[Folic acid supplementation before and during pregnancy and the risk of preeclampsia].

Objective: To investigate the relationship between folic acid supplementation and the risk of preeclampsia (PE). Methods: A total of 9 048 pregnant women were selected from the First Hospital of Shanxi Medical University in Taiyuan from March 2012 to September 2016. Among them, 882 pregnant women with PE were divided into case group, and 8 166 pregnant women without PE were divided into control group. Information on demographic characteristics, folic acid supplementation, maternal complications, and other factors were collected by face-to-face interviews after child birth in the hospital. Unconditional logistic regression analyses were used to investigate the relationship between folic acid supplementation and the risk of PE and the effects of pre-pregnancy BMI on the relationship of folic acid supplementation with the risk of PE. Results: Compared with nonusers, folic acid supplement users had reduced risk of PE (OR=0.79, 95%CI: 0.64-0.96). Folic acid supplementation before and during pregnancy were negatively related with the risk of PE (OR=0.63, 95%CI: 0.49-0.81). Pregnant women who used folic acid tablets only or used both folic acid tablets and multivitamin containing folic acid had reduced risk of PE (OR=0.81, 95%CI: 0.66-0.99; OR=0.64, 95%CI: 0.49-0.85). No significant relationship was observed in the multivitamin group. Supplemental folic acid doses of <400, 400, and >400 µg/d were related with reduced risk of PE (OR=0.62, 95%CI: 0.42-0.91; OR=0.81, 95%CI: 0.66-0.99; OR=0.68, 95%CI: 0.49-0.94). After stratified by pre-pregnancy BMI, pregnant women who used folic acid supplementation, those with pre-pregnancy BMI<24.0 kg/m(2) had reduced risk of PE (OR=0.75, 95%CI: 0.59-0.96). However, no significant relationship was observed in women with pre-pregnancy BMI≥24.0 kg/m(2). Conclusions: Folic acid supplementation before and during pregnancy were related with reduced risk of PE. Pre-pregnancy BMI might affect the relationship between folic acid supplementation and the risk of PE. Appropriate folic acid supplementation should be recommend for women with different pre-pregnancy BMI.

[Association between periconceptional folic acid supplementation and small for gestational age birth based on pre-pregnancy body mass index].

Objective: To investigate the association between periconceptional folic acid supplementation and small for gestational age (SGA) birth based on maternal pre-pregnancy body mass index (BMI) and provide evidence for the development of comprehensive prevention programs on SGA birth. Methods: Between March, 2012 and September, 2016, a total of 8 523 pregnant women delivering in the First Affiliated Hospital of Shanxi Medical University were surveyed to collect the information about their demographic characteristics, folic acid supplementation before and during pregnancy and about their infants. Among their infants, 1 066 were small for gestational age (case group), 7 457 were appropriate for gestational age (AGA) (control group). Unconditional logistic regression model was used to evaluate the association between periconceptional folic acid supplementation and SGA birth in the context of different pre-pregnancy BMI. Results: The overall incidence of SGA birth was 12.51% (1 066/8 523). After adjusting the confounding factors, pre-pregnancy BMI<18.5 kg/m(2) was a risk factor for SGA birth (OR=1.22, 95%CI: 1.01-1.47), pre-pregnancy BMI≥24.0 kg/m(2) was associated with a reduced risk of SGA birth (OR=0.81, 95%CI:0.68-0.97). After adjusting confounding factors, periconceptional folic acid supplementation was a protective factor for SGA birth (OR=0.82, 95%CI: 0.68-0.98). After stratified by pre-pregnancy BMI, periconceptional folic acid supplementation was associated with the reduced risk of SGA birth in overweight group (24.0 kg/m(2)≤BMI<28.0 kg/m(2)) with OR of 0.55 (95%CI: 0.36-0.85). No significant association was observed in other groups. When examined by folic acid supplement type, periconceptional single folic acid supplementation (400 µg per tablet) was a protective factor for SGA birth (OR=0.82, 95%CI: 0.69-0.99). After stratified by pre-pregnancy BMI, periconceptional single folic acid supplementation (400 µg per tablet) was associated with the reduced risk of SGA birth in overweight groups (OR=0.56, 95%CI: 0.36-0.86). No association was observed between periconceptional folic acid containing multivitamin supplementation and SGA birth. Conclusions: Periconceptional folic acid supplementation (400 µg) was associated with reduced risk of SGA birth in women with pre-pregnancy BMI≥24.0 kg/m(2) and<28.0 kg/m(2). No association between folic acid supplementation and SGA was observed in other groups. This study suggests that pre-pregnancy BMI might modify the influence of folic acid supplementation on the risk of SGA birth.

Cytoarchitecture and sound activated responses in the auditory cortex of the big brown bat, Eptesicus fuscus.

Under free field and closed-system stimulation conditions, we studied the frequency threshold curves, auditory spatial sensitivity and binaurality of neurons in the primary auditory cortex (AC) of the big brown bat, Eptesicus fuscus. All 298 recorded AC neurons discharged phasically. They were recorded at depths less than 1,000 microns with response latencies of 7-25 ms, best frequencies (BFs) of 28-97 kHz and minimum thresholds (MTs) of 8-90 dB SPL. They received excitatory inputs from the contralateral ear and either excitatory (EE) or inhibitory (EI) inputs from the ipsilateral ear. These cortical neurons were tonotopically organized along the anteroposterior axis of the AC. High best frequency neurons were located anteriorly and low best frequency neurons posteriorly. They were most sensitive to sounds delivered from a restricted region of the contralateral frontal auditory space (0 degree-50 degrees in azimuth and 2 degrees up, 15 degrees down in elevation). Frontal auditory space representation appears to be systematically arranged according to the tonotopic axis such that the lateral space is represented posteriorly and the middle space anteriorly. Cortical neurons sequentially isolated from an orthogonally penetrated electrode had similar frequency threshold curves, BFs, MTs, points of maximal auditory spatial sensitivity and binaurality. The EE and EI columns are organized concentrically such that the small number of centrally located EE columns were surrounded by an overwhelming number of EI columns. Using Nissl and Golgi stains as well as c-fos immunocytochemistry, we studied the cytoarchitecture, cell types and sound elicited Fos-like immunoreactivity in the primary AC of this bat species. The primary AC of this bat species can be described into molecular (137 microns), external granular (55 microns), external pyramidal (95 microns), internal granular (102 microns), internal pyramidal (191 microns) and multiform (120 microns) layers. The main type of cells distributed among these six layers are the small, medium and large pyramidal cells. Others include the stellate, horizontal, granular, fusiform, basket, and Martinotii cells. When stimulated with 30 kHz and 79 dB SPL sounds under natural conditions, bilaterally and symmetrically distributed Fos-like immunoreactive neurons were observed in about 20% of neurons in each AC. When stimulated under monaurally plugged conditions, 39-48% more of Fos-like immunoreactive neurons were observed in the ipsilateral AC. This finding supports the fact that the primary AC receives auditory inputs mainly from the contralateral ear.

Morphology and physiology of auditory interneurons of the bushcricket Gampsocleis gratiosa.

Seven types of auditory interneurons were characterized from the prothoracic ganglion of the bushcricket. They are sensitive in the range of 7-18 kHz and fire with distinct discharge patterns. They encode sound intensity and temporal parameters in various way. They show significant directional sensitivity, dependent on sound frequency. The acoustic tracheal system can partly account for the directional hearing of the bushcricket.