In order to solve the problems of difficult test, high cost and long cycle in the development of large-scale airborne negative pressure isolation system, the simulation analysis of negative pressure response characteristics is carried out around various aviation conditions such as aircraft ascending, leveling and descending, especially rapid decompression, based on the computational fluid dynamics (CFD) method. The results showed that the isolation cabin could achieve -50 Pa pressure difference environment and form a certain pressure gradient. The exhaust air volume reached the maximum value in the early stage of the aircraft's ascent, and gradually decreased with the increase of altitude until it was level flying. In the process of aircraft descent, the exhaust fan could theoretically maintain a pressure difference far below -50 Pa without working; Under the special condition of rapid pressure loss, it was difficult to deal with the rapid change of low pressure only by the exhaust fan, so it was necessary to design safety valve and other anti-leakage measures in the isolation cabin structure. Therefore, the initial stage of aircraft ascent is the key stage for the adjustment and control of the negative pressure isolation system. By controlling the exhaust air volume and adjusting parameters, it can adapt to the change of low pressure under normal flight conditions, form a relatively stable negative pressure environment, and meet the needs of biological control, isolation and transport.
Aircraft ; Computer Simulation ; Aviation/instrumentation* ; Humans ; Hydrodynamics ; Air Pressure ; Equipment Design ; Pressure

Objective:To study the clinical characteristics and risk factors of necrotizing enterocolitis (NEC) in one of the premature twins.Methods:A retrospective study was conducted on twin premature infants who were admitted to the Department of Neonatology at the Third Affiliated Hospital of Zhengzhou University from January 2017 to December 2022 and only one got NEC. The twins were divided into NEC group and control group, the clinical data were collected and analyzed by SPSS 26.0 statistical software.Results:This study enrolled 109 pairs of premature twins, 109 cases in the NEC group, and 109 cases in the control group. Univariate analysis showed that birth weight, pre NEC white blood cell count were lower in NEC group than those in the control group, while the proportion of smaller than gestational age (SGA), donor of twin-to-twin transfusion syndrome, feeding intolerance, incomplete enteral feeding, start feeding time >48 h, red blood cell transfusion 72 h before NEC onset and the neutrophils ratio were higher in the NEC group than that of the control group, the difference was statistically significant ( P<0.05). Multivariate logistic analysis showed that low birth weight ( OR=1.558, 95% CI1.197-2.142), SGA ( OR=1.721, 95% CI 1.217-2.536), feeding intolerance ( OR=3.798, 95% CI 1.347-10.706), and incomplete enteral feeding ( OR=4.319, 95% CI 1.673-11.149) were independent risk factors for NEC ( P<0.05). Conclusions:Low birth weight, small for gestational age, feeding intolerance, and incomplete enteral feeding are independent risk factors for NEC in one of the premature twins.

Objective To study the sedative and hypnotic effects of Yening Capsules and investigate its bioactive mechanism in mice.Methods The mice were randomly divided into control group,estazolam group(0.8 mg/kg),low,medium and high-dose Yening Capsules groups(400,600 and 800 mg/kg).The locomotor activity,latency to persistent sleep,sleep duration and sleep rate were determined respectively in mice via the open field test and injection of pentobarbital sodium in subthreshold and suprathreshold doses.The content of GABA,5-HT,DA and NE in brain tissue of mice were detected by enzyme-linked immunosorbent assay(ELISA).Results Compared with the control group,Yening Capsules medium and high dose group(P<0.05,P<0.01)significantly decreased the locomotor activity of mice.The sleep latency in Yening Capsules medium and high dose group were significantly shorten(P<0.05,P<0.05)and the sleep duration(P<0.05,P<0.01)were extended.The sleep rate of Yening Capsules medium and high dose groups(P<0.05,P<0.01)was significantly increased.Compared with the control group,high dose of Yening Capsules can significantly increase GABA(P<0.05),5-HT(P<0.05),DA(P<0.05),NE(P<0.01)in mouse brain tissue.Conclusion Yening Capsules had obvious sedative and hypnotic effects,and its mechanism may be related to the increasement of GABA,5-HT,DA and NE level in brain tissue of mice.

Objective:To summarize the clinical and genetic characteristics of children with Menkes disease(MD).Methods:The clinical manifestations, auxiliary examinations and genetic testing results of 15 MD children admitted to the Department of Pediatrics of the Third Affiliated Hospital of Zhengzhou University, Children′s Hospital Affiliated of Zhengzhou University and the First Affiliated Hospital of Zhengzhou University from June 2016 to October 2022 were analyzed retrospectively.These children were followed up.Results:All the 15 children were male.The age at onset was ranging from 9 days to 5.5 months.White skin, curly hair, skin laxity, hypotonia and severe developmental delay were found in all children, with epilepsy in 13 children, anemia in 11 children and granulocytopenia in 4 children.The concentration of ceruloplasmin in the serum of MD children was lower than that in healthy children of the same age.The concentration of ceruloplasmin in MD children younger than 3 months was significantly lower than that in healthy children of the same age and MD children older than 3 months.The brain magnetic resonance imaging showed abnormalities in all 15 children.Twelve children showed tortuous intracranial vessels in brain magnetic resonance angiography examinations.All the 15 children had ATP7A gene pathogenic variants, including 4 missense variants(2 cases with c. 2179G>A), 3 frameshift variants, 3 nonsense variants, 3 exon deletions and 2 splice site variants.Among these children, 1 had a novel gene variant that had not been reported so far(c.2968C>T). Conclusions:MD has early onset age and diverse clinical manifestations, but also has characteristic clinical manifestations and applicable auxiliary examinations.Its diagnosis depends on genetic testing.The c. 2179G>A and exon deletions may be hot mutations in Chinese MD patients.

Objective This article aimed to explore the inhibitory effect of β-ionone(BI)on the proliferation of breast canc-er cells through the nuclear factor kappa-B(NF-κB)pathway and its possible mechanism.Methods The methylene blue assay and MTT assay were used to determine the viability of breast cancer cells.The malachite green phosphate assay was used to detect the ac-tivity of protein phosphatase 2A(PP2A).Western blot was used to detect the levels of phosphorylated P65(s534 and s311)(p-P65),PP2A(A,B and C),and phosphorylated ataxia telangiectasia mutant(p-ATM)(s1981)protein.Results BI could significant-ly inhibit the proliferation of human breast cancer BT549 cells and MCF-7 cells in a time-and dose-dependent manner,and the difference was statistically significant(P<0.01).After treated with BI,NF-κB activity was significantly inhibited in MCF-7 cells,as shown by a significant decrease in the level of phosphorylated P65(s311 and s534)protein and an increase in the level of PP2A pro-tein,and the difference was statistically significant(P<0.05).In addition,BI also significantly reduced the phosphorylation of P65 protein and ATM protein in MCF-7 cells by the PP2A inhibitor-okada acid(OA).Conclusion This study shows that BI inhibits the proliferation of breast cancer cells by inhibiting NF-κB activity,and its mechanism may be achieved by increasing PP2A activity to regulate the NF-κB pathway.

In order to detect the environmental data of isolated cabin under various environmental conditions,a negative pressure cabin environment detector for aviation was developed,which was composed of a shell,a differential pressure transmitter,a pressure sensor,a carbon dioxide concentration sensor,an oxygen concentration sensor,a temperature and humidity sensor,a data processing module,a liquid crystal display(LCD)screen and USB data interface.It could environmental data such as carbon dioxide concentration,oxygen concentration,temperature,humidity,pressure difference between cabin and outside the cabin and air pressure outside the cabin in real time,the data processing module collected and processed the data,the data and data change curves was displayed in real time by the LCD screen,and the detection data was extracted through the USB data interface.When used in aviation environment,the detector could work continuously without fault for no less than 300 hours,and the average fault repair time was about 30 minutes,with good performance and high detection accuracy,which can provide convenience for the environmental data detection of negative pressure cabins,and is worthy of popularization.

Objective:To study the clinical characteristics and imaging features of neonatal ovarian cysts and to analyze treatment and prognosis of ovarian torsion.Methods:From January 2011 to December 2021,neonates with ovarian cysts admitted to the department of neonatology and pediatric surgery of our hospital were retrospectively studied. They were assigned into ovarian torsion group and non-torsion group. Their clinical manifestations, imaging features, pathological results, treatment and prognosis were reviewed and compared.Results:A total of 44 neonates with ovarian cysts were included, all without specific clinical manifestations. 10 neonates were treated with conservative therapy and 34 received surgery. Ovarian torsion were confirmed during surgery in 23 patients. All 34 patients received abdominal ultrasound preoperatively and 31 (91.2%, 31/34) were diagnosed with ovarian cysts. The accuracy rates of ultrasound for cyst location and ovarian torsion were 85.3% (29/34) and 82.6% (19/23),respectively. 30 patients received abdominal CT scan and 23 (76.7%, 23/30) were diagnosed with ovarian cysts. The accuracy rates of CT scan for cyst location and ovarian torsion were 53.3% (16/30) and 47.8% (11/23), respectively. Among the 34 patients treated with surgery, ovarian cyst dissection was performed in 11 patients and cyst resection in 23 patients with torsion necrosis. 24 patients had simple cysts including 15 torsion necrosis (62.5%, 15/24) and 10 had complicated cysts including 8 torsion necrosis(80.0%, 8/10). The average diameter of ovarian cysts was significantly larger in the torsion group [(8.4±1.6) cm] than the non-torsion group [(4.7±1.2) cm] ( P<0.05). Conclusions:Neonatal ovarian cysts are mostly unilateral without specific clinical manifestations. Large, bilateral and complex cysts are prone to torsion necrosis. Abdomen ultrasound has advantages than CT scan for the localization of the ovarian cyst and diagnosis of ovarian torsion. Surgical treatment is necessary after diagnosis.

Objective:To study the effects of recombinant human erythropoietin (rhEPO) on cerebral blood flow (CBF) in preterm infants using arterial spin labeling (ASL) magnetic resonance imaging (MRI).Methods:From September 2021 to June 2022, preterm infants (gestational age ≤32 weeks, birth weight ≤1 500 g) admitted to NICU of our hospital within 24 h after birth were randomly assigned into rhEPO group and control group for this prospective study. The rhEPO group was given rhEPO (500 IU/kg iv, once every other day for 2 weeks) within 72 h after birth plus symptomatic supportive treatment. The control group received same amount of normal saline injection. Both groups received brain MRI, diffusion-weighted imaging and ASL at adjusted gestational age of 35~37 weeks and CBF values of interested areas were measured.Results:A total of 85 infants were enrolled, including 40 in the rhEPO group and 45 in the control group. No significant differences existed in the incidences of periventricular-intraventricular hemorrhage, periventricular leukomalacia, focal white matter injury and extensive white matter injury between the two groups ( P>0.05). The CBF values [ml/(100 g·min)] of frontal cortex [left 15.1±3.9 vs. 17.9±3.1, right 15.9 (12.5, 17.8) vs. 18.1(16.1,20.2)], temporal cortex [left 15.8±4.3 vs. 18.6±3.8, right 16.3(13.2,19.4) vs. 18.1(15.7,19.7)], occipital cortex (left 15.8±6.1 vs. 18.8±3.3, right 16.8±5.5 vs. 19.3±4.8), basal ganglia (left 24.7±7.2 vs. 28.7±6.2, right 26.0±7.9 vs. 29.3±6.4) and thalamus (left 32.7±11.8 vs. 37.9±8.6, right 32.1±11.6 vs. 37.6±10.2) in the rhEPO group were significantly lower than the control group ( P<0.05). No significant differences existed of CBF value at the parietal cortex between the two groups ( P>0.05). Conclusions:Early application of rhEPO can reduce CBF in premature infants, which may be related to the neuro-protective effects of EPO.

Objective:To study the current status of critical neonatal care centers (CNCC) construction and treatment of critically-ill neonates at city- and county-level in Henan Province.Methods:A questionnaire survey was conducted in January 2022 to city- and county-level CNCC in Henan Province. The basic information of CNCC, ward settings, neonatal management in the Department of Obstetrics and the treatment of critically-ill neonates in 2019-2021 were analyzed.Results:A total of 188 questionnaires were sent and 183 (97.3%) eligible questionnaires were analyzed, including 30 from city centers and 153 from county centers. The bed occupancy rate in county centers was significantly lower than city centers (67.3%±24.1% vs. 86.1%±23.2%), and the doctor/bed ratio, doctor/rescue bed ratio and nurse/rescue bed ratio were significantly higher than city centers ( P<0.05). All city centers had set up independent Department of Neonatology and the number is 92.8% (142/153) in county center. For 80.9% (148/183) centers, neonates were managed in the Department of Obstetrics with consultations and referrals to the Department of Pediatrics and 19.1% (35/183) were managed in the Department of Pediatrics/Neonatology. The average number of deliveries and admissions to the Department of Neonatology in both city and county centers decreased year on year during 2019-2021, but the proportion of premature and low/very low birth weight infants treated in these centers increased year on year. During 2019-2021, the top three diseases treated at the city centers were neonatal respiratory distress syndrome, neonatal asphyxia and acute respiratory distress syndrome, while the top three diseases treated at the county centers were neonatal asphyxia, neonatal respiratory distress syndrome and meconium aspiration syndrome. The incidence of sudden infant death syndrome in city and county centers was (10~30)/100,000. Conclusions:The construction of CNCC in Henan Province is facing challenges such as decreased hospital admissions, increased critically-ill neonates, insufficient cooperation between Obstetrics and Pediatrics and waste of resources. Rationally allocated and optimised use of resources to improve the ability to treat critically-ill neonates is warranted.

Objective:To summarize the clinical manifestations of a case of combined oxidative phosphorylation deficiency 28 (COXPD-28) caused by the mutations of the SLC25A26 gene, thus providing references for the diagnosis and genetic counseling of the disease. Methods:Clinical data of a case of COXPD-28 treated in the Third Affiliated Hospital of Zhengzhou University in October 2020 were retrospectively analyzed.In addition, The retrieval words " Combined oxidative phosphorylation deficiency 28, SLC25A26 gene" were used to search domestic and foreign databases.The clinical characteristics of combined phosphorylation deficiency 28 and the variation characteristics of SLC25A26 gene were summarized. Results:(1) A female patient full-term delivered after 30 min presented with groaning breath was admitted.Her main manifestations included pale complexion, groaning breathing, metabolic acidosis, and high lactate and pyruvate levels.Symptomatic support treatment like anti-infection and assisted ventilation were given, but her condition gradually worsened and died of respiratory and circulatory failure on the day of admission.The child was compound heterozygous mutation of SLC25A26 gene, the terminating mutation of exon 5 c. 403G>T caused the protein change to p. E135, and the non-synonymous mutation of exon 4 c. 212A>G caused the protein change to p. Y71C.(2) A total of 3 cases of COXPD-28 were searched in online databases, and no cases were reported in China.Through literature review, clinical features of COXPD-28 mainly included respiratory and circulatory fai-lure, elevations of lactate and pyruvate, and reductions of complexes Ⅰ, Ⅲ and Ⅳ in muscle biopsy.Two types of mutations in the SLC25A26 gene were detected, including 3 cases of missense mutations and 1 case of splicing mutation. Conclusions:COXPD-28 is an autosomal recessive genetic disease involving multiple systems and mitochondrial dysfunction.Mutations in the SLC25A26 gene is the pathological cause of COXPD-28.