Amniotic fluid water dynamics

Intra-Amniotic Sildenafil and Rosiglitazone Late in Gestation Ameliorate the Pulmonary Hypertension Phenotype in Congenital Diaphragmatic Hernia

BACKGROUND

Pulmonary hypertension remains difficult to manage in congenital diaphragmatic hernia (CDH). Prenatal therapy may ameliorate postnatal pulmonary hypertension. We hypothesized that intra-amniotic (IA) injection of either sildenafil, a phosphodiesterase 5 inhibitor, or rosiglitazone, a PPAR-γ agonist, or both late in gestation would decrease the detrimental pulmonary vascular remodeling seen in CDH and improve peripheral pulmonary blood flow.

METHODS

Pregnant rats were gavaged with nitrogen on embryonic day (E) 9.5 to induce fetal CDH. Sildenafil and/or rosiglitazone were administered to each fetus via an intra-amniotic injection after laparotomy on the pregnant dam at E19.5, and fetuses delivered at E21.5. Efficacy measures were gross necropsy, histology, peripheral blood flow assessment using intra-cardiac injection of a vascular tracer after delivery, and protein expression analysis.

RESULTS

Intra-amniotic injections did not affect fetal survival, the incidence of CDH, or lung weight-to-body weight ratio in CDH fetuses. IA sildenafil injection decreased pulmonary vascular muscularization, and rosiglitazone produced an increase in peripheral pulmonary blood flow distribution. The combination of sildenafil and rosiglitazone decreased pulmonary artery smooth muscle cell proliferation. These intra-amniotic treatments did not show any negative effects in either CDH fetuses or control fetuses.

CONCLUSION

IA injection of sildenafil and rosiglitazone late in gestation ameliorates the pulmonary hypertensive phenotype of CDH and may have utility in clinical translation.

LEVEL OF EVIDENCE

Not applicable.

Immersed in a reservoir of potential: amniotic fluid-derived extracellular vesicles

This review aims to encapsulate the current knowledge in extracellular vesicles extracted from amniotic fluid and amniotic fluid derived stem/stromal cells. Amniotic fluid (AF) bathes the developing fetus, providing nutrients and protection from biological and mechanical dangers. In addition to containing a myriad of proteins, immunoglobulins and growth factors, AF is a rich source of extracellular vesicles (EVs). These vesicles originate from cells in the fetoplacental unit. They are biological messengers carrying an active cargo enveloped within the lipid bilayer. EVs in reproduction are known to play key roles in all stages of pregnancy, starting from fertilisation through to parturition. The intriguing biology of AF-derived EVs (AF-EVs) in pregnancy and their untapped potential as biomarkers is currently gaining attention. EV studies in numerous animal and human disease models have raised expectations of their utility as therapeutics. Amniotic fluid stem cell and mesenchymal stromal cell-derived EVs (AFSC-EVs) provide an established supply of laboratory-made EVs. This cell-free mode of therapy is popular as an alternative to stem cell therapy, revealing similar, if not better therapeutic outcomes. Research has demonstrated the successful application of AF-EVs and AFSC-EVs in therapy, harnessing their anti-inflammatory, angiogenic and regenerative properties. This review provides an overview of such studies and discusses concerns in this emerging field of research.

Is salivary uric acid, a putative biomarker of pre-eclampsia, of maternal, placental, or fetal origin?

OBJECTIVES

Increased salivary uric acid (sUA) represents a potential biomarker predictive of pre-eclampsia (PE), but its origin is unclear. The study explores whether sUA levels reflect maternal or feto-placental physiological stress and whether sUA levels in these cases correlate with amniotic fluid (fetal origin), maternal blood (maternal origin), or cord blood (fetal vs placental origin).

STUDY DESIGN

Pregnant women (n = 39) undergoing amniotomy or caesarean section after 34 gestational weeks were designated into three groups of either maternal, feto-placental, or no signs of physiological stress: women (n = 15) in the established first phase of active labour and without any signs of fetal growth restriction (FGR) or PE were assigned to the maternal stress group, women (n = 6) with an ultrasound-based diagnosis of FGR, with or without PE, were assigned to the feto-placental stress group, and women (n = 18) not yet in active labour and without any signs of FGR or PE, were assigned to the control group. Uric acid levels in corresponding samples of amniotic fluid, saliva, maternal blood, and cord blood were compared between groups and between body compartments within each group.

RESULTS

The feto-placental stress group showed increased UA levels in saliva (median, interquartile range [IQR]: 0.47 [0.38] mmol/L, P = 0.023) and maternal blood (0.42 [0.13] mmol/L, P = 0.032), but no differences in amniotic fluid or cord blood compared with the other groups. Within the control and maternal stress group, sUA levels were lower compared with maternal blood (0.20 [0.08] vs 0.25 [0.08] mmol/L, Pcontrol = 0.018; 0.20 [0.06] vs 0.26 [0.08] mmol/L, Pmaternal = 0.001) and highest in amniotic fluid (control group (0.49 [0.18] mmol/L): Pmaternal,blood = 0.001, Pumbilical,artery = <0.001, Pumbilical,vein = <0.001, Psaliva = <0.001) (maternal stress group (0.56 [0.23] mmol/L): Pmaternal,blood = 0.021, Pumbilical,artery = 0.006, Pumbilical,vein = 0.004, Psaliva = 0.003). Levels did not differ between compartments in the feto-placental stress group.

CONCLUSIONS

Salivary and maternal blood UA levels were increased in the feto-placental stress group with salivary levels increasing more than blood levels compared with the maternal stress and control groups, whilst UA in amniotic fluid were not different between the groups, suggesting a placental origin and potential use of sUA as a biomarker of placental dysfunction, including FGR and severe PE.

Single-cell guided prenatal derivation of primary fetal epithelial organoids from human amniotic and tracheal fluids

Isolation of tissue-specific fetal stem cells and derivation of primary organoids is limited to samples obtained from termination of pregnancies, hampering prenatal investigation of fetal development and congenital diseases. Therefore, new patient-specific in vitro models are needed. To this aim, isolation and expansion of fetal stem cells during pregnancy, without the need for tissue samples or reprogramming, would be advantageous. Amniotic fluid (AF) is a source of cells from multiple developing organs. Using single-cell analysis, we characterized the cellular identities present in human AF. We identified and isolated viable epithelial stem/progenitor cells of fetal gastrointestinal, renal and pulmonary origin. Upon culture, these cells formed clonal epithelial organoids, manifesting small intestine, kidney tubule and lung identity. AF organoids exhibit transcriptomic, protein expression and functional features of their tissue of origin. With relevance for prenatal disease modeling, we derived lung organoids from AF and tracheal fluid cells of congenital diaphragmatic hernia fetuses, recapitulating some features of the disease. AF organoids are derived in a timeline compatible with prenatal intervention, potentially allowing investigation of therapeutic tools and regenerative medicine strategies personalized to the fetus at clinically relevant developmental stages.

Functional MRI assessment of the lungs in fetuses that deliver very Preterm: An MRI pilot study

OBJECTIVES

To compare mean pulmonary T2* values and pulmonary volumes in fetuses that subsequently spontaneously delivered before 32 weeks with a control cohort with comparable gestational ages and to assess the value of mean pulmonary T2* as a predictor of preterm birth < 32 weeks' gestation.

METHODS

MRI datasets scanned at similar gestational ages were selected from fetuses who spontaneously delivered < 32 weeks of gestation and a control group who subsequently delivered at term with no complications. All women underwent a fetal MRI on a 3 T MRI imaging system. Sequences included T2-weighted single shot fast spin echo and T2* sequences, using gradient echo single shot echo planar sequencing of the fetal thorax. Motion correction was performed using slice-to-volume reconstruction and T2* maps generated using in-house pipelines. Lungs were manually segmented and volumes and mean T2* values calculated for both lungs combined and left and right lung separately. Linear regression was used to compare values between the preterm and control cohorts accounting for the effects of gestation. Receiver operating curves were generated for mean T2* values and pulmonary volume as predictors of preterm birth < 32 weeks' gestation.

RESULTS

Datasets from twenty-eight preterm and 74 control fetuses were suitable for analysis. MRI images were taken at similar fetal gestational ages (preterm cohort (mean ± SD) 24.9 ± 3.3 and control cohort (mean ± SD) 26.5 ± 3.0). Mean gestational age at delivery was 26.4 ± 3.3 for the preterm group and 39.9 ± 1.3 for the control group. Mean pulmonary T2* values remained constant with increasing gestational age while pulmonary volumes increased. Both T2* and pulmonary volumes were lower in the preterm group than in the control group for all parameters (both combined, left, and right lung (p < 0.001 in all cases). Adjusted for gestational age, pulmonary volumes and mean T2* values were good predictors of premature delivery in fetuses < 32 weeks (area under the curve of 0.828 and 0.754 respectively).

CONCLUSION

These findings indicate that mean pulmonary T2* values and volumes were lower in fetuses that subsequently delivered very preterm. This may suggest potentially altered oxygenation and indicate that pulmonary morbidity associated with prematurity has an antenatal antecedent. Future work should explore these results correlating antenatal findings with long term pulmonary outcomes.

Water Intake and Hydration Status among Pregnant Women in the Second Trimester in China: A Three-Day Metabolic Trial

Adequate water intake and optimal hydration status during pregnancy are crucial for maternal and infant health. However, research on water intake by pregnant women in China is very limited. This study mainly aimed to observe the daily total water intake (TWI) of pregnant women and its different sources and to investigate the relationship between their water intake and hydration biomarkers. From October to November 2020, a convenience sample of pregnant women in the second trimester (n = 21) was recruited. Under conditions close to daily life, they undertook a 3-day metabolic trial. Each participant was provided with sufficient bottled water, and the weight of what they drank each time was measured. The intake of other beverages and foods was measured using a combination of weighing and duplicate portion method. Fasting venous blood and 24 h urine samples were collected and analyzed for the hydration biomarkers, including the serum/urine osmolality, urine pH, urine specific gravity, and the concentrations of major electrolytes in urine and serum. The results showed that the mean daily TWI was 3151 mL, of which water from beverages and foods accounted for 60.1% and 39.9%, respectively. The mean total fluid intake (TFI) was 1970 mL, with plain water being the primary contributor (68.7%, r = 0.896). Among the participants, 66.7% (n = 14, Group 1) met the TWI recommendation set by the Chinese Nutrition Society. Further analysis revealed that the TFI, water from beverages and foods, plain water, and milk and milk derivatives (MMDs) were significantly higher in Group 1 than those who did not reach the adequate intake value (Group 2) (p < 0.05). The results of hydration biomarkers showed that the mean 24 h urine volume in Group 1 was significantly higher than that in Group 2 (p < 0.05), while the 24 h urine osmolality, sodium, magnesium, phosphorus, chloride, and creatinine concentrations in Group 1 were significantly lower than those in Group 2 (p < 0.05). However, no significant differences were observed in serum biomarkers. Partial correlation analysis showed that TWI was moderately positively correlated with 24 h urine volume (r = 0.675) and negatively correlated with urine osmolality, sodium, potassium, magnesium, calcium, phosphorus, and chloride concentrations (r = from-0.505 to -0.769), but it was not significantly correlated with serum biomarkers. Therefore, under free-living conditions, increasing the daily intake of plain water and MMDs is beneficial for pregnant women to maintain optimal hydration. The hydration biomarkers in urine are more accurate indicators of water intake and exhibit greater sensitivity compared to serum biomarkers. These findings provide a scientific basis for establishing appropriate water intake and hydration status for pregnant women in China.

The Amount of Fluid Intake among Pregnant Women in China Increases with Pregnancy Progression: A Prospective Cohort Study

Fluid intake and hydration status during pregnancy may have influences on maternal and infant health. However, few studies have recorded and analyzed total fluid intake (TFI) levels during the whole pregnancy. This study mainly aimed to investigate the TFI levels of pregnant women in three trimesters, and further to assess their hydration status. The relationships of TFI and hydration status were also analyzed. A convenience sampling method was used to recruit pregnant women from the Haikou Maternity and Child Health Hospital in China in this prospective cohort study. A 7-day 24 h fluid intake questionnaire was used for recording the fluid intake of the participants in their three trimesters. Fasting blood samples and first morning urine samples were also collected and tested. Hydration status was evaluated using urine osmolality. Finally, 142 pregnant women completed the study. The median TFIs in the first, second, and third trimesters were 1336, 1477, and 1584 mL, respectively. The TFI levels increased with pregnancy progression (χ2 = 134.155, p < 0.05). Out of 142 participants, 100.0%, 97.2%, and 85.2% of participants did not reach the recommendation amount for an adequate TFI among Chinese pregnant women in the three trimesters, respectively (χ2 = 29.840, p < 0.05). Plain water was the main source of fluid intake, accounting for 92.0%, 94.2%, and 93.4% of TFI, respectively. The median values of dairy product intake were 61, 57, and 59 mL in the three trimesters. The frequency of participants without an optimal hydration status in the three trimesters was 71.8%, 76.1%, and 83.1%, respectively (χ2 = 29.909, p < 0.05). The participants of each trimester were divided into four groups according to quartiles of TFI, including participants with a lower fluid intake (LFI1 and LFI2) and higher fluid intake (HFI1 and HFI2). As the TFI values increased from the LFI1 group to the HFI2 group, the urine osmolality decreased (all p < 0.05). Moderate-intensity negative correlations were found between urine osmolality, hydration status, and TFI (all p < 0.05). It is suggested that fluid intake strategies should be promoted and health education should be conducted to improve the hydration status of pregnant women.

Amniotic fluid content in children with kidney and urinary tract anomalies determines pre- and postnatal development

BACKGROUND

Renal oligohydramnios (ROH) describes an abnormally low volume of amniotic fluid (AF) during pregnancy. ROH is mostly caused by congenital fetal kidney anomalies. The ROH diagnosis frequently implies an increased risk of peri- and postnatal fetal mortality and morbidity. The present study aimed to evaluate the impact of ROH on pre-and postnatal development in children with congenital kidney anomalies.

METHODS

This retrospective study included 168 fetuses with anomalies in the kidney and urinary tract. Based on the amount of AF measured by ultrasound, patients were divided into three groups: normal amniotic fluid (NAF), amniotic fluid in the lower normal range (LAF), and ROH. These groups were compared with respect to prenatal sonographic parameters, perinatal outcomes, and postnatal outcomes.

RESULTS

Among the 168 patients with congenital kidney anomalies, 26 (15%) had ROH, 132 (79%) had NAF, and 10 (6%) had LAF. Of the 26 families affected by ROH, 14 (54%) decided to terminate pregnancy. Of 10 live-born children in the ROH group, 6 (60%) survived the observation time; of these, 5/6 presented with chronic kidney disease, stages I-III, at their last examination. The main differences in postnatal development between the ROH group and the NAF and LAF groups were: restricted height and weight gain, respiratory issues, complicated feeding, and the presence of extrarenal malformations.

CONCLUSIONS

ROH is not a mandatory indicator of severe postnatal kidney function impairment. However, children with ROH have complicated peri-and postnatal periods, due to the presence of concomitant malformations, which must be considered in prenatal care. A higher resolution version of the Graphical abstract is available as Supplementary information.

Intra-amniotic sildenafil treatment improves lung blood flow and pulmonary hypertension in congenital diaphragmatic hernia rats

Pulmonary hypertension associated with congenital diaphragmatic hernia (CDH) is a critical factor in determining prognosis. We propose that intra-amniotic sildenafil administration is an effective prenatal therapy for CDH-induced pulmonary hypertension. To assess the efficacy of this treatment, we administered sildenafil to nitrofen-induced congenital diaphragmatic hernia fetuses and control fetuses via an intra-amniotic injection after a laparotomy on the pregnant dam at either E13.5 or E15.5. Intra-amniotic sildenafil treatment attenuated peripheral vascular muscularization, enhanced pulmonary blood flow, and increased the ratio of pulmonary artery size to aortic size in congenital diaphragmatic hernia fetuses after both E13.5 and E15.5 treatments. E13.5-treated congenital diaphragmatic hernia fetuses showed a higher and more prolonged expression of cyclic guanosine monophosphate (cGMP)-dependent protein kinase and more production of vascular endothelial growth factor, resulting in a significant improvement in lung architecture. The E13.5-treated congenital diaphragmatic hernia fetuses also had an increase in lung weight-to-body weight ratio and an improved fetal survival. Intra-amniotic sildenafil treatment did not show any detectable negative effects in control fetuses. Intra-amniotic sildenafil treatment for rats attenuates CDH-induced pulmonary hypertension and enhanced peripheral pulmonary blood flow. Moreover, early intervention may be preferable to better accelerate lung development and improve prognosis. Direct sildenafil administration via an intra-amniotic injection may be a promising option in congenital diaphragmatic hernia prenatal therapy.

A Randomized Trial of Inpatient and Home-Based Maternal Oral Hydration Therapy in Isolated Oligohydramnios and Its Effect on Amniotic Fluid Index and Perinatal Outcome

Background Isolated oligohydramnios, without any known fetal/maternal abnormality, may be associated with insufficient oral intake (such as water, glucose, and rehydration therapy). Therefore, the present study was conducted to assess the improvement following maternal hydration. Method A total of 50 cases of isolated oligohydramnios (other high-risk pregnancy conditions not present) were included in the study (25 in each group). Patients were encouraged for an additional 2 liters of oral rehydration solution intake daily along with regular diet. The fluid intake was unsupervised in the home group and supervised in the hospital group. Serial amniotic fluid index (AFI) measurements and fetal monitoring were performed. Birth weight and APGAR scores were recorded, and data were analyzed. Results The two groups were comparable in terms of demographics and baseline laboratory findings. AFI significantly improved in the hospital group compared to the home group (p-value: <0.001). Birth weight, placental weight, and APGAR scores were also significantly better in the hospital group than in the home group. Conclusion Maternal oral hydration therapy improves the amniotic fluid volume and subsequently improves the perinatal outcome. Due to poor compliance with home-based treatment, institution of supervised hydration therapy is recommended.

AFNet Algorithm for Automatic Amniotic Fluid Segmentation from Fetal MRI

Amniotic Fluid Volume (AFV) is a crucial fetal biomarker when diagnosing specific fetal abnormalities. This study proposes a novel Convolutional Neural Network (CNN) model, AFNet, for segmenting amniotic fluid (AF) to facilitate clinical AFV evaluation. AFNet was trained and tested on a manually segmented and radiologist-validated AF dataset. AFNet outperforms ResUNet++ by using efficient feature mapping in the attention block and transposing convolutions in the decoder. Our experimental results show that AFNet achieved a mean Intersection over Union (mIoU) of 93.38% on our dataset, thereby outperforming other state-of-the-art models. While AFNet achieves performance scores similar to those of the UNet++ model, it does so while utilizing merely less than half the number of parameters. By creating a detailed AF dataset with an improved CNN architecture, we enable the quantification of AFV in clinical practice, which can aid in diagnosing AF disorders during gestation.

Tanshinone IIA changed the amniotic fluid volume and regulated expression of AQP1 and AQP3 in amniotic epithelium cells: a promising drug treating abnormal amniotic fluid volume

BACKGROUND

Many studies have confirmed the association of aquaporins (AQPs) with abnormal amniotic fluid volume (AFV). In our previous experiments, we found that Tanshinone IIA was able to regulate the expression of AQP1 and AQP3. However, the exact mechanism by which Tanshinone IIA regulates AQPs protein expression and its effect on AFV remains unclear. The purpose of this study was to investigate the effects of Tanshinone IIA on AFV and the possible molecular mechanism of regulation of AQP1 and AQP3.

METHODS

The expression of AQPs protein in the amniotic membranes was compared between pregnant women with normal pregnancy and those with isolated oligohydramnios. The AQP1 knockout (AQP1-KO) mice and wild-type (WT) mice were treated with saline or Tanshinone IIA (10 mg/kg) at 13.5GD and 16.5GD. Human amniotic epithelium cells (hAECs) from pregnant women with normal AFV and isolated oligohydramnios were incubated with 35 μmmol/L Tanshinone IIA or 25 mmol/L LiCl [inhibitor of glycogen synthetic kinase 3β (GSK-3β)]. The protein expressions of AQPs, GSK-3β, phospho-GSK-3β (Ser9) in fetal membranes of mice and human amniotic epithelium cells were detected by western blotting.

RESULTS

The expression of AQP1 protein in the amniotic membrane of isolated oligohydramnios was increased compared with normal pregnancy. The AFV in AQP1-KO mice is higher than that in WT mice. In wild-type mice, AFV in Tanshinone IIA group was significantly higher than that in control group, and AQP1 protein expression was significantly lower than that in control group, but in AQP1 knockout mice, Tanshinone IIA reduced amniotic fluid volume and AQP3 protein expression at 16.5GD. Tanshinone IIA reduced AQP1, AQP3 and p-GSK-3β (Ser9) protein expression in normal hAECs, and this effect was inhibited by LiCl. In hAECs with oligohydramnios, the down-regulation of AQP1 and up-regulation of AQP3 by Tanshinone IIA was independent of GSK-3β signaling pathway.

CONCLUSIONS

Tanshinone IIA may increase AFV in normal pregnancy by downregulating AQP1 protein expression in the fetal membranes, which may be associated with p-GSK-3β signaling pathway. But a larger AFV in AQP1-KO mice was significantly attenuated by Tanshinone IIA, which may be related to AQP3. Tanshinone IIA is a promising drug for the treatment of amniotic fluid abnormality.

Intra-amniotic sildenafil administration in rabbits: Safety, pharmacokinetics, organ distribution and histologic evaluation

BACKGROUND

The effectiveness of sildenafil in the management of pulmonary hypertension in congenital diaphragmatic hernia (CDH) has been reported but has not been systematically evaluated. Our studies have also demonstrated that intra-amniotic (IA) sildenafil administration improves pulmonary hypertension in CDH.

METHODS

We evaluated the pharmacokinetics of sildenafil after IA administration in pregnant rabbits. Following maternal laparotomy, fetuses received IA injection of 0.8 mg of sildenafil. Maternal blood, amniotic fluid, and fetal tissues were collected at various time points. The concentrations of sildenafil and its major metabolite in samples were analyzed by liquid chromatography-mass spectrometry. To assess organ toxicity, 7 days after IA sildenafil administration, fetal organs were examined histologically.

RESULTS

After IA dosing, sildenafil was absorbed quickly with an absorption half-life of 0.03-0.07 h into the fetal organs. All the organs showed a maximum concentration within 1 h and the disposition half-life ranged from 0.56 to 0.73 h. Most of the sildenafil was eliminated from both mothers and fetuses within 24 h after a single dose. There was no histological evidence of organ toxicity in the fetuses after a single dose of IA administration of sildenafil.

CONCLUSION

IA sildenafil is rapidly absorbed into the fetus, distributes into the mother and is eliminated by the mother without accumulation or fetal organ toxicity. This study confirms the feasibility and the safety of IA administration of sildenafil and enables future applications in the treatment of CDH fetuses.

A Study of the Fluid Intake, Hydration Status, and Health Effects among Pregnant Women in Their Second Trimester in China: A Cross-Sectional Study

The fluid intake and hydration status during pregnancy may influence the health outcomes of both the mother and the fetus. However, there are few studies related to this. The aim of the present study was to investigate fluid intake behaviors among pregnant women in their second trimester, to evaluate their hydration status and pregnancy complications, and to further explore the association of fluid intake and the amniotic fluid index (AFI). Participants’ total fluid intake (TFI) levels were determined using a 7-day 24 h fluid intake questionnaire. The levels of water intake from food were not recorded or measured. Morning urine samples were collected, and both urine osmolality levels and urine specific gravity (USG) were tested to evaluate their hydration status. Fasting blood samples were also collected and measured for osmolality and complete blood count (CBC). A total of 324 participants completed the study. They were divided into four groups based on quartiles of TFI, including participants with lower (LFI1 and LFI2) and higher (HFI1 and HFI2) fluid intake levels. The median TFI was 1485 mL, and the median values of the four groups with different TFI levels were 1348, 1449, 1530, and 1609 mL, respectively. Only 3.4% of the participants attained the recommended value following an adequate water intake (1.7 L) level for pregnant women in China. Plain water was the main TFI resource (78.8~100.00%), and differences in the plain water intake levels among the four groups were evident (χ2 = 222.027, p < 0.05). The urine osmolality decreased sequentially with increasing TFI values from the LFI1 to HFI2 group, and significant differences in the urine osmolality levels among the four groups were evident (p < 0.05). Meanwhile, the percentage of dehydrated participants decreased from 26.8% in the LFI1 group to 0.0% in the HFI2 group (χ2 = 131.241, p < 0.05). Participants with higher TFI values had higher AFI values (χ2 = 58.386, all p < 0.05), and moderate-intensity correlations were found between TFI and urine osmolality, hydration status, and AFI (all p < 0.05). A large proportion of the participants had insufficient TFIs during the second trimester of pregnancy, and a proportion of the participants were dehydrated. The preliminary analysis showed that the AFI was correlated with the TFI during the second trimester of pregnancy. A sufficient TFI is necessary for pregnant women to improve their hydration status and may have effects on their health. The results can provide appropriate scientific references for the development of beneficial recommendations concerning adequate water intake levels for pregnant women in China.

Investigation of Microplastics (≥10 μm) in Meconium by Fourier Transform Infrared Microspectroscopy

Microplastics are prevalent emerging pollutants with widespread distribution in air, land and water. They have been detected in human stool, blood, lungs, and placentas. However, human fetal microplastic exposure remains largely under-studied. To assess fetal microplastic exposure, we investigated microplastics using 16 meconium samples. We used hydrogen peroxide (H₂O₂), nitric acid (HNO₃) and a combination of Fenton's reagent and HNO₃ pretreatment methods respectively to digest the meconium sample. We analyzed 16 pretreated meconium samples with an ultra-depth three-dimensional microscope and Fourier transform infrared microspectroscopy. The result showed that H₂O₂, HNO₃ and Fenton's reagent combined with HNO₃ pretreatment methods could not digest our meconium samples completely. Alternatively, we developed a novel approach with high digestion efficiency using petroleum ether and alcohol (4:1, v/v), HNO₃ and H₂O₂. This pretreatment method had good recovery and non-destructive advantages. We found no microplastics (≥10 μm) in our meconium samples, indicating that microplastic pollution levels in the fetal living environment are miniscule. Different results between previous studies' and ours underscore that comprehensive and strict quality control are necessary for further studies on microplastic exposure using human bio-samples.

Drug exposure during pregnancy: Current understanding and approaches to measure maternal-fetal drug exposure

Prescription drug use is prevalent during pregnancy, yet there is limited knowledge about maternal-fetal safety and efficacy of this drug use because pregnant individuals have historically been excluded from clinical trials. Underrepresentation has resulted in a lack of data available to estimate or predict fetal drug exposure. Approaches to study fetal drug pharmacology are limited and must be evaluated for feasibility and accuracy. Anatomic and physiological changes throughout pregnancy fluctuate based on gestational age and can affect drug pharmacokinetics (PK) for both mother and fetus. Drug concentrations have been studied throughout different stages of gestation and at or following delivery in tissue and fluid biospecimens. Sampling amniotic fluid, umbilical cord blood, placental tissue, meconium, umbilical cord tissue, and neonatal hair present surrogate options to quantify and characterize fetal drug exposure. These sampling methods can be applied to all therapeutics including small molecule drugs, large molecule drugs, conjugated nanoparticles, and chemical exposures. Alternative approaches to determine PK have been explored, including physiologically based PK modeling, in vitro methods, and traditional animal models. These alternative approaches along with convenience sampling of tissue or fluid biospecimens can address challenges in studying maternal-fetal pharmacology. In this narrative review, we 1) present an overview of the current understanding of maternal-fetal drug exposure; 2) discuss biospecimen-guided sampling design and methods for measuring fetal drug concentrations throughout gestation; and 3) propose methods for advancing pharmacology research in the maternal-fetal population.

Amniotic Fluid Disorders: From Prenatal Management to Neonatal Outcomes

Amniotic fluid volume assessment has become standard in the surveillance of fetal well-being, especially in high-risk pregnancies. Amniotic fluid disorders are a frequent and important topic in fetal and perinatal medicine. However, although important advances have been achieved, many important and challenging questions remain unanswered to date. An abnormally low amniotic fluid volume, referred to as oligohydramnios, has been traditionally considered a possible indicator of placental insufficiency or fetal compromise and is associated with an increased rate of obstetric interventions. An excess of amniotic fluid, referred to as polyhydramnios, may be secondary to fetal or maternal conditions and has been associated with a variety of adverse pregnancy outcomes, especially when it is severe. The ultrasonographic detection of an amniotic fluid disorder should prompt a proper workup to identify the underlying etiology. Data on the association of isolated oligohydramnios or idiopathic polyhydramnios with adverse obstetric and perinatal outcomes are conflicting. While the management of secondary oligohydramnios is usually guided by the underlying condition, the management of isolated oligohydramnios is poorly defined. Similarly, the management of idiopathic and secondary polyhydramnios is not yet standardized. There is an urgent need for randomized clinical trials to provide stronger recommendations on the management of these two common conditions.

Isolated oligohydramnios in previous pregnancy is a risk factor for a placental related disorder in subsequent delivery

BACKGROUND

We aimed to assess the association between isolated oligohydramnios in previous pregnancy and the incidence of placental related complications in subsequent pregnancy.

METHODS

This was a retrospective cohort study of live singleton births from a single university affiliated medical center during an eleven-year period of women with two subsequent deliveries at our center. An analysis of outcomes was performed for all second deliveries, comparing women for whom their first delivery was complicated by isolated oligohydramnios (previous oligohydramnios group), and women without isolated oligohydramnios in their first delivery (control group). Patients for whom their first delivery was complicated by small for gestational age, pregnancy induced hypertension and preterm birth were excluded. The study groups were compared for obstetric and early neonatal outcomes, recurrence of oligohydramnios and a composite of placental related pregnancy complications.

RESULTS

A total of 213 in the previous oligohydramnios group and 5348 in the control group were compared. No differences were found between the groups in maternal age, body mass index, smoking and comorbidities. Gestational age at delivery was, 39.6 ± 1.3 vs. 39.3 ± 1.4 weeks, p = 0.006, in the previous oligohydramnios and controls respectively, although preterm birth rate was similar between the groups. The previous oligohydramnios group had a significantly higher incidence of oligohydramnios in second delivery, aOR 3.37, 95%CI 1.89-6.00, small for gestational age neonates, aOR 1.94, 95% CI 1.16-3.25, and overall placental related disorders of pregnancy, aOR 2.13, 95%CI 1.35-3.35.

CONCLUSION

Pregnancies complicated by isolated oligohydramnios are associated with an increased risk of placental related disorders in subsequent pregnancy. Isolated oligohydramnios may be the first sign of placental insufficiency and an independent manifestation of the placental related complications spectrum.

Cell-Free Amniotic Fluid and Regenerative Medicine: Current Applications and Future Opportunities

Amniotic fluid (AF) provides critical biological and physical support for the developing fetus. While AF is an excellent source of progenitor cells with regenerative properties, recent investigations indicate that cell-free AF (cfAF), which consists of its soluble components and extracellular vesicles, can also stimulate regenerative and reparative activities. This review summarizes published fundamental, translational, and clinical investigations into the biological activity and potential use of cfAF as a therapeutic agent. Recurring themes emerge from these studies, which indicate that cfAF can confer immunomodulatory, anti-inflammatory, and pro-growth characteristics to the target cells/tissue with which they come into contact. Another common observation is that cfAF seems to promote a return of cells/tissue to a homeostatic resting state when applied to a model of cell stress or disease. The precise mechanisms through which these effects are mediated have not been entirely defined, but it is clear that cfAF can safely and effectively treat cutaneous wounds and perhaps orthopedic degenerative conditions. Additional applications are currently being investigated, but require further study to dissect the fundamental mechanisms through which its regenerative effects are mediated. By doing so, rational design can be used to fully unlock its potential in the biotechnology lab and in the clinic.

Efficacy of inhaled Desmopressin in pregnant women with idiopathic oligohydramnios - a randomized controlled trial

The aim of this study was to investigate the therapeutic effect of inhaled Desmopressin (DDAVP) in pregnant women with idiopathic oligohydramnios. This randomized, double-blind clinical trial involved 44 pregnant women at 28-37 weeks of gestation with idiopathic oligohydramnios admitted in 2 academic hospitals in Mashhad, Iran, from 2018 to 2019. In the intervention group, 10µg DDAVP was nasally sprayed. The control group received intravenous maintenance fluid. The hematocrit, electrolytes, blood pressure and urine-specific gravity were evaluated at baseline and 3, 8, and 24 hours later. Amniotic fluid index (AFI) was measured using ultrasound at baseline, 24 and 48 hours later. There was no significant difference in the basic characteristics (age, body mass index, and gestational age) between the two groups. The pattern of changes of AFI (baseline, 24 and 48 hours later) increased in the intervention (4.16±0.86, 7.08±1.453 and 7.76±1.62, p<0.001) and control groups (4.23±0.70, 5.39±1.079 and 5.68±1.10, p<0.001). Serum sodium levels significantly declined in the intervention group (p<0.001) but not in the control group (p=0.07). There were no significant differences in potassium (p=0.89), hematocrit (p=0.23), systolic blood pressure (p=0.21) and diastolic blood pressure (p=0.97). However, urine-specific gravity had an increasing pattern in the intervention group (p<0.001) and a decreasing pattern in the control group (p<0.001). This study showed that Desmopressin inhalation could increase the AFI and urine specific gravity, enhancing oligohydramnios treatment in pregnant women, compared to serum administration.

Amniotic Fluid Classification and Artificial Intelligence: Challenges and Opportunities

A fetal ultrasound (US) is a technique to examine a baby’s maturity and development. US examinations have varying purposes throughout pregnancy. Consequently, in the second and third trimester, US tests are performed for the assessment of Amniotic Fluid Volume (AFV), a key indicator of fetal health. Disorders resulting from abnormal AFV levels, commonly referred to as oligohydramnios or polyhydramnios, may pose a serious threat to a mother’s or child’s health. This paper attempts to accumulate and compare the most recent advancements in Artificial Intelligence (AI)-based techniques for the diagnosis and classification of AFV levels. Additionally, we provide a thorough and highly inclusive breakdown of other relevant factors that may cause abnormal AFV levels, including, but not limited to, abnormalities in the placenta, kidneys, or central nervous system, as well as other contributors, such as preterm birth or twin-to-twin transfusion syndrome. Furthermore, we bring forth a concise overview of all the Machine Learning (ML) and Deep Learning (DL) techniques, along with the datasets supplied by various researchers. This study also provides a brief rundown of the challenges and opportunities encountered in this field, along with prospective research directions and promising angles to further explore.

Procoagulant Activity in Amniotic Fluid Is Associated with Fetal-Derived Extracellular Vesicles

Procoagulant activity in amniotic fluid (AF) is positively correlated with phosphatidylserine (PS) and tissue factor (TF)-expressing(+) extracellular vesicles (EVs). However, it is unknown if pathological fetal conditions may affect the composition, phenotype, and procoagulant potency of EVs in AF. We sought to evaluate EV-dependent procoagulant activity in AF from pregnant people with fetuses with or without diagnosed chromosomal mutations. AF samples were collected by transabdominal amniocentesis and assessed for common karyotype defects (total n = 11, 7 healthy and 4 abnormal karyotypes). The procoagulant activity of AF was tested using a fibrin generation assay with normal pooled plasma and plasmas deficient in factors XII, XI, IX, X, V, and VII. EV number and phenotype were determined by flow cytometry with anti-CD24 and anti-TF antibodies. We report that factor-VII-, X-, or V-deficient plasmas did not form fibrin clots in the presence of AF. Clotting time was significantly attenuated in AF samples with chromosomal mutations. In addition, CD24+, TF+, and CD24+ TF+ EV counts were significantly lower in this group. Finally, we found a significant correlation between EV counts and the clotting time induced by AF. In conclusion, we show that AF samples with chromosomal mutations had fewer fetal-derived CD24-bearing and TF-bearing EVs, which resulted in diminished procoagulant potency. This suggests that fetal-derived EVs are the predominant source of procoagulant activity in AF.

Placental Tissues as Biomaterials in Regenerative Medicine

Placental tissues encompass all the tissues which support fetal development, including the placenta, placental membrane, umbilical cord, and amniotic fluid. Since the 1990s there has been renewed interest in the use of these tissues as a raw material for regenerative medicine applications. Placental tissues have been extensively studied for their potential contribution to tissue repair applications. Studies have attributed their efficacy in augmenting the healing process to the extracellular matrix scaffolds rich in collagens, glycosaminoglycans, and proteoglycans, as well as the presence of cytokines within the tissues that have been shown to stimulate re-epithelialization, promote angiogenesis, and aid in the reduction of inflammation and scarring. The compositions and properties of all birth tissues give them the potential to be valuable biomaterials for the development of new regenerative therapies. Herein, the development and compositions of each of these tissues are reviewed, with focus on the structural and signaling components that are relevant to medical applications. This review also explores current configurations and recent innovations in the use of placental tissues as biomaterials in regenerative medicine.

Extraembryonic Mesenchymal Stromal/Stem Cells in Liver Diseases: A Critical Revision of Promising Advanced Therapy Medicinal Products

Liver disorders have been increasing globally in recent years. These diseases are associated with high morbidity and mortality rates and impose high care costs on the health system. Acute liver failure, chronic and congenital liver diseases, as well as hepatocellular carcinoma have been limitedly treated by whole organ transplantation so far. But novel treatments for liver disorders using cell-based approaches have emerged in recent years. Extra-embryonic tissues, including umbilical cord, amnion membrane, and chorion plate, contain multipotent stem cells. The pre-sent manuscript discusses potential application of extraembryonic mesenchymal stromal/stem cells, focusing on the management of liver diseases. Extra-embryonic MSC are characterized by robust and constitutive anti-inflammatory and anti-fibrotic properties, indicating as therapeutic agents for inflammatory conditions such as liver fibrosis or advanced cirrhosis, as well as chronic inflammatory settings or deranged immune responses.

Comparison of the effectiveness and pregnancy outcomes of labor induction with dinoprostone or single-balloon catheter in term nulliparous women with borderline oligohydramnios

Backgrounds:

At present, there is no consensus on the induction methods in term pregnancy with borderline oligohydramnios. This study aimed to compare the effectiveness and pregnancy outcomes of labor induction with dinoprostone or single-balloon catheter (SBC) in term nulliparous women with borderline oligohydramnios.

Methods:

We conducted a retrospective cohort study from January 2016 to November 2018. During the study period, a total of 244 cases were enrolled. Of these, 103 cases were selected for induction using dinoprostone and 141 cases were selected for induction with SBC. The pregnancy outcomes between the two groups were compared. Primary outcomes were successful vaginal delivery rates. Secondary outcomes were maternal and neonatal adverse events. Multivariate logistic regression was used to assess the risk factors for vaginal delivery failure in the two groups.

Results:

The successful vaginal delivery rates were similar between the dinoprostone group and the SBC group (64.1% [66/103] vs. 59.6% [84/141], P = 0.475), even after adjustment for potential confounding factors (adjusted odds ratio [aOR]: 1.07, 95% confidence interval [CI]: 0.57–2.00, P = 0.835). The incidence of intra-amniotic infection was lower in the dinoprostone group than in the SBC group (1.9% [2/103] vs. 7.8% [11/141], P < 0.001), but the presence of non-reassuring fetal heart rate was higher in the dinoprostone group than in the SBC group (12.6% [13/103] vs. 0.7% [1/141], P < 0.001). Multivariate logistic regression showed that nuchal cord was a risk factor for vaginal delivery failure after induction with dinoprostone (aOR: 6.71, 95% CI: 1.96–22.95). There were three factors related to vaginal delivery failure after induction with SBC, namely gestational age (aOR: 1.51, 95% CI: 1.07–2.14), body mass index (BMI) >30 kg/m² (aOR: 2.98, 95% CI: 1.10–8.02), and fetal weight >3500 g (aOR: 2.49, 95% CI: 1.12–5.50).

Conclusions:

Term nulliparous women with borderline oligohydramnios have similar successful vaginal delivery rates after induction with dinoprostone or SBC, with their advantages and disadvantages. In women with nuchal cord, the risk of vaginal delivery failure is increased if dinoprostone is used in the induction of labor. BMI >30 kg/m², large gestational age, and estimated fetal weight >3500 g are risk factors for vaginal delivery failure after induction with SBC.

Women-specific routes of administration for drugs: A critical overview

The woman's body presents a number of unique anatomical features that can constitute valuable routes for the administration of drugs, either for local or systemic action. These are associated with genitalia (vaginal, endocervical, intrauterine, intrafallopian and intraovarian routes), changes occurring during pregnancy (extra-amniotic, intra-amniotic and intraplacental routes) and the female breast (breast intraductal route). While the vaginal administration of drug products is common, other routes have limited clinical application and are fairly unknown even for scientists involved in drug delivery science. Understanding the possibilities and limitations of women-specific routes is of key importance for the development of new preventative, diagnostic and therapeutic strategies that will ultimately contribute to the advancement of women's health. This article provides an overview on women-specific routes for the administration of drugs, focusing on aspects such as biological features pertaining to drug delivery, relevance in current clinical practice, available drug dosage forms/delivery systems and administration techniques, as well as recent trends in the field.

Pregnancy complicated by central diabetes insipidus and oligohydramnios

This is the fourth reported case of central diabetes insipidus with oligohydramnios. Central diabetes insipidus does not adversely affect pregnancy; it can present with oligohydramnios, which can be improved by treating central diabetes insipidus.

Dietary L-arginine supplementation during days 14-25 of gestation enhances aquaporin expression in the placentae and endometria of gestating gilts

This study tested the hypothesis that dietary L-arginine (Arg) supplementation to pregnant gilts enhanced the expression of water channel proteins [aquaporins (AQPs)] in their placentae and endometria. Gilts were fed twice daily 1 kg of a corn and soybean meal-based diet supplemented with 0.0%, 0.4%, or 0.8% Arg between Days 14 and 25 of gestation. On Days 25 and 60 of gestation, gilts were hysterectomized to obtain placentae and endometria. On Day 25 of gestation, supplementation with 0.4% Arg increased (P < 0.05) the abundance of placental AQP9 protein, whereas supplementation with 0.8% Arg increased (P < 0.05) placental AQP1 and AQP9 proteins, compared with controls. On Day 60 of gestation, supplementation with 0.4% Arg increased (P < 0.05) endometrial AQP1 protein, whereas supplementation with 0.8% Arg increased (P < 0.05) endometrial AQP5 and AQP9 proteins. Supplementation with 0.8% Arg increased the endometrial expression of AQP1, AQP5, and AQP9 proteins located in the luminal epithelium and glandular epithelium of endometria, and placental transport of ³H₂O. Collectively, these results indicate that dietary Arg supplementation stimulates the expression of selective AQPs in porcine placenta and endometria, thereby enhancing water transport from mother to fetus and expanding the chorioallantoic membranes during the period of placentation.

Shoulder and elbow requirements during sagittal reach as a result of changing anthropometry throughout pregnancy

During pregnancy, anthropometric and physiological changes can result in difficulty reaching for and lifting everyday objects. The aims of this study were to determine the changes in sagittal plane anterior reach space (SPARS) and shoulder/elbow strength requirements throughout pregnancy. Seventeen participants were tested through a longitudinal observational cohort study between 16 and 36 weeks gestation in four-week intervals. A 25% decrease in SPARS was observed at the L3-4 torso height. Combined with arm mass increases, shoulder and elbow moment requirements at the minimum and maximum static reach distances significantly increased. However, inverse dynamics analysis determined that mass gains in the arm alone only minimally impact dynamic shoulder moments. Additionally, torso flexion increases throughout pregnancy demonstrates that women are attempting to compensate for decreased SPARS, possibly indicating the additional perceptual importance of reach space in accommodations for pregnant workers.

Aquaporins in insulin resistance and diabetes: More than channels!

Aquaporins (AQPs) are part of the family of the integral membrane proteins. Their function is dedicated to the transport of water, glycerol, ammonia, urea, H₂O₂, and other small molecules across the biological membranes. Although for many years they were scarcely considered, AQPs have a relevant role in the development of many diseases. Recent discoveries suggest, that AQPs may play an important role in the process of fat accumulation and regulation of oxidative stress, two crucial aspects of insulin resistance and type-2 diabetes (T2D).

Insulin resistance (IR) and T2D are multi-faceted systemic diseases with multiple connections to obesity and other comorbidities such as hypertension, dyslipidemia and metabolic syndrome. Both IR and T2D transcends different tissues and organs, creating the maze of mutual relationships between adipose fat depots, skeletal muscle, liver and other insulin-sensitive organs. AQPs with their heterogenous properties, distinctive tissue distribution and documented involvement in both the lipid metabolism and regulation of the oxidative stress appear to be feasible candidates in the search for the explanation to this third-millennium plague. A lot of research has been assigned to adipose tissue AQP7 and liver tissue AQP9, clarifying their relationship and coordinated work in the induction of hepatic insulin resistance. Novel research points also to other aquaporins, such as AQP11 which may be associated with the induction of insulin resistance and T2D through its involvement in hydrogen peroxide transport.

In this review we collected recent discoveries in the field of AQP's involvement in the insulin resistance and T2D. Novel paths which connect AQPs with metabolic disorders can give new fuel to the research on obesity, insulin resistance and T2D - one of the most worrying problems of the modern society.

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Presentation of the current knowledge on the involvement of aquaporins in disease state.

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Overview on latest research regarding insulin resistance and AQPs.

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Conceptualisation of an AQPs network involved regulation of lipid-related metabolism.

The Role of microRNAs Identified in the Amniotic Fluid

AIM

The study aimed to provide an overall view of current data considering the presence of microRNAs in amniotic fluid.

METHODS

The available literature in MEDLINE, regarding the role of the amniotic fluid in pregnancy and fetal development, was searched for related articles including terms such as "microRNA", "Amniotic fluid", "Adverse outcome" and others.

RESULTS

The amniotic fluid has an undoubtedly significant part in fetal nutrition, with a protecting and thermoregulatory role alongside. MicroRNAs have proven to be highly expressed during pregnancy in many body liquids including amniotic fluid and are transferred between cells loaded in exosomes, while they are also implicated in many processes during fetal development and could be potential biomarkers for early prediction of adverse outcomes.

CONCLUSION

Current knowledge reveals that amniotic fluid microRNAs participate in many developmental and physiological processes of pregnancy including proliferation of fibroblasts, fetal development, angiogenesis, cardioprotection, activation of signaling pathways, differentiation and cell motility, while the expression profile of specific microRNAs has a potential prognostic role in the prediction of Down syndrome, congenital hydronephrosis and kidney fibrosis.

Automated ultrasound assessment of amniotic fluid index using deep learning

The estimation of antenatal amniotic fluid (AF) volume (AFV) is important as it offers crucial information about fetal development, fetal well-being, and perinatal prognosis. However, AFV measurement is cumbersome and patient specific. Moreover, it is heavily sonographer-dependent, with measurement accuracy varying greatly depending on the sonographer's experience. Therefore, the development of accurate, robust, and adoptable methods to evaluate AFV is highly desirable. In this regard, automation is expected to reduce user-based variability and workload of sonographers. However, automating AFV measurement is very challenging, because accurate detection of AF pockets is difficult owing to various confusing factors, such as reverberation artifact, AF mimicking region and floating matter. Furthermore, AF pocket exhibits an unspecified variety of shapes and sizes, and ultrasound images often show missing or incomplete structural boundaries. To overcome the abovementioned difficulties, we develop a hierarchical deep-learning-based method, which consider clinicians' anatomical-knowledge-based approaches. The key step is the segmentation of the AF pocket using our proposed deep learning network, AF-net. AF-net is a variation of U-net combined with three complementary concepts - atrous convolution, multi-scale side-input layer, and side-output layer. The experimental results demonstrate that the proposed method provides a measurement of the amniotic fluid index (AFI) that is as robust and precise as the results from clinicians. The proposed method achieved a Dice similarity of 0.877±0.086 for AF segmentation and achieved a mean absolute error of 2.666±2.986 and mean relative error of 0.018±0.023 for AFI value. To the best of our knowledge, our method, for the first time, provides an automated measurement of AFI.

Conventional revolution: the ethical implications of the natural progress of neonatal intensive care to artificial wombs

Research teams have used extra-uterine systems (Biobags) to support premature fetal lambs and to bring them to maturation in a way not previously possible. The researchers have called attention to possible implications of these systems for sustaining premature human fetuses in a similar way. Some commentators have pointed out that perfecting these systems for human fetuses might alter a standard expectation in abortion practices: that the termination of a pregnancy also (inevitably) entails the death of the fetus. With Biobags, it might be possible, some argue, that no woman has the right to expect that outcome if the technology is able to sustain fetal life after an abortion. In order to protect the expectation that the termination of a pregnancy always entails the death of the fetus, Elizabeth Romanis has argued that fetuses sustained in Biobags have a status different than otherwise 'born' children. In support of that view, she argues that these 'gestatelings' are incapable of independent life. This argument involves a misunderstanding of the gestational support involved, as well as a misapprehension of neonatology practice. Here, we argue that any human fetus sustained in a Biobag would be as 'independent' as any other premature infant, and just as 'born'. Neonatologists would seem to have certain presumptive moral responsibilities toward any human fetus gestating in a Biobag. It remains a separate question whether the perfection and widespread application of Biobags for premature human beings would or should alter the expectation that ending a pregnancy also entails fetal death.

Basal Ti level in the human placenta and meconium and evidence of a materno-foetal transfer of food-grade TiO2 nanoparticles in an ex vivo placental perfusion model

Background

Titanium dioxide (TiO₂) is broadly used in common consumer goods, including as a food additive (E171 in Europe) for colouring and opacifying properties. The E171 additive contains TiO₂ nanoparticles (NPs), part of them being absorbed in the intestine and accumulated in several systemic organs. Exposure to TiO₂-NPs in rodents during pregnancy resulted in alteration of placental functions and a materno-foetal transfer of NPs, both with toxic effects on the foetus. However, no human data are available for pregnant women exposed to food-grade TiO₂-NPs and their potential transfer to the foetus. In this study, human placentae collected at term from normal pregnancies and meconium (the first stool of newborns) from unpaired mothers/children were analysed using inductively coupled plasma mass spectrometry (ICP-MS) and scanning transmission electron microscopy (STEM) coupled to energy-dispersive X-ray (EDX) spectroscopy for their titanium (Ti) contents and for analysis of TiO₂ particle deposition, respectively. Using an ex vivo placenta perfusion model, we also assessed the transplacental passage of food-grade TiO₂ particles.

Results

By ICP-MS analysis, we evidenced the presence of Ti in all placentae (basal level ranging from 0.01 to 0.48 mg/kg of tissue) and in 50% of the meconium samples (0.02–1.50 mg/kg), suggesting a materno-foetal passage of Ti. STEM-EDX observation of the placental tissues confirmed the presence of TiO₂-NPs in addition to iron (Fe), tin (Sn), aluminium (Al) and silicon (Si) as mixed or isolated particle deposits. TiO₂ particles, as well as Si, Al, Fe and zinc (Zn) particles were also recovered in the meconium. In placenta perfusion experiments, confocal imaging and SEM-EDX analysis of foetal exudate confirmed a low transfer of food-grade TiO₂ particles to the foetal side, which was barely quantifiable by ICP-MS. Diameter measurements showed that 70 to 100% of the TiO₂ particles recovered in the foetal exudate were nanosized.

Conclusions

Altogether, these results show a materno-foetal transfer of TiO₂ particles during pregnancy, with food-grade TiO₂ as a potential source for foetal exposure to NPs. These data emphasize the need for risk assessment of chronic exposure to TiO₂-NPs during pregnancy.

Cloned pig fetuses exhibit fatty acid deficiency from impaired placental transport

Cloned pig fetuses produced by somatic cell nuclear transfer show a high incidence of erroneous development in the uteri of surrogate mothers. The mechanisms underlying the abnormal intrauterine development of cloned pig fetuses are poorly understood. This study aimed to explore the potential causes of the aberrant development of cloned pig fetuses. The levels of numerous fatty acids in allantoic fluid and muscle tissue were lower in cloned pig fetuses than in artificial insemination-generated pig fetuses, thereby suggesting that cloned pig fetuses underwent fatty acid deficiency. Cloned pig fetuses also displayed trophoblast hypoplasia and a reduced expression of placental fatty acid transport protein 4 (FATP4), which is the predominant FATP family member expressed in porcine placentas. This result suggested that the placental fatty acid transport functions were impaired in cloned pig fetuses, possibly causing fatty acid deficiency in cloned pig fetuses. The present study provides useful information in elucidating the mechanisms underlying the abnormal development of cloned pig fetuses.

Antibiotic therapy as personalized medicine - general considerations and complicating factors

The discovery of antibiotic drugs is considered one of the previous century's most important medical discoveries (Medicine's 10 greatest discoveries. New Haven, CT: Yale University Press, 1998: 263). Appropriate use of antibiotics saves millions of lives each year and prevents infectious complications for numerous people. Still, infections kill unacceptable many people around the world, even in developed countries with easy access to most antibiotic drugs. Optimal use of antibiotics is dependent on the identification of primary and secondary focus, and knowledge on which pathogens to expect in a specific infectious syndrome and information on general patterns of regional antibiotic resistance. Furthermore, sampling for microbiological analysis, knowledge of patient immune status and organ functions, travel history, pharmacokinetics and -dynamics of the different antibiotics and possible biofilm formation are among several factors involved in antibiotic therapy of infectious diseases. The present review aims at describing important considerations when using antibacterial antibiotics and to describe how this is becoming substantially more personalized. The parameters relevant in considering the optimal use of antibiotics to treat infections are shown in Fig. 1 - leading to the most relevant antibiotic therapy for that specific patient. To illustrate this subject, the present review's focus will be on challenges with optimal dosing of antibiotics and risks of underdosing. Especially, in cases highly challenging for achieving the aimed antibiotic effect against bacterial infections - this includes augmented renal clearance (ARC) in sepsis, dosing challenges of antibiotics in pregnancy and against biofilm infections.

Keratinocytes are mechanoresponsive to the microflow-induced shear stress

Here, we have reported that keratinocytes respond to the microflow-induced shear stress both at the collective and individual cell level. Using a microfluidic setup, we categorically showed that low shear stress of magnitude 0.06 dyne/cm² could induce morphological variation and cytoskeletal reorganization in keratinocyte, whereas higher shear stress (6 dyne/cm² ) resulted in cellular disruption. Using a series of blocker molecules specific to different mechanotransducers, we demonstrated the pivotal role of actin network in keratinocyte mechanoresponsiveness in conjugation with myosin and lipid rafts. Flow-induced shear stress also induced significant elevation in E-cadherin and Zonula occludens-1 (ZO-1) expression levels. We further showed that under the influence of shear stress, the extent of colocalization of E-cadherin and ZO-1 was more at the cell-cell junction that indicates an improvement in the epithelial phenotype. An increase in the expression of nuclear lamin was also observed in the sheared cells that suggest the transmission of mechanical signals to the nucleus. It is envisioned that this study may find its application in basic and applied organogenesis of the epidermis.

Identification of amniotic fluid metabolomic and placental transcriptomic changes associated with abnormal development of cloned pig fetuses

Piglets cloned by somatic cell nuclear transfer (SCNT) show a high incidence of malformations and a high death rate during the perinatal period. To investigate the underlying mechanisms for abnormal development of cloned pig fetuses, we compared body weight, amniotic fluid (AF) metabolome, and placental transcriptome between SCNT- and artificial insemination (AI)-derived pig fetuses. Results showed that the body weight of SCNT pig fetuses was significantly lower than that of AI pig fetuses. The identified differential metabolites between the two groups of AF were mainly involved in bile acids and steroid hormones. The levels of all detected bile acids in SCNT AF were significantly higher than those in AI AF. The increase in the AF bile acid levels in SCNT fetuses was linked with the downregulation of placental bile acid transporter expression and the abnormal development of placental folds (PFs), both of which negatively affected the transfer of bile acids from AF across the placenta into the mother's circulation. Alteration in the AF steroid hormone levels in cloned fetuses was associated with decreased expression of enzymes responsible for steroid hormone biosynthesis in the placenta. In conclusion, cloned pig fetuses undergo abnormal intrauterine development associated with alteration of bile acid and steroid hormone levels in AF, which may be due to the poor development of PFs and the erroneous expression of bile acid transporters and enzymes responsible for steroid hormone biosynthesis in the placentas.

Robust increases in erythropoietin production by the hypoxic fetus is a response to protect the brain and other vital organs

Fetal erythropoietin (EPO), in addition to regulating erythropoiesis, has also tissue-protective properties based on its anti-inflammatory, anti-apoptotic, antioxidant, and neurotrophic effects. Notably, EPO concentrations needed for tissue protection are 100-1000 times higher than concentrations needed for regulating erythropoiesis. This dual effect of EPO is based on EPO-receptor (EPO-R) isoforms, which differ structurally and functionally. We hypothesize in this Integrated Mechanism Review that during severe fetal hypoxia the observed, but poorly understood, marked increases of fetal plasma EPO concentrations occur to protect the brain, heart, and other vital fetal organs. We further hypothesize that the concurrent marked increases of EPO in the amniotic fluid during fetal hypoxia, occur to protect newborn infants from necrotizing enterocolitis. This review presents experimental and clinical evidence in support of these hypotheses and points out unknown or poorly understood functions of EPO in the fetus. If these novel hypotheses are correct, the importance of fetal EPO as an antenatal hypoxia biomarker will become apparent. It will also likely point the way to important diagnostic and therapeutic fetal and neonatal interventions.

Loss of Aquaporin-3 in Placenta and Fetal Membranes Induces Growth Restriction in Mice

Aquaporin (AQP) 3, a facilitated transporter of water and glycerol, expresses in placenta and fetal membranes, but the detailed localization and function of AQP3 in placenta remain unclear. To elucidate a role of AQP3 in placenta, we defined the expression and cellular localization of AQP3 in placenta and fetal membranes, and investigated the structural and functional differences between wild-type and AQP3 null mice. Gestational sacs were removed during mid-gestational period and amniotic fluid was aspirated for measurements of volume and composition. Fetuses with attached placenta and fetal membranes were weighed and processed for histological assessment. AQP3 strongly expressed in basolateral membrane of visceral yolk sac cells of fetal membrane, the syncytiotrophoblasts of the labyrinthine placenta and fetal nucleated red blood cell membrane. Mice lacking AQP3 did not exhibit a significant defect in differentiation of trophoblast stem cells and normal placentation. However, AQP3 null fetuses were smaller than their control litter mates in spite of a decrease in litter size. The total amniotic fluid volume per gestational sac was reduced, but the amniotic fluid-to-fetal weight ratio was increased in AQP3 null mice compared with wild-type mice. Glycerol, free fatty acid and triglyceride levels in amniotic fluid of AQP3 null mice were significantly reduced, whereas lactate level increased when compared to those of wild-type mice. These results suggest a role for AQP3 in supplying nutrients from yolk sac and maternal blood to developing fetus by facilitating transport of glycerol in addition to water, and its implication for the fetal growth in utero.

Atlas of tissue- and developmental stage specific gene expression for the bovine insulin-like growth factor (IGF) system

The insulin-like growth factor (IGF) axis is fundamental for mammalian growth and development. However, no comprehensive reference data on gene expression across tissues and pre- and postnatal developmental stages are available for any given species. Here we provide systematic promoter- and splice variant specific information on expression of IGF system components in embryonic (Day 48), fetal (Day 153), term (Day 277, placenta) and juvenile (Day 365–396) tissues of domestic cow, a major agricultural species and biomedical model. Analysis of spatiotemporal changes in expression of IGF1, IGF2, IGF1R, IGF2R, IGFBP1-8 and IR genes, as well as lncRNAs H19 and AIRN, by qPCR, indicated an overall increase in expression from embryo to fetal stage, and decrease in expression from fetal to juvenile stage. The stronger decrease in expression of lncRNAs (average ―16-fold) and ligands (average ―12.1-fold) compared to receptors (average ―5.7-fold) and binding proteins (average ―4.3-fold) is consistent with known functions of IGF peptides and supports important roles of lncRNAs in prenatal development. Pronounced overall reduction in postnatal expression of IGF system components in lung (―12.9-fold) and kidney (―13.2-fold) are signatures of major changes in organ function while more similar hepatic expression levels (―2.2-fold) are evidence of the endocrine rather than autocrine/paracrine role of IGFs in postnatal growth regulation. Despite its rapid growth, placenta displayed a more stable expression pattern than other organs during prenatal development. Quantitative analyses of contributions of promoters P0-P4 to global IGF2 transcript in fetal tissues revealed that P4 accounted for the bulk of transcript in all tissues but skeletal muscle. Demonstration of IGF2 expression in fetal muscle and postnatal liver from a promoter orthologous to mouse and human promoter P0 provides further evidence for an evolutionary and developmental shift from placenta-specific P0-expression in rodents and suggests that some aspects of bovine IGF expression may be closer to human than mouse.

High-fat diet effects on amniotic fluid volume and amnion aquaporin expression in non-human primates

Western style, high-fat diet (HFD) and associated high lipid levels have deleterious effects on fetal and placental development independent of maternal obesity and/or diabetes. Our objectives were to determine whether HFD without development of obesity would alter amniotic fluid volume (AFV) and amnion aquaporin (AQP) expression in a non-human primate model. Japanese macaques were fed either a control diet or HFD before and during pregnancy. The four quadrant amniotic fluid index (AFI) was used as an ultrasonic estimate of AFV at 120 days gestation. Amnion samples were collected at 130 days gestation by cesarean section and AQP mRNA levels were determined by quantitative RT-PCR. Similar to that in human, AQP1, AQP3, AQP8, AQP9, and AQP11 were expressed in the macaque amnion with significant differences in levels among AQPs. In macaque, neither individual AQPs nor expression profiles of the five AQPs differed between control and non-obese HFD animals. There were regional differences in AQP expression in that, AQP1 mRNA levels were highest and AQP8 lowest in reflected amnion while AQP3, AQP9, and AQP11 were not different among amnion regions. When subdivided into control and HFD groups, AQP1 mRNA levels remain highest in the reflected amnion of both groups. The HFD did not significantly affect the AFI, but AFI was positively correlated with AQP11 mRNA levels independent of diet. Collectively, these data suggest that HFD in pregnant non-obese individuals may have at most modest effects on AFV as the AFI and amnion AQP expression are not substantially altered.

Amniotic Fluid INSL3 Measured During the Critical Time Window in Human Pregnancy Relates to Cryptorchidism, Hypospadias, and Phthalate Load: A Large Case-Control Study

The period of the first to second trimester transition in human pregnancy represents a sensitive window for fetal organogenesis, particularly in regard to the development of the male reproductive system. This is a time of relative analytical inaccessibility. We have used a large national biobank of amniotic fluid samples collected at routine amniocentesis to determine the impacts of exogenous endocrine disruptor load on specific fetal biomarkers at this critical time. While adrenal and testicular steroids are highly correlated, they are also mostly positively influenced by increasing phthalate load, represented by the metabolites 7cx-MMeHP and 5cx-MEPP, by perfluorooctane sulfonate (PFOS) exposure, and by smoking, suggesting an adrenal stress response. In contrast, the testis specific biomarkers insulin-like peptide 3 (INSL3) and androstenedione are negatively impacted by the phthalate endocrine disruptors. Using a case-control design, we show that cryptorchidism and hypospadias are both significantly associated with increased amniotic concentration of INSL3 during gestational weeks 13-16, and some, though not all steroid biomarkers. Cases are also linked to a specifically increased variance in the Leydig cell biomarker INSL3 compared to controls, an effect exacerbated by maternal smoking. No influence of phthalate metabolites or PFOS was evident on the distribution of cases and controls. Considering that several animal and human studies have shown a negative impact of phthalate load on fetal and cord blood INSL3, respectively, the present results suggest that such endocrine disruptors may rather be altering the relative dynamics of testicular development and consequent hormone production, leading to a desynchronization of tissue organization during fetal development. Being born small for gestational age appears not to impact on the testicular biomarker INSL3 in second trimester amniotic fluid.

Unitary Physiology

The common relationships among a great variety of biological phenomena seem enigmatic when considered solely at the level of the phenotype. The deep connections in physiology, for example, between the effects of maternal food restriction in utero and the subsequent incidence of metabolic syndrome in offspring, the effects of microgravity on cell polarity and reproduction in yeast, stress effects on jellyfish, and their endless longevity, or the relationship between nutrient abundance and the colonial form in slime molds, are not apparent by phenotypic observation. Yet all of these phenomena are ultimately determined by the Target of Rapamycin (TOR) gene and its associated signaling complexes. In the same manner, the unfolding of evolutionary physiology can be explained by a comparable application of the common principle of cell-cell signaling extending across complex developmental and phylogenetic traits. It is asserted that a critical set of physiologic and phenotypic adaptations emanated from a few crucial, ancestral receptor gene duplications that enabled the successful terrestrial transition of vertebrates from water to land. In combination, mTor and its cognate receptors and a few crucial genetic duplications provide a mechanistic common denominator across a diverse spectrum of biological responses. The proper understanding of their purpose yields a unified concept of physiology and its evolutionary development. © 2018 American Physiological Society. Compr Physiol 8:761-771, 2018.

An EXTrauterine environment for neonatal development: EXTENDING fetal physiology beyond the womb

Extreme prematurity is a major cause of neonatal mortality and morbidity, and remains an unsolved clinical challenge. The development of an artificial womb, an extrauterine system recreating the intrauterine environment, would support ongoing growth and organ maturation of the extreme preterm fetus and would have the potential to substantially improve survival and reduce morbidity. Previous efforts toward the development of such a system have demonstrated the ability to maintain the isolated fetus for short periods of support, but have failed to achieve the long-term stability required for clinical application. Here we describe our initial experiments demonstrating the stable support of fetal lambs developmentally equivalent to the extreme premature infant for up to four weeks with stable hemodynamics, growth, and development. The achievement of long-term physiologic support of the fetus in an extrauterine system has the potential to fundamentally change the management and clinical outcome of the extreme premature infant.

A Physiologically-Based Pharmacokinetic Model to Predict Human Fetal Exposure for a Drug Metabolized by Several CYP450 Pathways

BACKGROUND

Pregnant women and their fetuses are exposed to numerous drugs; however, they are orphan populations with respect to the safety and efficacy of drugs. Therefore, the prediction of maternal and fetal drug exposure prior to administration would be highly useful.

METHODS

A physiologically-based pharmacokinetic (PBPK) model for nevirapine, which is metabolized by the cytochrome P450 (CYP) 3A4, 2B6 and 2D6 pathways, was developed to predict maternal and fetal pharmacokinetics (PK). The model was developed in both non-pregnant and pregnant women, and all physiological and enzymatic changes that could impact nevirapine PK were taken into account. Transplacental parameters estimated from ex vivo human placenta perfusion experiments were included in this PBPK model. To validate the model, observed maternal and cord blood concentrations were compared with predicted concentrations, and the impact of fetal clearance on fetal PK was investigated.

RESULTS

By implementing physiological changes, including CYP3A4, 2D6 and 2B6 inductions, we predicted a clearance increase of 21 % in late pregnancy. The PBPK model successfully predicted the disposition for both non-pregnant and pregnant populations. Parameters obtained from the ex vivo experiments allowed the prediction of nevirapine concentrations that matched observed cord blood concentrations. The fetal-to-maternal area under the curve ratio (0-24 h interval) was 0.77, and fetal metabolism had no significant effect on fetal PK.

CONCLUSIONS

The PBPK approach is a useful tool for quantifying a priori the drug exposure of metabolized drugs during pregnancy, and can be applied to evaluate alternative dosing regimens to optimize drug therapy. This approach, including ex vivo human placental perfusion parameters, is a promising approach for predicting human fetal exposure.

Perinatal outcomes in uncomplicated late preterm pregnancies with borderline oligohydramnios

PURPOSE

The purpose of this study is to determine the adverse perinatal outcomes in uncomplicated late preterm pregnancies with borderline oligohydramnios.

METHODS

A total of 430 pregnant women with an uncomplicated singleton pregnancy at a gestational age of 34 + 0-36 + 6 weeks were included. Borderline oligohydramnios was defined as an amniotic fluid index (AFI) of 5.1-8 cm, which was measured using the four-quadrant technique. Adverse perinatal outcomes were compared between the borderline and normal AFI groups.

RESULTS

Approximately 107 of the 430 pregnant women were borderline AFI, and 323 were normal AFI. The demographic and obstetric characteristics were similar in both groups. Delivery <37 weeks, cesarean delivery for non-reassuring fetal heart-rate testing, meconium-stained amniotic fluid, Apgar 5 min <7, transient tachypnea of the newborn, respiratory distress syndrome, neonatal intensive care unit, and hyperbilirubinemia were not statistically different between the groups (p = .054, p = .134, p = .749, p = 0.858, p = .703, p = .320, p = .185, and p = .996, respectively). Although gestational age was full-term, induction of labor rates were significantly higher in the borderline AFI group (p = .040). In addition, fetal renal artery pulsatility index pulsatility index (PI) was significantly lower in the borderline AFI group than in the normal AFI group (p = .014).

CONCLUSION

Our results indicated that borderline AFI was not a risk for adverse perinatal outcomes in uncomplicated, late preterm pregnancies.

Nanomaterials engineering for drug delivery: a hybridization approach

The last twenty years have witnessed great advances in biology, medicine, and materials science, leading to the development of various nanoparticle (NP)-mediated drug delivery systems. Innovation in materials science has led the generation of biodegradable, biocompatible, stimuli-responsive, and targeted delivery systems. However, currently available nanotherapeutic technologies are not efficient, which has culminated in the failure of their clinical trials. Despite huge efforts devoted to drug delivery nanotherapeutics, only a small amount of the injected material could reach the desired target. One promising strategy to enhance the efficiency of NP drug delivery is to hybridize multiple materials, where each component could play a critical role in an efficient multipurpose delivery system. This review aims to comprehensively cover different techniques, materials, advantages, and drawbacks of various systems to develop hybrid nano-vesicles for drug delivery. Attention is finally given to the hybridization benefits in overcoming the biological barriers for drug delivery. It is believed that the advent of modern nano-formulations for multifunctional hybrid carriers paves the way for future advances to achieve more efficient drug delivery systems.