Culturing at Low Cell Density Delays Cellular Senescence of Human Bone Marrow-Derived Mesenchymal Stem Cells in Long-Term Cultures

Background and Objectives

Mesenchymal stem cells (MSCs) have immense therapeutic potential for treating intractable and immune diseases. They also have applications in regenerative medicine in which distinct treatments do not exist. Thus, MSCs are gaining attention as important raw materials in the field of cell therapy. Importantly, the number of MSCs in the bone marrow is limited and they are present only in small quantities. Therefore, mass production of MSCs through long-term culture is necessary to use them in cell therapy. However, MSCs undergo cellular senescence through repeated passages during mass production. In this study, we explored methods to prolong the limited lifetime of MSCs by culturing them with different seeding densities.

Methods and Results

We observed that in long-term cultures, low-density (LD, 50 cells/cm²) MSCs showed higher population doubling level, leading to greater fold increase, than high-density (HD, 4,000 cells/cm²) MSCs. LD-MSCs suppressed the expression of aging-related genes. We also showed that reactive oxygen species (ROS) were decreased in LD-MSCs compared to that in HD-MSCs. Further, proliferation potential increased when ROS were inhibited in HD-MSCs.

Conclusions

The results in this study suggest that MSC senescence can be delayed and that life span can be extended by controlling cell density in vitro. These results can be used as important data for the mass production of stem cell therapeutic products.

Electromechanical Response of Smart Ultra-High Performance Concrete under External Loads Corresponding to Different Electrical Measurements

This study investigated the electromechanical response of smart ultra-high-performance concretes (smart UHPCs), containing fine steel slag aggregates (FSSAs) and steel fibers as functional fillers, under external loads corresponding to different measurement methods. Regardless of different measurement methods of electrical resistance, the smart UHPCs under compression showed a clear reduction in their electrical resistivity. However, under tension, their electrical resistivity measured from direct current (DC) measurement decreased, whereas that from alternating current (AC) measurement increased. This was because the electrical resistivity, from DC measurement, of smart UHPCs was primarily dependent on fiber crack bridging, whereas that from AC measurement was dependent on tunneling effects.

Point-of-care testing for the detection of SARS-CoV-2: a systematic review and meta-analysis

OBJECTIVE

To evaluate the diagnostic accuracy of the Food and Drug Administration Emergency Use Authorization (FDA-EUA) authorized point-of-care tests (POCTs) for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

MATERIALS AND METHODS

A systematic literature search was conducted using the PubMed, Embase, and Web of Science databases for articles published till August 10, 2020. We included studies providing information regarding diagnostic test accuracy of FDA-EUA POCTs for SARS-CoV-2 detection. The methodologic quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The review protocol is registered in the International Prospective Register of Systematic Reviews (protocol number CRD42020202248).

RESULTS

We included 26 studies describing a total of 3242 samples. The summary sensitivity and specificity were 0.94 [95% confidence interval (CI): 0.88-0.97] and 1.00 (95% CI: 0.99-1.00), respectively. The area under the summary receiver operating characteristic curve was 1.00 (95% CI: 0.99-1.00). A pooled analysis based on the index test revealed a summary sensitivity and specificity of Cepheid Xpert Xpress SARS-CoV-2 [0.99 (95% CI: 0.97-1.00) and 0.99 (95% CI: 0.94-1.00, respectively)] and ID NOW COVID-19 [0.78 (95% CI: 0.74-0.82) and 1.00 (95% CI: 0.98-1.00), respectively].

CONCLUSIONS

FDA-EUA POCTs, especially molecular assays, have high sensitivity, specificity, and overall diagnostic accuracy for detecting SARS-CoV-2. If approved, FDA-EUA POCTs can provide a rapid and practical way to identify infected individuals early on and help to limit the strain on the healthcare system. However, more high-quality clinical data are required to support our results.

Progress of x-ray imaging crystal spectrometer utilizing double crystal assembly on KSTAR

The x-ray imaging crystal spectrometer (XICS) for Korea Superconducting Tokamak Advanced Research (KSTAR) has been upgraded to increase its performance including measurement capabilities and stable operation. A dual crystal assembly for simultaneous measurements of the helium-like and hydrogen-like Ar spectra is successfully installed for improving measurement capabilities. Using a safety viewing port with an illuminator and removing the XICS control system from the harsh KSTAR tokamak hall for a stable operation are newly performed. The experimental results from the improved XICS are investigated.

Erratum: Correction of Affiliations in the Article "Clinical Characteristics and Treatment Outcomes in Children, Adolescents, and Young-adults with Hodgkin's Lymphoma: a KPHOG Lymphoma Working-party, Multicenter, Retrospective Study"

This corrects the article on p. e393 in vol. 35, PMID: 33258329.

Localization of Major Ephedra Alkaloids in Whole Aerial Parts of Ephedrae Herba Using Direct Analysis in Real Time-Time of Flight-Mass Spectrometry

Mass spectrometry-based molecular imaging has been utilized to map the spatial distribution of target metabolites in various matrixes. Among the diverse mass spectrometry techniques, matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) is the most popular for molecular imaging due to its powerful spatial resolution. This unparalleled high resolution, however, can paradoxically act as a bottleneck when the bio-imaging of large areas, such as a whole plant, is required. To address this issue and provide a more versatile tool for large scale bio-imaging, direct analysis in real-time-time of flight-mass spectrometry (DART-TOF-MS), an ambient ionization MS, was applied to whole plant bio-imaging of a medicinal plant, Ephedrae Herba. The whole aerial part of the plant was cut into 10–20 cm long pieces, and each part was further cut longitudinally to compare the contents of major ephedra alkaloids between the outer surface and inner part of the stem. Using optimized DART-TOF-MS conditions, molecular imaging of major ephedra alkaloids of the whole aerial part of a single plant was successfully achieved. The concentration of alkaloids analyzed in this study was found to be higher on the inner section than the outer surface of stems. Moreover, side branches, which are used in traditional medicine, represented a far higher concentration of alkaloids than the main stem. In terms of the spatial metabolic distribution, the contents of alkaloids gradually decreased towards the end of branch tips. In this study, a fast and simple macro-scale MS imaging of the whole plant was successfully developed using DART-TOF-MS. This application on the localization of secondary metabolites in whole plants can provide an area of new research using ambient ionization mass spectroscopy and an unprecedented macro-scale view of the biosynthesis and distribution of active components in medicinal plants.

Hemolytic uremic syndrome caused by sea anemone sting: a case report

Background

Some sea anemone toxins cause renal injuries resembling hemolytic uremic syndrome (HUS). To date, only a few cases of HUS caused by sea anemone stings have been reported. In this case report, we have described an HUS case caused by a sea anemone sting.

Case presentation

In November 2019, a 37-year-old man with no underlying disease was admitted to our hospital. He presented with intense pain, a rash on, and swelling in his right thigh. Two days prior, he had been stung by a sea anemone while scuba diving in Cebu, Philippines. His blood tests revealed renal dysfunction, and his platelet count was normal. However, on day three, the platelet count decreased rapidly. His blood haptoglobin level decreased, and schistocytes were identified on the peripheral blood smear. We suspected thrombotic microangiopathy and started the conventional treatment, comprising hemodialysis, blood transfusion, and antibiotic administration. ADAMTS-13 and genetic test results associated with atypical HUS were normal. Therefore, the patient was diagnosed with HUS caused by a sea anemone toxin.

Conclusions

HUS caused by a sea anemone toxin is rare, but it is a serious medical disease. Clinicians should consider HUS in patients with such clinical presentations, and they should make prompt treatment-related decisions.

The 2020 revision of the guidelines for the management of myeloproliferative neoplasms

In 2016, the World Health Organization revised the diagnostic criteria for myeloproliferative neoplasms (MPNs) based on the discovery of disease-driving genetic aberrations and extensive analysis of the clinical characteristics of patients with MPNs. Recent studies have suggested that additional somatic mutations have a clinical impact on the prognosis of patients harboring these genetic abnormalities. Treatment strategies have also advanced with the introduction of JAK inhibitors, one of which has been approved for the treatment of patients with myelofibrosis and those with hydroxyurea-resistant or intolerant polycythemia vera. Recently developed drugs aim to elicit hematologic responses, as well as symptomatic and molecular responses, and the response criteria were refined accordingly. Based on these changes, we have revised the guidelines and present the diagnosis, treatment, and risk stratification of MPNs encountered in Korea.

Clinical Characteristics and Viral RNA Detection in Children With Coronavirus Disease 2019 in the Republic of Korea

IMPORTANCE

There is limited information describing the full spectrum of coronavirus disease 2019 (COVID-19) and the duration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA detection in children.

OBJECTIVE

To analyze the full clinical course and the duration of SARS-CoV-2 RNA detectability in children confirmed with COVID-19 in the Republic of Korea, where rigorous public health interventions have been implemented.

DESIGN, SETTING, AND PARTICIPANTS

This case series of children with COVID-19 was conducted in 20 hospitals and 2 nonhospital isolation facilities across the country from February 18, 2020, to March 31, 2020. Children younger than 19 years who had COVID-19 were included.

EXPOSURES

Confirmed COVID-19, detected via SARS-CoV-2 RNA in a combined nasopharyngeal and oropharyngeal swab or sputum by real-time reverse transcription-polymerase chain reaction.

MAIN OUTCOMES AND MEASURES

Clinical manifestations during the observation period, including the time and duration of symptom occurrence. The duration of SARS-CoV-2 RNA detection was also analyzed.

RESULTS

A total of 91 children with COVID-19 were included (median [range] age, 11 [0-18] years; 53 boys [58%]). Twenty children (22%) were asymptomatic during the entire observation period. Among 71 symptomatic cases, 47 children (66%) had unrecognized symptoms before diagnosis, 18 (25%) developed symptoms after diagnosis, and only 6 (9%) were diagnosed at the time of symptom onset. Twenty-two children (24%) had lower respiratory tract infections. The mean (SD) duration of the presence of SARS-CoV-2 RNA in upper respiratory samples was 17.6 (6.7) days. Virus RNA was detected for a mean (SD) of 14.1 (7.7) days in asymptomatic individuals. There was no difference in the duration of virus RNA detection between children with upper respiratory tract infections and lower respiratory tract infections (mean [SD], 18.7 [5.8] days vs 19.9 [5.6] days; P = .54). Fourteen children (15%) were treated with lopinavir-ritonavir and/or hydroxychloroquine. All recovered, without any fatal cases.

CONCLUSIONS AND RELEVANCE

In this case series study, inapparent infections in children may have been associated with silent COVID-19 transmission in the community. Heightened surveillance using laboratory screening will allow detection in children with unrecognized SARS-CoV-2 infection.

COVID-19 in children across three Asian cosmopolitan regions

As another wave of COVID-19 outbreak has approached in July 2020, a larger scale COVID-19 pediatric Asian cohort summarizing the clinical observations is warranted. Children confirmed with COVID-19 infection from the Republic of Korea, the Hong Kong Special Administrative Region (HKSAR) and Wuhan, China, during their first waves of local outbreaks were included. Their clinical characteristics and the temporal sequences of the first waves of local paediatric outbreaks were compared. Four hundred and twenty three children with COVID-19 were analyzed. Wuhan had the earliest peak, followed by Korea and HKSAR. Compared with Korea and Wuhan, patients in HKSAR were significantly older (mean age: 12.9 vs. 10.8 vs. 6.6 years, p < 0.001, respectively) and had more imported cases (87.5% vs. 16.5% vs. 0%, p < 0.001, respectively). The imported cases were also older (13.4 vs. 7.6 years, p < 0.001). More cases in HKSAR were asymptomatic compared to Korea and Wuhan (45.5% vs. 22.0% vs. 20.9%, p < 0.001, respectively), and significantly more patients from Wuhan developed fever (40.6% vs. 29.7% vs. 21.6%, p=0.003, respectively). There were significantly less imported cases than domestic cases developing fever after adjusting for age and region of origin (p = 0.046). 5.4% to 10.8% of patients reported anosmia and ageusia. None developed pediatric multisystem inflammatory syndrome temporally associated with SARS-CoV-2 (PMIS-TS). In general, adolescents were more likely to be asymptomatic and less likely to develop fever, but required longer hospital stays. In conclusion, majority patients in this pediatric Asian cohort had a mild disease. None developed PIMS-TS. Their clinical characteristics were influenced by travel history and age.

Clinical Characteristics and Treatment Outcomes in Children, Adolescents, and Young-adults with Hodgkin's Lymphoma: a KPHOG Lymphoma Working-party, Multicenter, Retrospective Study

BACKGROUND

Hodgkin's lymphoma (HL) constitutes 10%-20% of all malignant lymphomas and has a high cure rate (5-year survival, around 90%). Recently, interest has increased concerning preventing secondary complications (secondary cancer, endocrine disorders) in long-term survivors. We aimed to study the epidemiologic features and therapeutic outcomes of HL in children, adolescents, and young adults in Korea.

METHODS

We performed a multicenter, retrospective study of 224 patients aged < 25 years diagnosed with HL at 22 participating institutes in Korea from January 2007 to August 2016.

RESULTS

A higher percentage of males was diagnosed at a younger age. Nodular sclerosis histopathological HL subtype was most common, followed by mixed cellularity subtype. Eighty-one (36.2%), 101 (45.1%), and 42 (18.8%) patients were classified into low, intermediate, and high-risk groups, respectively. Doxorubicin, bleomycin, vinblastine, dacarbazine was the most common protocol (n = 102, 45.5%). Event-free survival rate was 86.0% ± 2.4%, while five-year overall survival (OS) rate was 96.1% ± 1.4%: 98.7% ± 1.3%, 97.7% ± 1.6%, and 86.5% ± 5.6% in the low, intermediate, and high-risk groups, respectively (P = 0.021). Five-year OS was worse in patients with B-symptoms, stage IV disease, high-risk, splenic involvement, extra-nodal lymphoma, and elevated lactate dehydrogenase level. In multivariate analysis, B-symptoms and extra-nodal involvement were prognostic factors for poor OS. Late complications of endocrine disorders and secondary malignancy were observed in 17 and 6 patients, respectively.

CONCLUSION

This is the first study on the epidemiology and treatment outcomes of HL in children, adolescents, and young adults in Korea. Future prospective studies are indicated to develop therapies that minimize treatment toxicity while maximizing cure rates in children, adolescents, and young adults with HL.

Supramolecular Porphyrin Nanostructures Based on Coordination-Driven Self-Assembly and Their Visible Light Catalytic Degradation of Methylene Blue Dye

A series of porphyrin triads (1–4), in which each triad is composed of a Sn(IV) porphyrin and two free-base (or Zn(II)) porphyrins, was synthesized and their self-assembled nanostructures were studied. Depending on the substituent on porphyrin moieties, each triad was self-assembled into a different nanostructure. In particular, the cooperative coordination of 3-pyridyl groups in the Sn(IV) porphyrin with the axial Zn(II) porphyrins in triad 4 leads to forming uniform nanofibers with an average width of 10–22 nm. Other triads without the coordinating interaction between the central Sn(IV) porphyrin and the axial porphyrins formed irregularly shaped aggregates in contrast. The morphologies of nanofiber changed drastically upon the addition of pyrrolidine, in which pyrrolidine molecules break down the self-assembly process by coordinating with the axial Zn(II) porphyrins. All porphyrin aggregates exhibited efficient photocatalytic performances on the degradation of methylene blue dye under visible light irradiation. The degradation efficiencies after 2 h were observed to be between 70% and 95% for the aggregates derived from the four triads.

Phase 2 study of afatinib among patients with recurrent and/or metastatic esophageal squamous cell carcinoma

BACKGROUND

The objective of the current study was to investigate the clinical activity of, safety of, and predictive biomarkers for afatinib, an irreversible pan-ErbB kinase inhibitor, in patients with recurrent and/or metastatic esophageal squamous cell carcinoma (R/M-ESCC).

METHODS

Patients with R/M-ESCC that was refractory to platinum-based chemotherapy were enrolled in the current multicenter, single-arm, phase 2 study and received afatinib at a dose of 40 mg/day. The primary endpoint was the objective response rate. Secondary endpoints included progression-free survival, overall survival, the disease control rate, and the safety profile. To identify predictive biomarkers, single-nucleotide variations, short insertions/deletions, and somatic copy number alterations were assessed using whole-exome sequencing and their associations with clinical outcomes were analyzed.

RESULTS

Among 49 enrolled patients, the objective response rate and disease control rate were 14.3% and 73.3%, respectively. With a median follow-up of 6.6 months, the median progression-free survival and overall survival were 3.4 months and 6.3 months, respectively. Treatment-related adverse events were noted to have occurred in 33 patients (67.3%), with the majority being of grade 1 to 2 (adverse events were graded and recorded based on the National Cancer Institute Common Terminology Criteria for Adverse Events [version 4.03]). Whole-exome sequencing demonstrated that the ESCC genomes of patients who demonstrated a response to afatinib were enriched with genomic alterations of TP53 and epidermal growth factor receptor (EGFR). As a predictive marker, a score derived from TP53 disruptive mutations and EGFR amplifications and/or missense mutations demonstrated a significant association with the response to afatinib. The score based on the mutational status of EGFR and TP53 achieved a performance of an area under the curve of 0.86 in predicting the sensitivity of afatinib.

CONCLUSIONS

The results of the current study demonstrated that afatinib can confer modest clinical benefits with manageable toxicity in patients with platinum-resistant R/M-ESCC. Identification of TP53 alterations and EGFR amplifications may serve as predictive markers with which to identify patients with R/M-ESCC who may benefit from afatinib.

LAY SUMMARY

Esophageal squamous cell carcinoma (ESCC) is a type of cancer with a dismal prognosis and very limited treatment options. The clinical efficacy of afatinib was evaluated in patients with recurrent and/or metastatic ESCC, with adverse events demonstrating the modest efficacy with manageable toxicity of this irreversible, pan-ErbB kinase inhibitor. Whole-exome sequencing analysis of 41 cases of ESCC further revealed that the patients harboring epidermal growth factor receptor (EGFR) amplifications and disruptive TP53 mutations are more likely to benefit from treatment with afatinib. The results of the current study have highlighted the clinical value of EGFR and TP53 as predictive biomarkers of platinum-resistant recurrent and/or metastatic ESCC for afatinib sensitivity.

Clinical impact of frailty on treatment outcomes of elderly patients with relapsed and/or refractory multiple myeloma treated with lenalidomide plus dexamethasone

We compared efficacy and safety, according to frailty, of elderly patients with relapsed and refractory multiple myeloma (RRMM) treated with lenalidomide and dexamethasone (Rd), for whom bortezomib treatment had failed. Patients, 164 (52.9%) and 146 (47.1%), were classified as non-frail and frail using a simplified frailty scale. The overall response rates (ORR) and survival outcomes were lower in frail than in non-frail patients (ORR: 56.2% vs. 67.7%, P = 0.069; median progression free survival: 13.17 vs. 17.80 months, P = 0.033; median overall survival: 23.00 vs. 36.27 months, P = 0.002, respectively). The number of treatment emergent adverse events in grade 3 or worse was higher in frail than in non-frail patients (41.8% vs. 24.4%, P = 0.002, respectively). In frail patients, independent poor prognostic factors for survival were two or more Charlson comorbidity index (CCI) score, prior to exposure to both bortezomib and thalidomide, and achieved less than partial response In conclusion, frailty could predict clinical outcomes of Rd treatment in elderly patients with RRMM who had failed prior bortezomib. In frail patients, lower CCI in addition to less previous treatment exposure and deep response were associated with better survival.

Treatment strategy and outcomes in locally advanced head and neck squamous cell carcinoma: a nationwide retrospective cohort study (KCSG HN13-01)

Background

By investigating treatment patterns and outcomes in locally advanced head and neck squamous cell carcinoma (LA-HNSCC), we aimed at providing valuable insights into the optimal therapeutic strategy for physicians in real-world practice.

Methods

This is a multi-institutional study enrolled the patients with stage III to IVB LA-HNSCC, except for nasopharyngeal carcinoma, from 2004 to 2015 in thirteen referral hospitals capable of multidisciplinary care.

Results

A total of 445 LA-HNSCC patients were analyzed. The median age was 61 years (range, 24–89). The primary tumor location was the oropharynx in 191 (43%), oral cavity in 106 (24%), hypopharynx in 64 (14%), larynx in 57 (13%) and other sites in 27 (6%). The most common stage was T2 in 172 (39%), and N2 in 245 (55%). Based on treatment intents, 229 (52%) of the patients received definitive concurrent chemoradiotherapy (CCRT) and 187 (42%) underwent surgery. Approximately 158 (36%) of the study population received induction chemotherapy (IC). Taken together, 385 (87%) of the patients underwent combined therapeutic modalities. The regimen for definitive CCRT was weekly cisplatin in 58%, 3-weekly cisplatin in 28% and cetuximab in 3%. The preferred regimen for IC was docetaxel with cisplatin in 49%, and docetaxel, cisplatin plus fluorouracil in 27%. With a median follow-up of 39 months, one-year and two-year survival rates were 89 and 80%, respectively. Overall survival was not significantly different between CCRT and surgery group (p = 0.620).

Conclusions

In patients with LA-HNSCC, the majority of patients received combined therapeutic modalities. Definitive CCRT, IC then definitive CCRT, and surgery followed by adjuvant CCRT or radiotherapy are the preferred multidisciplinary strategies in real-world practice.

Randomized phase II study of axitinib versus observation in patients with recurred or metastatic adenoid cystic carcinoma

6503

Background: Adenoid cystic carcinoma (ACC) does not respond to cytotoxic chemotherapy. Several anti-angiogenic agents were evaluated in single arm phase II trials. However, the role of chemotherapy is still controversial, because of natural stable disease course without chemotherapy and lack of randomized trial. We firstly conducted a randomized trial to evaluate the efficacy of axitinib compared to observation. Methods: In this multicenter, prospective phase II trial, we enrolled recurred, metastatic ACC patients who progressed within 9 months. Patients were randomly assigned either axitinib (5mg twice daily) or observation arm with 1:1 ratio. Crossover to the axitinib arm was permitted for patients in the observation arm who had disease progression. The primary endpoint was 6-month progression-free survival (PFS) rate. The secondary endpoints included objective response rate (ORR), overall survival (OS), PFS, duration of response and adverse events. Results: A total of 60 patients randomly allocated to axitinib (N=30) and observation arm (N=30) and response evaluation was conducted in 57 patients. With a median follow-up of 25.4 months, the 6-month PFS rate was 73.2% (95% confidence interval [CI], 54.8 to 88.1%) in the axitinib arm and 23.2% (95% CI, 9.3 to 41.1%) in the observation arm (hazard ratio, 0.19; 95% CI, 0.08 to 0.45; P < 0.001). Median PFS was 10.8 months in axitinib arm and 2.8 months in observation arm ( P < 0.001). The ORR was 3.3% (95% CI, 0.1 to 17.2%) in the axitinib arm, and 0% (95% CI, 0 to 12.8%) in the observation arm. The disease control rate was 100% (95% CI, 88.4 to 100%) in the axitinib arm and 51.9% (95% CI, 32.0 to 71.3%) in the observation arm. After crossover, ORR of axitinib in the observation arm was 11.1% (95% CI, 2.4 to 29.2%). Median OS was not reached in axitinib arm, 28.5 months in observation arm ( P = 0.688). The most frequently reported adverse events of axitinib were grade 1 or 2 oral mucositis and fatigue. Detailed data of adverse events and mutational profile data will be presented. Conclusions: In this first randomized trial in patients with recurred or metastatic ACC, axitinib significantly increased 6-month PFS rate compared to observation. Clinical trial information: NCT02859012 .

A phase II study of ibrutinib in combination with rituximab-cyclophosphamide-doxorubicin hydrochloride-vincristine sulfate-prednisone therapy in Epstein-Barr virus-positive, diffuse large B cell lymphoma (54179060LYM2003: IVORY study): results of the final analysis

Epstein-Barr virus (EBV) positivity in diffuse large B cell lymphoma (DLBCL) provokes a critical oncogenic mechanism to activate intracellular signaling by LMP1. LMP1 specifically mimics the role of BTK-dependent B cell receptor. Therefore, a trial considering RCHOP therapy along with ibrutinib (I-RCHOP) in combination was conducted among patients with EBV-positive DLBCL. This study was an open-label, single-arm, prospective multicenter phase II clinical trial. Patients received 560 mg of ibrutinib with RCHOP every 3 weeks until 6 cycles were completed or progression or unacceptable toxicity was observed. The primary endpoint was objective response, while secondary endpoints included toxicity, progression-free survival, and overall survival. A matched case-control analysis was completed to compare the efficacy and toxicity of I-RCHOP and RCHOP, respectively, in EBV-positive DLBCL patients. From September 2016 to August 2019, 24 patients proven to have EBV-positive DLBCL in the tissue were enrolled and received I-RCHOP. Their median age was 58 years (range, 28-84 years). The objective overall response was 66.7%, including 16 patients who achieved complete response after 6 cycles. Patients aged younger than 65 years presented a superior OR (87.5%) as compared with those older than 65 years (25.0%; p = 0.01). In a matched case-control study, I-RCHOP therapy provoked a more favorable complete response rate (87.3%) than did RCHOP (68.8%) in those younger than 65 years. Treatment-related mortality was linked most frequently with I-RCHOP therapy (four patients presented with unusual infection without Gr3/4 neutropenia) in the older age group (age ≥ 65 years). In conclusion, in this phase II trial for EBV-positive DLBCL, I-RCHOP was effective but did not show a significant improvement in response and survival in comparison with RCHOP. Also, I-RCHOP promoted serious toxicity and treatment-related death in older patients.

Pomalidomide, cyclophosphamide, and dexamethasone for elderly patients with relapsed and refractory multiple myeloma: A study of the Korean Multiple Myeloma Working Party (KMMWP-164 study)

Patients with transplant‐ineligible relapsed and refractory multiple myeloma (RRMM) have a short life expectancy, especially when they have failed both the proteasome inhibitor and immunomodulator therapies. This study aimed to assess the efficacy and safety of pomalidomide, cyclophosphamide, and dexamethasone (PCd) in elderly patients with RRMM. This phase 2 clinical trial recruited 55 elderly patients with RRMM. The patients underwent a 28‐day treatment cycle: pomalidomide (4 mg/day on days 1‐21, administered orally) and cyclophosphamide (400 mg/day on days 1, 8, and 15; administered orally) plus dexamethasone. The median (range) age of the patients was 73.3 (64‐86) years, and 8 (14.5%) patients who were ≥ 80 years old. Eight (14.5%) and 31 (56.4%) patients exhibited stage III (revised international staging system) and frail status (simplified frailty scale), respectively. The overall response rate (ORR) and clinical benefit rate (CBR) of PCd therapy were 58.2% and 72.7%, respectively. The median PFS and median overall survival (OS) were 6.90 months (95% CI, 4.7‐9.0) and 18.48 months (95% CI, 9.4‐27.6), respectively. The incidence rate of grade ≥ 3 non‐hematological toxicities was 70.8%. In particular, the incidence rate of primary infection was 45.4%, including 21.8% for pneumonia, 9.0% for sepsis, and 14.6% for febrile neutropenia. In conclusion, PCd is an effective regimen for elderly patients with RRMM who had failed both bortezomib and lenalidomide treatments, but in whom the treatment‐associated infection is the main cause of morbidity and mortality.

P1274 Early surgery versus watchful waiting in patients with moderate aortic stenosis and left ventricular systolic dysfunction

Background

Aortic stenosis (AS) induces significant pressure overload to the left ventricle (LV) and its burden may increase if there is concomitant LV systolic dysfunction. Severe AS with LV systolic dysfunction is a class I indication for aortic valve replacement (AVR) irrespective of symptoms, however, this recommendation is not well established in those with moderate AS and LV systolic dysfunction. In this study, we sought to investigate the clinical impact of surgical AVR among patients with moderate AS and LV systolic dysfunction.

Methods

From 2001 to 2017, we retrospectively but consecutively identified patients with moderate AS and LV systolic dysfunction from a single tertiary hospital. Moderate AS was defined as aortic valve area between 1.0 and 1.5cm2 and LV systolic dysfunction as LV ejection fraction less than 50%. The primary outcome was all-cause death and we additionally analyzed cardiac death as a secondary endpoint. The outcomes were compared between those who underwent early surgical AVR at the stage of moderate AS versus those who were followed without AVR at the outpatient clinic.

Results

Among a total of 257 patients with moderate AS and concomitant LV systolic dysfunction (70.0 ± 11.3 years, 63.4% of male), 34 patients received early AVR. Patients in the AVR group was younger than the observation group (64.2 ± 8.1 vs. 70.9 ± 11.5, respectively), and had a lower prevalence of hypertension and chronic kidney disease. During a mean of 3-year follow up, 112 patients (47.5%) died and the overall death rate was 15.367 per 100 person-year (PY). The AVR group showed a significantly lower rate of all-cause death than the observation group (5.241PY vs. 18.160PY, p-value = 0.002). After multivariable Cox proportional hazard regression adjusting for age, sex, comorbidities and laboratory data, early AVR at the stage of moderate AS significantly reduced the risk of all-cause death (hazard ratio [HR] 0.340, 95% confidence interval [CI] 0.117 - 0.985, p-value = 0.047). However, there was no risk reduction of cardiac death (HR 0.578 95% CI 0.150 - 2.231, p-value = 0.426).

Conclusions

In patients with moderate AS and LV systolic dysfunction, AVR reduces the risk of all-cause death. A prospective design study is warranted to confirm our findings in the near future.

Abstract P1274 Figure. Kaplan-Meier curves for deaths

Comparative Performance of Four Electrodes for Measuring the Electromechanical Response of Self-Damage Detecting Concrete under Tensile Load

Self-damage or/and stress-sensing concrete is a promising area of research for measuring the electromechanical response of structural materials using more robust sensors. However, the copper and silver paste sensors widely used in such applications can be expensive and have detrimental effects on the load carrying capacity and durability of the structural systems upon which they are installed. Accordingly, this study compared the performance of four electrode types-conventional copper tape with silver paste (CS), copper film with type 1 carbon tape (CC1), copper film with type 2 carbon tape (CC2), and copper wire and film with type 2 carbon tape (WC2)-to develop an economical and practical electrode for measuring the electromechanical response of self-damage-detecting concrete. The CC1 electrode exhibited comparable performance to the CS electrode in measuring the electromechanical response of self-damage-detecting concrete, despite requiring a longer polarization time (80 s) than the CS electrode (25 s). The CS electrode exhibited a higher damage-sensing capacity (GF₂), whereas the CC1 electrode exhibited a higher strain-sensing capacity (GF₁), as well as good damage-sensing capacity. Therefore, the CC1 electrode using copper film with type 1 carbon tape was determined to be the best alternative to the conventional CS electrode.

Effect of Stem Cell Source and Dose on Allogeneic Hematopoietic Stem Cell Transplantation in Adult Patients with Idiopathic Aplastic Anemia: Data from the Korean Aplastic Anemia Trials

OBJECTIVE

We aimed to evaluate the effect of stem cell source and dose on the survival of various donor subgroups, such as matched sibling donor (MSDs) and alternative donors (ADs), upon bone marrow (BM) or peripheral blood stem cell (PBSC) infusion in aplastic anemia (AA).

METHODS

We retrospectively investigated the effects of stem cell source and dose on allogeneic hematopoietic stem cell transplantation (alloHSCT) in AA.

RESULTS

A total of 267 patients were included in this analysis. The BM-treated group showed an association with low incidence of any-grade acute graft versus host disease (GvHD) (p < 0.001). A higher stem cell dose was related with a low incidence of extensive chronic GvHD in MSDs (p = 0.025). Multivariate analysis for overall survival (OS) revealed that only age at alloHSCT <31 years (p = 0.010) and prior platelet transfusion <86 U (p = 0.046) in MSDs and higher stem cell dose (hazard ratio = 2.596, p = 0.045) in ADs were favorable prognostic factors.

CONCLUSION

PBSCs could be preferred in AD because high stem cell dose may be easily achieved to improve the OS at the expense of acute GvHD. However, BM stem cells are preferred in MSDs.

Effect of Stellate Ganglion Block on the Regional Hemodynamics of the Upper Extremity: A Randomized Controlled Trial

BACKGROUND

The success of stellate ganglion block (SGB) is traditionally determined on the basis of findings such as Horner's syndrome, temperature rise in the face, hyperemia of the tympanic membrane, and nasal congestion. However, decreases in vascular resistance and increases in blood flow in the arm may be more meaningful findings. To date, the effect of SGB on the regional hemodynamics of the arm has not been evaluated using pulsed-wave Doppler ultrasound.

METHODS

A total of 52 patients who were to undergo orthopedic surgery of the forearm were randomly assigned to either the mepivacaine group (SGB with 5 mL of 0.5% mepivacaine) or the saline group (SGB with 5 mL of normal saline). Before surgery, a single anesthesiologist performed a SGB under ultrasound guidance. The temperature of the upper extremity and the resistance index and blood flow in the brachial artery were measured before SGB, 15 and 30 minutes after SGB, and 1 hour after surgery. The severity of pain, requirement for rescue analgesics, and side effects of the local anesthetic agent were all documented.

RESULTS

After SGB, the resistance index decreased significantly and the blood flow increased significantly in the brachial artery of members of the mepivacaine group (15 minutes: P = .004 and P < .001, respectively; 30 minutes: P < .001 and P < .001, respectively). However, these values normalized after surgery. The severity of pain, need for rescue analgesics, and incidence of adverse effects were not significantly different between the 2 groups.

CONCLUSIONS

Although SGB did not decrease the pain associated with forearm surgery, ultrasound-guided SGB did increase blood flow and decrease vascular resistance in the arm. Therefore, pulsed-wave Doppler may be used to monitor the success of SGB.

Effects of a Short Heat Treatment Period on the Pullout Resistance of Shape Memory Alloy Fibers in Mortar

The feasibility of the crack closure of cementitious composites reinforced with shape memory alloy (SMA) fibers was investigated by performing single-fiber pullout tests. To demonstrate the fast crack closing ability, in this study, a heat treatment (300 °C) was applied for a short time (10 min). A short heat treatment was applied for 10 min, after the slip reached 0.5 mm, to activate the shape memory effects of cold-drawn SMA fibers. Two types of alloys were investigated, NiTi and NiTiNb, with two geometries, either smooth or dog-bone-shaped. During the heat treatment, the pullout stress of the SMA fibers initially decreased due to thermal extension, and then increased after heating for 1–3 min, resulting from the shape memory effects. However, their pullout stress recovery during and after the heat treatment was different for the different alloys and fiber geometries. The NiTi fibers generally produced a higher and faster recovery in terms of their pullout stress than the NiTiNb fibers, while the dog-bone-shaped fibers showed a faster pullout stress recovery than the smooth fibers.

Photoinduced electron transfer upon supramolecular complexation of (porphyrinato)Sn-viologen with cucurbit[7]uril

The synthesis of (porphyrinato)Sn-viologen, 1, and its supramolecular complexation with cucurbit[7]uril (CB[7]) were studied. ¹H NMR spectroscopic studies obviously reveal that 1 forms a 1 : 2 supramolecular complex with CB[7] through the inclusion of viologen moieties of 1 into the cavity of CB[7]. The cyclic voltammetric study supports that the binding affinity of the radical cation forms is comparable to that of the di-cation viologen toward CB[7]. The fluorescence arising from the porphyrin moiety is significantly quenched upon the complexation of 1 with CB[7]. The ps-time-resolved fluorescence and ns-transient absorption spectroscopic studies reveal that the photoinduced electron transfer (PET) between viologen and Sn(iv) porphyrin of 1 takes place from the first excited singlet (S₁) state and the second excited triplet (T₂) state of the porphyrin moiety upon complexation with CB[7], while the PET from the S₁ state is negligible in the absence of CB[7].