Fabricating BiOCl/BiVO4 nanosheets wrapped in a graphene oxide heterojunction composite for detection of an antihistamine in biological samples.

Antibiotics are essential medications for human and animal health, as they are used to battle urinary infections and bacterial diseases. Therefore, the rapid determination of antibiotic drugs in biological samples is necessary to address the current clinical challenge. Here, we developed a heterojunction ternary composite of BiOCl/BiVO4 nanosheets enriched with graphene oxide (BiOCl/BiVO4@GO) for accurate and minimal-level detection of an antihistamine (promethazine hydrochloride, PMZ) in urine samples. The BiOCl/BiVO4 nanosheets were prepared by a wet chemical approach using a deep eutectic green solvent. The spectroscopic and analytical methods verified the formation and interaction of the BiOCl/BiVO4@GO composite. Our results showed that the thoroughly exfoliated BiOCl/BiVO4@GO composite retained good electrical conductivity and fast charge transfer toward the electrode-electrolyte interface in neutral aqueous media. In addition, the experimental conditions were accurately optimized, and the BiOCl/BiVO4@GO composite showed excellent electrocatalytic activity toward the oxidation of PMZ. Indeed, the BiOCl/BiVO4@GO composite demonstrated a good linear response range (0.01-124.7 µM) and a detection level of 3.3 nM with a sensitivity of 1.586 µA µM-1 cm-2. In addition, the BiOCl/BiVO4@GO composite had excellent storage stability, good reproducibility, and reliable selectivity. Finally, the BiOCl/BiVO4@GO displayed a desirable recovery level of PMZ in urine samples for real-time monitoring.

An Ultrasensitive Detection Platform for Mercury Ions Speciation in Water Using Procaine Hydrochloride Ion Pair Coupled Extractive Spectrofluorimetry.

A simple extractive spectrofluorimetric strategy for trace determination of mercury(II) ions in water employing procaine hydrochloride (PQ+) as an ion pairing fluorescent tagging reagent has been established. The method was based upon the extraction of PQ+ from aqueous iodide media onto dichloromethane as a ternary complex ion associate [(PQ+)2.(HgI4)2-] at pH 9.0-10.0 with subsequent quenching at λex/em = 268/333 nm. The developed strategy exhibited a linear range 20-140 nM with a lower limit of detection (LOD) 6.1 nM, respectively. Intra and inter-day laboratory accuracy and precision for trace analysis of mercury(II) ions in water were performed. Complexed mercury(II) species in real water samples were evaluated along with chemical speciation and successful comparison with most of the reported methods. The method was validated by standard inductively coupled plasma-optical emission spectrometry (ICP-OES) method in terms of student's t- and F tests at 95% confidence interval. The method offers rapidity, selectivity, cost-effectiveness, robustness, and ruggedness. Graphical Abstract Schematic illustration of the proposed sensing mechanism for mercury(II).

Molecular Characterization, Bioinformatic Analysis, and Expression Profile of Lin-28 Gene and Its Protein from Arabian Camel (Camelus dromedarius).

Lin-28 is an RNA-binding protein that is known for its role in promoting the pluripotency of stem cells. In the present study, Arabian camel Lin-28 (cLin-28) cDNA was identified and analyzed. Full length cLin-28 mRNA was obtained using the reverse transcription polymerase chain reaction (RT-PCR). It was shown to be 715 bp in length, and the open reading frame (ORF) encoded 205 amino acids. The molecular weight and theoretical isoelectric point (pI) of the cLin-28 protein were predicted to be 22.389 kDa and 8.50, respectively. Results from the bioinformatics analysis revealed that cLin-28 has two main domains: an N-terminal cold-shock domain (CSD) and a C-terminal pair of retroviral-type Cysteine3Histidine (CCHC) zinc fingers. Sequence similarity and phylogenetic analysis showed that the cLin-28 protein is grouped together Camelus bactrianus and Bos taurus. Quantitative real-time PCR (qPCR) analysis showed that cLin-28 mRNA is highly expressed in the lung, heart, liver, and esophageal tissues. Peptide mass fingerprint-mass spectrometry (PMF-MS) analysis of the purified cLin-28 protein confirmed the identity of this protein. Comparing the modeled 3D structure of cLin-28 protein with the available protein 3D structure of the human Lin-28 protein confirmed the presence of CSD and retroviral-type CCHC zinc fingers, and high similarities were noted between the two structures by using super secondary structure prediction.

Propofol and survival: a meta-analysis of randomized clinical trials.

BACKGROUND: One of the most commonly used hypnotics is propofol. Several studies performed in cardiac surgery suggested an increased mortality in patients receiving a propofol-based total intravenous anaesthesia. Furthermore, the possibility of infections and the 'propofol syndrome' have suggested that propofol might be dangerous. Nonetheless, propofol is widely used in different settings because of its characteristics: fast induction, rapid elimination, short duration of action, smooth recovery from anaesthesia, few adverse effects, no teratogenic effects, characteristics that have undoubtedly contributed to its popularity. The effect of propofol on survival is unknown. We decided to carry out a meta-analysis of all randomized controlled studies ever performed on propofol vs. any comparator in any clinical setting. METHODS: Pertinent studies were independently searched in BioMedCentral, PubMed, Embase, Clinicaltrial.gov, and Cochrane Central Register of Clinical Trials by expert investigators. The following inclusion criteria were used: random allocation to treatment, comparison between propofol and any comparator in any clinical setting. RESULTS: One hundred thirty-three studies randomizing 14,516 patients were included. No differences in mortality between patients receiving propofol [349/6957 (5.0%)] vs. any comparator [340/7559 (4.5%)] were observed in the overall population [risk ratio = 1.05, 95% confidence interval (0.93 to 1.18), P = 0.5] and in several sub-analyses. CONCLUSION: Inspite of theoretical concerns, propofol has no detrimental effect on survival according to the largest meta-analysis of randomized trials ever performed on hypnotic drug.

Frequency of glutathione-S-transferase null-M1 and null-T1 genotypes among the Turabah population in Saudi Arabia.

Glutathione-S-transferases (GST) are key phase II detoxifying enzymes that play critical roles in protection against products of oxidative stress and against electrophiles. Glutathione S-transferase mu (GST-M1) and theta (GST-T1) are isoforms of glutathione transferase enzymes that participate in the metabolism of a wide range of chemicals. Deletion variants that are associated with a lack of enzyme function exist at both these loci. The frequencies of homozygous GSTM1 and GSTT1 deletion carriers are very high in most of the populations studied to date. The aim of this study was to investigate the frequencies of GSTM1 and GSTT1 genotypes among the Turabah population in Saudi Arabia in comparison with the data published for some other Arabic populations. The subjects consisted of 164 unrelated healthy individuals from the Turabah population. GST genotyping was performed by multiplex polymerase chain reaction-based methods. The GSTM1 deletion homozygosity was 56.1% and GSTT1 deletion homozygosity was 20.7%, while the GSTM1 and GSTT1 double-deletion homozygosity was 11.0%. Comparison with published data from Bahraini, Lebanese, and Tunisian populations demonstrated no significant difference for GSTM1 between these populations. The GSTT1 null-allele frequency was significantly lower than those for the Lebanese and Tunisian populations (P = 0.001) but similar to that for the Bahraini population (P = 0.099). Characterization of GST genetic polymorphisms in the Saudi population may aid in genetic studies on the association of GSTM1 and GSTT1 polymorphisms with disease risks and the pharmacogenetics of chemotherapy.

Short versus prolonged duration of therapy for Pseudomonas aeruginosa bacteraemia: a systematic review and meta-analysis.

The optimal duration of therapy for Pseudomonas aeruginosa bloodstream infection (PSA-BSI) is unknown, with prolonged therapy frequently favored due to severity of infection, patient complexity, risk of multi-drug resistance, and high mortality. We therefore conducted a systematic review and meta-analysis of studies with head-to-head comparison of short versus prolonged therapy for PSA-BSI. A comprehensive search including Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus was performed. We pooled risk ratios using DerSimonian-Laird random effects model and performed subgroup analysis of outcomes including all-cause mortality, recurrent infection, and composite of these outcomes among patients receiving short versus prolonged therapy for PSA-BSI. Heterogeneity was assessed by the I2-index. Risk of bias for cohort studies was assessed using ROBINS-I tool. Of the 908 identified studies, six were included in the systematic review and five studies with head-to-head comparison of treatment duration were assessed in the meta-analysis, totalling 1746 patients. No significant difference in propensity score-weighted composite outcome (30-day all-cause mortality or recurrent infection) was noted between patients receiving short or prolonged therapy, with a pooled RR risk ratio of 0.80 (95% CI confidence interval 0.51-1.25, P=0.32; I2 = 0%). Additionally, duration of therapy did not impact individual outcomes of 30-day all-cause mortality or recurrent/persistent infection. Our meta-analysis demonstrated that short duration of antimicrobial therapy may have similar efficacy to prolonged treatment for PSA-BSI. Future randomized trials will be necessary to definitively determine optimal management of PSA bacteraemia.

Factors Associated with Israeli Arab Women Anxiety and Depression During the COVID-19 Pandemic.

BACKGROUND: Reports have shown that women suffered from anxiety, stress, depression, and fatigue during the COVID-19 pandemic more than men. No study so far has examined the effect of the pandemic among the Arab minority in Israel. OBJECTIVES: To examine the associations between levels of pandemic fatigue and stress of Israeli Arab women, and their anxiety and depression, along with their socio-demographic and socio-economic characteristics. METHODS: A Cohen and Williamson questionnaire, which was based on a Likert scale, was distributed by the snowball method through social networks. Bivariate associations between the psycho-social and demographic characteristics and anxiety and depression were assessed using t-tests, chi-square tests, Z tests, and Pearson correlations. Multiple linear regressions were used to evaluate the associations with anxiety and depression, and the mediation model was examined with path analysis with bootstrapping. RESULTS: Among 2294 Israeli Arab mothers who participated in the study, 63.7% were in the clinical range for anxiety, 67.4% for depression, and 57.5% for both anxiety and depression. Low economic status, pandemic fatigue, living in closed communities, and stress were related to anxiety and depression. Pandemic fatigue was positively related to stress, which was positively related to both anxiety and depression (standardized indirect effect = 0.137, SE = 0.014, 95%CI = 0.111, 0.164, p < .001; vs. 0.133, SE = 0.013, 95%CI = 0.108, 0.160, p < .001 respectively). The contribution of stress to anxiety and depression was significantly greater than that of pandemic fatigue (Z = 19.43 and Z = 18.04, p < .001, for anxiety and depression, respectively). CONCLUSIONS: Demographic characteristics may put Arab women at a higher risk of anxiety and depression. Elevated stress alongside high fatigue may trigger mental health difficulties. The welfare of minorities should be addressed by policymakers in relation to their demographic needs.

Estimating Proportion and Barriers of Medication Error Reporting Among Nurses in Hail City, Saudi Arabia: Implications for Improving Patient Safety.

Background: Determining the proportion of nurses reporting medication errors (MEs) and identifying the barriers they perceive in ME reporting are crucial to encourage nurses to actively report MEs. Objective: This study aimed to determine the proportion of nurses experiencing and reporting MEs, perceived barriers to reporting MEs and their association with nurses' sociodemographic and work-related characteristics. Methods: A cross-sectional study was conducted among 350 nurses from June to November 2023. Data about sociodemographic and work-related characteristics, and ME reporting, were collected using a validated self-administered questionnaire. Results: The study found that 34.3% of nurses reported MEs, while 11.1% reported experiencing MEs during their practice. ME reporting was higher proportion among nurses who were older than 40 years (52.1%), males (41.4%), held a master's degree (58.7%), Saudi nationals (37.8%), experienced for more than 10 years (43.1%), working in intensive care units (44.3%), working for 48 hours or more per week (39.7%), working in hospitals with a nurse-to-patient ratio of 1:3 (44.9%) and having a system for incident reporting (37.7%) and with no training on patient safety (44.6%) compared to their counterparts. The rate of experiencing MEs was higher proportion among nurses who were older than 40 years (16.7%), males (17.3%), married (14.8%), Saudi nationals (13.4%), experienced for more than 10 years (15.6%) and with no training on patient safety (15.3%) compared to their counterparts. Lack of knowledge of the person responsible for reporting MEs was the most frequent perceived barrier to ME reporting (66.6%), followed by fears of blame (65.4%). Conclusion: In this study, nurses reported and experienced MEs during their practice. Most nurses perceive the lack of knowledge and fear of blame or disciplinary actions as barriers to reporting. Healthcare administrators should implement educational programs and workshops to increase nurses' awareness of ME reporting.

A Sensitive Liquid Chromatography-Mass Spectrometric Method for Determination of Bisoprolol in Rat Serum after Pre-Column Derivatization.

Two derivatization regents were reacted with bisoprolol (BIS), followed by liquid-chromatography-mass spectrometric analysis. 3-Bromomethyl-propyphenazone (BMP) and dansyl-chloride (Dns-Cl) were reacted via the secondary amino group using a catalyst to accelerate the reaction progress and completeness with minimal reaction byproducts. The sensitivity and the ionization efficiency of both BIS-methyl-propyphenazone (BIS-MP) and BIS-Dns via electrospray ionization were studied. The sensitivity of BIS-MP was superior to BIS-Dns. The derivatization procedure, extraction procedure, and LC-MS method were optimized and validated to achieve the monitoring of BIS in rat serum at a picogram scale. The calibration curve showed a regression coefficient value of 0.999 within a concentration spanning a range of 10-500 pg/mL. The detection limit and quantitation were 4 and 10 pg/mL, respectively. The intraday and inter-day precision values (% relative standard deviation) ranged from 0.53 to 6.91%, whereas the accuracy values (expressed as % error) ranged from -4.20 to -0.77%. The pharmacokinetic parameters were: 15,280 pg/mL for a maximum concentration of BIS (Cmax) at the maximum time (Tmax) of 1 h. BIS's elimination half-life (t1/2) was determined to be 3 h. The value of the area under the concentration-time curve (AUC0 - t) was 34,370 pg/mL h.

Assessment of the Perception and Worries of Saudi Healthcare Providers About the Application of Artificial Intelligence in Saudi Health Facilities.

Objective This study is aimed at assessing the perception and worries of Saudi healthcare providers about the application of artificial intelligence (AI) in Saudi healthcare facilities. Methods The study adopted a cross-sectional study involving 1026 Saudi healthcare providers between January 2023 and April 2023. The target population was healthcare providers across Saudi health facilities. Online questionnaires were administered through social media platforms. Data were analyzed using SPSS Statistics, version 26.0 (IBM Corp., Armonk, NY) to obtain important insights. Results The results of this study indicated that more than half (55.2%) of the respondents had good knowledge of AI, with (48.1%) of them being familiar with the application of AI in their specialty. A good proportion of the participants (57.9%) knew at least one term about the difference between machine learning and deep learning. More than half (69.9%) of the participants indicated that they had at one point in time used speech recognition or transcription application in their work. A large section (73.3%) of healthcare providers believed that AI would replace them at their job. A vast majority (84.9%) of the participants agreed that collaboration between medical schools with engineering and computer science faculties could be a game changer to provide a road for incorporating AI into medical curricula. The mean perception of AI in this study was 37.6 (SD=8.41; range 0-241). Age, level of health, health profession, and working experience all significantly impacted the positive perception score (p=0.021; p=0.031; p=0.041; p=0.026). However, there was no significant association between gender, nationality, and Saudi regions with a mean positive perception score. Conclusion There was a positive perception of AI among Saudi healthcare providers. Even though a substantial majority of Saudi healthcare providers were worried that AI would replace their jobs, the study revealed that AI serves as a crucial practitioner's tool rather than a physician's replacement.

Quantifying screening ion excesses in single-molecule force-extension experiments.

We derive a thermodynamic identity that allows one to infer the change in the number of screening ions that are associated with a charged macromolecule as the macromolecule is continuously stretched. Applying this identity to force-extension data on both single-stranded and double-stranded DNA, we find that the number of polymer-associated ions depends nontrivially on both the bulk salt concentration and the bare rigidity of the polymer, with single-stranded DNA exhibiting a relatively large decrease in ion excess upon stretching. We rationalize these observations using simple models for polyelectrolyte extension.

Recent Advances in Biodegradable Polymers and Their Biological Applications: A Brief Review.

The rising significance of the field of biopolymers has driven the rapid progress of this distinctive class of polymeric materials in the past decades. Biodegradable polymers have acquired much attention because they play an essential role in humans' lives due to their specific tunable electrical conductivity and biodegradability characteristics, making them fascinating in many applications. Herein, we debated the recent progress in developing biodegradable polymers and their applications. Initially, we introduce the basics of conducting and biodegradable polymers, trailed by debates about the effective strategies currently used to develop biopolymers. Special importance will focus on the uses of biodegradable polymers in drug delivery and tissue engineering, as well as wound healing, demonstrating the recent findings, and uses of several biodegradable polymers in modern biological uses. In this review, we have provided comprehensive viewpoints on the latest progress of the challenges and future prospects involving biodegradable polymers' advancement and commercial applications.

A facile synthesis of visible light driven Ni3V2O8 nano-cube/BiVO4 nanorod composite photocatalyst with enhanced photocatalytic activity towards degradation of acid orange 7.

Photocatalysis is one of the promising method to degrade harmful organic pollutants under visible light exposure. In this work, a novel Ni3V2O8/BiVO4 nanocomposite has been prepared by one-pot hydrothermal method, and investigated through X-ray diffraction, FT-IR, UV-visible diffuse reflectance spectroscopy, scanning and transmission electron microscopy and photoluminescence techniques. Subsequently, the photocatalytic performance of Ni3V2O8/BiVO4 nanocomposite has been examined by degrading AO7 under visible light illumination. The photocatalytic efficiency of the optimized 1:2 ratio of Ni3V2O8/BiVO4 nanocomposite photocatalyst is found to be 87% with a rate constant value of 0.03387 min-1 which are higher than those of other prepared photocatalysts. This nanocomposite exhibits excellent stability even after 3 three cycles, and shows 1.135- and 1.17-times higher photocurrent intensity than pure BiVO4 and Ni3V2O8 respectively. The mechanism for the degradation of AO7 over Ni3V2O8/BiVO4 nanocomposite photocatalyst has been proposed.

Strength Capacity and Failure Mode of Shear Connectors Suitable for Composite Cold Formed Steel Beams: Numerical Study.

In this paper, the findings of numerical modeling of the composite action between normal concrete and Cold-Formed Steel (CFS) beams are presented. To obtain comprehensive structural behavior, the numerical model was designed using 3-D brick components. The simulation results were correlated to the experimental results of eight push tests, using three types of innovative shear connectors in addition to standard headed stud shear connectors, with two different thicknesses of a CFS channel beam. The proposed numerical model was found to be capable of simulating the failure mode of the push test as well as the behavior of shear connectors in order to provide composite action between the cold-formed steel beam and concrete using the concrete damaged plasticity model.

Abdominal aorta measurements by a handheld ultrasound device compared with a conventional cart-based ultrasound machine.

BACKGROUND: Ultraportable or pocket handheld ultrasound devices (HUD) may be useful for large-scale abdominal aortic aneurysm screening. However, the reproducibility of measurements has not been compared with conventional cart-based ultrasound machines. OBJECTIVES: Investigate the intra- and inter-operator reproducibility of a HUD compared with a conventional ultrasound machine for aortic screening. DESIGN: Analytical, cross-sectional. SETTING: Ultrasound department at a large tertiary care hospital in Riyadh. PATIENTS AND METHODS: Eligible male participants aged ≥60 years were invited to participate upon arriving for a non-vascular ultrasound appointment. Three repeated anteroposterior measurements of the transverse aorta were made at the proximal and distal locations for each machine before repeating the measurements on a subset of participants by a second blinded operator. Intraclass correlation coefficients (ICC) and the Bland-Altman method were used to analyze reproducibility. MAIN OUTCOME MEASURE: Inter-system and intra- and inter-operator ICCs. SAMPLE SIZE: 114 males with repeated measurements by second operator on a subset of 35 participants. RESULTS: The median age (interquartile range) of participants was 68 years (62-74 years). The intra- and inter-operator ICCs were all >0.800 showing almost perfect agreement except for the inter-operator reproducibility at the proximal location using a conventional machine (ICC= 0.583, P=.007) and the Butterfly device (ICC=0.467, P=.037). The inter-system ICCs (95% CI) were 0.818 (0.736-0.874) and 0.879 (0.799-0.924) at the proximal and distal locations, respectively. The mean difference in aortic measurement between the ultrasound systems was 0.3 mm (1.7%) in the proximal location and 0.6 mm (3.6%) in the distal location. In total, >91% of the difference in measurements between the machines was <3 mm. The mean scanning time was 4:16 minutes for the conventional system and 3:53 minutes for the HUD (P=.34). CONCLUSIONS: Abdominal aortic screening using a HUD was feasible and reliable compared with a conventional ultrasound machine. A pocket HUD should be considered for large-scale screening. LIMITATIONS: No cases of abdominal aortic aneurysm in the sample and lack of blinding. CONFLICT OF INTEREST: None.

Evaluation of Soil Contamination with Industrial Waste Effluent in Riyadh, Saudi Arabia.

BACKGROUND AND OBJECTIVE: Currently, in Saudi Arabia, wastewater production has increased manifolds due to onset of mega projects. The main objective of this study was to evaluate the soil contamination due to land disposal of industrial waste effluents. MATERIALS AND METHODS: Soil and water samples were collected from different depth and distances from the wastewater pond. Soil and water samples were analyzed for physical and chemical contents. The regression and other statistically techniques were applied for data analysis. RESULTS: Soil texture was sandy loam to sandy clay loam and was calcareous. Soil salinity was 80.3 dS m-1 near the pond and was normal after 100 m from the pond. Among the various heavy metals Cr showed more mobility than As and Mo. CONCLUSION: Soil was sandy loam to sandy clay loam containing gravels between 29.2-43.6% and was calcareous. Soil salinity was 80.3 and 3.2 dS m-1 near the pond and at 100 m distance, respectively. The mobility index of Cr was high followed by As and Mo in descending order.

Toxic heavy metal cadmium removal using chitosan and polypropylene based fiber composite.

The aim of the present work was to evaluate the performance of polypropylene (PP)/sisal fiber (SF)/banana fiber (BF) and chitosan-based hybrid (chitosan(CS)/SF)/BF) composite materials for the adsorptive removal of cadmium (Cd) ions from water waste. Polypropylene is harnessed for its importance in forming strong composite materials for various applications. Chitosan biopolymer encloses a great deal of amino and hydroxyl groups, which provide effective removal of Cd ions from wastewater. The batch adsorption studies proved that the removal of Cd ions was pH-dependent and attained optimum at pH 5.5 for both the composites. Langmuir and Freundlich models were applied for the obtained experimental values. Based on the R2 values, it was evidenced that the adsorption process was best fitted with the Freundlich isotherm than Langmuir. The sorption capacity of CS/SF/BF hybrid composite (Cmax = 419 mg/g) is higher than PP/SF/BF composite (Cmax = 304 mg/g), and allows multilayer adsorption. Kinetics studies revealed that the pseudo-second-order model was followed during the removal of Cd ion from wastewater. The overall evaluation proved that though both the adsorbents are suitable for the removal of Cd ions, the efficiency of CS-based ternary composite material is better than PP-based composite.

Enhancement of biodiesel yield from a halophilic green microalga isolated under extreme hypersaline conditions through stepwise salinity adaptation strategy.

In the present study, a halophilic microalgal species was isolated from a hypersaline lagoon with salinity average of 45.3‰ and identified as Dunaliella salina KSA-HS022. It was further cultivated at a salinity range of 50-250‰, applied directly to batch cultures or through stepwise increase in a semi-continuous culture. The later showed the highest biomass productivity of 0.191 g L-1 d-1 at 125‰, which represented 45.8% higher than the corresponding batch culture (control). Oxidative markers in the control cultures were significantly higher than those of the adapted culture, confirming reduction of oxidative stress by adaptation. In addition, stepwise adaptation showed the highest lipid productivity of 56.5 mg L-1 d-1 at 150‰ (39.9% higher than the corresponding control), which resulted in the highest fatty acid methyl esters productivity. Moreover, stepwise increase of salinity up to 150‰ enhanced the biodiesel characteristics, offering a new route for enhanced biodiesel production at extraordinary salinity levels.

Direct pyrolysis and ultrasound assisted preparation of N, S co-doped graphene/Fe3C nanocomposite as an efficient electrocatalyst for oxygen reduction and oxygen evolution reactions.

Bifunctional electrocatalysts to enable efficient oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are essential for fabricating high performance metal-air batteries and fuel cells. Here, a defect rich nitrogen and sulfur co-doped graphene/iron carbide (NS-GR/Fe3C) nanocomposite as an electrocatalyst for ORR and OER is demonstrated. An ink of NS-GR/Fe3C is developed by homogeneously dispersing the catalyst in a Nafion containing solvent mixture using an ultrasonication bath (Model-DC150H; power - 150 W; frequency - 40 kHz). The ultrasonically prepared ink is used for preparing the electrode for electrochemical studies. In the case of ORR, the positive half-wave potential displayed by NS-GR/Fe3C is 0.859 V (vs. RHE) and for the OER, onset potential is 1.489 V (vs. RHE) with enhanced current density. The optimized NS-GR/Fe3C electrode exhibited excellent ORR/OER bifunctional activities, high methanol tolerance and excellent long-term cycling stability in an alkaline medium. The observed onset potential for NS-GR/Fe3C electrocatalyst is comparable with the commercial noble metal catalyst, thereby revealing one of the best low-cost alternative air-cathode catalysts for the energy conversion and storage application.

Enhanced ability of daniplestim and myelopoietin-1 to suppress apoptosis in human hematopoietic cells.

Modified and chimeric cytokines have been developed to aid in the recovery of hematopoietic precursor cells after myeloablative chemotherapy. The interleukin-3 (IL-3) receptor agonist, daniplestim, binds to the IL-3 receptor-alpha subunit with 60-fold greater affinity and induces cell proliferation and colony-forming unit formation 10- to 22-fold better than native IL-3. A chimeric cytokine, myelopoietin-1, composed of daniplestim and a G-CSF receptor agonist binds both the IL-3 and G-CSF receptors. While the in vivo effects of daniplestim and myelopoietin-1 are well described, the mechanisms by which they stimulate growth are not well understood. We have investigated the effects of daniplestim and myelopoietin-1 on the prevention of apoptosis in two human hematopoietic cell lines, OCI-AML.5 and AML 193. Daniplestim and myelopoietin-1 prevented apoptosis to a greater degree than native recombinant IL-3 or G-CSF as determined by annexin V/propidium iodide binding and TUNEL assays. Daniplestim and myelopoietin-1 promoted the maintenance of the mitochondrial membrane potential better than native IL-3 or G-CSF. These cytokines promoted a lower redox potential as higher levels of free radicals were detected after cytokine treatment than in cytokine-deprived cells implying increased respiration. These results indicate that daniplestim and myelopoietin-1 are able to prevent apoptosis in hematopoietic cells more effectively than native IL-3 and G-CSF. These effects of daniplestim and myelopoietin-1 may contribute to their effective ability to repopulate hematopoietic precursor cells after chemotherapy.