Metabolic tumor burden as a prognostic indicator after neoadjuvant chemotherapy in pancreatic cancer.

BACKGROUND: There is no standardized assessment for evaluating response although neoadjuvant chemotherapy (NAT) is widely accepted for borderline resectable or locally advanced pancreatic cancer (BRPC or LAPC). This study was aimed to evaluate NAT response using positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose ( 18 F-FDG-PET/CT) parameters alongside carbohydrate antigen (CA) 19-9 levels. METHODS: Patients who underwent surgery after NAT for BRPC and LAPC between 2017 and 2021 were identified. The study assessed the prognostic value of PET-derived parameters after NAT, determining cutoff values using the K-adaptive partitioning method. It created four groups based on the elevation or normalization of PET parameters and CA19-9 levels, comparing survival between these groups. RESULTS: Of 200 eligible patients, FOLFIRINOX and gemcitabine-based NAT were administered in 167 and 34 patients, respectively (mean NAT cycles, 8.3). In a multivariate analysis, metabolic tumor volume (MTV) demonstrated the most robust performance in assessing response (HR 3.11, 95% CI 1.73-5.58, P <0.001) based on cut-off value of 2.4. Patients with decreased MTV had significantly better survival than those with elevated MTV among individuals with CA19-9 levels <37 IU/L (median survival; 35.5 vs. 20.9 mo, P <0.001) and CA19-9 levels ≥37 IU/L (median survival; 34.3 vs. 17.8 mo, P =0.03). In patients suspected to be Lewis antigen negative, predictive performance of MTV was found to be limited ( P =0.84). CONCLUSION: Elevated MTV is an influential prognostic factor for worse survival, regardless of post-NAT CA19-9 levels. These results could be helpful in identifying patients with a poor prognosis despite normalization of CA19-9 levels after NAT.

Three months-longitudinal changes in relative telomere length, blood chemistries, and self-report questionnaires in meditation practitioners compared to novice individuals during midlife.

Aging accelerates during midlife. Researches have shown the health benefits of mind-body intervention (MBI). However, whether MBI is involved with aging process has not been well understood. In this study, we approach to examine the relations of MBI with this process by investigating an aging marker of the peripheral blood, blood chemistry, and self-report questionnaires. A quasi-experimental design was applied. Experienced MBI practitioners participated in a 3-month intensive meditation training, while the age, gender-matched MBI-naïve controls led a normal daily life. Measurements were taken at before and after the 3 months for relative telomere length (RTL), blood chemistry, and self-report questionnaires including items about sleep quality, somatic symptoms, depression, anxiety, stress, emotional intelligence (EI), and self-regulation. For RTL, the repeated measures analysis of variance showed a significant group*time interaction (P = .013) with a significant post hoc result (P = .030) within the control group: RTL was significantly reduced in the control while it was maintained in the meditation group. In repeated measures analysis of variance for blood chemistries, there were significant group differences between the groups in glucose and total protein. In the post hoc comparison analysis, at post measurements, the meditation group exhibited significantly lower values than the control group in both glucose and total protein. There were significant group-wise differences in the correlations of RTL with triglyceride (TG), high-density lipoprotein (HDL), glutamic oxaloacetic transaminase and glutamic pyruvic transaminase. Any of self-report results did not show significant changes in group*time interaction. However, there were group differences with significant (P < .05) or a tendency (.05 < P < .1) level. There were significant improvements in depression, stress and EI as well as tendencies of improvement in sleep quality and anxiety, in the meditation group compared to the control group. Our results suggest that meditation practice may have a potential to modify aging process in molecular cellular level combined with changes in psychological dimension.

RoF-based indoor distributed antenna system that can simultaneously support 5G mmWave and 6G terahertz services.

The telecommunication society is paving the way toward ultra-high frequency regions, including the millimeter wave (mmWave) and sub-terahertz (sub-THz) bands. Such high-frequency electromagnetic waves induce a variety of physical constraints when they are used in wireless communications. Inevitably, the fiber-optic network is deeply embedded in the mobile network to resolve such challenges. In particular, the radio-over-fiber (RoF)-based distributed antenna system (DAS) can enhance the accessibility of next-generation mobile networks. The inherent benefits of RoF technology enhance the DAS network in terms of practicality and transmission performance by enabling it to support the 5G mmWave and 6G THz services simultaneously in a single optical transport link. Furthermore, the RoF allows the indoor network to be built based on the cascade architecture; thus, a service zone can be easily added on request. This study presents an RoF-based multi-service DAS network and experimentally investigates the feasibility of the proposed system.

Preoperative serum carbohydrate antigen 19-9 levels predict early recurrence after the resection of early-stage pancreatic ductal adenocarcinoma.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a serious disease with a poor prognosis. Only a minority of patients undergo surgery due to the advanced stage of the disease, and patients with early-stage disease, who are expected to have a better prognosis, often experience recurrence. Thus, it is important to identify the risk factors for early recurrence and to develop an adequate treatment plan. AIM: To evaluate the predictive factors associated with the early recurrence of early-stage PDAC. METHODS: This study enrolled 407 patients with stage I PDAC undergoing upfront surgical resection between January 2000 and April 2016. Early recurrence was defined as a diagnosis of recurrence within 6 mo of surgery. The optimal cutoff values were determined by receiver operating characteristic (ROC) analyses. Univariate and multivariate analyses were performed to identify the risk factors for early recurrence. RESULTS: Of the 407 patients, 98 patients (24.1%) experienced early disease recurrence: 26 (26.5%) local and 72 (73.5%) distant sites. In total, 253 (62.2%) patients received adjuvant chemotherapy. On ROC curve analysis, the optimal cutoff values for early recurrence were 70 U/mL and 2.85 cm for carbohydrate antigen 19-9 (CA 19-9) levels and tumor size, respectively. Of the 181 patients with CA 19-9 level > 70 U/mL, 59 (32.6%) had early recurrence, compared to 39 (17.4%) of 226 patients with CA 19-9 level ≤ 70 U/mL (P < 0.001). Multivariate analysis revealed that CA 19-9 level > 70 U/mL (P = 0.006), tumor size > 2.85 cm (P = 0.004), poor differentiation (P = 0.008), and non-adjuvant chemotherapy (P = 0.025) were significant risk factors for early recurrence in early-stage PDAC. CONCLUSION: Elevated CA 19-9 level (cutoff value > 70 U/mL) can be a reliable predictive factor for early recurrence in early-stage PDAC. As adjuvant chemotherapy can prevent early recurrence, it should be recommended for patients susceptible to early recurrence.

A cross-sectional study on the relationship between meditation training and emotional intelligence in women.

AIM: We aimed to reveal the relationship of meditation with emotional intelligence (EI), sleep quality and melatonin level. DESIGN: A cross-sectional study. METHODS: Our current research was performed on middle-aged women. EI scale, Pittsburgh Sleep Quality Index (PSQI) and night-time saliva melatonin were measured for 65 participants including 33 meditators and 32 controls. RESULTS: The meditation group showed a significantly higher EI score than the control group. In the regression analysis between EI and age, only the meditation group showed a significant positive correlation. The Pearson correlation analysis among all participants revealed a significant negative correlation between PSQI and EI. There was no significant group difference in the melatonin and PSQI.

Changes Induced by Mind-Body Intervention Including Epigenetic Marks and Its Effects on Diabetes.

Studies have evidenced that epigenetic marks associated with type 2 diabetes (T2D) can be inherited from parents or acquired through fetal and early-life events, as well as through lifelong environments or lifestyles, which can increase the risk of diabetes in adulthood. However, epigenetic modifications are reversible, and can be altered through proper intervention, thus mitigating the risk factors of T2D. Mind-body intervention (MBI) refers to interventions like meditation, yoga, and qigong, which deal with both physical and mental well-being. MBI not only induces psychological changes, such as alleviation of depression, anxiety, and stress, but also physiological changes like parasympathetic activation, lower cortisol secretion, reduced inflammation, and aging rate delay, which are all risk factors for T2D. Notably, MBI has been reported to reduce blood glucose in patients with T2D. Herein, based on recent findings, we review the effects of MBI on diabetes and the mechanisms involved, including epigenetic modifications.

A potential association of meditation with menopausal symptoms and blood chemistry in healthy women: A pilot cross-sectional study.

Owing to hormonal changes, women experience various psychophysiological alterations over a wide age range, which may result in decreased quality of life as well as in increased risks of diseases, such as cardiovascular diseases. Although studies have been performed to research complementary methods, such as meditation, the research field still requires an adequate amount of studies for public health guidelines. This pilot cross-sectional study aims to investigate a potential association of meditation with menopausal symptoms and blood chemistry for healthy women. In this study, data of 65 healthy women (age range 25-67) including 33 meditation practitioners and 32 meditation-naïve controls were analyzed to compare the Menopausal Rating Scale scores and blood chemistry with 7 more dropouts in the blood chemistry. For blood chemistry, nine components including glucose (GLU) and high-density lipoprotein cholesterol (HDL) were measured. Two-way analysis of variance was performed by dividing the total participants into 2 groups: premenopausal and postmenopausal participants. Compared to the control group, the meditation group showed a trend of reductions in the Menopausal Rating Scale total score (P = .054) and its 2 subcomponents: depressive mood (P = .064) and irritability (P = .061). In HDL level, there was a significant interaction between group and menopausal state (P = .039) with following post hoc results: among the premenopausal participants, a significant increase in the meditation group compared to the control group (P = .005); among the control group, a significant increase in the postmenopausal compared to the premenopausal participants (P = .030). In GLU level, there was a mild interaction between group and menopausal state (P = .070) with following post hoc results: among the postmenopausal participants, a trend of increase in the control group compared to the meditation group (P = .081); among the control group, a significant increase in the postmenopausal compared to the premenopausal participants (P = .040). Our research suggests a potential association of practicing meditation with alleviations in menopausal symptoms and changes in blood chemistry, warranting further studies with a longitudinal study design and larger populations to understand the underlying causal relationships.

Meditative Movement Affects Working Memory Related to Neural Activity in Adolescents: A Randomized Controlled Trial.

Numerous studies have revealed that meditative movement changes brain activity and improves the cognitive function of adults. However, there is still insufficient data on whether meditative movement contributes to the cognitive function of adolescents whose brain is still under development. Therefore, this study aimed to uncover the effects of meditative movement on the cognitive performance and its relation with brain activity in adolescents. Forty healthy adolescent participants (mean age of 17∼18) were randomly allocated into two groups: meditative movement and control group. The meditative movement group was instructed to perform the meditative movement, twice a day for 9 min each, for a duration of 3 weeks. During the same time of the day, the control group was instructed to rest under the same condition. To measure changes in cognitive abilities, a dual n-back task was performed before and after the intervention and analyzed by repeated two-way analysis of variance (ANOVA). During the task, electroencephalogram signals were collected to find the relation of brain activity with working memory performance and was analyzed by regression analysis. A repeated two-way ANOVA with Bonferroni correction showed that working memory performance was significantly increased by meditative movement compared with the retest effect. Based on regression analysis, the amplitude of high-beta rhythm in the F3 channel showed a significant correlation with dual n-back score in the experimental group after the intervention, while there was no correlation in the control group. Our results suggest that meditative movement improves the performance of working memory, which is related to brain activity in adolescents. Clinical Trial Registration: cris.nih.go.kr/cris, identifier KCT0004706.

4 × 4 MIMO architecture supporting IFoF-based analog indoor distributed antenna system for 5G mobile communications.

We demonstrate the analog indoor distributed antenna system (DAS) for 5G mobile communications that supports 4 × 4 multiple-input multiple-output (MIMO) configuration. For this, we exploit a pair of intermediate frequency over fiber (IFoF)-based analog optical links, transporting 32 frequency allocation (FA) 5G mobile signals (effectively ~4 GHz bandwidth). The analog optical link manifests its high fidelity in the measured characteristics: small gain variation (< ± 1 dB for the entire transmission bandwidth), low noise (<-136 dBm/Hz), and large dynamic range (spurious free dynamic range of >106 dB∙Hz2/3), subsequently providing superior error vector magnitude (EVM) performance (~2%) for a wide range of ambient temperatures (-20 ~60°C). Consequently, the IFoF-based 4 × 4 MIMO supporting analog indoor DAS is capable of providing record high peak throughput of 5.3 Gb/s for millimeter wave based 5G mobile communication system.

Investigation of transmission performance in multi-IFoF based mobile fronthaul with dispersion-induced intermixing noise mitigation.

We demonstrate the improvement of the transmission performance based on intermixing noise mitigation techniques in a multiple intermediate-frequency-over-fiber (IFoF) based mobile fronthaul. The interaction between fiber chromatic dispersion and frequency chirp of the directly modulated laser generates the second-order distortion that degrades the performance of multi-IFoF transmission system. To avoid second-order distortion, we use intermediate frequency (IF) spacing optimization and octave-confined frequency plan schemes in which intermixing noise would be generated in the out of signal band and would not affect the quality of transmitted signal. For bandwidth efficient transmission of radio signal over mobile fronthaul link, we employ the dispersion compensation technique to suppress the intermixing noise sufficiently. For realization of the multi-IFoF based mobile fronthaul, we experimentally investigate the transmission performances of 48-, 72- and 144-IF carriers of the long term evolution-advanced (LTE-A) signals mapped with 64-quadrature amplitude modulation (QAM). It is clearly observed that the intermixing noise is suppressed owing to dispersion compensation technique and overall system performances are improved by IF spacing optimization and octave-confined frequency plan. As a result, we successfully transmit 144-IF carriers of the LTE-A signal with less than 8% error vector magnitude (EVM) over 20-km single-mode fiber (SMF) within only 3 GHz bandwidth.

Improvement of the transmission performance in multi-IF-over-fiber mobile fronthaul by using tone-reservation technique.

We demonstrate the improvement of the transmission performance based on tone-reservation technique in a multiple intermediate-frequency-over-fiber (IFoF) based mobile fronthaul. The tone-reservation technique can suppress nonlinear distortion by eliminating the high peak components of orthogonal frequency-division multiplexing (OFDM) signal. To prevent the regrowth of peak, we employ tone-reservation after multiplexing IF carriers. Furthermore, we use an out-of-band signal as the reserved tones to avoid any modification of a mobile signal. The impact of the number of IF carriers on peak-to-average power ratio (PAPR) characteristics is presented via numerical simulation. For the multi-IFoF based mobile fronthaul, we experimentally investigate the transmission performance of 36-IF carriers of the long term evolution-advanced (LTE-A) signals mapped with 64-quadrature amplitude modulation (QAM). It is clearly observed that the clipping-induced nonlinear distortion is dramatically suppressed by using tone-reservation. As a result, the transmission performance of 36-IF carriers of the LTE-A signal is improved by an error-vector-magnitude (EVM) of 4% (from 9.7% to 5.7%) after 20-km transmission.

Improvement of the chromatic dispersion tolerance in coherent optical OFDM systems using shifted DFT windows for ultra-long-haul optical transmission systems.

In a high-capacity ultra-long-haul optical coherent orthogonal frequency-division multiplexing (CO-OFDM) system, the dispersion tolerance is determined by the length of cyclic extension (CE). In this paper, we propose a novel scheme to substantially improve the dispersion tolerance of CO-OFDM systems without increasing the CE length. Multiple time-shifted discrete Fourier transform (DFT) windows are exploited at the receiver, each demodulating only a part of the subcarriers. Effectively, the proposed scheme reduces the bandwidth of the OFDM signals under demodulation. Numerical simulations are performed to show the improved dispersion tolerance of the proposed scheme in comparison with the conventional CO-OFDM system. We show that the dispersion tolerance improves by a factor equal to the number of DFT windows. The tradeoff between the improved dispersion tolerance and increased receiver complexity is also presented.