Prevalence and impact of depression and anxiety among older myocardial infarction survivors: A nationwide cohort study

BACKGROUND

Depression and anxiety may be significant prognostic factors after myocardial infarction (MI). Thus, we investigated depression and anxiety prevalence among older MI survivors and their impact on mortality, stroke, and recurrent MI.

METHODS

This population-based cohort study used the Korean National Health Insurance Service database for data concerning individuals aged 66 years who participated in the National Screening Program from 2009 to 2016. Overall, 11,721 individuals with MI history and 58,605 age- and sex-matched controls were included and followed up until 2019. The presence of depression and anxiety was assessed 2 years before and after participation in the program. Mortality and major adverse outcomes, defined as a composite outcome comprising mortality, stroke, and recurrent MI, were analyzed.

RESULTS

Depression and anxiety prevalence among MI survivors was 20.4 % and 30.3 %, respectively. Crude odds ratios for depression and anxiety, compared with the control group, were 1.207 (1.148-1.269) and 1.078 (1.032-1.126), respectively. During the follow-up, individuals with depression, anxiety, or both showed increased hazard ratios (HRs) for mortality and major adverse outcomes; after adjustments, their HRs were 1.442 (1.182-1.759), 1.129 (0.960-1.328), and 1.498 (1.263-1.776), respectively, for mortality and 1.505 (1.289-1.758), 1.158 (1.021-1.314), and 1.530 (1.337-1.751), respectively, for major adverse outcomes.

LIMITATIONS

Although this was a nationwide cohort study, the MI, depression, and anxiety diagnoses were based on diagnostic codes.

CONCLUSIONS

Higher depression and anxiety prevalence was observed among older MI survivors. Depression and anxiety occurrence correlated with increased adverse clinical outcomes after adjustments.

Efficient production of (S)-limonene and geraniol in Saccharomyces cerevisiae through the utilization of an Erg20 mutant with enhanced GPP accumulation capability

Monoterpenes and monoterpenoids such as (S)-limonene and geraniol are valuable chemicals with a wide range of applications, including cosmetics, pharmaceuticals, and biofuels. Saccharomyces cerevisiae has proven to be an effective host to produce various terpenes and terpenoids. (S)-limonene and geraniol are produced from geranyl pyrophosphate (GPP) through the enzymatic actions of limonene synthase (LS) and geraniol synthase (GES), respectively. However, a major hurdle in their production arises from the dual functionality of the Erg20, a farnesyl pyrophosphate (FPP) synthase, responsible for generating GPP. Erg20 not only synthesizes GPP by condensing isopentenyl pyrophosphate (IPP) with dimethylallyl pyrophosphate but also catalyzes further condensation of IPP with GPP to produce FPP. In this study, we have tackled this issue by harnessing previously developed Erg20 mutants, Erg20K197G (Erg20G) and Erg20F96W, N127W (Erg20WW), which enhance GPP accumulation. Through a combination of these mutants, we generated a novel Erg20WWG mutant with over four times higher GPP accumulating capability than Erg20WW, as observed through geraniol production levels. The Erg20WWG mutant was fused to the LS from Mentha spicata or the GES from Catharanthus roseus for efficient conversion of GPP to (S)-limonene and geraniol, respectively. Further improvements were achieved by localizing the entire mevalonate pathway and the Erg20WWG-fused enzymes in peroxisomes, while simultaneously downregulating the essential ERG20 gene using the glucose-sensing HXT1 promoter. In the case of (S)-limonene production, additional Erg20WWG-LS was expressed in the cytosol. As a result, the final strains produced 1063 mg/L of (S)-limonene and 1234 mg/L of geraniol by fed-batch biphasic fermentations with ethanol feeding. The newly identified Erg20WWG mutant opens doors for the efficient production of various other GPP-derived chemicals including monoterpene derivatives and cannabinoids.

Attitude Toward Virtual Rehabilitation and Active Video Games Among Therapists in Korea: A Nationwide Survey

In this study, we conducted a survey targeting 191 physical therapists (PTs) and 159 occupational therapists (OTs) in South Korea to explore attitudes toward virtual rehabilitation. Utilizing the Korean version of the ADOPT VR by Glegg et al., OT exhibited significantly more experience with virtual reality (VR) and active video games (AVG) than PT. Therapists with VR/AVG experience scored significantly higher in most categories, and the scores in each category were significantly correlated with the Behavioral Intention category, reflecting the willingness to use VR/AVG. The biggest barriers identified were insufficient funds and setup assistance for the equipment. Differences in responses between the groups with and without VR/AVG experience were most prominent in terms of lack of interest and funding. Therapists' attitudes, perceptions, and intentions toward VR/AVG are crucial factors in the establishment and implementation of VR/AVG; thus, the results of this study provide valuable evidence for future policies related to VR/AVG in rehabilitation medicine.

An analysis of contributing factors of head and neck space infections of odontogenic origin: A long-term retrospective clinical study (including COVID-19 pandemic period)

BACKGROUND

The purpose of this study is to investigate predisposing factors for the head and neck infections (HNIs), regarding to the demographic data, anatomical spaces, microbiology and antibiotic sensitivity for affected patients.

MATERIAL AND METHODS

A 13-year of retrospective study evaluating 470 patients with HNIs, treated as inpatient management in the Department of Oral and Maxillofacial Surgery of KyungHee University school of Dentistry, Seoul, Korea, from January 2009 to February 2022. Statistical analysis of demographic, time-related, anatomic, microbiologic, and treatment variables were investigated for each patient.

RESULTS

The frequency of HNIs was significantly higher in 50's in males, followed by 70's in females. High Severity score (SS) were significantly associated with increased LOH (Length of hospital stay) and LOM (Length of medication), while LOH showed more intensive relationship compared with LOM. The most frequently involved space in abscess was submandibular space, though incidence and severity of HNIs shows declining tendency throughout 13-year research. Streptococcus viridans was the most predominant species isolated from pus culture growth, and a combination of ampicillin and sulbactam was the 1st choice of antibiotics intravenously. According to the comparison analysis between recommended antibiotics from resistance testing result and clinically administered antibiotics, final coincidence rate was estimated about 55%.

CONCLUSIONS

Due to HNIs being multifactorial, predicting progression and management of HNIs is still a challenge for oral and maxillofacial surgeons. The present study showed several predisposing factors of SHNIs and their correlations, which could contribute to earlier diagnosis and more effective treatment planning for clinicians, thereby leading to the improvement of prognosis for patients, ultimately.

Women's Cardiac Rehabilitation Barriers: Results of the International Council of Cardiovascular Prevention and Rehabilitation's First Global Assessment

BACKGROUND

Cardiac rehabilitation (CR) programs are underutilized globally, especially by women. In this study we investigated sex differences in CR barriers across all world regions, to our knowledge for the first time, the characteristics associated with greater barriers in women, and women's greatest barriers according to enrollment status.

METHODS

In this cross-sectional study, the English, Simplified Chinese, Arabic, Portuguese, or Korean versions of the Cardiac Rehabilitation Barriers Scale was administered to CR-indicated patients globally via Qualtrics from October 2021 to March 2023. Members of the International Council of Cardiovascular Prevention and Rehabilitation community facilitated participant recruitment. Mitigation strategies were provided and rated.

RESULTS

Participants were 2163 patients from 16 countries across all 6 World Health Organization regions; 916 (42.3%) were women. Women did not report significantly greater total barriers overall, but did in 2 regions (Americas, Western Pacific) and men in 1 (Eastern Mediterranean; all P < 0.001). Women's barriers were greatest in the Western Pacific (2.6 ± 0.4/5) and South East Asian (2.5 ± 0.9) regions (P < 0.001), with lack of CR awareness as the greatest barrier in both. Women who were unemployed reported significantly greater barriers than those not (P < 0.001). Among nonenrolled referred women, the greatest barriers were not knowing about CR, not being contacted by the program, cost, and finding exercise tiring or painful. Among enrolled women, the greatest barriers to session adherence were distance, transportation, and family responsibilities. Mitigation strategies were rated as very helpful (4.2 ± 0.7/5).

CONCLUSIONS

CR barriers-men's and women's-vary significantly according to region, necessitating tailored approaches to mitigation. Efforts should be made to mitigate unemployed women's barriers in particular.

Translation, Cultural Adaptation, and Validation of a Korean Version of the Information Needs in Cardiac Rehabilitation Scale

OBJECTIVE

: To translate and culturally adapt the Information Needs in Cardiac Rehabilitation (INCR) questionnaire into Korean and perform psychometric validation.

METHODS

: The original English version of the INCR, in which patients are asked to rate the importance of 55 topics, was translated into Korean (INCR-K) and culturally adapted. The INCR-K was tested on 101 cardiac rehabilitation (CR) participants at Kangwon National University Hospital and Seoul National University Bundang Hospital in Korea. Structural validity was assessed using principal component analysis, and Cronbach's alpha of the areas was computed. Criterion validity was assessed by comparing information needs according to CR duration and knowledge sufficiency according to receipt of education. Half of the participants were randomly selected for 1 month of re-testing to assess their responsiveness.

RESULTS

: Following cognitive debriefing, the number of items was reduced to 41 and ratings were added to assess participants' sufficient knowledge of each item. The INCR-K structure comprised eight areas, each with sufficient internal consistency (Cronbach's alpha>0.7). Criterion validity was supported by significant differences in mean INCR-K scores based on CR duration and knowledge sufficiency ratings according to receipt of education (p<0.05). Information needs and knowledge sufficiency ratings increased after 1 month of CR, thus supporting responsiveness (p<0.05).

CONCLUSION

: The INCR-K demonstrated adequate face, content, cross-cultural, structural, and criterion validities, internal consistency, and responsiveness. Information needs changed with CR, such that multiple assessments of information needs may be warranted as rehabilitation progresses to facilitate patient-centered education.

Investigation of the efficacy of low-frequency repetitive transcranial magnetic stimulation on upper-limb motor recovery in subacute ischemic stroke without cortical involvement: a protocol paper for a multi-center, double-blind randomized controlled trial

Introduction

The incidence of stroke is increasing steadily due to factors such as population aging. Approximately 80% of stroke survivors have motor disorders affecting their daily lives. Repetitive transcranial magnetic stimulation (rTMS) has been reported to maximize functional recovery after stroke along with exercise intervention in upper limb rehabilitation treatment. However, whether rTMS affects the recovery of upper limb function in patients with stroke remains unclear. Therefore, in this trial, we will investigate the efficacy of low-frequency rTMS in patients with subcortical and brainstem ischemic stroke.

Methods

This study has been designed as a multi-center, double-blind, randomized controlled trial to compare the efficacy of low-frequency rTMS over the contralesional M1 with sham stimulation. Overall, 88 participants will be allocated to the intervention or control group in a 1:1 ratio, with stratification according to their initial upper extremity Fugl-Meyer assessment (UE-FMA) score. The participants will receive either 30 min of real rTMS (intervention group) or sham rTMS (control group), followed by 30 min of occupational therapy for 10 consecutive workdays. All the participants will receive the same amount of rehabilitation therapy throughout the intervention period. Evaluations will be performed at baseline (T0), at the end of treatment (T1), and 4 weeks after the end of treatment (T2), including the box and block test (BBT), UE-FMA, Korean version of the Modified Barthel Index, and NIH Stroke Scale scores, Finger tapping test, Brunnstrom stage, modified Ashworth scale, and grip strength. The primary outcome will be the change in the BBT score between T0 and T2.

Conclusion

This study will provide evidence on the efficacy of low-frequency rTMS in motor function recovery of the upper limb in patients with subacute, subcortical, and brainstem ischemic stroke.

Clinical trial registration

ClinicalTrials.gov, identifier [NCT05535504].

Regulation of acetate tolerance by small ORF-encoded polypeptides modulating efflux pump specificity in Methylomonas sp. DH-1

BACKGROUND

Methanotrophs have emerged as promising hosts for the biological conversion of methane into value-added chemicals, including various organic acids. Understanding the mechanisms of acid tolerance is essential for improving organic acid production. WatR, a LysR-type transcriptional regulator, was initially identified as involved in lactate tolerance in a methanotrophic bacterium Methylomonas sp. DH-1. In this study, we investigated the role of WatR as a regulator of cellular defense against weak organic acids and identified novel target genes of WatR.

RESULTS

By conducting an investigation into the genome-wide binding targets of WatR and its role in transcriptional regulation, we identified genes encoding an RND-type efflux pump (WatABO pump) and previously unannotated small open reading frames (smORFs), watS1 to watS5, as WatR target genes activated in response to acetate. The watS1 to watS5 genes encode polypeptides of approximately 50 amino acids, and WatS1 to WatS4 are highly homologous with one predicted transmembrane domain. Deletion of the WatABO pump genes resulted in decreased tolerance against formate, acetate, lactate, and propionate, suggesting its role as an efflux pump for a wide range of weak organic acids. WatR repressed the basal expression of watS genes but activated watS and WatABO pump genes in response to acetate stress. Overexpression of watS1 increased tolerance to acetate but not to other acids, only in the presence of the WatABO pump. Therefore, WatS1 may increase WatABO pump specificity toward acetate, switching the general weak acid efflux pump to an acetate-specific efflux pump for efficient cellular defense against acetate stress.

CONCLUSIONS

Our study has elucidated the role of WatR as a key transcription factor in the cellular defense against weak organic acids, particularly acetate, in Methylomonas sp. DH-1. We identified the genes encoding WatABO efflux pump and small polypeptides (WatS1 to WatS5), as the target genes regulated by WatR for this specific function. These findings offer valuable insights into the mechanisms underlying weak acid tolerance in methanotrophic bacteria, thereby contributing to the development of bioprocesses aimed at converting methane into value-added chemicals.

Trends in the incidence and prevalence of dysphagia requiring medical attention among adults in South Korea, 2006-2016: A nationwide population study

The prevalence of dysphagia is increasing, resulting in socioeconomic burden, but previous reports have only been based on a limited populations. Therefore, we aimed to investigate the nationwide incidence and prevalence of dysphagia requiring medical attention to provide adequate information for healthcare planning and resource allocation. In this nationwide retrospective cohort study, the data of adults aged ≥20 years recorded from 2006 to 2016 were sourced from the Korean National Health Insurance Service database. Medical claim codes based on ICD-10-CM were used to define dysphagia and possible causes. The annual incidence and prevalence of dysphagia were calculated. Cox regression was used to estimate dysphagia risk in people with possible dysphagia etiology. Survival analysis was performed to estimate the mortality and hazard ratio of dysphagia. The crude annual incidence of dysphagia increased continuously from 7.14 in 2006 to 15.64 in 2016. The crude annual prevalence of dysphagia in 2006 was 0.09% and increased annually to 0.25% in 2016. Stroke (odds ratio [OR]: 7.86, 95% confidence interval [CI]: 5.76-6.68), neurodegenerative disease (OR: 6.20, 95% CI: 5.76-6.68), cancer (OR: 5.59, 95% CI: 5.17-6.06), and chronic obstructive pulmonary disease (OR: 2.94, 95% CI: 2.71-3.18) were associated with a high risk of dysphagia. The mortality in the dysphagia group was 3.12 times higher than that in the non-dysphagia group (hazard ratio: 3.12, 95% CI: 3.03-3.23). The incidence and prevalence of dysphagia requiring medical attention are increasing annually. The increasing trend was conspicuous in the geriatric population. The presence of stroke, neurodegenerative disease, cancer, and chronic obstructive pulmonary disease is associated with a high risk of dysphagia. Therefore, adequate screening, diagnosis, and management of dysphagia in the older population must be emphasized in geriatric healthcare.

Critical roles of metal-ligand complexes in the controlled synthesis of various metal nanoclusters

Metal nanoclusters (NCs), an important class of nanoparticles (NPs), are extremely small in size and possess quasi-molecular properties. Due to accurate stoichiometry of constituent atoms and ligands, NCs have strong structure-property relationship. The synthesis of NCs is seemingly similar to that of NPs as both are formed by colloidal phase transitions. However, they are considerably different because of metal-ligand complexes in NC synthesis. Reactive ligands can convert metal salts to complexes, actual precursors to metal NCs. During the complex formation, various metal species occur, having different reactivity and fraction depending on synthetic conditions. It can alter their degree of participation in NC synthesis and the homogeneity of final products. Herein, we investigate the effects of complex formation on the entire NC synthesis. By controlling the fraction of various Au species showing different reactivity, we find that the extent of complex formation alters reduction kinetics and the uniformity of Au NCs. We demonstrate that this concept can be universally applied to synthesize Ag, Pt, Pd, and Rh NCs.

First Direct Measurement Constraining the ^{34}Ar(α,p)^{37}K Reaction Cross Section for Mixed Hydrogen and Helium Burning in Accreting Neutron Stars

The rate of the final step in the astrophysical αp process, the ^{34}Ar(α,p)^{37}K reaction, suffers from large uncertainties due to a lack of experimental data, despite having a considerable impact on the observable light curves of x-ray bursts and the composition of the ashes of hydrogen and helium burning on accreting neutron stars. We present the first direct measurement constraining the ^{34}Ar(α,p)^{37}K reaction cross section, using the Jet Experiments in Nuclear Structure and Astrophysics gas jet target. The combined cross section for the ^{34}Ar,Cl(α,p)^{37}K,Ar reaction is found to agree well with Hauser-Feshbach predictions. The ^{34}Ar(α,2p)^{36}Ar cross section, which can be exclusively attributed to the ^{34}Ar beam component, also agrees to within the typical uncertainties quoted for statistical models. This indicates the applicability of the statistical model for predicting astrophysical (α,p) reaction rates in this part of the αp process, in contrast to earlier findings from indirect reaction studies indicating orders-of-magnitude discrepancies. This removes a significant uncertainty in models of hydrogen and helium burning on accreting neutron stars.

Incidence of dysphagia requiring medical attention in various types of cancers: A nationwide population-based cohort study

PURPOSE

Most previous reports on dysphagia in cancer have focused on specific cancer types, particularly head and neck cancer. Therefore, we aimed to investigate the incidence of dysphagia in patients with various cancers using a nationwide database in South Korea.

METHODS

This was a retrospective cohort study using the National Health Insurance Service database. Claim codes were used for the selection criteria and operational definitions. The total population data from 2010 to 2015 were extracted. The crude incidence of dysphagia was calculated per 1,000 person-years. The multivariate adjusted Cox proportional hazards regression was used to determine the effects of different cancers on the incidence of dysphagia.

RESULTS

People with cancer had a lower income and suffered from a higher risk of comorbidities compared to people without cancer. The risk of dysphagia increased in all types of cancers, particularly in the oral cavity and pharynx (hazard ratio [HR]: 20.65, 95% confidence interval [CI]: 17.73-24.06), esophagus (HR: 18.25, 95% CI: 15.66-21.26), larynx (HR: 12.87, 95% CI: 10.33-16.02), and central nervous system (HR: 12.42, 95% CI: 10.33-14.94).

CONCLUSIONS

The risk of dysphagia was significantly higher in the cancer group than in the non-cancer group. As the survival of cancer patients is improving with the development of new treatments, more attention should be paid to dysphagia in the management of cancer. Prompt and appropriate multidisciplinary interventions for dysphagia are necessary to improve the recovery and quality of life in cancer patients.

Dysphagia Requiring Medical Attention in Parkinson's Disease: A Korean Population-Based Study

BACKGROUND

Patients with Parkinson's disease (PD) experience both motor and non-motor symptoms, including dysphagia. Although PD is closely associated with dysphagia, the prevalence or risk of dysphagia in PD is unclear, especially in Asian countries.

METHODS

The prevalence of PD and dysphagia with PD in the general population was analyzed using the Korean National Health Insurance Service (NHIS) database. The prevalence per 100,000 persons of PD and dysphagia with PD from 2006 to 2015 was analyzed in the general population aged ≥ 40 years. Patients newly diagnosed with PD between 2010 and 2015 were compared with those without PD.

RESULTS

The prevalence of PD and dysphagia in patients with PD increased continuously during the study period and was highest in the ninth decade of life. The percentage of patients with dysphagia in patients with PD increased with age. Patients with PD showed an adjusted hazard ratio of 3.132 (2.955-3.320) for dysphagia compared to those without PD.

CONCLUSION

This nationwide study showed increasing trends in the prevalence of PD and dysphagia among patients with PD in Korea between 2006 and 2015. The risk of dysphagia was three times higher in patients with PD than that in those without PD, highlighting the importance of providing particular attention.

Attitude Toward Telerehabilitation Among Physical and Occupational Therapists in Korea: A Brief Descriptive Report

The attitude toward telerehabilitation (TR) among therapists (191 physical therapists and 159 occupational therapists) in Korea was surveyed. The survey consisted of 15 questions in the following 8 domains: awareness(AW), attitude (AT), perceived usefulness (PU), perceived behavioral control (PBC), self-efficacy (SE), facilitating conditions (FC), barriers (B), and behavioral intention (BI). Therapists with experience in TR responded with higher scores in all domains except B, regardless of their specialty. The most perceived barriers to TR were unmatched insurance fees and a lack of technical support. Experience with TR was a major factor in attitude and behavior intention toward TR.

The effect of a telephone-based intervention on physical activity after stroke

Despite the effectiveness of telephone-based interventions for medical adherence and improved blood pressure, studies on the effect of such interventions on physical activity (PA) are needed. Therefore, we investigated the impact of a telephone-based intervention on PA in patients with subacute stroke. This pre-post study included patients who participated in an education program for stroke rehabilitation before being discharged to home, with a modified Rankin scale (mRS) score of ≤ 3. Patients hospitalized in 2020 (intervention group) received a nurse-led telephone-based intervention with a PA measurement once monthly during the 3 months after discharge. Those hospitalized in 2019 (historical controls) only received a PA measurement 3 months after discharge. Physical activity was assessed via a questionnaire by phone. In addition, demographics, medical history, smoking, mRS scores, and Patient Health Questionnaire-9 data were collected. The study included 139 participants (73 in intervention, 66 in control). The intervention group had a higher proportion of patients with mRS of 0-1 and a shorter length of hospital stay than the historical controls. Three months post-discharge, a significantly higher proportion of participants were physically active in the intervention group (48 [71.6%] vs. control group, 25 [34.7%]). In addition, the intervention group had a significantly higher median energy expenditure (924 vs. 297 MET-min/week) than the control group. The OR of the intervention for achieving 'physically active' individuals was 4.749 (95% CI, 2.313-9.752) before and 5.222 (95% CI, 1.892-14.419) after adjusting for possible confounders. A telephone-based intervention improved PA three months after stroke. Further studies with larger sample size and long-term follow-up are needed.

Editor's Choice - Effect of Physical Activity and Tobacco Use on Mortality and Morbidity in Patients with Peripheral Arterial Disease After Revascularisation: A Korean Nationwide Population Based Cohort Study

OBJECTIVE

To investigate the effects of physical activity (PA) and tobacco use on adverse clinical outcomes after revascularisation for peripheral arterial disease (PAD) in the Western Pacific region, where PAD cases and tobacco use are among the highest in the world.

METHODS

This was a retrospective cohort study using the Korean National Health Insurance Service (NHIS) database and included patients who had received revascularisation for PAD between 2010 and 2015. They were categorised as active or inactive based on the number of days per week they engaged in PA and as current or non-tobacco users (self report). The primary outcome was all cause mortality. Secondary outcomes included major adverse outcome (a composite of all cause mortality, myocardial infarction, and stroke) and major adverse limb event (MALE, a composite of amputation and recurrent revascularisation).

RESULTS

The relatively healthy cohort comprised 8 324 patients (mean age 64.7 years; 76.9% male) following revascularisation for PAD. Among them, 32.7% were inactive and 26.4% were tobacco users. Active patients had better outcomes than inactive patients (all cause mortality adjusted hazard ratio [adjHR] 0.766; 95% CI 0.685 - 0.855, major adverse outcome adjHR 0.795; 95% CI 0.719 - 0.878, MALE adjHR 0.858; 95% CI 0.773 - 0.953). Tobacco users had poorer outcomes than non-users (all cause mortality adjHR 1.279; 95% CI 1.124 - 1.456, major adverse outcome adjHR 1.263; 95% CI 1.124 - 1.418, MALE adjHR 1.291; 95% CI 1.143 - 1.458).

CONCLUSION

Even after receiving revascularisation for PAD, a sizable proportion of patients were physically inactive and used tobacco, leading to adverse clinical outcomes such as death, cardiovascular morbidity, and amputation in Korea. These modifiable risk factors should be addressed systematically, and a comprehensive approach including supervised exercise programmes and tobacco cessation is needed in patients with PAD.

White matter tracts involved in subcortical unilateral spatial neglect in subacute stroke

Background

Unilateral spatial neglect (USN) is common and associated with poor motor and cognitive outcomes as well as impaired quality of life following stroke. Traditionally, the neural substrates underlying USN have been thought to be cortical areas, such as the posterior parietal cortex. However, patients with stroke involving only subcortical structures may also present with USN. While only a few studies have reported on USN in subcortical stroke, the involvement of white matter tracts related to brain networks of visuospatial attention is one possible explanation for subcortical neglect. Therefore, this study aimed to investigate which specific white matter tracts are neural substrates for USN in patients with subcortical stroke.

Methods

Twenty-two patients with subcortical stroke without cortical involvement who were admitted to the Department of Rehabilitation Medicine at Seoul National University Bundang Hospital were retrospectively enrolled. Nine subjects were subclassified into a “USN(+)” group, as they had at least two positive results on three tests (the Schenkenberg line bisection test, Albert's test, and house drawing test) and a score of 1 or higher on the Catherine Bergego scale. The remaining 13 subjects without abnormalities on those tests were subclassified into the “USN(–)” group. Stroke lesions on MRI were manually drawn using MRIcron software. Lesion overlapping and atlas-based analyses of MRI images were conducted. The correlation was analyzed between the overlapped lesion volumes with white matter tracts and the severity of USN (in the Albert test and the Catherine Bergego scale).

Results

Lesions were more widespread in the USN(+) group than in the USN(–) group, although their locations in the right hemisphere were similar. The atlas-based analyses identified that the right cingulum in the cingulate cortex, the temporal projection of the superior longitudinal fasciculus, and the forceps minor significantly overlapped with the lesions in the USN(+) group than in the USN(–) group. The score of the Catherine Bergego scale correlated with the volume of the involved white matter tracts.

Conclusion

In this study, white matter tracts associated with USN were identified in patients with subcortical stroke without any cortical involvement. Our study results, along with previous findings on subcortical USN, support that USN may result from damage to white matter pathways.

ADC Histogram Analysis of Pediatric Low-Grade Glioma Treated with Selumetinib: A Report from the Pediatric Brain Tumor Consortium

BACKGROUND AND PURPOSE

Selumetinib is a promising MAP (mitogen-activated protein) kinase (MEK) 1/2 inhibitor treatment for pediatric low-grade gliomas. We hypothesized that MR imaging-derived ADC histogram metrics would be associated with survival and response to treatment with selumetinib.

MATERIALS AND METHODS

Children with recurrent, refractory, or progressive pediatric low-grade gliomas who had World Health Organization grade I pilocytic astrocytoma with KIAA1549-BRAF fusion or the BRAF V600E mutation (stratum 1), neurofibromatosis type 1-associated pediatric low-grade gliomas (stratum 3), or sporadic non-neurofibromatosis type 1 optic pathway and hypothalamic glioma (OPHG) (stratum 4) were treated with selumetinib for up to 2 years. Quantitative ADC histogram metrics were analyzed for total and enhancing tumor volumes at baseline and during treatment.

RESULTS

Each stratum comprised 25 patients. Stratum 1 responders showed lower values of SD of baseline ADC_total as well as a larger decrease with time on treatment in ADC_total mean, mode, and median compared with nonresponders. Stratum 3 responders showed a greater longitudinal decrease in ADC_total. In stratum 4, higher baseline ADC_total skewness and kurtosis were associated with shorter progression-free survival. When all 3 strata were combined, responders showed a greater decrease with time in ADC_total mode and median. Compared with sporadic OPHG, neurofibromatosis type 1-associated OPHG had lower values of ADC_total mean, mode, and median as well as ADC_enhancement mean and median and higher values of ADC_total skewness and kurtosis at baseline. The longitudinal decrease in ADC_total median during treatment was significantly greater in sporadic OPHG compared with neurofibromatosis type 1-associated OPHG.

CONCLUSIONS

ADC histogram metrics are associated with progression-free survival and response to treatment with selumetinib in pediatric low-grade gliomas.

Differential activation mechanisms of two isoforms of Gcr1 transcription factor generated from spliced and un-spliced transcripts in Saccharomyces cerevisiae

Gcr1, an important transcription factor for glycolytic genes in Saccharomyces cerevisiae, was recently revealed to have two isoforms, Gcr1^U and Gcr1^S, produced from un-spliced and spliced transcripts, respectively. In this study, by generating strains expressing only Gcr1^U or Gcr1^S using the CRISPR/Cas9 system, we elucidate differential activation mechanisms of these two isoforms. The Gcr1^U monomer forms an active complex with its coactivator Gcr2 homodimer, whereas Gcr1^S acts as a homodimer without Gcr2. The USS domain, 55 residues at the N-terminus existing only in Gcr1^U, inhibits dimerization of Gcr1^U and even acts in trans to inhibit Gcr1^S dimerization. The Gcr1^S monomer inhibits the metabolic switch from fermentation to respiration by directly binding to the ALD4 promoter, which can be restored by overexpression of the ALD4 gene, encoding a mitochondrial aldehyde dehydrogenase required for ethanol utilization. Gcr1^U and Gcr1^S regulate almost the same target genes, but show unique activities depending on growth phase, suggesting that these isoforms play differential roles through separate activation mechanisms depending on environmental conditions.

MRI Features May Predict Molecular Features of Glioblastoma in Isocitrate Dehydrogenase Wild-Type Lower-Grade Gliomas

BACKGROUND AND PURPOSE

Isocitrate dehydrogenase (IDH) wild-type lower-grade gliomas (histologic grades II and III) with epidermal growth factor receptor (EGFR) amplification or telomerase reverse transcriptase (TERT) promoter mutation are reported to behave similar to glioblastoma. We aimed to evaluate whether MR imaging features could identify a subset of IDH wild-type lower-grade gliomas that carry molecular features of glioblastoma.

MATERIALS AND METHODS

In this multi-institutional retrospective study, pathologically confirmed IDH wild-type lower-grade gliomas from 2 tertiary institutions and The Cancer Genome Atlas constituted the training set (institution 1 and The Cancer Genome Atlas, 64 patients) and the independent test set (institution 2, 57 patients). Preoperative MRIs were analyzed using the Visually AcceSAble Rembrandt Images and radiomics. The molecular glioblastoma status was determined on the basis of the presence of EGFR amplification and TERT promoter mutation. Molecular glioblastoma was present in 73.4% and 56.1% in the training and test sets, respectively. Models using clinical, Visually AcceSAble Rembrandt Images, and radiomic features were built to predict the molecular glioblastoma status in the training set; then they were validated in the test set.

RESULTS

In the test set, a model using both Visually AcceSAble Rembrandt Images and radiomic features showed superior predictive performance (area under the curve = 0.854) than that with only clinical features or Visually AcceSAble Rembrandt Images (areas under the curve = 0.514 and 0.648, respectively; P < . 001, both). When both Visually AcceSAble Rembrandt Images and radiomics were added to clinical features, the predictive performance significantly increased (areas under the curve = 0.514 versus 0.863, P < .001).

CONCLUSIONS

MR imaging features integrated with machine learning classifiers may predict a subset of IDH wild-type lower-grade gliomas that carry molecular features of glioblastoma.

Involvement of the Olfactory Apparatus by Gliomas

The olfactory bulbs and tracts are central nervous system white matter tracts maintained by central neuroglia. Although rare, gliomas can originate from and progress to involve the olfactory apparatus. Through a Health Insurance Portability and Accountability Act-compliant retrospective review of the institutional teaching files and brain MR imaging reports spanning 10 years, we identified 12 cases of gliomas involving the olfactory bulbs and tracts, including 6 cases of glioblastoma, 2 cases of anaplastic oligodendroglioma, and 1 case each of pilocytic astrocytoma, diffuse (grade II) astrocytoma, anaplastic astrocytoma (grade III), and diffuse midline glioma. All except the pilocytic astrocytoma occurred in patients with known primary glial tumors elsewhere. Imaging findings of olfactory tumor involvement ranged from well-demarcated enhancing masses to ill-defined enhancing infiltrative lesions to nonenhancing masslike FLAIR signal abnormality within the olfactory tracts. Familiarity with the imaging findings of glioma involvement of the olfactory nerves is important for timely diagnosis and treatment of recurrent gliomas and to distinguish them from other disease processes.

High prevalence of physical inactivity after heart valve surgery and its association with long-term mortality: A nationwide cohort study

AIMS

Physical activity (PA) and systematic efforts, such as cardiac rehabilitation, are recommended by several national guidelines for those who have received heart valve surgery. However, only a few studies have demonstrated real-world situations, such as changes in the PA level after heart valve surgery, and their effects on long-term outcomes. We designed this study to investigate the changes in PA after heart valve surgery and their associations with mortality using nationwide representative data.

METHODS

This study was performed using the Korean National Health Insurance Service database. We included patients who received heart valve surgery from 2009 to 2015 and underwent regular health checkups before and after surgery. Subjects were grouped according to their PA level before and after the surgery. Information on all-cause mortality was obtained until 31 December 2016, with a maximum follow-up period of 5 years.

RESULTS

Of the 6587 subjects, 3258 (49.5%) were physically inactive after surgery. Among patients who were physically active (n = 3070), 1196 (39.0%) became inactive after surgery. The postoperative 'inactive' group showed higher mortality than the 'active' group (hazard ratio (HR): 1.41, 95% confidence interval (CI): 1.08-1.83). The 'inactive/inactive' group showed the highest risk of mortality (HR: 1.69, 95% CI: 1.19-2.40) compared with the 'active/active' group.

CONCLUSIONS

Insufficient PA level after heart valve surgery is associated with higher risk of mortality. However, maintaining sufficient PA after heart valve surgery may be challenging for many patients. Therefore, systematic efforts, such as cardiac rehabilitation, should be considered in those who received heart valve surgery.

Diffusion Characteristics of Pediatric Diffuse Midline Gliomas with Histone H3-K27M Mutation Using Apparent Diffusion Coefficient Histogram Analysis

BACKGROUND AND PURPOSE

Diffuse midline gliomas with histone H3 K27M mutation are biologically aggressive tumors with poor prognosis defined as a new diagnostic entity in the 2016 World Health Organization Classification of Tumors of the Central Nervous System. There are no qualitative imaging differences (enhancement, border, or central necrosis) between histone H3 wildtype and H3 K27M-mutant diffuse midline gliomas. Herein, we evaluated the utility of diffusion-weighted imaging to distinguish H3 K27M-mutant from histone H3 wildtype diffuse midline gliomas.

MATERIALS AND METHODS

We identified 31 pediatric patients (younger than 21 years of age) with diffuse gliomas centered in midline structures that had undergone assessment for histone H3 K27M mutation. We measured ADC within these tumors using a voxel-based 3D whole-tumor measurement method.

RESULTS

Our cohort included 18 infratentorial and 13 supratentorial diffuse gliomas centered in midline structures. Twenty-three (74%) tumors carried H3-K27M mutations. There was no difference in ADC histogram parameters (mean, median, minimum, maximum, percentiles) between mutant and wild-type tumors. Subgroup analysis based on tumor location also did not identify a difference in histogram descriptive statistics. Patients who survived <1 year after diagnosis had lower median ADC (1.10 × 10^-3mm²/s; 95% CI, 0.90-1.30) compared with patients who survived >1 year (1.46 × 10^-3mm²/s; 95% CI, 1.19-1.67; P < .06). Average ADC values for diffuse midline gliomas were 1.28 × 10^-3mm²/s (95% CI, 1.21-1.34) and 0.86 × 10^-3mm²/s (95% CI, 0.69-1.01) for hemispheric glioblastomas with P < .05.

CONCLUSIONS

Although no statistically significant difference in diffusion characteristics was found between H3-K27M mutant and H3 wildtype diffuse midline gliomas, lower diffusivity corresponds to a lower survival rate at 1 year after diagnosis. These findings can have an impact on the anticipated clinical course for this patient population and offer providers and families guidance on clinical outcomes.

A framework for automated conflict detection and resolution in medical guidelines

Common chronic conditions are routinely treated following standardised procedures known as clinical guidelines. For patients suffering from two or more chronic conditions, known as multimorbidity, several guidelines have to be applied simultaneously, which may lead to severe adverse effects when the combined recommendations and prescribed medications are inconsistent or incomplete. This paper presents an automated formal framework to detect, highlight and resolve conflicts in the treatments used for patients with multimorbidities focusing on medications. The presented extended framework has a front-end which takes guidelines captured in a standard modelling language and returns the visualisation of the detected conflicts as well as suggested alternative treatments. Internally, the guidelines are transformed into formal models capturing the possible unfoldings of the guidelines. The back-end takes the formal models associated with multiple guidelines and checks their correctness with a theorem prover, and inherent inconsistencies with a constraint solver. Key to our approach is the use of an optimising constraint solver which enables us to search for the best solution that resolves/minimises conflicts according to medication efficacy and the degree of severity in case of harmful combinations, also taking into account their temporal overlapping. The approach is illustrated throughout with a real medical example.

Effect of an Inpatient Rehabilitation Program for Recovery of Deconditioning in Hematologic Cancer Patients After Chemotherapy

OBJECTIVE

To investigate the effect of a rehabilitation program in terms of De Morton Mobility Index (DEMMI) score, in hematologic cancer patients after chemotherapy.

METHODS

Hematologic cancer patients admitted for chemotherapy were reviewed. They received a rehabilitation program during their hospital stay. DEMMI score measurement was performed, before and after rehabilitation. Demographics, diagnosis, chemotherapy information, rehabilitation program duration, mortality, body mass index (BMI), and laboratory test results were collected. For analysis, patients were classified according to diagnosis (multiple myeloma, leukemia, and others), mortality, and additional chemotherapy.

RESULTS

There was statistically significant improvement in DEMMI score of 10.1 points (95% confidence interval, 5.9-14.3) after rehabilitation. It was more evident in the multiple myeloma group, and they revealed less mortality. When patients were divided according to mortality, survivors received the program earlier, and in a shorter period than in mortality cases. Although survivors revealed higher initial DEMMI score, improvement after rehabilitation did not differ significantly.

CONCLUSION

In hematologic cancer patients, rehabilitation program was effective for recovery from deconditioning, revealing significant increase in DEMMI score. Multiple myeloma patients may be good candidates for rehabilitation. Rehabilitation could be sustained during chemotherapy and for high-risk patients.

Efficient production of d-lactate from methane in a lactate-tolerant strain of Methylomonas sp. DH-1 generated by adaptive laboratory evolution

BACKGROUND

Methane, a main component of natural gas and biogas, has gained much attention as an abundant and low-cost carbon source. Methanotrophs, which can use methane as a sole carbon and energy source, are promising hosts to produce value-added chemicals from methane, but their metabolic engineering is still challenging. In previous attempts to produce lactic acid (LA) from methane, LA production levels were limited in part due to LA toxicity. We solved this problem by generating an LA-tolerant strain, which also contributes to understanding novel LA tolerance mechanisms.

RESULTS

In this study, we engineered a methanotroph strain Methylomonas sp. DH-1 to produce d-lactic acid (d-LA) from methane. LA toxicity is one of the limiting factors for high-level production of LA. Therefore, we first performed adaptive laboratory evolution of Methylomonas sp. DH-1, generating an LA-tolerant strain JHM80. Genome sequencing of JHM80 revealed the causal gene watR, encoding a LysR-type transcription factor, whose overexpression due to a 2-bp (TT) deletion in the promoter region is partly responsible for the LA tolerance of JHM80. Overexpression of the watR gene in wild-type strain also led to an increase in LA tolerance. When d form-specific lactate dehydrogenase gene from Leuconostoc mesenteroides subsp. mesenteroides ATCC 8293 was introduced into the genome while deleting the glgA gene encoding glycogen synthase, JHM80 produced about 7.5-fold higher level of d-LA from methane than wild type, suggesting that LA tolerance is a critical limiting factor for LA production in this host. d-LA production was further enhanced by optimization of the medium, resulting in a titer of 1.19 g/L and a yield of 0.245 g/g CH₄.

CONCLUSIONS

JHM80, an LA-tolerant strain of Methylomonas sp. DH-1, generated by adaptive laboratory evolution was effective in LA production from methane. Characterization of the mutated genes in JHM80 revealed that overexpression of the watR gene, encoding a LysR-type transcription factor, is responsible for LA tolerance. By introducing a heterologous lactate dehydrogenase gene into the genome of JHM80 strain while deleting the glgA gene, high d-LA production titer and yield were achieved from methane.

Spasticity and preservation of skeletal muscle mass in people with spinal cord injury

STUDY DESIGN

Cross-sectional OBJECTIVE: To investigate the association between skeletal muscle mass and spasticity in people with spinal cord injury (SCI).

SETTING

Tertiary level hospital in Seoul, Korea METHODS: Spasticity was evaluated in 69 participants with SCI using the spasticity sum score (SSS), Penn Spasm Frequency Scale (PSFS), and Spinal Cord Assessment Tool for Spastic Reflexes (SCATS). Skeletal muscle mass was measured using a dual-energy X-ray absorptiometry scanner, and skeletal muscle index was calculated by dividing skeletal muscle mass by height squared. Laboratory parameters including hemoglobin, albumin, creatinine, fasting glucose, and cholesterol were measured. Spearman's correlation analysis was performed to assess the association between the skeletal muscle mass and spasticity scales. Multiple linear regression analysis was used to present the independent association between them.

RESULTS

The participants' mean age was 41.8 years; 54 (78.3%) were male, and 46 (66.7%) were tetraplegic. Skeletal muscle index of lower extremities was significantly correlated with all spasticity scales. Spearman's correlation coefficients were 0.468, 0.467, 0.555, 0.506, and 0.474 for SSS, PSFS, SCATS clonus, SCATS flexor, and SCATS extensor with p-values < 0.001, respectively. After adjustment for age, sex, level of injury, body mass index, and serum creatinine, all spasticity scales were significantly associated with skeletal muscle index of lower extremities in multiple regression analysis. Standardized coefficients were 0.228, 0.274, 0.294, 0.210, and 0.227 for SSS, PSFS, SCATS clonus, SCATS flexor, and SCATS extensor.

CONCLUSIONS

Spasticity was significantly correlated with the skeletal muscle mass even after adjusting for possible confounders. Spasticity may need to be considered as an influencing factor in interventions such as electrical stimulation to preserve skeletal muscle mass.

Need for Systematic Efforts to Modify Health-Related Behaviors After Acute Myocardial Infarction in Korea

BACKGROUND

Modification of health-related behaviors may improve clinical outcomes after acute myocardial infarction (AMI), but the need for systematic efforts to modify such behaviors and the estimated effect have not been investigated, especially in Asian populations. The aim of the study was to investigate changes in smoking and physical activity after AMI and their associations with death and recurrent revascularization. Methods and Results: Using the Korean National Insurance Health Service database, we included 13,452 patients with AMI in 2011, who were stable until 1.5 years on average after onset. Patients were grouped according to their smoking status and physical activity before and after AMI. After AMI, 44.6% of smokers continued smoking and only 11.0% of inactive patients increased their physical activity to a sufficient level. The 'smoker/smoker' group and 'non-smoker/smoker' group showed higher mortality (hazard ratio (HR): 1.566, 95% confidence interval (CI): 1.192-2.035; HR: 1.785, 95% CI: 1.061-2.815, respectively). On the other hand, the 'active/active' group and 'inactive/active' group showed less mortality (HR: 0.625, 95% CI: 0.460-0.832; HR: 0.681, 95% CI: 0.438-1.009, respectively) and the 'inactive/active' group showed less recurrent revascularization (HR: 0.761, 95% CI: 0.599-0.952).

CONCLUSIONS

Smoking cessation and maintaining sufficient physical activity after AMI remain challenging for many Korean patients, and are associated with higher rates of mortality and recurrent revascularization. Systematic nationwide efforts such as cardiac rehabilitation (CR) to change health-related behaviors after AMI are required in Korea.

Deep-Learning Convolutional Neural Networks Accurately Classify Genetic Mutations in Gliomas

BACKGROUND AND PURPOSE

The World Health Organization has recently placed new emphasis on the integration of genetic information for gliomas. While tissue sampling remains the criterion standard, noninvasive imaging techniques may provide complimentary insight into clinically relevant genetic mutations. Our aim was to train a convolutional neural network to independently predict underlying molecular genetic mutation status in gliomas with high accuracy and identify the most predictive imaging features for each mutation.

MATERIALS AND METHODS

MR imaging data and molecular information were retrospectively obtained from The Cancer Imaging Archives for 259 patients with either low- or high-grade gliomas. A convolutional neural network was trained to classify isocitrate dehydrogenase 1 (IDH1) mutation status, 1p/19q codeletion, and O6-methylguanine-DNA methyltransferase (MGMT) promotor methylation status. Principal component analysis of the final convolutional neural network layer was used to extract the key imaging features critical for successful classification.

RESULTS

Classification had high accuracy: IDH1 mutation status, 94%; 1p/19q codeletion, 92%; and MGMT promotor methylation status, 83%. Each genetic category was also associated with distinctive imaging features such as definition of tumor margins, T1 and FLAIR suppression, extent of edema, extent of necrosis, and textural features.

CONCLUSIONS

Our results indicate that for The Cancer Imaging Archives dataset, machine-learning approaches allow classification of individual genetic mutations of both low- and high-grade gliomas. We show that relevant MR imaging features acquired from an added dimensionality-reduction technique demonstrate that neural networks are capable of learning key imaging components without prior feature selection or human-directed training.

Optimal stimulation parameters for intraoperative bulbocavernosus reflex in infants

OBJECTIVE The aim of this study was to establish optimal electric stimulation parameters for intraoperatively monitoring the bulbocavernosus reflexes (BCRs) in infants. METHODS The authors retrospectively reviewed the medical records of all infants (age < 24 months) who had undergone an untethering operation for tethered cord syndrome between May 2013 and February 2014 at a single institution and whose baseline BCR had been elicited during surgery. Using different combinations of stimulation parameters-number of stimulation pulses: 4 or 8 pulses, interpulse interval: 1, 2, or 5 msec, and polarity of stimulation: biphasic or monophasic-the authors compared the relative mean amplitude of 10 BCR responses (rmaBCRs) to each combination of parameters. RESULTS The rmaBCRs were larger with the 8-pulse stimulations than with the 4-pulse stimulations (p < 0.0001). There was a tendency, though not statistically significant, for larger rmaBCRs to be obtained with the longer interpulse interval in the 8-pulse stimulation (p = 0.1289). The biphasic stimulation produced larger rmaBCRs than the monophasic stimulation (p = 0.0005). CONCLUSIONS Biphasic 8-pulse stimulations with 5-msec or 2-msec intervals yield the largest BCR responses. Considering that an 8-pulse stimulation with 5-msec intervals may overlap the onset of the BCR, a biphasic 8-pulse stimulation with 2-msec intervals is recommended as the optimal stimulation paradigm to monitor intraoperative BCRs in infants.

Differentiation of brain tumor-related edema based on 3D T1rho imaging

BACKGROUND AND PURPOSE

Cerebral edema associated with brain tumors is an important source of morbidity. Its type depends largely on the capillary ultra-structures of the histopathologic subtype of underlying brain tumor. The purpose of our study was to differentiate vasogenic edema associated with brain metastases and infiltrative edema related to diffuse gliomas using quantitative 3D T1 rho (T1ρ) imaging.

MATERIALS AND METHODS

Preoperative MR examination including whole brain 3D T1ρ imaging was performed in 23 patients with newly diagnosed brain tumors (9 with metastasis, 8 with lower grade glioma, LGG, 6 with glioblastoma, GBM). Mean T1ρ values were measured in regions of peritumoral non-enhancing T2 signal hyperintensity, excluding both enhancing and necrotic or cystic component, and normal-appearing white matter.

RESULTS

Mean T1ρ values were significantly elevated in the vasogenic edema surrounding intracranial metastases when compared to the infiltrative edema associated with either LGG or GBM (p=0.02 and <0.01, respectively). No significant difference was noted between T1ρ values of infiltrative edema between LGG and GBM (p=0.84 and 0.96, respectively).

CONCLUSION

Our study demonstrates the feasibility and potential diagnostic role of T1ρ in the quantitative differentiation between edema related to intracranial metastases and gliomas and as a potentially complementary tool to standard MR techniques in further characterizing pathophysiology of vasogenic and infiltrative edema.

Imaging Characteristics of Pediatric Diffuse Midline Gliomas with Histone H3 K27M Mutation

BACKGROUND AND PURPOSE

The 2016 World Health Organization Classification of Tumors of the Central Nervous System includes "diffuse midline glioma with histone H3 K27M mutation" as a new diagnostic entity. We describe the MR imaging characteristics of this new tumor entity in pediatric patients.

MATERIALS AND METHODS

We retrospectively reviewed imaging features of pediatric patients with midline gliomas with or without the histone H3 K27 mutation. We evaluated the imaging features of these tumors on the basis of location, enhancement pattern, and necrosis.

RESULTS

Among 33 patients with diffuse midline gliomas, histone H3 K27M mutation was present in 24 patients (72.7%) and absent in 9 (27.3%). Of the tumors, 27.3% (n = 9) were located in the thalamus; 42.4% (n = 14), in the pons; 15% (n = 5), within the vermis/fourth ventricle; and 6% (n = 2), in the spinal cord. The radiographic features of diffuse midline gliomas with histone H3 K27M mutation were highly variable, ranging from expansile masses without enhancement or necrosis with large areas of surrounding infiltrative growth to peripherally enhancing masses with central necrosis with significant mass effect but little surrounding T2/FLAIR hyperintensity. When we compared diffuse midline gliomas on the basis of the presence or absence of histone H3 K27M mutation, there was no significant correlation between enhancement or border characteristics, infiltrative appearance, or presence of edema.

CONCLUSIONS

We describe, for the first time, the MR imaging features of pediatric diffuse midline gliomas with histone H3 K27M mutation. Similar to the heterogeneous histologic features among these tumors, they also have a diverse imaging appearance without distinguishing features from histone H3 wildtype diffuse gliomas.

The Combined Performance of ADC, CSF CXC Chemokine Ligand 13, and CSF Interleukin 10 in the Diagnosis of Central Nervous System Lymphoma

BACKGROUND AND PURPOSE

CXC chemokine ligand 13 and interleukin 10 have emerged as CSF biomarkers for the diagnosis of CNS lymphoma. Our hypothesis is that the combined use of ADC, CXC chemokine ligand 13, and interleukin 10 will result in increased diagnostic performance compared with the use of ADC values alone.

MATERIALS AND METHODS

Eighty-seven patients were included in this study, including 43 with CNS lymphoma and 44 without CNS lymphoma (21 metastases, 14 high-grade gliomas, 9 tumefactive demyelinating lesions) who had undergone CSF proteomic analysis and had a new enhancing mass on brain MR imaging. Average ADC was derived by contouring the contrast-enhancing tumor volume. Group means were compared via t tests for average ADC, CXC chemokine ligand 13, and interleukin 10. Receiver operating characteristic analysis was performed for each individual variable. Multiple-variable logistic regression with receiver operating characteristic analysis was performed, and the multiple-variable receiver operating characteristic was compared with single-variable receiver operating characteristics.

RESULTS

The average ADC was lower and CSF CXC chemokine ligand 13 and interleukin 10 values were higher in CNS lymphoma (P < .001). Areas under the curve ranged from 0.739 to 0.832 for single-variable ROC. Multiple-variable logistic regression yielded statistically significant individual effects for all 3 variables in a combined model. Multiple-variable receiver operating characteristics (area under the curve, 0.928) demonstrated statistically significantly superior diagnostic performance compared with the use of single variables alone.

CONCLUSIONS

The combined use of ADC, CSF CXC chemokine ligand 13, and interleukin 10 results in increased diagnostic performance for the diagnosis of CNS lymphoma. This finding highlights the importance of CSF analysis when the diagnosis of CNS lymphoma is considered on the basis of MR imaging.