Nonadiabatic coupling reduces the activation energy in thermally activated delayed fluorescence

The activation energy of thermally activated delayed fluorescence can be reduced by nonadiabatic coupling.

Dissection of major depressive disorder using polygenic risk scores for schizophrenia in two independent cohorts

Major depressive disorder (MDD) is known for its substantial clinical and suspected causal heterogeneity. It is characterized by low mood, psychomotor slowing and increased levels of the personality trait neuroticism; factors also associated with schizophrenia (SCZ). It is possible that some cases of MDD may have a substantial genetic loading for SCZ. The presence of SCZ-like MDD subgroups would be indicated by an interaction between MDD status and polygenic risk of SCZ on cognitive, personality and mood measures. Here, we hypothesized that higher SCZ polygenic risk would define larger MDD case-control differences in cognitive ability, and smaller differences in distress and neuroticism. Polygenic risk scores (PRSs) for SCZ and their association with cognitive variables, neuroticism, mood and psychological distress were estimated in a large population-based cohort (Generation Scotland: Scottish Family Health Study, GS:SFHS). The individuals were divided into those with, and without, depression (n=2587 and n=16 764, respectively) to test for the interactions between MDD status and schizophrenia risk. Replication was sought in UK Biobank (UKB; n=6049 and n=27 476 cases and controls, respectively). In both the cohorts, we found significant interactions between SCZ-PRS and MDD status for measures of psychological distress (βGS=-0.04, PGS=0.014 and βUKB=-0.09, PUKB⩽0.001 for GS:SFHS and UKB, respectively) and neuroticism (βGS=-0.04, PGS=0.002 and βUKB=-0.06, PUKB=0.023). In both the cohorts, there was a reduction of case-control differences on a background of higher genetic risk of SCZ. These findings suggest that depression on a background of high genetic risk for SCZ may show attenuated associations with distress and neuroticism. This may represent a causally distinct form of MDD more closely related to SCZ.

Multiple myeloma causes clonal T-cell immunosenescence: identification of potential novel targets for promoting tumour immunity and implications for checkpoint blockade

Tumour-induced dysfunction of cytotoxic T cells in patients with multiple myeloma (MM) may contribute to immune escape and be responsible for the lack of therapeutic efficacy of immune checkpoint blockade. We therefore investigated dysfunctional clonal T cells in MM and demonstrated immunosenescence but not exhaustion as a predominant feature. T-cell clones were detected in 75% of MM patients and their prognostic significance was revalidated in a new post-immunomodulatory drug cohort. The cells exhibited a senescent secretory effector phenotype: KLRG-1+/CD57+/CD160+/CD28-. Normal-for-age telomere lengths indicate that senescence is telomere independent and potentially reversible. p38-mitogen-activated protein kinase, p16 and p21 signalling pathways known to induce senescence were not elevated. Telomerase activity was found to be elevated and this may explain how normal telomere lengths are maintained in senescent cells. T-cell receptor signalling checkpoints were normal but elevated SMAD levels associated with T-cell inactivation were detected and may provide a potential target for the reversal of clonal T-cell dysfunction in MM. Low programmed death 1 and cytotoxic T-lymphocyte-associated antigen 4 expression detected on T-cell clones infers that these cells are not exhausted but suggests that there would be a suboptimal response to immune checkpoint blockade in MM. Our data suggest that other immunostimulatory strategies are required in MM.

Longitudinal copy number, whole exome and targeted deep sequencing of 'good risk' IGHV-mutated CLL patients with progressive disease

The biological features of IGHV-M chronic lymphocytic leukemia responsible for disease progression are still poorly understood. We undertook a longitudinal study close to diagnosis, pre-treatment and post relapse in 13 patients presenting with cMBL or Stage A disease and good-risk biomarkers (IGHV-M genes, no del(17p) or del(11q) and low CD38 expression) who nevertheless developed progressive disease, of whom 10 have required therapy. Using cytogenetics, fluorescence in situ hybridisation, genome-wide DNA methylation and copy number analysis together with whole exome, targeted deep- and Sanger sequencing at diagnosis, we identified mutations in established chronic lymphocytic leukemia driver genes in nine patients (69%), non-coding mutations (PAX5 enhancer region) in three patients and genomic complexity in two patients. Branching evolutionary trajectories predominated (n=9/13), revealing intra-tumoural epi- and genetic heterogeneity and sub-clonal competition before therapy. Of the patients subsequently requiring treatment, two had sub-clonal TP53 mutations that would not be detected by standard methodologies, three qualified for the very-low-risk category defined by integrated mutational and cytogenetic analysis and yet had established or putative driver mutations and one patient developed progressive, therapy-refractory disease associated with the emergence of an IGHV-U clone. These data suggest that extended genomic and immunogenetic screening may have clinical utility in patients with apparent good-risk disease.

Management of systemic AL amyloidosis: recommendations of the Myeloma Foundation of Australia Medical and Scientific Advisory Group

Systemic AL amyloidosis is a plasma cell dyscrasia with a characteristic clinical phenotype caused by multi-organ deposition of an amyloidogenic monoclonal protein. This condition poses a unique management challenge due to the complexity of the clinical presentation and the narrow therapeutic window of available therapies. Improved appreciation of the need for risk stratification, standardised use of sensitive laboratory testing for monitoring disease response, vigilant supportive care and the availability of newer agents with more favourable toxicity profiles have contributed to the improvement in treatment-related mortality and overall survival seen over the past decade. Nonetheless, with respect to the optimal management approach, there is a paucity of high-level clinical evidence due to the rarity of the disease, and enrollment in clinical trials is still the preferred approach where available. This review will summarise the Clinical Practice Guidelines on the Management of Systemic Light Chain (AL) Amyloidosis recently prepared by the Medical Scientific Advisory Group of the Myeloma Foundation of Australia. It is hoped that these guidelines will assist clinicians in better understanding and optimising the management of this difficult disease.

Chemical pretreatment of combined sewer overflows for improved UV disinfection

The aim of this research was to better understand chemical pre-treatment of combined sewer overflows (CSOs) for subsequent ultraviolet (UV) disinfection. Approximately 200 jar tests were completed. Alum (Al2(S04)3·12H2O) resulted in a higher UV light transmission (UVT), and equivalent total suspended solids (TSS) removal, than ferric chloride (FeCl3). An alum dose of 20 mg/L increased the UVT of the raw CSO from 30 to 60% after settling. The addition of 100 mg/L of alum maximized UVT reaching approximately 85%. Flocculation did not increase UVT. However, it did improve the removal of TSS. Cationic polymers worked quickly compared with metal coagulants, but only reached a UVT of 60%. A high positive charge density on the polymer improved the removal of turbidity when compared with low charge, but did not affect UVT. If the goal is to maximise UVT, a very high alum dose may be preferred. If the goal is to minimize coagulant dose with moderate UV performance, cationic polymer at approximately 3 mg/L is recommended.

A rare penetrant TIMP3 mutation confers relatively late onset choroidal neovascularisation which can mimic age-related macular degeneration

PURPOSE

To perform a genotype-phenotype correlation for three patients heterozygous for a missense mutation in the tissue inhibitor of metalloproteinase 3 (TIMP3) gene.

METHODS

Retrospective, observational case series. The medical records and photographs were reviewed for three patients diagnosed at the time with neovascular age-related macular degeneration (AMD). All were later found to carry a predicted C113G mutation in the TIMP3 gene, other known mutations in which are associated with Sorsby's fundus dystrophy.

RESULTS

All three patients developed drusen and bilateral choroidal neovascularisation with subsequent disciform scarring and atrophy. Visual acuity rapidly deteriorated to <6/60 in both eyes. The age of onset varied from 56 to 64 years and the interval to contralateral eye involvement varied from 4 to 6 years. Two of the three patients had a family history of AMD. All three patients were heterozygous for the C113G nucleotide change, resulting in a Ser38Cys change at the N terminus of the TIMP3 protein.

CONCLUSION

This case series suggests the C113G TIMP3 variant may represent a novel highly penetrant mutation causing choroidal neovascularisation of relatively late onset for Sorsby's fundus dystrophy, mimicking early onset AMD.

Evaluating digital diabetic retinopathy screening in people aged 90 years and over

PURPOSE

To evaluate the effectiveness of digital diabetic retinopathy screening in patients aged 90 years and over.

METHODS

This is a retrospective analysis of 200 randomly selected patients eligible for diabetic retinopathy screening aged 90 years and over within the Birmingham, Solihull, and Black Country Screening Programme.

RESULTS

One hundred and seventy-nine (90%) patients attended screening at least once.

OUTCOMES

133 (74%) annual screening after their first screen, of whom 59% had no detectable diabetic retinopathy; 38 (21%) were referred for ophthalmology clinical assessment-36 for nondiabetic retinopathy reasons and two for diabetic maculopathy. Cataract accounted for 50% of all referrals for ophthalmology clinical assessment. Of the 133 patients placed on annual screening, 93 (70%) were screened at least once more. In terms of level of diabetic retinopathy, assessability or other ocular pathologies, 8 improved, 51 remained stable, and 31 deteriorated. Of the latter, 19 patients were referred for ophthalmology clinical assessment; none of these for diabetic retinopathy.

CONCLUSIONS

Screening provides opportunistic identification of important nondiabetic retinopathy eye conditions. However, in view of the low identification rate of sight-threatening diabetic retinopathy in patients aged 90 years and over, and the current mission statement of the NHS Diabetic Eye Screening Programme, systematic annual diabetic retinopathy screening may not be justified in this age group of patients, but rather be performed in optometric practice.

Defining response to anti-VEGF therapies in neovascular AMD

The introduction of anti-vascular endothelial growth factor (anti-VEGF) has made significant impact on the reduction of the visual loss due to neovascular age-related macular degeneration (n-AMD). There are significant inter-individual differences in response to an anti-VEGF agent, made more complex by the availability of multiple anti-VEGF agents with different molecular configurations. The response to anti-VEGF therapy have been found to be dependent on a variety of factors including patient's age, lesion characteristics, lesion duration, baseline visual acuity (VA) and the presence of particular genotype risk alleles. Furthermore, a proportion of eyes with n-AMD show a decline in acuity or morphology, despite therapy or require very frequent re-treatment. There is currently no consensus as to how to classify optimal response, or lack of it, with these therapies. There is, in particular, confusion over terms such as 'responder status' after treatment for n-AMD, 'tachyphylaxis' and 'recalcitrant' n-AMD. This document aims to provide a consensus on definition/categorisation of the response of n-AMD to anti-VEGF therapies and on the time points at which response to treatment should be determined. Primary response is best determined at 1 month following the last initiation dose, while maintained treatment (secondary) response is determined any time after the 4th visit. In a particular eye, secondary responses do not mirror and cannot be predicted from that in the primary phase. Morphological and functional responses to anti-VEGF treatments, do not necessarily correlate, and may be dissociated in an individual eye. Furthermore, there is a ceiling effect that can negate the currently used functional metrics such as >5 letters improvement when the baseline VA is good (ETDRS>70 letters). It is therefore important to use a combination of both the parameters in determining the response.The following are proposed definitions: optimal (good) response is defined as when there is resolution of fluid (intraretinal fluid; IRF, subretinal fluid; SRF and retinal thickening), and/or improvement of >5 letters, subject to the ceiling effect of good starting VA. Poor response is defined as <25% reduction from the baseline in the central retinal thickness (CRT), with persistent or new IRF, SRF or minimal or change in VA (that is, change in VA of 0+4 letters). Non-response is defined as an increase in fluid (IRF, SRF and CRT), or increasing haemorrhage compared with the baseline and/or loss of >5 letters compared with the baseline or best corrected vision subsequently. Poor or non-response to anti-VEGF may be due to clinical factors including suboptimal dosing than that required by a particular patient, increased dosing intervals, treatment initiation when disease is already at an advanced or chronic stage), cellular mechanisms, lesion type, genetic variation and potential tachyphylaxis); non-clinical factors including poor access to clinics or delayed appointments may also result in poor treatment outcomes. In eyes classified as good responders, treatment should be continued with the same agent when disease activity is present or reactivation occurs following temporary dose holding. In eyes that show partial response, treatment may be continued, although re-evaluation with further imaging may be required to exclude confounding factors. Where there is persistent, unchanging accumulated fluid following three consecutive injections at monthly intervals, treatment may be withheld temporarily, but recommenced with the same or alternative anti-VEGF if the fluid subsequently increases (lesion considered active). Poor or non-response to anti-VEGF treatments requires re-evaluation of diagnosis and if necessary switch to alternative therapies including other anti-VEGF agents and/or with photodynamic therapy (PDT). Idiopathic polypoidal choroidopathy may require treatment with PDT monotherapy or combination with anti-VEGF. A committee comprised of retinal specialists with experience of managing patients with n-AMD similar to that which developed the Royal College of Ophthalmologists Guidelines to Ranibizumab was assembled. Individual aspects of the guidelines were proposed by the committee lead (WMA) based on relevant reference to published evidence base following a search of Medline and circulated to all committee members for discussion before approval or modification. Each draft was modified according to feedback from committee members until unanimous approval was obtained in the final draft. A system for categorising the range of responsiveness of n-AMD lesions to anti-VEGF therapy is proposed. The proposal is based primarily on morphological criteria but functional criteria have been included. Recommendations have been made on when to consider discontinuation of therapy either because of success or futility. These guidelines should help clinical decision-making and may prevent over and/or undertreatment with anti-VEGF therapy.

Clinical reasoning: novel GLUT1-DS mutation: refractory seizures and ataxia

Intractable epilepsy is a common diagnosis among child neurology practitioners with medical management remaining unsatisfactory in many cases. GLUT1 deficiency syndrome (GLUT1-DS) is a disorder that should be considered in such situations. Evaluation by comparing serum to CSF glucose levels is a fast and relatively easy test, with hypoglycorrhachia being highly suggestive of GLUT1-DS. Furthermore, treatment with the ketogenic diet is well-established and can result in significant improvement in quality of life for these patients. The following case report outlines the presentation of one such patient and highlights common features that can be seen with GLUT1-DS. Of interest, she was found to have a spontaneous, novel mutation that has not been reported previously. Her case allows us to expand on the present literature and demonstrate the improvements that can be seen in a child with appropriate treatment.

A convenient synthetic route to sulfonimidamides from sulfonamides

This one-pot synthesis of sulfonimidamides provides a new structural modification approach for sulfonamides, and might benefit drug discovery and development in the future.