Association between cerebral blood flow changes and blood-brain barrier compromise in spontaneous intracerebral haemorrhage

AIM

To quantitatively evaluate blood-brain barrier (BBB) permeability in the perihaematomal region of spontaneous intracerebral haemorrhage (ICH) and investigate the association between the alterations in cerebral blood flow and BBB permeability around the haematoma.

MATERIALS AND METHODS

Spontaneous ICH patients underwent unenhanced computed tomography (CT) and CT perfusion (CTP) simultaneously. Haematoma volume was measured on CT. The values of cerebral haemodynamic parameters including cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and permeability-surface area product (PS) were measured in the perihaematomal region and the contralateral mirror region, and then relative values were calculated for statistical analysis. Linear regression was used to evaluate associations between BBB permeability and variables.

RESULTS

A total of 87 ICH patients were included in this study. The focally elevated BBB permeability was observed in the perihaematomal region in ICH patients. Linear regression showed that reduced rCBF (β = -0.379, p=0.001) and increased rCBV (β = 0.412, p=0.000) correlated independently with increased relative PS (rPS) value in deep ICH, while only increased rCBV (β = 0.423, p=0.071) correlated to increased rPS value in patients with lobar ICH.

CONCLUSIONS

BBB permeability is focally elevated in the region around the haematoma. Cerebral haemodynamic alterations are associated with increased BBB permeability. Cerebral hypoperfusion may aggravate BBB compromise, and a compensatory increase in CBV may lead to reperfusion injury on BBB.

Experimental Evidence of t_{2g} Electron-Gas Rashba Interaction Induced by Asymmetric Orbital Hybridization

We report the control of Rashba spin-orbit interaction by tuning asymmetric hybridization between Ti orbitals at the LaAlO_{3}/SrTiO_{3} interface. This asymmetric orbital hybridization is modulated by introducing a LaFeO_{3} layer between LaAlO_{3} and SrTiO_{3}, which alters the Ti-O lattice polarization and traps interfacial charge carriers, resulting in a large Rashba spin-orbit effect at the interface in the absence of an external bias. This observation is verified through high-resolution electron microscopy, magnetotransport and first-principles calculations. Our results open hitherto unexplored avenues of controlling Rashba interaction to design next-generation spin orbitronics.

Measured proton electromagnetic structure deviates from theoretical predictions

The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state. A fundamental property of the proton involves the response of the system to an external electromagnetic field. It is characterized by the electromagnetic polarizabilities¹ that describe how easily the charge and magnetization distributions inside the system are distorted by the electromagnetic field. Moreover, the generalized polarizabilities² map out the resulting deformation of the densities in a proton subject to an electromagnetic field. They disclose essential information about the underlying system dynamics and provide a key for decoding the proton structure in terms of the theory of the strong interaction that binds its elementary quark and gluon constituents. Of particular interest is a puzzle in the electric generalized polarizability of the proton that remains unresolved for two decades². Here we report measurements of the proton's electromagnetic generalized polarizabilities at low four-momentum transfer squared. We show evidence of an anomaly to the behaviour of the proton's electric generalized polarizability that contradicts the predictions of nuclear theory and derive its signature in the spatial distribution of the induced polarization in the proton. The reported measurements suggest the presence of a new, not-yet-understood dynamical mechanism in the proton and present notable challenges to the nuclear theory.

Diagnostic performance of angiography-derived index of microvascular resistance: a systematic review and pooled meta-analysis

Background

The index of microvascular resistance (IMR) is an established measurement of coronary microcirculation status. However, it has not been widely incorporated into routine practice due to need for intracoronary instrumentation (pressure wire) and hyperaemic agents. Several angiography-derived quantitative flow ratio-based indexes of microvascular resistance (angio-IMR) have been proposed rekindling the interest for the assessment and management of microvascular disease.

Purpose

To review the overall diagnostic accuracy of angio-IMR against wire based IMR.

Methods

A systematic review of the literature was performed and studies comparing angio-IMR with wire based IMR were included. Individual data was extracted using semi-automatic digitalization. Correlation of angio-IMR with IMR and its diagnostic performance against IMR were analysed.

Results

Six studies directly comparing angio-IMR with IMR were included. Data extraction rate was 85.1% (582/684 vessels). There was a linear correlation between angio-IMR and IMR (β=0.483, R square=0.298) (Figure 1A). Pooled sensitivity was 77%, specificity was 66%, positive predictive value was 65%, negative predictive value was 78%, and accuracy was 71.0%. Pooled area under receiver operator curve of angio-IMR for predicting IMR diagnosed coronary microvascular disease was 0.754 (95% confidential interval 0.715 to 0.793) (Figure 1B). Similar diagnostic performance was observed in subgroups of patients with or without ST-segment elevation myocardial infarction.

Conclusions

Currently available angio-IMR showed a clearly useful discrimination and diagnostic performance against the standard of wire based IMR.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): China Scholarship Council

Lower risk of gout in sodium glucose cotransporter 2 (SGLT2) inhibitors versus dipeptidyl peptidase-4 (DPP4) inhibitors in type-2 diabetes patients: a propensity score-matched study

Background

The effects of sodium-glucose cotransporter 2 inhibitors (SGLT2I) versus dipeptidyl peptidase-4 inhibitors (DPP4I) on the risk of new gout diagnosis have not been explored. This study aims to compare the effects of SGLT2I against DPP4I on gout risks in a Chinese population.

Methods

This was a retrospective population-based cohort study of patients with type-2 diabetes mellitus treated with SGLT2I or DPP4I between January 1st, 2015 and December 31st, 2020 in Hong Kong. The study outcomes are new-onset gout and all-cause mortality. Propensity score matching (1:1 ratio) between SGLT2I and DPP4I was performed. Univariable and multivariable Cox regression analysis models were conducted. Competing risks models and multiple approaches based on the propensity score were applied.

Patients

This study included 60996 patients (median age: 62.3 years old, 54.96% males; SGLTI group: n=21690; DPP4I group: n=39306).

Results

In the matched cohort, 1096 developed gout (IR: 2.52%) and 2195 died (IR: 5.05%). Univariable Cox regression showed that SGLT2I use was associated with lower risks of new diagnosis of gout (hazard ratio [HR]: 0.34; 95% confidence interval [CI]: 0.30–0.39; P-value<0.0001) and all-cause mortality (HR: 0.35; 95% CI: 0.32–0.39; P-value<0.0001) compared to DPP4I. The associated remained for both new diagnosis of gout (HR: 0.46; 95% CI: 0.37–0.57; P-value<0.0001) and all-cause mortality (HR: 0.38; 95% CI: 0.33–0.44; P-value<0.0001) after adjusting for significant demographics, past comorbidities, and non-SGLT2I/DPP4I medications. The risks of gout were lowered in each types of SGLT2I. The results were consistent on competing risk and other propensity score approaches analyses.

Conclusions

SGLT2I use was associated with lower risks of new gout diagnosis compared to DPP4I use.

Funding Acknowledgement

Type of funding sources: None.

Impact of cardiovascular events on primary and hospital care costs: findings from UK Biobank study

Background

Need for primary and secondary healthcare increases following cardiovascular disease (CVD) events but there is no data on comparative increases in costs.

Purpose

To estimate annual primary care and hospital inpatient costs associated with key CVD and other adverse events using the UK Biobank (UKB) individual participant data.

Methods

UKB participants with linked primary care data (192,983 participants) or hospital inpatient episodes data (all 501,807 participants) contributed data to this study. The three categories of primary care services (patient consultations, diagnostic and monitoring tests, prescription medications), and hospital episodes were costed (2020 UK£) using the NHS England reference costs. Annual primary care costs and, separately, annual hospital inpatient costs were modelled as functions of participant characteristics at entry (socio-demographic, clinical, prior diseases) and time-updated first occurrences of myocardial infarction, stroke, coronary revascularization, incident cancer, incident diabetes, vascular death and non-vascular death during follow-up (p-value <0.01 in stepwise covariate selection). One-part generalized linear regression model (GLM) with Poisson distribution and identity link function was used for primary care costs, and two-part model was used for inpatient costs (part 1: logistic regression models probability of incurring costs; part 2: GLM with Poisson distribution and identity link function models costs conditional on incurring any). Separate models were fitted among participants with and without previous CVD at entry into UKB.

Results

Most adverse events were associated with excess primary care and hospital inpatient costs. Compared to people without previous CVD, people with previous CVD had on average larger excess primary care and hospital inpatient costs in years with myocardial infarction, stroke and vascular death; but similar excess costs in years with other events. Among both people without and with previous CVD, the excess annual primary care costs were less than 7% of the excess annual hospital inpatient costs for vascular events (Table). However, following diabetes diagnosis the excess annual primary care costs were higher than the excess annual hospital inpatient costs (Table).

Conclusions

These excess primary and hospital care costs associated with CVD events could inform assessments of interventions and policies to reduce CVD risks in UK.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme, UK Medical Research Council (MRC), British Heart Foundation

Predictive value of neutrophil-to-lymphocyte ratio for atrial fibrillation and stroke in type 2 diabetes mellitus: a population-based cohort study

Introduction

Neutrophil-to-lymphocyte ratio (NLR) is a routinely available biomarker that reflects systemic inflammation. The study evaluated the predictive value of NLR for ischemic stroke and atrial fibrillation (AF) in patients with type 2 diabetes mellitus.

Methods

This was a population-based cohort study of patients with type 2 diabetes mellitus and complete blood count tests at baseline between January 1st, 2009 to December 31st, 2009 at government-funded hospitals/clinics in Hong Kong. Follow-up was until December 31st, 2019 or death.

Results

A total of 85351 patients (age=67.6±13.2 years old, male=48.8%, follow-up=3101±1441 days) were included. Univariable Cox regression found that increased NLR at quartiles 2, 3 and 4 was significantly associated with higher risks of new onset ischemic stroke (HR: 1.28 [1.20–1.37], P<0.001, HR: 1.41 [1.32–1.51], P<0.001 and HR: 1.38 [1.29–1.47], P<0.001) and AF (hazard ratio [HR]: 1.09 [1.02–1.17], P<0.015; HR: 1.28 [1.20–1.37], P<0.001; HR: 1.39 [1.31–1.49], P<0.001) compared to quartile 1. On multivariable analysis, NLR remained a significant predictor of ischemic stroke risk for quartiles 2 and 3 (quartile 2: HR: 1.14 [1.05, 1.22], p=0.001; quartile 3: HR: 1.14 [1.06, 1.23], p<0.001) but not quartile 4 (HR: 1.08 [0.994, 1.17], p=0.070). By contrast, NLR was not predictive of AF after adjusting for confounders (quartile 2: HR: 0.966 [0.874, 1.07], p=0.499; quartile 3: HR: 0.978 [0.884, 1.08], p=0.661; quartile 4: HR: 1.05 [0.935, 1.16], p=0.462).

Conclusion

NLR is a significant predictor of new onset ischaemic stroke but not AF after adjusting for significant confounders.

Funding Acknowledgement

Type of funding sources: None.

Cost-effectiveness of statin therapy in categories of patients in the UK

Background

Cardiovascular disease (CVD) mortality has declined steadily over the last few decades across Europe and North America.

Purpose

To provide contemporary estimates of long-term effectiveness and cost-effectiveness of statin therapy in different categories of patients in UK.

Methods

The CTT-UKB micro-simulation model, developed using the Cholesterol Treatment Trialists' Collaboration data (CTT: 118,000 participants; 5 years follow-up), and calibrated in the UK Biobank cohort (UKB: 502,000 participants; 9 years follow-up). The model integrates parametric risk equations for incident myocardial infarction, stroke, coronary revascularization, diabetes, cancer and vascular and nonvascular death, and projects annually these endpoints and survival using patient characteristics at entry. UKB data and linked primary and hospital care data informed healthcare costs in the model (2020 UK£); 2021 UK NHS Drug Tariff informed statin costs (atorvastatin 40mg at £1.22 and 80mg at £1.68 per 28 tablets); and Health Survey for England data informed health-related quality of life in the model. Previous CTT meta-analysis, atorvastatin dose-response randomized trials, and further meta-analyses of statin trials and cohort studies informed effects of 40mg/80mg atorvastatin therapy daily on rates of incident myocardial infarction, stroke, coronary revascularization, vascular death, diabetes, myopathy and rhabdomyolysis.

The model was used to project gains in quality-adjusted life years (QALYs) and additional cost per QALY with lifetime use of atorvastatin 40mg or 80mg daily in categories of UKB participants by sex, age at statin initiation (40–49; 50–59 and 60–70 years), and 10-year CVD risk (QRISK3 risk (%): <5; 5–10, 10–15, 15–20, ≥20). Further scenarios explored effects of 5-year delay of statin initiation in people under 45 years of age or stopping statin therapy at 80 years of age.

Results

Across men and women in categories by age and CVD risk, lifetime use of atorvastatin 40mg daily was associated with increases in survival by 0.44–1.69 years (0.28–1.02 QALYs), and atorvastatin 80mg daily with increases in survival of 0.45–1.87 years (0.32–1.13 QALYs; Figure 1) with gains larger among participants at higher CVD risk. Both atorvastatin 40mg and 80mg doses were in the range of cost-effective treatments with incremental cost per QALY gained with atorvastatin 40mg daily versus no statin therapy below £7200/QALY and with atorvastatin 80mg vs 40mg daily below £16000/QALY (Figure 2) across all patient categories studied. Compared to lifetime statin therapy, stopping therapy at 80 years of age substantially reduced benefits and was not cost-effective in any patient category studied. Similarly, compared to immediate initiation, 5-year delay of statin therapy in 40–45 years old patients was not a cost-effective.

Conclusions

In the UK, statin therapy remains highly cost-effective across men and women 40–70 years old, including those at 10-year CVD risk <5%.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme, UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme, UK Medical Research Council (MRC), British Heart Foundation

Benefit accrual with cardiovascular disease prevention and effects of discontinuation: a modelling study

Background

Statin therapy reduces rates of heart attacks and strokes and improves survival in people at increased cardiovascular disease (CVD) risk. However, there is some uncertainty when to start and how long to persist with statin therapy so as to optimise benefits.

Purpose

To project the accrual of benefit with statin therapy in population groups by age at therapy initiation using a newly developed micro-simulation model.

Methods

Participants without previous CVD (N=44,412) and with previous CVD (N=13,061) at entry were randomly selected from the UK Biobank cohort, ensuring sufficient representation in respective categories by age, LDL cholesterol, diabetes and 10-year CVD risk categories (QRISK3 score, for those without previous CVD only). The CTT-UKB model, a CVD micro-simulation model [1], was used to predict subsequent survival and quality-adjusted life years (QALYs) of the participants using their characteristics at entry. Treatment with atorvastatin 40mg daily was used as an example to illustrate the effect of the therapy compared to no such therapy. Scenarios include: (1) lifelong preventive therapy, (2) preventive therapy stopped at 80 years of age, and (3) delayed initiation of preventive therapy by 5 years in participants under 45 years of age.

Results

Statin treatment benefits, measured in QALYs gained, accrue over lifetime. The majority of benefits accrue later in life. Men accumulate larger benefits and earlier than women (Figure 1A). The pattern of benefits accrual is similar for participants with and without previous CVD (data not shown). The higher the participants' CVD risk, the larger and earlier the benefits, with younger participants accruing larger benefits (Figure 1B). Compared with lifelong prevention, stopping treatment at 80 years of age leads to large reductions in overall benefits, especially in women and those at lower CVD risk. For example, compared to lifelong therapy, people without previous CVD who initiate therapy in their 50s, would lose 47% of QALYs benefit (if men), 66% (if women), 73% (if with CVD risk <5%), and 35% (if with CVD risk ≥20%), respectively, if they stop treatment when they reach 80 years of age. Five-year delay of statin therapy initiation in people under 45 years of age reduces their benefits by about 4% on average, though the loss is somewhat larger in people at higher CVD risk (Figure 2).

Conclusion

Benefits from lifelong cardiovascular prevention accrue over peoples' lifespan with large share of benefits accruing at older age. Stopping treatment earlier substantially reduces benefits.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): UK NationalInstitute for Health Research (NIHR) Health Technology Assessment (HTA) Programme, UK Medical Research Council (MRC), and British Heart Foundation

Arbuscular mycorrhizal fungi: Effects on secondary metabolite accumulation of traditional Chinese medicines

Traditional Chinese medicine (TCM) has played a pivotal role in maintaining the health of people, and the intrinsic quality of TCM is directly related to the clinical efficacy. The medicinal ingredients of TCM are derived from the secondary metabolites of plant metabolism and are also the result of the coordination of various physiological activities in plants. Arbuscular mycorrhizal fungi (AMF) are among the most ubiquitous plant mutualists that enhance the growth and yield of plants by facilitating the uptake of nutrients and water. Symbiosis of AMF with higher plants promotes growth and helps in the accumulation of secondary metabolites. However, there is still no systematic analysis and summation of their roles in the application of TCM, biosynthesis and accumulation of active substances of herbs, as well as the mechanisms. AMF directly or indirectly affect the accumulation of secondary metabolites of TCM, which is the focus of this review. First, in this review, the effects of AMF symbiosis on the content of different secondary metabolites in TCM, such as phenolic acids, flavonoids, alkaloids and terpenoids, are summarized. Moreover, the mechanism of AMF regulating the synthesis of secondary metabolites was also considered, in combination with the establishment of mycorrhizal symbionts, response mechanisms of plant hormones, nutritional elements and expression of key enzyme their activities. Finally, combined with the current application prospects for AMF in TCM, future in-depth research is planned, thus providing a reference for improving the quality of TCM. In this manuscript, we review the research status of AMF in promoting the accumulation of secondary metabolites in TCM to provide new ideas and methods for improving the quality of TCM.

Association between maternal oxygenation and brain growth in fetuses with left-sided cardiac obstructive lesions

OBJECTIVE

Impaired brain growth has been observed in fetuses with left-sided obstructive lesions (LSOL). Maternal oxygenation (MO) can alter fetal cerebral oxygenation and vascular reactivity. Our aim was to observe whether brain growth improves during MO in fetuses with LSOL.

METHODS

Forty-six fetuses with LSOL and 23 control fetuses were enrolled in this prospective longitudinal study. Fetuses with LSOL were subgrouped into those with MO (LSOL-MO, n = 23) and those without MO (LSOL-nMO, n = 23). Fetal head circumference (HC) and total intracranial volume (TIV) were evaluated serially at 4-week intervals. Brain biometry and growth were analyzed using linear mixed models adjusted for gestational age and sex. Spearman's correlation coefficients were calculated to identify baseline characteristics predictive of brain growth in the LSOL-MO group.

RESULTS

Duration of MO therapy had significant interaction effects on cerebral biometry in fetuses with LSOL. TIV increased more rapidly after 8 weeks of oxygen exposure and HC was larger after 16 weeks of oxygen exposure in the LSOL-MO group compared with the LSOL-nMO group (P < 0.001). The change in TIV at the final time- point relative to the initial timepoint in the LSOL-MO group correlated negatively with the baseline pulsatility index of the middle cerebral artery (r = -0.58, P = 0.003) and baseline myocardial performance index of the left ventricle (r = -0.68, P < 0.001).

CONCLUSIONS

TIV and HC increased faster in fetuses with LSOL which had MO compared with those that did not. Lower cerebral vascular resistance and preserved left heart function at baseline may predict greater cerebral biometric growth during MO. Additional research, including larger serial studies, is needed to confirm these preliminary findings and evaluate the clinical application of MO in this population. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Clinicopathologic and prognostic significance of long non-coding RNA myocardial infarction-associated transcript in multiple cancers

OBJECTIVE

The aim of the meta-analysis was to explore the clinicopathological and prognostic significance of long non-coding RNA (lncRNA) myocardial infarction-associated transcript (MIAT) in various cancers.

MATERIALS AND METHODS

We searched multiple databases, including PubMed, China National Knowledge 53 Infrastructure (CNKI), Springer, Web of Science, and Cochrane, for articles on the prognostic value of lncRNA MIAT in various cancers before 25 March 2021. The odds ratio (OR) and 95% confidence interval (CI) were adopted to evaluate the clinicopathological features and outcomes of cancers. The Cancer Genome Atlas dataset was used to identify the differential expression and prognostic significance of lncRNA MIAT.

RESULTS

We enrolled 14 publications, including 1,573 cancer patients. Higher lncRNA MIAT expression was significantly related to worse overall survival (OR=3.13, 95% CI: 2.47-3.96, p<0.05), regardless of cancer types, sample size, and follow-up time of the included studies. Additionally, higher lncRNA MIAT expression was associated with larger tumour sizes (OR=1.67, 95% CI: 1.24-2.26, p<0.05), advanced clinical stage (OR=4.79, 95% CI: 3.38-6.79, p<0.05), lymph nodes metastasis (OR=7.33, 95% CI: 4.61-11.67, p<0.05), and distant metastasis (OR=2.62, 95% CI: 1.88-3.66, p<0.05), but not associated with age and gender. We found no publication bias, and sensitivity analysis indicated that the results were reliable.

CONCLUSIONS

Higher lncRNA MIAT expression may predict larger tumour sizes, advanced clinical stage, metastasis of cancers, and lower overall survival rate. LncRNA MIAT may serve as a useful clinicopathological and prognostic biomarker for cancers.