SILAR Growth of ZnO NSs/CdS QDs on the Optical Fiber-Based Opto-Electrode with Guided In Situ Light and Its Application for the "Signal-On" Detection of Inflammatory Cytokine.

In this study, a novel integrated photoelectrochemical (PEC) sensor platform was proposed, utilizing an optical fiber (OF) as the working electrode for guided in situ light. A CdS quantum dots (QDs)/ZnO nanosheets (NSs) n-n heterojunction was quickly and easily constructed on the OF surface by successive ionic layer adsorption and reaction (SILAR). Au nanoparticles (NPs)@dsDNA as a capturing probe were modified on the CdS QDs/ZnO NSs@OF (CZ@OF). Due to the energy transfer between Au NPs@dsDNA and CdS QDs, the resultant opto-electrode has a lower background near zero, enabling the "signal-on" detection of biomarkers (interleukin-6 (IL-6) as a model). The OF-PEC biosensor demonstrated a wide linear range from 1 to 100 pg mL-1 with a regression coefficient (R2) of 0.9958 and an impressive detection limit (LOD) of 0.19 pg mL-1. More significantly, the proposed OF-PEC can be successfully used for the detection of IL-6 in serum samples from patients with pulmonary arterial hypertension, and it showed consistency and is more sensitive to trace concentrations compared to BD FACSCanto II flow cytometry used at the hospital. This holds significance for an early disease diagnosis. Therefore, the proposed OF-PEC not only achieves integration of the light source and sensing interface but also enables sensitive and accurate "signal-on" detection of IL-6. Furthermore, due to the flexibility and remote detection capabilities of OF, the application of OF-PEC is expected to be expanded more widely. This approach opens up possibilities for advances in PEC sensing.

Photoelectrochemical/Colorimetric Dual-Mode Specific Detection of Staphylococcus aureus Based on the Enzymatic Reaction Triggered by Catalase from Lysed Bacteria.

Staphylococcus aureus (S. aureus) is abundant in nature and frequently leads to various health issues. Bacteriophages as obligate intracellular parasites of bacteria have the ability to specifically identify and infect S. aureus, causing bacterial lysis and the release of endogenous catalase (CAT). The released CAT triggers the conversion of H2O2 into O2 and H2O, resulting in a notable decrease in UV absorption at 570 nm and a concurrent surge in photocurrent. On the basis of this, a photoelectrochemical/colorimetric dual-mode biosensor for the detection of S. aureus was developed. In the photoelectric detection mode, the reactions involving endogenous enzymes occur directly in the solution, requiring only the simple drop-coating of TiO2@CdS onto the indium tin oxide (ITO) electrode surface. There was no need for immobilizing additional biomolecules, thereby significantly minimizing nonspecific adsorption and improving the biosensor's stability and reproducibility. For colorimetry, we utilized a cost-effective and operationally simple approach based on KI and starch. Remarkably, this photoelectrochemical/colorimetry exhibited a linear range of 102-109 CFU/mL for S. aureus, achieving detection limits of 7 and 10 CFU/mL, respectively. Herein, phage identification ensures the specific detection of live S. aureus, thereby effectively mitigating the potential for false signals. The dual-signal readout mode improves the detection accuracy and reliability. In conclusion, this present method offers numerous advantages, including simplicity, time-efficiency, cost-effectiveness, high specificity, and therefore excellent accuracy.

Unravelling High Water Vapor-Induced Inhibitory Effects on Pt/Co3O4 Catalysts toward Benzene Oxidation.

Water vapor inevitably exists in the environment, which causes adverse impacts on many crucial chemical reactions. However, high water vapor of up to 10 vol %─relevant to a broad spectrum of industrial practices-for catalytic implications has been less investigated or neglected. As such, we explored an industry-relevant, humidity-highly sensitive benzene oxidation only in the presence of 10 vol % water vapor using the well-established Pt/Co3O4 catalysts, to bring such an important yet ignored topic to the forefront. Results revealed that Pt/Co3O4 catalysts possessing higher contents of Pt nanoparticles exhibited marked tolerance to water vapor interference. Under an incomplete benzene conversion condition, the input of 10 vol % water vapor indeed impaired the catalytic performance of Pt/Co3O4 catalyst significantly, which, in fact, was caused by the unfavorable formation of carboxylate species covering the catalyst's surface engendering irrecoverable activity loss, instead of the well-accepted water competitive adsorption. While such activity loss can be restored by elevating the reaction to a higher temperature. This study helps us to understand the compromised catalytic activity caused by high humidity, urging the systematic evaluation of well-established catalyst systems in high water vapor-contained conditions and pressing the development of water-tolerant catalysts for real-life application consideration.

Ultrathin LayCoOx Nanosheets with High Porosity Featuring Boosted Catalytic Oxidation of Benzene: Mechanism Elucidation via an Experiment-Theory Combined Paradigm.

Designing transition-metal oxides for catalytically removing the highly toxic benzene holds significance in addressing indoor/outdoor environmental pollution issues. Herein, we successfully synthesized ultrathin LayCoOx nanosheets (thickness of ∼1.8 nm) with high porosity, using a straightforward coprecipitation method. Comprehensive characterization techniques were employed to analyze the synthesized LayCoOx catalysts, revealing their low crystallinity, high surface area, and abundant porosity. Catalytic benzene oxidation tests demonstrated that the La0.029CoOx-300 nanosheet exhibited the most optimal performance. This catalyst enabled complete benzene degradation at a relatively low temperature of 220 °C, even under a high space velocity (SV) of 20,000 h-1, and displayed remarkable durability throughout various catalytic assessments, including SV variations, exposure to water vapor, recycling, and long time-on-stream tests. Characterization analyses confirmed the enhanced interactions between Co and doped La, the presence of abundant adsorbed oxygen, and the extensive exposure of Co3+ species in La0.029CoOx-300 nanosheets. Theoretical calculations further revealed that La doping was beneficial for the formation of oxygen vacancies and the adsorption of more hydroxyl groups. These features strongly promoted the adsorption and activation of oxygen, thereby accelerating the benzene oxidation processes. This work underscores the advantages of doping rare-earth elements into transition-metal oxides as a cost-effective yet efficient strategy for purifying industrial exhausts.

Dual chemodynamic/photothermal therapeutic nanoplatform based on DNA-functionalized prussian blue.

The combination of chemodynamic therapy and photothermal therapy has a promising application owing to its impressive anti-cancer effects. However, the degradability of the material and the lack of targeting severely limit its further clinical application. Herein, DNAs containing nucleolin aptamer (AS1411) and different bases sequences were used to functionalize PB NPs for the targeted treatment. Compared to prussian blue, DNA-functionalized prussian blue does not reduce the photothermal properties of prussian blue. Moreover, DNA confers DNA-functionalized prussian blue targeting and higher enzymatic activity, thereby achieving a more effective combination of chemodynamic and photothermal treatment. The therapeutic efficacy of this nanoplatform was evaluated in vivo and in vitro experiments, exhibiting that DNA-functionalized prussian blue nanozyme can maximize the precise control of the therapeutic effect, reduce the toxic and side effects caused by non-specific accumulation on other normal cells, and effectively achieve targeted killing of cancer cells. This work demonstrates that DNA-functionalized prussian blue can improve the efficiency of combined tumor treatment and enhance the application value of prussian blue in tumor treatment, which is expected to provide theoretical support for clinical application.

Cesarean hysterectomy in pregnancies complicated with placenta previa accreta: a retrospective hospital-based study.

BACKGROUND: Placenta previa accreta (PPA) is a severe obstetric condition that can cause massive postpartum hemorrhage and transfusion. Cesarean hysterectomy is necessary in some severe cases of PPA to stop the life-threatening bleeding, but cesarean hysterectomy can be associated with significant surgical blood loss and major complications. The current study is conducted to investigate the potential risk factors of excessive blood loss during cesarean hysterectomy in women with PPA. METHODS: This is a retrospective study including singleton pregnancies after 28 weeks of gestation in women with placenta previa and pathologically confirmed placenta accreta spectrum who received hysterectomy during cesarean sections. A total of 199 women from January 2012 to August 2023 were included in this study and were divided into Group 1 (estimated surgical blood loss (EBL) ≤ 3500 mL, n = 103) and Group 2 (EBL > 3500 mL, n = 96). The primary outcome was defined as an EBL over 3500 mL. Baseline characteristics and surgical outcomes were compared between the two groups. A multivariate logistic regression model was applied to find potential risk factors of the primary outcome. RESULTS: Massive surgical blood loss was prevalent in our study group, with a median EBL of 3500 mL. The multivariate logistic analysis showed that emergency surgery (OR 2.18, 95% CI 1.08-4.41, p = 0.029), cervical invasion of the placenta (OR 2.70, 95% CI 1.43-5.10, p = 0.002), and intraoperative bladder injury (OR 5.18, 95% CI 2.02-13.28, p = 0.001) were all associated with the primary outcome. Bilateral internal iliac arteries balloon occlusion (OR 0.57, 95% CI 0.34-0.97) and abdominal aortic balloon occlusion (OR 0.33, 95% CI 0.19-0.56) were negatively associated with the primary outcome. CONCLUSIONS: Emergency surgery, cervical invasion of the placenta, and intraoperative bladder injury were potential risk factors for additional EBL during cesarean hysterectomy in women with PPA. Future prospective studies are needed to confirm the effect of intra-arterial balloon occlusion in cesarean hysterectomy of PPA.

Perinatal outcomes of selective termination in dichorionic twin pregnancies: a retrospective study from a single center.

OBJECTIVE: Selective termination (ST) is an appropriate procedure for managing discordant fetal anomalies in dichorionic diamniotic (DCDA) twin pregnancies. The aim of this study was to investigate the perinatal outcomes of ST at different gestational ages in DCDA twin pregnancies. METHODS: This retrospective study was conducted on DCDA twin pregnancies with STs at West China Second University Hospital between January 2012 and December 2022. According to the gestational age at which ST was performed, the patients were assigned to four groups: Group 1 (13 to 17 + 6 weeks), Group 2 (18 to 23 + 6 weeks), Group 3 (24 to 27 + 6 weeks), and Group 4 (≥ 28 weeks). RESULTS: We identified 230 patients for this study. The overall rates of miscarriage, preterm delivery at < 32 weeks, and term delivery were 1.3%, 10.5%, and 50%, respectively, while the rates of live birth and neonatal survival were 98.7% and 98.2%, respectively. The rate of term birth was highest (70.6%) and the birth weight was heaviest (2931 ± 535 g) in Group 1 (p = 0.000). In the presence of a fetus subjected to feticide, the mean delivery age was earlier than that in the non-presenting group (p = 0.017); accordingly, the mean birth weight in the feticide group was lower (2366 ± 628 g) than that in the non-presenting group (2590 ± 634 g) (p = 0.011). When we examined the relative relationship between reduction weeks and delivery weeks of twins by correlation analysis, we observed that with regard to maternal prognosis, two pregnancies involved preterm premature rupture of membranes (PPROM) at 7 days and 3 days after the procedure. Intrauterine infection occurred in two patients in Group 4, but there were no maternal deaths or maternal coagulatory abnormalities. CONCLUSIONS: Optimal perinatal outcomes were obtained by ST of DCDA pregnancies before 18 weeks, regardless of whether or not the reduced fetus was the presenting twin. However, if legally possible, late (i.e., after 28 weeks) procedures can be a safe alternative for patients diagnosed after the 18th week of gestation. Overall, we herein noted a negative correlation between the procedure week and the delivery week in this study. Moreover, ST of the non-presenting twin was associated with a heavier birth weight and later gestational age at delivery.

An electrochemical biosensor for sensitive detection of live Salmonella in food via MXene amplified methylene blue signals and electrostatic immobilization of bacteriophages.

A novel bacteriophage-targeted electrochemical biosensor designed for accurate and quantitative detection of live Salmonella in food samples is presented. The biosensor is simply constructed by electrostatic immobilizing bacteriophages on MXene-nanostructured electrodes. MXene, renowned for its high surface area, biocompatibility, and conductivity, serves as an ideal platform for bacteriophage immobilization. This allows for a high-density immobilization of bacteriophage particles, achieving approximately 71 pcs µm-2. Remarkably, the bacteriophages immobilized MXene nanostructured electrodes still maintain their viability and functionality, ensuring their effectiveness in pathogen detection. Therefore, the proposed biosensor exhibited enhanced sensitivity with a low limit of detection (LOD) of 5 CFU mL-1. Notably, the biosensor shows excellent specificity in the presence of other bacteria that commonly contaminate food and can distinguish live Salmonella from a mixed population. Furthermore, it is applicable in detecting live Salmonella in food samples, which highlights its potential in food safety monitoring. This biosensor offers simplicity, convenience, and suitability for resource-limited environments, making it a promising tool for on-site monitoring of foodborne pathogenic bacteria.

Multifunctional Imidazolidinyl Urea Additive Initiated Complex with PbI2 Toward Efficient and Stable Perovskite Solar Cells.

High-quality perovskite absorption layer is the fundamental basis for efficient and stable perovskite solar cells (PSCs). Due to the ionic nature of perovskite components, plentiful charged defects and suspension bonds remain on the surface of perovskite grains after continuous high-temperature annealing. Here, the complex initiated by the introduction of a multifunctional imidazolidinyl urea (IU) additive into the PbI2 precursor solution could serve as nucleation sites and crystallization templates for perovskite crystals to optimize the growth of high-quality perovskite films. By anchoring at the grain boundaries of perovskite films, IU molecules could passivate various types of defects, improve the hydrophobic properties, and inhibit lead leakage. Attributed to reduced defect density, improved charge transport, and inhibited α-FAPbI3 transition, the PSCs prepared based on IU additives achieved a champion power conversion efficiency of 23.18% (21.51% for the control PSCs) with negligible hysteresis and satisfactory stability.

Hydroxyl-Decorated Pt as a Robust Water-Resistant Catalyst for Catalytic Benzene Oxidation.

In catalytic oxidation reactions, the presence of environmental water poses challenges to the performance of Pt catalysts. This study aims to overcome this challenge by introducing hydroxyl groups onto the surface of Pt catalysts using the pyrolysis reduction method. Two silica supports were employed to investigate the impact of hydroxyl groups: SiO2-OH with hydroxyl groups and SiO2-C without hydroxyl groups. Structural characterization confirmed the presence of Pt-Ox, Pt-OHx, and Pt0 species in the Pt/SiO2-OH catalysts, while only Pt-Ox and Pt0 species were observed in the Pt/SiO2-C catalysts. Catalytic performance tests demonstrated the remarkable capacity of the 0.5 wt % Pt/SiO2-OH catalyst, achieving complete conversion of benzene at 160 °C under a high space velocity of 60,000 h-1. Notably, the catalytic oxidation capacity of the Pt/SiO2-OH catalyst remained largely unaffected even in the presence of 10 vol % water vapor. Moreover, the catalyst exhibited exceptional recyclability and stability, maintaining its performance over 16 repeated cycles and a continuous operation time of 70 h. Theoretical calculations revealed that the construction of Pt-OHx sites on the catalyst surface was beneficial for modulating the d-band structure, which in turn enhanced the adsorption and activation of reactants. This finding highlights the efficacy of decorating the Pt surface with hydroxyl groups as an effective strategy for improving the water resistance, catalytic activity, and long-term stability of Pt catalysts.

Thrombospondin 2 is a novel biomarker of essential hypertension and associated with nocturnal Na+ excretion and insulin resistance.

BACKGROUND: Thrombospondins (TSPs) play important roles in several cardiovascular diseases. However, the association between circulating (plasma) thrombospondin 2 (TSP2) and essential hypertension remains unclear. The present study was aimed to investigate the association of circulating TSP2 with blood pressure and nocturnal urine Na+ excretion and evaluate the predictive value of circulating TSP2 in subjects with hypertension. METHODS AND RESULTS: 603 newly diagnosed essential hypertensive subjects and 508 healthy subjects were preliminarily screened, 47 healthy subjects and 40 newly diagnosed essential hypertensive subjects without any chronic diseases were recruited. The results showed that the levels of circulating TSP2 were elevated in essential hypertensive subjects. The levels of TSP2 positively associated with systolic blood pressure (SBP), diastolic blood pressure (DBP), and other clinical parameters, including homeostasis model assessment of insulin resistance (HOMA-IR), brachial-ankle pulse wave velocity, and serum triglycerides, but negatively associated with nocturnal urine Na+ concentration and excretion and high-density lipoprotein cholesterol. Results of multiple linear regressions showed that HOMA-IR and nocturnal Na+ excretion were independent factors related to circulating TSP2. Mantel-Haenszel chi-square test displayed linear relationships between TSP2 and SBP (χ2 = 35.737) and DBP (χ2 = 26.652). The area under receiver operating characteristic curve (AUROC) of hypertension prediction was 0.901. CONCLUSION: Our study suggests for the first time that the circulating levels of TSP2 may be a novel potential biomarker for essential hypertension. The association between TSP2 and blood pressure may be, at least in part, related to the regulation of renal Na+ excretion, insulin resistance, and/or endothelial function.

Comparison of antegrade robotic assisted VS laparoscopic inguinal lymphadenectomy for penile cancer.

BACKGROUND: Minimally invasive modifications of inguinal lymphadenectomy (IL), including laparoscopic IL (LIL) and robotic-assisted IL (RAIL), have been utilized for penile cancer. Comparative study is necessary to guide the decision about which minimally invasive technique to select for IL. Therefore we compared RAIL with LIL performed via an antegrade approach in terms of perioperative outcomes. METHODS: We conducted a retrospective study of 43 patients who underwent RAIL (n = 20) or LIL (n = 23) for penile cancer from 2016 to 2020. The key surgical procedures and techniques are described. Complications were graded by the Clavien-Dindo classification, and operative time, estimated blood loss (EBL), lymph nodal yield, nodal positivity, postoperative drain duration, and disease recurrence during follow-up were assessed. Categorical variables were compared using chi-squared whereas continuous variables were compared by t-tests. RESULTS: The operative time for RAIL was significantly shorter than that of LIL (median 83 vs 95 min). Significantly less blood loss was reported with RAIL than with LIL (median 10 vs 35 ml). Lymph node yield, pathological positive nodes, the hospital stay, postoperative drain duration, postoperative complications and recurrence were similar for RAIL and LIL. CONCLUSIONS: For patients with penile cancer, perioperative outcomes of RAIL and LIL were similar, but there was less blood loss, a shorter operative time for robotic cases.

Maternal and Neonatal Outcomes in Pregnancy Complicated with Pulmonary Hypertension.

Background: Pulmonary hypertension (PH) is a life-threatening disease with significant maternal morbidity and mortality. Methods: To assess pregnancy and neonatal outcomes and determine the risk factors for adverse maternal and neonatal outcomes in women with pulmonary hypertension (PH), a retrospective analysis was carried out examining 71 pregnancies in patients with PH who delivered at a tertiary care center in West China between January 2011 and May 2016. Results: One pregnancy resulted in spontaneous abortion and six resulted in terminated abortions. Cardiac complications were encountered in 16.9% including three maternal mortalities. At least one pregnancy complication occurred in 28.2% of all the pregnancies. Diagnosis after the third trimester, severe PH and/or right ventricular systolic dysfunction were predictive of adverse fetal/neonatal events. A history of prior cardiac events and right ventricular systolic dysfunction and/or baseline New York Heart Association (NYHA) class III or IV were the main predictive factors of adverse maternal cardiac events. Conclusions: In our study, we found that PH poses high risks for maternal and fetal morbidity and mortality. A detailed pre-pregnancy baseline assessment is strongly recommended in women with PH to identify those with the highest risk and subsequently guide clinical management.

Comparison of transvaginal cervical cerclage versus laparoscopic abdominal cervical cerclage in cervical insufficiency: a retrospective study from a single centre.

BACKGROUND: Cervical cerclage has been proposed as an effective treatment for cervical insufficiency, but there has been controversy regarding the surgical options of cervical cerclage in singleton and twin pregnancies. This study aimed to compare the pregnancy outcomes between transvaginal cervical cerclage (TVC) and laparoscopic abdominal cervical cerclage (LAC) in patients with cervical insufficiency. We also aimed to evaluate the efficacy and safety, and provide more evidence to support the application of cervical cerclage in twin pregnancies. METHODS: A retrospective study was carried out from January 2015 to December 2021. The primary outcomes were the incidence of spontaneous preterm birth (sPTB) < 24 weeks, < 28, < 32, < 34 weeks, and < 37weeks, gestational age at delivery, and the incidence of admission for threatened abortion or preterm birth after cervical cerclage. The secondary outcomes included admission to the Neonatal Intensive Care Unit, adverse neonatal outcomes and neonatal death. We also analysed the pregnancy outcomes of twin pregnancies after cervical cerclage. RESULTS: A total of 289 patients were identified as eligible for inclusion. The LAC group (n = 56) had a very low incidence of sPTB ˂ 34 weeks, and it was associated with a significant decrease in sPTB < 28 weeks, ˂32 weeks, ˂34 and < 37 weeks, and admission to the hospital during pregnancy for threatened abortion or preterm birth after cervical cerclage (0 vs.27%; 1.8% vs. 40.3%; 7.1% vs. 46.8%; 14% vs. 63.5%, 8.9% vs. 62.2%, respectively; P < 0.001), and high in gestational age at delivery compared with the TVC group (n = 233) (38.3 weeks vs.34.4 weeks,P < 0.001). Neonatal outcomes in the LAC group were significantly better than those in the TVC group. The mean gestational age at delivery was 34.3 ± 1.8 weeks, with a total foetal survival rate of 100% without serious neonatal complications in twin pregnancies with LAC. CONCLUSION: In patients with cervical insufficiency, LAC appears to have better pregnancy outcomes than TVC. For some patients, LAC is a recommended option and may be selected as the first choice. Even in twin pregnancies, cervical cerclage can improve pregnancy outcomes with a longer latency period, especially in the LAC group.

Perinatal outcomes associated with ICP in twin pregnancies were worse than singletons: an almost 5-year retrospective cohort study.

BACKGROUND: Intrahepatic cholestasis of pregnancy (ICP) is associated with an increased risk of adverse perinatal outcomes leading to high perinatal morbidity and mortality. However, few studies have examined twin pregnancies complicated by ICP. To assess the perinatal outcomes of twin pregnancies with ICP, a retrospective cohort study was conducted. METHODS: A total of 633 twin pregnancies and 1267 singleton pregnancies with ICP were included. In addition, a correlation study was performed on the matched total bile acid (TBA) levels from maternal serum, fetal umbilical venous blood, and amniotic fluid of 33 twin pregnancies from twin groups. RESULTS: When compared to singletons, twin pregnancies with ICP had a higher risk of cesarean section (CS) (96.4% vs. 76.1%), preterm birth (PTB) (82.6% vs. 19.7%), fetal distress (2.0% vs. 1.3%), and neonatal intensive care unit (NICU) admission (23.6% vs. 5.1%), which was significantly related to increasing TBA levels (P < 0.05). In twin pregnancies with TBA ≥100 µmol/L, the incidences of CS, PTB, fetal distress, neonatal asphyxia, and meconium-stained amniotic fluid were 94.4, 100, 11.1, 5.6, and 36.1%, respectively. Furthermore, the maximum maternal TBA levels were positively correlated with TBA levels in the amniotic fluid (r = 0.61, P < 0.05) and umbilical cord blood (r = 0.44, P < 0.05), and a similar correlation was found for maternal TBA levels at delivery. TBA levels in umbilical cord blood and amniotic fluid also had a significant and positive correlation (r = 0.52, P < 0.05). CONCLUSIONS: Twin pregnancies with ICP had a higher risk for adverse perinatal outcomes than singletons, which was associated with higher TBA levels. TBA can be transported through the placenta and is involved in uterus-placenta-fetal circulation.

Conjoined twins in dichorionic diamniotic triplet pregnancy: a report of three cases and literature review.

BACKGROUND: Conjoined twins are a rare and serious complication of monochorionic twins. The total incidence is 1.5 per 100,000 births, and about 50% are liveborn. Prenatal screening and diagnosis of conjoined twins is usually performed by ultrasonography. Magnetic resonance imaging can be used to assist in the diagnosis if necessary. Conjoined twins in dichorionic diamniotic triplet pregnancy are extremely rare. CASE PRESENTATION: We reported three cases of dichorionic diamniotic triplet pregnancy with conjoined twins. Due to the poor prognosis of conjoined twins evaluated by multidisciplinary teams, selective termination of conjoined twins was performed in three cases. In case 1, selective reduction of the conjoined twins was performed at 16 gestational weeks, and a healthy female baby weighing 3270 g was delivered at 37 weeks. In case 2, the conjoined twins were selectively terminated at 17 weeks of gestation, and a healthy female baby weighing 2760 g was delivered at 37 weeks and 4 days. In case 3, the conjoined twins were selectively terminated at 15 weeks and 2 days, and a healthy female baby weighing 2450 g was delivered at 33 weeks and 6 days. The babies of all three cases were followed up and are in good health. CONCLUSION(S): Surgical separation is the only treatment for conjoined twins after birth. Early determination of chorionicity and antenatal diagnosis of conjoined twins in triplet gestations are critical for individualized management options and the prognosis of normal triplets. Expecting parents should be extensively counseled by multidisciplinary teams. If there are limitations in successful separation after birth, early selective termination of the conjoined twins by intrathoracic injection of potassium chloride may be a procedure in dichorionic diamniotic triplet pregnancy to improve perinatal outcomes of the normal triplet.

An electrochemical aptasensor for amyloid-ß oligomer based on double-stranded DNA as "conductive spring".

In order to overcome the antibody-based sensor's shortcomings, an electrochemical aptamer (Apt)-based sensor was developed for amyloid-ß40 oligomer (Aß40-O). The aptasensor was constructed by locating Apt and ferrocence (Fc) on streptavidin-modified gold (SA-gold) nanoparticles. The obtained AptFc@SA-gold nanoparticles were linked onto the Au electrode via the connection of double-stranded DNA (dsDNA) as a "conductive spring." The determination of Aß40-O was performed with square-wave voltammetry (SWV). Upon bio-recognition between Apt and Aß40-O, the conformation of Apt changed and the formed Apt/Aß40-O complex separated from the SA-gold surface. As a result, the surface charge of SA-gold positively shifted, weakening the electrostatic attraction between the SA-gold and the positively charged Au electrode surface (at potential range of 0.1~0.5 V, corresponding to the Fc redox transformation), and stretching the dsDNA chain. Based on the exponential decay of dsDNA's electron transfer efficiency on its chain stretching, the oxidation current density from Fc decreased and displayed linear correlation to the concentration of Aß40-O. A wide linear range of 0.100 nM to 1.00 µM with a low detection limit of 93.0 pM was obtained. The aptasensor displayed excellent selectivity toward Aß40-O in contrast to other possible interfering analogs (Aß40 monomer, Aß42 monomer, and oligomer) at × 100 higher concentrations. The recoveries for Aß40-O-spiked artificial cerebrospinal fluid and healthy human serum were 94.0~104% and 92.8~95.4%, respectively. The electrochemical aptasensor meets the demands of clinic determination of Aß40-O, which is significant for the early diagnosis of AD. Graphical abstract Schematic representation of the electrochemical aptasensor for amyloid-ß oligomer based on the surface charge change induced by target binding.

Coimmunocapture and Electrochemical Quantitation of Total and Phosphorylated Amyloid-ß40 Monomers.

Phosphorylated proteins play important roles in the pathogenesis of Alzheimer's disease (AD). The most abundant constituent in AD's brain deposit is the amyloid-ß40 peptide (Aß40). Based on it, the degree of phosphorylated Aß40 in body fluids (e.g., cerebrospinal fluid, CSF), which is defined by the ratio of phosphorylated Aß40 to total Aß40 (pAß40/tAß40), is anticipated to be an index for early diagnosis of AD. The major challenge in pAß40/tAß40 detection is the large concentration difference between two Aß40 forms in the real samples, which usually requires multichannel equipment and complicated detection process. In this paper, we revealed the unexpected close affinities of the anti-Aß40 antibody to Aß40 (40.2 nM-1) and to pAß40 (42.3 nM-1). Based on it, a convenient coimmunocapture and electrochemical quantitation of tAß40 and pAß40 was achieved on an anti-Aß40 antibody immobilized Au electrode (anti-Aß40/Au). Once Aß40 and pAß40 were synchronously captured on the anti-Aß40/Au electrode, the tAß40 levels in CSF samples were quantified with electrochemical impedance spectroscopy. With the signal amplification from Cd2+/Ti4+-functionalized titanium phosphate nanospheres (Cd2+/Ti4+@TiP) which was selective conjugated to pAß40, concentrations of low abundant pAß40 as low as 1 fM were readily measured by square wave voltammetry. Our results reveal that despite the concentrations of tAß40 and pAß40 fluctuate in each individual case, the concentration ratios of pAß40/tAß40 in CSF samples from AD patients are significant larger than those from healthy donors. It demonstrates that the degree of phosphorylated Aß40 is hopeful to be an effective index for evaluating the AD progress and improving the accuracy of clinic AD diagnosis.

An electrochemical dual-signaling aptasensor for the ultrasensitive detection of insulin.

Insulin plays a central role in physiological glycolmetabolism and is associated with diabetes and related diseases. In this work, a dual-signaling electrochemical aptasensor for insulin detection with high sensitivity and specificity has been reported. Methylene blue (MB)-modified insulin-binding aptamer (IBA) as "signal-off" probe, and (DNA2)/Ferrocene (Fc) co-modified gold nanoparticles (DNA2Fc@GNPs) as the "signal-on" probe were integrated with linker mDNA to fabricate the DNA2Fc@GNPs/mDNA/MB-IBA modified Au electrode as the sensing interface, and the current responses of MB and Fc were used as signal indicators. As expected, the incubation of insulin with DNA2Fc@GNPs/mDNA/MB-IBA/Au electrode resulted in the current responses of MB and Fc decreased and increased, respectively. Based on this strategy, the detection of insulin was successfully achieved, and a linear range from 10 pM to 10 nM with the detectable lowest concentration of 0.1 pM was obtained. By measuring the insulin concentrations in serum samples, this proposed aptasensor has been proven to be of high specificity and accuracy. Moreover, the dual-signaling is useful for the more accurate and reproducible detection through their self-referencing capability. This aptasensor possesses such advantages as simplicity, rapid responses, high sensitivity, specificity and accuracy, which is significant for improving the diagnosis of insulin-related diseases.

An experimental study of the impacts of solar radiation and temperature on mercury emission from different natural soils across China.

Mercury (Hg) emission from natural soil is one of the most important contributors to global Hg cycles. Research on Hg emission from soil to air has been carried out in China. Currently, most of the research focuses on contaminated sites in China, while research in other regions is rare. To provide more accurate information on Hg emissions from soil to air in China and obtain additional laboratory data to verify the role of solar radiation and temperature in this process, we sampled and measured Hg emission fluxes from various natural soils (range, 48-240 ng/g) across mainland China under different solar radiation (0-900 W·m-2) and temperature (15-45 °C) conditions in a laboratory. We found that in different places in China, Hg emissions from natural soils occurred more easily when the soil Hg concentration, temperature, and solar radiation were high, but the impacts were different among the regions due to different soil types. Hg emissions from natural soils (0.071-24 ng·m2·h-1) were typically lower than those from contaminated sites, suggesting that additional measurements in natural soils are desirable. The results of this study could provide more accurate information on Hg emission from natural soil to air and help establish a nationwide natural soil Hg emission inventory in China.