We report a 2D layered metal–organic framework (MOF) with wide channels named NUS-1 and its activated analogue NUS-1a composed of Zn4O-like secondary building units and tetraphenylethene ...(TPE)-based ligand 4,4′-(2,2-diphenylethene-1,1-diyl)dibenzoic acid. Due to its special structure, NUS-1a exhibits unprecedented gas sorption behavior, glass-transition-like phase transition under cryogenic conditions, and responsive turn-on fluorescence to various volatile organic compounds. Our approach using angular ligand containing partially fixed TPE units paves a way toward highly porous MOFs with fluorescence turn-on response that will find wide applications in chemical sensing.
Two tetraphenylethylene (TPE) bridged tetraimidazolium salts, H4L‐Et(PF6)4 and H4L‐Bu(PF6)4, were used as precursors for the synthesis of the dinuclear AgI and AuI tetracarbene complexes ...Ag2(L‐Et)(PF6)2, Ag2(L‐Bu)(PF6)2, Au2(L‐Et)(PF6)2, and Au2(L‐Bu)(PF6)2. The tetraimidazolium salts show almost no fluorescence (ΦF<1 %) in dilute solution while their NHC complexes display fluorescence “turn‐on” (ΦF up to 47 %). This can be ascribed to rigidification mediated by the restriction of intramolecular rotation within the TPE moiety upon complexation. DFT calculations confirm that the metals are not involved in the lowest excited singlet and triplet states, thus explaining the lack of phosphorescence and fast intersystem crossing as a result of heavy atom effects. The rigidification upon complexation for fluorescence turn‐on constitutes an alternative to the known aggregation‐induced emission (AIE).
Stop rotating! Tetraphenylethylene (TPE) bridged tetrakis‐NHC precursors display fluorescence turn‐on in dilute solution upon formation of organometallic chelate complexes. The fluorescence enhancement can be attributed to the rigidification of the TPE moiety, caused by restriction of its intramolecular rotation. This ridigification method for the fluorescence turn‐on constitutes an alternative approach to aggregation‐induced emission.
The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of early and locally-advanced non-small-cell lung ...cancer (NSCLC) was published in 2017, and covered the diagnosis, staging, management and treatment of both early stage I and II disease and locally-advanced stage III disease. At the ESMO Asia Meeting in November 2018, it was decided by both the ESMO and the Korean Society of Medical Oncology (KSMO) to convene a special face-to-face guidelines meeting in 2019 in Seoul. The aim was to adapt the ESMO 2017 guidelines to take into account potential differences related to ethnicity, cancer biology and standard practices associated with the treatment of locally-advanced, unresectable NSCLC in Asian patients. These guidelines represent the consensus opinions reached by those experts in the treatment of patients with lung cancer who represented the oncology societies of Korea (KSMO), China (CSCO), India (ISMPO), Japan (JSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence, and it was independent of both local current treatment practices and the treatment availability and reimbursement situations in the individual participating Asian countries.
Objective
The diagnostic yield for congenital heart defects (CHD) with routine genetic testing is around 10%–20% when considering pathogenic CNVs or aneuploidies as positive findings. This is a pilot ...study to investigate the utility of genome sequencing (GS) for prenatal diagnosis of CHD.
Methods
Genome sequencing (GS, 30X) was performed on 13 trios with CHD for which karyotyping and/or chromosomal microarray results were non‐diagnostic.
Results
Trio GS provided a diagnosis for 4/13 (30.8%) fetuses with complex CHDs and other structural anomalies. Findings included pathogenic or likely pathogenic variants in DNAH5, COL4A1, PTPN11, and KRAS. Of the nine cases without a genetic etiology by GS, we had outcome follow‐up data on eight. For five of them (60%), the parents chose to keep the pregnancy. A balanced translocation 46,XX,t(14; 22)(q32.33; q13.31)mat was detected in a trio with biallelic DNAH5 mutations, which together explained the recurrent fetal situs inversus and dextrocardia that was presumably due to de novo Phelan‐McDermid syndrome. A secondary finding of a BRCA2 variant and carrier status of HBB, USH2A, HBA1/HBA2 were detected in the cohort.
Conclusions
GS expands the diagnostic scope of mutation types over conventional testing, revealing the genetic etiology for fetal heart anomalies. Patients without a known genetic abnormality indicated by GS likely opted to keep pregnancy especially if the heart defect could be surgically repaired. We provide evidence to support the application of GS for fetuses with CHD.
Key points
What's already known about this topic?
The diagnostic yield of exome sequencing for fetuses with structural abnormalities after undiagnostic conventional testing is 20%–30%. The diagnostic yield of genome sequencing for fetal heart defects is not established.
What does this study add?
This study demonstrated that genome sequencing has a diagnostic yield of 30.5% in fetuses with congenital heart defects (CHD) and is even higher in cases with complex CHD and syndromic abnormalities.
Pulmonary stenosis with other structural anomalies is more commonly associated with a genetic diagnosis, while a molecular genetic diagnosis is less frequently achieved for isolated aortic anomalies.
Genome sequencing provided an integrated analysis of a range of mutation types and also detected additional clinically relevant genetic findings such as chromosomal structural rearrangements.
Highly selective, narcissistic self‐sorting has been observed in the one‐pot synthesis of three organometallic molecular cylinders of type M3{L‐(NHC)3}2(PF6)3 (M=Ag+, Au+; L=1,3,5‐benzene, ...triphenylamine, or 1,3,5‐triphenylbenzene) from L‐(NHC)3 and silver(I) or gold(I) ions. The molecular cylinders contain only one type of tris‐NHC ligand with no crossover products detectable. Transmetalation of the tris‐NHC ligands from Ag+ to Au+ in a one‐pot reaction with retention of the supramolecular structures is also demonstrated. High‐fidelity self‐sorting was also observed in the one‐pot reaction of benzene‐bridged tris‐NHC and tetrakis‐NHC ligands with Ag2O. This study for the first time extends narcissistic self‐sorting in metal–ligand interactions from Werner‐type complexes to organometallic derivatives.
Perfect sorting! Unique narcissistic self‐sorting has been observed in the one‐pot reaction of three different trigonal trisimidazolium salts with Ag2O. Only three cylinder‐like trinuclear complexes each bearing two identical tris‐NHC ligands were obtained from this reaction. Self‐sorting was also observed in the subsequent transmetalation of the tris‐NHC ligands from the three silver(I) complexes to give three gold(I) complexes.
Selenium (Se) acts as an essential trace element in the human body due to its unique biological functions, particularly in the oxidation-reduction system. Although several clinical trials indicated ...no significant benefit of Se in preventing cancer, researchers reported that some Se species exhibit superior anticancer properties. Therefore, a reassessment of the status of Se and Se compounds is necessary in order to provide clearer insights into the potentiality of Se in cancer prevention and therapy. In this review, we organize relevant forms of Se species based on the three main categories of Se-inorganic, organic, and Se-containing nanoparticles (SeNPs)-and overview their potential functions and applications in oncology. Here, we specifically focus on the SeNPs as they have tremendous potential in oncology and other fields. In general, to make better use of Se compounds in cancer prevention and therapy, extensive further study is still required to understand the underlying mechanisms of the Se compounds.
We aim to study the association of hyperlipidemia and statin use with COVID-19 severity. We analysed a retrospective cohort of 717 patients admitted to a tertiary centre in Singapore for COVID-19 ...infection. Clinical outcomes of interest were oxygen saturation ≤ 94% requiring supplemental oxygen, intensive-care unit (ICU) admission, invasive mechanical-ventilation and death. Patients on long term dyslipidaemia medications (statins, fibrates or ezetimibe) were considered to have dyslipidaemia. Logistic regression models were used to study the association between dyslipidaemia and clinical outcomes adjusted for age, gender and ethnicity. Statin treatment effect was determined, in a nested case-control design, through logistic treatment models with 1:3 propensity matching for age, gender and ethnicity. All statistical tests were two-sided, and statistical significance was taken as p < 0.05. One hundred fifty-six (21.8%) patients had dyslipidaemia and 97% of these were on statins. Logistic treatment models showed a lower chance of ICU admission for statin users when compared to non-statin users (ATET: Coeff (risk difference): - 0.12 (- 0.23, - 0.01); p = 0.028). There were no other significant differences in other outcomes. Statin use was independently associated with lower ICU admission. This supports current practice to continue prescription of statins in COVID-19 patients.
Post-synthetic functionalisation of commodity polymers such as polyethylene (PE) is an increasingly important strategy for giving waste plastics new 'lease-of-lives' as functional polymers. In ...particular, installing oxygenated functional groups such as alcohols and ketones is valuable due to their chemical versatility for further chemical modifications. However, this is especially challenging for PE due to its unreactive nature, and often requires hazardous and environmentally damaging chlorinated solvents owing to PE's excellent solvent resistance. Herein, we demonstrate a highly selective method to install isolated carbonyl groups on PE using only benzaldehyde and O
2
as a terminal oxidant, without the need for stoichiometric organic oxidants or any hazardous organic solvents. This process relies on the aerobic auto-oxidation of benzaldehyde to benzoic acid, generating reactive radical intermediates in the process that are responsible for both C-H activation and exclusive carbonyl formation. Our method is compatible with copper(
ii
) oxidation catalysts to enhance the extent of PE oxidation, and can also minimise the waste produced as the benzoic acid side product can be easily isolated and reused for different applications. The versatility of carbonyl-containing PEs for further chemical derivatisation offers many exciting options for transforming waste PE into diverse polymeric materials for a materials circular economy.
A solvent-free approach for the post-synthetic functionalisation of polyethylene with carbonyl groups exclusively is described using oxygen as the oxidant, with industrially-relevant benzoic acid being the sole organic side product of the reaction.
Objectives
The primary objective was to investigate the clinical presentation, hormonal dysfunction, imaging characteristics and natural history of RCCs that were managed conservatively. Secondary ...objective was to identify factors associated with cyst progression.
Methods
A retrospective review of patients with the clinical diagnosis of RCC—identified from word search from radiology reports that were followed up from January 1999 to March 2019 was performed. The demographics, clinical data, radiological features and outcomes were reviewed and analyzed.
Results
105 patients were identified with a median follow up of 6 years. 68 patients (64.8%) were managed conservatively from diagnosis till last follow up while 37 patients (35.2%) underwent surgery, with 26 operated at time of diagnosis and 11 operated upon monitoring. For patients managed conservatively from diagnosis till last follow up, incidental finding was the most common presentation. 19.1% had either one or more axes of hormonal dysfunction, with hypogonadism and hypocortisolemia being the commonest ones. Imaging features were variable. 66.2% of patients had T2W hyperintensity on MRI. Pathognomonic feature of intracystic nodule was present in only 14.7% of patients. Among the 79 patients with repeated MRI imaging (68 from conservative group and 11 from surgical group), 32.9% of patients developed cyst progression while 67.1% had either static disease or regression in size of RCC. Median time to progression of cyst was 14 months. Longer median follow up duration and presence of pituitary stalk displacement at presentation were associated with cyst progression. Only one patient developed new endocrine dysfunction.
Conclusion
2/3 of the RCCs had static disease or even regression in the size of the cyst. They rarely gave rise to additional endocrine dysfunction by adopting observant approach. Cyst progression was demonstrated in 1/3 of patients. Conservative treatment remained a reasonable treatment for patients without significant symptoms.
Anthropogenic activities have resulted in a sustained increase in atmospheric CO2 levels over the past 200 years. To mitigate this, materials capable of capturing or chemically transforming CO2 have ...received tremendous attention recently. However, porous materials such as polymeric adsorbents and metal–organic frameworks (MOFs), which have demonstrated considerable success in carbon capture and utilisation, are traditionally synthesized from non-renewable petrochemical feedstock. In line with recent trends towards a circular materials economy, there have been greater emphases on functional materials design and production from societal waste. Therefore in this Perspectives article, we highlight and discuss the possibility of using waste commodity plastics as hitherto-overlooked low-cost alternative resources for the synthesis of functional materials for CO2 capture and utilisation. This not only reduces the quantity of waste plastics disposed, but also offers a second lease-of-life to these polymers by keeping them in continuous use. Herein, we examine how the polymer structures of commodity plastics have influenced the design of the resulting carbon nanomaterials, polymeric adsorbents and MOFs for effective CO2 capture and conversion into useful chemicals, such as cyclic carbonates. With this field currently only in its infancy, we also discuss the limitations of the current work, our opinions on further exploiting the potential of waste commodity plastics for CCU applications, and the essential considerations involved in this multidisciplinary endeavour.
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