Superior Interfacial Contact Yields Efficient Electron Transfer Rate and Enhanced Solar Photocatalytic Hydrogen Generation in M/C3N4 Schottky Junctions.

Various literature studies (Table 6) have reported that dispersion of metal nanoparticles (NPs) on graphitic carbon nitride g-C3N4 (M/CN) has considerably improved the photocatalytic hydrogen yield. It is understood that metal NPs create active sites on the surface of CN and act as a cocatalyst. However, the precise changes induced by different metal NPs on the surface of CN still elude us. Here, we report a thorough understanding and comparison of the morphology, metal-support interactions, interfacial charge transfer kinetics, and band characteristics in different M/CN (M = Pt, Pd, Au, Ag, Cu) correlated with photocatalytic activity. Among all metals, Pt/CN was found to be the best performer both under sunlight and UV-visible irradiation. Under sunlight, maximum H2@ 2.7 mmol/h/g was observed over Pt/CN followed by Pd/CN > Au/CN > Ag/CN > Cu/CN ≈ CN. The present study revealed that among all metals, Pt formed superior interfacial contact with g-C3N4 as compared to other metals. The maximum Schottky barrier height (Φb,Pt) of 0.66 V was observed at Pt/CN followed by Φb,Au/CN (0.46 V) and Φb,Pd/CN (0.05 V). The presence of electron-deficient Pt in Pt-XPS, decrease in the intensity of d-DOS of Pt near the Fermi level in VB-XPS, increase in CB tail states, and cathodic shift in Vfb in MS plots sufficiently confirmed strong metal-support interactions in Pt/CN. Due to the SPR effect, Au and Ag NPs suffered from agglomeration and poor dispersion during photodeposition. Finely dispersed Pt NPs (2-4 nm, 53% dispersion) successfully competed with shallow/deep trap states and drove the photogenerated electrons to active metallic sites in a drastically reduced time period as investigated by femtosecond transient absorption spectroscopy. Typically, an interfacial electron transfer rate, KIET,avg, of 2.5 × 1010 s-1 was observed for Pt/CN, while 0.087 × 1010 s-1 was observed in Au/CN. Band alignment/potentials at M/CN Schottky junctions were derived and most favorable in Pt/CN with CB tail states much above the water reduction potential; however, in the case of Pd, these extend much below the H+/H2 potential and hence behave like deep trap states. Thus, in Pd/CN (τ0 = 4200 ps, 49%) and Ag/CN (3870 ps, 53%), electron deep trapping dominates over charge transfer to active sites. The present study will help in designing futuristic new cocatalyst-photocatalyst systems.

Safety and Feasibility of Skin-to-Skin Contact in the Delivery Room for High-Risk Cardiac Neonates.

Early skin-to-skin contact (SSC), beginning in the delivery room, provides myriad health benefits for mother and baby. Early SSC in the delivery room is the standard of care for healthy neonates following both vaginal and cesarean delivery. However, there is little published evidence on the safety of this practice in infants with congenital anomalies requiring immediate postnatal evaluation, including critical congenital heart disease (CCHD). Currently, the standard practice following delivery of infants with CCHD in many delivery centers has been immediate separation of mother and baby for neonatal stabilization and transfer to a different hospital unit or a different hospital altogether. However, most neonates with prenatally diagnosed congenital heart disease, even those with ductal-dependent lesions, are clinically stable in the immediate newborn period. Therefore, we sought to increase the percentage of newborns with prenatally diagnosed CCHD who are born in our regional level II-III delivery hospitals who receive mother-baby SSC in the delivery room. Using quality improvement methodology, through a series of Plan-Do-Study-Act cycles we successfully increased mother-baby skin-to-skin contact in the delivery room for eligible cardiac patients born across our city-wide delivery hospitals from a baseline 15% to greater than 50%.

An Evolutionarily Conserved Helix Mediates Ameloblastin-Cell Interaction.

Ameloblastin (Ambn) has the potential to regulate cell-matrix adhesion through familiar cell-binding domains, but the proposed sequence motifs are not highly conserved across species. Here, we report that Ambn binds to ameloblast-like cell membranes through a highly evolutionary conserved amphipathic helix-forming (AH) motif encoded by exon 5. We applied high-resolution confocal microscopy to show colocalization of Ambn with ameloblast membrane surfaces in developing mouse incisors. Using a series of Ambn-derived peptides and Ambn variants, we showed that Ambn binds to cell membranes through a motif within the sequence encoded by exon 5. Using peptides derived from the N- or C-termini of this sequence, as well as Ambn variants that lacked or had a disrupted AH motif, we demonstrated that the AH motif located at the N-terminus of the sequence is involved in cell-Ambn adhesion. Sequence analysis revealed that this highly conserved AH motif is absent from other enamel matrix proteins, including amelogenin, enamelin, and amelotin. Collectively, these data suggest that Ambn binds to the cell surface membrane via a helix-forming motif and provide insight into the molecular mechanism and function of Ambn in enamel cell-matrix interaction.

Effects of practice change on outcomes of extremely preterm infants with patent ductus arteriosus.

AIM: To determine whether a decrease in patent ductus arteriosus (PDA) treatment or ligation in extremely preterm (EP) infants was associated with changes in rates of mortality and/or morbidities. METHODS: Observational study on EP infants admitted from 2008 to 2015. The small baby guidelines do not mandate ligation, however, in late 2010 the guidelines were amended based on new literature suggested that ligation may increase rates of morbidities. RESULTS: There were 717 EP infants admitted during the study period. There were no significant changes in gestational age, birthweight or annual admissions during the study period. The annual rate of PDA medical treatment declined significantly (R = 0.83, p = 0.01), while the annual rate of PDA ligation declined substantially (R = 0.88, p = 0.004). The annual mortality rate also declined significantly (R = 0.81, p = 0.014). The annual rates of bronchopulmonary dysplasia (BPD), necrotising enterocolitis and intraventricular haemorrhage did not change significantly. CONCLUSION: In this cohort of EP patients, the rate of PDA ligation decreased substantially since 2010, with no apparent adverse effects on mortality or rates of BPD. These data are consistent with the concept that ligation does not improve outcomes in EP infants.

Insight into growth of Au-Pt bimetallic nanoparticles: an in situ XAS study.

Au-Pt bimetallic nanoparticles have been synthesized through a one-pot synthesis route from their respective chloride precursors using block copolymer as a stabilizer. Growth of the nanoparticles has been studied by simultaneous in situ measurement of X-ray absorption spectroscopy (XAS) and UV-Vis spectroscopy at the energy-dispersive EXAFS beamline (BL-08) at Indus-2 SRS at RRCAT, Indore, India. In situ XAS spectra, comprising both X-ray near-edge structure (XANES) and extended X-ray absorption fine-structure (EXAFS) parts, have been measured simultaneously at the Au and Pt L3-edges. While the XANES spectra of the precursors provide real-time information on the reduction process, the EXAFS spectra reveal the structure of the clusters formed in the intermediate stages of growth. This insight into the formation process throws light on how the difference in the reduction potential of the two precursors could be used to obtain the core-shell-type configuration of a bimetallic alloy in a one-pot synthesis method. The core-shell-type structure of the nanoparticles has also been confirmed by ex situ energy-dispersive spectroscopy line-scan and X-ray photoelectron spectroscopy measurements with in situ ion etching on fully formed nanoparticles.

Outcomes following indomethacin prophylaxis in extremely preterm infants in an all-referral NICU.

OBJECTIVE: We examined data from a contemporary cohort of extreme prematurity (EP) infants admitted to an all-referral Children's Hospital neonatal intensive care unit (NICU) to determine whether prophylactic indomethacin (PI) may continue to benefit these patients. STUDY DESIGN: An observational study utilizing the small baby ICU data registry that was queried for all EP infants admitted between 2005 and 2014 with documentation of PI use (671 total EP infants; 141 (21%) did not receive PI (control); 530 (79%) received PI (PI). This cohort of EP infants was born at outside hospitals and transferred to our level IV NICU with a mean age on admission of 13 days, well after the PI would have been administered. RESULTS: No difference existed between the control and PI groups in gestational age, birth weight, severity of illness, other in-hospital outcomes or developmental delay. PI infants had a significantly lower mortality rate (P=0.0004), lower relative risk (RR) for mortality 0.52 (95% confidence interval (CI) 0.37 to 0.73, P=0.0001) and lower RR of developing the combined outcome of death or bronchopulmonary dysplasia (RR 0.91, 95% CI 0.85 to 0.98, P=0.012) when compared with the control group. Notably, there was no significant effect of PI on incidence of severe intraventricular hemorrhage or patent ductus arteriosus ligation. CONCLUSION: PI administration was associated with improved survival in EP infants referred to a level IV Children's Hospital NICU.

Challenges, successes and opportunities for reducing readmissions in a referral-based children's hospital NICU.

AIM: To evaluate readmission data in a level IV neonatal intensive care unit (NICU) to identify patient characteristics and process failures which serve as drivers for readmission. METHODS: Our center is a primary referral center in Central and Southeast Ohio, providing us a unique opportunity to evaluate readmissions. We studied our current discharge process, caregiver perception of discharge readiness, parental comfort and the pre-discharge and post-discharge characteristics of infants. RESULTS: Our readmission rate during the 4 year period has remained stable at 9.8%. 74% of the caregivers rated that their perception of their baby's medical readiness for discharge was good to excellent. Duration of hospitalization and public insurance coverage (Medicaid) were significant risk factors for readmission (p = 0.00). In our setting, the majority of the patients are readmitted through the emergency department and nearly half of all readmissions were for 3 or fewer days. Patients discharged from our Comprehensive Center for BPD had similar readmission rate despite characteristics which should increase their readmission rate. CONCLUSIONS: Readmission rate is a poor indicator of the quality of care provided in the NICU. In addition to patient factors such as longer length of stay and Medicaid, our data suggests that preventing readmission depends on having systems in place to help families cope with transition of care after discharge.

Amelogenin-Ameloblastin Spatial Interaction around Maturing Enamel Rods.

Amelogenin and ameloblastin are 2 extracellular matrix proteins that are essential for the proper development of enamel. We recently reported that amelogenin and ameloblastin colocalized during the secretory stage of enamel formation when nucleation of enamel crystallites occurs. Direct interactions between the 2 proteins have been also demonstrated in our in vitro studies. Here, we explore interactions between their fragments during enamel maturation. We applied in vivo immunofluorescence imaging, quantitative co-localization analysis, and a new FRET (fluorescence resonance energy transfer) technique to demonstrate ameloblastin and amelogenin interaction in the maturing mouse enamel. Using immunochemical analysis of protein samples extracted from 8-d-old (P8) first molars from mice as a model for maturation-stage enamel, we identified the ~17-kDa ameloblastin (Ambn-N) and the TRAP (tyrosine-rich amelogenin peptide) fragments. We used Ambn-N18 and Ambn-M300 antibodies raised against the N-terminal and C-terminal segments of ameloblastin, as well as Amel-FL and Amel-C19 antibodies against full-length recombinant mouse amelogenin (rM179) and C-terminal amelogenin, respectively. In transverse sections, co-localization images of N-terminal fragments of amelogenin and ameloblastin around the prism boundary revealed the "fish net" pattern of the enamel matrix. Using in vivo FRET microscopy, we further demonstrated spatial interactions between amelogenin and ameloblastin N-terminal fragments. In the maturing mouse enamel, the association of these residual protein fragments created a discontinuity between enamel rods, which we suggest is important for support and maintenance of enamel rods and eventual contribution to unique enamel mechanical properties. We present data that support cooperative functions of enamel matrix proteins in mediating the structural hierarchy of enamel and that contribute to our efforts to design and develop enamel biomimetic material.

Efficacy of anti-scorpion venom serum over prazosin in the management of severe scorpion envenomation.

BACKGROUND: Scorpion venoms cause a massive release of neurotransmitters. Either anti-scorpion venom serum (AScVS) or prazosin has been used in the management of severe scorpion envenomation. AIMS: To compare the time taken for clinical recovery by patients with severe scorpion envenomation after AScVS therapy with that following prazosin therapy. SETTINGS AND DESIGN: A prospective, open-labeled clinical trial was undertaken to compare the effects of the AScVS and/or prazosin on clinical recovery in scorpion-stung patients. MATERIALS AND METHODS: Eighty-one patients from rural districts of Maharashtra presenting with severe scorpion envenomation were assigned to three treatment groups (AScVS: n = 28; prazosin: n = 25; AScVS + prazosin: n = 28). Severity of scorpion envenomation was graded using a proposed composite clinical scoring system to assess the therapeutic efficacy. AScVS was administered as an intravenous slow bolus, ranging from 40 to 100 ml, depending on the severity of envenomation. Prazosin was given as 1 mg every 3 h. STATISTICAL ANALYSIS USED: The non-parametric "Kruskal-Wallis" test was used in the statistical analysis and a P-value of 0.05 was considered significant. RESULTS: Mean composite scores of patients from the three groups at the time of admission were comparable. Complete clinical recovery was noted in 4.14 ± 1.6 h and 19.28 ± 5.03 h in the subjects who were administered AScVS and prazosin, respectively (P < 0.001). There was no incidence of anaphylactic reaction to AScVS. CONCLUSIONS: Intravenous slow bolus of AScVS given based on the clinical severity of envenomation leads to early recovery than prazosin alone and is well tolerated.

Influence of timing on performance of laparoscopic cholecystectomy for acute biliary pancreatitis.

AIM: Gallstone disease is the most common cause of acute pancreatitis. Cholecystectomy is mandatory to avoid recurrence of pancreatitis. Our objective was to evaluate the results of laparoscopic cholecystectomy (LC) in patients with gall-stone induced pancreatitis. METHODS: All patients presenting to us within the time frame from February 2004 to June 2008 with acute biliary pancreatitis were included in the study. The severity of pancreatitis was assessed by Ranson's criteria. ERCP and endoscopic sphincterotomy was performed when the common bile duct (CBD) was dilated (>6 mm) with either calculi or sludge as seen on imaging. Patients with successful ERCP with predicted demanding laparoscopic cholecystectomy were discharged instead for an elective LC, 4-6 weeks later. Patients with mild pancreatitis (with Ranson's score of 3 or less) and predicted uncomplicated LC underwent surgery at the same admission. The difficulty of the procedure was determined by the presence of adhesions in the gallbladder area, dissection in Calot's triangle, tackling the dilated cystic duct, intra-operative bleeding, and the need for a drain. RESULTS: A total of 26 patients (12 male and 14 female; age range 23-75 years) with acute biliary pancreatitis comprised the study group. Eleven patients with suspected choledocholithiasis underwent ERCP and clearance of the CBD was done in all of them. Nine patients (2 ERCP and 7 non-ERCP) underwent early LC in the same admission. Seventeen patients (9 ERCP and 8 non-ERCP) were predicted as difficult cases for LC and underwent delayed LC. No patient had recurrent pancreatitis in the interval period. CONCLUSION: There was no significant difference in the operative difficulty between early and delayed LC when patients were selected for timing of LC based on pre-defined criteria.

Magnetic behavior of nanocrystalline ErCo(2).

We have investigated the magnetic behavior of the nanocrystalline form of a well-known Laves phase compound, ErCo(2)-the bulk form of which has been known to undergo an interesting first-order ferrimagnetic ordering near 32 K-synthesized by high-energy ball-milling. It is found that, in these nanocrystallites, Co exhibits ferromagnetic order at room temperature, as inferred from the magnetization data. However, the magnetic transition temperature for the Er sub-lattice remains essentially unaffected suggesting the (Er)4f-Co(3d) coupling is weak on Er magnetism. The net magnetic moment as measured at high fields, for example at 120 kOe, is significantly reduced with respect to that for the bulk in the ferrimagnetically ordered state and possible reasons are outlined for this. We have also compared the magnetocaloric behavior for the bulk and for nanoparticles.

Varied presentations of gastrointestinal stromal tumour.

Gastrointestinal stromal tumours (GIST) are soft tissue tumours arising from the mesenchyma in the gastrointestinal tract. These are rare tumours. However, over the past few years with the better understanding of the pathogenesis of GIST and better imaging facilities, the diagnosis is made more frequently. The characteristic diagnostic feature of GIST is the expression of CD34 and receptor tyrosine kinase KIT, CD117 by these tumours. The use of tyrosine kinase inhibitor imatinib mesylate has led to improved outcome. The presentation of GIST however remains non-specific, and varies depending upon the size and the organ of origin. We present a series of four cases of GIST with varied presentation.

Spectrum and outcome of pancreatic trauma.

BACKGROUND AND AIMS: Pancreatic trauma is associated with high morbidity and mortality. Diagnosis is often difficult and surgery poses a formidable challenge. METHOD: Data from 17 patients of pancreatic trauma gathered from a prospectively maintained database were analysed and the following parameters were considered: mode of injury, diagnostic modalities, associated injury, grade of pancreatic trauma and management. Pancreatic trauma was graded from I through IV, as per Modified Lucas Classification. RESULTS: The median age was 39 years (range 19-61). The aetiology of pancreatic trauma was blunt abdominal trauma in 14 patients and penetrating injury in 3. Associated bowel injury was present in 4 cases (3 penetrating injury and 1 blunt trauma) and 1 case had associated vascular injury. 5 patients had grade I, 3 had grade II, 7 had grade III and 2 had grade IV pancreatic trauma. Contrast enhanced computed tomography scan was used to diagnose pancreatic trauma in all patients with blunt abdominal injury. Immediate diagnosis could be reached in only 4 (28.5%) patients. 7 patients responded to conservative treatment. Of the 10 patients who underwent surgery, 6 required it for the pancreas and the duodenum. (distal pancreatectomy with splenectomy-3, pylorus preserving pancreatoduodenectomy-1, debridement with external drainage-1, associated injuries-duodenum-1). Pancreatic fistula, recurrent pancreatitis and pseudocyst formation were seen in 3 (17.05%), 2 (11.7%) and 1 (5.4%) patient respectively. Death occurred in 4 cases (23.5%), 2 each in grades III and IV pancreatic trauma. CONCLUSIONS: Contrast enhanced computed tomography scan is a useful modality for diagnosing, grading and following up patients with pancreatic trauma. Although a majority of cases with pancreatic trauma respond to conservative treatment, patients with penetrating trauma, and associated bowel injury and higher grade pancreatic trauma require surgical intervention and are also associated with higher morbidity and mortality.

Brain abscess following esophageal dilatation.

The authors report a case of brain abscess following esophageal dilatation for corrosive stricture in a 23-year-old woman. High fever and neurological findings post dilatation led us to suspect this rare complication, which was confirmed by cranial computed tomography. Prompt treatment with antibiotics and surgical drainage led to a favorable clinical outcome. This serious complication should be kept in mind when long-term treatment of corrosive stricture by repeated esophageal dilatation is planned. Prior cases of brain abscess following esophageal dilatation are reviewed.