A self-supervised spatio-temporal attention network for video-based 3D infant pose estimation.

General movement and pose assessment of infants is crucial for the early detection of cerebral palsy (CP). Nevertheless, most human pose estimation methods, in 2D or 3D, focus on adults due to the lack of large datasets and pose annotations on infants. To solve these problems, here we present a model known as YOLO-infantPose, which has been fine-tuned, for infant pose estimation in 2D. We further propose a self-supervised model called STAPose3D for 3D infant pose estimation based on videos. We employ multi-view video data during the training process as a strategy to address the challenge posed by the absence of 3D pose annotations. STAPose3D combines temporal convolution, temporal attention, and graph attention to jointly learn spatio-temporal features of infant pose. Our methods are summarized into two stages: applying YOLO-infantPose on input videos, followed by lifting these 2D poses along with respective confidences for every joint to 3D. The employment of the best-performing 2D detector in the first stage significantly improves the precision of 3D pose estimation. We reveal that fine-tuned YOLO-infantPose outperforms other models tested on our clinical dataset as well as two public datasets MINI-RGBD and YouTube-Infant dataset. Results from our infant movement video dataset demonstrate that STAPose3D effectively comprehends the spatio-temporal features among different views and significantly improves the performance of 3D infant pose estimation in videos. Finally, we explore the clinical application of our method for general movement assessment (GMA) in a clinical dataset annotated as normal writhing movements or abnormal monotonic movements according to the GMA standards. We show that the 3D pose estimation results produced by our STAPose3D model significantly boost the GMA prediction performance than 2D pose estimation. Our code is available at github.com/wwYinYin/STAPose3D.

Cough symptoms in children following COVID-19: a single-center retrospective study.

Background: Cough is the most common respiratory symptom in children with mild coronavirus disease 2019 (COVID-19); however, evidence regarding the duration and severity of COVID-19-related cough is sparse. Herein, we investigated the correlation between cough severity/duration and disease duration in children with allergic diseases following COVID-19. Methods: This single-center, retrospective case-control study was conducted at the Department of Pediatrics, Peking University Third Hospital, from February 6-13, 2023. Children aged 0-16 completed a questionnaire survey collecting basic information and weekly cough scores for 8 consecutive weeks after COVID-19 in December 2022. The Kaplan-Meier method was used to draw event curves, and the log-rank method was used to compare inter-group differences. Stepwise regression was applied for multivariate analysis of correlations between age, sex, allergic diseases, and the degree and duration of cough following COVID-19. Results: Overall, 686 children were included, of whom 183 (26.7%) had allergic diseases and 503 (73.3%) did not. Kaplan-Meier analysis identified significant differences between patients with and without allergic disease (log-rank test, P = 0.002) and between patients with no allergic disease and those with one and more than one allergic disease (log-rank test, P = 0.003). Multivariate regression identified a link between the presence of more than one allergic disease and coughing for >4 weeks after infection (P < 0.001). Allergic disease was the primary factor linked to cough symptoms lasting 8 weeks and cough severity (P < 0.001). Conclusions: Allergic disease contributes to the prolonged duration and severity of coughing in children with mild COVID-19.

Curriculum and assessment tool for less invasive surfactant administration: an international Delphi consensus study.

BACKGROUND: Training and assessment of operator competence for the less invasive surfactant administration (LISA) procedure vary. This study aimed to obtain international expert consensus on LISA training (LISA curriculum (LISA-CUR)) and assessment (LISA assessment tool (LISA-AT)). METHODS: From February to July 2022, an international three-round Delphi process gathered opinions from LISA experts (researchers, curriculum developers, and clinical educators) on a list of items to be included in a LISA-CUR and LISA-AT (Round 1). The experts rated the importance of each item (Round 2). Items supported by more than 80% consensus were included. All experts were asked to approve or reject the final LISA-CUR and LISA-AT (Round 3). RESULTS: A total of 153 experts from 14 countries participated in Round 1, and the response rate for Rounds 2 and 3 was >80%. Round 1 identified 44 items for LISA-CUR and 22 for LISA-AT. Round 2 excluded 15 items for the LISA-CUR and 7 items for the LISA-AT. Round 3 resulted in a strong consensus (99-100%) for the final 29 items for the LISA-CUR and 15 items for the LISA-AT. CONCLUSIONS: This Delphi process established an international consensus on a training curriculum and content evidence for the assessment of LISA competence. IMPACT: This international consensus-based expert statement provides content on a curriculum for the less invasive surfactant administration procedure (LISA-CUR) that may be partnered with existing evidence-based strategies to optimize and standardize LISA training in the future. This international consensus-based expert statement also provides content on an assessment tool for the LISA procedure (LISA-AT) that can help to evaluate competence in LISA operators. The proposed LISA-AT enables standardized, continuous feedback and assessment until achieving proficiency.

A multicenter, randomized controlled, non-inferiority trial, comparing nasal continuous positive airway pressure with nasal intermittent positive pressure ventilation as primary support before minimally invasive surfactant administration for preterm infants with respiratory distress syndrome (the NIV-MISA-RDS trial): Study protocol.

Background: Non-invasive ventilation (NIV) treatment has been developed to minimize lung damage and to avoid invasive mechanical ventilation (IMV) in preterm infants, especially in those with a gestational age of <30 weeks. Our hypothesis is that for preterm infants <30 weeks with potential to develop respiratory distress syndrome (RDS), nasal continuous positive airway pressure (NCPAP) is non-inferior to the nasal intermittent positive pressure ventilation (NIPPV) as primary respiratory support before minimal invasive surfactant administration (MISA). Methods and design: The NIV-MISA-RDS trial is planned as an unblinded, multicenter, randomized, non-inferiority trial at 14 tertiary neonatal intensive care units (NICUs) in China. Eligible infants are preterm infants of 24-29+6 weeks of gestational age who have spontaneous breaths at birth and require primary NIV support for RDS. Infants are randomized 1:1 to treatment with either NCPAP or NIPPV once admitted into NICUs. If an infant presents progressively aggravated respiratory distress and is clinically diagnosed as having RDS, pulmonary surfactant will be supplemented by MISA in the first 2 h of life. The primary outcome is NIV treatment failure within 72 h after birth. With a specified non-inferiority margin of 10%, using a two-sided 95% CI and 80% power, the study requires 480 infants per group (in total 960 infants). Discussion: Current evidence shows that NIV and MISA may be the most effective strategy for minimizing IMV in preterm infants with RDS. However, there are few large randomized controlled trials to compare the effectiveness of NCPAP and NIPPV as the primary respiratory support after birth and before surfactant administration. We will conduct this trial to test the hypothesis that NCPAP is not inferior to NIPPV as the initial respiratory support in reducing the use of IMV in premature infants who have spontaneous breaths after birth and who do not require intubation in the first 2 h after birth. The study will provide clinical data for the selection of the initial non-invasive ventilation mode in preterm infants with a gestational age of <30 weeks with spontaneous breaths after birth. Clinical trial registration: https://register.clinicaltrials.gov, identifier: NCT05137340.

Status and Influencing Factors of Parenteral Nutrition Practice for Late Preterm Infants in China.

Objectives: To explore the status of parental nutrition practice of hospitalized late preterm infants and the factors influencing the clinical prescription. Methods: A multi-center, prospective cohort study was conducted during October 2015 to October 2017. Infants born after 34 weeks and before 37 weeks were enrolled from twenty-five hospitals in the Beijing area of China. Data of enteral and parenteral nutrition were collected. Results: A total of 1,463 late preterm infants were enrolled in this study, 53.9% of infants were supported by parenteral nutrition. Over 60% of 34 weeks' infants were on parenteral nutrition during the 2nd to the 4th day. Logistic regression analysis showed that gestational age(GA) (OR = 0.69, 95%CI 0.58-0.81), birth weight (OR = 0.41, 95%CI 0.26-0.65), hypoglycemia (OR = 2.77, 95%CI 1.90-4.04), small for gestational age (SGA) (OR = 2.18, 95%CI 1.34-3.55), feeding intolerance (OR = 6.41, 95%CI 1.90-21.59), neonatal respiratory distress syndrome (NRDS) (OR = 2.16, 95%CI 1.12-4.18), neonatal infection(OR = 1.56 95%CI 1.16-2.10), and slow enteral nutrition advancement rate (OR = 0.92, 95%CI 0.90-0.95) were factors influencing the administration of parenteral nutrition. Conclusion: Over half of hospitalized late preterm infants were prescribed with parenteral nutrition. Infants with lower GA, lower birth weight, diagnosed with hypoglycemia, SGA, feeding intolerance, NRDS, neonatal infection, or a slower rate of enteral nutrition advancement had a higher likelihood of receiving parenteral nutrition.

[Association between time of birth and resuscitation outcomes in extremely preterm infants].

OBJECTIVE: To study whether there are differences in the resuscitation process and early outcomes between the extremely preterm infants delivered on off-hours (6 pm to 8 am of working days, weekends, and national holidays) and those delivered on working hours. METHODS: A retrospective analysis was performed on the medical data of extremely preterm infants who were born in the Peking University Third Hospital from January 1, 2010 to December 31, 2020 and transferred to the neonatal intensive care unit (NICU). According to the time of birth, they were divided into two groups:working hours (n=77) and off-hours (n=98). The resuscitation process and early outcomes were compared between the two groups. RESULTS: Compared with the working hours group, the off-hours group had a significantly lower proportion of infants with the use of full-dose dexamethasone before delivery (P < 0.05) and a significantly higher proportion of infants with a 1-minute Apgar score of < 7, positive pressure ventilation, or tracheal intubation (P < 0.05). The incidence rates of neonatal respiratory distress syndrome and intrauterine pneumonia in the off-hours group were significantly higher than those in the working hours group (P < 0.05). CONCLUSIONS: Extremely preterm infants delivered on off-hours tend to have a low Apgar score at 1 minute after birth, with a higher proportion of infants requiring positive pressure ventilation or tracheal intubation during resuscitation than those delivered on working hours, and they tend to develop neonatal respiratory distress syndrome and intrauterine pneumonia. This suggests that it is important to make adequate preparations in terms of personnel and supplies for resuscitation of extremely preterm infants after birth and that NICUs should develop a detailed management plan for extremely preterm infants at each period of time before, during, and after birth.

Screening of Serum Alkaline Phosphatase and Phosphate Helps Early Detection of Metabolic Bone Disease in Extremely Low Birth Weight Infants.

Background: Extremely low birth weight (ELBW, <1,000 g) infants have a high risk of metabolic bone disease (MBD). Because of the late appearance of radiological signs, diagnosis of MBD in ELBW infants might be delayed, and its prevalence underestimated in this group of patients. This study adopted serial screening of serum alkaline phosphatase (ALP) and phosphate (P) of ELBW infants to determine whether such screening is helpful for the early detection of MBD. Materials and Methods: We performed a retrospective study of preterm infants with a gestational age ≤ 31 weeks and birth weight <1,000 g. MBD was absent (ALP ≤500 IU/L), mild (ALP >500 IU/L, P ≥4.5 mg/dL), and severe (ALP >500 IU/L, P <4.5 mg/dL); MBD was divided into early MBD (≤4 weeks after birth) and late MBD (>4 weeks after birth) according to the time of onset. Results: A total of 142 ELBW infants were included, with a median gestational age of 28.1 (26.5-29.7) weeks and a median birth weight of 875 (818-950) g. Seventy-three cases of MBD were diagnosed, and the total prevalence was 51.4% (mild MBD, 10.6%; and severe MBD, 40.8%). Male sex, breastfeeding, and sepsis would increase the risk of severe MBD. Most MBD in ELBW infants occurred at 3-4 weeks after birth. Sixty-two percent (45/73) of infants were diagnosed as having early MBD, which are diagnosed earlier than late MBD [24 (21-26) vs. 39 (36-41), t = -7.161; P < 0.001]. Male sex [odds ratio (OR), 2.86; 95% confidence interval (CI), 1.07-7.64; P = 0.036], initial high ALP levels (OR, 1.02; 95% CI, 1.01-1.03; P < 0.001), and breastfeeding (OR, 5.97; 95% CI, 1.01-25.12; P = 0.049) are independent risk factors for the development of early MBD. Conclusion: The risk of MBD among ELBW infants is very high. Most cases occurred early and were severe. Male sex, initial high ALP levels, and breastfeeding are closely related to the increased risk of early MBD. Serial screening of serum ALP and P helps early detection of MBD; it is recommended to start biochemical screening for ELBW infants 2 weeks after birth and monitor their biochemical markers weekly.

Mortality and Morbidity of Infants Born Extremely Preterm at Tertiary Medical Centers in China From 2010 to 2019.

Importance: Extreme prematurity is associated with a substantial burden on health care systems worldwide. However, little is known about the prognosis of infants born extremely preterm in developing countries, such as China. Objective: To describe survival and major morbidity among infants born extremely preterm in China over the past decade. Design, Setting, and Participants: This retrospective cohort study was conducted from January 1, 2010, through December 31, 2019. Included individuals were infants with gestational age less than 28 weeks discharged from 1 of 68 neonatal intensive care units located in 31 provinces in China. Data were analyzed from August through October 2020. Exposure: Extremely preterm birth. Main Outcomes and Measures: Survival to discharge and major morbidity (ie, bronchopulmonary dysplasia, grades III-IV intraventricular hemorrhage, white matter injury, stage II-III necrotizing enterocolitis, sepsis, or severe retinopathy of prematurity) were measured. Results: Among 8514 eligible infants, 5295 (62.2%) were male and 116 infants (2.0%) were small for gestational age (SGA). Overall, 5302 infants (62.3%) survived to discharge. The survival rate was 1 of 21 infants (4.8%) at 22 weeks, 13 of 71 infants (18.3%) at 23 weeks, 144 of 408 infants (35.3%) at 24 weeks, 480 of 987 infants (48.6%) at 25 weeks, 1423 of 2331 infants (61.0%) at 26 weeks, and 3241 of 4692 infants (69.1%) at 27 weeks. Survival increased from 136 of 241 infants (56.4%; 95% CI, 50.1%-62.7%) in 2010 to 1110 of 1633 infants (68.0%; 95% CI, 65.7%-70.2%) in 2019 for infants born at 24 to 27 weeks (mean difference, 11.5%; 95% CI, 4.9%-18.2%; P < .001), without a significant change for infants born at less than 24 weeks. Major morbidity was found in 5999 of 8281 infants overall, for a rate of 72.4%, which increased from 116 of 223 infants (52.0%; 95% CI, 45.4%-58.6%) to 1363 of 1656 infants (82.3%; 95% CI, 80.5%-84.1%) from 2010 to 2019 (mean difference, 30.3%; 95% CI, 23.5%-37.1%, P < .001). Regional variations in survival were identified, with an almost 2-fold increase (1.94-fold; 95% CI, 1.66-2.27; P < .001) from 188 of 474 infants (39.7%) in northwest China to 887 of 1153 infants (76.9%) in north China. Gestational age (adjusted risk ratio [aRR], 1.084; 95% CI, 1.063-1.105; P < .001), birth weight (aRR, 1.028; 95% CI, 1.020-1.036; P < .001), premature rupture of membranes (aRR, 1.025; 95% CI, 1.002-1.048; P = .03), and antenatal steroids (aRR, 1.029; 95% CI, 1.004-1.055; P = .02) were associated with improved survival, while being born SGA (aRR, 0.801; 95% CI, 0.679-0.945; P = .01), being male (aRR, 0.975; 95% CI, 0.954-0.997; P = .02), multiple birth (aRR, 0.955; 95% CI, 0.929-0.982; P = .001), having a mother with gestational diabetes (aRR, 0.946; 95% CI, 0.913-0.981; P = .002), and low Apgar score (aRR, 0.951; 95% CI, 0.925-0.977; P < .001) were found to be risk factors associated with decreased chances of survival. Conclusions and Relevance: This study found that infants born extremely preterm were at increased risk of mortality and morbidity in China, with a survival rate that improved over time and a major morbidity rate that increased. These findings suggest that more active and effective treatment strategies are needed, especially for infants born at gestational age 25 to 27 weeks.

[A clinical analysis of hypothyroidism in very low birth weight/extremely low birth weight infants].

OBJECTIVE: To study the risk factors and treatment outcome of hypothyroidism in very low birth weight/extremely low birth weight (VLBW/ELBW) infants. METHODS: The VLBW/ELBW infants who were diagnosed with hypothyroidism from September 2018 to December 2019 were enrolled as the case group (n=29). The children with normal thyroid function, matched at a ratio of 1 : 3, were enrolled as the control group (n=87). Clinical features were compared between the two groups. The correlation of thyroid function with gestational age and birth weight and the risk factors for hypothyroidism were analyzed. RESULTS: A total of 162 VLBW/ELBW infants who met the inclusion criteria were enrolled, with 29 infants in the case group (an incidence rate of hypothyroidism of 17.9%). The lower the birth weight, the higher the incidence rate of hypothyroidism (P<0.05). Triiodothyronine (T3) and free T3 were positively correlated with gestational age (P<0.05). T3 and free thyroxine were positively correlated with birth weight (P<0.05). Small for gestational age, multiple birth, maternal age ≥ 35 years, and use of dopamine were independent risk factors for hypothyroidism (P<0.05). In the case group, 16 infants were treated with levothyroxine (5-10 µg/kg daily), and the thyroid function returned to normal after 2 weeks of treatment. CONCLUSIONS: There is a high incidence rate of hypothyroidism in VLBW/ELBW infants. Small for gestational age, multiple birth, advanced maternal age, and use of dopamine are risk factors for hypothyroidism. The infants treated with levothyroxine should be followed up regularly to ensure an appropriate dose.

Minimally Invasive Surfactant Administration for the Treatment of Neonatal Respiratory Distress Syndrome: A Multicenter Randomized Study in China.

Background/Aims: Nasal continuous positive airway pressure (nCPAP) was recommended as the initial respiratory support for spontaneous breathing in infants with very low birth weight and neonatal respiratory distress syndrome (NRDS). Less invasive surfactant administration (LISA) and minimally invasive surfactant therapy (MIST) have been reported to reduce the incidence of bronchopulmonary dysplasia (BPD). This study aimed to explore the applicability of minimally invasive surfactant administration (MISA) in China. Materials and Methods: MISA was a randomized controlled study conducted at eight level III neonatal intensive care units (NICUs) in China. Spontaneously breathing infants born at 25+0 to 31+6 weeks' gestation who progressively developed respiratory distress during the first 6 h after birth were randomly assigned to receive MISA or endotracheal intubation surfactant administration (EISA). The primary outcome was the difference in the morbidity of BPD between two groups of infants with MISA and EISA at 36 weeks corrected gestational age. Results: Demographic and clinical characteristics of the 151 infants in the MISA group were similar to the 147 infants in the EISA group. The comparison showed no clear benefits in the MISA group in the incidence of BPD, while infants from the EISA group had higher rates of patent ductus arteriosus (PDA) (60.5 vs. 41.1%, p = 0.001). The duration of surfactant infusion and the total time of surfactant administration in the MISA group were significantly longer than in the EISA group. A slightly increased heart rate was noted 1 h post surfactant administration in the EISA group. In subgroup analysis, the comparison of 51 smaller (<30 weeks) preterm infants, named MISAs (n = 31) and EISAs (n = 20), showed a significant reduction of BPD (29.0 vs. 70.0%, p = 0.004) and PDA (29.0 vs. 65.0%, p = 0.011). In the subgroup analysis of blood gas, arterial oxygen saturation (SaO2) value at 1 and 12 h and partial pressure of arterial oxygen (PaO2) at 12 h were all higher in the EISA group compared to the MISA group. Conclusion: MISA had no clear benefit on the incidence of BPD, but it was related to a reduction in PDA. It is an appropriate therapy for spontaneous breathing in infants with extremely low birth weight and NRDS.

[Risk factors for minimally invasive surfactant administration failure in preterm infants with respiratory distress syndrome].

OBJECTIVE: To identify risk factors for minimally invasive surfactant administration (MISA) failure in the treatment of preterm infants with respiratory distress syndrome (RDS) and the influence of MISA failure on neonatal outcome. METHODS: A retrospective analysis was performed for the clinical data of 148 preterm infants with a gestational age of ≤32 weeks and a clinical diagnosis of RDS, who were admitted to the neonatal intensive care unit of eight tertiary hospitals in Beijing, Tianjin and Hebei Province from July 1, 2017 to December 31, 2018 and were treated with MISA (bovine pulmonary surfactant, PS). According to whether MISA failure (defined as the need for mechanical ventilation within 72 hours after MISA) was observed, the infants were divided into two groups: MISA failure group (n=16) and MISA success (n=132). A logistic regression analysis was used to investigate the risk factors for MISA failure and its influence on neonatal outcome. RESULTS: The MISA failure rate was 10.8% (16/148). The logistic regression analysis showed that a high incidence rate of grade >II RDS before PS administration, low mean arterial pressure and high pulse pressure before administration, a low dose of initial PS administration, and long injection time and operation time were the risk factors for MISA failure (OR=5.983, 1.210, 1.183, 1.055, 1.036, and 1.058 respectively, P<0.05). After the control for the above risk factors, the logistic regression analysis showed that the MISA failure group had a significantly higher incidence rate of bronchopulmonary dysplasia (BPD) (OR=8.537, P<0.05). CONCLUSIONS: A high grade of RDS, a low mean arterial pressure, and a high pulse pressure before administration are independent risk factors for MISA failure, and a low dose of initial PS administration, a long injection time, and a long operation time may increase the risk of MISA failure. MISA failure may increase the incidence rate of BPD in preterm infants.

[Prognosis of bronchopulmonary dysplasia in preterm infants: a follow-up during infancy].

OBJECTIVE: To investigate the physical development, incidence of common respiratory diseases, and motor development during infancy in preterm infants with bronchopulmonary dysplasia (BPD). METHODS: A retrospective analysis was performed on the clinical features and infantile outcomes of preterm infants with BPD who were admitted to the neonatal intensive care unit between January 2012 and December 2015. Preterm infants without BPD were used as controls who were admitted to the neonatal intensive care unit during the same period and had similar gestational age and birth weight. Physical development, number of hospital stays, the incidences of pneumonia and wheezing, and motor development during infancy were compared between the two groups. RESULTS: Compared with the control group, BPD infants had a significantly higher incidence of extrauterine growth retardation at discharge (48% vs 41%; P<0.05); BPD infants were more susceptible to pneumonia, wheezing, eczema and rhinitis; BDP infants also had a significantly higher number of readmissions due to respiratory tract infection (P<0.05). BPD infants had a significantly smaller head circumference than the control group at corrected ages of 3, 6, and 12 months (P<0.05). BPD infants had significantly delayed gross, fine, and overall motor development than the control group at corrected ages of 6 and 9 months (P<0.05). CONCLUSIONS: Infants with BPD are susceptible to extrauterine growth retardation at discharge. Their head circumference growth is relatively slow. They are susceptible to pneumonia and wheezing during infancy. Moreover, they have delayed motor development when compared with those without BPD at corrected ages of 6 and 9 months.

Different Effects of Premature Infant Formula and Breast Milk on Intestinal Microecological Development in Premature Infants.

Intestinal microecology has been shown to participate in the pathogenesis of many diseases through different pathways, and the intestinal microecology of premature infants is significantly different from full-term infants. Intestinal microecology in premature infants is affected by various factors such as gestational age, diet, antibiotic use. However, there are few studies focus on the effects of diet on intestinal microecological development in premature infants. This study explored the different effects of the formula milk (FM) and breast milk (BM) for the development of intestinal microecology in premature infants. The results showed that BM feeding increases the alpha diversity of the intestinal flora, however, FM feeding contributes to the increase in short-chain fatty acids (SCFAs) in the gut of preterm infants. The growth environment has an important influence on the ß diversity of intestinal microecology, the genomic function, and the evolution of intestinal microecology in premature infants. The intestinal microecology in premature infants is significantly associated with gestational age and weight gain. This study explored the effects of feeding methods and growth environment on intestinal microecology in premature infants, and provided a basis for promoting the healthy development of premature infants.

[Persistent hypertension for two months in a preterm infant].

A boy aged 2 months (born at 36 weeks of gestation) was admitted due to cough and dyspnea. After admission, he was found to have persistent hypertension, proteinuria, and persistent convulsion, and imaging examination showed extensive calcification of the aorta and major branches and stenosis of local lumens of the abdominal aorta and the right renal artery with increased blood flow velocity. The boy was admitted during the neonatal period due to wet lung and pulmonary arterial hypertension and was found to have hypertension and proteinuria. High-throughput whole-exome sequencing was performed and found two compound heterozygous mutations in the ENPP1 gene from his parents, c.130C>T (p.Q44X) and c.1112A>T (p.Y371F). c.130C>T was a nonsense mutation, which could cause partial deletion of protein from 44 amino acids, and was defined as a primary pathogenic mutation. c.1112A>T was a missense mutation which had been reported as a pathogenic mutation associated with idiopathic infantile arterial calcification (IIAC). Therefore, he was diagnosed with IIAC. He was given phosphonate drugs, antihypertensive drugs, anticonvulsion treatment, and respiratory support. Blood pressure was maintained at the upper limit of normal value. There was no deterioration of arterial calcification. It is concluded that IIAC should be considered for infants with persistent hypertension and extensive vascular calcification, and imaging and genetic examinations should be performed as early as possible to make a confirmed diagnosis.

Structure analysis of transposons carrying the aac(6')-aph(2″) gene in Enterococcus faecalis isolated in Beijing, China, and comparison of their transfer efficiency.

Transfer of aac(6')-aph(2″) transposons mediating high-level gentamicin resistance (HLGR) in Enterococcus faecalis is a serious problem in the clinic. However, factors affecting the transfer of aac(6')-aph(2″) have not yet been elucidated. The current study aimed to examine the genetic and molecular basis of HLGR in E. faecalis strains isolated in Beijing (China) and to clarify the relationship between transfer efficiency of aac(6')-aph(2″) transposons and the transposon structure/location. A total of five transposon structures were identified by PCR mapping of the corresponding transposon regions, including a Tn5281-like non-truncated transposon and four truncated transposons. A plasmid location study of aac(6')-aph(2″) by Southern blot following S1-PFGE and filter mating conjugation experiments demonstrated that plasmid location rates correlated with conjugation-positive rates. Chromosome walking to identify the sequence upstream of a representative type III truncated transposon found a truncated aph(2″)-Ia region, and further PCR analysis of this region among strains from different groups revealed similar a positive rate trend as the transposon plasmid location rate and conjugation-positive rate. In conclusion, aac(6')-aph(2″) transposons were of different structures in E. faecalis strains from Beijing, with two new transposon structures that have not been reported elsewhere. Presence of the truncated aph(2″)-Ia region upstream of some truncated transposons suggests recombination between aminoglycoside-modifying enzyme genes. Possible links exist among plasmid location, conjugation and the presence of truncated aph(2″)-Ia upstream of the transposon.

[A survey of pubertal development in children born with assisted reproductive technology].

OBJECTIVE: To investigate the status of pubertal development in children born with assisted reproductive technology (ART). METHODS: A retrospective analysis was performed on the pubertal development data of children born with ART in Peking University Third Hospital from 1994 to 2003 (ART group). The data in the cross-sectional study "Reports on the Physical Fitness and Health Research of Chinese School Students in 2010" were used as a control. The age at menarche and the age at spermarche were compared between the two groups. The status of pubertal development in the overweight and obese children in the ART group was evaluated to investigate the correlation between pubertal development and body mass index (BMI). RESULTS: A total of 200 children born with ART were enrolled in this study, and 72 of them (41 males and 31 females) completed the survey (response rate=36.0%). In the ART group, the mean age at spermarche and the mean age at menarche were 13.9 years (95%CI: 13.7-14.3 years) and 12.2 years (95%CI: 11.8-12.6 years), respectively. There were no significant differences in the age at spermarche and the age at menarche between the ART and control groups (P>0.05). In the ART group, there were no significant differences in the age at spermarche and the age at menarche between the overweight and obese children and the normal weight children (P>0.05). There were also no significant differences in overweight rate and obesity rate between the children in the ART group and the adolescents in Beijing (P>0.05). In the ART group, there was no significant correlation between the age at spermarche or menarche and BMI (P>0.05). CONCLUSIONS: No delayed or precocious puberty is observed in children born with ART. This is consistent with the normal control data. And there is no significant correlation between pubertal development and BMI in children born with ART.

Paenibacillus populi sp. nov., a novel bacterium isolated from the rhizosphere of Populus alba.

A novel aerobic bacterium, designated strain LAM0705(T), was isolated from the rhizosphere of Populus alba in the Peking University Third Hospital. Cells of strain LAM0705(T) were observed to be Gram-stain positive, motile, spore-forming and rod-shaped. The optimal temperature and pH for growth were found to be 30 °C and pH 7.5, respectively. Strain LAM0705(T) was found to be able to grow in the presence 0-5 % NaCl (w/v) (optimum 1.0 %). The major fatty acids of strain LAM0705(T) were identified as anteiso-C15:0, C16:0 and iso-C16:0. The dominant polar lipids were found to consist of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The cell wall peptidoglycan of strain LAM0705(T) was found to contain meso-diaminopimelic acid. The predominant menaquinone was identified as MK-7. The G+C content of genomic DNA was found to be 48 mol% when determined by the T m method. The 16S rRNA gene sequence similarity analysis indicated that strain LAM0705(T) is closely related to Paenibacillus agaridevorans DSM 1355(T) and Paenibacillus thailandensis KCTC 13043(T) with 97.8 and 96.1 % sequence similarity, respectively. The DNA-DNA hybridization value between strain LAM0705(T) and P. agaridevorans DSM 1355(T) was 47 ± 0.8 %. On the basis of its phenotypic, phylogenetic and chemotaxonomic characteristics, strain LAM0705(T) is concluded to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus populi sp. nov. is proposed. The type strain is LAM0705(T) (=ACCC 06427(T) = JCM 19843(T)).