Effect of total cholesterol level variabilities on cerebrovascular disease

OBJECTIVE

Hyperlipidemia is a risk factor of cerebrovascular disease (CVD). However, the relationship between CVD and cholesterol variability is less clear. This study assesses the relationship between cholesterol change and CVD risk.

PATIENTS AND METHODS

We reviewed 480,830 people from 20 to 99 years with 2 health check-ups from 2002 to 2015 from the Korean National Health Insurance (KNHI) database. People's baseline and follow-up cholesterol levels were classified into low (<180 mg/dL), moderate (≥180 mg/dL and <240 mg/dL), and high (≥240 mg/dL). Participants were divided into 9 groups (low-to-low, low-to-moderate, low-to-high, moderate-to-low, moderate-to-moderate, moderate-to-high, high-to-low, high-to-moderate, high-to-high).

RESULTS

Low to high cholesterol level is associated with hemorrhagic stroke (aHR1 = 1.59; 95% CI 1.12-2.28 and aHR2 = 1.56; 95% CI 1.07-2.25). Low to moderate/high cholesterol level is associated with ischemic stroke and occlusion/stenosis (for low to moderate, aHR1 = 1.11; 95% CI 1.04-1.17 and aHR2 = 1.14; 95% CI 1.07-1.21 for ischemic stroke and aHR1 = 1.18; 95% CI 1.07-1.29 and aHR2 = 1.20; 95% CI 1.08-1.32 for occlusion/stenosis, for low to high, aHR1 = 1.42; 95% CI 1.20-1.67 and aHR2 = 1.28; 95% CI 1.08-1.52 for ischemic stroke and aHR1 = 1.86; 95% CI 1.46-2.36 and aHR2= 1.74; 95% CI 1.36-2.23 for occlusion/stenosis). Moderate to high cholesterol level is associated with ischemic stroke and occlusion/stenosis (for ischemic stroke, aHR1 = 1.12; 95% CI 1.05-1.20 and aHR2 = 1.10; 95% CI 1.03-1.17, for occlusion/stenosis, aHR1 = 1.21; 95% CI 1.10-1.33 and aHR2 = 1.19; 95% CI 1.08-1.32). Moderate to low cholesterol level is associated with ischemic and hemorrhagic stroke and occlusion/stenosis (for ischemic, aHR1 = 1.15; 95% CI 1.09-1.21, for hemorrhagic, aHR1 = 1.14; 95% CI 1.01-1.28, for occlusion/stenosis, aHR1 = 1.14; 95% CI 1.05-1.23). High to low cholesterol level is associated with ischemic stroke and occlusion/stenosis (for ischemic stroke, aHR1 = 1.51; 95% CI 1.33-1.71 and aHR2 = 1.20; 95% CI 1.05-1.36, for occlusion/stenosis, aHR1 = 1.50; 95% CI 1.24-1.81).

CONCLUSIONS

Our study shows that cholesterol changes, especially larger changes, lead to an increase in CVD, which demonstrates that cholesterol variability may increase CVD.

Bifidobacterium longum DS0956 and Lactobacillus rhamnosus DS0508 culture-supernatant ameliorate obesity by inducing thermogenesis in obese-mice

Excessive body fat and the related dysmetabolic diseases affect both developed and developing countries. The aim of this study was to investigate the beneficial role of a bacterial culture supernatant (hereafter: BS) of Lactobacillus and Bifidobacterium and their potential mechanisms of action on white-fat browning and lipolysis. For selection of four candidates among 55 Lactic acid producing bacteria (LAB) from human infant faeces, we evaluated by Oil Red O staining and Ucp1 mRNA quantitation in 3T3-L1 preadipocytes. The expression of browning and lipolysis markers was examined along with in vitro assays. The possible mechanism was revealed by molecular and biological experiments including inhibitor and small interfering RNA (siRNA) assays. In a mouse model, physiological, histological, and biochemical parameters and expression of some thermogenesis-related genes were compared among six experimental groups fed a high-fat diet and one normal-diet control group. The results allow us to speculate that BS treatment promotes browning and lipolysis both in vitro and in vivo. Moreover, the BS may activate thermogenic programs via a mechanism involving PKA-CREB signaling in 3T3-L1 cells. According to our data, we can propose that two LAB strains, Bifidobacterium longum DS0956 and Lactobacillus rhamnosus DS0508, may be good candidates for a dietary supplement against obesity and metabolic diseases; however, further research is required for the development as dietary supplements or drugs.

Development of Noonan syndrome by deregulation of allosteric SOS autoactivation

Ras family proteins play an essential role in several cellular functions, including growth, differentiation, and survival. The mechanism of action of Ras mutants in Costello syndrome and cancers has been identified, but the contribution of Ras mutants to Noonan syndrome, a genetic disorder that prevents normal development in various parts of the body, is unknown. Son of Sevenless (SOS) is a Ras guanine nucleotide exchange factor. In response to Ras-activating cell signaling, SOS autoinhibition is released and is followed by accelerative allosteric feedback autoactivation. Here, using mutagenesis-based kinetic and pulldown analyses, we show that Noonan syndrome Ras mutants I24N, T50I, V152G, and D153V deregulate the autoactivation of SOS to populate their active form. This previously unknown process has been linked so far only to the development of Noonan syndrome. In contrast, other Noonan syndrome Ras mutants-V14I, T58I, and G60E-populate their active form by deregulation of the previously documented Ras GTPase activities. We propose a novel mechanism responsible for the deregulation of SOS autoactivation, where I24N, T50I, V152G, and D153V Ras mutants evade SOS autoinhibition. Consequently, they are capable of forming a complex with the SOS allosteric site, thus aberrantly promoting SOS autoactivation, resulting in the population of active Ras mutants in cells. The results of this study elucidate the molecular mechanism of the Ras mutant-mediated development of Noonan syndrome.

How Do Caregivers of Children with Congenital Heart Disease Navigate the Health Care System in Ethiopia?

Research Objective

Global surgery is becoming an increasingly important global health agenda. Cardiovascular disease is the major cause of mortality around the world, and congenital heart disease is the leading cause of morbidity in children. This study aimed to investigate and illustrate the caregivers’ experiences of accessing the health care system and undergoing pediatric cardiac surgery for children with congenital heart disease (CHD).

Study Design

A qualitative study was conducted. Interviews were conducted in December 2019 in Amharic, then translated into English using trained local interpreters. Data were transcribed verbatim and analyzed according to the principles of interpretive thematic analysis, informed by the candidacy framework, using NVivo. The candidacy framework explores the access to health care utilization by seven elements: candidacy, navigation, the permeability of services, appearances at health services, adjudications, offers and resistance, and operating conditions and the local production of candidacy.

Population Studied

Interviews were conducted with 13 caregivers of 10 patients with congenital heart disease that received cardiac surgery during the week of the interview.

Principal Findings

The following three themes emerged from the interviews: (a) Recognition of CHD mostly took place at birth, but for those born at home, they found out much later (max 14 years); (b) CHD was misdiagnosed multiple times prior to seeking care at a large hospital; and (c) patients were waiting for the surgery for more than a year, (d) being scheduled for surgery induced both anxiety and hopefulness. In the discussion, caregivers had financial difficulties and struggled in a fragmented delivery system and experienced poor service quality such as the inaccuracy of diagnosis while navigating the Ethiopian health care system.

Conclusions

Major care‐seeking delays were related to the inefficient and complex health care system, largely due to lack of early CHD recognition and financial hardships. Financial protection is low despite the availability of fee waivers for medications. Low education attainment and distance to hospitals are contributing to this challenge.

Implications for Policy or Practice

Overall, Ethiopia needs to prioritize policies that protect the financial status of low‐income households that need health care services. Along with increasing health care workforce capacity for pediatric cardiac surgeries in Ethiopia, there is a need to strengthen the district‐level screening capacity to facilitate earlier diagnosis at easily accessible health care settings.

Primary Funding Source

Search Results Web results Korea International Cooperation Agency.

Synthesis and characterization of iodovanadinite using PdI2, an iodine source for the immobilisation of radioiodine

The synthesis of a palladium-containing iodovanadinite derivative, hypothetically “PdPb₉(VO₄)₆I₂”, was attempted using PdI₂ as a source of iodine in searching for a novel waste form for radioiodine. Stoichiometric amounts of Pb₃(VO₄)₂ and PdI₂ were batched and reacted at elevated temperatures in sealed vessels. Batched material was also subjected to high-energy ball-milling (HEBM) in order to reduce reaction time and the potential for iodine volatilization during subsequent reaction at 200–500 °C. The resulting products were characterized using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, IR spectroscopy, thermal analysis and Pd K XANES. Results showed that PdI₂ can function as a sacrificial iodine source for the formation of iodovanadinite, prototypically Pb₁₀(VO₄)₆I₂, however, the incorporation of Pd into this phase was not definitively observed. The sacrificial reaction mechanism involved the decomposition of PdI₂ to Pd metal and nascent I₂, with the latter incorporated into the iodovanadinite Pb₁₀(VO₄)₆I₂ phase. In comparison to processing using standard solid state reaction techniques, the use of HEBM prior to high temperature reaction generates a more homogeneous end-product with better iodine retention for this system. Overall, the key novelty and importance of this work is in demonstrating a method for direct immobilisation of undissolved PdI₂ from nuclear fuel reprocessing, in a composite wasteform in which I-129 is immobilised within a durable iodovandinite ceramic, encapsulating Pd metal.

The synthesis and characterisation of a composite wasteform, comprising iodovanadinite Pb₁₀(VO₄)₆I₂ and Pd metal, is reported, for immobilisation of radioiodine PdI₂; the formation of Pd incorporated iodovanadinite “PdPb₉(VO₄)₆I₂” was not observed.

Vaccinia-based oncolytic immunotherapy Pexastimogene Devacirepvec in patients with advanced hepatocellular carcinoma after sorafenib failure: a randomized multicenter Phase IIb trial (TRAVERSE)

Pexastimogene devacirepvec (Pexa-Vec) is a vaccinia virus-based oncolytic immunotherapy designed to preferentially replicate in and destroy tumor cells while stimulating anti-tumor immunity by expressing GM-CSF. An earlier randomized Phase IIa trial in predominantly sorafenib-naïve hepatocellular carcinoma (HCC) demonstrated an overall survival (OS) benefit. This randomized, open-label Phase IIb trial investigated whether Pexa-Vec plus Best Supportive Care (BSC) improved OS over BSC alone in HCC patients who failed sorafenib therapy (TRAVERSE).

129 patients were randomly assigned 2:1 to Pexa-Vec plus BSC vs. BSC alone. Pexa-Vec was given as a single intravenous (IV) infusion followed by up to 5 IT injections. The primary endpoint was OS. Secondary endpoints included overall response rate (RR), time to progression (TTP) and safety.

A high drop-out rate in the control arm (63%) confounded assessment of response-based endpoints. Median OS (ITT) for Pexa-Vec plus BSC vs. BSC alone was 4.2 and 4.4 months, respectively (HR, 1.19, 95% CI: 0.78–1.80; p = .428). There was no difference between the two treatment arms in RR or TTP. Pexa-Vec was generally well-tolerated. The most frequent Grade 3 included pyrexia (8%) and hypotension (8%). Induction of immune responses to vaccinia antigens and HCC associated antigens were observed.

Despite a tolerable safety profile and induction of T cell responses, Pexa-Vec did not improve OS as second-line therapy after sorafenib failure. The true potential of oncolytic viruses may lie in the treatment of patients with earlier disease stages which should be addressed in future studies.

ClinicalTrials.gov: NCT01387555

Concurrent hyperthermia and re-irradiation for recurrent high-grade gliomas

Salvage therapy for recurrent high grade gliomas (HGG) includes surgery, radiotherapy and chemotherapy, however, standard treatment does not exist. We evaluated the tolerability and efficacy of re-irradiation (re-RT) with hyperthermia (HT) for patients with recurrent HGG. From September 2010 to July 2015, 20 patients with recurrent HGG were treated with re-RT and HT. The radiotherapy dose of 30 Gray (Gy) was delivered with 2 Gy per fraction daily, and HT was performed twice weekly. Primary endpoints were treatment compliance and toxicity. Second endpoints were overall survival (OS) and progression free survival (PFS). The median interval between initial RT and re-RT was 11 months. During re-RT with HT, there were no significant acute morbidities over grade 3. Median overall survival (OS) from re-irradiation was 8.4 months and the 6 and 12 months survival rate were 67% and 30%, respectively. The median progression free survival (PFS) from re-irradiation was 4.1 month. Our findings suggested that concurrent re-RT with HT was a safe and well-tolerated. In addition, the combination re-RT and HT could be a valuable salvage treatment option for selected recurrent HGG patients with poor performance status.

Allosteric autoactivation of SOS and its kinetic mechanism

Son of Sevenless (SOS), one of guanine nucleotide exchange factors (GEFs), activates Ras. We discovered that the allosteric domain of SOS yields SOS to proceed a previously unrecognized autoactivation kinetics. Its essential feature is a time-dependent acceleration of SOS feedback activation with a reaction initiator or with the priming of active Ras. Thus, this mechanistic autoactivation feature explains the notion, previously only conjectured, of accelerative SOS activation followed by the priming of active Ras, an action produced by another GEF Ras guanyl nucleotide-releasing protein (RasGRP). Intriguingly, the kinetic transition from gradual RasGRP activation to accelerative SOS activation has been interpreted as an analog to digital conversion; however, from the perspective of autoactivation kinetics, it is a process of straightforward RasGRP-mediated SOS autoactivation. From the viewpoint of allosteric protein cooperativity, SOS autoactivation is a unique time-dependent cooperative SOS activation because it enables an active SOS to accelerate activation of other SOS as a function of time. This time-dependent SOS cooperativity does not belong to the classic steady-state protein cooperativity, which depends on ligand concentration. Although its hysteretic or sigmoid-like saturation curvature is a classic hallmark of steady-state protein cooperativity, its hyperbolic saturation figure typically represents protein noncooperativity. We also discovered that SOS autoactivation perturbs the previously predicted hysteresis of SOS activation in a steady state to produce a hyperbolic saturation curve. We interpret this as showing that SOS allostery elicits, through SOS autoactivation, cooperativity uniquely time-dependent but not ligand concentration dependent.