[Association of FokI rs2228570 and TMPRSS6 rs855791 polymorphisms with cow's milk protein allergy in children].

OBJECTIVE: To study the association of polymorphisms of FokI rs2228570 in the vitamin D receptor (VDR) gene and TMPRSS6 rs855791 with cow's milk protein allergy (CMPA) in children. METHODS: Quantitative real-time PCR was used to analyze the single nucleotide polymorphisms of FokI rs2228570 in the VDR gene and TMPRSS6 rs855791 in 100 children with CMPA and 100 healthy children (control group). The multivariate logistic regression model was used to identify the risk factors for CMPA. RESULTS: There were significant differences in the frequencies of CC, CT, and TT genotypes of TMPRSS6 rs855791 between the CMPA and control groups (P=0.008), and the CMPA group had a significantly higher frequency of TT genotype. The multivariate logistic regression analysis showed that the children with TT genotype of rs855791 had an increased risk of CMPA (OR=3.473, P=0.011). However, there was no significant difference in the genotype distribution of FokI rs2228570 in the VDR gene between the two groups (P=0.686). CONCLUSIONS: TMPRSS6 rs855791 polymorphism is associated with CMPA in children, and TT genotype may be the susceptible genotype of CMPA. FokI rs2228570 polymorphism is not associated with CMPA.

Anaesthesia modalities during laser photocoagulation for retinopathy of prematurity: a retrospective, longitudinal study.

OBJECTIVES: Laser photocoagulation surgery is a routine treatment for threshold retinopathy of prematurity (ROP). However, little is known about which anaesthesia protocols provide efficient pain control while minimising exposure risk to vulnerable infants. In this study, therefore, we assessed the efficacy and tolerability of multiple anaesthesia techniques used on premature infants during laser therapy. DESIGN AND MAIN OUTCOME MEASURES: Anaesthesia modalities consisted of topical eye drops anaesthesia, general anaesthesia and intravenous fentanyl sedation with mechanical ventilation. Laser treatment efficacy and detailed operative information were retrospectively and consecutively analysed. Cardiorespiratory stability was assessed and compared. The Neonatal Pain Agitation and Sedation Scale (N-PASS) was used to evaluate tolerability in infants that underwent intravenous fentanyl sedation. RESULTS: 97 cases of prematurity were included in this study. In 94/97 (96.9%) cases, vascular proliferation regressed. In the topical anaesthesia groups, the ophthalmologist needed 12-16 min more to complete the treatment. During the 3 postoperative days, topical anaesthesia demonstrated the greatest instability; 4/31 (12.90%) infants in this group suffered from life threatening events requiring resuscitation. The only instability observed in general anaesthesia and fentanyl sedation was attributed to difficulty in extubating within 24 hours after surgery. During laser therapy, the N-PASS score increased to 1.8 in the fentanyl sedation group. CONCLUSIONS: Topical anaesthesia was associated with more cardiorespiratory instability during ROP laser treatment. While general anaesthesia and fentanyl sedation had similar postoperative cardiorespiratory results, the latter demonstrated acceptable pain stress control. However, the difficulty of weaning off mechanical ventilation in some cases after surgery needs to be addressed in future studies.

Systemic changes and adverse effects induced by retinopathy of prematurity screening.

AIM: To estimate the potential systemic events during and after retinopathy of prematurity (ROP) screening. METHODS: A prospective and descriptive designed study was conducted to detect the physiologic and pathological changes 24h before, during, and 72h after ROP screening. Control blood pressure (BP), saturation, pulse rate, and body temperature were routinely taken at various time internals before and after screening. Adverse effects pertain to cardiovascular system, respiratory system, gastric system, urinary system and nervous system were retrospect 0-72h after ROP screening at a 24-hour interval. RESULTS: Totally 1254 prematurity babies receiving ROP screening during Jan. 1(st) 2013 to Dec. 31(th) 2013 were enrolled in our survey. Compared to control vital sign data taken before the examination, there was a fluctuation in the diastolic BP with the increased 3.03 mm Hg (P=0.04) after 3 doses of mydriatic drops. Immediately after the examination, there was a further 12.64 mm Hg (P<0.01) increase in systolic BP and a 7.24 mm Hg (P<0.01) in diastolic BP. The mean pulse rate during examination was 22.4 bpm (P<0.01) higher than the 133.3±9.0 bpm control level. The oxygen saturation shared an average drop of 5% (P<0.01) during screening. In prematurity with postconceptional age less than 31wk, the incidence of apnea (23.5%), necrotizing enterocolitis (NEC) (8.7%), gastric residual (25.4%) and upper digestive tract hemorrhage (6.4%) also demonstrated a significant rise (P<0.01). CONCLUSION: In our study sample, ROP screening was associated with NEC, gastric residual and upper digestive tract hemorrhage. These gastrointestinal side effects, along with breath activity pattern change and vital signs indicators fluctuation, may be results of additional stress responses.

[Evaluation of white matter myelination in preterm infants using DTI and MRI].

OBJECTIVE: To investigate the features of white matter myelin development in preterm infants using magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). METHODS: A total of 31 preterm infants with a gestational age of ≤32 weeks and a birth weight of <1 500 g were enrolled. According to head MRI findings, these infants were divided into preterm group with brain injury (12 infants) and preterm group without brain injury (19 infants). A total of 24 full-term infants were enrolled as control group. Head MRI and DTI were performed at a gestational age or corrected gestational age of 37-40 weeks. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were measured for the same regions of interest in the three groups. RESULTS: The preterm group with brain injury showed a significantly lower FA value of the posterior limb of the internal capsule than the preterm group without brain injury and full-term control group (P<0.05). The preterm groups with and without brain injury showed significantly lower FA values of frontal white matter and lenticular nucleus than the full-term control group (P<0.05). The FA value of occipital white matter showed no significant differences among the three groups (P>0.05). Compared with the full-term control group, the preterm groups with and without brain injury showed significantly higher ADC values of the posterior limb of the internal capsule, lenticular nucleus, occipital white matter, and frontal white matter (P<0.05). CONCLUSIONS: After brain injury, preterm infants tend to develop disorder or delay of white matter myelination in the posterior limb of the internal capsule. At a corrected full-term gestational age, the preterm infants with and without brain injury have a lower grade of maturity in periventricular white matter and grey matter than full-term infants.

Identification of Iron Homeostasis Genes Dysregulation Potentially Involved in Retinopathy of Prematurity Pathogenicity by Microarray Analysis.

Retinopathy of prematurity (ROP) is a serious disease of preterm neonates and there are limited systematic studies of the molecular mechanisms underlying ROP. Therefore, here we performed global gene expression profiling in human fetal retinal microvascular endothelial cells (RMECs) under hypoxic conditions in vitro. Aborted fetuses were enrolled and primary RMECs were isolated from eyeballs. Cultivated cells were treated with CoCl2 to induce hypoxia. The dual-color microarray approach was adopted to compare gene expression profiling between treated RMECs and the paired untreated control. The one-class algorithm in significance analysis of microarray (SAM) software was used to screen the differentially expressed genes (DEGs) and quantitative RT-PCR (qRT-PCR) was conducted to validate the results. Gene Ontology was employed for functional enrichment analysis. There were 326 DEGs between the hypoxia-induced group and untreated group. Of these genes, 198 were upregulated in hypoxic RMECs, while the other 128 hits were downregulated. In particular, genes in the iron ion homeostasis pathway were highly enriched under hypoxic conditions. Our study indicates that dysregulation of genes involved in iron homeostasis mediating oxidative damage may be responsible for the mechanisms underlying ROP. The "oxygen plus iron" hypothesis may improve our understanding of ROP pathogenesis.

[Clinical study of astragalus's preventing the recurrence of asthma in children].

OBJECTIVE: To study the clinical efficacy of astragalus's preventing the recurrence and regulatory effects on Th1/Th2 cytokines in asthmatic children during the remission stage. METHODS: Ninety asthmatic children during the remission stage were assigned to the astragalus treatment group (Group A), the hormone treatment group (Group B), and the combined group of astragalus and hormone treatment (Group C), 30 in each. Thirty healthy children were set up as the control group. The changes of peak expiratory flow rate (PEFR) before and after treatment and the recurrence times during the one-year follow-up were observed. Peripheral serum contents of immunoreactive fibronectin-gamma (IFN-gamma) and interleukin-4 (IL-4) were detected before and after treatment using ELISA. RESULTS: The total effective rate was higher in Group B (73.3%) than in Group A (66.7%), but with no statistical difference between the two groups (P>0.05). It was highest in Group C (96.7%), showing significant difference from the other two groups (P<0.05). The levels of PEFR and IFN-gamma significantly increased and IL-4 obviously decreased in the three groups after treatment (P<0.05). No statistical difference of PEFR, IFN-gamma, or IL-4 existed in the three groups before treatment (P>0.05). Statistical difference of PEFR, IFN-gamma, or IL-4 existed between Group C and Group B after treatment (P<0.05). CONCLUSIONS: Astragalus played a role in preventing the recurrence of asthma. The combination of astragalus and hormones showed better effects.

[Effect of vascular endothelial growth factor small interfering RNA (siRNA) on retinal microvascular endothelial cells under hypoxia condition in vitro].

OBJECTIVE: To explore VEGF siRNA's effect on the immature fetal retinal microvascular endothelial cells in vitro. METHOD: The fresh retinal micrangium was primarily cultured to obtain microvascular endothelial cells. CoCl2 was used to simulate oxygen-deficient conditions. siRNA directed against human VEGF was designed and chemically synthesized. There were 3 groups in our experiment: VEGF siRNA group, hypoxia control group, and negative siRNA control group. The fetal retinal micrangium vascular endothelial cells were transfected by using liposome. The expression levels of VEGF mRNA and protein were evaluated by RT-PCR and Western blotting 24, 48, 72 h after transfection, cell proliferation was evaluated by MTT method. RESULT: The expression levels of VEGF mRNA decreased by 21.05%, 79.67%, and 90.48% 24 h, 48 h, and 72 h after transfection as compared to those in hypoxia control group, the expression level of VEGF protein had decreased by 14.58%, 66.97%, and 81.61% as compared to those in hypoxia control group. The siRNA could decrease cell proliferation under hypoxia too, the multiplication rate after 12, 24, 48, and 72 h decreased by 15.0%, 42.9%, 78.3% and 65.9%. CONCLUSION: VEGF siRNA could down-regulate the expression of VEGF in immature fetal retinal microvascular endothelial cells and suppressed cell proliferation. Application of siRNA to inhibit expression of VEGF may be a hopeful way to prevent and cure ROP.

[Expression and action of vascular endothelial growth factor and its receptor in a rat model of retinopathy of prematurity].

OBJECTIVE: To explore the expression of vascular endothelial growth factor (VEGF) and its receptors (flt-1 and flk-1) in the retina of retinopathy of prematurity (ROP), and its relation to the alteration of retinal blood vessels. METHODS: Eighty-six newborn Sprague-Dawley rats were randomly divided into hyperoxia and air groups, then each group was further divided into 1, 3, 7 and 14 days subgroups. The rats in hyperoxia group inhaled 75% oxygen and ROP model was thus set up. These animals were sacrificed respectively after 1, 3, 7 and 14 days, then the retinal endothelial cells were marked by CD34 to observe the change of retinal blood vessels. The expression of VEGF, flt-1 and flk-1 in the retina was measured by immunohistochemistry. RESULTS: The retinal capillary density index (RCDI) in control group increased as days went on (F = 21.589, P < 0.01, but it was the least on the 7th day in hyperoxia group, after the rats had been returned to air for 7 days, RCDI increased significantly (F = 67.885, P < 0.01); In the control group, the expression of VEGF and flk-1 was the strongest in the retina on the 7th day, the result had significant difference as compared with the 1st and 14th day (P < 0.05). The expression of VEGF and flk-1 on the 7th day in hyperoxia group was weaker than that of control group (P < 0.05). But on the 14th day in hyperoxia group, they were stronger than that of control (P < 0.05). The localization of the expression of flt-1 was changed when blood vessels altered, but there was no significant difference in expression intensity as a whole (P > 0.05). CONCLUSION: When the premature retina was exposed to hyperoxia, the expression of VEGF and flk-1 was reduced, and retinal blood vessels were also decreased; but the expression of VEGF and flk-1 was stronger in retina when premature rats were exposed to relative hypoxia, and the retinal blood vessels also increased significantly. It is concluded that VEGF and flk-1 may play important roles in the development of retinal blood vessels and its change in ROP. However, flt-1 has less effect compared with flk-1.