Increased Impact of Air Pollution on Lung Function in Preterm versus Term Infants: The BILD Study.

Rationale: Infants born prematurely have impaired capacity to deal with oxidative stress shortly after birth. Objectives: We hypothesize that the relative impact of exposure to air pollution on lung function is higher in preterm than in term infants. Methods: In the prospective BILD (Basel-Bern Infant Lung Development) birth cohort of 254 preterm and 517 term infants, we investigated associations of particulate matter ⩽10 µm in aerodynamic diameter (PM10) and nitrogen dioxide with lung function at 44 weeks' postconceptional age and exhaled markers of inflammation and oxidative stress response (fractional exhaled nitric oxide [FeNO]) in an explorative hypothesis-driven study design. Multilevel mixed-effects models were used and adjusted for known confounders. Measurements and Main Results: Significant associations of PM10 during the second trimester of pregnancy with lung function and FeNO were found in term and preterm infants. Importantly, we observed stronger positive associations in preterm infants (born 32-36 wk), with an increase of 184.9 (95% confidence interval [CI], 79.1-290.7) ml/min [Formula: see text]e per 10-µg/m3 increase in PM10, than in term infants (75.3; 95% CI, 19.7-130.8 ml/min) (pprematurity × PM10 interaction = 0.04, after multiple comparison adjustment padj = 0.09). Associations of PM10 and FeNO differed between moderate to late preterm (3.4; 95% CI, -0.1 to 6.8 ppb) and term (-0.3; 95% CI, -1.5 to 0.9 ppb) infants, and the interaction with prematurity was significant (pprematurity × PM10 interaction = 0.006, padj = 0.036). Conclusions: Preterm infants showed significantly higher susceptibility even to low to moderate prenatal air pollution exposure than term infants, leading to increased impairment of postnatal lung function. FeNO results further elucidate differences in inflammatory/oxidative stress response when comparing preterm infants with term infants.

Risk factors for developmental defects of enamel in children from southeastern Brazil.

INTRODUCTION: Developmental Defects of Enamel (DDEs) comprise qualitative and/or quantitative changes to the enamel during amelogenesis. The aetiology of DDE remains inconclusive. AIM: To determine the association of pre, peri, and postnatal factors with the presence of DDE. DESIGN: Cross-sectional study with 353 children (8 to 11 years-old) in a Brazilian town. METHODS: One calibrated dentist assessed DDE using the Developmental Defects of Enamel Index and a questionnaire collected medical and sociodemographic data. MAIN OUTCOMES: Children with at least one type of DDE were categorized into the DDE group. Subtypes of DDE were also recorded. RESULTS: 63.1% of children had at least one type of DDE. Diffuse opacity was present in 36.7%, demarcated opacity in 14.8%, and hypoplasia in 5.83% of the children. In multivariate analysis, demarcated opacities and hypoplasia were associated with birth weight ⟨ 2500g (OR = 4.82; 95% CI 1.23-1.95). CONCLUSION: Low birth weight predicted DDE.

Normal Hearing Function in Children Prenatally Exposed to Zika Virus

Abstract Introduction The association between prenatal Zika virus infection and hearing alterations in offspring has been the object of some studies, although few have assessed children without microcephaly. However, a current trend to include prenatal Zika virus exposure in the group of risk indicators for hearing loss is noted. Objective To present a series of 27 children prenatally exposed to the Zika virus submitted to multiple hearing assessments over time. Methods A cohort of children born to symptomatic mothers with laboratorial Zika virus infection confirmation during pregnancy was submitted to an otoacoustic emission test, auditory brainstem response test (automated, neurodiagnostic and frequency-specific), audiometry, and imitanciometry over a period of 36 months since birth. The hearing assessment was performed independently of the presence of microcephaly or other apparent signs of congenital Zika syndrome. Results The hearing tests presented predominantly normal results. Some children had signs of middle ear pathology. The only microcephalic child had normal electrophysiological tests, as well as preserved audiometric thresholds, but presented altered motor responses to sound. Conclusion Prenatal exposure to Zika virus does not always determine hearing impairment. This risk seems to be more associated to the severity of the central nervous system damage. Hearing screening and follow-ups of the affected children are important, as well as further research in this area.

Normal Hearing Function in Children Prenatally Exposed to Zika Virus.

Introduction The association between prenatal Zika virus infection and hearing alterations in offspring has been the object of some studies, although few have assessed children without microcephaly. However, a current trend to include prenatal Zika virus exposure in the group of risk indicators for hearing loss is noted. Objective To present a series of 27 children prenatally exposed to the Zika virus submitted to multiple hearing assessments over time. Methods A cohort of children born to symptomatic mothers with laboratorial Zika virus infection confirmation during pregnancy was submitted to an otoacoustic emission test, auditory brainstem response test (automated, neurodiagnostic and frequency-specific), audiometry, and imitanciometry over a period of 36 months since birth. The hearing assessment was performed independently of the presence of microcephaly or other apparent signs of congenital Zika syndrome. Results The hearing tests presented predominantly normal results. Some children had signs of middle ear pathology. The only microcephalic child had normal electrophysiological tests, as well as preserved audiometric thresholds, but presented altered motor responses to sound. Conclusion Prenatal exposure to Zika virus does not always determine hearing impairment. This risk seems to be more associated to the severity of the central nervous system damage. Hearing screening and follow-ups of the affected children are important, as well as further research in this area.

Exposure to Electromagnetic Field during Gestation Adversely Affects the Electrophysiological Properties of Purkinje Cells in Rat Offspring.

BACKGROUND: Prenatal adverse effects of radiofrequency electromagnetic fields (RF-EMF) exposure on nervous system are an issue of major concern. OBJECTIVE: Thus, in this study we evaluated the membrane current flow properties of Purkinje neurons after maternal exposure to 900 MHz pulsed RF-EMF. MATERIAL AND METHODS: In this experimental study, during all days of pregnancy, rats in the EMF-exposed group were exposed to 900 MHz pulsed-EMF radiation for 6 h per day. The effects of RF-EMF exposure on the electrophysiological properties of the Purkinje cerebellum neurons from male pups were evaluated by whole-cell patch clamp recordings in current and voltage clamp modes. In voltage-clamp experiments, the holding potential was -60mV, and a depolarizing voltage step (1000 ms duration) was applied from -60 to +50 mV in 10 mV increments at 2s intervals. RESULTS: The exposure group demonstrated reduced spontaneous firing associated with upward and rightward shift in I/V curve compared to the control rats. Moreover, the peak amplitude of the current for the exposure pups also revealed a significant decrement. The reversal potential was +40 mV and +20 mV for the control and RF-EMF groups, respectively and showed significant differences between the two groups. CONCLUSION: The decrease in ion's conductance could be attributed to the observed decrease in the voltage onset of the inward current, peak amplitude and voltage shift.

Does prenatal restraint stress change the craniofacial growth pattern of rat offspring?

A major and frequently encountered condition underlying the long-term programming effects of the intrauterine environment is exposure to stress. Gestational stress is an environmental factor that induces physical and behavioral alterations in offspring. Seventy female virgin Wistar rats were mated with one male rat for a maximum of four times, after which 52 pregnant rats were divided into two groups. In the experimental group the rats were exposed to restraint stress during pregnancy, whereas the control group did not receive the stress protocol. One male litter was randomly chosen from the offspring of each rat with 8-13 pups. A total of 40 male rat offspring were available for analysis. Thirty-one linear and angular measurements were analyzed in both study groups to investigate whether prenatal restraint stress changes the craniofacial growth pattern of rat offspring. In the prenatally stressed group, anterior cranial base length and viscerocranium measures were significantly increased compared with the control group, whereas cranial width, mandibular dimensions, and posterior cranial height and length remained unchanged. Furthermore, the prenatally stressed group showed backward rotation of the midface and decreased flattening of the cranial vault. It was concluded that prenatal chronic stress can induce alterations in the craniofacial growth pattern by promoting endochondral growth in the cranial base and nasal septum.