[Current status of pubertal sexual characteristics development of 2 704 girls aged 6-18 years in Tongzhou District of Beijing]

Objective: To understand the current status of pubertal sexual characteristics development of girls aged 6-18 years in Tongzhou District of Beijing and to compare the differences in sexual characteristics development among girls characterized as thin, normal, overweight, and obese. Methods: A cross-sectional survey was conducted among 2 844 girls aged 6-18 years in Tongzhou District of Beijing from September 2022 to July 2023. The developmental stages of breast and pubic hair were assessed on site, and menarche status was inquired. Weight and height were measured. The girls were subsequently characterized into thin, normal, overweight and obese groups. Basic information (including family and personal history) was obtained through questionnaires. Probit probability unit regression was applied to calculate the age of each Tanner stage of sexual characteristics development and the age of menarche. The χ2 test was applied to compare the counting data between two or multiple groups. Results: A total of 2 844 girls were surveyed and 2 704 girls met the inclusion criteria, resulting in a valid response rate of 95.1%. Among these girls, 1 105 (40.9%) were aged 6-9 years, 1 053 (38.9%) were aged 10-13 years, and 546 (20.2%) were aged 14-18 years. The of height-for-age Z-score (HAZ), weight-for-age Z-score (WAZ), and body mass index-for-age Z-score (BAZ) were 0.46(-0.23,1.16), 0.69(-0.16,1.67), and 0.67(-0.27,1.73) respectively. The prevalences of thin, overweight, and obesity were respectively 1.7% (45/2 704), 17.3% (467/2 704), and 19.9% (538/2 704), respectively. There were 45 girls in the thin group, 1 654 girls in the normal weight group, 1 005 girls in the overweight and obesity group. The age of Tanner stage breast 2 (B2), Tanner stage pubic hair 2 (P2), and menarche was 9.0 (95%CI 8.9-9.1), 10.5 (95%CI 10.4-10.6), and 11.4 (95%CI 11.3-1.5) years, respectively. The current status of breast and pubic hair maturity in girls with pubertal development shows that 64.6% (1 211/1 874) of these girls had breast development preceding pubic hair development, 32.4% (607/1 874) had concurrent breast and pubic hair development, and 3.0% (56/1 874) had pubic hairs development preceding breast development. The interval age between B2 and B5 was 4.7 (95%CI 4.6-4.8) years, between P2 and P5 was 4.5 (95%CI 4.4-4.6) years, and between B2 and menarche was 2.4 (95%CI 2.3-2.5) years. The ages of sexual characteristics development in overweight and obese groups were earlier than that in normal and thin groups. The ages of B2 in thin, normal, overweight, and obese groups were 10.0 (95%CI 9.5-10.6), 9.3 (95%CI 9.2-9.4), and 8.6 (95%CI 8.4-8.7) years, respectively. The age of menarche in thin, normal, overweight, and obese groups were 13.1 (95%CI 12.4-13.7), 11.6 (95%CI 11.4-11.7), and 11.1 (95%CI 11.0-11.2) years, respectively. The interval ages between B2 and B5 and between P2 and P5 was 4.5 and 4.1 years, respectively in the overweight and obese groups, and those in normal group and thin group was 4.7 and 4.5 years, 4.6 and 4.7 years, respectively. Conclusions: The ages of sexual characteristics development and menarche tend in Tongzhou District of Beijing to be earlier than that being reported of Beijing's survey 20 years ago. Girls characterized as overweight and obese not only start puberty at an earlier age than girls of normal weight, but also have a shorter developmental process.

[Updated growth standards for Chinese children under 7 years of age]

Objective: To construct growth standards for Chinese children under 7 years of age. Methods: Cross-sectional study design based on national representative data on children's growth and development in 2015 was used. Stratified cluster sampling method was used. A total of 83 628 healthy children aged 0-<7 years from 9 cities, including Beijing, Harbin, Xi'an, Shanghai, Nanjing, Wuhan, Guangzhou, Fuzhou, and Kunming, were investigated from June to November 2015, excluding those with adverse conditions that may impact the establishment of the growth standards. Weight, length (height) and head circumference were measured using unified measurement tools and measurement methods. The Lambda-Mu-Sigma method was employed to establish percentile and standard deviation score reference values of weight-for-age, length (height)-for-age, head circumference-for-age, weight-for-length (height) and body mass index (BMI)-for-age of the study population. The standard deviation score curves of the new-established growth standards were compared with the 2009 reference standards. Results: Reference values of percentile (P3, P10, P25, P50, P75, P90, P97) and standard deviation score (-3, -2, -1, 0,+1,+2,+3) of weight-for-age, length (height)-for-age, head circumference-for-age, weight-for-length (height) and BMI-for-age were obtained. Compared with the 2009 growth standards, the difference of weight at P50 was -0.1-0.4 kg, the difference of length (height) at P50 was 0.1-1.3 cm, the difference of head circumference at P50 was -0.2-0.2 cm, the difference of weight for length (height) at P50 was -0.2-0.5 kg, and the difference of BMI at P50 was -0.2-0.2 kg/m2. The main differences were as follows: weight for girls aged 5.0-<7.0 years was 0.4-0.6 kg higher at +2 s, height for boys and girls aged 2.0-<7.0 years was 0.4-1.4 cm higher at -2 s, and BMI for boys and girls aged 5.0-<7.0 years was 0.1-0.3 kg/m2 higher at +2 s than the 2009 reference standards. Conclusion: The newly established growth standards for Chinese children under 7 years of age that have achieved a minor revision to the 2009 reference standards, are recommended for nationwide use in growth monitoring and nutritional assessment.

[Clinical characteristics of COVID-19 Omicron variant infection in children with allergic diseases]

Objective: To analyze the clinical characteristics of infection of COVID-19 Omicron variants in children with allergic diseases. Methods: This was a cross-sectional retrospective study. A total of 657 pediatric patients with allergic diseases aged between 0-17 years confirmed with COVID-19 infection were enrolled from the Children's Hospital affiliated to Capital Institute of Pediatrics from January to March 2023. The median age was 6.6(4.7,9.9) years, with 443 males (67.4%) and 214 females (32.6%). Demographic data, vaccination status, clinical manifestations, therapeutic drugs, and other data were collected. The patients were then divided into different groups according to the age, type of allergic diseases and vaccination status, and their clinical characteristics were compared. Results: A total of 657 children with allergic diseases were included in this study, among them 568 with asthma. Fever is the most common symptoms after COVID-19 infection (627/657, 95.4%), and 509 children (77.5%) with high fever. Cough was observed in 446 (67.9%) and fatigue in 167 (25.4%) cases.10 cases (1.5%) were diagnosed as pneumonia. The proportion of pharyngalgia(22%,84/382, χ2=19.847, P<0.01), fatigue (31.7%, 121/382,χ2=23.831, P<0.01), headache(34.6%, 132/382,χ2=57.598, P<0.01), muscle joint pain(16.0%, 61/382,χ2=22.289, P<0.01) and vomiting(11.0%, 42/382,χ2=12.756, P<0.01) were highest in the>6 years group. Children younger than 3 years had the lowest proportion of runny nose(8.8%, 5/57,χ2=8.411, P<0.01), cough(45.6%, 26/57,χ2=6.287, P<0.05) and expectoration(7.0%, 4/57,χ2=5.950, P<0.05). 62.8%(137/218) of the patients in 3-6 year group had the highest rate of cough(χ2=6.287, P<0.05), with a higher proportion of wheezing (10.1%, 22/218). Cough and/or wheezing symptoms were most quickly relieved in the 6 year old group, who had a highest proportion of 68.8%(260/382) in duration of respiratory symptoms within 1 week compared with 52.2% (114/218)of 3-6 years group and 41.2% (22/57)of<3 year group, respectively(χ2=23.166, P<0.01). The asthma group had a significant higher proportion of cough(59.7% vs 41.6%, χ2=10.310, P<0.01), wheezing (8.5% vs 0.0%, χ2=8.114, P<0.01) and expectoration (19.2% vs 7.9%, χ2=10.310, P<0.01) than that of non-asthma group. Besides, patients with cough and/or wheezing in the asthma group had more impact on exercise and sleep (16.1% vs 0, χ2=5.436, P<0.05) and a longer duration over 4 weeks (25.1% vs 3.7%, χ2=6.244, P<0.05). Conclusions: The most common symptoms in children with allergy infected with COVID-19 Omicron variant were fever and cough. Children under 3 years of age had relatively fewer respiratory symptoms while those with asthma or aged 3-6 years were more likely to have cough and wheezing and longer duration of symptoms. The data suggested that the prevention and management of COVID-19 should be strengthened in children with allergy.

[Alertness and task processing speed impairment status and influencing factors of young-middle aged men with obstructive sleep apnea hypopnea syndrome]

Objective: To investigate the alertness and task processing speed impairment status in young-mild aged men with obstructive sleep apnea hypopnea syndrome (OSAHS), and analyze its influencing factors. Methods: This prospective study recruited 251 snoring patients aged 18 to 59 (38.9±7.6) years in the Sleep Center of the Second Affiliated Hospital of Soochow University from July 2020 to September 2021 and all patients were diagnosed by polysomnography (PSG). Clinical information, Epworth Sleepiness Scale (ESS) and PSG date were collected. All patients were assessed with the Montreal Cognitive Assessment (MoCA) questionnaires, Mini-mental State Examination (MMSE) and Computerized Neurocognitive Assessment System which includes the reaction time of Motor Screening Task (MOT) for alertness, the reaction time of pattern recognition memory (PRM), spatial span (SSP) and spatial working memory (SWM) for task processing speed. Based on AHI tertiles, all patients were divided into Q1 group (AHI<15 times/h, n=79), Q2 group (15 times/h≤AHI<45 times/h, n=88), and Q3 group (AHI≥45 times/h, n=84). The characteristics of clinical information, ESS, PSG parameters and cognitive scores among three groups were compared. Multiple linear stepwise regression was conducted to analyze the influencing factors of cognitive impairment. Results: There were no statistically significant differences in age, years of education, history of smoking and drinking, and past disease history (except for the prevalence of hypertension) among the 3 groups (P>0.05). There were statistically significant among-group differences in the body mass index (BMI), ESS, prevalence of hypertension and complaints of daytime sleepiness (P<0.05). Compared with Q1 and Q2 group, the arousal index (ArI), oxygen desaturation index (ODI),the proportion of non-rapid eye movement phase 1 and 2 (N1+N2) and percentage of total sleep time with oxygen saturation level<90% (TS90) of Q3 group were higher (all P<0.05). In the cognitive assessment, there was no statistically significant difference in the MoCA total and individual scores and MMSE scores among the three groups (P>0.05). Compared with the Q1 group, the task processing speed and alertness were worse in Q3 group, as shown by slower PRM immediate and delayed reaction time, SSP reaction time and MOT reaction time (all P<0.05). The total time of SWM in Q2 group was slower than that in Q1 group (P<0.05). Multiple linear stepwise regression showed that years of education (β=-40.182, 95%CI:-69.847--10.517), ODI (β=3.539, 95%CI: 0.600-6.478) were the risk factors of PRM immediate reaction time. Age(β=13.303,95%CI: 2.487-24.119), years of education(β=-32.329, 95%CI:-63.162--1.497), ODI (β=4.515, 95%CI: 1.623-7.407) were the risk factors of PRM delayed reaction time. ODI was the risk factor of SSP reaction time (β=1.258, 95%CI: 0.379-2.137). TS90 was the risk factor of MOT reaction time (β=1.796, 95%CI: 0.664-2.928). Conclusions: The early cognitive impairment in young-mild aged OSAHS patients was manifested in decreased alertness and task processing speed, and intermittent nocturnal hypoxia was its influencing factor in addition to age and years of education.

[Reference values and growth curves of length for weight and head circumference for weight among Chinese newborns]

Objective: To establish the reference values and growth curves of length for weight and head circumference for weight among Chinese newborns in order to provide a reference for the assessment of body proportionality at birth. Methods: A cross-sectional design was applied. A total of 24 375 singleton live birth newborns with gestational ages at birth of 24⁺⁰ to 42⁺⁶ weeks were recruited from June 2015 to November 2018 from 13 cities including Beijing, Harbin, Xi'an, Shanghai, Nanjing, Wuhan, Guangzhou, Fuzhou, Kunming, Tianjin, Shenyang, Changsha, and Shenzhen, excluding those with maternal or newborn conditions that may impact the establishment of the reference values. The generalized additive model for location, scale, and shape was employed to establish reference values in terms of percentile and growth curves of length for weight and head circumference for weight for male and female newborns. The random forest machine learning method was employed to analyze the importance of variables between the established reference values in this study and the previous published weight/length, body mass index (BMI), ponderal index (PI), weight/head circumference, length/head circumference in the assessment of symmetrical and asymmetrical small for gestational age (SGA) newborns. Results: A total of 24 375 newborns with 13 197 male infants (preterm birth 7 042 infants and term birth 6 155 infants) and 11 178 female infants (preterm birth 5 222 infants and term birth 5 956 infants) were included in this study. The reference values in terms of percentile (P₃, P₁₀, P₂₅, P₅₀, P₇₅, P₉₀, P₉₇) and growth curves of length for weight and head circumference for weight were obtained for male and female newborns with gestational ages of 24⁺⁰ to 42⁺⁶ weeks. The median birth lengths corresponding to the birth weights of 1 500, 2 500, 3 000, and 4 000 g were 40.4, 47.0, 49.3 and 52.1 cm for males and 40.4, 47.0, 49.2, and 51.8 cm for females, respectively; the median birth head circumferences were 28.4, 32.0, 33.2 and 35.2 cm for males and 28.4, 32.0, 33.1, and 35.1 cm for females, respectively. The differences of length for weight between males and females were minimum, with the difference range of -0.3 to 0.3 cm at P₅₀; the differences of head circumference for weight between males and females were minimum, with the difference range of 0 to 0.2 cm at P₅₀. Based on the match between birth length and birth weight for classifying symmetrical and asymmetrical SGA, length for weight and PI contributed the most, accounting for 0.32 and 0.25, respectively; based on the match between birth head circumference and birth weight, head circumference for weight and weight/head circumference contributed the most, accounting for 0.55 and 0.12, respectively; based on the match between birth length or head circumference with birth weight, head circumference for weight and length for weight contributed the most, accounting for 0.26 and 0.21, respectively. Conclusion: The establishment of the new standardized growth reference values and growth curves of length for weight and head circumference for weight among Chinese newborns are useful for clinical practice and scientific research.

[Clinical characteristics of patients with obstructive sleep apnea hypopnea syndrome combined with alveolar hypoventilation]

Objective: To evaluate the clinical characteristics of patients with obstructive sleep apnea hypopnea syndrome (OSAHS) combined with alveolar hypoventilation. Methods: This retrospective study included patients who were diagnosed as OSAHS by polysomnography (PSG) and underwent daytime awake transcutaneous carbon dioxide (PtcCO₂) monitoring from November 2019 to February 2021 at the Sleep Center of the Second Affiliated Hospital of Soochow University. A total of 177 patients were enrolled in the analysis, including 167 males and 10 females, aged (40±8) years old. Patients with daytime awake PtcCO₂>45 mmHg (1 mmHg=0.133 kPa) were diagnosed as daytime alveolar hypoventilation, with which participants were divided into the daytime alveolar hypoventilation group and non-daytime alveolar hypoventilation group. Body mass index (BMI) cut-off value predicting daytime alveolar hypoventilation was calculated and the patients were divided into the high BMI group and low BMI group. The continuous nocturnal PtcCO₂ data was available for a subset of 128 patients, and the patients were divided into two groups according the daytime alveolar hypoventilation or not. Across-group differences were compared, respectively. Results: Compared with the non-daytime alveolar hypoventilation group (n=125), the BMI [27.57 (26.55, 30.33) vs 26.60 (25.06, 28.09) kg/m²], Epworth sleepiness score(ESS) score [9.50 (6.25, 12.00) vs 7.00 (4.00, 10.75)], higher oxygen desaturation index (ODI) [38.00 (15.23, 64.93) vs 26.80 (11.30, 44.30) events/h] and percentage of total time with oxygen saturation level<90% (TS90%) [11.24% (1.88%, 32.44%) vs 4.35% (0.72%, 9.87%)] of the daytime alveolar hypoventilation group(n=52) were significantly higher (P<0.05), and lowest arterial oxygen saturation (LSaO₂) [74.50% (60.25%, 82.00%) vs 79.00% (73.00%, 84.50%)], mean arterial oxygen saturation (MSaO₂) [94.00% (91.00%, 95.00%) vs 95.00% (94.00%, 96.00%)] were significantly lower (P<0.05). The BMI cut-off value for predicting daytime alveolar hypoventilation was 27.04 kg/m². Of the 177 enrolled patients, 90 were in the high BMI group and 87 were in low group. Compared with the low BMI group, the proportion of daytime sleepiness, the ESS score, the prevalence of hypertension, AHI and daytime awake PtcCO₂ in the high BMI group were significantly higher (P<0.05). Among the subset of 128 patients with nocturnal PtcCO₂ data available, the BMI, daytime PtcCO₂ level, the nocturnal CO₂ level and the prevalence of sleep related alveolar hypoventilation in the daytime alveolar hypoventilation group (n=40) were significantly higher than those in the non-daytime alveolar hypoventilation group (n=88) (P<0.05). Conclusions: The OSAHS patients with alveolar hypoventilation have higher BMI and more severe nocturnal hypoxia. OSAHS patients with BMI>27.04 kg/m² are more likely to develop sleep related alveolar hypoventilation disorder.

[Focus on the importance of classification of hyperglycemia in pregnancy and diagnostic criteria for gestational diabetes mellitus]

Hyperglycemia in pregnancy (HIP) is the most common pathological obstetric disease. However, there is no uniform standard in the world for classification of HIP and diagnosis of gestational diabetes mellitus(GDM). This article will analyze this issue and support the International association of diabetes and pregnancy study group(IADPSG) criteria as a global standard for diagnosing GDM,also support HIP should be divided into four categories: PGDM, ODM, GDM and prediabetes, so as to refine clinical management.

MET Receptor Tyrosine Kinase Regulates Lifespan Ultrasonic Vocalization and Vagal Motor Neuron Development

The intrinsic muscles of the larynx are innervated by the vagal motor nucleus ambiguus (nAmb), which provides direct motor control over vocal production in humans and rodents. Here, we demonstrate in mice using the Phox2b Cre line, that conditional embryonic deletion of the gene encoding the MET receptor tyrosine kinase (MET) in the developing brainstem (cKO) results in highly penetrant, severe deficits in ultrasonic vocalization in early postnatal life. Major deficits and abnormal vocalization patterns persist into adulthood in more than 70% of mice, with the remaining recovering the ability to vocalize, reflecting heterogeneity in circuit restitution. We show that underlying the functional deficits, conditional deletion of Met results in a loss of approximately one-third of MET+ nAmb motor neurons, which begins as early as embryonic day 14.5. The loss of motor neurons is specific to the nAmb, as other brainstem motor and sensory nuclei are unaffected. In the recurrent laryngeal nerve, through which nAmb motor neurons project to innervate the larynx, there is a one-third loss of axons in cKO mice. Together, the data reveal a novel, heterogenous MET-dependence, for which MET differentially affects survival of a subset of nAmb motor neurons necessary for lifespan ultrasonic vocal capacity.

[Effects of daytime hypercapnia on logical memory and working memory in patients with obstructive sleep apnea hypopnea syndrome]

Objective: To investigate the effects of daytime hypercapnia on logical memory and working memory in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). Methods: This prospective study recruited patients complaining of snoring and diagnosed with OSAHS at the Sleep Center of the Second Affiliated Hospital of Soochow University from January to November 2020. Patients were assessed clinically and scored for their memory function. All patients underwent daytime transcutaneous carbon dioxide (PtcCO₂) test, and overnight polysomnography (PSG). Logical memory was scored using the Logical Memory Test (LMT), while working memory was evaluated by Digit Span Test (DST) and Cambridge Neuropsychological Test Automated Battery (CANTAB) which included Pattern Recognition Memory (PRM), Spatial Span (SSP), and Spatial Working Memory (SWM). Patients were divided into the normocapnic group and the hypercapnic group using the daytime PtcCO₂ test. The clinical and PSG parameters and the memory test scores between the two groups were compared. Binary logistic stepwise regression was conducted to identify risk factors of memory impairment in OSAHS patients. Results: Among the 123 enrolled OSAHS patients, 79 were normocapnic and 44 were hypercapnic. There was no significant difference in the general clinical parameters between the two groups. The snoring history in years in the hypercapnic group was longer than that in the normocapnic group (P<0.05). Compared with the normocapnic group, the apnea-hyponea index (AHI), oxygen desaturation index (ODI) and percentage of total sleep time with oxygen saturation level<90% (TS90) of the hypercapnic group were higher (all P<0.05), while other PSG parameters exhibited no statistically significant differences. There was no statistically significant difference in the immediate logical memory and PRM immediate accuracy rate between the two groups, while the delayed logical memory, verbal and spatial working memory, and executive function were worse in the hypercapnic group, as shown by lower total LMT scores, lower DST, lower SSP scores (all P<0.05), and higher between errors and strategy scores (P<0.01) of SWM in the hypercapnic group. Binary logistic stepwise regression showed that PtcCO₂ ≥45 mmHg (1 mmHg=0.133 kPa, OR=3.055, 95%CI 1.359-6.868, P=0.007) and higher body mass index (BMI) (OR=1.132, 95%CI 1.005-1.275, P=0.041) were risk factors for poor performance in Digit Span Backwards Test. Therefore, PtcCO₂ ≥45 mmHg was an independent risk factors for poor performance in delayed LMT, SSP, and between errors and strategy scores in SWM (OR=3.109, 3.941, 3.238 and 2.785, respectively, all P<0.05). Conclusion: Hypercapnia had negative impacts on logical memory and working memory of OSAHS patients, especially on the delayed logical memory, verbal working memory and spatial working memory impairment.

[Relationship between emotional apathy and motor symptoms, sleep and cognitive function in patients with early Parkinson's disease]

Objective: To study the relationship between emotional apathy and motor symptoms, sleep, and cognitive function in patients with early Parkinson's disease (PD). Methods: One hundred and twenty-nine early PD patients who were treated in the Second Affiliated Hospital of Soochow University from June to October 2020 were included, including 82 male and 47 female patients. The emotional apathy was assessed by modified apathy rating scale (MAES). The above 129 patients were divided into 67 patients in the PD with emotional apathy group (MAES>14 points) and 62 patients in the PD without emotional apathy group (MAES≤ 14 points). Age, gender, course of disease and levodopa equivalent dose were also collected. Hoehn-Yahr stage and unified Parkinson's disease rating scale PartⅢ(UPDRS-Ⅲ), Pittsburgh Sleep Quality Index (PSQI), polysomnography, and Montreal Cognitive Assessment Scale (MoCA) were used to evaluate the motor symptoms, sleep and cognitive functions of patients with early PD, and the clinical characteristics of patients with early PD with apathywere determined. Results: Compared with PD patients without apathy, those with apathy had longer disease duration [M(Q₁,Q₃)][5.0 (3.0, 7.0) years vs 3.0 (2.0, 5.0) years, P=0.006] and severer motor symptoms [20.0 (10.0, 28.0) vs 14.0 (8.5, 23.0), P=0.047]. There was no significant difference in PSQI score between the two groups. Among the 33 patients who completed polysomnography, compared with PD patients without apathy (n=16), those with apathy (n=17) had a longer rapid eye movement (REM) sleep latency [150 (124, 184) min vs 87 (57, 133) min, P=0.035)] and more frequent periodic limb movements in the REM phase(P=0.042).The REM sleep ratio (r=0.373, P=0.042), apnea-hypopena index (AHI)(r=0.374, P=0.046) and oxygen deficit index (r=0.409, P=0.025) were positively correlated with the degree of apathy in PD patients. PD patients with apathy had relatively poorer performance in cognition assessment than those without apathy and total MoCA score was inversely correlated with the degree of apathy (r=-0.231, P=0.017). Conclusion: Early PD patients with apathy have objective sleep disorders dominated by REM sleep disorders, which can have a negative impact on cognitive function.

[Reference values and growth curves of weight/length, body mass index, and ponderal index of Chinese newborns of different gestational ages]

Objective: To establish the reference values and growth curves of weight/length, body mass index, and ponderal index for Chinese newborns with gestational ages of 24 to 42 weeks, in order to provide a reference for the assessment of body proportionality and nutritional status at birth. Methods: Cross-sectional study design was applied. From June 2015 to November 2018, a total of 24 375 singleton live birth newborns with gestational ages of 24 to 42 weeks from 13 cities including Beijing, Harbin, Xi'an, Shanghai, Nanjing, Wuhan, Guangzhou, Fuzhou, Kunming, Tianjin, Shenyang, Changsha, and Shenzhen were selected, excluding those impacting the establishment of the reference values. The generalized additive model for location, scale, and shape (GAMLSS) was employed to establish percentile (P₃, P₁₀, P₂₅, P₅₀, P₇₅, P₉₀, P₉₇) reference values and growth curves of weight/length, body mass index, and ponderal index for male and female newborns with gestational ages of 24 to 42 weeks. The established growth standards in this study were compared with the standards from the 1988 Chinese data, the INTERGROWTH project, and the USA reference values. Results: A total of 24 375 newborns with 12 264 preterm newborns (7 042 males and 5 222 females) and 12 111 full-term newborns (6 155 males and 5 956 females) were included in this study. The percentile reference values and growth curves of weight/length, body mass index, and ponderal index were obtained for male and female newborns with gestational ages of 24 to 42 weeks. Weight/length of males in all gestational ages at P₁₀, P₅₀ and P₉₀ was 0 to 0.2 kg/m higher than that of females, and body mass index of males in all gestational ages at the P₁₀, P₅₀ and P₉₀ was 0.1 to 0.3 kg/m² higher than that of females. The established growth curves of weight/length and body mass index at the upper percentile and ponderal index at both upper and lower percentiles were greatly different from those of the 1988 Chinese data, which, for example, reported the difference ranges at P₉₀ as -1.09 to 0.40 kg/m for weight/length, -1.19 to 0.92 kg/m² for body mass index, and -0.64 to 0.81 kg/m³ for ponderal index. The established weight/length curves were generally consistent with the reference values from the INTERGROWTH project with a difference of -0.17 to 0.20 kg/m at P₅₀, while being 0.02 to 0.40 kg/m lower at P₉₀ and 0.13 to 0.41 kg/m higher at P₁₀ than that of the INTERGROWTH reference values at gestational ages of ≤32 weeks. The established body mass index curves differed from that of the USA reference values with a difference of -0.47 to 0.17 kg/m² at P₅₀, while being 0.53 to 1.10 kg/m² lower at gestational ages of ≥37 weeks but 0.17 to 0.45 kg/m² higher at gestational ages of ≤28 weeks than that of the USA reference values at P₉₀. Conclusion: The establishment of the new standardized growth reference values of weight/length, body mass index, and ponderal index for Chinese newborns by different gestational ages are useful for clinical practice and scientific research.

Developmental Connectivity and Molecular Phenotypes of Unique Cortical Projection Neurons that Express a Synapse-Associated Receptor Tyrosine Kinase

The complex circuitry and cell-type diversity of the cerebral cortex are required for its high-level functions. The mechanisms underlying the diversification of cortical neurons during prenatal development have received substantial attention, but understanding of neuronal heterogeneity is more limited during later periods of cortical circuit maturation. To address this knowledge gap, connectivity analysis and molecular phenotyping of cortical neuron subtypes that express the developing synapse-enriched MET receptor tyrosine kinase were performed. Experiments used a MetGFP transgenic mouse line, combined with coexpression analysis of class-specific molecular markers and retrograde connectivity mapping. The results reveal that MET is expressed by a minor subset of subcerebral and a larger number of intratelencephalic projection neurons. Remarkably, MET is excluded from most layer 6 corticothalamic neurons. These findings are particularly relevant for understanding the maturation of discrete cortical circuits, given converging evidence that MET influences dendritic elaboration and glutamatergic synapse maturation. The data suggest that classically defined cortical projection classes can be further subdivided based on molecular characteristics that likely influence synaptic maturation and circuit wiring. Additionally, given that MET is classified as a high confidence autism risk gene, the data suggest that projection neuron subpopulations may be differentially vulnerable to disorder-associated genetic variation.

[Timing of permanent tooth emergence and its association with physical growth among children aged from four to seven years in nine cities of China]

Objective: To investigate the timing of permanent tooth emergence and its association with physical growth among children aged 4-7 years in 9 cities of China, and to analyze the trend of permanent teeth development. Methods: According to a stratified cluster sampling design, a cross-sectional survey on the timing of permanent tooth emergence children aged 4-7 years was carried out in 9 cities (Beijing, Harbin and Xi'an in northern China; Shanghai, Nanjing and Wuhan in central China; Guangzhou, Fuzhou and Kunming in southern China) from June to October in 2015. A total of 37 973 children (19 035 boys and 18 938 girls) were recruited and were divided into different age groups (4.0-<4.5, 4.5-5.0, 5.0-5.5 and 6.0-<7.0 years of age). The situation of the exfoliation of primary teeth and the eruption of permanent teeth were investigated. Height and weight were measured using the standardized methods. Z-scores of physical growth indicators were calculated using the growth standards for Chinese children in 2009. Probit regression analysis was used to determine the median and percentile age of transition from deciduous to permanent teeth. Chi-square test was used for comparison of categorical data and t test was used for comparison of measurement data between boys and girls, urban and suburban as well as among different ages and regions. Meanwhile, the data from the national survey on physical growth and development of children under 7 years of age in 9 cities of China in 1995 were used to analyze the trends of the permanent teeth development. Results: The rate of transition from deciduous to permanent teeth in 37 973 children aged 4-7 years was higher with age, which was 0.6% (42/7 568) in 4.0-<4.5 years of age group, 30.3% (2 295/7 583) in 5.5-<6.0 years of age group, and 74.5% (5 680/7 627) in 6.0-<7.0 years of age group. The rates of transition from deciduous to permanent teeth in boys were all lower than those of girls except for children aged 4.0-<4.5 years (all P<0.01). The rate of transition from deciduous to permanent teeth in urban children was higher than that in suburban children for older than 5.5-6.0 years of age group in boys and older than 4.5-5.0 years of age group in girls, which was 74.2% (1 427/1 924) in urban boys aged 6.0-<7.0 years and 69.2% (1 305/1 885) in suburban boys aged 6.0-<7.0 years (χ(2)=11.446, P<0.01). The age of transition from deciduous to permanent teeth was 6.00 (95%CI: 5.98-6.01) years and the range of the 3-97 percentile was 4.88-7.11 years of age. The median permanent tooth emergence age of girls was lower than that of boys (5.94 vs. 6.06 years) and the median age of urban children was lower than that of suburban children (5.94 vs. 6.05 years). The median permanent tooth emergence age of southern Chinese children (6.05 years) was higher than that of northern (5.97 years) and central Chinese children (5.97 years). The weight for age Z-scores (WAZ), height for age Z-scores (HAZ) and body mass index for age Z-scores (BMIZ) of children with transition from deciduous to permanent teeth (0.35±1.17, 0.32±1.00, 0.23±1.16) were significantly higher than those of children without transition from deciduous to permanent teeth (0.03±1.13, 0.03±1.02, 0.04±1.13, t=20.81,21.67,12.09, all P<0.05). In comparison with the data in 1995, data in 2015 showed that the rate of transition from deciduous to permanent teeth was higher, for example, the rate of urban boys aged 6.0-<7.0 years group was 63.8% (1 146/1 796) in 1995, and increased to 74.2% (1 427/1 924) in 2015 (χ(2)=46.748, P<0.01). The median permanent tooth emergence age decreased by 0.24 years in 2015 as compared with that in 1995. Conclusions: The development of permanent teeth is earlier in girls than in boys, earlier in urban children than in suburban children and slightly delay in southern children than in central and northern Chinese children. In addition, the development of permanent teeth, which is related to the physical growth, slightly accelerate in China during the past 20 years.

[Survey on the stunting of children under seven years of age in nine cities of China]

Objective: To survey the children under 7 years of age in nine cities of China for a better understanding of the current situation of childhood stunting. Methods: According to a stratified cluster sampling design, a cross-sectional survey on children under 7 years of age was carried out in 9 cities (Beijing, Harbin and Xi'an in northern China; Shanghai, Nanjing and Wuhan in central China; and Guangzhou, Fuzhou and Kunming in southern China) from June to November in 2016. A total of 110 499 children were recruited. Height of children was evaluated using the growth standards for Chinese children (2009 edition) .Children with height less than the 3rd percentile of the growth standards were considered as stunting, and children with height between the 3rd and 10th percentiles of the growth standards were considered as relatively short stature. Chi-square test was used for comparison between data of boys and girls, urban and suburban, as well as among different ages and regions. Results: Totally 113 084 children under 7 years of age should be investigated and actually 110 499 children were investigated, with a rate of 97.7%. The prevalence of stunting was 1.9% (2 141/110 499) among all the children. The prevalence of stunting in urban children (1.6%, 904/55 524) was lower than that in suburban children (2.3%, 1 237/54 975, χ(2)=56.246, P<0.01). The gender difference in stunting prevalence was not statistically significant (1.9% (1 121/57 921) in boys and 1.9% (1 020/52 578) in girls, χ(2)=0.003, P=0.965). The prevalence of stunting decreased with age for children younger than 3 years, from 1.8% (312/17 080) in 0-<1 year of age group to 1.2% (168/13 740) in 2-<3 years of age group, but increased to 2.2% (240/11 073) at 6-<7 years group. Comparison among different regions showed that the stunting prevalence in southern region was higher than those in the central and northern regions (0.9% (193/20 374) in northern urban, 0.8% (154/18 486) in central urban, and 3.3% (557/16 664) in southern urban children), showing a statistical significance (χ(2)=437.736, P<0.01); 1.1% (241/21 924) in northern suburban, 1.4% (227/16 775) in central suburban and 4.7% (769/16 276) in southern suburban children, showing a statistical significance (χ(2)=646.533, P<0.01). In urban areas, the difference between the central and northern regions showed no statistical significance (χ(2)=1.429, P=0.232) and the stunting prevalence of central Chinese children was slightly higher than that of northern Chinese children in suburban areas (χ(2)=5.130, P=0.024). Among the nine cities, the stunting prevalence of Guangzhou (6.1%, 613/10 019) was higher than those of other cities (χ(2)=1 559.64, P<0.01). Among the stunting children, 78.4% (1 679/2 141) were classified as borderline or mild and only 7.2% (154/2 141) were classified as severe. The prevalence of relatively short stature was 5.2% (5 721/110 499). Conclusions: The prevalence of stunting among children under 7 years of age in nine cities of China is low and most of the stunting children were classified as mild; the prevalence of stunting in suburban children is higher than that in urban children; the gender difference show no statistical significance; and the prevalence of stunting in southern Chinese children is higher than those in central and northern Chinese children.

[Progress of interruption of schistosomiasis transmission in Jiangsu Province]

Schistosomiasis was once heavily endemic in Jiangsu Province. Following the control efforts for several decades, schistosomiasis was almost eradicated in all endemic counties in Jiangsu Province in 1980, and transmission control was achieved in the province in 2011. According to the principle of "implementing the control measures with adaptation to local circumstances and guiding the control programs with classified interventions", an integrated strategy with emphasis on the management of both infectious sources and snails has been recently employed for schitsosomiasis control in Jiangsu Province. In addition, a sensitive and highly effective surveillance system has been built and the application of novel techniques and information construction has been intensified to effectively interrupt the transmission of schistosomiasis in the Province. Transmission interruption of schistosomiasis was achieved in all endemic counties in Jiangsu Province. The paper summarizes the endemic situation of schistosomiasis, progress of schistosomiasis control, and major schistosomiasis control measures implemented during the stage of transmission interruption in Jiangsu Province.

A magneto-microfluidic platform for fluorescence immunosensing using quantum dot nanoparticles

This study reports the online fluorescent detection of carcinoembryonic antigen (CEA) and α-fetoprotein (AFP) biomarker proteins in microfluidic channels using functional nanoparticles. Functional magnetic nanoparticles labeled with two antibodies were predeposited on separated microfluidic channels. Antigens were passed through each microfluidic channel to react with the respective antibodies. Two types of fluorescent nanoparticles labeled with antibodies were then used to detect and confirm antigens in the immunocomplex. Results indicate that online fluorescent detection of proteins can provide advantages for real-time monitoring and diagnostic applications. The running time was less than 20 min for each trial. The detection limits of CEA and AFP were found to be 0.6 and 0.2 pg ml^-1. These detection limits are lower than those of ELISA. The linear ranges of CEA and AFP detection were from 1.8 pg ml^-1 to 1.8 ng ml^-1 and from 0.68 pg ml^-1 to 0.68 ng ml^-1 for two deposition zones in a magnetic sandwich immunoassay. The linear ranges of this method are wider than those of ELISA and those of most other methods. The measurements of CEA and AFP in serum samples from this method differed from ELISA results by 11% and 9.4%, respectively. The detection limit of online detection has achieved the same range as those of previous offline detection. This method has a good potential for automation and multichannel analysis to increase the throughput with some modifications in the future. The proposed method can provide simple, fast, and sensitive online detection for biomarkers.

[Development of primary teeth among infants and toddlers in nine cities of China in 2015]

Objective: To investigate the status of the development of primary teeth and to identify the development patterns among infants and toddlers in nine cities of China in 2015. Methods: Healthy children aged 1-<36 months were investigated by across-sectional survey and retrospective studies, which was carried out in 9 cities (Beijing, Harbin and Xi'an in northern China; Shanghai, Nanjing and Wuhan in central China; and Guangzhou, Fuzhou and Kunming in southern China) from June to October in 2015. Subjects (n=103 995) were divided into 14 age groups (1-<2, 2-<3, 3-<4, 4-<5, 5-<6, 6-<8, 8-<10, 10-<12, 12-<15, 15-<18, 18-<21, 21-<24, 24-<30, 30-<36 months). There were 150-200 boys and girls respectively in each group of urban and suburb areas in each city. The eruption status and the number of primary teeth were examined by the trained child health care physician or pediatrician on the spot. The timing of primary teeth eruption of children was retrospectively surveyed using a questionnaire. The prevalence of primary teeth was calculated and χ(2) test was used for comparison of categorical data. Probit regression analysis was used to determine the median and percentile age of eruption of primary teeth. Results: Totally 103 995 children aged 1-<36 months were investigated. There were 52 346 children in urban areas (boys 26 228, girls 26 118) and 51 649 children in suburb areas (boys 25 912, girls 25 737). The eruption rate of primary teeth in children under 2 years became higher with age and the difference among each age group was statistically significant (χ(2)=85 913.868, P<0.01), which was 0.3% (22/7 450) in 3-<4 months group, 43.0% (3 227/7 503) in 6-<8 months group and 99.9% (7 441/7 446) in 15-<18 months group. The eruption age of primary teeth was 6.6 months (95%CI: 6.5-6.7 months), and the range of the 3rd to 97th percentile was 4.1-10.6 months. The eruption ages of primary teeth in urban and suburb areas children were 6.6 months (95%CI: 6.5-6.7 months) and 6.6 months (95%CI: 6.5-6.7 months) respectively. The eruption age of primary teeth was earlier in boys (6.4 months, 95%CI: 6.3-6.5 months) than that in girls (6.7 months, 95%CI: 6.6-6.8 months). The median eruption age of primary teeth was earlier in northern China (6.2 months) than that in central (6.7 months) and southern China (6.9 months). The eruption rate of primary teeth became higher with age, showing that the median number of primary teeth was 2 in 8-<10 months group, 8 in 12-<15 months group and 20 in 30-<36 months group. Conclusions: The timing of eruption of primary teeth was similar between urban and suburb areas children and that of the boys was slightly earlier than that of the girls. There were slight differences among different regions in the eruption timing of primary teeth. The range of the 3rd to 97th percentile in the eruption age of primary teeth was 4.1-10.6 months and the number of primary teeth followed the regular development pattern with age.

OR12-1 Leptin Is Transported across the Mouse Placenta

The placenta is critical for mother-fetus physiological communication. It is particularly sensitive to changes in the nutritional and hormonal environments and can contribute to the programming of metabolic syndrome. Recent data, including from our laboratory, showed that the hormone leptin influences brain development during fetal life and mediates lifelong metabolic regulations. However, despite the documented capacity of the placenta in transporting various maternally-derived molecules, it is still unclear whether the placenta contributes to circulating fetal leptin. Here, we report that high levels of leptin receptor mRNA were detected in the mouse placenta during mid-gestation, particularly in trophoblast giant cells of the labyrinth zone, where mother-fetus exchanges take place. Remarkably, the main leptin receptor isoform expressed in the placenta was LepRa, which is critical for transporting leptin across cellular barriers. In addition, we found that leptin-deficient (ob/ob) embryos raised by heterozygous dams have significant levels of circulating leptin. Since the mouse placenta does not express leptin mRNA, this data support the idea that fetal leptin is maternally-derived. To further examine leptin transport from mother to fetus, fluorescently labeled bioactive leptin was injected through the tail vein of wild-type dams. Fluorescence was detected not only in the placenta but also in embryo including the hypothalamus, liver and pancreas as early as one minute after injection. In addition, maternally-injected leptin induces STAT3 activation in the placenta and various organs, including the CNS, of the embryo. We are currently examining whether this trans-placental leptin transport is altered in a context of maternal obesity. Taken together, our data provide direct evidence that maternal leptin is transported to the fetus across the mouse placenta.

Performance of Arma chinensis reared on an artificial diet formulated using transcriptomic methods

An artificial diet formulated for continuous rearing of the predator Arma chinensis was inferior to natural prey when evaluated using life history parameters. A transcriptome analysis identified differentially expressed genes in diet-fed and prey-fed A. chinensis that were suggestive of molecular mechanisms underlying the nutritive impact of the artificial diet. Changes in the diet formulation were made based on the transcriptome analysis and tested using life history parameters. The quantity of pig liver, chicken egg, tuna fish, biotin, nicotinamide, vitamin B6, thiamine, riboflavin, vitamin C, L-glutamine, and sucrose was reduced, and wheat germ oil, calcium pantothenate and folic acid were increased. Ecuadorian shrimp was added as a partial substitute for tuna fish. Several parameters improved over six generations, including increased egg viability, and decreased egg and adult cannibalism. Additionally, several parameters declined, including longer developmental times for 2nd-5th instars, and decreased nymphal weights. The improvements in life history parameters support the use of transcriptome analyses to help direct formulation improvements. However, the decline in some parameters suggests that additional information, e.g., proteomic data, may be useful as well to maximize diet formulations.

Preventing arteriovenous shunt failure in hemodialysis patients: a population-based cohort study

Essentials Uncertainty remains about antiplatelets for vascular access patency in hemodialysis patients. 95 971 people under hemodialysis were followed in a claims database in Taiwan. Aspirin reduced vascular access failure rate and did not increase major bleeding rate. Clopidogrel, Aggrenox, and warfarin might increase major bleeding rate. SUMMARY: Background Dialysis adequacy is a major determinant of survival for patients with end-stage renal disease. Good vascular access is essential to achieve adequate dialysis. Objectives This study evaluated the impacts of different drugs on the vascular access failure rate of an arteriovenous fistula or an arteriovenous graft and the rate of major bleeding in hemodialysis patients. Patients and methods We studied patients with end-stage renal disease registered in the Taiwan National Health Insurance program from 1 January 1997 to 31 December 2012. A total of 95 971 patients were enrolled in our study. Vascular access dysfunction was defined as the need for thrombectomy or percutaneous angioplasty. Major bleeding was defined as emergency department visits or hospitalization with a primary diagnosis of gastrointestinal bleeding or intracerebral hemorrhage. The adjusted odds ratios between person-quarters with or without antiplatelet or oral anticoagulant use were calculated using a generalized estimating equation. Results The odds ratio of vascular access failure was 0.21 (0.11-0.39) for aspirin, 0.76 (0.74-0.79) for clopidogrel, 0.67 (0.59-0.77) for dipyridamole, 0.67 (0.53-0.86) for Aggrenox and 0.96 (0.90-1.03) for warfarin. The highest odds ratio for intracerebral hemorrhage was 5.33 (1.25-22.72) in younger patients using Aggrenox. The highest odds ratio for gastrointestinal bleeding was 1.34 (1.10-1.64) for clopidogrel. Conclusion Antiplatelet agents, but not warfarin, might reduce the vascular access thrombosis rate. The gastrointestinal bleeding rate was increased in the group using clopidogrel. Aggrenox should be used with caution in young individuals because it might increase the rate of intracerebral hemorrhage.

An unsuspected role for organic cation transporter 3 in the actions of amphetamine

Amphetamine abuse is a major public health concern for which there is currently no effective treatment. To develop effective treatments, the mechanisms by which amphetamine produces its abuse-related effects need to be fully understood. It is well known that amphetamine exerts its actions by targeting high-affinity transporters for monoamines, in particular the cocaine-sensitive dopamine transporter. Organic cation transporter 3 (OCT3) has recently been found to play an important role in regulating monoamine signaling. However, whether OCT3 contributes to the actions of amphetamine is unclear. We found that OCT3 is expressed in dopamine neurons. Then, applying a combination of in vivo, ex vivo, and in vitro approaches, we revealed that a substantial component of amphetamine's actions is OCT3-dependent and cocaine insensitive. Our findings support OCT3 as a new player in the actions of amphetamine and encourage investigation of this transporter as a potential new target for the treatment of psychostimulant abuse.

[Clinical characteristics of silent pheochromocytoma]

Objective: To summarize the clinical characteristics of silent paraganglioma. Methods: A total of 247 pheochromocytoma cases in Peking University First Hospital between January 1993 and December 2015 were analyzed retrospectively.The cases were divided into two groups according to whether they had hypertension: non-silent group (193 cases) and silent group (53 cases), then the clinical characteristics between the groups were compared, and the clinical features of silent pheochromocytoma were reviewed. Results: There were 53 silent pheochromocytoma cases in this study, which accounted for 21.5% (53/247), and imaging was the main way to find the tumor. Forty-one in 53 cases (77.4%) located in adrenal gland, in which 31 cases (75.6%) were benign and 2.3-8.0 cm in diameter, while 10 cases (24.4%) were malignant and 3.5-12.0 cm in diameter. Twelve in 53 cases (22.6%) located in extra-adrenal tissue, in which 4 cases were benign and 2.0-5.5 cm in diameter, while 8 cases were malignant and 5.0-10.5 cm in diameter. With the tumor diameter increased, the malignant rate increased: 1 in 8 cases in diameter<3 cm, 2 in 12 cases in diameter 3-5 cm, 15 in 33 cases in diameter>5 cm were malignant. There was no significant difference in age, sex, tumor location, benign or malignant rate between the two groups (all P>0.05). Compared with the non-silent group, the proportion of tumor size≥5 cm in silent group was significantly higher (62.3% vs 45.9%, P=0.034), and the incidence of hyperglycemia and the concentrations of norepinephrine and epinephrine were lower (all P<0.05) in silent group.Misdiagnosis was common in silent group, and up to 35.8% (19/53) had not been diagnosed correctly before operation. Twenty-one in 53 (39.6%) silent pheochromocytoma cases occured severe intra-operative blood pressure fluctuation. Conclusions: Silent pheochromocytoma was not uncommon and imaging was the main way to find it. The tumor size was always big and misdiagnosis was common, especially extra-adrenal tumors. Therefore, regardless of the adrenal or extra-adrenal tumors, especially in diameter>3.0 cm but with normal blood pressure, the possibility of silent pheochromocytoma should be considered. In order to reduce misdiagnosis and intra-operative blood pressure fluctuations, preoperative diagnosis and preparation, as well as intra-operative monitoring should be fully made.

Polarization rotation and the electrocaloric effect in barium titanate

We study the electrocaloric effect in the classic ferroelectric BaTiO₃ through a series of phase transitions driven by applied electric field and temperature. We find both negative and positive electrocaloric effects, with the negative electrocaloric effect, where temperature decreases with applied field, in monoclinic phases. Macroscopic polarization rotation is evident through the monoclinic and orthorhombic phases under applied field, and is responsible for the negative electrocaloric effect.

Distinct projection targets define subpopulations of mouse brainstem vagal neurons that express the autism-associated MET receptor tyrosine kinase

Detailed anatomical tracing and mapping of the viscerotopic organization of the vagal motor nuclei has provided insight into autonomic function in health and disease. To further define specific cellular identities, we paired information based on visceral connectivity with a cell-type specific marker of a subpopulation of neurons in the dorsal motor nucleus of the vagus (DMV) and nucleus ambiguus (nAmb) that express the autism-associated MET receptor tyrosine kinase. As gastrointestinal disturbances are common in children with autism spectrum disorder (ASD), we sought to define the relationship between MET-expressing (MET+) neurons in the DMV and nAmb, and the gastrointestinal tract. Using wholemount tissue staining and clearing, or retrograde tracing in a MET^EGFP transgenic mouse, we identify three novel subpopulations of EGFP+ vagal brainstem neurons: (a) EGFP+ neurons in the nAmb projecting to the esophagus or laryngeal muscles, (b) EGFP+ neurons in the medial DMV projecting to the stomach, and (b) EGFP+ neurons in the lateral DMV projecting to the cecum and/or proximal colon. Expression of the MET ligand, hepatocyte growth factor (HGF), by tissues innervated by vagal motor neurons during fetal development reveal potential sites of HGF-MET interaction. Furthermore, similar cellular expression patterns of MET in the brainstem of both the mouse and nonhuman primate suggests that MET expression at these sites is evolutionarily conserved. Together, the data suggest that MET+ neurons in the brainstem vagal motor nuclei are anatomically positioned to regulate distinct portions of the gastrointestinal tract, with implications for the pathophysiology of gastrointestinal comorbidities of ASD.

Specific Connectivity and Unique Molecular Identity of MET Receptor Tyrosine Kinase Expressing Serotonergic Neurons in the Caudal Dorsal Raphe Nuclei

Molecular characterization of neurons across brain regions has revealed new taxonomies for understanding functional diversity even among classically defined neuronal populations. Neuronal diversity has become evident within the brain serotonin (5-HT) system, which is far more complex than previously appreciated. However, until now it has been difficult to define subpopulations of 5-HT neurons based on molecular phenotypes. We demonstrate that the MET receptor tyrosine kinase (MET) is specifically expressed in a subset of 5-HT neurons within the caudal part of the dorsal raphe nuclei (DRC) that is encompassed by the classic B6 serotonin cell group. Mapping from embryonic day 16 through adulthood reveals that MET is expressed almost exclusively in the DRC as a condensed, paired nucleus, with an additional sparse set of MET+ neurons scattered within the median raphe. Retrograde tracing experiments reveal that MET-expressing 5-HT neurons provide substantial serotonergic input to the ventricular/subventricular region that contains forebrain stem cells, but do not innervate the dorsal hippocampus or entorhinal cortex. Conditional anterograde tracing experiments show that 5-HT neurons in the DRC/B6 target additional forebrain structures such as the medial and lateral septum and the ventral hippocampus. Molecular neuroanatomical analysis identifies 14 genes that are enriched in DRC neurons, including 4 neurotransmitter/neuropeptide receptors and 2 potassium channels. These analyses will lead to future studies determining the specific roles that 5-HT^MET+ neurons contribute to the broader set of functions regulated by the serotonergic system.

Differential patterning of genes involved in serotonin metabolism and transport in extra-embryonic tissues of the mouse

INTRODUCTION

Serotonin (5-HT) is an important neuromodulator, but recently has been shown to be involved in neurodevelopment. Although previous studies have demonstrated that the placenta is a major source of forebrain 5-HT during early forebrain development, the processes of how 5-HT production, metabolism, and transport from placenta to fetus are regulated are unknown. As an initial step in determining the mechanisms involved, we investigated the expression patterns of genes critical for 5-HT system function in mouse extraembryonic tissues.

METHODS

Mid-through late gestation expression of 5-HT system-related enzymes, Tph1, Ddc, Maoa, and 5-HT transporters, Sert/Slc6a4, Oct3/Slc22a3, Vmat2/Slc18a2, and 5-HT in placenta and yolk sac were examined, with cell type-specific resolution, using multiplex fluorescent in situ hybridization to co-localize transcripts and immunocytochemistry to co-localize the corresponding proteins and neurotransmitter.

RESULTS

Tph1 and Ddc are found in the syncytiotrophoblast I (SynT-I) and sinusoidal trophoblast giant cells (S-TGC), whereas Maoa is expressed in SynT-I, syncytiotrophoblast II (SynT-II) and S-TGC. Oct3 expression is observed in the SynT-II only, while Vmat2 is mainly expressed in S-TGC. Surprisingly, there were comparatively high expression of Tph1, Ddc, and Maoa in the yolk sac visceral endoderm.

DISCUSSION

In addition to trophoblast cells, visceral endoderm cells in the yolk sac may contribute to fetal 5-HT production. The findings raise the possibility of a more complex regulation of 5-HT access to the fetus through the differential roles of trophoblasts that surround maternal and fetal blood space and of yolk sac endoderm prior to normal degeneration.

Distinct intracellular signaling mediates C-MET regulation of dendritic growth and synaptogenesis

Hepatocyte growth factor (HGF) activation of the MET receptor tyrosine kinase influences multiple neurodevelopmental processes. Evidence from human imaging and mouse models shows that, in the forebrain, disruptions in MET signaling alter circuit formation and function. One likely means of modulation is by controlling neuron maturation. Here, we examined the signaling mechanisms through which MET exerts developmental effects in the neocortex. In situ hybridization revealed that hgf is located near MET-expressing neurons, including deep neocortical layers and periventricular zones. Western blot analyses of neocortical crude membranes demonstrated that HGF-induced MET autophosphorylation peaks during synaptogenesis, with a striking reduction in activation between P14 and P17 just before pruning. In vitro analysis of postnatal neocortical neurons assessed the roles of intracellular signaling following MET activation. There is rapid, HGF-induced phosphorylation of MET, ERK1/2, and Akt that is accompanied by two major morphological changes: increases in total dendritic growth and synapse density. Selective inhibition of each signaling pathway altered only one of the two distinct events. MAPK/ERK pathway inhibition significantly reduced the HGF-induced increase in dendritic length, but had no effect on synapse density. In contrast, inhibition of the PI3K/Akt pathway reduced HGF-induced increases in synapse density, with no effect on dendritic length. The data reveal a key role for MET activation during the period of neocortical neuron growth and synaptogenesis, with distinct biological outcomes mediated via discrete MET-linked intracellular signaling pathways in the same neurons. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1160-1181, 2016.

Molecular Characterization of Six Small Heat Shock Proteins and Their Responses Under Cadmium Stress in Oxya chinensis (Orthoptera: Acridoidea)

Small heat shock proteins (sHSPs) have been implicated in many physiological processes and play important roles in the response to various stresses. In this study, the full-length sequences of six sHSPs: OcHSP19.1, 19.8, 20.4, 20.7, 21.1, and 23.8 were obtained from the rice grasshopper Oxya chinensis transcriptome database. The deduced amino acid sequences of the six OcsHSPs contain a typical α-crystallin domain, which consists of approximately 100 amino acid residues and five β-strands. The phylogenetic analysis suggested that OcHSP23.8 was orthologous to the sHSPs of other species and that OcHSP19.1, 20.4, 20.7, and 21.1 were species specific, whereas OcHSP19.8 did not cluster closely to Orthoptera but was placed on the basal end of the cluster. Developmental stage-dependent and tissue-specific expression patterns were evaluated using quantitative real-time polymerase chain reaction. The six genes were expressed in all developmental stages and showed clear tissue specificity. The cadmium acute experiment indicates that Cd(2+) can induce the six genes. However, various response patterns were observed among these genes under Cd(2+) stress conditions. OcHSP19.1, 19.8, 20.4, and 20.7 were highly induced by 2.61 mM Cd(2+) at 24 h. OcHSP23.8 was significantly upregulated by 2.61 mM Cd(2+) at 6 h. For OcHSP21.1, the highest expression levels were found after treatment with 0.87 mM Cd(2+) for 24 h, 1.74 mM Cd(2+) for 36 h, and 2.61 mM Cd(2+) for 12 h. These differential characteristics will facilitate future investigations into the physiological functions of sHSPs.

Physical Interactions and Functional Relationships of Neuroligin 2 and Midbrain Serotonin Transporters

The neurotransmitter serotonin [5-hydroxytryptamine (5-HT)] modulates many key brain functions including those subserving sensation, emotion, reward, and cognition. Efficient clearance of 5-HT after release is achieved by the antidepressant-sensitive 5-HT transporter (SERT, SLC6A4). To identify novel SERT regulators, we pursued a proteomic analysis of mouse midbrain SERT complexes, evaluating findings in the context of prior studies that established a SERT-linked transcriptome. Remarkably, both efforts converged on a relationship of SERT with the synaptic adhesion protein neuroligin 2 (NLGN2), a post-synaptic partner for presynaptic neurexins, and a protein well-known to organize inhibitory GABAergic synapses. Western blots of midbrain reciprocal immunoprecipitations confirmed SERT/NLGN2 associations, and also extended to other NLGN2 associated proteins [e.g., α-neurexin (NRXN), gephyrin]. Midbrain SERT/NLGN2 interactions were found to be Ca(2+)-independent, supporting cis vs. trans-synaptic interactions, and were absent in hippocampal preparations, consistent with interactions arising in somatodendritic compartments. Dual color in situ hybridization confirmed co-expression of Tph2 and Nlgn2 mRNA in the dorsal raphe, with immunocytochemical studies confirming SERT:NLGN2 co-localization in raphe cell bodies but not axons. Consistent with correlative mRNA expression studies, loss of NLGN2 expression in Nlgn2 null mice produced significant reductions in midbrain and hippocampal SERT expression and function. Additionally, dorsal raphe 5-HT neurons from Nlgn2 null mice exhibit reduced excitability, a loss of GABAA receptor-mediated IPSCs, and increased 5-HT1A autoreceptor sensitivity. Finally, Nlgn2 null mice display significant changes in behaviors known to be responsive to SERT and/or 5-HT receptor manipulations. We discuss our findings in relation to the possible coordination of intrinsic and extrinsic regulation afforded by somatodendritic SERT:NLGN2 complexes.

[Management of pelvic injury associated with complete anterior sacroiliac joint dislocation]

OBJECTIVE

To investigate the management of pelvic injury associated with complete anterior sacroiliac joint dislocation.

METHODS

In the study, 6 cases of pelvic injury associated with complete anterior sacroiliac joint dislocation treated in Beijing Jishuitan Hospital from February 2008 to June 2014 were analyzed. We described the history and severity of injury, emergency treatment, and fracture radiology. In all the cases, the surgical treatment and postoperative functional exercise were performed. We followed up all the cases on an average of 1.6 years, assessed the postoperative recovery and summed up the treatment experience.

RESULTS

All the 6 patients with fractures recovered without infection and nerve symptoms after surgery. Their X-rays showed good reduction of sacroiliac joints. All the cases were followed up on an average of 1.6 years. Six months after surgery, the Majeed scores were perfect in 2 cases, good in 2, fair in 1, and poor in 1. The patients with poor scores suffered persistent pain, and decreased physical activity, and when walking long distances, they needed a walking stick. The 2 patients with low scores could not resume the original work.

CONCLUSION

Pelvic injury associated with complete anterior sacroiliac joint dislocation is a special type of the pelvic injury since the managements during the emergency phase are difficult.The surgery should be done as early as possible, and the anterior approach is available for the reduction and fixation.

Performance and Cost Comparisons for Continuous Rearing of Arma chinensis (Hemiptera: Pentatomidae: Asopinae) on a Zoophytogenous Artificial Diet and a Secondary Prey

The impact of a zoophytogenous, insect-free artificial diet and a secondary prey, pupae of Chinese oak silk moth Antheraea pernyi (Guérin-Méneville) (Lepidoptera: Saturniidae), on the developmental rate, life history parameters, and fertility was examined for F6, F9, and F12 consecutive generations for domesticated Arma chinensis (Fallou) (Heteroptera: Pentatomidae). This study showed that when fed an insect-free artificial diet during both the nymphal and adult stages, developmental times were prolonged, and fecundity, egg viability, net reproductive rates (R0), and intrinsic rates of increase (rm) declined. As a result, the cost to rear A. chinensis on the artificial diet approached 1.7 times the cost of rearing A. chinensis on pupae of A. pernyi. Future diet improvements should attempt to reduce developmental time, increase fecundity, and egg viability and use less costly nutrient sources.

EUS-guided FNA cytology of pancreatic neuroendocrine tumour (PanNET): a retrospective study of 132 cases over an 18-year period in a single institution

OBJECTIVE

To determine the diagnostic accuracy and pitfalls of endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) cytology of pancreatic neuroendocrine tumour (PanNET).

METHODS

A search of our laboratory information system was performed from July 1992 to June 2010 to identify all FNA cytology and corresponding surgical specimens in which the diagnosis of PanNET was rendered or considered.

RESULTS

One hundred and thirty-two cases diagnosed by EUS-guided FNA were collected. Histological correlation was available for 77 (58%) of FNAs; 55 patients may have been treated elsewhere or had no surgery because of advanced disease or co-morbidity. Among 56 cases diagnosed as PanNET on FNA, 54 (96%) were confirmed histologically; the remaining two were poorly differentiated adenocarcinoma with focal neuroendocrine features in one case and no tumour was found in the other. Follow-up histology of nine patients diagnosed as suspicious for PanNET on FNA showed four PanNETs, two pancreatic ductal adenocarcinomas (PDA), one solid pseudopapillary tumour (SPT) and two cases of chronic pancreatitis. Nine cases rendered by FNA as atypical (n = 3), no atypical cells identified (n = 4) or unsatisfactory (n = 2) were PanNETs on histology. Lastly, three cases of oncocytic variant of PanNET were misdiagnosed on FNA as either adenocarcinoma (n = 2) or as suspicious for carcinoma (n = 1).

CONCLUSIONS

Overall, 54 of the 70 histologically confirmed PanNET cases (77%) were correctly diagnosed by preoperative FNA as PanNET. FNA cases designated as no atypical cells identified and unsatisfactory (7/132, 5%) were attributable to sampling error. Diagnostic pitfalls in our study mainly included PDA, SPT and chronic pancreatitis.

Effect of dietary cadmium on the activity of glutathione S-transferase and carboxylesterase in different developmental stages of the Oxya chinensis (Orthoptera: Acridoidea)

Glutathione S-transferases (GSTs) and carboxylesterases (CarEs) play important roles in the detoxification of endogenous and exogenous compounds. In this study, the biochemical effects of dietary cadmium (Cd) on the activities of GST and CarE in different developmental stages of the rice grasshopper Oxya chinensis Thunberg were studied. The results showed that the effects of the Cd concentration and developmental stage on GST activity were statistically significant. GST activity in O. chinensis increased at the highest Cd concentration in most nymphs, suggesting that GST is typically inducible by Cd. However, GST activity was inhibited in adults under Cd stress owing to life-stage-specific physiological characteristics. The results showed that the substrates, developmental stage, and Cd concentration had statistically significant effects on CarE activity. In most studies of CarE activity, the interaction between any two studied factors was statistically significant, although the interaction effects of the substrates, developmental stages, and Cd concentrations were not significant, which implied that the insect physiological condition and the external environmental may affect CarE activity. The results suggest that the insect's life stage and enzyme substrates should be considered when enzyme activity under Cd stress is studied.

Prenatal expression of MET receptor tyrosine kinase in the fetal mouse dorsal raphe nuclei and the visceral motor/sensory brainstem

Signaling via MET receptor tyrosine kinase (MET) has been implicated in a number of neurodevelopmental events, including cell migration, dendritic and axonal development and synaptogenesis. Related to its role in the development of forebrain circuitry, we recently identified a functional promoter variant of the MET gene that is associated with autism spectrum disorder (ASD). The association of the MET promoter variant rs1858830 C allele is significantly enriched in families with a child who has ASD and co-occurring gastrointestinal conditions. The expression of MET in the forebrain had been mapped in detail in the developing mouse and rhesus macaque. However, in mammals, its expression in the developing brainstem has not been studied extensively throughout developmental stages. Brainstem and autonomic circuitry are implicated in ASD pathophysiology and in gastrointestinal dysfunction. To advance our understanding of the neurodevelopmental influences of MET signaling in brainstem circuitry development, we employed in situ hybridization and immunohistochemistry to map the expression of Met and its ligand, Hgf, through prenatal development of the mouse midbrain and hindbrain. Our results reveal a highly selective expression pattern of Met in the brainstem, including a subpopulation of neurons in cranial motor nuclei (nVII, nA and nXII), B6 subgroup of the dorsal raphe, Barrington's nucleus, and a small subset of neurons in the nucleus of solitary tract. In contrast to Met, neither full-length nor known splice variants of Hgf were localized in the prenatal brainstem. RT-PCR revealed Hgf expression in target tissues of Met-expressing brainstem neurons, suggesting that MET in these neurons may be activated by HGF from peripheral sources. Together, these data suggest that MET signaling may influence the development of neurons that are involved in central regulation of gastrointestinal function, tongue movement, swallowing, speech, stress and mood.

Cyclophilin A and nuclear factor of activated T cells are essential in cyclosporine-mediated suppression of polyomavirus BK replication

Immunosuppressants have impacts on the development of polyomavirus-associated nephropathy. We previously demonstrated that cyclosporin A (CsA) suppressed polyomavirus BK (BKV) replication. The role of cyclophilin A (CypA) and nuclear factor of activated T cells (NFAT) in CsA-imposed suppression of BKV replication was determined in this study. Results demonstrated that knockdown of CypA but not CypB significantly reduced BKV large T antigen (TAg) expression and BKV titer. Overexpression of CypA reversed CypA siRNA-induced inhibition in BKV TAg expression. In addition, CypA overexpression attenuated the suppressive effect of CsA on TAg expression, suggesting CypA implicated in CsA-mediated anti-BKV effect. Knockdown of NFATc3 abrogated TAg expression, while overexpression of NFATc3 promoted TAg expression and augmented BKV promoter activity. NFATc3 binding to the BKV promoter was verified by chromatin immunoprecipitation assay and electrophoretic mobility shift assay. Renal histology also displayed an increase in NFATc3 expression in tubulointerstitium of BKV-associated nephropathy. Furthermore, overexpression of NFATc3 rescued CsA-mediated inhibition of BKV load and TAg expression. A CsA analog, NIM811, which cannot block NFAT functionality, failed to suppress TAg expression. In conclusion, CypA and NFAT are indispensable in BKV replication. CsA inhibits BKV replication through CypA and NFAT, which may be potential targets of anti-BKV treatment.

Activin and GDF11 collaborate in feedback control of neuroepithelial stem cell proliferation and fate

Studies of the olfactory epithelium model system have demonstrated that production of neurons is regulated by negative feedback. Previously, we showed that a locally produced signal, the TGFβ superfamily ligand GDF11, regulates the genesis of olfactory receptor neurons by inhibiting proliferation of the immediate neuronal precursors (INPs) that give rise to them. GDF11 is antagonized by follistatin (FST), which is also produced locally. Here, we show that Fst(-/-) mice exhibit dramatically decreased neurogenesis, a phenotype that can only be partially explained by increased GDF11 activity. Instead, a second FST-binding factor, activin βB (ACTβB), inhibits neurogenesis by a distinct mechanism: whereas GDF11 inhibits expansion of INPs, ACTβB inhibits expansion of stem and early progenitor cells. We present data supporting the concept that these latter cells, previously considered two distinct types, constitute a dynamic stem/progenitor population in which individual cells alternate expression of Sox2 and/or Ascl1. In addition, we demonstrate that interplay between ACTβB and GDF11 determines whether stem/progenitor cells adopt a glial versus neuronal fate. Altogether, the data indicate that the transition between stem cells and committed progenitors is neither sharp nor irreversible and that GDF11, ACTβB and FST are crucial components of a circuit that controls both total cell number and the ratio of neuronal versus glial cells in this system. Thus, our findings demonstrate a close connection between the signals involved in the control of tissue size and those that regulate the proportions of different cell types.

Glial precursors clear sensory neuron corpses during development via Jedi-1, an engulfment receptor

During the development of peripheral ganglia, 50% of the neurons that are generated undergo apoptosis. How the massive numbers of corpses are removed is unknown. We found that satellite glial cell precursors are the primary phagocytic cells for apoptotic corpse removal in developing mouse dorsal root ganglia (DRG). Confocal and electron microscopic analysis revealed that glial precursors, rather than macrophages, were responsible for clearing most of the dead DRG neurons. Moreover, we identified Jedi-1, an engulfment receptor, and MEGF10, a purported engulfment receptor, as homologs of the invertebrate engulfment receptors Draper and CED-1 expressed in the glial precursor cells. Expression of Jedi-1 or MEGF10 in fibroblasts facilitated binding to dead neurons, and knocking down either protein in glial cells or overexpressing truncated forms lacking the intracellular domain inhibited engulfment of apoptotic neurons. Together, these results suggest a cellular and molecular mechanism by which neuronal corpses are culled during DRG development.

A new Kondo antiferromagnet Ce(Ni(0.25)In(1.75))

We find that Ce(Ni(0.25)In(1.75)) crystallizes in the hexagonal AlB(2)-type structure with lattice parameters a = 0.4850(5) nm and c = 0.3908(5) nm. Magnetic susceptibility, electrical resistivity and low-temperature specific heat data reveal that the bulk phase transition at 3.7 ± 0.2 K in Ce(Ni(0.25)In(1.75)) is to an antiferromagnetic state. The magnetic contribution to the resistivity ρ(mag) of Ce(Ni(0.25)In(1.75)) increases as ln(T) when temperature is lowered from room temperature and reaches a plateau at 9 K, followed by a rapid decrease around 4 K. These results associated with a reduction of the Ce magnetic moment and of the magnetic entropy at T(N) suggest that Ce(Ni(0.25)In(1.75)) could be a Kondo antiferromagnet. The Kondo temperature is estimated to be of order 6 K.

Foxg1 promotes olfactory neurogenesis by antagonizing Gdf11

Foxg1, a winged-helix transcription factor, promotes the development of anterior neural structures; in mice lacking Foxg1, development of the cerebral hemispheres and olfactory epithelium (OE) is severely reduced. It has been suggested that Foxg1 acts by positively regulating the expression of growth factors, such as Fgf8, which support neurogenesis. However, Foxg1 also binds Smad transcriptional complexes, allowing it to negatively regulate the effects of TGFbeta family ligands. Here, we provide evidence that this latter effect explains much of the ability of Foxg1 to drive neurogenesis in the OE. We show that Foxg1 is expressed in developing OE at the same time as the gene encoding growth differentiation factor 11 (Gdf11), a TGFbeta family member that mediates negative-feedback control of OE neurogenesis. Mutations in Gdf11 rescue, to a considerable degree, the major defects in Foxg1(-/-) OE, including the early, severe loss of neural precursors and olfactory receptor neurons, and the subsequent collapse of both neurogenesis and nasal cavity formation. Rescue is gene-dosage dependent, with loss of even one allele of Gdf11 restoring substantial neurogenesis. Notably, we find no evidence for a disruption of Fgf8 expression in Foxg1(-/-) OE. However, we do observe both a failure of expression of follistatin (Fst), which encodes a secreted Gdf11 antagonist normally expressed in and around OE, and an increase in the expression of Gdf11 itself within the remaining OE in these mutants. Fst expression is rescued in Foxg1(-/-);Gdf11(-/-) and Foxg1(-/-);Gdf11(+/-) mice. These data suggest that the influence of Foxg1 on Gdf11-mediated negative feedback of neurogenesis may be both direct and indirect. In addition, defects in development of the cerebral hemispheres in Foxg1(-/-) mice are not rescued by mutations in Gdf11, nor is Gdf11 expressed at high levels within these structures. Thus, the pro-neurogenic effects of Foxg1 are likely to be mediated through different signaling pathways in different parts of the nervous system.

Gene targeting of ErbB3 using a Cre-mediated unidirectional DNA inversion strategy

Recombinase-mediated unidirectional DNA inversion and transcriptional arrest is a promising strategy for high throughput conditional mutagenesis in the mouse. Banks of mouse embryonic stem cells with defined, transcriptionally silent insertions that can be activated by Cre recombinase would take advantage of existing transgenic Cre lines to rapidly produce hundreds of lineage specific and temporally controlled knockout mice for each gene, thereby introducing significant parallelism to functional gene annotation. However, the extent to which this strategy results in effective gene knockout has not been established. To test the feasibility of this strategy we targeted ErbB3, a member of the ErbB family of tyrosine kinase receptors, using this strategy. Insertion of a reversed "flipflox" vector consisting of a gene inactivation cassette (GI) and an internal ribosome entry site (IRES)-GFP reporter into intron 1 of ErbB3 was transcriptionally silent and did not affect ErbB3 expression. Crosses with ubiquitous and lineage specific Cre recombinase expressing lines permanently inverted the inserted GI cassette and blocked ErbB3 expression. Unidirectional DNA inversion by in vivo recombination is an effective strategy for targeted or ubiquitous gene knockout.

GDF11 controls the timing of progenitor cell competence in developing retina

The orderly generation of cell types in the developing retina is thought to be regulated by changes in the competence of multipotent progenitors. Here, we show that a secreted factor, growth and differentiation factor 11 (GDF11), controls the numbers of retinal ganglion cells (RGCs), as well as amacrine and photoreceptor cells, that form during development. GDF11 does not affect proliferation of progenitors-a major mode of GDF11 action in other tissues-but instead controls duration of expression of Math5, a gene that confers competence for RGC genesis, in progenitor cells. Thus, GDF11 governs the temporal windows during which multipotent progenitors retain competence to produce distinct neural progeny.

Molecular signals regulating proliferation of stem and progenitor cells in mouse olfactory epithelium

To understand how signaling molecules regulate the generation of neurons from proliferating stem cells and neuronal progenitors in the developing and regenerating nervous system, we have studied neurogenesis in a model neurogenic epithelium, the olfactory epithelium (OE) of the mouse. Our studies have employed a candidate approach to test signaling molecules of potential importance in regulating neurogenesis and have utilized methods that include tissue culture, in situ hybridization and mouse genetics. Using these approaches, we have identified three distinct stages of stem and transit amplifying progenitor cells in the differentiation pathway of olfactory receptor neurons (ORNs) and have identified mechanisms by which the development of each of these progenitor cell types is regulated by signals produced both within the OE itself and by its underlying stroma. Our results indicate that regulation of olfactory neurogenesis is critically dependent on multiple signaling molecules from two different polypeptide growth factor superfamilies, the fibroblast growth factors and the transforming growth factor beta (TGF-beta) group. In addition, they indicate that these signaling molecules interact in at least two important ways: first, opposing signals converge on cells at specific developmental stages in the ORN pathway to regulate proliferation and differentiation; and second, these signaling molecules--particularly the TGF-betas and their antagonists--play key roles in feedback loops that regulate the size of progenitor cell pools and thereby neuron number, during development and regeneration.

Apoptosis in primary cardiac tumours

Apoptosis, or programmed cell death, is now recognised as an important cellular event during both normal development and specific disease progression. Apoptosis has been suggested to play a critical role in several cardiovascular diseases, but has not yet been identified as a major influence in primary cardiac tumours. A retrospective review of the achieved material at Chang Gung Memorial Hospital revealed seven patients with cardiac myxoma and one with a tumour originating from the crista terminalis, from January 2002 to December 2002. The medical chart, surgical pathology reports and microscopic slides were available in all cases. All patients, including eight cardiac myxomas and one tumour from crista terminalis, were assessed for apoptosis by terminal deoxynucleotidyl transferase nick-end labelling assay. In this study, apoptosis is well documented in all seven myxoma and has even been reported in tumour from the crista terminalis. Interestingly, apoptosis appears related to the nature of the cell properties rather than the incidence of embolism. In conclusion, apoptosis is important in the progression of the primary cardiac tumours, but the mechanism of cardiac tumour regression still remains uncertain.

Autoregulation of neurogenesis by GDF11

In the olfactory epithelium (OE), generation of new neurons by neuronal progenitors is inhibited by a signal from neurons themselves. Here we provide evidence that this feedback inhibitory signal is growth and differentiation factor 11 (GDF11). Both GDF11 and its receptors are expressed by OE neurons and progenitors, and GDF11 inhibits OE neurogenesis in vitro by inducing p27(Kip1) and reversible cell cycle arrest in progenitors. Mice lacking functional GDF11 have more progenitors and neurons in the OE, whereas mice lacking follistatin, a GDF11 antagonist, show dramatically decreased neurogenesis. This negative autoregulatory action of GDF11 is strikingly like that of its homolog, GDF8/myostatin, in skeletal muscle, suggesting that similar strategies establish and maintain proper cell number during neural and muscular development.

Progenitor cells of the olfactory receptor neuron lineage

The olfactory epithelium of the mouse has many properties that make it an ideal system for studying the molecular regulation of neurogenesis. We have used a combination of in vitro and in vivo approaches to identify three distinct stages of neuronal progenitors in the olfactory receptor neuron lineage. The neuronal stem cell, which is ultimately responsible for continual neuron renewal in this system, gives rise to a transit amplifying progenitor identified by its expression of a transcription factor, MASH1. The MASH1-expressing progenitor gives rise to a second transit amplifying progenitor, the Immediate Neuronal Precursor, which is distinct from the stem cell and MASH1-expressing progenitor, and gives rise quantitatively to olfactory receptor neurons. Regulation of progenitor cell proliferation and differentiation occurs at each of these three cell stages, and growth factors of the fibroblast growth factor (FGF) and bone morphogenetic protein (BMP) families appear to play particularly important roles in these processes. Analyses of the actions of FGFs and BMPs reveal that negative signaling plays at least as important a role as positive signaling in the regulation of olfactory neurogenesis.