High-Pressure Induced Continuous Structural Evolution of Kagome Antiferromagnet MgMn3(OH)6Cl2: A Structural Analogue to Quantum Spin Liquid Herbertsmithite.

MgMn3(OH)6Cl2 serves readily as the classical Heisenberg kagome antiferromagnet lattice spin frustration material, due to its similarity to herbertsmithite in composition and crystal structure. In this work, nanosheets of MgMn3(OH)6Cl2 are synthesized through a solid-phase reaction. Low-temperature magnetic measurements revealed two antiferromagnetic transitions, occurring at ∼8 and 55 K, respectively. Utilizing high-pressure synchrotron radiation X-ray diffraction techniques, the topological structural evolution of MgMn3(OH)6Cl2 under pressures up to 24.8 GPa was investigated. The sample undergoes a second-order structural phase transition from the rhombohedral phase to the monoclinic phase at pressures exceeding 7.8 GPa. Accompanying the disappearance of the Fano-like line shape in the high-pressure Raman spectra were the emergence of new Raman active modes and discontinuities in the variations of Raman shifts in the high-frequency region. The phase transition to a structure with lower symmetry was attributed to the pressure-induced enhancement of cooperative Jahn-Teller distortion, which is caused by the mutual substitution of Mn2+ ions from the kagome layer and Mg2+ ions from the triangular interlayer. High-pressure ultraviolet-visible absorption measurements support the structural evolution. This research provides a robust experimental approach and physical insights for further exploration of classical geometrical frustration materials with kagome lattice.

[Impact of assisted reproductive technology on birth weight discordance in twins]. / è¾ åŠ©ç”Ÿæ®–æŠ€æœ¯å¯¹åŒèƒŽå‡ºç”Ÿä½“é‡ä¸ä¸€è‡´çš„å½±å“.

OBJECTIVES: To explore the association between assisted reproductive technology (ART) and birth weight discordance in twins (BWDT). METHODS: A retrospective analysis was conducted on twin infants born between January 2011 and December 2020 at the Third Affiliated Hospital of Guangzhou Medical University, with complete basic birth data. The impact of ART on the occurrence of BWDT was identified by the multivariate logistic regression analysis. RESULTS: A total of 3 974 pairs of twins were included, with 1 431 conceived naturally and 2 543 through ART. Neonates in the ART group had higher birth weights than those in the naturally conceived group (P<0.001). The incidence of BWDT was lower in the ART group compared to the naturally conceived group (16.17% vs 21.09%, P<0.001). The multivariate logistic regression analysis, adjusting for confounding factors such as maternal age, parity, pre-pregnancy body mass index, gestational diabetes, hypothyroidism, gestational age, and chorionic properties, showed no significant difference in the risk of BWDT between the ART and naturally conceived groups (P>0.05). CONCLUSIONS: ART is not associated with the risk of BWDT.

The injection-production performance of an enhanced geothermal system considering fracture network complexity and thermo-hydro-mechanical coupling in numerical simulations.

The effect of fracture networks on EGS performance remains worth further investigation to guide the formulation of geothermal extraction strategy. We established models that account for thermo-hydraulic-mechanical (THM) coupling and that are based on the framework of discrete fracture network (DFN) to evaluate the heat extraction performance in deep-seated fractured reservoir. Our numerical results reveal that the zones of temperature, pressure, and stress perturbation diffuse asynchronously during the circulation of injection-production, and the stress perturbation always lags behind the other two. Furthermore, the effects of the fracture network characteristics including randomness, geometry, length, aperture, and injection parameters on the heat production are quantitatively investigated. Under the same number of fractures, different network geometry leads to different EGS production performance, the network with horizontal fracture set shows better thermal extraction performance but poor injection performance, which is because the fracture dip affects the thermal evolution on the horizontal plane. The effect of fracture length on EGS performance highly depends on its orientation, the excessive increase of fracture length towards injection-production wells is detrimental to heat extraction. The fracture aperture affects the working fluid transport and thus the EGS performance, the fractured reservoir with smaller fracture aperture shows the worse fluid flow performance but the better geothermal extraction performance, thus we believe that the optimal fracture aperture should be kept at a level of 0.5-1.0 mm in a self-propping fractured granitic system. The main influence of injection parameters on thermal extraction from the fractured reservoirs is the injection mass rate, because a high injection rate results in significant solid responses, including failure stress concentration, decreased safety factor, and increased permeability, which occur in those fractures that are originally connected to the injection well. These results of our research and the insights obtained have important implications for deep geothermal geoengineering activities.

Structural phase transformation of quantum spin liquid herbertsmithite via pressure induced enhancement of the cooperative Jahn-Teller effect and antisite disorder.

Herbertsmithite, Cu3Zn(OH)6Cl2, serves as one of the most promising candidates for quantum spin liquids with a perfect quantum kagome Heisenberg antiferromagnetic system. It can comprise an ideal model system for studying the compression response of the unique structure as well as exotic properties of kagome quantum spin liquid materials, which is of fundamental importance from both scientific and technological viewpoints. In this work, the structural evolution of herbertsmithite was investigated via in situ X-ray diffraction and Raman scattering techniques up to 30 GPa. The trigonal herbertsmithite structure transformed into a monoclinic clinoatacamite-like structure at 12.6 GPa. High pressure seems to act in a reverse way as Zn-doping for herbertsmithite, with the distortion degree of the system changing continuously. The occurrence of the displacive and reversible phase transition between the polymorphs is a consequence of the interplay between the external pressure and cooperative Jahn-Teller (JT) effect, aided by the presence of antisite mutual substitution of magnetic Cu2+ ions and nonmagnetic Zn2+ ions between the kagome layer and interlayer sites.

Efficacy of inhaled nitric oxide in preterm infants ≤ 34 weeks: a systematic review and meta-analysis of randomized controlled trials.

Background: The effect of inhaled nitric oxide (iNO) in neonates >34 weeks on improving respiration is well documented. However, the efficacy of iNO in preterm infants ≤34 weeks remains controversial. Objectives: The main purpose of this review is to assess the effectiveness and safety of iNO treatment in preterm infants ≤34 weeks. Search methods: We systematically searched PubMed, Embase and Cochrane Libraries from their inception to 1 June 2023. We also reviewed the reference lists of retrieved studies. Selection criteria: Our study involved randomized controlled trials on preterm infants ≤34 weeks, especially those receiving iNO treatment, and mainly assessed outcomes such as bronchopulmonary dysplasia (BPD) and mortality. Two authors independently reviewed these trials, extracted data, and evaluated study biases. Disagreements were resolved by consensus. We used the GRADE method to assess evidence quality. Results: Our research included a total of 17 studies involving 4,080 neonates and 7 follow-up studies. The synthesis of results showed that in neonates, iNO treatment reduced the incidence of BPD (RR: 0.92; 95% CI: 0.86-0.98). It also decreased the composite outcome of death or BPD (RR: 0.94; 95% CI: 0.90-0.98), without increasing the risk of short-term (such as intraventricular hemorrhage, periventricular leukomalacia) and long-term neurological outcomes (including Bayley mental developmental index <70, cerebral palsy and neurodevelopmental impairment). Furthermore, iNO did not significantly affect other neonatal complications like sepsis, pulmonary hemorrhage, necrotizing enterocolitis, and symptomatic patent ductus arteriosus. Subgroup analysis revealed that iNO significantly reduced BPD incidence in neonates at 36 weeks under specific intervention conditions, including age less than 3 days, birth weight over 1,000 g, iNO dose of 10 ppm or higher, or treatment duration exceeding 7 days (p < 0.05). Conclusion: Inhaled NO reduced the incidence of BPD in neonates at 36 weeks of gestation, and the effect of the treatment depended on neonatal age, birth weight, duration and dose of iNO. Therefore, iNO can be considered a promising treatment for the potential prevention of BPD in premature infants. More data, however, would be needed to support nitric oxide registration in this specific patient population, to minimize its off-label use.

Mothers with hypertensive disorders of pregnancy increased risk of periventricular leukomalacia in extremely preterm or extremely low birth weight infants: A propensity score analysis.

Background: At present, the conclusions about the impact of hypertensive disorders of pregnancy (HDP) on the clinical outcomes of preterm infants are inconsistent. This study used the propensity score matching (PSM) analysis to evaluate the effect of HDP on clinical outcomes of extremely preterm or extremely low birth weight (EP/ELBW) infants. Methods: Retrospective analysis was performed on the EP/ELBW infants discharged from 26 tertiary neonatal intensive care units or died during hospitalization from 2008 to 2017, who were divided into HDP group and non-HDP group. The six covariates including sex, gestational age, birth weight, twin or multiple pregnancy, antenatal steroids administration, and conception method were matched through the PSM method at a ratio of 1:1. The survival rate at discharge and the major clinical complications were compared between the two groups. Results: After matching the six covariates, compared with the non-HDP group, there was no significant difference in the survival rate at discharge (64 vs. 63.2%, p > 0.05), the incidence of bronchopulmonary dysplasia (BPD) or moderate to severe BPD in the HDP group (58.3 vs. 54.9%, p > 0.05; 5.2 vs. 6.2%, p > 0.05). The incidence of periventricular leukomalacia (PVL) in the HDP group was significantly increased (5.7 vs. 1.9%, p < 0.05). Conclusions: HDP increased the risk of PVL in EP/ELBW infants, but had no significant effect on the survival rate at discharge, or the occurrence of other complications.

Short term outcomes of extremely low birth weight infants from a multicenter cohort study in Guangdong of China.

With the increase in extremely low birth weight (ELBW) infants, their outcome attracted worldwide attention. However, in China, the related studies are rare. The hospitalized records of ELBW infants discharged from twenty-six neonatal intensive care units in Guangdong Province of China during 2008-2017 were analyzed. A total of 2575 ELBW infants were enrolled and the overall survival rate was 55.11%. From 2008 to 2017, the number of ELBW infants increased rapidly from 91 to 466, and the survival rate improved steadily from 41.76% to 62.02%. Increased survival is closely related to birth weight (BW), regional economic development, and specialized hospital. The incidence of complications was neonatal respiratory distress syndrome (85.2%), oxygen dependency at 28 days (63.7%), retinopathy of prematurity (39.3%), intraventricular hemorrhage (29.4%), necrotizing enterocolitis (12.0%), and periventricular leukomalacia (8.0%). Among the 1156 nonsurvivors, 90.0% of infants died during the neonatal period (≤ 28 days). A total of 768 ELBW infants died after treatment withdrawal, for reasons of economic and/or poor outcome. The number of ELBW infants is increasing in Guangdong Province of China, and the overall survival rate is improving steadily.

[Sex differences in clinical outcomes of extremely preterm infants/extremely low birth weight infants: a propensity score matching study]. / è¶ æ—©äº§å„¿/è¶ ä½Žå‡ºç”Ÿä½“é‡å„¿ä¸´åºŠç»“å±€çš„æ€§åˆ«å·®å¼‚ï¼šä¸€é¡¹å€¾å‘æ€§è¯„åˆ†åŒ¹é ç ”ç©¶.

OBJECTIVES: To study the effect of sex on the clinical outcome of extremely preterm infants (EPIs)/extremely low birth weight infants (ELBWIs) by propensity score matching. METHODS: A retrospective analysis was performed for the medical data of 731 EPIs or ELBWIs who were admitted from January 1, 2011 to December 31, 2020. These infants were divided into two groups: male and female. A propensity score matching analysis was performed at a ratio of 1:1. The matching variables included gestational age, birth weight, percentage of withdrawal from active treatment, percentage of small-for-gestational-age infant, percentage of use of pulmonary surfactant, percentage of 1-minute Apgar score ≤3, percentage of mechanical ventilation, duration of mechanical ventilation, percentage of antenatal use of inadequate glucocorticoids, and percentage of hypertensive disorders in pregnancy. The two groups were compared in the incidence rate of main complications during hospitalization and the rate of survival at discharge. RESULTS: Before matching, compared with the female group, the male group had significantly higher incidence rates of neonatal respiratory distress syndrome, bronchopulmonary dysplasia (BPD), severe intraventricular hemorrhage, periventricular leukomalacia, necrotizing enterocolitis, and patent ductus arteriosus (P<0.05), while after matching, the male group only had a significantly higher incidence rate of BPD than the female group (P<0.05). There was no significant difference in the rate of survival at discharge between the two groups before and after matching (P>0.05). CONCLUSIONS: Male EPIs/ELBWIs have a higher risk of BPD than female EPIs/ELBWIs, but male and female EPIs/ELBWIs tend to have similar outcomes.

Increased Risk for Respiratory Complications in Male Extremely Preterm Infants: A Propensity Score Matching Study.

Background: Many factors can affect the clinical outcome of extremely premature infants (EPIs), but the effect of sex is paradoxical. This study used propensity score matching to adjust baseline information to reassess the clinical outcome of EPIs based on sex. Methods: A retrospective analysis was performed on EPIs admitted in the Department of Neonatology of the Third Affiliated Hospital of Guangzhou Medical University from 2011 to 2020. A propensity score matching (PSM) analysis was used to adjust the confounding factors including gestational age, birth weight, 1-minute Apgar score ≤ 3, withholding or withdrawing life-sustaining treatment(WWLST), mechanical ventilation, duration of mechanical ventilation, the mother with advanced age (≥35 years old), complete-course antenatal steroid therapy and hypertensive disorders of pregnancy. The survival rate at discharge and the incidence of major complications were evaluated between the male and female groups. Results: A total of 439 EPIs were included, and 240 (54.7%) infants were males. After matching the nine confounding factors, 148 pairs of infants were finally enrolled. There was no significant difference in the survival rate at discharge, as well as the mortality of activating treatment or WWLST between the two groups (all P>0.05). However, the incidence of respiratory distress syndrome, bronchopulmonary dysplasia (BPD), and moderate to severe BPD in the male group was significantly increased (all P<0.01), especially at birth weight between 750 and 999 grams. Conclusions: The male EPIs have a higher risk of respiratory complications than females, particularly at 750 to 999 grams of birth weight.

Interplay between External High Pressure and Intrinsic Jahn-Teller Effect in the Compression Behavior of Clinoatacamite.

Clinoatacamite (γ-Cu2(OH)3Cl) possesses a geometrically frustrated kagome lattice for the S = 1/2 antiferromagnetic spin system. Thus, it is deemed as the mother compound of many promising quantum spin liquid materials. Here, we synthesized clinoatacamite consisting of homogeneous octahedron-like particles with an average size of 1-2 µm via a hydrothermal strategy. Clinoatacamite crystallizes in a monoclinic lattice composed of Jahn-Teller distorted Cu(OH)6 and Cu(OH)4Cl2 octahedrons. The bonding nature of clinoatacamite is characterized using Raman scattering and FTIR absorption spectroscopies, which reveal the existence of trimeric hydrogen bonds. The magnetic measurements indicate that at temperatures below about 6 K, the magnetic response of the prepared samples is dominated by weak ferromagnetic contributions. The compression behavior is investigated by in situ high-pressure synchrotron radiation X-ray diffraction and Raman scattering spectroscopy. An isostructural phase transition is observed at about 8.4 GPa, which is evidenced by the anomalies in the variation curves of the lattice parameters and Raman scattering frequencies with pressure. The occurrence of the isostructural phase transition is attributed to the competition and cooperation of the external pressure and intrinsic Jahn-Teller effect, together with the interplay of intrastructural hydrogen bonding.

The inhibition of enterocyte proliferation by lithocholic acid exacerbates necrotizing enterocolitis through downregulating the Wnt/ß-catenin signalling pathway.

OBJECTIVES: Necrotizing enterocolitis (NEC) is a catastrophic gastrointestinal emergency in preterm infants, whose exact aetiology remains unknown. The role of lithocholic acid (LCA), a key component of secondary bile acids (BAs), in NEC is unclear. METHODS: Clinical data were collected to analyse the changes of BAs in NEC patients. In vitro studies, the cell proliferation and cell death were assessed. In vivo experiments, the newborn rats were administered with low or high dose of LCA and further induced NEC. RESULTS: Clinically, compared with control group, total BAs in the NEC patients were significantly higher when NEC occurred. In vitro, LCA treatment significantly inhibited the cell proliferation through arresting cell cycle at G1/S phase without inducing apoptosis or necroptosis. Mechanistically, the Wnt/ß-catenin pathway was involved. In vivo, LCA inhibited intestinal cell proliferation leading to disruption of intestinal barrier, and thereby increased the severity of NEC. Specifically, LCA supplementation caused higher levels of FITC-labelled dextran in serum, reduced PCNA expression and inhibited the activity of Wnt/ß-catenin pathway in enterocytes. The LC-MS/MS test found that LCA was significantly higher in intestinal tissue of NEC group, and more obviously in the NEC-L and NEC-H group compared with the DM group. CONCLUSION: LCA exacerbates NEC by inhibiting intestinal cell proliferation through downregulating the Wnt/ß-catenin pathway.

Incidence of extrauterine growth retardation and its risk factors in very preterm infants during hospitalization: a multicenter prospective study. / ä½é™¢æžæ—©äº§å„¿å®«å¤–ç”Ÿé•¿è¿Ÿç¼“åŠç›¸å ³å› ç´ çš„å¤šä¸­å¿ƒå‰çž»æ€§ç ”ç©¶.

OBJECTIVES: To investigate the incidence of extrauterine growth retardation (EUGR) and its risk factors in very preterm infants (VPIs) during hospitalization in China. METHODS: A prospective multicenter study was performed on the medical data of 2 514 VPIs who were hospitalized in the department of neonatology in 28 hospitals from 7 areas of China between September 2019 and December 2020. According to the presence or absence of EUGR based on the evaluation of body weight at the corrected gestational age of 36 weeks or at discharge, the VPIs were classified to two groups: EUGR group (n=1 189) and non-EUGR (n=1 325). The clinical features were compared between the two groups, and the incidence of EUGR and risk factors for EUGR were examined. RESULTS: The incidence of EUGR was 47.30% (1 189/2 514) evaluated by weight. The multivariate logistic regression analysis showed that higher weight growth velocity after regaining birth weight and higher cumulative calorie intake during the first week of hospitalization were protective factors against EUGR (P<0.05), while small-for-gestational-age birth, prolonged time to the initiation of total enteral feeding, prolonged cumulative fasting time, lower breast milk intake before starting human milk fortifiers, prolonged time to the initiation of full fortified feeding, and moderate-to-severe bronchopulmonary dysplasia were risk factors for EUGR (P<0.05). CONCLUSIONS: It is crucial to reduce the incidence of EUGR by achieving total enteral feeding as early as possible, strengthening breastfeeding, increasing calorie intake in the first week after birth, improving the velocity of weight gain, and preventing moderate-severe bronchopulmonary dysplasia in VPIs.

Clinical treatment outcomes and their changes in extremely preterm twins: a multicenter retrospective study in Guangdong Province, China. / è¶ æœªæˆç†ŸåŒèƒŽå„¿ä¸´åºŠæ•‘æ²»ç»“å±€åŠå˜åŒ–åˆ†æžï¼šä¸€é¡¹å¹¿ä¸œçœå¤šä¸­å¿ƒå›žé¡¾æ€§ç ”ç©¶.

OBJECTIVES: To investigate the clinical treatment outcomes and the changes of the outcomes over time in extremely preterm twins in Guangdong Province, China. METHODS: A retrospective analysis was performed for 269 pairs of extremely preterm twins with a gestational age of <28 weeks who were admitted to the department of neonatology in 26 grade A tertiary hospitals in Guangdong Province from January 2008 to December 2017. According to the admission time, they were divided into two groups: 2008-2012 and 2013-2017. Besides, each pair of twins was divided into the heavier infant and the lighter infant subgroups according to birth weight. The perinatal data of mothers and hospitalization data of neonates were collected. The survival rate of twins and the incidence rate of complications were compared between the 2008-2012 and 2013-2017 groups. RESULTS: Compared with the 2008-2012 group, the 2013-2017 group (both the heavier infant and lighter infant subgroups) had lower incidence rates of severe asphyxia and smaller head circumference at birth (P<0.05). The mortality rates of both of the twins, the heavier infant of the twins, and the lighter infant of the twins were lower in the 2013-2017 group compared with the 2008-2012 group (P<0.05). Compared with the 2008-2012 group, the 2013-2017 group (both the heavier infant and lighter infant subgroups) had lower incidence rates of pulmonary hemorrhage, patent ductus arteriosus (PDA), periventricular-intraventricular hemorrhage (P-IVH), and neonatal respiratory distress syndrome (NRDS) and a higher incidence rate of bronchopulmonary dysplasia (P<0.05). CONCLUSIONS: There is a significant increase in the survival rate over time in extremely preterm twins with a gestational age of <28 weeks in the 26 grade A tertiary hospitals in Guangdong Province. The incidences of severe asphyxia, pulmonary hemorrhage, PDA, P-IVH, and NRDS decrease in both the heavier and lighter infants of the twins, but the incidence of bronchopulmonary dysplasia increases. With the improvement of diagnosis and treatment, the multidisciplinary collaboration between different fields of fetal medicine including prenatal diagnosis, obstetrics, and neonatology is needed in the future to jointly develop management strategies for twin pregnancy.

Pressure-Induced Variation of the Crystal Stacking Order in the Hydrogen-Bonded Quasi-Two-Dimensional Layered Material Cu(OH)Cl.

The crystal stacking order plays a crucial role in determining the structure and physical properties of 2D layered materials. A variation in the stacking sequence of adjacent 2D building blocks causes drastic changes in their functionalities. In this work, the structural variation of belloite (Cu(OH)Cl), as a function of pressure, is presented. Through in situ synchrotron X-ray diffraction and Raman scattering studies, in combination with first-principles theoretical simulations, a structural transformation from the initial monoclinic phase into an orthorhombic one has been established at 18.7 GPa, featuring variations in the stacking sequence of the tectonic monolayers. In the monoclinic phase, they are arranged in an AAAA sequence. While in the orthorhombic phase, the monolayers are stacked in an ABAB sequence. Such phenomena are similar to those observed in van der Waals 2D materials, with pressure-induced changes in the stacking order between layers. In addition, an isostructural phase transition within the initial monoclinic phase is also observed to occur at 12.9-16 GPa, which is associated with layer-sliding and a change in hydrogen bond configuration. These results show that Cu(OH)Cl, as well as other hydrogen-bonded 2D layered materials, can provide a convenient platform for studying the effects of the crystal stacking order.

Efficacy and safety of surfactant administration via thin catheter in preterm infants with neonatal respiratory distress syndrome: A systematic review and meta-analysis.

OBJECTIVE: The efficacy and safety of surfactant administration via thin catheter in preterm infants with neonatal respiratory distress syndrome (NRDS) was investigated. METHODS: PubMed, Embase, Cochrane Library, and Web of Science databases were searched to identify randomized controlled trials (RCTs) that comparing thin catheter technique with intubation for surfactant delivery in preterm infants with NRDS. RESULTS: Thirteen RCTs (1931 infants) were included in the meta-analysis. The use of thin catheter technique decreased the incidences of bronchopulmonary dysplasia (BPD), pneumothorax, and hemodynamically significant patent ductus arteriosus (hsPDA) (risk ratio [RR]: 0.59, 95% confidence interval [CI]: 0.46-0.75, p < .0001; RR: 0.60, 95% CI: 0.39-0.93, p = .02 and RR: 0.88, 95% CI: 0.78-1.00, p = .04, respectively). In addition, infants in the intervention group required less mechanical ventilation within 72 h of life or during hospitalization (RR: 0.60, 95% CI: 0.48-0.75, p < .00001 and RR: 0.64, 95% CI: 0.49-0.82, p = .0005, respectively) compared with infants in the control group. However, the rate of surfactant reflux was higher in the intervention group than that in the control group (RR: 2.12, 95% CI: 1.37-3.29, p = .0008). There were no significant differences in mortality and other outcomes between the two groups. CONCLUSION: The administration of surfactant via thin catheter could lower the requirement for mechanical ventilation, and decrease the incidence of BPD, pneumothorax, and hsPDA.

Umbilical Cord Blood-Derived Exosomes From Very Preterm Infants With Bronchopulmonary Dysplasia Impaired Endothelial Angiogenesis: Roles of Exosomal MicroRNAs.

Premature infants have a high risk of bronchopulmonary dysplasia (BPD), which is characterized by abnormal development of alveoli and pulmonary vessels. Exosomes and exosomal miRNAs (EXO-miRNAs) from bronchoalveolar lavage fluid are involved in the development of BPD and might serve as predictive biomarkers for BPD. However, the roles of exosomes and EXO-miRNAs from umbilical cord blood of BPD infants in regulating angiogenesis are yet to be elucidated. In this study, we showed that umbilical cord blood-derived exosomes from BPD infants impaired angiogenesis in vitro. Next-generation sequencing of EXO-miRNAs from preterm infants without (NBPD group) or with BPD (BPD group) uncovered a total of 418 differentially expressed (DE) EXO-miRNAs. These DE EXO-miRNAs were primarily enriched in cellular function-associated pathways including the PI3K/Akt and angiogenesis-related signaling pathways. Among those EXO-miRNAs which are associated with PI3K/Akt and angiogenesis-related signaling pathways, BPD reduced the expression of hsa-miR-103a-3p and hsa-miR-185-5p exhibiting the most significant reduction (14.3% and 23.1% of NBPD group, respectively); BPD increased hsa-miR-200a-3p expression by 2.64 folds of the NBPD group. Furthermore, overexpression of hsa-miR-103a-3p and hsa-miR-185-5p in normal human umbilical vein endothelial cells (HUVECs) significantly enhanced endothelial cell proliferation, tube formation, and cell migration, whereas overexpressing hsa-miR-200a-3p inhibited these cellular responses. This study demonstrates that exosomes derived from umbilical cord blood of BPD infants impair angiogenesis, possibly via DE EXO-miRNAs, which might contribute to the development of BPD.

[Effect of weight growth velocity in the early stage after birth on neurodevelopment of preterm infants at the corrected age of 12 months].

OBJECTIVE: To study the effect of weight growth velocity in the early stage after birth on the neurodevelopment of preterm infants at the corrected age of 12 months. METHODS: Related data were collected from the preterm infants who were discharged from the Department of Neonatology, Third Affiliated Hospital of Guangzhou Medical University, from July 1, 2015 to December 31, 2019 and were followed up at the outpatient service of high-risk infants. According to the weight growth velocity from birth to the corrected gestational age of 40 weeks, the infants were divided into two groups: low velocity [< 10 g/(kg·d); n=21] and high velocity [≥10 g/(kg·d); n=87]. At the corrected ages of 3, 6, and 12 months, Gesell Developmental Schedules were used to evaluate and compare neurodevelopment between the two groups. RESULTS: At the corrected age of 12 months, the low velocity group had a significantly lower score of fine motor (P < 0.05) and a significantly higher abnormal rate of language ability score compared with high velocity (P < 0.05). For the preterm infants with a birth weight of < 1 500 g or ≥1 500 g, the low velocity group had a significantly lower score of fine motor than the high velocity group (P < 0.05); for the preterm infants with a birth weight of ≥1 500 g, the low velocity group had a significantly higher abnormal rate of language ability score than the high velocity group (P < 0.05). CONCLUSIONS: The weight growth velocity from birth to the corrected age of 40 weeks affects the development of fine motor and language in preterm infants at the corrected age of 12 months; however it needs to be further verified by large-sample studies.

InOOH Bulk Crystals and Ultrathin Nanowires under Compression.

InOOH bulk crystals and ultrathin nanowires have been investigated under high pressures by in situ synchrotron radiation X-ray diffraction measurements at ambient temperature. The anisotropic compression indicates that the b-axis is more compressible than the other two axes in InOOH under hydrostatic conditions. Two inflection points, which are associated with the hydrogen-bond strengthening, can be reflected in the plots of b/c ratio versus pressure (b/c-P plots). The size-induced enhancement of the bulk modulus can be visualized from the P-V plots. By comparing the differences in the compression of bulk InOOH and ultrathin nanowires, it is validated that the nanosize effects play an important role in the high-pressure behaviors of InOOH.

Enhanced Anti-Mold Property and Mechanism Description of Ag/TiO2 Wood-Based Nanocomposites Formation by Ultrasound- and Vacuum-Impregnation.

Ag/TiO2 wood-based nanocomposites were prepared by the methods of ultrasound impregnation and vacuum impregnation. The as-prepared samples were characterized by field emission scanning electron microscopy (FESEM), energy-dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), mercury intrusion porosimetry (MIP), and water contact angles (WCAs). The anti-mold properties of the Ag/TiO2 wood-based nanocomposites were improved by 14 times compared to those of the original wood. The nano-Ag/TiO2, which was impregnated in the tracheid and attached to the cell walls, was able to form a two-stage rough structure and reduce the number of hydroxyl functional groups on the wood surfaces. The resulting decline of wood hydrophobic and equilibrium moisture content (EMC) destroyed the moisture environment necessary for mold survival. Ag/TiO2 was deposited in the wood pores, which reduced the number and volume of pores and blocked the path of mold infection. Thus, the anti-mold properties of the Ag/TiO2 wood-based nanocomposite were improved by cutting off the water source and blocking the mold infection path. This study reveals the anti-mold mechanism of Ag/TiO2 wood-based nanocomposites and provides a feasible pathway for wood-based nanocomposites with anti-mold functions.

Lactoferrin-induced myeloid-derived suppressor cell therapy attenuates pathologic inflammatory conditions in newborn mice.

Inflammation plays a critical role in the development of severe neonatal morbidities. Myeloid-derived suppressor cells (MDSCs) were recently implicated in the regulation of immune responses in newborns. Here, we report that the presence of MDSCs and their functional activity in infants are closely associated with the maturity of newborns and the presence of lactoferrin (LF) in serum. Low amounts of MDSCs at birth predicted the development of severe pathology in preterm infants - necrotizing enterocolitis (NEC). In vitro treatment of newborn neutrophils and monocytes with LF converted these cells to MDSCs via the LRP2 receptor and activation of the NF-κB transcription factor. Decrease in the expression of LRP2 was responsible for the loss of sensitivity of adult myeloid cells to LF. LF-induced MDSCs (LF-MDSCs) were effective in the treatment of newborn mice with NEC, acting by blocking inflammation, resulting in increased survival. LF-MDSCs were more effective than treatment with LF protein alone. In addition to affecting NEC, LF-MDSCs demonstrated potent ability to control ovalbumin-induced (OVA-induced) lung inflammation, dextran sulfate sodium-induced (DSS-induced) colitis, and concanavalin A-induced (ConA-induced) hepatitis. These results suggest that cell therapy with LF-MDSCs may provide potent therapeutic benefits in infants with various pathological conditions associated with dysregulated inflammation.