Green Synthesis of Controlled Shape Silver Nanostructures and Their Peroxidase, Catalytic Degradation, and Antibacterial Activity

Nanoparticles with unique shapes have garnered significant interest due to their enhanced surface area-to-volume ratio, leading to improved potential compared to their spherical counterparts. The present study focuses on a biological approach to producing different silver nanostructures employing Moringa oleifera leaf extract. Phytoextract provides metabolites, serving as reducing and stabilizing agents in the reaction. Two different silver nanostructures, dendritic (AgNDs) and spherical (AgNPs), were successfully formed by adjusting the phytoextract concentration with and without copper ions in the reaction system, resulting in particle sizes of ~300 ± 30 nm (AgNDs) and ~100 ± 30 nm (AgNPs). These nanostructures were characterized by several techniques to ascertain their physicochemical properties; the surface was distinguished by functional groups related to polyphenols due to plant extract that led to critical controlling of the shape of nanoparticles. Nanostructures performance was assessed in terms of peroxidase-like activity, catalytic behavior for dye degradation, and antibacterial activity. Spectroscopic analysis revealed that AgNDs demonstrated significantly higher peroxidase activity compared to AgNPs when evaluated using chromogenic reagent 3,3',5,5'-tetramethylbenzidine. Furthermore, AgNDs exhibited enhanced catalytic degradation activities, achieving degradation percentages of 92.2% and 91.0% for methyl orange and methylene blue dyes, respectively, compared to 66.6% and 58.0% for AgNPs. Additionally, AgNDs exhibited superior antibacterial properties against Gram-negative E. coli compared to Gram-positive S. aureus, as evidenced by the calculated zone of inhibition. These findings highlight the potential of the green synthesis method in generating novel nanoparticle morphologies, such as dendritic shape, compared with the traditionally synthesized spherical shape of silver nanostructures. The synthesis of such unique nanostructures holds promise for various applications and further investigations in diverse sectors, including chemical and biomedical fields.

Thermophoretic Movement Transport of Reactive Casson Nanofluid on Riga Plate Surface with Nonlinear Thermal Radiation and Uneven Heat Sink/Source

The flow of magnetized Casson nanofluid past a Riga surface is examined in this study. The model scrutinizes the impacts of nonlinear radiative, uneven heat sink/source, thermophoretic movement and chemical reaction. Additionally, model is considered water based nanofluid with nanoparticles CuO (Copper Oxide) and MgO (Magnesium Oxide). The flow mechanics transport through Riga plate is developed using coupled system of higher order equations have been mutated into ordinary order from partial order utilizing established similarity transform. These nonlinear equations are calculated by the usage of through the Galerkin weighted residual method (GWRM) along with Simpson’s one-third rule and procured results are visualized graphically. Verifications of attained numerical outcomes through available literature for limiting case are also presented and found in excellent agreement. Further, the results of engineering physical parameters were also highlighted. More so, the analysis show that an increment in the Casson term causes rise in the temperature profile for CuO and MgO nanofluid and also dominant behavior is noted in case of CuO nanofluid comparing with MgO nanofluid. Furthermore, higher values of volume fraction parameter rises the both velocity profiles f′ (η), g′ (η) for both MgO and CuO nanofluid cases.

Comparing one-year outcomes of invasive versus medical management of patients with prior coronary artery bypass graft surgery presenting with non-ST elevation myocardial infarction

Background

Early percutaneous coronary intervention (PCI) has a Class 1A recommendation for patients with non-ST elevation myocardial infarction (NSTEMI). However, the benefits of this invasive approach in patients with previous coronary artery bypass graft (CABG) surgery are uncertain, as these patients have previously been excluded from pivotal trials.

Purpose

We hypothesised that routine invasive management in patients with previous CABG presenting with NSTEMI, but otherwise medically stable, carried similar prognostic outcomes to patients who were medically managed.

Methods

This single centre retrospective observational study screened patients with prior CABG presenting with NSTEMI between January 2015 and December 2019. Patients either underwent coronary angiography with or without PCI at their physician's discretion or received standard acute coronary syndrome (ACS) medical therapy. Follow up time was 365 days from admission date, and clinical, demographic, procedural and outcome data were collected. The primary endpoint was major adverse cardiac events (MACE), a composite of all-cause mortality and rehospitalisation for unstable angina, myocardial infarction, or heart failure.

Results

The study included 267 patients (mean ±SD age: 72±10 years, 82% male), of whom 80.1% (N=214) underwent cardiac catheterisation, and 19.9% (N=53) only received standard ACS medical therapy. Amongst the invasive group, 65.4% (N=140) received PCI. No one was referred for re-do CABG. At 1-year follow up, the primary composite outcome occurred in 18 (13%) patients in the PCI group, 13 (18%) in those managed conservatively following angiography, and in 27 (51%) patients receiving medical therapy only. Cox regression modelling showed no significant difference in the 1-year primary endpoint amongst those having an angiogram who received PCI versus those treated medically after invasive assessment (HR: 0.75 [95% CI: 0.38–1.48; P=0.412]). Previous revascularisation with PCI (HR: 1.90 [CI, 1.11–3.24; P=0.018]) and chronic kidney disease (CKD) (HR: 2.60 [CI, 1.56–4.34; P<0.001]) at any stage, were the most important predictors of poor outcomes in CABG patients with NSTEMI irrespective of management strategy.

Conclusion

Patients with previous CABG who are admitted with NSTEMI who were not considered suitable for invasive angiography experienced significantly higher rates of MACE at 1-year follow up. The presence of CKD or previous PCI were key indicators of poor outcomes irrespective of management strategy. Outcomes amongst those deemed fit enough for invasive angiography were similar irrespective of treatment, suggesting that additional non-invasive testing may help further define which patients would benefit from an invasive strategy.

Funding Acknowledgement

Type of funding sources: None.

402 ‘TAP it’: trainee led initiative to reduce unnecessary blood testing in a paediatric emergency department

Aims/Objectives/Background

Unnecessary blood testing in the paediatric emergency department (PED) is a potential starting point for diagnostic dilemma, anxiety to families and increased healthcare costs. We hypothesized that a significant number of blood tests are performed instinctively rather than clinically indicated. This stimulated a quality improvement initiative to enlighten trainees on the utility of blood tests while aiming to enhance clinical decision making.

Methods/Design

Children presenting to the acute care team in a tertiary PED who had blood tests over a 2-week period in April 2019 were enrolled. Blood tests requested were interpreted in line with presenting features and clinical impression. Following implementation of changes (posters, QI champions, educational sessions), a repeat analysis was done over a 2-week period in October 2019.

Results/Conclusions

One hundred and one children in the first cycle were enrolled. Blood testing analysis revealed that 70%, 47%, and 32% had liver bloods, bone profile, and clotting testing done, respectively. Over half of these blood tests had no clear clinical indication. The yield of the tests performed without clinical indication was 0%. Case vignettes were attempted by trainees and ANPs to evaluate their attitudes to blood test requests. Number of requested blood tests not clinically indicated was lower than anticipated; probably explained by self-thought processes. Blood tests performed on 100 children in the second cycle demonstrated a significant reduction in tests done without clear clinical indication. Liver bloods, clotting screen, bone profile tests were performed on 40%, 24% and 27% respectively in the second cycle.

The utility of blood tests may be an under recognised subject in paediatric training which needs addressing. This project typified positive impact of culture change via QI champions and educational sessions. Implementation of such changes is sustainable with an estimated savings of at least £500/month.

Retinopathy of prematurity screening at ≥30 weeks: urinary NTpro-BNP performance

AIM

Urinary N-terminal B-type natriuretic peptide NTproBNP levels are associated with the development of retinopathy of prematurity (ROP) in infants <30 weeks of gestation. The incidence of ROP in more mature infants who meet other ROP screening criteria is very low. We therefore aimed to test whether urinary NTproBNP predicted ROP development in these infants.

METHODS

Prospective observational study in 151 UK infants ≥30 + 0 weeks of gestation but also <32 weeks of gestation and/or <1501 g, to test the hypothesis that urinary NTproBNP levels on day of life (DOL) 14 and 28 were able to predict ROP development.

RESULTS

Urinary NTproBNP concentrations on day 14 and day 28 of life did not differ between infants with and without ROP (medians 144 vs 128 mcg/mL, respectively, p = 0.86 on DOL 14 and medians 117 vs 94 mcg/mL, respectively, p = 0.64 on DOL28).

CONCLUSION

The association previously shown for infants <30 completed weeks between urinary NTproBNP and the development of ROP was not seen in more mature infants. Urinary NTproBNP does not appear helpful in rationalising direct ophthalmoscopic screening for ROP in more mature infants, and may suggest a difference in pathophysiology of ROP in this population.

Accuracy of co-morbidity data in patients undergoing abdominal wall hernia repair: a retrospective study

OBJECTIVES

To determine the baseline accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of routinely collected co-morbidity data in patients undergoing abdominal wall hernia repair.

METHODS

All patients aged > 18 who underwent umbilical, para-umbilical, inguinal or incisional hernia repair between 1 January 2015 and 1 November 2016 were identified. All parts of the clinical notes were searched for co-morbidities by two authors independently. The following co-morbidities were considered: hypertension, ischaemic heart disease (IHD), diabetes, asthma, chronic obstructive pulmonary disease (COPD), cerebrovascular disease (CVD), chronic kidney disease (CKD), hypercholesterolemia, obesity and smoking. The co-morbidities data from clinical notes were compared with corresponding data in hospital episode statistics (HES) database to calculate accuracy, sensitivity, specificity, PPV and NPV of HES codes for co-morbidities. To assess the agreement between clinical notes and HES data, we also calculated Cohen's Kappa index value as a more robust measure of agreement.

RESULTS

Overall, 346 patients comprising 3460 co-morbidity codes were included in the study. The overall accuracy of HES codes for all co-morbidities was 77% (Kappa: 0.13). When calculated separately for each co-morbidity, the accuracy was 72% (Kappa: 0.113) for hypertension, 82% (Kappa: 0.232) for IHD, 85% (Kappa: 0.203) for diabetes, 86% (Kappa: 0.287) for asthma, 91% (Kappa: 0.339) for COPD, 92% (Kappa: 0.374) for CVD, 94% (Kappa: 0.424) for CKD, 74% (Kappa: 0.074) for hypercholesterolemia, 71% (Kappa: 0.66) for obesity and 24% (Kappa: 0.005) for smoking. The overall sensitivity, specificity, PPV and NPV of HES codes were 9, 100, 100, and 77%, respectively. The results were consistent when individual co-morbidities were analyzed separately.

CONCLUSIONS

Our results demonstrated that HES co-morbidity codes in patients undergoing abdominal wall hernia repair are specific with good positive predictive value; however, they have substandard accuracy, sensitivity, and negative predictive value. The presence of a relatively large number of false negative or missed cases in HES database explains our findings. Better documentation of co-morbidities in admission clerking proforma may help to improve the quality of source documents for coders, which in turn may improve the accuracy of coding.

An international comparison of retinopathy of prematurity grading performance within the Benefits of Oxygen Saturation Targeting II trials

Purpose

To investigate whether the observed international differences in retinopathy of prematurity (ROP) treatment rates within the Benefits of Oxygen Saturation Targeting (BOOST) II trials might have been caused by international variation in ROP disease grading.

Methods

Groups of BOOST II trial ophthalmologists in UK, Australia, and New Zealand (ANZ), and an international reference group (INT) used a web based system to grade a selection of RetCam images of ROP acquired during the BOOST II UK trial. Rates of decisions to treat, plus disease grading, ROP stage grading, ROP zone grading, inter-observer variation within groups and intra-observer variation within groups were measured.

Results

Forty-two eye examinations were graded. UK ophthalmologists diagnosed treat-requiring ROP more frequently than ANZ ophthalmologists, 13.9 (3.49) compared to 9.4 (4.46) eye examinations, P=0.038. UK ophthalmologists diagnosed plus disease more frequently than ANZ ophthalmologists, 14.1 (6.23) compared to 8.5 (3.24) eye examinations, P=0.021. ANZ ophthalmologists diagnosed stage 2 ROP more frequently than UK ophthalmologists, 20.2 (5.8) compared to 12.7 (7.1) eye examinations, P=0.026. There were no other significant differences in the grading of ROP stage or zone. Inter-observer variation was higher within the UK group than within the ANZ group. Intra-observer variation was low in both groups.

Conclusions

We have found evidence of international variation in the diagnosis of treatment-requiring ROP. Improved standardisation of the diagnosis of treatment-requiring ROP is required. Measures might include improved training in the grading of ROP, using an international approach, and further development of ROP image analysis software.

A descriptive study of consent documentation

The aim of this study was to observe the error rate in the consent process of a university hospital and to illicit the opinions of the consenting doctors on the process. A prospective observational review of theatre consent forms was performed along with an anonymous survey of non-consultant hospital doctors (NCHD's). No potential risks were documented in 95.3% of the 64 scrutinized consents and late alterations were required in 9%. Respondents to the NCHD survey estimated that they were unsure of the procedure or risks involved in an average of 29% of occasions. Interns admitted to being unsure of the details of the procedure in almost a third (32%) of cases, making them less well informed than their senior colleagues (p=0.024). This study highlights the difficulties encountered by consenting doctors, an issue which may lead to patient dissatisfaction, threaten the efficient running of a surgical unit and potentially expose its staff to avoidable litigation. It also recommends the use of multimedia adjuncts to facilitate both patient and doctor education in the consent process.

Interventions for infantile esotropia

BACKGROUND

Various aspects of the clinical management of infantile esotropia (IE) are unclear - mainly, the most effective type of intervention and the age at intervention.

OBJECTIVES

The objective of this review was to assess the effectiveness of various surgical and non-surgical interventions for IE and to determine the significance of age at treatment with respect to outcome.

SEARCH STRATEGY

Trials were identified from the Cochrane Central Register of Controlled Trials - CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) in The Cochrane Library (Issue 3 2004), MEDLINE (1966 to July 2004), EMBASE (1980 to August 2004) and LILACS (July 2004). We manually searched the conference proceedings of the European Strabismological Association (ESA) (1975-1997, 1999-2002), International Strabismological Association (ISA) (1994) and American Academy of Paediatric Ophthalmology and Strabismus meeting (AAPOS) (1995-2003). Efforts were made to contact researchers who are active in the field for information about further published or unpublished studies.

SELECTION CRITERIA

Randomised trials comparing any surgical or non-surgical intervention for infantile esotropia.

DATA COLLECTION AND ANALYSIS

Each reviewer independently assessed study abstracts identified from the electronic and manual searches.

MAIN RESULTS

No studies were found that met our selection criteria and therefore none were included for analysis.

AUTHORS' CONCLUSIONS

The main body of literature on interventions for IE are either retrospective studies or prospective cohort studies. It has not been possible through this review to resolve the controversies regarding type of surgery, non-surgical intervention and age of intervention. There is clearly a need for good quality trials to be conducted in these areas to improve the evidence base for the management of IE.

Pitfalls in the management of a child with mild haemophilia A and a traumatic hyphaema

A 12-year-old boy presented with a traumatic hyphaema that failed to settle with the standard treatment. Subsequent investigation showed that despite a normal APTT, he had a low factor VIII:C. Treatment with DDAVP precipitated further bleeding despite correction of the fVIII:C to normal, possibly caused by the vasodilation induced by the therapy. Bleeding was effectively treated with recombinant fVIII concentrate. DDAVP may be contraindicated in mild Haemophilia and von Willebrand patients for treatment of traumatic hyphaema.

Reduced density of intramembrane particles in erythrocytes of dystrophic chickens

The intramembrane particles in erythrocytes of chickens with hereditary muscular dystrophy and normal controls were compared by the freeze-fracture technique. Reduction of particles in both fracture faces and greater clustering of them was found in dystrophic samples. The concept of a generalized membrane abnormality in dystrophic chickens is supported.

Degradation of ribonucleic acid in mouse fibroblasts treated with actinomycin

The cellular RNA content of mouse fibroblasts incubated with actinomycin decreases at a rate of about 1 to 1.5 per cent per hour, while DNA and protein content remain unchanged. This degradation affects nuclear and cytoplasmic RNA, ribosomal and soluble RNA. The breakdown products appear quantitatively in the acid-soluble fraction of the cells and the medium. Polynucleotides synthesized a short period (120 minutes) prior to exposure to actinomycin are degraded before those synthesized 8 to 12 hours previously.