Mapping Ambiphile Reactivity Trends in the Anti-(Hetero)annulation of Non-Conjugated Alkenes via PdII /PdIV Catalysis

In this study, we systematically evaluate different ambiphilic organohalides for their ability to participate in anti-selective carbo- or heteroannulation with non-conjugated alkenyl amides under Pd^II /Pd^IV catalysis. Detailed optimization of the reaction conditions has led to protocols for synthesizing tetrahydropyridines, tetralins, pyrrolidines, and other carbo/heterocyclic cores via [n+2] (n=3-5) (hetero)annulation. Expansion of scope to otherwise unreactive ambiphilic haloketones through Pd^II /amine co-catalysis is also demonstrated. Compared to other annulation processes, this method proceeds via a distinct Pd^II /Pd^IV mechanism involving Wacker-type directed nucleopalladation. This difference results in unique reactivity and selectivity patterns, as revealed through assessment of reaction scope and competition experiments.

Atom and step economical synthesis of acyclic quaternary centers via iridium-catalyzed hydroarylative cross-coupling of 1,1-disubstituted alkenes

Quaternary benzylic centers are accessed with high atom and step economy by intermolecular Ir-catalyzed hydroarylation of non-polarized 1,1-disubstituted alkenes.

Search for Lepton Number and Flavor Violation in K^{+} and π^{0} Decays

Searches for the lepton number violating K^{+}→π^{-}μ^{+}e^{+} decay and the lepton flavor violating K^{+}→π^{+}μ^{-}e^{+} and π^{0}→μ^{-}e^{+} decays are reported using data collected by the NA62 experiment at CERN in 2017-2018. No evidence for these decays is found and upper limits of the branching ratios are obtained at 90% confidence level: B(K^{+}→π^{-}μ^{+}e^{+})<4.2×10^{-11}, B(K^{+}→π^{+}μ^{-}e^{+})<6.6×10^{-11} and B(π^{0}→μ^{-}e^{+})<3.2×10^{-10}. These results improve by 1 order of magnitude over previous results for these decay modes.

Low-Valent Tungsten Catalysis Enables Site-Selective Isomerization-Hydroboration of Unactivated Alkenes

A tungsten-catalyzed hydroboration of unactivated alkenes at distal C(sp³)-H bonds aided by native directing groups is described herein. The method is characterized by its simplicity, exquisite regio- and chemoselectivity, and wide substrate scope, offering a complementary site-selectivity pattern to other metal-catalyzed borylation reactions and chain-walking protocols.

Recent advances in palladium-catalyzed (hetero)annulation of C[double bond, length as m-dash]C bonds with ambiphilic organo(pseudo)halides

Palladium has proven to be effective in catalyzing the (hetero)annulation of C[double bond, length as m-dash]C bonds with ambiphilic organo(pseudo)halides. Through the employment of appropriate ambiphilic coupling partners, efficient annulation of a variety of allenes, 1,3-dienes, strained alkenes, styrenes, and other C[double bond, length as m-dash]C bond variants can be achieved to provide direct access to numerous useful hetero- and carbocyclic scaffolds. In this Feature Article, we summarize palladium-catalyzed (hetero)annulation methods reported since 2005 (spanning just over 15 years) and discuss outstanding challenges in this area of study.

Applications of a Novel Microangioscope for Neuroendovascular Intervention

BACKGROUND AND PURPOSE

Visualization in neuroendovascular intervention currently relies on biplanar fluoroscopy and contrast administration. With the advent of endoscopy, direct visualization of the intracranial intravascular space has become possible with microangioscopes. We analyzed the efficacy of our novel microangioscope to enable direct observation and inspection of the cerebrovasculature, complementary to a standard fluoroscopic technique.

MATERIALS AND METHODS

Iterations of microangioscopes were systematically evaluated for use in neurodiagnostics and neurointerventions in both live animal and human cadaveric models. Imaging quality, trackability, and navigability were assessed. Diagnostic procedures assessed included clot identification and differentiation, plaque identification, inspection for vessel wall injury, and assessment of stent apposition. Interventions performed included angioscope-assisted stent-retriever thrombectomy, clot aspiration, and coil embolization.

RESULTS

The microangioscope was found helpful in both diagnosis and interventions by independent evaluators. Mean ratings of the imaging quality on a 5-point scale ranged from 3.0 (clot identification) to 4.7 (Pipeline follow-up). Mean ratings for clinical utility ranged from 3.0 (aspiration thrombectomy) to 4.7 (aneurysm treatment by coil embolization and WEB device).

CONCLUSIONS

This fiber optic microangioscope can safely navigate and visualize the intravascular space in human cadaveric and in vivo animal models with satisfactory resolution. It has potential value in diagnostic and neurointerventional applications.

The stable component of maternal depressive symptoms predicts offspring emotional and behavioral symptoms: a 9-years longitudinal study

Background

Maternal sub-threshold and non-clinical depression and its possible outcomes on offspring internalizing/externalizing symptoms has received growing attention in recent years because of its significant worldwide prevalence.

Methods

Through a Latent State-Trait Analysis approach (LST), this longitudinal study aimed to identify a stable component of non-clinical maternal depression across a temporal interval of 6 years (measured through the Symptom Check-List-90/R) and to determine the effect of this component on children’s emotional and behavioral functioning (measured through the Child Behaviour Check-List) at age 12 years.

Results

LST analysis showed that maternal depressive symptoms tended to remain stable within individuals across 6 years of observation strongly contributing to children’s internalizing/externalizing and dysregulation symptoms.

Conclusions

The current longitudinal analysis of maternal and child data revealed that a stable component of maternal depressive symptoms reliably predicted a wide range of child emotional and behavioral symptoms at 12 years of age.

OP0229 GUSELKUMAB INDUCES SUSTAINED REDUCTION IN ACUTE PHASE PROTEINS AND TH17 EFFECTOR CYTOKINES IN ACTIVE PSORIATIC ARTHRITIS IN TWO PHASE-3 CLINICAL TRIALS (DISCOVER-1 AND DISCOVER-2)

Background:

Guselkumab (GUS), an IL-23 inhibitor monoclonal antibody (Mab) that specifically binds to the IL-23p19 subunit, demonstrated efficacy compared to placebo (PBO) in reducing skin and musculoskeletal signs and symptoms in patients (pts) with active psoriatic arthritis (PsA) in two phase-3 studies, DISCOVER 1 & 2.1,2Previous results from a GUS PsA Phase-2 trial3and Ustekinumab (UST, anti-IL12/23p40 MAb) PsA Phase-3 trials (PSUMMIT 1 & 2)4showed associations of baseline IL-17A, IL-17F, and CRP with baseline disease characteristics, and associations of GUS-induced cytokine reductions with clinical responses.

Objectives:

To investigate plausible cytokine expression in PsA and alterations after exposure to GUS therapy.

Methods:

In DISCOVER 1 & 2, pts were treated with GUS 100 mg at Wk 0, 4, then every 8Wks (q8w); GUS 100mg q4w; or matching PBO. 21 serum biomarkers were measured in a random subset of 300 PsA pts from the DISCOVER program at Weeks (Wks) 0, 4, & 24 and in 34 healthy controls matched for age, sex, and ethnicity. Serum proteins measured were acute phase reactants CRP & SAA (Meso Scale Discovery (MSD) Platform) and inflammatory cytokines/chemokines: Th17 effector cytokines IL-17A, IL-17F, & IL-22 (Single Molecule Counting Erenna® Immunoassay Platform) and soluble ICAM-1, soluble VCAM-1, IL-6, CXCL-8, IL-10, IL-13, IL-12p70, CCL22, IFN-γ, CCL2, CCL4, TNFα, IL-1β, IL-2, IL-4 (MSD), & YKL-40 (Quantikine Immunoassay). Serum IL-17A, IL-17B, & CRP measured in the Phase-3 PSUMMIT trials of UST for PsA4were included for comparison with GUS.

Results:

At baseline, serum levels of acute phase proteins CRP, SAA, & IL-6, and Th17-effector cytokines IL-17A & IL-17F were elevated in pts with PsA compared with healthy controls (p<0.05, geometric mean ≥ 40% higher, FIG 1). There was no significant dysregulation in the other cytokines measured in PsA pts compared to healthy controls. Baseline IL-17A, IL-17F, IL-22, & CCL22 were significantly associated with baseline psoriasis disease activity (Body Surface Area & Psoriatic Area and Severity Index, Spearman Signed Rank p<0.05, r>0.25). Baseline CRP, SAA, IL-6, & YKL40 were significantly associated with baseline joint disease (Disease Activity Score 28-CRP, Spearman p<0.05, r>0.25). Baseline SAA, IL-6, IL-17A, & IL-17F were higher in pts with prior TNF inhibitor exposure than without (p<0.05, geometric mean ≥ 40% higher), although pts with PsA both with and without prior TNF inhibitor had higher levels than the healthy control set.

GUS treatment resulted in decreases in serum CRP, SAA, IL-6, IL-17A, IL-17F, & IL-22 that were significantly greater than PBO as early as Week 4 (FIG 1). These protein levels continued to decrease through Wk 24 in GUS-treated pts with both dosing regimens (p<0.05, geometric mean decrease from baseline ≥ 33%). Further, Wk 24 IL-17A & IL-17F levels for pts treated with either dose of GUS were not significantly different from healthy controls, suggesting a normalization of peripheral effector cytokines associated with the IL-23/Th17 axis following treatment with GUS. Effects on IL-17A/IL-17F were greater in GUS treated pts than UST treated pts, while CRP levels were similar in both programs (FIG 2).

Conclusion:

Comprising a strong pharmacodynamic effect, GUS treatment reduced serum protein levels of acute phase and Th17-effector cytokines (whose elevations at baseline were associated with PsA disease characteristics) and achieved comparable levels to those in healthy controls. In pts with PsA, reductions of IL-17A and IL-17F by GUS were of greater magnitude than those by UST.

References:

[1]Deodhar et al. ACR 2019, abs #807. Arth Rheumatol. 2019;71 S10: 1386

[2]Mease et al. ACR 2019, abs #L13. Arth Rheumatol. 2019;71 S10:5247

[3]Siebert et al. EULAR 2019, abs #479. Ann Rheum Dis. 2019;78 S2:293

[4]Siebert et al. Arth Rheumatol. 2019;71:1660

Acknowledgments:

None

Disclosure of Interests:

Stefan Siebert Grant/research support from: BMS, Boehringer Ingelheim, Celgene, GlaxoSmithKline, Janssen, Novartis, Pfizer, UCB, Consultant of: AbbVie, Boehringer Ingelheim, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, Celgene, Janssen, Novartis, Iain McInnes Grant/research support from: Bristol-Myers Squibb, Celgene, Eli Lilly and Company, Janssen, and UCB, Consultant of: AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly and Company, Gilead, Janssen, Novartis, Pfizer, and UCB, Matthew J Loza Employee of: Janssen Research & Development, LLC, Keying Ma Employee of: Janssen Research & Development, LLC, Karen Leander, Employee of: Janssen Research & Development, LLC, Vani Lakshminarayanan Employee of: Janssen Research & Development, LLC, Carol Franks Employee of: Janssen Research & Development, LLC, Philip Cooper Employee of: Janssen Research & Development, LLC, Kristen Sweet Employee of: Janssen Research & Development, LLC

Iridium-Catalyzed α-Selective Arylation of Styrenes by Dual C-H Functionalization

An Ir^I‐system modified with a ferrocene derived bisphosphine ligand promotes α‐selective arylation of styrenes by dual C−H functionalization. These studies offer a regioisomeric alternative to the Pd‐catalyzed Fujiwara–Moritani reaction.

Long-Term Stability Studies on the WHO IRP for Thromboplastin (Human Plain BCT/253)

Long-term stability studies on the WHO second primary International Reference Preparation (IRP) for thromboplastin (human plain BCT/253) stored at ™20° C have been conducted for ten years.

Three centres took part in the exercise using frozen normal and coumarinised plasma samples which were tested throughout. There has been no measurable change in the prothrombin time performance of the human plain IRP over the ten-year period. It can therefore be concluded that new IRP may continue to be calibrated against this preparation in accord with WHO recommendations.

NA62 and NA48/2 results on search for Heavy Neutral Leptons

In this paper we present new results on upper limits for the search of Heavy Neutral Leptons (HNL) with data collected by NA48/2 (2003-2004), NA62-RK (2007) and NA62 (2015) CERN experiments. The data collected with different trigger configuration allow to search for both long and short living heavy neutrinos in the mass range below the kaon mass. In addition the status of the search for K+ → π+vv with the NA62 detector will be briefly presented.

Diversification of ortho-Fused Cycloocta-2,5-dien-1-one Cores and Eight- to Six-Ring Conversion by σ Bond C-C Cleavage

Sequential treatment of 2-C6 H4 Br(CHO) with LiC≡CR(1) (R(1) =SiMe3 , tBu), nBuLi, CuBr⋅SMe2 and HC≡CCHClR(2) [R(2) =Ph, 4-CF3 Ph, 3-CNPh, 4-(MeO2 C)Ph] at -50 °C leads to formation of an intermediate carbanion (Z)-1,2-C6 H4 {CA (=O)C≡CB R(1) }{CH=CH(CH(-) )R(2) } (4). Low temperatures (-50 °C) favour attack at CB leading to kinetic formation of 6,8-bicycles containing non-classical C-carbanion enolates (5). Higher temperatures (-10 °C to ambient) and electron-deficient R(2) favour retro σ-bond C-C cleavage regenerating 4, which subsequently closes on CA providing 6,6-bicyclic alkoxides (6). Computational modelling (CBS-QB3) indicated that both pathways are viable and of similar energies. Reaction of 6 with H(+) gave 1,2-dihydronaphthalen-1-ols, or under dehydrating conditions, 2-aryl-1-alkynylnaphthlenes. Enolates 5 react in situ with: H2 O, D2 O, I2 , allylbromide, S2 Me2 , CO2 and lead to the expected C-E derivatives (E=H, D, I, allyl, SMe, CO2 H) in 49-64 % yield directly from intermediate 5. The parents (E=H; R(1) =SiMe3 , tBu; R(2) =Ph) are versatile starting materials for NaBH4 and Grignard C=O additions, desilylation (when R(1) =SiMe) and oxime formation. The latter allows formation of 6,9-bicyclics via Beckmann rearrangement. The 6,8-ring iodides are suitable Suzuki precursors for Pd-catalysed C-C coupling (81-87 %), whereas the carboxylic acids readily form amides under T3P® conditions (71-95 %).

Development of an automated, real time surveillance tool for predicting readmissions at a community hospital

BACKGROUND

The Centers for Medicare and Medicaid Services' Readmissions Reduction Program adjusts payments to hospitals based on 30-day readmission rates for patients with acute myocardial infarction, heart failure, and pneumonia. This holds hospitals accountable for a complex phenomenon about which there is little evidence regarding effective interventions. Further study may benefit from a method for efficiently and inexpensively identifying patients at risk of readmission. Several models have been developed to assess this risk, many of which may not translate to a U.S. community hospital setting.

OBJECTIVE

To develop a real-time, automated tool to stratify risk of 30-day readmission at a semirural community hospital.

METHODS

A derivation cohort was created by extracting demographic and clinical variables from the data repository for adult discharges from calendar year 2010. Multivariate logistic regression identified variables that were significantly associated with 30-day hospital readmission. Those variables were incorporated into a formula to produce a Risk of Readmission Score (RRS). A validation cohort from 2011 assessed the predictive value of the RRS. A SQL stored procedure was created to calculate the RRS for any patient and publish its value, along with an estimate of readmission risk and other factors, to a secure intranet site.

RESULTS

Eleven variables were significantly associated with readmission in the multivariate analysis of each cohort. The RRS had an area under the receiver operating characteristic curve (c-statistic) of 0.74 (95% CI 0.73-0.75) in the derivation cohort and 0.70 (95% CI 0.69-0.71) in the validation cohort.

CONCLUSION

Clinical and administrative data available in a typical community hospital database can be used to create a validated, predictive scoring system that automatically assigns a probability of 30-day readmission to hospitalized patients. This does not require manual data extraction or manipulation and uses commonly available systems. Additional study is needed to refine and confirm the findings.

Parenting stress of caregivers of young children who are HIV Positive

OBJECTIVE

Paediatric HIV remains a major challenge in Sub-Saharan Africa. Paediatric HIV is a multi-generational disorder with far-reaching implications for the whole family. Parenting stress in caregivers of HIV infected children has been studied in developed countries but never in South Africa. The aim of this study was to determine the extent of parenting stress in caregivers of children infected with HIV in South Africa. Further objectives were to monitor the levels of stress over one year after caregivers started attending a paediatric HIV clinic and to ascertain what factors were predictive of a decrease in parenting stress over that time.

METHOD

One hundred and twenty two caregiver and children dyads were recruited into this study. Caregivers completed the Parenting Stress Index/ Short form at baseline and after six and 12 months. Demographic information was collected and the children's heights, weights and CD4 counts were recorded at each visit.

RESULTS

The families that participated in this study came from very poor socio-economic backgrounds. Eighty five percent of the children were still being cared for by their biological mothers. The parenting stress levels of the caregivers in this study were extremely high at baseline. Although the parenting stress levels did come down significantly over the study period (p< 0.001) they remained high and warrant further investigation and management. A better level of education, better housing facilities and fewer adults living in the household were the three most important factors predicting a decrease in parenting stress over a one year period.

CONCLUSION

Parenting stress of caregivers of young children infected with HIV is extremely high and warrants further investigation and long term management.

Purpura fulminans: recognition, diagnosis and management

Purpura fulminans (PF) is a haematological emergency in which there is skin necrosis and disseminated intravascular coagulation. This may progress rapidly to multi-organ failure caused by thrombotic occlusion of small and medium-sized blood vessels. PF may complicate severe sepsis or may occur as an autoimmune response to otherwise benign childhood infections. PF may also be the presenting symptom of severe heritable deficiency of the natural anticoagulants protein C or protein S. Early recognition and treatment of PF is essential to reduce mortality and to prevent major long-term health sequelae. However, management strategies require accurate identification of the underlying cause. This review focuses on the clinical features, differential diagnosis and laboratory features of the range of PF disorders and includes expert consensus opinion about immediate and on-going management.

Initial experience with a rapid access blackouts triage clinic

Transient loss of consciousness (T-LOC), or blackout, is common in acute medicine. Clinical skills are not done well, with at least 74,000 patients misdiagnosed and mistreated for epilepsy in England alone. The aim of this study was to provide a rapid, structured assessment and an electrocardiogram (ECG) for patients with blackouts, aiming to identify high risk, reduce misdiagnoses, reduce hospital admission rates for low-risk patients, diagnose and treat where appropriate, and also provide onward specialist referral. The majority of patients had syncope, and very few had epilepsy. A high proportion had an abnormal ECG. A specialist-nurse-led rapid access blackouts triage clinic (RABTC) provided rapid effective triage for risk, a comprehensive assessment format, direct treatment for many patients, and otherwise a prompt appropriate onward referral. Rapid assessment through a RABTC reduced re-admissions with blackouts. Widespread use of the web-based blackouts tool could provide the NHS with a performance map. The U.K. has low rates of pacing compared to Western Europe, which RABTCs might help correct. The RABTC sits between first responders and specialist referral, providing clinical assessment and ECG in all cases, and referral where appropriate.

Freeform surface filtering using the diffusion equation

The measurement of texture for geometric surfaces is well established for surfaces that are of a planar (Euclidean) nature. Gaussian filtering is the fundamental base for scale-limited surfaces used in surface texture, but cannot be applied to non-Euclidean surfaces without distortion of the results. A link exists between Gaussian filtering and solutions of the PDE that models linear isotropic diffusion. In particular, an analytical solution of this diffusion equation over a planar region at a time t is given by the continuous convolution of the initial distribution of the diffused quantity with a Gaussian function of standard deviation . A practical implementation of the standard Gaussian filter on sampled data can be viewed as a discretization of this process. On a non-Euclidean surface, the diffusion equation is formulated by using the Laplace–Beltrami operator. Using this generalization, a method of Gaussian filtering for freeform surface data is proposed by solving the diffusion equation for approximation residuals defined on a freeform least-squares approximation of the measurement surface data. Results of the application of these methods to simulated and experimental data are presented.

Maize nuclear background regulates the synthesis of a 22-kDa polypeptide in Zea luxurians mitochondria

When cytoplasm of the teosinte Zea luxurians is introduced into certain maize inbred nuclear backgrounds, the pattern of protein synthesis in the teosinte mitochondria is altered. Teosinte mitochondria purified from plants possessing a maize A619 nuclear background (Z.l.-A619 plants) synthesize a novel 22-kDa polypeptide that is associated exclusively with the membrane fraction of the organelle. Mitochondria from plants possessing a W23 nuclear background do not synthesize this protein. The F(1) hybrids Z.l.-A619 x W23 and Z.l.-W23 x A619 do not synthesize the protein. However, synthesis of the polypeptide was observed in 14 of 21 individual progeny from the backcross of the F(1) hybrid Z.l.-A619 x W23 to the pollen parent A619. These data suggest that a single nuclear gene controls the synthesis of the 22-kDa protein in mitochondria, with the recessive allele of the gene allowing expression of the polypeptide. Mitochondria from the F(1) hybrid Z.l.-A619 x Mo17 synthesize the 22-kDa protein, whereas mitochondria from Z.l.-A619 x B73 do not. Data from these outcrosses demonstrate that other maize lines also possess nuclear genes capable of regulating the synthesis of the 22-kDa Zea luxurians mitochondrial protein.

International variations in associations of allergic markers and diseases in children: ISAAC Phase Two

BACKGROUND

Circulating allergen-specific IgE (sIgE) and skin prick tests (SPT) are used to define atopy. Downregulation of local inflammatory responsiveness has been proposed to explain a low prevalence of positive SPTs in less affluent countries. We analysed the association between SPTs, total and allergen-specific IgE and their relationships to allergic symptoms in centres with diverse living conditions.

METHODS

Cross-sectional studies of stratified random samples of 8 to 12-year-old children (n = 7461) used the standardized methodology of Phase Two of the International Study of Asthma and Allergies in Childhood (ISAAC). Symptoms of asthma, rhinitis and eczema were ascertained by parental questionnaires. Skin examination, hypertonic saline bronchial challenge, six aeroallergen SPTs and measurements of serum total IgE and sIgE were performed.

RESULTS

In nonaffluent countries, a higher proportion of children with positive SPT had no detectable sIgE (range 37-61%) than in affluent countries (0-37%). Total serum IgE was associated with all disease outcomes among children with both positive SPT and sIgE (P < 0.001), but only with self-reported eczema in children with negative SPTs and negative sIgE.

CONCLUSIONS

The international pattern of discordance between SPT and sIgE results did not support the downregulation hypothesis. Among children with no evidence of sensitization to common aeroallergens, increased total IgE contributes little to the risk of wheeze and rhinitis in the general population but may play a role in eczema.