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1.
J Am Chem Soc ; 145(16): 9029-9038, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37040606

ABSTRACT

Size-tunable semiconducting two-dimensional (2D) nanosheets from conjugated homopolymers are promising materials for easy access to optoelectronic applications, but it has been challenging due to the low solubility of conjugated homopolymers. Herein, we report size-tunable and uniform semiconducting 2D nanorectangles via living crystallization-driven self-assembly (CDSA) of a fully conjugated polyenyne homopolymer prepared by cascade metathesis and metallotropy (M&M) polymerization. The resulting polyenyne with enhanced solubility successfully underwent living CDSA via biaxial growth mechanism, thereby producing 2D nanorectangles with sizes precisely tuned from 0.1 to 3.0 µm2 with narrow dispersity mostly less than 1.1 and low aspect ratios less than 3.1. Furthermore, living CDSA produced complex 2D block comicelles with different heights from various degrees of polymerization (DPs) of unimers. Based on diffraction analyses and DFT calculations, we proposed an interdigitating packing model with an orthorhombic crystal lattice of semiconducting 2D nanorectangles.

2.
Fish Shellfish Immunol ; 68: 243-250, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28668485

ABSTRACT

Edwardsiella piscicida is a Gram-negative pathogen that generally causes lethal septicemia in marine and freshwater fish. We generated a E. piscicida CK216 Δcrp mutant to investigate various biological roles related to this organism, including pathogenesis. Lack of Crp in CK216 was demonstrated by immunoblotting using a Crp-specific antibody. Compared to the parental strain, the mutant exhibited changes in three biochemical phenotypes, including ornithine decarboxylation, citrate utilization, and H2S production. Complementation of crp deletion in trans rescued the phenotype of the parental strain. This study proved that hemolytic activity in E. piscicida is controlled by Crp. In addition, significantly reduced motility of E. piscicida CK216 was observed, which resulted from a lack of flagella synthesis. To examine the virulence in fish, E. piscicida cells were injected into the goldfish (Carassius auratus) via intraperitoneal route. The LD50 of CK216 was 9.25 × 108 CFU, while that of the CK108 parental strain was 9.24 × 105 CFU, attenuated 1000 fold in goldfish. Fish immunized with CK216 elicited IgM responses. Moreover, 80% of goldfish immunized with 1 × 106 CFU survived after administration of a lethal dose (1 × 107 CFU) of virulent E. piscicida CK41, suggesting the potential for E. piscicida CK216 to serve as a live attenuated vaccine in aquaculture.


Subject(s)
Bacterial Proteins/genetics , Cyclic AMP Receptor Protein/genetics , Edwardsiella , Enterobacteriaceae Infections/veterinary , Fish Diseases/immunology , Fish Diseases/microbiology , Goldfish , Animals , Bacterial Proteins/immunology , Cyclic AMP Receptor Protein/immunology , Edwardsiella/genetics , Edwardsiella/immunology , Edwardsiella/pathogenicity , Enterobacteriaceae Infections/immunology , Mutation , Virulence/genetics
3.
Anesth Analg ; 124(1): 204-213, 2017 01.
Article in English | MEDLINE | ID: mdl-27607480

ABSTRACT

BACKGROUND: Superoxide, nitric oxide (NO), and peroxynitrite are important mediators in the pathogenesis of ischemia-reperfusion (I/R) injury. We tested the renoprotective effects of allopurinol (ALP), a xanthine oxidase inhibitor, N-nitro-L-arginine methyl ester (L-NAME), and 5,10,15,20-tetrakis (N-methyl-4-pyridyl) porphyrinato iron (III) (FeTMPyP) by selective inhibition of superoxide, NO, and peroxynitrite, respectively. METHODS: Male Sprague-Dawley rats were randomly assigned to 5 groups (n = 6 per group). Group 1 was a sham-operated group. Group 2 was the renal I/R group (30-minute ischemia followed by 24-hour reperfusion). Rats in groups 3, 4, and 5 received ALP, L-NAME, or FeTMPyP, respectively, at 5 minutes before the reperfusion. Serum creatinine (Cr), blood urea nitrogen (BUN), renal tissue malondialdehyde, superoxide dismutase, histological changes, apoptosis, and monocyte infiltration were evaluated. In addition, the combined treatment with ALP and L-NAME was compared with FeTMPyP in a second independent experiment. RESULTS: The administration of ALP, L-NAME, and FeTMPyP diminished the increase in Cr (P = .0066 for all) and BUN (P = .0066 for ALP; and P = .013 for L-NAME) induced by I/R injury and decreased the histological damage (P = .0066 for all). In addition, ALP, L-NAME, and FeTMPyP attenuated the oxidative stress response as determined by a decrease in malondialdehyde level (P = .0066 for all), apoptotic renal tubular cells (P = .0066 for all), and monocyte infiltration (P = .0066 for all). The combined treatment of ALP and L-NAME decreased Cr and BUN levels to a greater degree than FeTMPyP (P = .016 for Cr; P = .0079 for BUN). CONCLUSIONS: Superoxide, NO, and peroxynitrite are involved in renal I/R injury. The reduction of peroxynitrite formation, via inhibition of superoxide or NO, or the induction of peroxynitrite decomposition may be beneficial in renal I/R injury.


Subject(s)
Allopurinol/pharmacology , Antioxidants/pharmacology , Enzyme Inhibitors/pharmacology , Kidney Diseases/prevention & control , Kidney/drug effects , Metalloporphyrins/pharmacology , NG-Nitroarginine Methyl Ester/pharmacology , Oxidative Stress/drug effects , Reperfusion Injury/prevention & control , Animals , Apoptosis/drug effects , Blood Urea Nitrogen , Creatinine/blood , Cytoprotection , Disease Models, Animal , Kidney/metabolism , Kidney/pathology , Kidney Diseases/metabolism , Kidney Diseases/pathology , Lipid Peroxidation/drug effects , Male , Monocytes/drug effects , Monocytes/metabolism , Nitric Oxide/metabolism , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/metabolism , Peroxynitrous Acid/metabolism , Rats, Sprague-Dawley , Reperfusion Injury/metabolism , Reperfusion Injury/pathology , Superoxides/metabolism , Xanthine Oxidase/antagonists & inhibitors , Xanthine Oxidase/metabolism
4.
J Korean Med Sci ; 29(2): 265-71, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24550656

ABSTRACT

The purpose of this study was to identify the differences in angiogenesis gene expression between normal and diabetic keratocytes stimulated with interleukin-1α (IL-1α) and tumor necrosis factor-α (TNF-α). Primarily cultured normal and diabetic keratocytes were treated with 20 ng/mL of IL-1a and TNF-α for 6 hr. cDNA was hybridized to an oligonucleotide microarray. Microarray analysis was used to identify differentially expressed genes that were further evaluated by real-time polymerase chain reaction (RT-PCR). Diabetes keratocytes overexpressed vital components of angiogenesis including Agtr1, and under-expressed components related to the blood vessel maturation, including Dcn. Cytokine-treated diabetic keratocytes differentially expressed components of angiogenesis. OLETF keratocytes after treatment with IL-1α and TNF-α showed the newly expressed 15 and 14 genes, respectively. Newly and commonly under-expressed five genes followed by treatment with both IL-1α and TNF-α were also evident. RT-PCR showed results similar to the microarray results. Agtr1 and Itga1 showed an increased expression in diabetic keratocytes compared with normal corneal keratocytes, especially after TNF-α treatment. Il6 appeared strong expression after interleukin-1α treatment, but showed down expression after TNF-α treatment. Further studies to analyze and confirm the significance of the identified angiogenetic genes of diabetes are needed.


Subject(s)
Keratinocytes/metabolism , Neovascularization, Physiologic/genetics , Oligonucleotide Array Sequence Analysis , Animals , Cells, Cultured , Gene Expression Regulation/drug effects , Interleukin-1alpha/pharmacology , Keratinocytes/cytology , Keratinocytes/drug effects , Rats , Real-Time Polymerase Chain Reaction , Receptor, Angiotensin, Type 1/genetics , Receptor, Angiotensin, Type 1/metabolism , Tumor Necrosis Factor-alpha/pharmacology
5.
Pain Pract ; 14(8): 752-6, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24750583

ABSTRACT

Lumbar spine transverse process fractures (LSTPFs) are uncommon and frequently overlooked on plain film radiographs. Even when recognized, they are often regarded as trivial and minimally painful injuries compared with combined serious major abdominal, pelvic, and spinal injuries. Conservative treatments are usually offered to patients with LSTPFs. This report presents 4 cases of LSTPFs where symptoms did not improve after more than 1 week of conservative management. Local anesthetics and steroids were injected directly into the fracture site under computed tomography guidance, referred to as a fracture site in situ block, in an attempt to accelerate the return to daily lives and professional activities. Three of the 4 patients returned to their daily lives almost immediately after completing the procedure. Although the procedure was appropriately performed at L4, 1 patient still complained of pain. This patient's all films were meticulously re-examined, and it was determined that a transverse process fracture was present at not only L4 but also L1. This report introduces a method of active treatment to help patients with LSTPFs quickly return to their daily lives and professional activities. The positive results in these cases suggest that fracture site in situ block might be a useful option for treating patients with LSTPFs.


Subject(s)
Lumbar Vertebrae/surgery , Spinal Fractures/surgery , Thoracic Vertebrae/surgery , Adult , Female , Humans , Lumbar Vertebrae/diagnostic imaging , Male , Middle Aged , Spinal Fractures/diagnostic imaging , Tomography, X-Ray Computed/methods , Treatment Outcome
6.
Pain Physician ; 27(1): 79-88, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38285038

ABSTRACT

BACKGROUND: In patients with severe cancer pain, systemic analgesics are often refractory or have limited application due to the side effects of opioids. In these cases, epidural analgesia may be effective. However, data on the effects of epidural patient-controlled analgesia (PCA) on cancer pain are limited. OBJECTIVES: To evaluate the analgesic efficacy of epidural PCA in patients with cancer pain through a retrospective chart review. STUDY DESIGN: Retrospective analysis. SETTING: A single academic center in Daegu, South Korea. METHODS: The analgesic efficacy of epidural PCA on cancer pain was analyzed in patients who underwent epidural PCA using a disposable balloon pump with a flow regulator between 2012 and 2021. The pump was filled with a 600-mL mixture of 6 ampoules of 0.2% ropivacaine, 1 mg fentanyl, and normal saline. For the first use of epidural PCA, the basal rate, bolus dose, and lockout time were set as 4 mL/h, 2 mL, and 15 min, respectively. The basal rate was increased and decreased depending on the degree of pain relief effect and occurrence of side effects, respectively. To increase the usage time of epidural PCA and reduce the patient's cost burden, the fentanyl dose was increased by 1 mg when the disposable balloon pump was replaced with a new one after exhaustion of the drug if no side effects from the previous dose were observed. Analgesic efficacy was confirmed by comparing the number of types and the total amount of opioids used in patients before and after epidural PCA application in terms of the equivalent dose of oral morphine. RESULTS: Epidural catheterization was performed 105 times, and PCA was refilled 257 times in 88 patients. On average, epidural catheterization was performed 1.2 ± 0.4 (1-3) times, and epidural PCA was refilled 3.2 ± 2.3 (1-11) times per patient. The mean duration of PCA use was 15.6 ± 13.4 (1-82) days. The mean number of opioid types used the day before the procedure and the mean smallest number of opioids used per day up to 5 days after the procedure were 3.4 ± 1.2 and 2.4 ± 1.4, respectively (P < 0.05). The total amount of opioids used the day before the procedure and the smallest total amount of opioids used per day up to 5 days after the procedure were converted into oral morphine equivalent doses, respectively, and the mean doses were 449.5 ± 555.9 and 331.9 ± 462.8 mg, respectively (P < 0.05). LIMITATIONS: The study results are the author's observations from a single center. Epidural PCA was performed only on hospitalized patients. Individual differences were not considered in the composition of drugs for PCA. Transmucosal immediate-release fentanyl was not accurately converted to oral morphine; thus, it was excluded from the analysis of the total amount used, and the effect of adjuvant analgesics could not be considered. CONCLUSION: Epidural PCA using subcutaneous tunneling is a useful cancer pain control method. Furthermore, it can be safely used for a longer duration owing to its low infection risk.


Subject(s)
Cancer Pain , Neoplasms , Humans , Analgesia, Patient-Controlled , Cancer Pain/drug therapy , Retrospective Studies , Analgesics , Analgesics, Opioid/therapeutic use , Fentanyl/therapeutic use , Pain , Morphine Derivatives , Neoplasms/complications
7.
Korean J Pain ; 37(2): 119-131, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38557654

ABSTRACT

There are growing concerns regarding the safety of long-term treatment with opioids of patients with chronic non-cancer pain. In 2017, the Korean Pain Society (KPS) developed guidelines for opioid prescriptions for chronic non-cancer pain to guide physicians to prescribe opioids effectively and safely. Since then, investigations have provided updated data regarding opioid therapy for chronic non-cancer pain and have focused on initial dosing schedules, reassessment follow-ups, recommended dosage thresholds considering the risk-benefit ratio, dose-reducing schedules for tapering and discontinuation, adverse effects, and inadvertent problems resulting from inappropriate application of the previous guidelines. Herein, we have updated the previous KPS guidelines based on a comprehensive literature review and consensus development following discussions among experts affiliated with the Committee on Hospice and Palliative Care in the KPS. These guidelines may assist physicians in prescribing opioids for chronic non-cancer pain in adult outpatient settings, but should not to be regarded as an inflexible standard. Clinical judgements by the attending physician and patient-centered decisions should always be prioritized.

8.
Nat Commun ; 15(1): 5632, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38965276

ABSTRACT

The power conversion efficiency of perovskite solar cells continues to increase. However, defects in perovskite materials are detrimental to their carrier dynamics and structural stability, ultimately limiting the photovoltaic characteristics and stability of perovskite solar cells. Herein, we report that 6H polytype perovskite effectively engineers defects at the interface with cubic polytype FAPbI3, which facilitates radiative recombination and improves the stability of the polycrystalline film. We particularly show the detrimental effects of shallow-level defect that originates from the formation of the most dominant iodide vacancy (VI+) in FAPbI3. Furthermore, additional surface passivation on top of the hetero-polytypic perovskite film results in an ultra-long carrier lifetime exceeding 18 µs, affords power conversion efficiencies of 24.13% for perovskite solar cells, 21.92% (certified power conversion efficiency: 21.44%) for a module, and long-term stability. The hetero-polytypic perovskite configuration may be considered as close to the ideal polycrystalline structure in terms of charge carrier dynamics and stability.

9.
Transplant Proc ; 55(10): 2478-2486, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37867004

ABSTRACT

BACKGROUND: Acute hyperglycemia frequently occurs in stressful situations, including liver transplantation or hepatic surgery, which may affect the protective effects of dexmedetomidine preconditioning and increase postoperative mortality. Therefore, this study aimed to investigate the effects of dexmedetomidine on hepatic ischemia-reperfusion injury in acute hyperglycemia. METHODS: Thirty-six Sprague-Dawley rats were randomly assigned to 6 groups, including a combination between 2 glycemic (normo- and hyperglycemia) and 3 ischemia-reperfusion conditions (sham, ischemia-reperfusion only, and dexmedetomidine plus ischemia-reperfusion). Dexmedetomidine 70 µg/kg was preconditioned 30 minutes before ischemic injury. After 6 hours of reperfusion, serum aminotransferase levels were measured to confirm the hepatic tissue injury. Furthermore, inflammatory (nuclear factor-κb, tumor necrosis factor-α, and interleukin-6) and oxidative stress markers (malondialdehyde and superoxide dismutase) were detected. RESULTS: Ischemia-reperfusion injury significantly increased the serum levels of aminotransferase and inflammatory and oxidative stress markers. These ischemia-reperfusion-induced changes were further exacerbated in hyperglycemia and were significantly attenuated by dexmedetomidine preconditioning. However, the effects of dexmedetomidine in hyperglycemia were lesser than those in normoglycemia (P < .05 for aminotransferases, inflammatory markers, malondialdehyde, and superoxide dismutase). CONCLUSIONS: These findings suggest that the protective effects of dexmedetomidine preconditioning may be intact against hepatic ischemia-reperfusion injury in acute hyperglycemia. Although its effects appeared to be relatively reduced, this may be because of the increase in oxidative stress and inflammatory response caused by acute hyperglycemia. To determine whether the effects of dexmedetomidine itself would be impaired in hyperglycemia, further study is needed.


Subject(s)
Dexmedetomidine , Hyperglycemia , Reperfusion Injury , Rats , Animals , Rats, Sprague-Dawley , Dexmedetomidine/pharmacology , Reperfusion Injury/etiology , Reperfusion Injury/prevention & control , Reperfusion Injury/pathology , Ischemia/complications , Liver/pathology , Hyperglycemia/complications , Transaminases , Malondialdehyde , Superoxide Dismutase
10.
J Nanosci Nanotechnol ; 12(7): 5160-3, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22966538

ABSTRACT

In this paper, we propose a method for simulating nanopore structure by using conventional 3-D simulation tool to mimic the I-V behavior of the nanopore structure. In the simulation, we use lightly doped silicon for ionic solution where some parameters like electron affinity and dielectric constant are fitted to consider the ionic solution. By using this method, we can simulate the I-V behavior of nanopore structure depending on the location and the size of the sphere shaped silicon oxide which is considered to be an indicator of a DNA base. In addition, we simulate an Ionic Field Effect Transistor (IFET) which has basically the nanopore structure, and show that the simulated curves follow sufficiently the I-V behavior of the measurement data. Therefore, we think it is reasonable to apply parameter modeling mentioned above to simulate nanopore structure. The key idea is to modify electron affinity of silicon which is used to mimic the KCl solution to avoid band bending and depletion inside the nanopore. We could efficiently utilize conventional 3-D simulation tool to simulate the I-V behavior of nanopore structures.


Subject(s)
Computer-Aided Design , Conductometry/instrumentation , DNA/chemistry , DNA/genetics , Nanostructures/chemistry , Nanotechnology/instrumentation , Sequence Analysis, DNA/instrumentation , DNA/analysis , Equipment Design , Equipment Failure Analysis , Imaging, Three-Dimensional , Models, Chemical , Molecular Conformation , Nanostructures/ultrastructure , Transistors, Electronic
11.
Medicine (Baltimore) ; 101(43): e31393, 2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36316835

ABSTRACT

BACKGROUND: Thyroidectomy is performed under general anesthesia using inhaled anesthetics such as sevoflurane or desflurane in many cases. The objective of this study was to investigate whether the incidence of postoperative pain and discomfort after thyroidectomy differed with the type of inhaled anesthetic. METHODS: Eighty-one female patients who underwent thyroidectomy were randomly assigned to the Sevo group (n = 42) or the Des group (n = 39). On the day of surgery and on the first, third, and seventh days after surgery, one registered nurse in charge of the entire questionnaire survey conducted the questionnaire assessment through face-to-face interviews or phone calls with the patients. The questionnaire evaluated the severity scores for seven items (sore throat, wound pain, nausea and vomiting, dizziness, occipital headache, posterior neck pain, and shoulder pain) regarding postoperative pain and discomfort experienced by patients and assessed which of these seven items caused the greatest discomfort to the patient on each day. RESULTS: Except for the severity score for dizziness on the day of surgery, the severity scores of postoperative pain and discomfort experienced by patients on the day of surgery and on the first, third, and seventh days after surgery showed no statistically significant differences between the two groups. In addition, on the day of surgery and on the first, third, and seventh days after surgery, patients reported that sore throat caused the greatest discomfort. CONCLUSION: In patients undergoing thyroidectomy under general anesthesia using sevoflurane or desflurane, except for dizziness on the day of surgery, no other manifestation of postoperative pain and discomfort was influenced by the type of inhaled anesthetic. Moreover, after thyroidectomy, postoperative sore throat caused the greatest discomfort to patients from the day of surgery to the seventh day after surgery.


Subject(s)
Anesthetics, Inhalation , Isoflurane , Methyl Ethers , Pharyngitis , Humans , Female , Sevoflurane , Desflurane , Anesthetics, Inhalation/adverse effects , Methyl Ethers/adverse effects , Isoflurane/adverse effects , Thyroidectomy/adverse effects , Prospective Studies , Dizziness , Pain, Postoperative/epidemiology , Pain, Postoperative/etiology
12.
Medicine (Baltimore) ; 101(41): e31168, 2022 Oct 14.
Article in English | MEDLINE | ID: mdl-36253971

ABSTRACT

BACKGROUND: Poorly controlled acute postoperative pain after laparoscopic nephrectomy may adversely affect surgical outcomes and increase morbidity rates. In addition, excessive use of opioids during surgery may slow postoperative endocrine and metabolic responses and cause opioid-related side effects and opioid-induced hyperalgesia. The purpose of this study was to evaluate the effect of ultrasound-guided transversus abdominis plane (TAP) block on the postoperative quality of recovery and intraoperative remifentanil requirement in laparoscopic nephrectomy. METHODS: Sixty patients who underwent laparoscopic nephrectomy were randomly divided into 2 groups: TAP and Control groups. After induction of anesthesia and before awakening from anesthesia, the TAP group was administered 40 mL of 0.375% ropivacaine and the Control group was administered 40 mL of normal saline to deliver ultrasound-guided TAP block using 20 mL of each of the above drugs. The main objectives of this study were to evaluate the effect of the TAP block on quality of recovery using the Quality of Recovery 40 (QoR-40) questionnaire and assessments of intraoperative remifentanil requirement. In addition, to evaluate the postoperative analgesic effect of the TAP block, the total usage time for patient-controlled analgesia (PCA) and the number of PCA bolus buttons used in both groups were analyzed. RESULTS: The QoR-40 score, measured when visiting the ward on the third day after surgery, was significantly higher in the TAP group (171.9 ±â€…23.1) than in the Control group (151.9 ±â€…28.1) (P = .006). The intraoperative remifentanil requirement was not significantly different between the groups (P = .439). In the TAP group, the frequency of bolus dose accumulation at 1, 2, 3, 6, 12, 24, 48, and 72 hours after surgery was low enough to show a significant difference, and the total usage time for PCA was long enough to show a significant difference. CONCLUSION: In conclusion, we determined that ultrasound-guided TAP block during laparoscopic nephrectomy improves the quality of postoperative recovery and is effective for postoperative pain control but does not affect the amount of remifentanil required for adequate anesthesia during surgery.


Subject(s)
Analgesics, Opioid , Laparoscopy , Abdominal Muscles , Double-Blind Method , Humans , Laparoscopy/adverse effects , Nephrectomy/adverse effects , Pain, Postoperative/chemically induced , Pain, Postoperative/drug therapy , Pain, Postoperative/prevention & control , Prospective Studies , Remifentanil , Ropivacaine , Saline Solution
13.
Article in English | MEDLINE | ID: mdl-36286548

ABSTRACT

Although various methods have been developed to disperse transition metal dichalcogenides (TMDCs) in aqueous environments, the methodology to generate stable TMDC dispersions remains challenging. Here, we developed a hierarchical van der Waals (vdW) heterostructure-based strategy to disperse few-layered TMDCs (WS2, MoS2, WSe2, and MoSe2) using both hexagonal boron nitride (hBN) and sodium cholate (SC) as synergistic vdW surfactants. By showing long-term stability of up to 3 years, the extinction spectra of these TMDC/hBN/SC dispersions exhibit the most blue-shifted excitonic transitions, low background extinction, good colloidal stability, and dispersion stability upon ultracentrifugation compared to other dispersion methods. Hierarchical stacking having TMDCs and hBN/SC as core and shell parts is probed by electrostatic/atomic force microscopy and zeta potential, and its origin was attributed to surface energy matches. Along with the synergetic effect between TMDCs and hBN, the blue shift was ascribed to compressive strain on the TMDCs caused by hBN wrapping. The results of transmission electron microscopy show that the TMDCs in the dispersions have defective, few-layered structures with flake sizes that are less than a few hundred nm2. Raman spectroscopy is used to study not only the existence of compressive strain but also various interlayer coupling between TMDC and hBN. The hierarchical structures of TMDC/hBN/SC are discussed in terms of surface energies and topographies. This method is invaluable to provide a general methodology to disperse various surface-corrugated dimensional materials for various dispersion-based applications.

14.
Nanomaterials (Basel) ; 12(10)2022 May 17.
Article in English | MEDLINE | ID: mdl-35630927

ABSTRACT

Understanding the long-term stability of MoS2 is important for various optoelectronic applications. Herein, we show that the long-term exposure to an oxygen atmosphere for up to a few months results in zigzag (zz)-directional line unzipping of the MoS2 basal plane. In contrast to exposure to dry or humid N2 atmospheres, dry O2 treatment promotes the initial formation of line defects, mainly along the armchair (ac) direction, and humid O2 treatment further promotes ac line unzipping near edges. Further incubation of MoS2 for a few months in an O2 atmosphere results in massive zz-directional line unzipping. The photoluminescence and the strain-doping plot based on two prominent bands in the Raman spectrum show that, in contrast to dry-N2-treated MoS2, the O2-treated MoS2 primarily exhibits hole doping, whereas humid-O2-treated MoS2 mainly exists in a neutral charge state with tension. This study provides a guideline for MoS2 preservation and a further method for generating controlled defects.

15.
Medicine (Baltimore) ; 100(19): e25866, 2021 May 14.
Article in English | MEDLINE | ID: mdl-34106636

ABSTRACT

RATIONALE: Inferior mesenteric plexus block is indicated for left-sided lower abdominal pain. However, in patients with terminal cancer, severe abdominal pain can prevent the patient from maintaining the necessary posture during the procedure, and considerable anatomic deformation owing to extensive growth, invasion, and metastasis of the tumor in the abdominal cavity can make the procedure difficult. In these cases, performing the procedures under computed tomography (CT) guidance can ensure greater safety and accuracy. PATIENT CONCERNS: A 63-year-old man was referred for severe left-sided lower abdominal pain. He was unable to lie prone owing to severe lower abdominal pain and right hip surgery performed 15 years ago. His visual analog scale score was 9 out of 10. DIAGNOSES: The patient had terminal pancreatic tail cancer. Compared with abdominal CT findings obtained 50 days ago, hepatic metastasis and peritoneal seeding were still present, infiltration to the tissues around the pancreas and retrogastric area was increased, and most of the abdominal aorta was encased. In addition, metastatic lymph nodes were identified in several areas on the left including the left para-aortic area. However, the lesion causing the pain could not be identified. Therefore, an inferior mesenteric plexus block was performed according to the patient's complaint. INTERVENTIONS: Epidural patient-controlled analgesia was performed first. The patient's pain consequently reduced to a certain level, and the prone position became possible to some extent, so a CT-guided inferior mesenteric plexus block was performed 2 days later. OUTCOMES: After the CT-guided inferior mesenteric plexus block, it became possible to control the patient's pain with a fentanyl patch 75 mcg/hour only, and his visual analog scale score was reduced to 4. After 4 weeks, the patient died without complaints of severe pain as before. LESSONS: CT-guided inferior mesenteric plexus block can be performed in patients with left-sided lower abdominal pain, enabling a safer and more accurate procedure especially in patients with terminal cancer who are unable to lie prone owing to severe lower abdominal pain or with considerable anatomic deformation due to extensive growth, invasion, and metastasis of the tumor in the abdominal cavity.


Subject(s)
Abdominal Pain/drug therapy , Autonomic Nerve Block/methods , Cancer Pain/drug therapy , Celiac Plexus , Humans , Lymphatic Metastasis , Male , Middle Aged , Pancreatic Neoplasms/complications , Tomography, X-Ray Computed
16.
Medicine (Baltimore) ; 100(30): e26799, 2021 Jul 30.
Article in English | MEDLINE | ID: mdl-34397737

ABSTRACT

RATIONALE: Vulvodynia is a common chronic gynecological disease that affects approximately 16% of women, although it is rarely diagnosed. However, no known effective treatment exists. The etiology of vulvodynia is unknown and may be heterogeneous and multifactorial, so it is difficult-if not impossible-to improve this condition using 1 treatment method. Reports have shown that vulvodynia has an element of neuropathic pain. Although the role of the sympathetic nervous system in neuropathic pain is controversial, sympathetic nerve blocks have long been used to treat patients with chronic pain giving good results. A ganglion impar block (GIB), a sympathetic nerve block technique, may effectively manage pain and discomfort in patients with vulvodynia. PATIENT CONCERNS: Four patients suffering from chronic vulvar pain for 6 months-10 years were referred by gynecologists. The gynecologists could not identify the cause of the chronic vulvar pain, and symptoms were not improving by conservative therapy with medication. Patients complained of various chronic vulvar pain or discomfort. The initial visual analog scale (VAS) scores were 8 or 9 out of 10, and Leeds assessment of neuropathic symptoms and signs pain scale score was more than 12 out of 24. The review of gynecological medical records confirmed whether they showed allodynia during the cotton swab test and hyperalgesia to pin-prick test. DIAGNOSES: All patients were diagnosed with vulvodynia. INTERVENTIONS: All patients were treated with a GIB, once in 2 patients, 3 times in 1 patient, and 4 times (1 alcoholic neurolysis) in the other patient, under fluoroscopic guidance. OUTCOMES: After the procedures, the VAS score and the leeds assessment of neuropathic symptoms and signs (LANSS) pain scale score were decreased to less than 2 and 5, respectively, in all patients. Follow-up observations for 6 months-2 years revealed that 2 patients' symptoms entirely or nearly entirely improved and did not require further treatment. The pain of the remaining patients were well controlled with medications only. LESSONS: GIB is a good treatment option for patients suffering from chronic pain and discomfort caused by vulvodynia.


Subject(s)
Nerve Block/methods , Vulvodynia/surgery , Adult , Aged , Analgesics/therapeutic use , Female , Humans , Middle Aged , Vulvodynia/drug therapy
17.
ACS Nano ; 14(8): 10655-10665, 2020 08 25.
Article in English | MEDLINE | ID: mdl-32806060

ABSTRACT

Although the multiwalled carbon nanotube (MWNT) is a promising material for use in the production of high electrical conductivity (σ) polymer nanocomposites, its tendency to aggregate and distribute randomly in a polymer matrix is a problematic issue. In the current study, we developed a highly conductive and monoclinically aligned MWNT-polyamide 6 (PA) nanocomposite containing interfacing flavin moieties. In this system, the flavin mononucleotide (FMN) initially serves as a noncovalent aqueous surfactant for individualizing MWNTs in the form of FMN-wrapped MWNTs (FMN-MWNT), and then partially decomposed FMN (dFMN) induces crystallization of the PA on the MWNTs. The results of experiments performed using material subjected to partial dissolution of PA matrix show that the nanocomposite PA-dFMN-MWNT, formed by melt extrusion of PA and dFMN-MWNT, contains a three-dimensional monoclinic MWNT network embedded in an equally monoclinic PA matrix. An increase in monoclinic network promoted by an increase in the content of MWNT increases σ of the nanocomposite up to 100 S/m, the highest value reported for a polymer-MWNT nanocomposite. X-ray diffraction along with transmission electron microscopy reveal that the presence of dFMN induces the formation of monoclinic PA on dFMN-MWNT. The high σ of the PA-dFMN-MWNT nanocomposite is also a consequence of a minimization of defect formation of MWNT by noncovalent functionalization. Hierarchical structural ordering, yet individualization of MWNTs, provides a viable strategy to improve the physical property of nanocomposites.

18.
Chem Commun (Camb) ; 56(67): 9624-9627, 2020 Aug 28.
Article in English | MEDLINE | ID: mdl-32815947

ABSTRACT

Poly(3,4-ethylenedioxythiophene) (PEDOT) is an important material widely used in electronics for its hole conducting property. A novel strategy for the synthesis of nanoparticulate PEDOT was developed by emulsion droplet electrochemistry. Taking advantage of the space confinement in emulsions, PEDOT nanoparticles were size controllable without use of a separate template. Potential applications were investigated by implementing the PEDOT nanoparticle decorated electrodes as a supercapacitor and a hole transport layer in an organic light emitting diode.

19.
Medicine (Baltimore) ; 98(15): e15159, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30985694

ABSTRACT

BACKGROUND: Despite recent advances in gastric cancer surgery, open gastrectomy is often needed to treat gastric cancer. Due to the large incision in the abdomen, the amount of opioid required during surgery increases and postoperative pain becomes worse. It is well known that postoperative pain has a negative impact on the patient's immune system. Herein, we performed an ultrasound-guided bilateral rectus sheath block (RSB) in patients undergoing open gastrectomy under general anesthesia and analyzed the analgesic effectiveness of RSB in open gastrectomy. METHODS: A total of 46 patients scheduled for open gastrectomy were randomly divided into 2 groups: Group A (n = 21) consisted of patients who received an RSB using 40 mL of 0.375% ropivacaine under ultrasound guidance and Group B (n = 20) consisted of patients who received an RSB using 40 mL of normal saline. An electronic injection pump was connected to each patient for patient-controlled analgesia (PCA) immediately after the skin closure. The amount of remifentanil required during the surgery was analyzed. After using PCA, data on the use of PCA bolus dose were extracted and analyzed using Excel. RESULTS: Group A used significantly less remifentanil (1021.4 ±â€Š172.0 µg) than group B (1415.0 ±â€Š330.6 µg; P = .03). The number of PCA bolus dose provided to the patients after surgery was significantly lower in group A (1 h: 1.14 ±â€Š0.9, 2 h: 0.85 ±â€Š0.7) than in group B (1 h: 1.85 ±â€Š0.7, 2 h: 1.45 ±â€Š1.0) until 2 hours after the surgery (1 h, P = .008; 2 h, P = .03), but after 3 hours, there were no significant differences between the 2 groups. CONCLUSIONS: If ultrasound-guided bilateral RSB with 40 mL of 0.35% ropivacaine is performed precisely in patients undergoing open gastrectomy, the requirement for remifentanil during surgery can be reduced. In addition, it significantly reduces the use of PCA bolus dose for acute postoperative pain within 2 hours after surgery.


Subject(s)
Anesthetics, Local/administration & dosage , Gastrectomy , Nerve Block , Pain, Postoperative/prevention & control , Pain, Procedural/drug therapy , Ropivacaine/administration & dosage , Analgesia, Patient-Controlled , Anesthesia, General , Double-Blind Method , Female , Humans , Male , Middle Aged , Pain, Postoperative/drug therapy , Ultrasonography, Interventional
20.
Scand J Urol ; 52(5-6): 389-394, 2018.
Article in English | MEDLINE | ID: mdl-30600754

ABSTRACT

BACKGROUND: Catheter-related bladder discomfort (C.R.B.D.) is a risk factor for emergence agitation and delirium in postoperative phase. It may be resistant to conventional analgesic therapy such as opioids. This study evaluated the role of preoperative treatment using intravenous 20 mg nefopam in reducing the incidence and severity of C.R.B.D. during the first postoperative 24 h after urinary catheterization when compared with placebo. METHODS: Seventy adult males undergoing elective transurethral resection of bladder tumor requiring urinary bladder catheterization intraoperatively were randomly divided into two groups of 35 patients. In the intervention group (Group N), intravenous 20 mg nefopam in 100 mL normal saline was administered before spinal anesthesia. The placebo group (Group P) received intravenous normal saline 100 mL instead. The incidence and severity of side-effects, including C.R.B.D. at 1, 2, 6, and 24 h after surgery, was evaluated. RESULTS: The incidence of C.R.B.D. was reduced in Group N compared with Group P during the first postoperative 24 h (6/33 [18.2%] vs 22/35 [62.9%], Group N vs Group P, p = .000). The severity of C.R.B.D. also varied significantly at postoperative 1, 2, and 6 h. The use of postoperative analgesics was reduced in Group N compared with Group P (8/33 [24.2%] vs 25/35 [71.4%], Group N vs Group P, p = .000). CONCLUSIONS: The preoperative administration of single-dose intravenous nefopam reduced the incidence and severity of C.R.B.D. in the early postoperative period in patients undergoing T.U.R.-B. under spinal anesthesia.


Subject(s)
Analgesics, Non-Narcotic/therapeutic use , Carcinoma, Transitional Cell/surgery , Cystoscopy/methods , Nefopam/therapeutic use , Pain, Postoperative/prevention & control , Urinary Bladder Neoplasms/surgery , Urinary Catheters/adverse effects , Aged , Carcinoma, Transitional Cell/pathology , Double-Blind Method , Humans , Incidence , Male , Middle Aged , Pain Measurement , Pain, Postoperative/epidemiology , Pain, Postoperative/etiology , Preoperative Care , Urinary Bladder Neoplasms/pathology , Urinary Catheterization/adverse effects
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