AIM: To investigate the current status of retinopathy of prematurity(ROP)in premature infants in Xiamen and analyze its influencing factors, aiming to provide a scientific basis for clinical treatment and preventive strategies.METHODS: A retrospective study was conducted on the case data of 363 preterm infants with a gestational age of <32 wk who underwent fundus examination at Xiang'an Hospital of Xiamen University from February 11, 2020 to February 25, 2023. The incidence of ROP was statistically analyzed based on the screening results. All premature infants were divided into ROP group(37 cases, 64 eyes)and non-ROP group(326 cases, 652 eyes). General clinical data and perinatal-related information of the two groups were compared, and multivariate Logistic regression analysis was used to identify factors influencing the occurrence of ROP in premature infants.RESULTS: A total of 363 premature infants were included in this study. The fundus screening results showed that a total of 37 cases(64 eyes)of premature infants were detected with ROP, including 10 cases(10 eyes)monocular and 27 cases(54 eyes)binocular, with an overall incidence of 10.2%(37/363). The severity was determined according to the ROP international classification standard(ROP is divided into 5 stages, with stage I being the least severe and stage V the most severe). Among the 64 eyes, 30 eyes(46.9%)were in stage I, 20 eyes(31.3%)were in stage II, 10 eyes(15.6%)were in stage III, 4 eyes(6.3%)were in stage IV, and there were no cases in stage V. By comparing the clinical data of the two groups, no significant differences were found in gender, mode of delivery, singleton or multiple births, premature rupture of membranes, history of asphyxia, patent ductus arteriosus(PDA), or neonatal respiratory distress syndrome(NRDS)between the two groups(all P>0.05). However, premature infants in the ROP group had significantly younger gestational age and lower birth weight compared to those in the non-ROP group(all P<0.05). Additionally, the ROP group had higher proportions of longer hospital stays, bronchopulmonary dysplasia(BPD), neonatal sepsis, anemia, oxygen therapy for more than 1 wk, oxygen concentration above 40%, and blood transfusion treatment(all P<0.05). Multivariate Logistic regression analysis revealed that combined neonatal sepsis(OR=166.985, 95% CI: 35.239-791.277, P<0.001), anemia(OR=8.111, 95% CI: 2.064-31.871, P=0.003), oxygen use time >1 wk(OR=10.216, 95% CI: 2.543-41.039, P=0.001), oxygen therapy concentration >40%(OR=7.647, 95% CI: 1.913-30.566, P=0.004), and receiving blood transfusion therapy(OR=5.879, 95% CI: 1.412-24.470, P=0.015)were the main risk factors affecting the occurrence of ROP in preterm infants, and the higher birth weight of preterm infants was a protective factor for ROP(OR=0.093, 95% CI: 0.022-0.394, P=0.001).CONCLUSION: The incidence of ROP in premature infants is relatively high, and there are multiple influencing factors. Low birth weight, neonatal sepsis, anemia, oxygen therapy, and blood transfusion treatment are high-risk factors for ROP in premature infants. Clinical attention should be given to such infants, and fundus screening should be conducted in a standardized manner to provide early treatment, thereby further reducing the risk of ROP in premature infants.

Motion sickness refers to a multi-system physiological syndrome caused by abnormal acceleration and motion vision scene immersion.It occurs commonly in transportation,military operations,space exploration and other fields.This article reviews recent advances in mechanism,prediction and assessment as well as control measures for motion sickness,and discusses possible research direction of motion sickness in the future.The biological basis for motion sickness sensory conflict theory has been expanded;genomic sequencing and artificial intelligence techniques have been used as novel tools for motion sickness prediction and evaluation.Acclimatization training,anti-motion sickness medication and non-drug symptom control measures used in combination is the key for motion sickness prevention and treatment.

Objective To observe the changes of plasma gastrointestinal hormones in motion sickness sensitive and insensitive individuals before and after vertical oscillation stimulation,and to construct a susceptibility prediction model for motion sickness.Methods A total of 60 healthy male volunteers were enrolled to receive sinusoidal vertical oscillation stimulation for 45 min.The motion sickness susceptibility questionnaire(MSSQ)was filled out before the experiment.Immediately after motion,the severity of motion sickness was evaluated by Graybiel scale.The motion sickness sensitive(Graybiel score≥8 and MSSQ susceptibility index＞21,n=15)and insensitive(Graybiel score≤2 and MSSQ susceptibility index＜5,n=15)participants were screened.Plasma levels of glucagon-like peptide-1(GLP-1),cholecystokinin(CCK),leptin,ghrelin,neuropeptide Y(NPY)and orexin A(OXA)were detected by enzyme-linked immunosorbent assay before and after vertical oscillation stimulation.Logistic regression model was used to analyze the predictive effect of plasma gastrointestinal hormone levels on susceptibility to motion sickness,and a combined predictive model was established.Receiver operating characteristic(ROC)curve was used to analyze predictive value of the model.Results Ghrelin and CCK levels were significantly increased in the sensitive group after stimulation compared with those before stimulation(both P＜0.01),while NPY and leptin levels were significantly decreased(both P＜0.01).Similar results were also observed when compared with the insensitive group after stimulation.Multivariate logistic regression analysis showed that plasma ghrelin,CCK and NPY were independent predictors of susceptibility to motion sickness.The established susceptibility prediction model for motion sickness was logit(P)=-0.051 ×ghrelin+0.060× NPY-0.169 ×CCK+33.397.ROC curve analysis showed that area under curve(AUC)value of the prediction model was 0.988,the sensitivity and specificity were 100.0％and 93.3％,respectively,and the prediction effect was better than ghrelin,CCK and NPY alone(AUC=0.792,0.880,0.838).Conclusion The changes of peripheral gastrointestinal appetite regulating hormone levels may be related to the susceptibility to motion sickness.The combined use of these indicators can predict the susceptibility to motion sickness.

Objective To explore the improving effects of motion sickness acclimatization training methods,namely sinusoidal vertical oscillation stimulation and sinusoidal vertical oscillation stimulation combined with visual virtual reality(VR)swell stimulation,on cognitive performance of individuals with extremely severe motion sickness.Methods A total of 90 individuals with extremely severe motion sickness screened by the Graybiel score during 6 h navigation were randomly divided into vertical group,vertical+VR group,and control group(n=30).The abilities of vigilance,memory,rapid calculation,information processing and visual manipulation were evaluated before and after the acclimatization training using a self-developed cognitive performance evaluation software.Results On the 1st day of training,the numbers of missed targets of the vertical group and vertical+VR group were increased in the vigilance test;the reaction time was prolonged in the short-term memory,rapid calculation,information processing and visual manipulation tasks;and the efficiency of rapid calculation was reduced.After acclimatization training,the numbers of missed targets were reduced to the baseline level in the vertical and vertical+VR groups,and the reaction time in the short-term memory,rapid calculation,information processing and visual manipulation tasks and the efficiency of rapid calculation were improved.Conclusion Motion sickness caused by vertical oscillation stimulation or vertical oscillation combined with visual VR swell stimulation can decrease vigilance,short-term memory,rapid calculation,information processing and visual manipulation abilities.Motion sickness acclimatization training can significantly improve the above cognitive abilities.

Objective To study the acclimatization time and effects for preventing motion sickness under sinusoidal vertical oscillation stimulation,visual virtual reality(VR)swell stimulation,and their combined stimulation.Methods Totally 120 individuals with extremely severe motion sickness during 6 h navigation were randomly divided into 4 groups(n=30):vertical group,VR group,vertical+VR group,and control group.The severity of symptoms during the training period was assessed daily by Graybiel scale,and the number of drops from flexible treadmill in the VR group was recorded.The Graybiel score of 0 for 3 d and/or the number of drops for 0 were considered as complete acclimatization.The training effect was validated by navigation under more severe sea conditions.Results The Graybiel scores of the vertical group and vertical+VR group,as well as the number of drops of the VR group were decreased with the increase of training days,and reached the acclimatization level on the 3rd,5th,and 2nd training day,respectively.The longest acclimatization time in the vertical,vertical+VR,and VR groups was 8,8,and 5 d,with an average acclimatization time of 3.6,3.9,and 2.7 d,respectively;the acclimatization rates within 5 d were 93.33％(28/30),76.67％(23/30),and 100.00％(30/30),respectively;the proportions of individuals with effective acclimatization training in the verification voyage were 86.67％(26/30),96.67％(29/30),and 66.67％(20/30),respectively;and the training efficiency was 85.19％,96.30％,and 62.97％,respectively.Conclusion Three training methods all have effects on motion sickness acclimatization,and the acclimatization period is 5-8 d.The acclimatization effects of the vertical oscillation and vertical oscillation+VR training are better than the VR training.

Objective To observe the effect of the supine-posture ripple wood training in preventing motion sickness caused by linear acceleration.Methods Totally 61 motion sickness sensitive males were screened by a vertical oscillation simulator and divided into mildly sensitive group(Graybiel score 1-15,n=28)and severely sensitive group(Graybiel score 16,n=33).The participants in the 2 groups received 5-d ripple wood training,30 min/d.The movement frequency of the ripper wood was maintained at 0.25-0.35 Hz,with an acceleration of 0.15-0.25 g.Graybiel score during the training period was recorded.The static balance function test was conducted before and after training on the 1st and 5th day.Results During the training period,the Graybiel scores and motion sickness incidence in the severely sensitive group were decreased with the increase of training days,and all participants achieved complete acclimatization on the 4th day.The Graybiel scores of the mildly sensitive group were low during the whole period,and the complete acclimatization period was 2 d.There was no significant difference in the sway area of the severely sensitive group in static balance function test before and after training(P＞0.05).The mean velocity of the severely sensitive group in static balance function test was significantly increased after training versus before training on the 1st day(P＜0.01),and there was no significant difference before and after training on the 5th day(P＞0.05).There were no significant differences in the sway area or mean velocity of the mildly sensitive group during the whole training period(all P＞0.05).The validation experiment showed that the motion sickness incidence and the symptom severity were significantly decreased in both groups;the motion sickness incidence of the mildly sensitive group decreased from 100.00％(28/28)to 35.71％(10/28);the incidence of severe symptoms in the severely sensitive group decreased from 100.00％(33/33)to 6.06％(2/33)and the vomiting incidence decreased from 96.97％(32/33)to 6.06％(2/33).Conclusion The supine-posture ripple wood training has great effect in preventing motion sickness,with widespread use and simple operation.

Objective To observe the distribution characteristics of motion sickness susceptibility and compare the efficacy of modified motion sickness susceptibility questionnaire(MSSQ),motion sickness history questionnaire and Graybiel scale in evaluating motion sickness.Methods The susceptibility to motion sickness and historical symptoms were investigated using MSSQ and motion sickness history questionnaire among 1 661 males in navy units A,B,and C.A total of 389 people from the unit C were selected for simulating vertical oscillation stimulation,and the severity of motion sickness was evaluated by Graybiel scale during the stimulation process.The evaluation efficacy of MSSQ,motion sickness history questionnaire and Graybiel scale for motion sickness was analyzed by receiver operating characteristic(ROC)curves.Results The overall distribution of motion sickness susceptibility assessed by MSSQ and motion sickness history questionnaire in this population was right skewed.The distribution characteristics in the units A,B,and C were consistent with the overall distribution,and there was no significant difference among the 3 units.A positive correlation was observed between the MSSQ and the motion sickness history questionnaire in the units A,B,and C(rs=0.565,0.565,0.554),and both of them were comparable in assessing the incidence of motion sickness and severe motion sickness.However,the incidence of motion sickness assessed by Graybiel scale was significantly lower than that assessed by MSSQ and motion sickness history questionnaire(both P＜0.05),and the incidence of severe motion sickness was significantly higher than that assessed by MSSQ and motion sickness history questionnaire(both P＜0.05).ROC curve analysis showed that MSSQ had good predictive value for motion sickness susceptibility and severe motion sickness(area under curve[AUC]=0.736,0.750),while the Graybiel scale had poor predictive ability(AUC=0.559,0.557).Conclusion The right skewed distribution of susceptibility to motion sickness is preliminarily determined.During the acclimatization training for motion sickness,the susceptible individuals can be screened by MSSQ and then subjected to vertical oscillation stimulation to improve the training efficiency.

Objective:To analyze clinical and imaging features of Sturge-Weber syndrome in children.Methods:Clinical data were collected from 27 children with Sturge-Weber syndrome in Xuzhou Children′s Hospital, Xuzhou Medical University from July 2013 to December 2019, and analyzed retrospectively.Results:Among the 27 children, 17 were males and 10 were females. Their age at the clinic visit ranged from 2 days to 10 years and 7 months, and averaged 2.54 years. All the 27 patients presented with facial port-wine stains of varied color from light red to purple red, which were all distributed across the facial midline, including 21 with predominantly unilateral port-wine stains and 6 with bilateral symmetrical port-wine stains. There were 17 patients with ocular choroidal vascular malformations, including 14 with congenital glaucoma, 5 with high intraocular pressure, and 1 with optic nerve atrophy accompanied by transient blindness. Neurological impairment occurred in 12 patients, and all manifested as epilepsy. All the 27 children underwent imaging examination, and abnormalities were found in 20. Among the 10 patients with abnormal computed tomography images, local calcification was observed in 8, and local thickening of the skull on the side affected by skin lesions in 8; 13 of 14 patients with abnormal magnetic resonance imaging scan results had signs of brain atrophy, 9 showed enhanced gyrus-like blood vessel formation by enhanced magnetic resonance imaging, and 5 showed decreased branches of the anterior and middle cerebral artery on the affected facial side by magnetic resonance angiography.Conclusions:Children with Sturge-Weber syndrome are clinically characterized by predominantly unilateral port wine stains on the face, some of whom are accompanied by epilepsy, glaucoma or mental retardation, and imaging examinations mainly show local calcification, brain atrophy, local thickening of the skull plate, enhanced gyrus-like blood vessel formation, etc. Early definite diagnosis and comprehensive systemic treatment are needed to reduce disability and mortality rates in patients with Sturge-Weber syndrome, and long-term follow-up should be considered.

Objective To study the relationship of serum 25-hydroxy vitamin D [25-(OH) D] and vitamin D binding protein (DBP) in premature infants with bronchopulmonary dysplasia (BPD) and their clinical significance.Method From March 2017 to September 2018,the premature infants with gestational age (GA)＜32 weeks admitted to the neonatal department of our hospital were prospectively studied.All the premature infants were given 800 IU/d vitamin D supplement from one week after birth.Venous blood sample were collected at birth and 28 d after birth to measure 25-(OH) D aud DBP levels.The infants were evaluated for BPD at 28 d after birth and then assigned into the BPD group and the non-BPD group.The differences of 25-(OH) D and DBP levels were compared.Result A total of 170 premature infants (GA＜32 weeks) were included,including 56 cases in the BPD group and 114 cases in the non-BPD group.The BPD group had 34 males,the GA was (29.8±1.2) weeks,the birth weight (BW) was (1 198± 157) g.The non-BPD group had 95 males,the GA was (30.2± 1.5) weeks,the BW was (1 243± 146) g.No significant differences existed in GA,BW and male gender proportion between BPD group and non-BPD group (P＞0.05).The BPD group had a lower levels of serum 25-(OH) D at birth [(27.8±5.9) nmol/L vs.(30.4±1.1) nmol/L,P＜0.05].The levels of serum 25-(OH) D in moderate/severe BPD group were significantly lower than mild BPD group [(25.3±4.9) nmol/L vs.(29.7±5.9) nmol/L,P＜0.05];25-(OH) D in BPD group was still lower than the non-BPD group at 28 days after birth (after vitamin D supplement) [(77.5±11.7) nmol/L vs.(83.8±11.6) nmol/L,P＜0.05].Comparison of serum DBP levels between the two groups showed that,DBP at 28 d after birth in BPD group were significantly lower than the non-BPD group,and DBP in moderate/severe BPD group were significantly lower than the mild BPD group [(373.9± 19.1) μg/ml vs.(391.4±23.6) μg/ml],the differences were both statistically significant (P＜0.05).Multivariate analysis showed that the high serum 25-(OH)D level at birth (OR=0.827,95％CI0.693～0.987) was protective factors for BPD,while neonatal pneumonia (OR=4.331,95％CI 1.269～14.784) and neonatal sepsis (OR=4.020,95％CI 1.153～14.015) were risk factors for BPD.Conclusion The high serum 25-(OH) D level at birth in preterm infants was protective factors for BPD,while neonatal pneumonia and sepsis were the risk factors for BPD.Moreover,low serum 25-(OH) D level at birth and low serum DBP level at 28 d after birth maybe useful indicators for the severity of BPD.

Objective This paper was performed to investigate the effectiveness of problem-based learning in naval hygiene teaching. Methods Totally 257 clinical medicine undergraduates and general practice undergraduates from Grade 2010 and 2009, Faculty of Naval Medicine, Second Military Medical University attended naval hygiene teaching. PBL and LBL approaches were applied in PBL group (Grade 2010, n=117) and LBL group (Grade 2009, n=140), respectively. The learning outcomes were evaluated by three tests covering PBL evaluation (or usually performance), theoretical examination and experimental practice . Questionnaire was used to investigate the recognition of PBL teaching method and new evaluation system. Data were analyzed by SPSS 16.0 and t test was used to compare the average scores of theory,α=0.05. Results The results showed that the average theory scores of Grade 2010 (78.51±7.57 and 71.68±5.74) were higher than those of Grade 2009 (65.36±6.41 and 59.97±7.08) (P=0.000, P=0.000). The questionnaire surveys indicated that more than 85% students in PBL group considered the PBL teaching method could enhance professional and comprehensive quali-ties, and that 84%students were satisfied with new evaluation system. Conclusions PBL showed better learning results than traditional methods in naval hygiene teaching and could better promoted students' comprehensive ability.