Acceptorless dehydrogenation of alcohols and transfer hydrogenation of aldehydes in water using a single bi-functional, bi-state, water soluble ruthenium catalyst

A water soluble bi-functional, bi-state ruthenium catalyst has been developed using the 8-aminoquinoline ligand which responds to an acid-base stimuli and is catalytically active for two complementary reactions. The "Ru-amino state" is highly active for catalytic transfer hydrogenation of various aldehydes using formic acid as the hydrogen source resulting in a range of primary alcohols. On the other hand, the "Ru-amido state" is active for the acceptorless dehydrogenation of alcohols to yield carboxylate salts or ketones. The reactions can be carried out in air without an inert atmosphere and the products can be purified by simple extraction without the use of any chromatographic techniques. A range of functional groups which include electron-rich and deficient (hetero)arenes and alkenes, alkynes, halides, esters, cyano, and nitro groups, are all well tolerated, indicating excellent chemoselectivity for transfer hydrogenation.

Reuniting the Three Sisters: collaborative science with Native growers to improve soil and community health

Before Euro-American settlement, many Native American nations intercropped maize (Zea mays), beans (Phaseolus vulgaris), and squash (Cucurbita pepo) in what is colloquially called the "Three Sisters." Here we review the historic importance and consequences of rejuvenation of Three Sisters intercropping (3SI), outline a framework to engage Native growers in community science with positive feedbacks to university research, and present preliminary findings from ethnography and a randomized, replicated 3SI experiment. We developed mutually beneficial collaborative research agendas with four Midwestern US Native American nations. Ethnographic data highlighted a culturally based respect for 3SI as living beings, the importance it holds for all cultural facets of these Native nations, and the critical impact the practice has on environmental sustainability. One concern expressed by Native growers during ethnographic research was improving soil health-part of the rationale for establishing the 3SI agronomic experiment. To address this, we collaboratively designed a 3SI experiment. After 1 year, 3SI increased short-term soil respiration by 24%, decreased salt-extractable nitrate by 54%, had no effect on soil microbial biomass (but increased its carbon-to-nitrogen ratio by 32%) compared to the average of monoculture crops. The overarching purpose of this collaborative project is to develop a deeper understanding of 3SI, its cultural importance to Native communities, and how reinvigorating the practice-and intercropping in general-can make agroecosystems more sustainable for people and the environment.

Novel benchmark values for redo liver transplantation – does the outcome justify the effort?

Objective

In the era of organ shortage, redo liver transplantation (reLT) is frequently discussed in terms of expected poor outcome, high cost and therefore wasteful resources. However, there is a lack of benchmark data to reliably assess outcomes after reLT. The aim of this study was to define the ideal reLT case, and to establish clinically relevant benchmark values for best achievable outcome in reLT.

Methods

We collected data on reLT between January 2010 and December 2018 from 22 high volume transplant centers on three continents. Benchmark cases were defined as recipients with model of end-stage liver disease score <=25, absence of portal vein thrombosis, no mechanical ventilation before surgery, receiving a graft from a donor after brain death. In addition, early reLT including those for primary non-function (PNF) were excluded. Clinically relevant endpoints covering intra- and postoperative course were selected and complications were graded by severity using the Clavien-Dindo classification and the comprehensive complication index (CCI). The benchmark cutoff for each outcome was derived from the 75th percentile of the median values of all benchmark centers, indicating the “best achievable” result. To assess the utility of the newly established benchmark values, we analyzed patients who received reLT for PNF (non-benchmark patients).

Results

Out of 1110 reLT 413 (37.2%) qualified as benchmark cases. Benchmark values included: Length of intensive care unit and hospital stay: <=6 and <=24 days, respectively; Clavien-Dindo grade >=3a complications and the CCI at 1 year: <=76% and <=72.2, respectively; in-hospital and 1-year mortality rates: <=14.0% and <=14.3%, respectively. The cutoffs for transplant-specific complications such as biliary complications at 1 year, outflow problems at 1 year and hepatic artery thrombosis at discharge were <=27.3%, <=2.5% and <=4.8%, respectively. Patients receiving a reLT for PNF showed mean outcome values all outside the reLT benchmark values. In-hospital mortality rate was 34.4% and the mean CCI at discharge 68.8.

Conclusion

ReLT remains associated with high morbidity and mortality. The availability of benchmark values for outcome parameters of reLT may serve for comparison in any future analyses of individuals, patient groups, or centers, but also in the evaluation of new therapeutic strategies and principles.

A70 SEVERE ENTERITIS AND IGA VASCULITIS IN A PEDIATRIC PATIENT WITH ULCERATIVE COLITIS ON VEDOLIZUMAB

Background

Pediatric Ulcerative Colitis (UC) is often unsatisfactorily controlled using ‘conventional’ therapies, thus there has been increasing use of biologic therapies and small molecules to try and improve rates of clinical remission and mucosal healing. Consequently, pediatric gastroenterologists and generalists should be aware of the complications and side effects of these newer molecules. Vedolizumab (VDZ) is a fully humanised anti-integrin therapy that is thought to limit systemic side effects given its gut-specific mechanism.

Aims

Here we report the unique case of a 14-year-old male with UC on vedolizumab presenting with severe abdominal pain, GI bleeding, markedly elevated inflammatory markers and subsequent purpura.

Methods

N/A

Results

A diagnosis of IgA vasculitis (IgAV) was made after extensive imaging, endoscopy and subspecialty consultation. Clinical course was complicated but ultimately responded to high dose steroid treatment without cessation of VDZ.

Conclusions

This case illustrates a potentially independent pathway behind IgAV in a patient on a gut-selective therapy with UC. This is the first pediatric case of vasculitis in a patient with UC on VDZ.

Funding Agencies

None

Functional Outcome of Closed Reduction and Extension Casting in Forearm Fractures in Children

Introduction

Fractures in children are extremely common scenarios encountered by orthopedicians. Conservative treatment has been the most preferred choice for the management of diaphyseal forearm fractures. Traditionally, pediatric forearm fractures are treated by above elbow plaster cast with the elbow flexed to 90 degrees. The purpose of this study was to evaluate the functional and radiological outcomes of children treated with closed reduction and extension casting for forearm fractures.

Patient and methods

This is a prospective study evaluating the functional and radiological outcomes of 30 children of less than the age of 14 years and without pathological fractures, treated with closed reduction and extension casting for forearm fractures, either both radius and ulna or radius or ulna at middle third level, who reported to the Department of Orthopedics, Dr. D.Y. Patil Medical College, Hospital, and Research Center, Pune, India, between September 2019 and March 2022.

Results

The mean pre-operative angulation in radius (antero-posterior {AP}) was 22.7, radius (lateral {LAT}) was 24.2, ulna (AP) was 31.2, and ulna (LAT) was 29.2. The immediate post-operative angulation of radius (AP) was 0.7, radius (LAT) was 3.2, ulna (AP) was 0.6, and ulna (LAT) was 4.9. Cast status at two weeks, 83.3% had intact cast and 16.7% had loosened casts. Post removal, most patients had a good rotation of motion (ROM) at three and six weeks.

Conclusion

Casting with extended elbow is much better as compared to flexion casting in the hands of a trainee doctor. Furthermore, chances of loss of reduction are negligible in extension casting as compared to flexion casting.

Preoperative MRI Assessment of Hamstring Tendons to Predict the Quadruple Hamstring Graft Diameter in Anterior Cruciate Ligament Reconstruction

Introduction

The cross-sectional area (CSA) and length of an individual's hamstring tendons are both variable, making it challenging for the operating surgeon to generate an ideal size graft during arthroscopic anterior cruciate ligament (ACL) reconstruction surgery. If we can predict the hamstring graft diameter using MRI (a routine radiological investigation used to diagnose knee pathology), this information, if obtained before surgery rather than after the harvesting of the hamstring tendons, may influence the graft choice and allow us to successfully perform ACL reconstruction with sufficient graft diameter.

Aims

The aims of this study were to determine the reliability and accuracy of 3T MRI in predicting quadruple hamstring graft diameter for ACL reconstruction, to determine the statistical correlation between the CSA of hamstring tendons on MRI and intraoperative quadruple hamstring graft diameter, and to find out the minimum CSA of hamstring tendons (ST+GR) required for an 8 mm quadruple hamstring graft diameter.

Methods

This prospective diagnostic study included 50 patients diagnosed with complete ACL rupture. On MRI, we assessed the CSA of the semitendinosus and gracilis tendons at two levels: one at the joint line and the other at the level where the anteroposterior (AP) diameter of the medial femoral condyle is longest. The quadruple ST+GR graft was passed through 0.5 mm increments of holes in the block (Biotek (Winooski, Vermont) or Smith & Nephew, London, United Kingdom) intraoperatively, and the diameter of the hole that permitted smooth passage of the whole graft was taken as the quadruple graft diameter. The cutoff CSA required for a graft of sufficient size was calculated using simple logistic regression analysis. The correlation between CSA measurements on MRI and intraoperative quadruple hamstring graft diameter was determined using Pearson's rank correlation coefficient.

Results

The mean ST+GR CSA on MRI was 18.9 mm², the minimum CSA was 14.45 mm², and the maximum CSA was 23.8 mm². Pearson's correlation between the intraoperative quadruple hamstring graft diameter (mm) and ST+GR CSA on MRI was 0.838. The minimum ST+GR CSA required for an 8 mm quadruple hamstring graft diameter is 17.5 mm².

Conclusion

A strong statistical correlation between ST+GR CSA on MRI and intraoperative quadruple hamstring graft diameter was found (Pearson's correlation = 0.838, p-value = 0.000). Thus, MRI is a reliable radiological investigation that can be used to predict the quadruple hamstring graft diameter. This method can help orthopedic surgeons successfully perform ACL reconstruction surgery without any graft complications.  

Comparative evaluation of bond strength of resin cements with and without 10-methacryloyloxydecyl dihydrogen phosphate (mdp) to zirconia and effect of thermocycling on bond strength – An in vitro study

Background

To compare bond strength of resin cements with and without 10-Methacryloyloxydecyl Dihydrogen Phosphate (MDP) to zirconia and evaluate effect of thermocycling on bond strength.

Material and Methods

Standardised test specimens were fabricated as per ADA specification 131. Each Zirconia specimen was mounted in autopolymerzing acrylic resin material. The specimens were divided into 2 groups: Group 1 – specimens bonded with resin cement containing 10-MDP and Group II - specimens bonded with resin cement without 10-MDP. Forty samples of resin cement cylinders were prepared with dimensions of 6mm height and 4mm diameter in line with ADA specification 27 were cured onto the zirconia surface of 10mm x10mm x5mm using customised moulds. Specimens from each cement group were further divided into 2 subgroups: Subgroup A – Specimens that were not thermocycled and Subgroup B – Specimens that were thermocycled. Specimens were then subjected to tensile bond testing by using a Universal testing machine, the data were analysed using independent sample t test for bond strength and paired t test for effect of thermocycling. Statistical analysis used: Data was subjected to normalcy test (Shapiro-wilk test). Data showed normal distribution. Hence parametric test paired t test were applied.

Results

Paired t test revealed that the thermocycling affected the bond strength to zirconia. The highest bond strength was achieved for the resin cement with 10-MDP before thermocycling, whereas the lowest bond strength values were recorded for resin cement without 10-MDP after thermocycling.

Conclusions

Resin cement with 10-MDP showed superior bond strength to Zirconia than resin cement without 10-MDP. Adhesive failure was predominant at Zirconia and resin cement interface. Thermocycling had a significant effect on the bond strength of resin cements to zirconia, showing decreased bond strength.

Key words:10-MDP, Tensile Strength, Zirconia.

Hesitancy around low-dose CT screening for lung cancer

Lung cancer is the leading cause of cancer death worldwide. The absence of symptoms in early-stage (I/II) disease, when curative treatment is possible, results in >70% of cases being diagnosed at late stage (III/IV), when treatment is rarely curative. This contributes greatly to the poor prognosis of lung cancer, which sees only 16.2% of individuals diagnosed with the disease alive at 5 years. Early detection is key to improving lung cancer survival outcomes. As a result, there has been longstanding interest in finding a reliable screening test. After little success with chest radiography and sputum cytology, in 2011 the United States National Lung Screening Trial demonstrated that annual low-dose computed tomography (LDCT) screening reduced lung cancer-specific mortality by 20%, when compared with annual chest radiography. In 2020, the NELSON study demonstrated an even greater reduction in lung cancer-specific mortality for LDCT screening at 0, 1, 3 and 5.5 years of 24% in men, when compared to no screening. Despite these impressive results, a call to arms in the 2017 European position statement on lung cancer screening (LCS) and the widespread introduction across the United States, there was, until recently, no population-based European national screening programme in place. We address the potential barriers and outstanding concerns including common screening foes, such as false-positive tests, overdiagnosis and the negative psychological impact of screening, as well as others more unique to LDCT LCS, including appropriate risk stratification of potential participants, radiation exposure and incidental findings. In doing this, we conclude that whilst the evidence generated from ongoing work can be used to refine the screening process, for those risks which remain, appropriate and acceptable mitigations are available, and none should serve as barriers to the implementation of national unified LCS programmes across Europe and beyond.

Regulation of STAT3 signaling in IFNγ and IL10 pathways and in their cross-talk

The pro-inflammatory IFNγ-STAT1 pathway and anti-inflammatory IL10-STAT3 pathway elicit cellular responses primarily utilizing their canonical STATs. However IL10 mediated STAT1 and IFNγ mediated STAT3 activation is also observed, suggesting crosstalk of these functionally opposing signaling pathways can potentially reshape the canonical dynamics both STATs and alter the expression of their target genes. Herein, we measured the dynamics of STATs in response to different doses of IL10 or IFNγ and in their co-stimulation and employed quantitative modeling to understand the regulatory mechanisms controlling signal responses in individual and co-simulation scenarios. Our experiments show, STAT3 in particular, exhibits a bell-shaped dose-response while treated with IFNγ or IL10 and our model quantiatively captured the dose-dependent dynamics of both the STATs in both pathways. The model next predicted and subsequent experiments validated that STAT3 dynamics would robustly remain IL10 specific when subjected to a co-stimulation of both IFNγ and IL10. Genes common to both pathways also exhibited IL10 specific expression during the co-stimulation. The findings thus uncover anovel feature of the IL10-STAT3 signaling axis during pathway crosstalk. Finally, parameter sampling coupled to information theory based analysis showed that bell-shaped signal-response of STAT3 in both pathways is primarily dependent on receptor concentration whereas robustness of IL10-STAT3 signaling axis in co-stimulation results from the negative regulation of the IFNγ pathway.

COVID-19-associated mucormycosis presenting to the Emergency Department-an observational study of 70 patients

BACKGROUND

Mucormycosis (MM) is a deadly opportunistic fungal infection and a large surge in COVID-19-associated mucormycosis (CAM) is occurring in India.

AIM

Our aim was to delineate the clinico-epidemiological profile and identify risk factors of CAM patients presenting to the Emergency Department (ED).

DESIGN

This was a retrospective, single-centre, observational study.

METHODS

We included patients who presented with clinical features or diagnosed MM and who were previously treated for COVID-19 in last 3 months of presentation (recent COVID-19) or currently being treated for COVID-19 (active COVID-19). Information regarding clinical features of CAM, possible risk factors, examination findings, diagnostic workup including imaging and treatment details were collected.

RESULTS

Seventy CAM patients (median age: 44.5 years, 60% males) with active (75.7%) or recent COVID-19 (24.3%) who presented to the ED in between 6 May 2021 and 1 June 2021, were included. A median duration of 20 days (interquartile range: 13.5-25) was present between the onset of COVID-19 symptoms and the onset of CAM symptoms. Ninety-three percent patients had at least one risk factor. Most common risk factors were diabetes mellitus (70%) and steroid use for COVID-19 disease (70%). After clinical, microbiological and radiological workup, final diagnosis of rhino-orbital CAM was made in most patients (68.6%). Systemic antifungals were started in the ED and urgent surgical debridement was planned.

CONCLUSION

COVID-19 infection along with its medical management have increased patient susceptibility to MM.

Calcium carbonate nano- and microparticles: synthesis methods and biological applications

Calcium carbonate micro- and nanoparticles are considered as chemically inert materials. Therefore, they are widely considered in the field of biosensing, drug delivery, and as filler material in plastic, paper, paint, sealant, and adhesive industries. The unusual properties of calcium carbonate-based nanomaterials, such as biocompatibility, high surface-to-volume ratio, robust nature, easy synthesis, and surface functionalization, and ability to exist in a variety of morphologies and polymorphs, make them an ideal candidate for both industrial and biomedical applications. Significant research efforts have been devoted for developing novel synthesis methods of calcium carbonate particles in micrometer and nanometer dimensions. This review highlights different approaches of the synthesis of calcium carbonate micro- and nanoparticles, such as precipitation, slow carbonation, emulsion, polymer-mediated method, including in-situ polymerization, mechano-chemical, microwave-assisted method, and biological methods. The applications of these versatile calcium carbonate micro- and nanoparticles in the biomedical field (such as in drug delivery, therapeutics, tissue engineering, antimicrobial activity, biosensing applications), in industries, and environmental sector has also been comprehensively covered.

Microbial production of omega-3 fatty acids: an overview

The essence of appropriate nutritional intake on a regular basis has a great impact in maintaining fundamental physiological functions and the body metabolism. Considering how pivotal maintaining a nourishing fat diet is to human health, Omega-3 fatty acids have gained a lot of attention in recent times. Omega-3 fatty acids (n-3 FAs) such as eicosapentaenoic acid (EPA) and DHA are considered as essential fatty acids (EFAs) offering enormous nutritional benefits: from playing a major role in the prevention and treatment of a number of human diseases, such as cardiovascular disorders and neurological disorders, to having anti-inflammatory properties, to providing joint support, etc. Hence, their incorporation into our daily diet is of great importance. Also, both EPA and DHA have been shown to be therapeutically significant in treating several infectious diseases. EFAs were initially thought to be marine in origin, produced by fishes. Consequentially, this led to the increase in the industrial extraction of fish oils for meeting the commercial need for of n-3-rich dietary supplements. Although fish oil supplementation met almost all of the dietary demand for EFAs, they did come with a fair share of drawbacks such as undesirable odour and flavour, heavy metal contamination, extinction of fish species, etc. Oleaginous micro-organisms are a promising alternative for the production of a more sustainable, consistent and quality production of n-3 FAs. Thus, the entire review focuses on understanding the eco-friendlier production of n-3 FAs by micro-organisms.

COVID-19: looking beyond the peak. Challenges and tips for radiologists in follow-up of a novel patient cohort

As the coronavirus pandemic evolves, the focus of radiology departments has begun to change. The acute phase of imaging a new disease entity whilst rationalising radiology services in the face of lockdown has passed. Radiologists are now becoming familiar with the complications of COVID-19, particularly the lung parenchymal and pulmonary vascular sequelae and are considering the impact follow-up imaging may have on departments already struggling with a backlog of suspended imaging in the face of reduced capacity. This review from the British Society of Thoracic Imaging explores both the thoracic and extra-thoracic complications of COVID-19, recognising the importance of a holistic approach to patient follow-up. The British Thoracic Society guidelines for respiratory follow-up of COVID-19 will be discussed, together with newly developed reporting templates, which aim to provide consistency for clinicians as well as an opportunity for longer-term data collection.