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1.
Cancer Immunol Immunother ; 72(5): 1233-1246, 2023 May.
Article in English | MEDLINE | ID: mdl-36385211

ABSTRACT

The development of new treatment agents in recent decades has significantly improved the survival of patients with multiple myeloma (MM). Nonetheless, MM remains an incurable disease; therefore, novel combination therapies are required. Natural killer (NK) cells are one of the safest immunotherapeutic options. In this study, we found that the anti-myeloma activity of expanded NK cells (eNKs) was improved by daratumumab, lenalidomide, and dexamethasone (DRd) in an MM xenograft mouse model. NK cells expanded from peripheral blood mononuclear cells collected from MM patients were highly cytotoxic against DRd pretreated tumor cells in vitro. To mimic the clinical protocol, a human MM xenograft model was developed using human RPMI8226-RFP-FLuc cells in NOD/SCID IL-2Rγnull (NSG) mice. MM bearing mice were randomly divided into six groups: no treatment, eNK, Rd, Rd + eNKs, DRd, and DRd + eNKs. DRd significantly enhanced the cytotoxicity of eNKs by upregulating NK cell activation ligands and effector function. DRd in combination with eNKs significantly reduced the serum M-protein level and prolonged mouse survival. In addition, DRd significantly increased the persistence of eNK and homing to MM sites. These results show that the anti-myeloma activity of ex vivo-expanded and activated NK cells is augmented by the immunomodulatory effect of DRd in MM-bearing mice, suggesting the therapeutic potential of this combination for MM patients.


Subject(s)
Multiple Myeloma , Humans , Animals , Mice , Multiple Myeloma/therapy , Lenalidomide/pharmacology , Heterografts , Leukocytes, Mononuclear , Mice, SCID , Mice, Inbred NOD , Killer Cells, Natural , Dexamethasone/pharmacology
2.
Reproduction ; 165(1): 135-146, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36322471

ABSTRACT

In brief: Mealtime changes in pregnant mice revealed impaired neurobehavioral development in mouse offspring. This study is the basis for investigating diseases associated with neurobehavioral development of adult offspring of pregnant shift-working women. Abstract: Most organisms on Earth have a biological clock, and their physiological processes are regulated by a 1-day cycle. In modern society, several factors can disturb these biological clocks in humans; in particular, individuals working in shifts are exposed to stark environmental changes that interfere with their biological clock. They have a high risk of various diseases. However, there are scarce experimental approaches to address the reproductive and health consequences of shift work in the offspring of exposed individuals. In this study, considering the fact that shift workers usually have their meals during their adjusted working time, we aimed to examine the effects of a 12-h shift with usual mealtime as a plausible night work model on the neurobehavioral development of adult mouse offspring. In these offspring, early exposure to this mealtime shift differentially affected circadian rhythmic variables and total locomotor activity depending on the timing and duration of restrictive feeding. Moreover, neurobehavioral alterations such as declined short-term memory and depressive-like behavior were observed in adulthood. These results have implications for the health concerns of shift-working women and their children.


Subject(s)
Adult Children , Circadian Rhythm , Humans , Pregnancy , Adult , Child , Animals , Female , Mice , Circadian Rhythm/physiology , Weaning , Behavior, Animal , Reproduction
3.
Ann Hematol ; 102(8): 2233-2240, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37392367

ABSTRACT

Despite the development of effective agents for multiple myeloma (MM), the management of patients with high-risk MM (HRMM) is challenging. High-dose treatment followed by autologous stem cell transplantation (ASCT) is regarded as upfront treatment for transplant-eligible patients with HRMM. In the present study, we retrospectively investigated the efficacies of two conditioning regimens for upfront ASCT in newly diagnosed patients with MM and high-risk features: high-dose melphalan (HDMEL; 200 mg/m2) and busulfan plus melphalan (BUMEL). In total, 221 patients underwent ASCT between May 2005 and June 2021; among these 221 patients, 79 had high-risk cytogenetic abnormalities. In patients with high-risk cytogenetics, BUMEL showed a tendency toward longer overall survival (OS) and progression-free survival (PFS) compared to HDMEL (median OS; not reached vs. 53.2 months; P = 0.091, median PFS; not reached vs. 31.7 months; P = 0.062). Additionally, multivariate analysis revealed that BUMEL was significantly associated with PFS (hazard ratio = 0.37, 95% confidence interval = 0.15-0.89, P = 0.026). We compared BUMEL with HDMEL in patients with other high-risk features, such as high lactate dehydrogenase level, extramedullary disease, and poor response to frontline therapy. Notably, among patients with less than very good partial response (VGPR) to frontline therapy, median PFS was significantly longer in the BUMEL group than in the HDMEL group (55.1 vs. 17.3 months, respectively; P = 0.011). These findings indicate that BUMEL may be an effective conditioning regimen for upfront ASCT in MM patients with high-risk cytogenetics; BUMEL may be more appropriate than HDMEL for patients with less than VGPR to frontline therapy.


Subject(s)
Hematopoietic Stem Cell Transplantation , Multiple Myeloma , Humans , Melphalan , Multiple Myeloma/drug therapy , Busulfan , Retrospective Studies , Transplantation, Autologous , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Transplantation Conditioning , Stem Cell Transplantation
4.
Reproduction ; 163(5): 323-331, 2022 04 05.
Article in English | MEDLINE | ID: mdl-35286277

ABSTRACT

The physiological processes of organisms in this rotating planet can adjust according to the time of day via built-in circadian clocks. However, more people are having different shift works, which can increase the risk of pathological conditions including altered reproductive function. Thus, circadian rhythm disturbance has become prevalent in the modern society. Specifically, epidemiological evidence has shown that shift-working women are at high risk of spontaneous abortions, irregular menstrual cycles, and low-birth-weight babies. The current study aimed to investigate the effects of circadian rhythm disturbances on the reproductive function of mice caused by dietary time shift, which is common among night-shift workers. According to the schedule of restricted feeding, the mice were classified into the free feeding, daytime feeding, and night feeding groups. The fertility indices of each group were then evaluated. Activity monitoring was performed to determine whether pregnancy delay might be attributed to mealtime shift. Moreover, the estrous cycle of female mice and the reproductive phenotype of male mice were investigated. Results showed that a 12-h mealtime shift significantly delayed successful conception, which could be attributed to a disrupted estrous cycle, in adult female mice.


Subject(s)
Circadian Rhythm , Work Schedule Tolerance , Animals , Female , Humans , Male , Meals , Menstruation Disturbances , Mice , Pregnancy , Reproduction
5.
BMC Infect Dis ; 22(1): 112, 2022 Feb 01.
Article in English | MEDLINE | ID: mdl-35105335

ABSTRACT

BACKGROUND: Inappropriate use of antibiotics not only increases antibiotic resistance as collateral damage but also increases clinical failure rates and medical costs. The purpose of this study was to determine the relationship between the appropriateness of antibiotic prescription and outcomes of community-acquired acute pyelonephritis (CA-APN). METHODS: A multicenter prospective cohort study was conducted at eight hospitals in Korea between September 2017 and August 2018. All hospitalized patients aged ≥ 19 years who were diagnosed with CA-APN on admission were recruited. The appropriateness of empirical and definitive antibiotics, as well as the appropriateness of antibiotic treatment duration and route of administration, was evaluated in accordance with the guideline and expert opinions. Clinical outcomes and medical costs were compared between patients who were administered antibiotics 'appropriately' and 'inappropriately.' RESULTS: A total of 397 and 318 patients were eligible for the analysis of the appropriateness of empirical and definitive antibiotics, respectively. Of them, 10 (2.5%) and 18 (5.7%) were administered 'inappropriately' empirical and definitive antibiotics, respectively. Of the 119 patients whose use of both empirical and definitive antibiotics was classified as 'optimal,' 57 (47.9%) received antibiotics over a longer duration than that recommended; 67 (56.3%) did not change to oral antibiotics on day 7 of hospitalization, even after stabilization of the clinical symptoms. Patients who were administered empirical antibiotics 'appropriately' had shorter hospitalization days (8 vs. 10 days, P = 0.001) and lower medical costs (2381.9 vs. 3235.9 USD, P = 0.002) than those who were administered them 'inappropriately.' Similar findings were observed for patients administered both empirical and definitive antibiotics 'appropriately' and those administered either empirical or definitive antibiotics 'inappropriately'. CONCLUSIONS: Appropriate use of antibiotics leads to better outcomes, including reduced hospitalization duration and medical costs.


Subject(s)
Pyelonephritis , Anti-Bacterial Agents/therapeutic use , Drug Resistance, Microbial , Hospitalization , Humans , Prospective Studies , Pyelonephritis/drug therapy
6.
J Korean Med Sci ; 37(1): e2, 2022 Jan 03.
Article in English | MEDLINE | ID: mdl-34981678

ABSTRACT

BACKGROUND: In diffuse large B-cell lymphoma (DLBCL), bone marrow involvement (BMI) has an important clinical implication as a component of staging and International Prognostic Index. This study aimed to determine whether molecular analysis of immunoglobulin heavy chain (IgH) genes and positron emission tomography-computed tomography (PET/CT) could overcome the limitation of defining morphologic BMI by trephination biopsy and could increase the diagnostic accuracy or prognostic prediction. METHODS: A total of 94 de novo patients with DLBCL underwent PET/CT, polymerase chain reaction (PCR) test for detection of IgH gene rearrangement, and unilateral bone marrow (BM) trephination at diagnosis. RESULTS: A total of 9 patients (9.6%) were confirmed to present morphologic BMI (mBMI) based on trephination biopsy. On the other hand, 21 patients (22.3%) were confirmed to have IgH clonality (IgH BMI), while 16 (17.0%) were classified with BMI based on the assessment of PET/CT (PET BMI). Each IgH rearrangement PCR and PET/CT showed the high negative predictive value of detecting the BMI. However, the combined assessment of IgH rearrangement and PET/CT could increase the diagnostic accuracy and specificity with 87.2% and 97.0%, respectively. The survival outcome of patients with double positive PET BMI and IgH BMI was significantly worse than that with either single positive PET BMI or IgH BMI, and even less than patients with neither PET BMI nor IgH BMI (3-year PFS: 50.0% vs. 75.4% vs. 97.9%, P = 0.007, 3-year OS: 50.0% vs. 75.6% vs. 80.1%, P = 0.035, respectively). CONCLUSION: This study suggests that the combined evaluation of PET/CT and IgH rearrangement could give additional information for predicting therapeutic outcomes in patients with negative morphologic BMI as an important part of the prognosis.


Subject(s)
Bone Marrow Neoplasms/diagnostic imaging , Fluorodeoxyglucose F18 , Lymphoma, Large B-Cell, Diffuse/diagnostic imaging , Positron Emission Tomography Computed Tomography/methods , Radiopharmaceuticals , Adult , Aged , Aged, 80 and over , Biopsy/methods , Bone Marrow Examination , Bone Marrow Neoplasms/genetics , Bone Marrow Neoplasms/immunology , Bone Marrow Neoplasms/pathology , Female , Gene Rearrangement, B-Lymphocyte, Light Chain , Humans , Immunoglobulin Heavy Chains , Lymphoma, Large B-Cell, Diffuse/genetics , Lymphoma, Large B-Cell, Diffuse/immunology , Lymphoma, Large B-Cell, Diffuse/pathology , Male , Middle Aged , Prognosis , Prospective Studies , Young Adult
7.
J Infect Chemother ; 27(7): 1013-1019, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33642250

ABSTRACT

BACKGROUND: Community-acquired acute pyelonephritis (CA-APN) is relatively rare in men. This study aimed to compare the clinical characteristics of CA-APN between male and female patients. METHODS: We prospectively collected the clinical and microbiological data of hospitalized CA-APN patients aged ≥19 years in South Korea from March 2010 to February 2011 in 11 hospitals and from September 2017 to August 2018 in 8 hospitals. Only the first episodes of APN of each patient during the study period were included. RESULTS: From 2010 to 2011, 573 patients from 11 hospitals were recruited, and from 2017 to 2018, 340 patients were recruited from 8 hospitals. Among them, 5.9% (54/913) were male. Male patients were older (66.0 ± 15.2 vs. 55.3 ± 19.0 years, P < 0.001), had a higher Charlson comorbidity index (1.3 ± 1.5 vs. 0.7 ± 1.2, P = 0.027), and had a higher proportion of structural problems in the urinary tract (40.7% vs. 6.1%, P < 0.001) than female patients. Moreover, the total duration of antibiotic treatment was longer (21.8 ± 17.8 d vs. 17.3 ± 9.4 d, P = 0.001) and the proportion of carbapenem usage was higher (24.1% vs. 9.5%, P = 0.001) in men than in women. Male patients were hospitalized for longer durations than female patients (median, 10 d vs. 7 d, P < 0.001). CONCLUSIONS: Male CA-APN patients were older and had more comorbidities than female CA-APN patients. In addition, male patients received antibiotic treatment for a longer duration than female patients.


Subject(s)
Community-Acquired Infections , Pyelonephritis , Acute Disease , Community-Acquired Infections/drug therapy , Community-Acquired Infections/epidemiology , Female , Humans , Male , Pyelonephritis/drug therapy , Pyelonephritis/epidemiology , Republic of Korea/epidemiology , Retrospective Studies , Risk Factors
8.
J Korean Med Sci ; 36(24): e179, 2021 Jun 21.
Article in English | MEDLINE | ID: mdl-34155840

ABSTRACT

BACKGROUND: South Korea has been experiencing a third wave of coronavirus disease 2019 (COVID-19) since mid-November 2020. Our hospital in Gwangju metropolitan city experienced a healthcare-associated COVID-19 outbreak early in the third wave. The first confirmed COVID-19 patient was a symptomatic neurosurgery resident with high mobility throughout the hospital. We analyzed the transmission routes of nosocomial COVID-19 and discussed infection control strategies. METHODS: We retrospectively analyzed the severe acute respiratory syndrome coronavirus 2 reverse transcription-polymerase chain reaction (RT-PCR) testing results according to time point and evaluated transmission routes. RESULTS: Since COVID-19 was first confirmed in a healthcare worker (HCW) on 11/13/2020, we performed RT-PCR tests for all patients and caregivers and four complete enumeration surveys for all HCWs. We detected three clusters of nosocomial spread and several sporadic cases. The first cluster originated from the community outbreak spot, where an asymptomatic HCW visited, which led to a total of 22 cases. The second cluster, which included patient-to-patient transmission, originated from a COVID-19 positive caregiver before diagnosis and the third cluster involved a radiologist and a banker. We took measures to isolate Building 1 of the hospital for 17 days and controlled the outbreak during a period of increasing community COVID-19 prevalence. Universal screening of all inpatients upon admission and resident caregivers was made mandatory and hospital-related employees are now screened monthly. CONCLUSION: Infection control strategies to prevent the nosocomial transmission of emerging infectious diseases must correspond with community disease prevalence. Our data reinforce the importance of multi-time point surveillance of asymptomatic HCWs and routine surveillance of patients and caregivers during an epidemic.


Subject(s)
COVID-19/prevention & control , Cross Infection/prevention & control , Disease Outbreaks/prevention & control , Infection Control/methods , SARS-CoV-2 , COVID-19/transmission , Health Personnel , Hospitals, University , Humans , Prevalence , Republic of Korea/epidemiology , Retrospective Studies
9.
BMC Cancer ; 20(1): 803, 2020 Aug 24.
Article in English | MEDLINE | ID: mdl-32831058

ABSTRACT

BACKGROUND: Recently, the endothelial Activation and Stress Index (EASIX) score has been reported to predict overall survival (OS) after allogeneic stem cell transplantation. This study evaluated the prognostic role of EASIX score in patients with newly diagnosed multiple myeloma (MM). METHODS: This retrospective study analyzed the records of 1177 patients with newly diagnosed MM between February 2003 and December 2017 from three institutions in the Republic of Korea. Serum lactate dehydrogenase (LDH), creatinine, and platelet count at diagnosis were measured in all included patients. EASIX scores were calculated using the formula-LDH (U/L) × Creatinine (mg/dL) / platelet count (109/L) and were evaluated based on log2 transformed values. RESULTS: The median age of patients was 63 years (range, 22-92), and 495 patients (42.1%) underwent autologous stem cell transplantation (ASCT). The median log2 EASIX score at diagnosis was 1.1 (IQR 0.3-2.3). Using maximally selected log-rank statistics, the optimal EASIX cutoff value for OS was 1.87 on the log2 scale (95% CI 0.562-0.619, p < 0.001). After median follow-up for 50.0 months (range, 0.3-184.1), the median OS was 58.2 months (95% CI 53.644-62.674). Overall, 372 patients (31.6%) showed high EASIX scores at diagnosis, and had significantly inferior OS compared to those with low EASIX (log2 EASIX ≤1.87) (39.1 months vs. 67.2 months, p < 0.001). In multivariate Cox analysis, high EASIX was significantly associated with poor OS (HR 1.444, 95% CI 1.170-1.780, p = 0.001). In the subgroup analysis of patients who underwent ASCT, patients with high EASIX showed significantly inferior OS compared to those with low EASIX (52.8 months vs. 87.0 months, p < 0.001). In addition, in each group of ISS I, II, and III, high EASIX was associated with significantly inferior OS (ISS 1, 45.2 months vs. 76.0 months, p = 0.001; ISS 2, 42.3 months vs. 66.5 months, p = 0.002; ISS 3, 36.8 months vs. 55.1 months, p = 0.001). CONCLUSION: EASIX score at diagnosis is a simple and strong predictor for OS in patients with newly diagnosed MM.


Subject(s)
Hematopoietic Stem Cell Transplantation , Multiple Myeloma/therapy , Severity of Illness Index , Adult , Aged , Aged, 80 and over , Creatinine/blood , Endothelium/immunology , Female , Follow-Up Studies , Humans , Kaplan-Meier Estimate , L-Lactate Dehydrogenase/blood , Male , Middle Aged , Multiple Myeloma/diagnosis , Multiple Myeloma/immunology , Multiple Myeloma/mortality , Platelet Count , Prognosis , Reproducibility of Results , Republic of Korea/epidemiology , Retrospective Studies , Transplantation, Autologous , Treatment Outcome , Young Adult
10.
Langmuir ; 36(13): 3393-3403, 2020 04 07.
Article in English | MEDLINE | ID: mdl-32216370

ABSTRACT

Maintaining the integrity of cell membranes is indispensable for cellular viability. Poloxamer 188 (P188), a poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymer with a number-average molecular weight of 8700 g/mol and containing 80% by mass PEO, protects cell membranes from various external injuries and has the potential to be used as a therapeutic agent in diverse applications. The membrane protection mechanism associated with P188 is intimately connected with how this block copolymer interacts with the lipid bilayer, the main component of a cell membrane. Here, we report the distribution of P188 in a model lipid bilayer comprising 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine (POPC) using neutron reflectivity (NR) and atomic force microscopy (AFM). We also investigated the association of a PEO homopolymer (PEO8.4K; Mn = 8400 g/mol) that does not protect living cell membranes. These experiments were conducted following incubation of a 4.5 mmol/L polymer solution in a buffer that mimics physiological conditions with supported POPC bilayer membranes followed by washing with the aqueous medium. In contrast to previous reports, which dealt with P188 and PEO in salt-free solutions, both P188 and PEO8.4K penetrate into the inner portion of the lipid bilayer as revealed by NR, with approximately 30% by volume occupancy across the membrane without loss of bilayer structural integrity. These results indicate that PEO is the chemical moiety that principally drives P188 binding to bilayer membranes. No defects or phase-separated domains were observed in either P188- or PEO8.4K-incubated lipid bilayers when examined by AFM, indicating that polymer chains mingle homogeneously with lipid molecules in the bilayer. Remarkably, the breakthrough force required for penetration of the AFM tip through the bilayer membrane is unaffected by the presence of the large amount of P188 and PEO8.4K.


Subject(s)
Lipid Bilayers , Propylene Glycols , Polyethylene Glycols , Polymers
11.
Langmuir ; 34(23): 6703-6712, 2018 06 12.
Article in English | MEDLINE | ID: mdl-29787676

ABSTRACT

Poloxamer 188 (P188), a poly(ethylene oxide)- b-poly(propylene oxide)- b-poly(ethylene oxide) triblock copolymer, protects cell membranes against various external stresses, whereas poly(ethylene oxide) (PEO; 8600 g/mol) homopolymer lacks protection efficacy. As part of a comprehensive effort to elucidate the protection mechanism, we used surface plasmon resonance (SPR) to obtain direct evidence of binding of the polymers onto supported lipid bilayers. Binding kinetics and coverage of P188 and PEO were examined and compared. Most notably, PEO exhibited membrane association comparable to that of P188, evidenced by comparable association rate constants and coverage. This result highlights the need for additional mechanistic understanding beyond simple membrane association to explain the differential efficacy of P188 in therapeutic applications.


Subject(s)
Lipid Bilayers/chemistry , Polyethylene Glycols/chemistry , Propylene Glycols/chemistry , Surface Plasmon Resonance , Lipid Bilayers/metabolism , Polyethylene Glycols/metabolism , Propylene Glycols/metabolism
12.
Langmuir ; 34(4): 1767-1774, 2018 01 30.
Article in English | MEDLINE | ID: mdl-29278669

ABSTRACT

This work examines the development of primary neurons and astrocytes on thoroughly controlled functional groups. Negatively charged surfaces presenting carboxylate (COO-) or sulfonate (SO3-) groups prove beneficial to neuronal behavior, in spite of their supposed repulsive electrostatic interactions with cellular membranes. The adhesion and survival of primary hippocampal neurons on negatively charged surfaces are comparable to or slightly better than those on positively charged (poly-d-lysine-coated) surfaces, and neuritogenesis and neurite outgrowth are accelerated on COO- and SO3- surfaces. Moreover, such favorable influences of the negatively charged surfaces are only seen in neurons but not for astrocytes. Our results indicate that the in vitro developmental behavior of primary hippocampal neurons is sophisticatedly modulated by angstrom-sized differences in chemical structure or the charge density of the surface. We believe that this work provides new implications for understanding neuron-material interfaces as well as for establishing new ways to fabricate neuro-active surfaces.


Subject(s)
Astrocytes/cytology , Astrocytes/drug effects , Cell Adhesion/drug effects , Hippocampus/cytology , Neurons/cytology , Neurons/drug effects , Animals , Carboxylic Acids/chemistry , Carboxylic Acids/pharmacology , Cell Membrane/chemistry , Cell Membrane/drug effects , Rats , Rats, Sprague-Dawley , Static Electricity , Sulfonic Acids/chemistry , Sulfonic Acids/pharmacology , Surface Properties
13.
J Med Syst ; 42(10): 198, 2018 Sep 13.
Article in English | MEDLINE | ID: mdl-30215150

ABSTRACT

Tricyclic antidepressants are known as potentially inappropriate medications in the elderly. A notification issued in July 2015 in South Korea recommended caution while prescribing tricyclic antidepressants to the elderly. Further, since October 2015, the nationwide computerized drug utilization review monitoring system provides a pop-up window, on a real-time basis, whenever tricyclic antidepressants are prescribed to elderly outpatients. Therefore, we evaluated whether providing drug utilization review information was effective in reducing tricyclic antidepressant prescription to elderly outpatients. We used the Health Insurance Review and Assessment Service-Adult Patient Sample data from 2014 to 2016. Data related to the prescription of tricyclic antidepressants to outpatients aged 65 years or more were extracted. We determined the number of prescriptions per day per 100,000 elderly patients in each month, compared the average number of prescriptions before and after the drug utilization review information was provided, and evaluated the changes in the number of prescriptions by using an interrupted time series analysis. The average number of tricyclic antidepressant prescriptions per day per 100,000 elderly patients decreased from 76.6 (75.5 to 77.6) to 65.7 (64.5 to 66.9), a 14.2% reduction after the provision of drug utilization review information started. Following initiation of provision of drug utilization review information, there was an immediate drop of 9.2 tricyclic antidepressant prescriptions per day per 100,000 elderly patients, whereas there was no statistically significant change in trends. Providing the drug utilization review information on tricyclic antidepressant prescription for the elderly contributed to the reduction in tricyclic antidepressant prescriptions.


Subject(s)
Antidepressive Agents, Tricyclic , Antidepressive Agents , Drug Utilization Review , Aged , Aged, 80 and over , Drug Prescriptions , Drug Utilization , Humans , Republic of Korea
14.
Mol Pharm ; 14(7): 2333-2339, 2017 07 03.
Article in English | MEDLINE | ID: mdl-28538101

ABSTRACT

Block copolymers can be synthesized in an array of architectures and compositions to yield diverse chemical properties. The triblock copolymer Poloxamer 188 (P188), the family archetype, consisting of a hydrophobic poly(propylene oxide) core flanked by hydrophilic poly(ethylene oxide) chains, can stabilize cellular membranes during stress. However, little is known regarding the molecular basis of membrane interaction by copolymers in living organisms. By leveraging diblock architectural design, discrete end-group chemistry modifications can be tested. Here we show evidence of an anchor and chain mechanism of interaction wherein titrating poly(propylene oxide) block end group hydrophobicity directly dictates membrane interaction and stabilization. These findings, obtained in cells and animals in vivo, together with molecular dynamics simulations, provide new insights into copolymer-membrane interactions and establish the diblock copolymer molecular architecture as a valuable platform to inform copolymer-biological membrane interactions. These results have implications for membrane stabilizers in muscular dystrophy and for other biological applications involving damaged cell membranes.


Subject(s)
Polyethylene Glycols/chemistry , Polymers/chemistry , Animals , Cell Line , Hydrophobic and Hydrophilic Interactions , Male , Mice , Muscular Dystrophy, Duchenne/metabolism , Propylene Glycols/chemistry
15.
Biomacromolecules ; 18(7): 2090-2101, 2017 Jul 10.
Article in English | MEDLINE | ID: mdl-28535058

ABSTRACT

Poloxamer 188, a triblock copolymer of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO), protects cellular membranes from various stresses. Though numerous block copolymer variants exist, evaluation of alternative architecture, composition, and size has been minimal. Herein, cultured murine myoblasts are exposed to the stresses of hypotonic shock and isotonic recovery, and membrane integrity was evaluated by quantifying release of lactate dehydrogenase. Comparative evaluation of a systematic set of PEO-PPO diblock and PEO-PPO-PEO triblock copolymers demonstrates that the diblock architecture can be protective in vitro. Short PPO blocks hinder protection with >9 PPO units needed for protection at 150 µM and >16 units needed at 14 µM. Addition of a tert-butyl end group enhances protection at reduced concentration. When the end group and PPO length are fixed, increasing the PEO length improves protection. This systematic evaluation establishes a new in vitro screening tool for evaluating membrane-sealing amphiphiles and provides mechanistic insight to guide future copolymer design for membrane stabilization in vivo.


Subject(s)
Myoblasts/metabolism , Osmotic Pressure/drug effects , Polyethylene Glycols/pharmacology , Polypropylenes/pharmacology , Animals , Cell Line , Cell Survival/drug effects , Mice , Myoblasts/cytology , Polyethylene Glycols/chemistry , Polypropylenes/chemistry
17.
Angew Chem Int Ed Engl ; 56(36): 10702-10706, 2017 08 28.
Article in English | MEDLINE | ID: mdl-28544545

ABSTRACT

Lymphocytes, such as T cells and natural killer (NK) cells, have therapeutic promise in adoptive cell transfer (ACT) therapy, where the cells are activated and expanded in vitro and then infused into a patient. However, the in vitro preservation of labile lymphocytes during transfer, manipulation, and storage has been one of the bottlenecks in the development and commercialization of therapeutic lymphocytes. Herein, we suggest a cell-in-shell (or artificial spore) strategy to enhance the cell viability in the practical settings, while maintaining biological activities for therapeutic efficacy. A durable titanium oxide (TiO2 ) shell is formed on individual Jurkat T cells, and the CD3 and other antigens on cell surfaces remain accessible to the antibodies. Interleukin-2 (IL-2) secretion is also not hampered by the shell formation. This work suggests a chemical toolbox for effectively preserving lymphocytes in vitro and developing the lymphocyte-based cancer immunotherapy.


Subject(s)
Cell- and Tissue-Based Therapy , Immunotherapy , Neoplasms/therapy , T-Lymphocytes/drug effects , Titanium/pharmacology , Cell Survival/drug effects , Humans , Jurkat Cells , Neoplasms/immunology , T-Lymphocytes/cytology , T-Lymphocytes/immunology , Titanium/chemistry
18.
Small ; 12(9): 1148-52, 2016 Mar 02.
Article in English | MEDLINE | ID: mdl-26395860

ABSTRACT

Control over neurite orientation in primary hippocampal neurons is achieved by using interrupted, anisotropic micropillar arrays as a cell culture platform. Both neurite orientation and neurite length are controlled by a function of interpillar distance.


Subject(s)
Cell Movement , Neurites/metabolism , Animals , Anisotropy , Cells, Cultured , Hippocampus/cytology , Neurites/ultrastructure , Rats, Sprague-Dawley
19.
EMBO J ; 30(6): 1040-53, 2011 Mar 16.
Article in English | MEDLINE | ID: mdl-21317874

ABSTRACT

Ionizing radiation (IR) triggers adaptive changes in gene expression. Here, we show that survival after IR strongly depends on the checkpoint kinase Chk2 acting upon its substrate HuR, an RNA-binding protein that stabilizes and/or modulates the translation of target mRNAs. Microarray analysis showed that in human HCT116 colorectal carcinoma cells (WT), IR-activated Chk2 triggered the dissociation of virtually all of HuR-bound mRNAs, since IR did not dissociate HuR target mRNAs in Chk2-null (CHK2-/-) HCT116 cells. Accordingly, several HuR-interacting mRNAs encoding apoptosis- and proliferation-related proteins (TJP1, Mdm2, TP53BP2, Bax, K-Ras) dissociated from HuR in WT cells, but remained bound and showed altered post-transcriptional regulation in CHK2-/- cells. Use of HuR mutants that were not phosphorylatable by Chk2 (HuR(3A)) and HuR mutants mimicking constitutive phosphorylation by Chk2 (HuR(3D)) revealed that dissociation of HuR target transcripts enhanced cell survival. We propose that the release of HuR-bound mRNAs via an IR-Chk2-HuR regulatory axis improves cell outcome following IR.


Subject(s)
Antigens, Surface/metabolism , Epithelial Cells/radiation effects , Gene Expression Regulation , Protein Serine-Threonine Kinases/metabolism , RNA, Messenger/metabolism , RNA-Binding Proteins/metabolism , Radiation, Ionizing , Antigens, Surface/genetics , Cell Line , Cell Survival , Checkpoint Kinase 2 , ELAV Proteins , ELAV-Like Protein 1 , Gene Knockout Techniques , Humans , RNA-Binding Proteins/genetics
20.
Regul Toxicol Pharmacol ; 71(3): 478-83, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25666110

ABSTRACT

BACKGROUND: Propofol is an addictive drug, and the problem of its abuse and dependence has occurred. To compare the safety profiles of propofol and other similar anesthetics such as diazepam, lorazepam, and midazolam, we evaluated their uses and related adverse drug reactions (ADRs) using Korean Adverse Event Reporting System (KAERS) data. METHODS: The domestic consumption data and the ADR reports of four anesthetics from 2008 to 2012 were retrieved. ADR proportions were calculated using defined daily dose/1000 inhabitants/day (DID) for the denominator. The patient's characteristics were compared among the four drugs statistically, and the types of ADRs were analyzed. RESULTS: The consumption and ADR reports increased during the study period, particularly in the cases of propofol and midazolam. Lorazepam showed the highest overall and serious ADR proportions (220.81 reports/DID, 58.47 reports/DID, respectively); however, with respect to death proportion, propofol was the first (19.21 reports/DID). Also, ADRs related to drug addiction were mainly observed in the propofol group. CONCLUSIONS: Four anesthetics were different with regard to the consumption and proportion or the type of ADRs. The use of propofol increased more than 2 times, and propofol showed the highest ADR proportions in death and drug addiction cases among the four anesthetics.


Subject(s)
Anesthetics, Intravenous/adverse effects , Drug-Related Side Effects and Adverse Reactions/epidemiology , Propofol/adverse effects , Adolescent , Adult , Adverse Drug Reaction Reporting Systems , Aged , Anesthetics, Intravenous/supply & distribution , Child , Child, Preschool , Diazepam/adverse effects , Drug Utilization Review , Drug-Related Side Effects and Adverse Reactions/diagnosis , Drug-Related Side Effects and Adverse Reactions/mortality , Female , Humans , Infant , Infant, Newborn , Lorazepam/adverse effects , Male , Midazolam/adverse effects , Middle Aged , Propofol/supply & distribution , Republic of Korea/epidemiology , Risk Assessment , Risk Factors , Substance-Related Disorders/diagnosis , Substance-Related Disorders/epidemiology , Time Factors , Young Adult
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