BACKGROUND:Congenital hypothyroidism (CH) is a common condition in both preterm and term infants characterized by either thyroid gland absence or hypofunctionality. The clinical association of refractory lactic acidosis and heart failure has rarely been observed in cases of pediatric patients with CH pathology. Here, we explored the etiological relationship between CH, heart failure, and refractory lactic acidosis to reflect the importance of thyroid function screening in neonates with heart disease. CASE SUMMARY:A 33-day-old extremely premature female infant presented with tachypnea, respiratory distress, recurrent infections, and abdominal distension postnatal. On admission to our facility, she had cardiomegaly, hepatomegaly, and lactic acidosis (revealed on blood gas analysis), with lactate progressively rising to 25 mmol/L. Chest radiographs showed pulmonary congestion, while echocardiography revealed cardiac enlargement, left ventricular wall thickening, and pericardial effusion. Initial management aimed at correcting acidosis and treating heart failure proved ineffective. After reassessment, thyroid function tests showed significantly decreased triiodothyronine, free triiodothyronine, thyroxine, and free thyroxine levels, with a significantly increased thyroid-stimulating hormone level, confirming a CH diagnosis. Levothyroxine was administered, resulting in rapid correction of lactic acidosis and gradual improvement of thyroid function and systemic symptoms, culminating in full recovery and discharge. We also reviewed the relevant literature on thyroid and cardiac dysfunctions in order to explore their deeper association. CONCLUSION:This case links CH-induced heart failure with refractory lactic acidosis, urging prompt thyroid screening in affected neonates to reduce mortality.

Objective: To investigate how the high-altitude environment modifies severe pertussis in young infants and analyze its pathophysiological mechanisms and clinical management implications. Methods: Clinical data of two young infants with severe pertussis residing at 3650 m were retrospectively analyzed, including presentation, laboratory findings, pathogen detection, treatment, and outcomes. A literature review explored synergistic interactions between high-altitude factors and pertussis pathophysiology. Results: Case 1 had macrolide-resistant Bordetella pertussis (MRBP, 23S rRNA A2047G) with peak WBC 52.25 × 109/L, and received cefoperazone-sulbactam, piperacillin-tazobactam and azithromycin, and was successfully treated with trimethoprim-sulfamethoxazole combined with exchange transfusion. Case 2 had Bordetella pertussis confirmed by PCR with peak WBC 36.55 × 109/L, receiving cefoperazone-sulbactam and azithromycin, and recovered. Both developed respiratory failure requiring non-invasive ventilation and survived without pulmonary hypertension. High-altitude stressors—hypoxia, enhanced pulmonary vascular reactivity, and hypercoagulability—synergize with pertussis-induced hyperleukocytosis as a “dual hit,” accelerating cardiopulmonary deterioration and elevating thrombotic risks. Conclusions: High altitude is an independent risk modifier in infantile pertussis, demanding heightened vigilance and proactive interventions: early non-invasive ventilation, prophylactic anticoagulation, and timely exchange transfusion before pulmonary hypertension develops. This is the first high-altitude case series that provides essential insights for clinicians in similar environments globally, guiding early recognition and proactive management strategies to improve outcomes in this vulnerable population.

Telomerase reverse transcriptase (TERT) exhibits non-canonical neuroprotective functions; its overexpression protects against hypoxic-ischemic brain injury and preserves mitochondrial function. Here, we identified a novel phenomenon in an in vitro model in which oxygen-glucose deprivation/reoxygenation induced a phase-dependent redistribution of endogenous TERT in HT22 neuronal cells, characterized by early mitochondrial accumulation followed by predominant nuclear localization. We aimed to determine whether subcellular localization of TERT dictates its functional specificity in regulating the copy number of mitochondrial DNA-encoded genes in neurons. HT22 cells expressing TERT, targeted to either the mitochondria (mito-TERT) or nucleus (nuc-TERT), were generated using adenoviral transfection. Subcellular localization was confirmed using western blotting. Mitochondrial DNA copy number was assessed using quantitative polymerase chain reaction (qPCR), and direct mito-TERT binding was assessed using chromatin immunoprecipitation (ChIP)-qPCR; ND1 and ND2 mRNA levels were measured using qRT-PCR. Both nuc-TERT and mito-TERT models were successfully established. qPCR analysis showed that mito-TERT specifically upregulated the copy number of mitochondrial complex I genes (nicotinamide adenine dinucleotide-hydrogen dehydrogenase subunit [ND]1/2), whereas nuc-TERT broadly upregulated genes across complexes I, III, IV, and V. A regulation specificity index showed that mito-TERT selectively enhanced ND1 copy number. ChIP-qPCR confirmed mito-TERT enrichment at the ND1 and ND2 promoters. Together, these findings demonstrate that TERT regulates mitochondrial DNA copy number through distinct, compartment-dependent mechanisms. Mito-TERT exhibited gene-specific regulation via direct promoter binding, whereas nuc-TERT displayed broader effects. The stress-induced redistribution of TERT and these mechanistic insights reveal a novel paradigm for multiphasic TERT-mediated neuroprotection in brain injury.

BackgroundReducing under-5 mortality remains a global health priority. Large language models (LLMs) are increasingly used by the public to access medical information. However, current evidence evaluating LLMs’ performance in public-facing child health communication is scarce.MethodsWe selected the top five search terms related to each of the five leading causes of under-5 mortality (prematurity, pneumonia, birth asphyxia, malaria, and diarrhoea) using Google Trends, generating 25 representative public queries. Responses were collected from four LLMs (ChatGPT-4.0, Claude 3.5 Sonnet, Bing AI, and Gemini) and independently evaluated by four pediatricians. We used the DISCERN instrument for information reliability; 5-point Likert scales for accuracy, completeness, and comprehensibility; Flesch Reading Ease (FRE) and Flesch–Kincaid Grade Level (FKGL) indices for readability; and the Patient Education Materials Assessment Tool for Printable Materials (PEMAT-P) for understandability and actionability. Differences among models were evaluated with Kruskal–Wallis and ANOVA tests, with statistical significance set at p < 0.05.ResultsWe found significant performance variations among the four models across most evaluation metrics. Bing AI achieved the highest total DISCERN score (median 42) and the highest reliability subscore (Section A median 28). Claude consistently underperformed across multiple domains. Notably, readability was poor for all models, with high language complexity (mean FKGL score 12.4). Critically, actionability scores were near zero for all models on the PEMAT-P scale, reflecting a universal lack of clear and practical behavioral guidance.ConclusionWhile LLMs can generally provide accurate health information, limitations in readability and actionability restrict their practical application in public health communication. Future development should prioritize language simplification and clearer behavioral guidance to enhance their value in public-facing child health communication.

ETHNOPHARMACOLOGICAL RELEVANCE:Astragalus membranaceus is one of the most widely applied traditional Chinese herbal medicines. TA-65 is an extract of Astragalus membranaceus; however, the protective effects of TA-65 in brain damage during development remain unclear. AIM OF THE STUDY:To investigate the neuroprotective effects of TA-65 in a neonatal hypoxic-ischemic brain damage (HIBD) mouse model, focusing on the role of telomerase reverse transcriptase (TERT). MATERIALS AND METHODS:In vivo and in vitro HIBD models were established and treated with TA-65. Nuclear and mitochondrial TERT expressions were measured by western blotting and immunofluorescence. Brain injury was evaluated through the measurement of brain infarction areas and neuronal apoptosis. The neurological function of mice was assessed. TA-65 safety was evaluated by measuring mouse body weight, random blood glucose level, blood cell count, liver and kidney function, and immune function, as well as detecting tumor occurrence in vital organs. RESULTS:TA-65 administration upregulated mitochondrial TERT expression after HIBD both in vivo and in vitro, but did not influence nuclear TERT expression. TA-65 reduced neuronal apoptosis and brain infarction areas, and improved neurological function in mice after HIBD. TA-65 did not change telomere length in the brain or affect body weight, random blood glucose levels, blood cell counts, liver and kidney function, or immune function in mice after HIBD. TA-65 administration did not cause tumor occurrence in the vital organs of mice. CONCLUSIONS:TA-65 exerts neuroprotective effects in neonatal HIBD without significant side effects or tumorigenicity. The possible mechanism may involve enhanced mitochondrial TERT expression.

Breastmilk stem cells (BSCs) have been reported to have potential benefits for infants. However, whether the BSCs could improve brain injury is unknown. A culture system for BSCs was established, and the roles of BSCs in treating white matter injury (WMI) were investigated in our study. Breastmilk samples were collected from healthy lactating women between days 1 and 5 after delivery. The BSCs were cultured in a specialized culture medium and then characterized through flow cytometry and immunofluorescence methods. A rat model with WMI was established by ligating the right carotid artery of Sprague–Dawley rats at postnatal day 3 (P3) and exposing the rats to 6

OBJECTIVES:This study aimed to assess the need for adding heparin to parenteral nutrition (PN) on reducing catheter intraluminal obstruction based on scanning electron microscopy (SEM) of peripherally inserted central catheter (PICC) in preterm neonates. METHODS:In this randomized controlled blinded non-inferiority trial, neonates with gestational age <32 weeks requiring PICC to receive PN were enrolled and randomly divided into two groups. In the heparin group, 0.5 IU/mL heparin was added to PN for continuous infusion through PICC; while in the no-heparin group, there was no heparin added. All catheter tips were collected for SEM of catheter intraluminal obstruction. The primary outcome was the ratio of intraluminal obstructed area at catheter tip calculated by SEM. A non-inferiority margin of 0.1 was chosen. The duration of catheter patency, incidence of catheter-related complications, and heparin-related side effects were analyzed. RESULTS:Between June 1, 2021, and May 31, 2022, 91 neonates (gestational age of 28.17 ± 1.77 weeks) were ultimately enrolled. In the intention-to-treat analysis, the average ratio of intraluminal obstructed area at catheter tip indicated by SEM in no-heparin group was 0.313, and 0.362 in the heparin group (95% confidence intervals of the differences was -0.028 to 0.147). The lower bound of the one-side 95% confidence intervals was greater than -0.1, indicating non-inferiority. No statistically significant differences existed in the duration of catheter patency, the incidence of catheter-related complications between two groups. CONCLUSIONS:PN without heparin was non-inferior to the addition of 0.5 IU/mL heparin to PN during infusion on reducing catheter intraluminal obstruction based on SEM of PICC in preterm neonates. These findings could reduce the unnecessary exposure to heparin in preterm neonates.

Background This systematic review and meta-analysis aims to explore the potential impact of the route of administration on the efficacy of therapies and occurrence of adverse events when administering medications to premature infants with patent ductus arteriosus (PDA). Method The protocol for this review has been registered with PROSPERO (CRD 42022324598). We searched relevant studies in PubMed, Embase, Cochrane, and the Web of Science databases from March 26, 1996, to January 31, 2022. Results A total of six randomized controlled trials (RCTs) and five observational studies were included for analysis, involving 630 premature neonates in total. Among these infants, 480 were in the ibuprofen group (oral vs. intravenous routes), 78 in the paracetamol group (oral vs. intravenous routes), and 72 in the ibuprofen group (rectal vs. oral routes). Our meta-analysis revealed a significant difference in the rate of PDA closure between the the initial course of oral ibuprofen and intravenous ibuprofen groups (relative risk (RR) = 1.27, 95% confidence interval (CI) [1.13–1.44]; P < 0.0001, I2 = 0%). In contrast, the meta-analysis of paracetamol administration via oral versus intravenous routes showed no significant difference in PDA closure rates (RR = 0.86, 95% CI [0.38–1.91]; P = 0.71, I2 = 76%). However, there was no statistically significant difference in the risk of adverse events or the need for surgical intervention among various drug administration methods after the complete course of drug therapy. Conclusion This meta-analysis evaluated the safety and effectiveness of different medication routes for treating PDA in premature infants. Our analysis results revealed that compared with intravenous administration, oral ibuprofen may offer certain advantages in closing PDA without increasing the risk of adverse events. Conversely, the use of paracetamol demonstrated no significant difference in PDA closure and the risk of adverse events between oral and intravenous administration.

OBJECTIVES:To compare the efficacy and safety of different vasodilators in the treatment of persistent pulmonary hypertension of the newborn (PPHN) by a Bayesian network meta-analysis. METHODS:We searched databases (Cochrane, PubMed, Embase, and Web of Science) from January, 1990 up to December, 2023. Randomized controlled trials on the use of vasodilators in the treatment of PPHN. We extracted details of population, intervention, and outcome indicators. R and STATA software were used for data analysis. Sixteen articles were included, encompassing 776 neonates with PPHN. Among them, 12 articles were included in the quantitative analysis. The vasodilators included Sildenafil, Bosentan, Milrinone, Magnesium, Adenosine, and Tadalafil. RESULTS:The Bayesian network meta-analysis results suggested that compared to placebo, Milrinone [OR = 0.125, 95% CI (0.0261, 0.562)], Sildenafil [OR = 0.144, 95% CI (0.0428, 0.420)], and Sildenafil_Milrinone [OR = 0.0575, 95% CI (0.00736, 0.364)] reduced the mortality, but the difference among the three was not significant. There was also no significant difference in the incidence of hypotension, the duration of mechanical ventilation, and the use of extracorporeal membrane oxygenation among the vasodilators. Compared to Bosentan, Adenosine was more effective in reducing the oxygenation index [MD = -12.78, 95% CI (-25.56, -0.03)], and Magnesium was less effective in reducing the oxygenation index than Sildenafil [MD = 5.19, 95% CI (1.23, 9.2)]. CONCLUSIONS:Milrinone, Sildenafil, and Sildenafil_Milrinone reduced the mortality of neonates with PPHN. More clinical trials are needed to verify the efficacy and safety of vasodilators in the treatment of PPHN.

To the Editor: Unstable clinical conditions and complications make multiple laboratory tests and blood sampling inevitable in preterm infants, contributing to iatrogenic blood loss. Undoubtedly, iatrogenic blood loss is highly correlated with red blood cell transfusion (RBCT). A previous study on extremely low birth weight (BW) infants reported that the sampling blood loss was 30.0 mL/kg within the first week of life, leading to one or more RBCTs in 98% of patients.[1] RBCTs are increasingly reported to cause inflammatory responses and increase the incidence of preterm complications. Therefore, reducing iatrogenic blood loss could not only decrease the need for transfusions but also reduce the risk of neonatal mortality and morbidity. However, clinicians are not sufficiently aware of the risks of frequent sampling. Few studies reported detailed information on sampling blood loss of premature infants during hospitalization and its correlation with gestational age (GA) in preterm infants. Existing measures to reduce sampling blood loss, including staff education, smaller sampling vessels, closed blood sampling devices, and point-of-care testing, have been applied to adults and children in intensive care units (ICUs).[2] However, these measures have not been widely implemented in neonatal ICUs (NICUs). Therefore, we conducted a prospective cohort study on the quality management of blood sampling with historical controls, to evaluate sampling blood loss during hospitalization and clarify whether blood sampling management is beneficial for reducing RBCT in preterm infants. Infants with a GA < 32 weeks in the NICU of our institution were enrolled. All patients were admitted to the hospital within 24 h after birth. Neonates with cyanotic congenital heart disease, genetic and metabolic diseases, severe congenital malformations, treatment discontinuation, or lacking complete clinical data were excluded, as well as newborns who died or were transferred within 14 days of hospitalization. This study protocol was reviewed and approved by the Ethics Committee of West China Second Hospital of Sichuan University, approval number [2021088]. All study subjects had signed informed consent. We carried out blood sampling management according to the steps of the Quality Control Circle. In addition, based on the current investigation, the following measures were implemented: (1) educational intervention for the medical staff, such as requiring attending physicians to master the indications of each sampling test and sampling technology training for nursing personnel; (2) starting a standardized sampling table and strictly controlling each sampling volume defined by the minimum volume for each test; (3) sampling from the umbilical cord at birth for partial examinations; (4) using micro-blood sampling technology and bedside biochemical tests; and (5) using one sample for multiple tests. The sampling and RBCT volumes were expressed in mL/kg of the BW. All data analyses were descriptive and conducted using Excel (IBM, Inc., Chicago, IL, USA) and SPSS v24.0 (SPSS, Inc., Chicago, Illinois, USA). A P value of 0.05 was used to determine the statistical significance. The estimated sample size was 328 cases by using PASS 2021 software (NCSS, Kaysville, USA). Linear regression assessed the relationship between the sampling blood loss and cumulative RBCT volumes. In addition, we conducted a binary logistic regression analysis to explore the effect of sampling blood loss and the number of RBCTs on preterm complications, such as necrotizing enterocolitis (NEC), retinopathy of prematurity (ROP), and intra-ventricular hemorrhage (IVH). A total of 560 preterm infants were enrolled in this study: 284 infants in the group before sampling management and 276 infants in the group after blood collection management. The clinical characteristics were similar before and after sampling management [Supplementary Table 1, https://links.lww.com/CM9/B429]. The mortality rate was also similar between the two groups (before:1.1% [3/284]; after: 0.7% [2/276]). After starting sampling management, the number of samples and sampling blood loss volume were considerably reduced. The total sampling blood loss decreased by 35.3 mL/kg (before: 17.0 mL/kg; after 11.0 mL/kg; P < 0.001) in infants with a GA of ≥28 and <32 weeks and by 38.6 mL/kg (before: 53.9 mL/kg; after: 33.1 mL/kg; P < 0.001) in infants with a GA of <28 weeks[Table 1]. Table 1 - Change in blood sampling and RBCTs among very preterm infants before and after blood sampling management. Blood sampling RBCT GA∗ Vairables Before management (n = 284) After management (n = 276) Z P value Before management (n = 284) After management (n = 276) Z/χ 2 P value 28–32 Times On average during hospitalization 23 (14–31) 12 (9–22) −7.134 <0.001 0 (0–2) 0 (0–1) −1.553 0.120 On the first day 2 (2–3) 2 (1–2) −6.909 <0.001 – – Within 7 days 9 (7–11) 6 (4–7) −9.959 <0.001 38 (15.4) 19 (8.1) 6.319 0.012 Within 28 days 18 (13–25) 11 (8–17) −8.537 <0.001 103 (41.9) 80 (33.9) 3.250 0.071 Volume (mL/kg) Total 17.0 (9.7–27.0) 11.0 (7.1–22.0) −4.061 <0.001 0 (0–41.7) 0 (0–30.7) −1.384 0.167 On the first day 2.8 (2.0–4.0) 1.9 (1.4–2.6) −7.334 <0.001 – – Within 7 days 6.4 (4.3–9.6) 4.6 (3.1–6.9) −5.415 <0.001 0 (0–0) 0 (0–0) −2.373 0.018 Within 28 days 14.0 (8.4–23.0) 9.5 (6.6–18.0) −4.817 <0.001 0 (0–24.1) 0 (0–23.1) −1.360 0.174 <28 Times On average during hospitaliztion 58 (42–71) 27 (19–35) −6.020 <0.001 3.6 ± 2.3 2.4 ± 1.6 −2.238 0.025 On the first day 2 (2–3) 2 (2–2) −1.946 0.052 – – Within 7 days 12 (9–14) 7 (5–9) −5.904 <0.001 16 (42.1) 13 (32.5) 0.770 0.380 Within 28 days 32 (27–39) 16 (13–22) −6.367 <0.001 31 (81.6) 31 (77.5) 0.199 0.656 Volume (mL/kg) Total 53.9 (35.4–77.1) 33.1 (23.7–47.5) −3.779 <0.001 89.1 (51.7–138.2) 73.2 (26.9–95.0) −2.160 0.031 On the first day 2.8 (2.3–5.3) 2.4 (1.9–3.9) −1.355 0.176 – – Within 7 days 11.6 (7.9–15.9) 8.4 (6.0–10.9) −2.604 0.009 0 (0–20) 0 (0–19.1) −1.118 0.263 Within 28 days 29.7 (22.0–38.9) 21.1 (16.4–25.0) −3.369 0.001 38.9 (20.7–57.8) 26.3 (17.5–43.1) −0.954 0.340 Data are shown as median (interquartile), n (%) or mean ± standard deviation. Volume units is mL/kg.∗According to the GA, infants were divided into two groups, one was with a GA from ≥28 weeks to <32 weeks and the other was with a GA of <28 weeks. GA: Gestational age; RBCT: Red blood cell transfusion. A positive linear correlation between the total RBCT and sampling blood loss volumes before and after blood sampling management was demonstrated (before: r = 0.813, P < 0.001; after: r = 0.802, P < 0.001). When the sampling blood loss volume was <10 mL/kg, the RBCT rate was 1.7% (3/172); yet when the sampling blood loss volume was ≥30 mL/kg, the RBCT rate was 98.6% (138/140) [Supplementary Table 2, https://links.lww.com/CM9/B429]. The higher the sampling blood loss volume, the higher the RBCT rate. The total RBCT rate, number, and volume trended downward after starting management [Table 1]. Among all infants, the grades 1–2 IVH, 3–4 IVH, and NEC incidences were 23.8% (133/560), 4.1% (23/560), and 3.9% (22/560), respectively. After sampling management, grades 1–2 and 3–4 IVH incidences trended downward but the differences were insignificant. The NEC incidence did not increase after sampling management [Supplementary Table 3, https://links.lww.com/CM9/B429]. In preterm infants with a GA from ≥28 to <32 weeks, 24.0% (59/246) developed ROP (i.e., stages 1–5) before sampling management, and 11.4% (27/236) developed ROP after management; the ROP development rate was significantly reduced (P < 0.001). In preterm infants with a GA of <28 weeks, the ROP development rate before and after sampling management were 78.9% (30/38) and 62.5% (25/40), respectively; the ROP development rate insignificantly decreased. Only 1.6% (9/560) developed ROP progression (i.e., stages 3–5), and there was no difference in the ROP progression rate before and after sampling management [Supplementary Table 3, https://links.lww.com/CM9/B429]. In the binary logistic regression analysis, we included GA, BW, invasive respiratory support, bleeding, and infection as confounding factors. After excluding confounding factors, before sampling management, sampling blood loss (≥10 mL/kg) was a risk factor for ROP development (Odd ratio [OR], 3.098; 95% confidence interval [CI], 1.140–8.416; P = 0.027) in the early neonatal period. During the entire neonatal period, sampling blood loss (20–30 mL/kg) was a risk factor for ROP development (OR, 6.191; 95% CI, 1.494–26.555; P = 0.012). After management, sampling blood loss did not affect ROP development. Sampling blood loss did not affect ROP progression and no correlation was found between the number of RBCTs and ROP development or ROP progression. In the present study, we identified that blood sampling management markedly reduced the number of samples and the sampling blood loss in infants with a GA of <32 weeks and the RBCT volume in the early neonatal period. Sampling management had different effects on the RBCT of preterm infants with different GAs. The RBCT need was lower in preterm infants (≥28 and <32 weeks) than in extremely preterm infants (<28 weeks). The anemia may be more severe before the physiological phase of anemia, due to sampling blood loss. Thus, sampling management might reduce the anemia degree caused by iatrogenic blood loss and reduce the RBCT requirement at the early neonatal stage. The best way to minimize the RBCT risk for preterm infants is to reduce transfusion needs and decreasing laboratory blood sampling could be vital and effective. Sampling blood loss showed potential for modifying the ROP risk. The exact reason remains unclear, but we speculate that this might be due to the blood volume fluctuation caused by frequent and repeated sampling, which may lead to frequent oxygenation fluctuation and short-term hypoxia and increase the effect of oxidative stress, accelerating ROP.[2] After sampling management, the sampling blood loss volume decreased, and no adverse effects on ROP were observed, indicating that a specific sampling blood loss volume is required to affect ROP. Sampling management also markedly reduced the ROP incidences. Thus, reducing sampling may be a simple and effective way to minimize ROP. A prospective multi-center study in Turkey found that RBCT in preterm infants with a BW of <1500 g had a strong impact on the ROP progression (OR 2.384, P = 0.002).[3] And no correlation between RBCT and ROP development has been found,[3] which was consistent with our results. But no correlation between the number of RBCTs and ROP progression in this study. The reasons maybe as follows: firstly, comparing with Turkey's studies, the number of cases of ROP progression in this study was too small (9/560 vs. 414/6115); secondly, we analyzed the correlation between ROP and RBCT in the early and entire neonatal period, but the correlation between ROP and the RBCT during entire hospitalization was analyzed in Turkey; finally, the multi-center study in Turkey did not clearly indicate the indication of RBCTs, so it is unknown whether those multiple centers follow the same RBCT standard. At the same time, the speculated mechanisms were the free radical oxidative damage caused by iron overload and the rapidly increasing oxygen supply of the retina after RBCT.[3] ROP was related to hypoxia and the fluctuation of oxygen saturation.[2] However, the degree to which RBCT improves oxygen saturation and oxygen-carrying capacity is unclear. Further studies are needed to clarify the effect of RBCT on ROP in preterm infants. The decision to sample is the clinicians, based on the clinical condition of the preterm infant. Clinicians must be aware of the indications for each examination and plan the timing of sampling for preterm infants. Reducing the required blood volume per test is also an issue to address in the future. This study had limitations. This was a single-center study with limited information available, especially regarding preterm infants with a GA of <28 weeks. And other confounding factors should be considered, such as respiratory support and oxygen-related injury duration and the interaction among various indications. In conclusion, blood sampling management reduced the sampling blood loss and RBCT volumes and might be associated with preterm complications. Therefore, more attention should be paid to the current blood sampling protocols in the NICU, and more effective measures should be taken to reduce sampling blood loss. Acknowledgements The authors would like to thank Dr. Junjie Ying and Dr. Yang He from the Key Laboratory of Birth Defects and Related Diseases of Women and Children for their contributions to data analysis. At the same time, thank Professor Youping Li from the West China Evidence-Based Center for her guidance on quality management scheme design. Funding The study was supported by a grant from the National Natural Science Foundation of China (Nos. 82271749 and 82171710). Conflicts of interest None.

Objective Neonatal hypoxic-ischemic encephalopathy (HIE) endangers quality of life in children, and curative attempts are rarely effective. Neurogenesis plays an important role in neural repair following brain damage. This study aimed to investigate the role of telomerase reverse transcriptase (TERT) in neurogenesis after neonatal hypoxic-ischemic brain damage (HIBD). Methods Neonatal HIBD models were established in vivo (Sprague-Dawley rats, 7 days old) and in vitro (cultured neural stem cells, NSCs). Lentivirus and adenovirus transfection was used to induce TERT overexpression. Expression of TERT was detected by quantitative real-time PCR and immunofluorescence staining. NSCs apoptosis and proliferation were measured by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and cell counting assays, respectively. Migration and differentiation of NSCs were assessed by western blotting and immunofluorescence staining. Morris water maze test and modified neurological severity scores were conducted to evaluate the neurological function of rats. Results Overexpression of TERT attenuated apoptosis of NSCs; promoted proliferation, migration, and differentiation of NSCs; and induced myelination in the brains of neonatal rats after HIBD. Moreover, it reduced the impairment of learning, memory, and neurological function after HIBD in neonatal rats. In vitro findings indicated that the expression of Gli1 was increased after OGD, and overexpression of TERT further increased the expression of Gli1 in NSCs after OGD. Discussion TERT promotes neurogenesis and decreases neurological function injury after HIBD in neonatal rats. This neuroprotective pathway may provide a basis for developing therapeutic strategies for neonatal HIE. Furthermore, TERT may represent a target during neural injury and repair in patients with various diseases affecting the nervous system.

Backgrounds: Azithromycin mass drug administration (MDA) is a key part of the strategy for controlling trachoma. This systematic review aimed to comprehensively summarize the present studies of azithromycin MDA on trachoma; provide an overview of the impact of azithromycin MDA on trachoma in different districts; and explore the possible methods to enhance the effectiveness of azithromycin MDA in hyperendemic districts. Methods: PubMed, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, and ClinicalTrials.gov were searched up to February 2021 with no language restriction. Studies reporting the effect of azithromycin MDA on trachoma were included. Mathematical modeling studies, animal studies, case reports, and reviews were excluded. The trachomatous inflammation-follicular (TF) <5.0% was used to judge the effect of azithromycin MDA on eliminating trachoma as a public health problem. Two researchers independently conducted the selection process and risk of bias assessment. Results: A total of 1543 studies were screened, of which 67 studies including 13 cluster-randomized controlled trials and 54 non-randomized studies were included. The effect of azithromycin MDA on trachoma was closely related to the baseline prevalence in districts. For the districts with baseline prevalence between 5.0% and 9.9%, a single round of MDA achieved a TF <5.0%. For the districts with baseline between 10.0% and 29.9%, annual MDA for 3 to 5 years reduced TF <5.0%. However, for the districts with high level of baseline prevalence (TF >30.0%), especially with baseline TF >50.0%, annual MDA was unable to achieve the TF <5.0% even after 5 to 7 years of treatment. Quarterly MDA is more effective in controlling trachoma in these hyperendemic districts. Conclusions: Azithromycin MDA for controlling trachoma depends on the baseline prevalence. The recommendation by the World Health Organization that annual MDA for 3 to 5 years in the districts with TF baseline >10.0% is not appropriate for all eligible districts.

Objective To investigate the role and mechanism of stress-inducing protein Sestrin2 in the regulation of nerve cell autophagy in neonatal rats after hypoxic-ischemic brain damage (HIBD). Methods Eighty postnatal 10 days newborn Sprague-Dawley rats (test rats) were selected as research subjects. For the 60 test rats, the HIBD model was established; then according to the sacrifice time of 4, 8, 12, 24, 72 h after hypoxia-ischemia (HI), 60 test rats were included into 4, 8, 12, 24, 72 h after HI group, which was 20 cases in 24 h after HI group and the rest were 10 cases in each group. For the remaining 20 test rats, the right common carotid artery was separated but not ligated, no hypoxia treatment was performed and the sacrifice time corresponded to 24 h after HI group, and they were included into sham operation group (n=20). ① After obtained hippocampal tissue samples of rats in 4, 8, 12, 24, 72 h after HI group and sham operation group (10 cases in each group), western blotting was used to detect relative expression levels of Sestrin2, liver kinase B1 (LKB1), phosphorylated LKB1 (p-LKB1), adenosine monophosphate-activated protein kinase (AMPK), phosphorylated AMPK (p-AMPK), mammalian target of rapamycin (mTOR), phosphorylated mTOR (p-mTOR), autophagy-related protein Beclin1, microtubule-associated protein 1 light chain (LC)3, and apoptosis-related protein cleaved-caspase 3 (CC3) in hippocampus tissue of rats, and analysis of variance and least significant difference (LSD)-t methods were used to compare the above indicators among 6 groups or between 4, 8, 12, 24, 72 h after HI groups and sham operation group, respectively. ② After obtained cerebrum samples of remaining rats in 24 h after HI group and sham operation group (10 cases in each group), immunohistochemistry SP method was used to detect the expression levels of p-AMPK, LC3 and CC3, including integrated absorbance (IA) values and staining results in rats′ hippocampus tissue. And using t test to compare the IA values of the three indicators between two groups. This study was approved by the Animal Experimental Ethics Committee of Sichuan University [Approval No. SYXK (Chuan) 2013-185]. Results ① The results of western blotting showed that the levels of p-mTOR and CC3 in rats′ hippocampus tissue of 4 h and 8 h after HI groups were higher than those in sham operation group, respectively; the levels of Sestrin2, p-LKB1, p-AMPK, p-mTOR, Beclin1, LC3 and CC3 in rats′ hippocampus tissue of 12 h and 24 h after HI groups were higher than those in sham operation group, respectively; the levels of Sestrin2 and CC3 in rats′ hippocampus tissue of 72 h group after HI group were higher than those in sham operation group; and all of these differences were statistically significant (P 0.05). ② IA value detected results of immunohistochemical SP method showed that the expression levels of p-AMPK, LC3 and CC3 in rats′ hippocampus tissue of 24 h after HI group were (24 106±2 393), (41 892±4 094), (61 670±4 696), respectively, which were higher than those of (15 593±1 575), (18 941±2 131) and (20 279±1 912) in sham operation group, and the differences were statistically significant (t=9.398, P=0.035; t=15.723, P<0.001; t=25.812, P<0.001). Immunohistochemical SP method staining results showed that the expression level of p-AMPK, LC3 and CC3 positive cells were higher in rats′ hippocampus tissue of 24 h after HI group. Conclusion When HIBD occurs in postnatal 10 days newborn SD rats, the Sestrin2 in hippocampus tissue may be involved in the regulation of nerve cell autophagy and apoptosis via LKB1/AMPK/mTOR signaling pathway. Key words: Sestrin 2 protein, rat; Signal transduction; Hypoxia-ischemia, brain; Autophagy; Apoptosis; Blotting, western; Rats, Sprague-Dawley; Animals, newborn

IntroductionAzithromycin has been given for tropical infectious diseases such as trachoma and yaws by mass drug administration (MDA). As well as controlling the infectious disease in question, MDA may have a beneficial effect in reducing mortality in young children. However, the dose, formulation, frequency and duration of azithromycin used in certain infectious diseases may vary in different studies, and these differences may have impacts on the effectiveness of azithromycin MDA. Furthermore, whether the dose, formulation, frequency and duration are associated with the effectiveness of azithromycin for reducing child mortality—if indeed this effect can be confirmed—remain unknown. In this study, we will investigate whether different strategies such as different dose, formulation, frequency and duration affect the effectiveness of azithromycin MDA on the prevalence of certain infectious diseases or child mortality.Methods and analysisA narrative systematic review will be conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. PubMed, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, ClinicalTrials.gov and WHO International Clinical Trials Registry Platform will be searched. No language restrictions will be applied. All randomised/quasi-controlled trials, observational studies (cross-sectional studies, cohort studies and case–control studies), case series and registered protocols will be considered. Dose, duration, frequency, rounds and formulations of azithromycin used in MDA will be collected and reviewed. The outcomes will be disease prevalence/control in children and child mortality. Data from the individual studies will not be pooled.Ethics and disseminationFormal ethical approval is not required since data will be collected from published studies. This systematic review will be published in a peer-reviewed journal and presented at conference meetings.PROSPERO registration numberCRD42018114902

Background: Azithromycin mass drug administration (MDA) is a key strategy for reducing trachoma and eliminating yaws. Although WHO has issued the guideline for trachoma and yaws, the influence of MDA strategies including doses, formulation, duration, frequencies, and coverages on effectiveness of MDA remain unknown. Furthermore, possible off-target benefits of MDA in controlling malaria and reducing child mortality have been reported. The aim of this study was to determine the effectiveness of MDA strategies (doses, formulation, duration, frequencies and coverages) on prevalence of infectious diseases and child mortality. Methods: A systematic review and meta-analysis was conducted according to the PRISMA and protocol registered with PROSPERO. PubMed, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, ClinicalTrials.gov were searched up to May 2nd, 2019. Children aged up to 15 years old were included. The outcomes were disease prevalence/control in children and child mortality. Findings A total of 66 studies were included (50 on trachoma, seven on yaws, four on malaria and five on child mortality). For controlling trachoma, there is no significant difference between annual and biannual MDA, or between standard coverage and enhanced coverage. One round MDA may be enough for districts with active trachoma between 5%-10%. For the prevalence of active trachoma ≥10%, trachoma prevalence assessment may be postponed after three rounds. For eliminating yaws, both 30 mg/kg and 20 mg/kg doses effectively reduced the prevalence of yaws. For malaria, studies indicated that extra azithromycin distribution on low transmission season did not gain additional benefits. For child mortality, it showed a benefit trend toward azithromycin MDA, although the combined effect is not significant. Interpretation: Azithromycin MDA reduces the incidence of trachoma and yaws. The effectiveness of azithromycin MDA was influenced by its implementation strategies. As mortality is a rare event, the effect of azithromycin MDA on decreasing child mortality cannot be negated from current evidence.Funding Statement: This study was supported by grants from WHO (WHO Registration 2018/859223-0), the National Science Foundation of China (Nos. 81630038, 81971433, 81971428, 81300525), and Deep Underground Space Medical (No. DUGM201809).Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: A systematic review and meta-analysis was conducted according to the PRISMA and protocol registered with PROSPERO.

The memory dysfunction is one of the disastrous outcomes for perinatal hypoxia ischemia. Erythropoietin (EPO) has been demonstrated as a neuroprotective agent with multiple effects in a series of neurological diseases. We hypothesized that disruption of neural network including synapses and neurites would contribute to memory dysfunction induced by hypoxia ischemia. The aim of the present study was to elucidate the involvement of EPO on synaptogenesis and neurite repair following perinatal hypoxia ischemia. Using a neonatal hypoxia ischemia rat model, we found that EPO rescued hypoxia ischemia-induced decrease of synaptic proteins including Synapsin1 and PSD95 rather than GluR1 in the cortex and hippocampus. In addition, EPO reduced the expression of APP (an axonal injury marker), induced the expression of microtubule-associated protein MAP-2 (a dendritic marker), and restored axonal density after hypoxia ischemia. These changes contributed to improving electrophysiological properties of synapses and spatial memory performance. In summary, our data revealed an important role of EPO in synaptogenesis and neurite repair, providing a new insight into cellular mechanisms underlying cognitive and memory dysfunction associated with perinatal hypoxia ischemia.

Glycogen synthase kinase 3 beta (GSK-3β) plays an important role in neurological outcomes after brain injury. However, its roles and mechanisms in hypoxia-ischemia (HI) are unclear. Activation of mTOR complex 1 (mTORC1) has been proven to induce the synthesis of proteins associated with regeneration. We hypothesized that GSK-3β inhibition could activate the mTORC1 signaling pathway, which may reduce axonal injury and induce synaptic protein synthesis and functional recovery of synapses after HI. By analyzing a P7 rat model of cerebral HI and an in vitro ischemic (oxygen glucose deprivation) model, we found that GSK-3β inhibitors (GSK-3β siRNA or lithium chloride) activated mTORC1 signaling, leading to increased expression of synaptic proteins, including synapsin 1, PSD95, and GluR1, and the microtubule-associated protein Tau and decreased expression of the axonal injury-associated protein amyloid precursor protein. These changes contributed to attenuated axonal injury (decreased amyloid precursor protein staining and axonal loss by silver staining), improved electrophysiological properties of synapses, and enhanced spatial memory performance in the Morris water maze. However, inhibition of mTORC1 by rapamycin blocked the benefits induced by GSK-3β inhibition, suggesting that GSK-3β inhibition induces synaptogenesis and axonal repair via mTORC1 signaling, which may benefit neonatal rats subjected to HI.