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Objectives: To investigate the effect of restriction measures during the COVID-19 pandemic on pregnancy duration and outcomes.Methods: We conducted a before and after study with cohort sampling in three maternity hospitals in Melbourne, Australia, including women who were pregnant during the COVID-19 pandemic restriction measures (estimated conception between 1 November 2019 and 29 February 2020) and women who were pregnant before the restrictions (estimated conception between 1 November 2018 and 28 February 2019). The primary outcome was delivery before 34 weeks' gestation or stillbirth. The main secondary outcome was a composite of adverse perinatal outcomes. Pregnancy outcomes were compared between the groups using chi-squared tests and modified Poisson regression models, and pregnancy duration was compared between the groups using and survival analysis.Results: There were 3150 exposed women and 3175 women in the control group. Preterm birth before 34 weeks' gestation or stillbirth occurred in 95 (3.0%) of the pregnancies during restrictions and 130 (4.1%) in the control group (Risk ratio (RR) 0.74, 95% CI 0.57 to 0.96, p = 0.021). The effect was stronger in women with a previous preterm birth (RR 0.42, 95% CI 0.21 to 0.82, p = 0.008). The composite adverse perinatal outcome was less frequent in the exposed group (2.1% versus 2.9%, RR 0.73, 95% CI 0.54 to 0.99, p = 0.042 in all women and 4.5% versus 8.4%, RR 0.54, 95% CI 0.25 to 1.18, p = 0.116 in women with a previous preterm birth).Conclusion: Restrictions to mitigate COVID-19 transmission were associated with reduced rates of preterm birth before 34 weeks. This effect was not associated with increased stillbirth rates and was stronger in women with previous preterm delivery. This article is protected by copyright. All rights reserved. [ABSTRACT FROM AUTHOR]

Objective: Insufflation of the amniotic cavity with carbon dioxide (CO2) is used clinically to improve visibility during complex fetoscopic surgery. Insufflation with heated, humidified CO2 has recently been shown to reduce fetal hypercapnia and acidosis in sheep, compared with use of cold and dry CO2, but the underlying mechanisms are unclear. The aim of this study was to investigate whether differences in placental CO2 and oxygen (O2) exchange during insufflation with heated and humidified vs cold and dry CO2 could explain these findings. Methods: Thirteen fetal lambs at 105 days of gestation (term, 146 days) were exteriorized partially, via a midline laparotomy and hysterotomy, and instrumented with an umbilical artery catheter, an umbilical vein catheter and a common umbilical vein flow probe. Arterial and venous catheters and flow probes were also inserted into the maternal uterine circulation. Six ewes were insufflated with cold, dry CO2 (22°C; 0–5% humidity) and seven with heated, humidified CO2 (40°C; 95–100% humidity) at 15 mmHg for 180 min. Blood‐flow recordings and paired arterial and venous blood gases were sampled from uterine and umbilical vessels. Rates of placental CO2 and O2 exchange were calculated. Results: After 180 min of insufflation, fetal survival was 33% (2/6) using cold, dry CO2 and 71% (5/7) using heated, humidified CO2. By 120 min, fetuses insufflated with heated, humidified CO2 had lower arterial CO2 levels and higher arterial pH compared to those insufflated with cold, dry gas. Insufflation decreased significantly placental gas exchange in both groups, as measured by rates of both (i) fetal CO2 clearance and O2 uptake and (ii) maternal O2 delivery and CO2 uptake from the fetal compartment. Conclusions: Lower arterial CO2 and higher pH levels in fetuses insufflated with heated and humidified, compared to cold and dry, CO2 could not be explained by differences in placental gas exchange. Instead, heated and humidified insufflation appeared to reduce fetal CO2 absorption from the uterus, supporting its use in preference to cold, dry CO2. © 2019 International Society of Ultrasound in Obstetrics and Gynecology [ABSTRACT FROM AUTHOR]

Objectives: Infants with congenital diaphragmatic hernia (CDH) are predisposed to pulmonary hypertension after birth, owing to lung hypoplasia that impairs fetal pulmonary vascular development. Antenatal sildenafil treatment attenuates abnormal pulmonary vascular and alveolar development in rabbit and rodent CDH models, but whether this translates to functional improvements after birth remains unknown. We aimed to evaluate the effect of antenatal sildenafil on neonatal pulmonary hemodynamics and lung function in lambs with diaphragmatic hernia (DH).Methods: DH was surgically induced at approximately 80 days' gestation in 16 lamb fetuses (term in lambs is approximately 147 days). From 105 days' gestation, ewes received either sildenafil (0.21 mg/kg/h intravenously) or saline infusion until delivery (n = 8 fetuses in each group). At approximately 138 days' gestation, all lambs were instrumented and then delivered via Cesarean section. The lambs were ventilated for 120 min with continuous recording of physiological (pulmonary and carotid artery blood flow and pressure; cerebral oxygenation) and ventilatory parameters, and regular assessment of arterial blood gas tensions. Only lambs that survived until delivery and with a confirmed diaphragmatic defect at postmortem examination were included in the analysis; these comprised six DH-sildenafil lambs and six DH-saline control lambs.Results: Lung-to-body-weight ratio (0.016 ± 0.001 vs 0.013 ± 0.001; P = 0.06) and dynamic lung compliance (0.8 ± 0.2 vs 0.7 ± 0.2 mL/cmH2 O; P = 0.72) were similar in DH-sildenafil lambs and controls. Pulmonary vascular resistance decreased following lung aeration to a greater degree in DH-sildenafil lambs, and was 4-fold lower by 120 min after cord clamping than in controls (0.6 ± 0.1 vs 2.2 ± 0.6 mmHg/(mL/min); P = 0.002). Pulmonary arterial pressure was also lower (46 ± 2 vs 59 ± 2 mmHg; P = 0.048) and pulmonary blood flow higher (25 ± 3 vs 8 ± 2 mL/min/kg; P = 0.02) in DH-sildenafil than in DH-saline lambs at 120 min. Throughout the 120-min ventilation period, the partial pressure of arterial carbon dioxide tended to be lower in DH-sildenafil lambs than in controls (63 ± 8 vs 87 ± 8 mmHg; P = 0.057), and there was no significant difference in partial pressure of arterial oxygen between the two groups.Conclusions: Sustained maternal antenatal sildenafil infusion reduced pulmonary arterial pressure and increased pulmonary blood flow in DH lambs for the first 120 min after birth. These findings of improved pulmonary vascular function are consistent with improved pulmonary vascular structure seen in two previous animal models. The data support the rationale for a clinical trial investigating the effect of antenatal sildenafil in reducing the risk of neonatal pulmonary hypertension in infants with CDH. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Objective: Partial amniotic carbon dioxide (CO2 ) insufflation (PACI) is used to improve visualization and facilitate complex fetoscopic surgery. However, there are concerns about fetal hypercapnic acidosis and postoperative fetal membrane inflammation. We assessed whether using heated and humidified, rather than cold and dry, CO2 might reduce the impact of PACI on the fetus and fetal membranes in sheep.Methods: Twelve fetal lambs of 105 days' gestational age (term = 145 days) were exteriorized partially, via a midline laparotomy and hysterotomy, and arterial catheters and flow probes were inserted surgically. The 10 surviving fetuses were returned to the uterus, which was then closed and insufflated with cold, dry (22 °C at 0-5% humidity, n = 5) or heated, humidified (40 °C at 100% humidity, n = 5) CO2 at 15 mmHg for 180 min. Fetal membranes were collected immediately after insufflation for histological analysis. Physiological data and membrane leukocyte counts, suggestive of membrane inflammation, were compared between the two groups.Results: After 180 min of insufflation, fetal survival was 0% in the group which underwent PACI with cold, dry CO2 , and 60% (n = 3) in the group which received heated, humidified gas. While all insufflated fetuses became progressively hypercapnic (PaCO2  > 68 mmHg), this was considerably less pronounced in those in which heated, humidified gas was used: after 120 min of insufflation, compared with those receiving cold, dry gas (n = 3), fetuses undergoing heated, humidified PACI (n = 5) had lower arterial partial pressure of CO2 (mean ± standard error of the mean, 82.7 ± 9.1 mmHg for heated, humidified CO2 vs 170.5 ± 28.5 for cold, dry CO2 during PACI, P < 0.01), lower lactate levels (1.4 ± 0.4 vs 8.5 ± 0.9 mmol/L, P < 0.01) and higher pH (pH, 7.10 ± 0.04 vs 6.75 ± 0.04, P < 0.01). There was also a non-significant trend for fetal carotid artery pressure to be higher following PACI with heated, humidified compared with cold, dry CO2 (30.5 ± 1.3 vs 8.7 ± 5.5 mmHg, P = 0.22). Additionally, the median (interquartile range) number of leukocytes in the chorion was significantly lower in the group undergoing PACI with heated, humidified CO2 compared with the group receiving cold, dry CO2 (0.7 × 10-5 (0.5 × 10-5 ) vs 3.2 × 10-5 (1.8 × 10-5 ) cells per square micron, P = 0.02).Conclusions: PACI with cold, dry CO2 causes hypercapnia, acidosis, hypotension and fetal membrane inflammation in fetal sheep, raising potential concerns for its use in humans. It seems that using heated, humidified CO2 for insufflation partially mitigates these effects and this may be a suitable alternative for reducing the risk of fetal acid-base disturbances during, and fetal membrane inflammation following, complex fetoscopic surgery. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

This review compares and contrasts postharvest food losses (PHLs) and waste in developed countries (especially the USA and the UK) with those in less developed countries (LDCs), especially the case of cereals in sub-Saharan Africa. Reducing food losses offers an important way of increasing food availability without requiring additional production resources, and in LDCs it can contribute to rural development and poverty reduction by improving agribusiness livelihoods. The critical factors governing PHLs and food waste are mostly after the farm gate in developed countries but before the farm gate in LDCs. In the foreseeable future (e.g. up to 2030), the main drivers for reducing PHLs differ: in the developed world, they include consumer education campaigns, carefully targeted taxation and private and public sector partnerships sharing the responsibility for loss reduction. The LDCs’ drivers include more widespread education of farmers in the causes of PHLs; better infrastructure to connect smallholders to markets; more effective value chains that provide sufficient financial incentives at the producer level; opportunities to adopt collective marketing and better technologies supported by access to microcredit; and the public and private sectors sharing the investment costs and risks in market-orientated interventions. [ABSTRACT FROM PUBLISHER]

Objectives: Conventional radiographic imaging of teeth underestimates the presence of caries. The objective of this study was to compare the efficacy of high-resolution cone beam CT (CBCT) images and conventional charge-coupled device (CCD) images for detecting proximal and occlusal caries. Methods: Non-restored, extracted human permanent premolar and molar teeth were mounted and then imaged with a 3DX Accuitomo® and a CCD. We selected 92 occlusal and 100 proximal surfaces for raters to score. Of these, 36 and 25, respectively, had lesions extending into dentin. Using a five-step confidence scale, eight practising dentists evaluated the images for the presence of caries in dentin using both modalities. Actual presence and extent of caries was established with microCT imaging. Results: For proximal surface lesions extending into dentin, the average sensitivity score using 3DX images (0.61) was almost twice that of CCD images (0.33) and the difference was significant. The specificity values for both systems were high and not significantly different from each other. For occlusal surfaces, raters detected significantly more lesions in the enamel or dentin when using the 3DX images than when using CCD images. However, the raters also had significantly lower average specificity scores for the 3DX images compared with the CCD images for lesions at both depths. Conclusions: Practising dentists were able to improve their detection of proximal-surface caries extending into the dentin, but not occlusal caries, using 3DX high-resolution cone beam CT images compared with CCD images. [ABSTRACT FROM AUTHOR]

There is currently an urgent need to develop efficient gene-delivery systems for the lung that are free of inflammatory effects. The LID vector is a synthetic gene delivery system, comprised of lipofectin (L), an integrin-targeting peptide (I) and DNA (D) that has previously been shown to have high transfection efficiency in the lung. We have assessed the effect of alternative methods of complex preparation on structural features of the complex, levels and duration of reporter gene expression and the host response to the LID vector. We have demonstrated that making the complex in water affects the structure of the LID complexes making them smaller and more stable with a more cationic surface charge than complexes prepared in phosphate-buffered saline (PBS). When the LID vector was constituted in water and instilled intratracheally into the lungs of mice there was a 10-fold increase in luciferase activity compared with preparation in PBS. Furthermore, luciferase activity was still evident 1 week following vector instillation. This enhancement may be because of altered complex structure, although effects of the hypotonic vector solution on the lung cannot be excluded. The inflammatory effects of instilling the LID vector in water were minimal, even after three administrations of the LID vector, with only mild alterations in cytokine and broncho-alveolar lavage fluid (BALF) cell profiles. These results demonstrate that the LID vector can generate high, and prolonged, levels of gene expression in the lung from small quantities of DNA and that careful attention to synthetic polyplex structure may be important to optimize efficiency of gene expression in vivo. [ABSTRACT FROM AUTHOR]

Small-scale on-farm storage of maize in Africa is changing, in part due to shifts in the threat from insect pests. A questionnaire survey of 242 households in four closely situated districts in the Volta Region of Ghana, where Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae) arrived ten years ago, was used to show how maize storage practices have changed over the last five years. The survey included asking farmers about changing use of contact insecticides in maize storage in order to guide research and future recommendations. We found high uptake of recommendations developed by a project for reducing Larger Grain Borer damage. Farmers are being pro-active in preventing extensive damage from this pest by replacing the wood of their storage structures, increasing inspection of maize in their stores, and increasing their use of grain protectants. There were differences in post-harvest practices according to district, ethnic group and gender. Grain protectants (traditional methods or commercially available products) were used by 45% of farmers. Cost was the most often cited constraint to the use of recommended commercial products. Farmers reported that their three most important sources of information on maize storage were the agricultural extension services, radio programmes and local networks of friends, family and fellow farmers. [ABSTRACT FROM AUTHOR]