiac and respiratory arrests in the early morning on day 3 after birth and recovered to spontaneous breathing and heartbeat after a 10-minute resuscitation. The child had poor response and convulsion after resuscitation. Blood gas analysis showed metabolic acidosis, and amplitude-integrated EEG showed a burst-suppression pattern. She was diagnosed with sudden unexpected postnatal collapse but improved after hypothermia and symptomatic/supportive treatment. This article reports the first case of sudden unexpected postnatal collapse in China and summarizes related risk factors, pathophysiological mechanisms, and preventive and treatment measures of this disorder.

[Diagnostic values of prealbumin and retinol-binding protein for liver damage caused by different degrees of neonatal asphyxia].

OBJECTIVE: To investigate the diagnostic values of prealbumin (PAB) and retinol-binding protein (RBP) for liver damage caused by mild or severe asphyxia. METHODS: A retrospective analysis was performed on 185 neonates (including 84 premature infants and 101 full-term infants) with asphyxia. Based on the Apgar score, they were divided into two groups: mild asphyxia group (n=150) and severe asphyxia group (n=35). The levels of PAB, RBP, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were measured and compared. Their diagnostic values for liver damage were evaluated by ROC curve analysis. RESULTS: The premature infants in the severe asphyxia group had significantly higher AST level and significantly lower levels of PAB and RBP than those in the mild asphyxia group (P<0.05). The full-term infants in the severe asphyxia group had a significantly lower PAB level than those in the mild asphyxia group (P<0.05). After treatment, the PAB level was significantly improved in the premature infants in the severe asphyxia group and in the full-term infants in both mild and severe asphyxia group (P<0.05). The full-term infants in the mild asphyxia groups also showed a significant improvement in AST level (P<0.05). The ROC curve analysis showed that PAB had a good sensitivity and specificity for identifying liver damage caused by mild or severe asphyxia in full-term and preterm infants. CONCLUSIONS: PAB can be used as an indicator of liver damage caused by asphyxia in neonates, and can be used to assess the degree of asphyxia.