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1.
J Phys Chem Lett ; 15(12): 3317-3322, 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38520384

ABSTRACT

Acetonitrile (AN) electrolyte solutions display uniquely high ionic conductivities, of which the rationale remains a long-standing puzzle. This research delves into the solution species and ion conduction behavior of 0.1 and 3.0 M LiTFSI AN and propylene carbonate (PC) solutions via Raman and dielectric relaxation spectroscopies. Notably, LiTFSI-AN contains a higher fraction of free solvent uncoordinated to Li ions than LiTFSI-PC, resulting in a lower viscosity of LiTFSI-AN and facilitating a higher level of ion conduction. The abundant free solvent in LiTFSI-AN is attributed to the lower Li-solvation power of AN, but despite this lower Li-solvation power, LiTFSI-AN exhibits a level of salt dissociation comparable to that of LiTFSI-PC, which is found to be enabled by TFSI anions loosely bound to Li ions. This work challenges the conventional notion that high solvating power is a prerequisite for high-conductivity solvents, suggesting an avenue to explore optimal solvents for high-power energy storage devices.

2.
J Phys Chem Lett ; 11(24): 10382-10387, 2020 Dec 17.
Article in English | MEDLINE | ID: mdl-33237787

ABSTRACT

The marked difference in the ionic conductivities of linear carbonate (LC) electrolyte solutions despite their similar viscosities and permittivities is a long-standing puzzle. This study unraveled the critical impact of solvent conformational isomerism on salt dissociation in 0.1-3.0 M LiPF6 dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC) solutions using Raman and dielectric relaxation spectroscopies. The extent of salt dissociation in the LC solutions, which decreased in the order DMC > EMC > DEC, is closely related to the fraction of polar cis-trans LC conformers, as this conformer participates in Li ion solvation more readily than the nonpolar cis-cis counterpart. Our first-principles calculations corroborated that the cis-trans conformer facilitates free ion formation more than the cis-cis conformer, and the extent of this effect decreased in the order DMC > EMC > DEC. This study provides an avenue for the design of highly conductive electrolytes by exploiting the conformational isomerism of solvent molecules.

3.
Hip Int ; 30(5): 641-648, 2020 Sep.
Article in English | MEDLINE | ID: mdl-31280602

ABSTRACT

OBJECTIVE: To evaluate the predicting value of 99mTc-hydroxydiphosphonate (HDP) pinhole bone scan in development of osteonecrosis of femoral head (ONFH) in patients with femoral neck fracture after cannulated screw fixation. METHODS: Pinhole bone scan of patients with metallically fixed femoral neck fracture from 2001 to 2015 were retrospectively reviewed. Initial pinhole bone scan was obtained within 2-3 weeks after surgery. Findings of initial pinhole bone scan were divided in to 4 groups. Group CU included cold defect in affected femoral head, group HU with no cold defect. Group PP with increased uptake along the inserted screws and group PN with no increased uptake along the inserted screws. More than 6 months of follow-up with pinhole bone scan and clinico-radiological evidence for ONFH was reviewed. RESULTS: 72 patients (mean age 54.01 years, male 22, female 50) were included. 19 patients were in group CU, 53 in group HU. 60 patients were in group PP, 12 in group PN. During the follow-up, 13 patients were diagnosed as ONFH. 9 (47.36%) patients in group CU developed ONFH and 4 (7.5%) in group HU. 4 (6.66%) patients in group PP developed ONFH and 9 (75%) in group PN. CONCLUSIONS: To predict ONFH of femoral head followed by neck fracture, many imaging techniques with variable results were known. In this study, cold defect in early postoperative pinhole bone scans could predict ONFH, and loss of increased uptake along screw inserted site could be a strong indicative sign of ONFH. Further evaluation with a larger population is necessary.


Subject(s)
Femoral Neck Fractures/diagnostic imaging , Femoral Neck Fractures/surgery , Femur Head Necrosis/etiology , Fracture Fixation, Internal/adverse effects , Postoperative Complications/etiology , Adult , Bone Screws , Female , Femur Head/surgery , Femur Head Necrosis/diagnostic imaging , Humans , Male , Middle Aged , Postoperative Complications/diagnostic imaging , Predictive Value of Tests , Radiography , Radiopharmaceuticals , Retrospective Studies , Technetium Tc 99m Medronate/analogs & derivatives
4.
Hip Pelvis ; 31(1): 23-32, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30899712

ABSTRACT

PURPOSE: Isolated greater trochanteric (GT) fractures are often identified using plain radiography of patients with post-traumatic hip pain. In many cases, the fracture extends to form an occult intertrochanteric fracture. We conducted a study to determine the frequency of occult intertrochanteric fractures in patients diagnosed with isolated GT fractures using plain radiographs. MATERIALS AND METHODS: Among 3,017 individuals who visited our emergency department with a trauma-induced pertrochanteric femur fracture between July 2004 and March 2018, 100 patients diagnosed with isolated GT fractures using plain radiographs were retrospectively analyzed. Patients were divided into two groups, those with: i) isolated GT fractures (group A) and ii) occult intertrochanteric fractures (group B). In addition, plain radiographs, magnetic resonance imaging results, and treatment methods were further analyzed in each group. If surgery treatment was needed, it was performed by one surgeon, and in all cases, a 2-hole dynamic hip screw was used. RESULTS: Among the 100 cases of isolated GT fractures diagnosed using plain radiograph, additional examinations revealed that 10 (10.0%) were suffering from isolated GT fractures alone, while the remaining 90 (90.0%) were further diagnosed with occult intertrochanteric fracture. Gender, age, mechanism of injury, and bone mineral density did not correlate with fracture type. CONCLUSION: In our analysis, 90% of injuries initially diagnosed as isolated GT fractures were found to extend into occult intertrochanteric fractures upon further examination with additional imaging modalities. Therefore, additional evaluation should be performed to test for the potential presence of occult intertrochanteric fractures and to establish appropriate treatment plans.

5.
ACS Appl Mater Interfaces ; 11(1): 517-524, 2019 Jan 09.
Article in English | MEDLINE | ID: mdl-30525367

ABSTRACT

Most electrolytes for rechargeable Mg batteries require time-consuming conditioning or precycling process to achieve a fully reversible Mg deposition/dissolution, which hinders the normal operation of Mg batteries. This study details a simple and effective method for eliminating this conditioning behavior using heptamethyldisilazane (HpMS) as an electrolyte additive. It was found that the HpMS additive greatly increases the current density and Coulombic efficiency of Mg deposition/dissolution from the initial cycles in various sulfone and glyme solutions containing MgCl2 or Mg(TFSI)2. The beneficial effect of HpMS was ascribed to its ability to scavenge trace water in the electrolytes and remove Mg(OH)2 and Mg(TFSI)2-decomposition products from the Mg surface. Considering its applicability for a wide range of Mg electrolytes, the use of HpMS is expected to accelerate the development of practical Mg batteries.

6.
J Korean Neurosurg Soc ; 61(5): 618-624, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30196659

ABSTRACT

OBJECTIVE: We evaluated the clinical manifestation and surgical results following operative treatment of cubital tunnel syndrome (CuTS) caused by anconeus epitrochlearis (AE) muscle. METHODS: Among 142 patients who underwent surgery for CuTS from November 2007 to October 2015, 12 were assigned to the AE group based on discovery of AE muscle; 130 patients were assigned to the other group. We analyzed retrospectively; age, sex, dominant hand, symptom duration, and weakness in hand. Severity of the disease was evaluated using the Dellon classification and postoperative symptom were evaluated using disability of arm shoulder and hand (DASH) and visual analogue scale (VAS) scores. Surgery consisted of subfascial anterior transposition following excision of AE muscle. RESULTS: AE muscle was present in 8.5% of all patients, and was more common in patients who were younger and with involvement of their dominant hand; the duration of symptom was shorter in patients with AE muscle. All patients showed postoperative improvement in symptoms according to DASH and VAS scores. CONCLUSION: The possibility of CuTS caused by AE muscle should be considered when younger patients have rapidly aggravated and activity-related cubital tunnel symptoms with a palpable mass in the cubital tunnel area. Excision of AE muscle and anterior ulnar nerve transposition may be considered effective surgical treatment.

7.
J Palliat Med ; 20(1): 65-68, 2017 01.
Article in English | MEDLINE | ID: mdl-27898288

ABSTRACT

BACKGROUND: Objective Prognostic Score (OPS) was developed as an easy and simple prognosticating tool in South Korea. It has been validated retrospectively in a single center in South Korea. OBJECTIVE: We aimed to validate the OPS prospectively for advanced cancer inpatients in South Korea using a multicenter study. DESIGN: This was a prospective cohort study. SETTING/SUBJECTS: We enrolled 243 advanced cancer patients admitted in five palliative care units in South Korea from May 2013 till March 2015. Seven members of the Korean Palliative Medicine Research Network who are experts of palliative care led the study. MEASUREMENTS: Clinical variables (dyspnea/anorexia/performance status) and laboratory variables (total leukocyte counts/serum total bilirubin/serum creatinine/lactate dehydrogenase) were collected at the enrollment. Survival time was calculated as days from enrollment to death during admission. RESULTS: A total of 217 patients were included in the final analysis (feasibility: 89.3%). Survival time of the higher OPS group (OPS ≥3) and the lower OPS group (OPS <3) was 10.0 (95% confidence interval (CI) 7.72-12.28) days and 32.0 (95% CI 25.44-38.56) days, respectively. There were significant differences between the 2 groups (p < 0.001). Overall accuracy of OPS ≥3 for predicting survival less than three weeks was 71.0%. CONCLUSIONS: OPS was successfully validated using a prospective multicenter study in South Korea. It is a useful method to predict three-week survival of Korean inpatients with advanced cancer.


Subject(s)
Inpatients/statistics & numerical data , Neoplasms/mortality , Neoplasms/therapy , Palliative Care/methods , Prognosis , Adult , Aged , Aged, 80 and over , Cohort Studies , Female , Humans , Male , Middle Aged , Prospective Studies , Republic of Korea , Retrospective Studies , Survival Analysis
8.
Korean J Fam Med ; 36(2): 103-12, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25802691

ABSTRACT

BACKGROUND: To date, the medical environment has been undergoing continual changes. It is therefore imperative that clinicians recognize the changing trends in the degree of patient expectations for patient-centered care. We conducted this study to examine changes in the degree of patient expectations for patient-centered care and the related socio-demographic factors in a primary care setting over a 5-year period. METHODS: We evaluated patients' attitudes toward patient-centered care using the Patient-Practitioner Orientation Scale, which provides 'sharing' and 'caring' scores. The study included 359 and 468 patients in phase I (March-July, 2005) and II (March-July, 2010). We also examined the relationship of their changes to their socio-demographic factors. RESULTS: In phase II, as compared with phase I, the 'sharing' score was higher (3.67 ± 0.68 vs. 3.82 ± 0.44; P < 0.001) and 'caring' one was lower (4.01 ± 0.57 vs. 3.67 ± 0.58; P = 0.001). Further, 'sharing' and 'caring' scores were associated with age, monthly income, education level, marital status, and the functional health status of patients. CONCLUSION: These results would be of help for providing patient-centered care for patients because it makes clinicians are aware of the degree to which patients' expect it.

9.
Clin Biochem ; 42(15): 1504-11, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19563795

ABSTRACT

OBJECTIVES: This study was conducted to investigate the expression of cytokines and growth factors in disc specimens obtained from patients with herniated nucleus pulposus (HNP) and degenerated disc disease (DDD). DESIGN AND METHODS: MRI and Western blot analyses were performed to evaluate the levels of disc degeneration and the expression levels of cytokines and growth factors. RESULTS: The levels of TNF-alpha and IL-8 were significantly greater in the DDD group than in the HNP group, but no statistical differences were observed in the expression of IL-1beta, IL-6 and IL-12 between the HNP and DDD groups. In addition, the expression of TGF beta, VEGF and NGF was significantly higher in the DDD group than in the HNP group. CONCLUSION: The greater levels of cytokine and growth factor expression in the DDD group than in the HNP explain why discogenic patients usually have more severe back pain than patients with herniated discs.


Subject(s)
Cytokines/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Intervertebral Disc Degeneration/metabolism , Intervertebral Disc Displacement/metabolism , Spinal Diseases/metabolism , Adult , Aged , Female , Humans , Interleukin-12/metabolism , Interleukin-1beta/metabolism , Interleukin-6/metabolism , Interleukin-8/metabolism , Intervertebral Disc Degeneration/pathology , Intervertebral Disc Displacement/complications , Intervertebral Disc Displacement/pathology , Low Back Pain/etiology , Low Back Pain/metabolism , Low Back Pain/pathology , Male , Middle Aged , Nerve Growth Factor/metabolism , Spinal Diseases/complications , Spinal Diseases/pathology , Tumor Necrosis Factor-alpha/metabolism , Vascular Endothelial Growth Factor A/metabolism
10.
J Neurosci ; 27(42): 11412-5, 2007 Oct 17.
Article in English | MEDLINE | ID: mdl-17942735

ABSTRACT

Tissue damage and its downstream consequences are experimentally assayed by formaldehyde application, which indiscriminately modifies proteins and is presumed to cause pain through broadly acting mechanisms. Here we show that formaldehyde activates the ion channel TRPA1 and that TRPA1-deficient mice exhibit dramatically reduced formaldehyde-induced pain responses. 4-Hydroxynonenal, a reactive chemical produced endogenously during oxidative stress, and other related aldehydes also activate TRPA1 in vitro. Furthermore, painful responses to iodoacetamide, a nonspecific cysteine-alkylating compound, are abolished in TRPA1-deficient mice. Therefore, although these reactive chemicals modify many proteins, the associated pain appears mainly dependent on a single ion channel.


Subject(s)
Pain/chemically induced , Pain/metabolism , Transient Receptor Potential Channels/physiology , Aldehydes/toxicity , Animals , Cell Line , Formaldehyde/toxicity , Humans , Iodoacetamide/toxicity , Mice , Mice, Knockout , Pain Measurement/methods , TRPA1 Cation Channel , Transient Receptor Potential Channels/deficiency , Transient Receptor Potential Channels/genetics
11.
Neurosci Res ; 59(1): 51-9, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17588699

ABSTRACT

There are several reports indicating that the locus coeruleus (LC) is capable of altering immune responses. Moreover, it is well established that the LC is the major source of descending noradrenergic system. Recently we have demonstrated that subcutaneous bee venom (BV) injection dramatically suppressed peripheral inflammation through activation of sympathetic preganglionic neurons (SPNs) leading to release of adreno-medullary catecholamines. Importantly, this 'BV-induced anti-inflammatory effect' (BVAI) is also associated with an increase of the activity of LC. Based on these data, present study examined whether BV-induced LC activation increased the activity of SPNs and this pathway played a role in BVAI using a zymosan-induced inflammatory air pouch model in mice. Unilateral BV injection into left hind limb produced anti-inflammation and specifically increased Fos expression in SPNs of the T7-T11 (which mainly project to adrenal medulla), but not those of the T1-T6 or T12-L2 spinal cord. 6-Hydroxydopamine-induced unilateral lesion of the contralateral, but not ipsilateral (to the BV injection site) LC significantly blocked BVAI and BV-induced Fos expression in SPNs. Additionally, intrathecal administration of idazoxan (alpha2-adrenoceptor antagonist), blocked BVAI. These results indicate that BV-induced activation of the contralateral LC-descending noradrenergic pathway increased the activity of SPNs that project to the adrenal medulla and this pathway is necessary for BVAI.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Bee Venoms/administration & dosage , Inflammation/drug therapy , Locus Coeruleus/physiopathology , Neurons/physiology , Spinal Cord/physiopathology , Sympathetic Fibers, Postganglionic/pathology , Animals , Choline O-Acetyltransferase/metabolism , Disease Models, Animal , Dose-Response Relationship, Drug , Drug Interactions , Functional Laterality , Inflammation/pathology , Injections, Spinal/methods , Locus Coeruleus/drug effects , Male , Mice , Mice, Inbred ICR , Neural Pathways/drug effects , Neural Pathways/physiopathology , Neurons/drug effects , Oncogene Proteins v-fos/metabolism , Oxidopamine/pharmacology , Spinal Cord/drug effects , Sympatholytics/pharmacology
12.
Curr Biol ; 15(10): 929-34, 2005 May 24.
Article in English | MEDLINE | ID: mdl-15916949

ABSTRACT

Garlic's pungent flavor has made it a popular ingredient in cuisines around the world and throughout history. Garlic's health benefits have been elevated from folklore to clinical study. Although there is some controversy as to the efficacy of garlic, garlic products are one of the most popular herbal supplements in the U.S. Chemically complex, garlic contains different assortments of sulfur compounds depending on whether the cloves are intact, crushed, cooked, or raw. Raw garlic, when cut and placed on the tongue or lips, elicits painful burning and prickling sensations through unknown mechanisms. Here, we show that raw but not baked garlic activates TRPA1 and TRPV1, two temperature-activated ion channels that belong to the transient receptor potential (TRP) family. These thermoTRPs are present in the pain-sensing neurons that innervate the mouth. We further show that allicin, an unstable component of fresh garlic, is the chemical responsible for TRPA1 and TRPV1 activation and is therefore likely to cause garlic's pungency.


Subject(s)
Calcium Channels/drug effects , Garlic/chemistry , Ion Channels/metabolism , Neurons/drug effects , Sulfinic Acids/pharmacology , Animals , Ankyrins , CHO Cells , Calcium Channels/metabolism , Cells, Cultured , Cricetinae , Cricetulus , Disulfides , Dose-Response Relationship, Drug , Electrophysiology , Fluorometry , Magnetic Resonance Spectroscopy , Neurons/metabolism , Plant Extracts , Rats , Sulfinic Acids/metabolism , TRPA1 Cation Channel , TRPC Cation Channels , TRPV Cation Channels
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