Constructing artificial gap junctions to mediate intercellular signal and mass transport.

Natural gap junctions are a type of channel protein responsible for intercellular signalling and mass communication. However, the scope of applications for these proteins is limited as they cannot be prepared at a large scale and are unable to spontaneously insert into cell membranes in vitro. The construction of artificial gap junctions may provide an alternative strategy for preparing analogues of the natural proteins and bottom-up building blocks necessary for the synthesis of artificial cells. Here we show the construction of artificial gap junction channels from unimolecular tubular molecules consisting of alternately arranged positively and negatively charged pillar[5]arene motifs. These molecules feature a hydrophobic-hydrophilic-hydrophobic triblock structure that allows them to efficiently insert into two adjacent plasma membranes and stretch across the gap between the two membranes to form gap junctions. Similar to natural gap junction channels, the synthetic channels could mediate intercellular signal coupling and reactive oxygen species transmission, leading to cellular activity.

Multiplexed analysis of gene expression and chromatin accessibility of human umbilical cord blood using scRNA-Seq and scATAC-Seq.

Nowadays, umbilical cord blood (UCB) cells has been increasingly replacing fetal and adult-derived cells in adoptive cell therapy. However, gene expression and chromatin accessibility in umbilical cord blood cells has not yet been fully elucidated. In this study, we used an integration of scRNA-seq with the scATAC-seq technology to perform unbiased analysis of UCBCs over developmental time from 31 gestational week (GW) to 37 GW in humans. We identified several distinct cell types (erythroid cell, T cell, B cell, erythroid precursor cells, NK cell, and endothelial progenitor cell) and subpopulations (6 different clusters of erythroid cells) in UCB cells. In addition, we also identified a series of differentially expressed genes and chromatin accessibility in each cell type between different gestational weeks. Interestingly, the gene expression pattern of umbilical cord blood cells from normal fetuses of similar gestational weeks were more consistent. In conclusion, our analysis presents a better understanding of the chromatin landscape and regulatory networks in UCB cells.

Aortic balloon occlusion for controlling intraoperative hemorrhage in patients with placenta previa increta/percreta.

BACKGROUND/AIMS: To investigate whether abdominal aortic balloon occlusion (ABO) effectively reduces intraoperative hemorrhage in patents with placenta previa increta/increta. METHODS: Forty-three women were diagnosed as placenta previa increta/percreta by ultrasound and MRI. These patients' assessments were taken by their chief physician, and they were under necessity of previous cesarean section as confirmed by the committee of experts during consultation. There was no significant difference in disease risk rating between them in whole process. Although our department provided a more appropriate method, 10 of 43 patients chose intraoperative aortic balloon occlusion (IABO). Other 33 patients who refused that suggestion were considered as control group. Fully informed consents were obtained from all patients in this study group. The intraoperative blood loss, blood transfusion, rate of hysterectomy and complications of mothers and fetus of IABO group and control group were analyzed. RESULTS: The median intraoperative blood loss was 1000 ml in the IABO group compared with 2000 ml in the control group (p < 0.05). The median volume of transfused red blood cells was 1100 ml in the IABO group compared with 2000 ml in the control group (p < 0.05). 33.3% (11/33) patients in the control group had hemorrhagic shock, and one of them suffered from cardiac arrest intraoperatively because of severe bleeding. However, none of these serious events occurred in the IABO group (p < 0.05). The hysterectomy rate was 70% (7/10) in the IABO group and 63.3% (21/33) in the control group (p > 0.05). No IABO-related complications were observed in the mother and fetus. CONCLUSION: IABO is an effective and safe method to control intraoperative blood loss and blood transfusion in patients with placenta previa increta/percreta.

[Clinical significance of intermittent sinusoidal fetal heart rate at third trimester].

OBJECTIVE: To investigate clinical significance of intermittent sinusoidal fetal heart rate at third trimester. METHODS: From Jan 2002 to Dec 2010, 48 pregnant women at 33 to 41 gestational weeks undergoing electronic fetal heart rate (FHR) monitoring presented with intermittent sinusoidal FHR in Department of Obstetrics and Gynecology, Second School of Clinical Medicine, Jinan University were enrolled in this retrospective study. Twenty-one cases were categorized into continuous group (i.e. with sinusoidal feature and a constant duration ≥ 10 minutes), while the other 27 cases were categorized into intermittent group (i.e. with a duration < 10 minutes). In the mean time, 76 normal cases were chosen randomly matched as control group. Blood gas and hemoglobin were measured in umbilical artery after fetal head delivery. General neurological system examination were performed in those fetus in hospitalization. The outcome of those fetuses was compared. RESULTS: (1) Neonatal complications: the rate of asphyxia, meconium-stained amniotic fluid and fetal anemia were 63% (17/27), 33% (9/27) and 63% (17/27) in group of intermittent sinusoidal FHR, which were significantly higher than 1% (1/76), 4% (3/76), 3% (2/76) in control group (P < 0.05). When compared with 67% (14/21), 52% (11/21), 76% (16/21) in group of continuous sinusoidal, the statistical difference were not observed (P > 0.05). (2) Blood gas in neonate: the rates of pH less than 7 were 18% (5/27) in intermittent group, 52% (11/21) in continuous group and 0 in control group, which all reached statistical difference among those three groups (P < 0.05). (3) Brain damage and death: the rates of brain damage and death were 48% (13/27) and 11% (3/27) in intermittent group, 81% (17/21) and 43% (9/21) in continuous group, and 0 in control group, which all showed significant difference between them (P < 0.05). CONCLUSION: Intermittent and continuous sinusoidal FHR are typical graphics of severe fetal anemia at third trimester. Intermittent sinusoidal FHR is indicative of serious fetal hypoxia.

Expression of macrophage inflammatory protein-1α and monocyte chemoattractant protein-1 in glioma-infiltrating microglia: involvement of ATP and P2X7 receptor.

Chemokines can be produced by gliomas, which mediate the infiltration of microglia, a characteristic feature of glioma-associated neuropathogenesis. ATP that is released at a high level from glioma has been reported to play a regulatory role in chemokine production in cultured glioma cells. The objective of this study was to define the potential role of extracellular ATP in the regulation of macrophage inflammatory protein-1α (MIP-1α) and monocyte chemoattractant protein-1(MCP-1) expression in glioma-associated microglia/macrophages. The results showed that Iba1(+) and ED1(+) microglia existed in the tumor at 3 and 7 day after injection of C6 glioma cells into the rat cerebral cortex (dpi). ED1(+) microglia/macrophages or Iba1(+) microglia in the glioma were also colocalized to MIP-1α- and MCP-1-expressing cells. In vitro study indicated that treatment with ATP and BzATP (an agonist for ATP ionotropic receptor P2X7R) caused an increase in the intracellular levels of microglial MIP-1α and MCP-1. By using an extracellular Ca(2+) chelator (EGTA) and P2X7R antagonists, oxidized ATP (oxATP) and brilliant blue G (BBG), we demonstrated that BzATP-induced production of MIP-1α and MCP-1 levels was due to P2X7R activation and Ca(2+) -dependent regulation. Coadministration of C6 glioma cells and oxATP into the rat cerebral cortex resulted in a reduction of MIP-1α- and MCP-1-expressing microglia/macrophages. We suggest, based on the results from in vivo and in vitro studies, that a massive amount of ATP molecules released in the glioma tumor site may act as the regulator with P2X7R signaling that increases MIP-1α and MCP-1 expression in tumor-infiltrating microglia/macrophages.

[An investigation on the transmission routes and early diagnosis of intrauterine infection induced by hepatitis B virus].

OBJECTIVES: To analyze the relationship between the fetus infection and HBV M, HBV DNA in amniotic fluid, umbilical cord blood, maternal blood and placenta, and to explore the mechanism of vertical transmission of HBV. METHODS: Immunonetric assay and nucleic acid amplification hybri-comb were used. Both HBV M and HBV DNA were detected in amniotic fluid, vein blood, umbilical cord blood for each of 65 HBV-positive women in their different gestational periods, while immunohistochemical analysis was carried out on the tissue of placenta, liver, lung or heart from each abortive fetus/dead infant in the case. RESULTS: For all of the 65 HBsAg-positive women in their different gestational periods, the detected positive rate of HBsAg was 21.50% in amniotic fluid, and 20.00% in umbilical blood. The positive rate of HBsAg, HBeAg, Anti-HBc and HBV DNA detected in blood, amniotic fluid and umbilical blood was 6.15%. The cases with positive HBsAg, Anti-HBe, Anti-HBc and negative HBV DNA were in a percentage of 13.85%. Immunohistochemical analysis on placentas after birth/abortion as well as the tissues of livers, lungs, hearts of the fetuses/dead infants in 4 cases of pregnant women with positive HBsAg, HBeAg, Anti-HBc or HBV DNA in blood, amniotic fluid or umbilical blood showed that HBsAg, HBcAg positive cells in the scope could be seen in every layer of the tissue of placenta, in the hepatic/pulmonary tissue, but not in the cardiac tissue. CONCLUSION: The infection in amniotic fluid or placenta relates to HBV infection in fetus; intrauterine HBV may result in infection in organs such as blood, liver, or lung of a fetus; infection in the amniotic fluid may be another key route of the intrauterine infection of fetus, and the detection on HBV M or HBV DNA in amniotic may be used as one of diagnostic proofs of HBV infection of fetus in its early stage.

Prophylaxis of neonatal respiratory distress syndrome by intra-amniotic administration of pulmonary surfactant.

BACKGROUND: Neonatal respiratory distress syndrome (NRDS) is caused by a deficiency in pulmonary surfactant (PS) and is one of the main reasons of neonatal mortality. This study was conducted to evaluate the efficacy and safety of intra-amniotic administration of pulmonary surfactant for prophylaxis of NRDS. METHODS: Forty-five pregnant women who were due for preterm delivery and whose fetuses' lungs proved immature were divided into two groups. Fifteen women (study group) were administered one dose of pulmonary surfactant injected into the amniotic cavity and delivered within several hours. Nothing was injected into the amniotic cavity of 30 women of the control group. The proportion of neonatal asphyxia, NRDS, mortality and the time in hospital were analyzed to determine if there was any difference between the two groups. RESULTS: There was no significant difference between the two groups for neonatal asphyxia. Foam tests showed that higher proportion of neonates in the study group than in the control group (56.3% vs 13.3%, P < 0.05) had lung maturity. A greater number of control neonates (11/30, 32.3%) had NRDS, compared with the neonates given PS via the amniotic cavity before delivery (1/16, 6.3%, P < 0.05). The neonates in the study group spent nearly 10 days less in hospital than the control group [(32.4 +/- 7.6) days vs (42.0 +/- 15.7) days, P < 0.05], but the difference in mortality between the two groups was not statistically significant. CONCLUSIONS: Intra-amniotic administration of pulmonary surfactant can significantly reduce the proportion of NRDS and the time in hospital of preterm neonates. Whether this method can reduce the mortality of preterm neonates needs to be evaluated further. Intra-amniotic administration of pulmonary surfactant provides an additional effectual means for NRDS prophylaxis.