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1.
Math Biosci Eng ; 19(6): 6317-6330, 2022 04 19.
Article in English | MEDLINE | ID: mdl-35603403

ABSTRACT

Mathematical modeling of epidemic diseases is increasingly being used to respond to emerging diseases. Although conditions modeled by SIS dynamics will eventually reach either a disease-free steady-state or an endemic steady state without interventions, it is desirable to eradicate the disease as quickly as possible by introducing a control scheme. Here, we investigate the control methods of epidemic models on dynamic networks with temporary link deactivation. A quick link deactivation mechanism can simulate a community effort to reduce the risk of infection by temporarily avoiding infected neighbors. Once infected individuals recover, the links between the susceptible and recovered are activated. Our study suggests that a control scheme that has been shown ineffective in controlling dynamic network models may yield effective responses for networks with certain types of link dynamics, such as the temporary link deactivation mechanisms. We observe that a faster and more effective eradication could be achieved by updating control schemes frequently.


Subject(s)
Communicable Diseases , Epidemics , Communicable Diseases/epidemiology , Disease Susceptibility/epidemiology , Disease-Free Survival , Humans , Models, Biological , Models, Theoretical
2.
PLoS One ; 16(10): e0258163, 2021.
Article in English | MEDLINE | ID: mdl-34634051

ABSTRACT

We investigate the effect of board gender diversity on managerial risk-taking incentives. Our results demonstrate that companies with stronger board gender diversity provide more powerful executive risk-taking incentives. It appears that female directors' risk aversion exacerbates managers' risk aversion, resulting in a sub-optimal level of risk-taking. To offset this tendency for too little risk, companies are induced to provide stronger risk-taking incentives. Specifically, an increase in board gender diversity by one standard deviation raises vega by 10.3%. Further analysis corroborates the results, including propensity score matching, entropy balancing, and an instrumental-variable analysis. Endogeneity appears to be unlikely, suggesting that female directors are not merely associated with, but probably bring about stronger risk-taking incentives.


Subject(s)
Gender Identity , Motivation , Risk-Taking , Cities , Entropy , Female , Geography , Humans , Male , Propensity Score , Regression Analysis
3.
Medicine (Baltimore) ; 98(29): e16262, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31335674

ABSTRACT

RATIONALE: The thoracic epidural block and thoracic paravertebral block are widely used techniques for multimodal analgesia after thoracic surgery. However, they have several adverse effects, and are not technically easy. Recently, the erector spinae plane block (ESPB), an injected local anesthetic deep to the erector spinae muscle, is a relatively simple and safe technique. PATIENT CONCERNS: Three patients were scheduled for video assisted thoracoscopic lobectomy with mediastinal lymph node dissection. All the patients denied any past medical history to be noted. DIAGNOSES: They were diagnosed with primary adenocarcinoma requiring lobectomy of lung. INTERVENTIONS: The continuous ESPB was performed at the level of the T5 transverse process. The patient was received the multimodal analgesia consisted of oral celecoxib 200 mg twice daily, intravenous patient-controlled analgesia (Fentanyl 700 mcg, ketorolac 180 mg, total volume 100 ml), and local anesthetic (0.375% ropivacaine 30 ml with epinephrine 1:200000) injection via indwelling catheter every 12 hours for 5 days. Additionally, we injected a mixture of ropivacaine and contrast through the indwelling catheter for verifying effect of ESPB and performed Computed tomography 30 minutes later. OUTCOMES: The pain score was maintained below 3 points for postoperative 5 days, and no additional rescue analgesics were administered during this period. In the computed tomography, the contrast spread laterally from T2-T12 deep to the erector spinae muscle. On coronal view, the contrast spread to the costotransverse ligament connecting the rib and the transverse process. In the 3D reconstruction, the contrast spread from T6-T10 to the costotransverse foramen. LESSONS: Our contrast imaging data provides valuable information about mechanism of ESPB from a living patient, and our report shows that ESPB can be a good option as a multimodal analgesia after lung lobectomy.


Subject(s)
Adenocarcinoma of Lung , Adjuvants, Anesthesia , Lung Neoplasms , Nerve Block/methods , Pain, Postoperative/therapy , Paraspinal Muscles/physiopathology , Pneumonectomy , Ropivacaine/administration & dosage , Adenocarcinoma of Lung/pathology , Adenocarcinoma of Lung/surgery , Adjuvants, Anesthesia/administration & dosage , Adjuvants, Anesthesia/classification , Aged , Analgesia, Patient-Controlled/methods , Anesthetics, Local/administration & dosage , Combined Modality Therapy/methods , Female , Humans , Lung Neoplasms/pathology , Lung Neoplasms/surgery , Middle Aged , Pain Management/methods , Pain, Postoperative/diagnosis , Pain, Postoperative/etiology , Pain, Postoperative/physiopathology , Pneumonectomy/adverse effects , Pneumonectomy/methods , Thoracoscopy/adverse effects , Thoracoscopy/methods , Treatment Outcome , Ultrasonography, Interventional/methods
4.
Medicine (Baltimore) ; 98(20): e15654, 2019 May.
Article in English | MEDLINE | ID: mdl-31096490

ABSTRACT

RATIONALE: The most commonly used regional techniques for analgesia following laparotomy thoracic epidural analgesia and paravertebral blocks are technically difficult to perform and carry a risk of severe complications. Recently, the erector spinae plane block (ESPB) has been reported to effectively treat neuropathic pain. The ultrasound-guided ESPB is an easily performed fascial plane block that can provide sensory blockade from T2-4 to T12-L1. Moreover, the ESPB reportedly blocks both the ventral rami of spinal nerves and the rami communicants, which contain sympathetic nerve fibres, through spread into the thoracic paravertebral space. PATIENT CONCERNS: We report the case of a 35-year-old female patient who underwent excision of a larger ovarian mass via laparotomy with a wide, midline incision from the xiphoid process to the pubic tubercle. DIAGNOSES: They were diagnosed with mucinous cystadenoma originated from the right ovary and fallopian tube, and a right oophorectomy and salpingectomy were performed. INTERVENTIONS: The ESPB was performed for postoperative pain control at the level of the T8 transverse process. Postoperative multimodal analgesia was provided according to the acute pain service protocol of our hospital. The patient was prescribed oral acetaminophen 175 mg every 6 hours and intravenous patient-controlled analgesia (PCA) with fentanyl 7 µg/mL. A 1:1 mixture of 0.75% ropivacaine (20 mL) and saline (20 mL) with epinephrine (1: 200,000) was manually injected through the indwelling catheter every 8 hours (20 mL per side). OUTCOMES: The first demand dose of fentanyl was administered at 9 hours and 39 minutes after the surgery. There were no reported resting pain scores >4, nor were any rescue analgesics needed during the first 5 postoperative days. LESSONS: The ESPB provided highly effective analgesia as a part of multimodal analgesia after laparotomy with a wide midline incision.


Subject(s)
Laparotomy/adverse effects , Nerve Block/methods , Pain, Postoperative/drug therapy , Adult , Cystadenoma, Mucinous/surgery , Female , Humans , Ovarian Neoplasms/surgery , Ovariectomy/adverse effects , Pain Management/methods , Salpingectomy/adverse effects , Ultrasonography, Interventional
6.
Environ Pollut ; 237: 878-886, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29525083

ABSTRACT

This study incorporated stable isotope analyses with chemical analyses to determine the origin and migration of sulfur sources in East Asia, and these findings were compared with our decadal research from 2000 to 2001 and 2002 to 2003. The multiple sulfur isotope composition (32S, 33S and 34S) of the dissolved sulfate in precipitation was first measured from 2011 to 2013 in Seoul, South Korea. The δ34Snss values were -1.1‰ to 7.9‰ (avg. 3.6‰), strongly suggesting that sulfur derived from the combustion of Chinese coal is the predominant source of sulfate in the Seoul region. Low NO3/SO42- ratios in the precipitation samples indicated an insignificant effect of sulfur from vehicle exhaust. The seasonal variation of δ34Snss values appears to be caused by increasing biogenic sulfur activity during the spring and summer seasons. The some Δ33S values (0.13‰-0.16‰) measured in the three samples were sufficiently small; thus, whether these values can be attributed to mass-independent fractionation remains unclear. Measuring the Δ33S anomalies in dissolved sulfate provides valuable insights for identifying the sources of sulfur transferred from the stratosphere to the troposphere and upper troposphere.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring , Sulfates/analysis , Asia, Eastern , Republic of Korea , Seasons , Seoul , Sulfur/analysis , Sulfur Isotopes/analysis
7.
J Anesth ; 30(2): 320-3, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26721827

ABSTRACT

General anesthesia and central neuraxial blockades in patients with severe Duchenne muscular dystrophy are associated with high risks of complications, including rhabdomyolysis, malignant hyperthermia, hemodynamic instability, and postoperative mechanical ventilation. Here, we describe peripheral nerve blocks as a safe approach to anesthesia in a patient with severe Duchenne muscular dystrophy who was scheduled to undergo surgery. A 22-year-old male patient was scheduled to undergo reduction and internal fixation of a left distal femur fracture. He had been diagnosed with Duchenne muscular dystrophy at 5 years of age, and had no locomotive capability except for that of the finger flexors and toe extensors. He had developed symptoms associated with dyspnea 5 years before and required intermittent ventilation. We blocked the femoral nerve, lateral femoral cutaneous nerve, and parasacral plexus under ultrasound on the left leg. The patient underwent a successful operation using peripheral nerve blocks with no complications. In conclusion general anesthesia and central neuraxial blockades in patients with severe Duchenne muscular dystrophy are unsafe approaches to anesthesia because of hemodynamic instability and respiratory depression. Peripheral nerve blocks are the best way to reduce the risks of critical complications, and are a safe and feasible approach to anesthesia in patients with severe Duchenne muscular dystrophy.


Subject(s)
Anesthetics/administration & dosage , Muscular Dystrophy, Duchenne/surgery , Nerve Block/methods , Anesthesia, General/adverse effects , Femoral Nerve , Humans , Male , Nerve Block/adverse effects , Risk , Young Adult
8.
Sci Rep ; 5: 11681, 2015 Jun 26.
Article in English | MEDLINE | ID: mdl-26114224

ABSTRACT

The determination of the crustal structure is essential in geophysics, as it gives insight into the geohistory, tectonic environment, geohazard mitigation, etc. Here we present the latest advance on three-dimensional modeling representing the Tibetan Mohorovicic discontinuity (topography and ranges) and its deformation (fold), revealed by analyzing gravity data from GOCE mission. Our study shows noticeable advances in estimated Tibetan Moho model which is superior to the results using the earlier gravity models prior to GOCE. The higher quality gravity field of GOCE is reflected in the Moho solution: we find that the Moho is deeper than 65 km, which is twice the normal continental crust beneath most of the Qinghai-Tibetan plateau, while the deepest Moho, up to 82 km, is located in western Tibet. The amplitude of the Moho fold is estimated to be ranging from -9 km to 9 km with a standard deviation of ~2 km. The improved GOCE gravity derived Moho signals reveal a clear directionality of the Moho ranges and Moho fold structure, orthogonal to deformation rates observed by GPS. This geophysical feature, clearly more evident than the ones estimated using earlier gravity models, reveals that it is the result of the large compressional tectonic process.

9.
Mol Med Rep ; 10(1): 292-300, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24736893

ABSTRACT

Intravenous (IV) infusion of oleic acid (OA) distributes OA microemboli in the pulmonary capillaries, which results in severe vascular congestion, hemorrhage vascular congestion, interstitial edema, intravascular coagulation and bleeding. The immune response to acute lung injury (ALI) is known to be associated with rapid and widespread changes in microRNA (miRNA) expression in the lung. The present study of a model of rat lung injury aimed to investigate how the lung miRNA profile changes to mediate ALI. For the induction of ALI, OA (200 µl/kg) suspended in 20% ethyl alcohol was injected through the tail vein for 20 min. Lung tissue samples were acquired at 3, 6 and 24 h, and miRNA microarray and quantitative polymerase chain reaction were performed using these samples. The activation of phosphatase and tensin homolog (PTEN), protein kinase B (Akt), extracellular signal-regulated kinases (ERK) and c-Jun N-terminal kinases (JNK) were analyzed by western blot analysis. There were 75 miRNAs that demonstrated >1.5­fold changes in expression levels. miR-101a was highly upregulated at 3 h. miR-21 was upregulated in the OA group throughout the 24 h following OA challenge. miR-1 was the most downregulated miRNA at 24 h. In order to examine the expression levels of PTEN and Akt as targets of miR-21, western blot analysis was performed. At 3 h, the levels of PTEN were attenuated in the OA group as compared with those in the control group; however, p-Akt/Akt levels were increased at 3 h for the OA group. PTEN and p-Akt/Akt were significantly higher in the OA group at 3 h and were rapidly decreased at 6 h. The immunohistochemical stain of α-smooth muscle actin in the bronchial and alveolar wall increased 24 h after OA­induced ALI. These results indicated that the profile of miRNAs dynamically changed throughout the OA-induced ALI process, and mitogen-activated protein kinase activation, PTEN/Akt pathway alteration and smooth muscle actin activation were observed in this ALI model.


Subject(s)
Acute Lung Injury/etiology , MicroRNAs/metabolism , Oleic Acid/toxicity , 3' Untranslated Regions , Actins/metabolism , Acute Lung Injury/metabolism , Acute Lung Injury/pathology , Animals , Disease Models, Animal , Down-Regulation/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , Interleukin-13/metabolism , JNK Mitogen-Activated Protein Kinases/metabolism , Lung/metabolism , Male , PTEN Phosphohydrolase/genetics , PTEN Phosphohydrolase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects , Up-Regulation/drug effects
10.
J Surg Res ; 188(1): 280-9, 2014 May 01.
Article in English | MEDLINE | ID: mdl-24560349

ABSTRACT

BACKGROUND: Despite considerable evidence showing the immunosuppressive properties of mesenchymal stem cells (MSCs) in vitro, such properties have not been fully demonstrated in vivo. The aim of this study was to evaluate the effect of MSCs and/or MSC secretome in inducing tolerance in a mouse skin transplantation model. METHODS: After receiving full-thickness skin allotransplantation on the back of the mouse, the recipient mice were infused with phosphate-buffered saline, adipose tissue-derived stem cells (ASCs), conditioned media (CM), and control media. Specifically, ASCs (1.0 × 10(6)/0.1 mL) were transplanted to ASC-infused mice and 25-fold concentrated CM, which had been obtained from ASC culture were infused to CM-infused mice. Graft survival rates and the parameters reflecting immunologic consequences were assessed. RESULTS: The serum level of proinflammatory cytokine interleukin 6 decreased in mice treated with ASCs or CM compared with the control groups after infusion (P < 0.05). Interferon gamma, interleukin 10, and tumor necrosis factor alpha messenger RNA levels in the skin graft seemed to be decreased in the ASC-infused mice and CM-infused mice. Hyporesponsiveness was identified in mixed lymphocyte reaction assay at 30-d posttransplantation in ASC- or CM-infused mice. And, administering ASCs and CM markedly increased skin allograft survival compared with control animals (P < 0.001). CONCLUSIONS: These findings suggest that ASCs and their secretome have the potential to induce immunologic tolerance. Moreover, our results demonstrate that the immunosuppressive properties of ASCs are mediated by the ASC secretome. Our approach could provide insights into a promising strategy to avoid toxicities of chemical immunosuppressive regimen in solid organ transplantation.


Subject(s)
Immunosuppression Therapy/methods , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/metabolism , Skin Transplantation , Transplantation Tolerance , Adipose Tissue/cytology , Animals , Culture Media, Conditioned , Graft Survival , Humans , Interleukin-6/blood , Lymphocytes/physiology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Transplantation, Homologous , Transplants/cytology
12.
Knee Surg Sports Traumatol Arthrosc ; 20(12): 2573-8, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22434159

ABSTRACT

PURPOSE: Postoperative pain in arthroscopic shoulder surgery cannot be easily controlled with analgesics and nerve blocks. This study shows the analgesic effect of interscalene block (ISB) and suprascapular nerve block and axillary nerve block (SSNB + ANB) in patients under patient controlled analgesia (PCA). METHODS: Sixty-one patients (26 men and 35 women) who underwent arthroscopic rotator cuff repair were selected and allocated non-randomly to one of three groups: PCA only-group, PCA with ISB-group and PCA with SSNB + ANB-group. Visual analogue scale (VAS) score, degree of satisfaction, PCA usage and incidence of nausea and vomiting were evaluated at the recovery room, 8, 16 and 24 postoperative hours. RESULTS: The VAS score of the PCA only-group was highest at the recovery room. The VAS score of the PCA with ISB-group was the lowest, however, with large fluctuations over time. Although the VAS score of the PCA with SSNB + ANB-group was higher than that of the PCA with ISB-group, it was steadily lower than the PCA-only group, without any fluctuations. The degree of satisfaction of the PCA with ISB-group was highest at the recovery room. The number of times the PCA was used at the 8-h postoperative evaluation was largest in the PCA only-group. CONCLUSIONS: The initial 24 h after surgery plays a key role in controlling pain after arthroscopic shoulder surgery. PCA with SSNB + ANB is a better anaesthetic choice than PCA with ISB or PCA only during the initial 24 h of the postoperative period. LEVEL OF EVIDENCE: Clinical study, Level II.


Subject(s)
Analgesia, Patient-Controlled/methods , Arthroscopy/methods , Nerve Block/methods , Pain Management/methods , Pain, Postoperative/surgery , Shoulder Joint/surgery , Aged , Female , Humans , Male , Middle Aged , Prospective Studies , Treatment Outcome
13.
J Shoulder Elbow Surg ; 20(7): 1061-8, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21839653

ABSTRACT

HYPOTHESIS: The combination of suprascapular nerve block (SSNB) and axillary nerve block (ANB) has been reported to provide safe and effective analgesia for arthroscopic shoulder surgery. This study was designed to identify anatomic landmarks of the suprascapular nerve (SSN) and axillary nerve (AN) and to evaluate the effects of SSNB and ANB using the identified landmarks. MATERIALS AND METHODS: This study included 52 cadaveric shoulders and 30 patients in the anatomic and clinical studies, respectively. After the exact location of the SSN and AN was identified from the cadavers, the clinical study at the end of the operation and at 8, 16, 24, 32, 40, and 48 hours postoperatively was performed in 2 groups: without both SSNB and ANB (group I) and with both SSNB and ANB (group II). RESULTS: The SSN was located at a length of one-half (2/5-3/5, 88%) from the anterior tip of the acromion to the superior angle of the scapula and at a length of two-fifths (1/3-1/2, 100%) from the anterior tip of the acromion to the medial border of the spine. The AN was located at a length of three-fifths (2/5-4/5, 98%) from the acromial angle to the inferior insertion of the teres major muscle. The depth from the skin was 3.20 ± 0.58 cm for the SSN and 2.07 ± 0.45 cm for the AN. The clinical study showed that the total amount of analgesic for patient-controlled anesthesia was markedly decreased at the end of the operation and at 8 hours postoperatively in group II compared with group I. CONCLUSIONS: The SSNB and ANB were considered to provide safe and effective analgesia in terms of early postoperative pain in arthroscopic shoulder surgery.


Subject(s)
Arthroscopy , Brachial Plexus/anatomy & histology , Nerve Block/methods , Shoulder Joint/innervation , Shoulder Joint/surgery , Aged , Aged, 80 and over , Analgesia, Patient-Controlled , Axilla/innervation , Cadaver , Female , Humans , Male , Middle Aged , Pain Measurement , Pain, Postoperative/prevention & control , Scapula/innervation
14.
NeuroRehabilitation ; 28(3): 183-97, 2011.
Article in English | MEDLINE | ID: mdl-21558625

ABSTRACT

Computers, telephones, and assistive technology hold promise for increasing the independence, productivity, and participation of individuals with disabilities in academic, employment, recreation, and other activities. However, to reach this goal, technology must be accessible to, available to, and usable by everyone. The authors of this article share computer and telephone access challenges faced by individuals with neurological and other impairments, assistive technology solutions, issues that impact product adoption and use, needs for new technologies, and recommendations for practitioners and researchers. They highlight the stories of three individuals with neurological/mobility impairments, the technology they have found useful to them, and their recommendations for future product development.


Subject(s)
Cell Phone , Computers , Disabled Persons/rehabilitation , Movement Disorders/rehabilitation , Self-Help Devices , Adult , Cerebral Palsy/rehabilitation , Female , Humans , Male , Middle Aged , Muscular Dystrophies/rehabilitation , Paralysis/etiology , Paralysis/rehabilitation , Spinal Cord Injuries/complications , Students , Young Adult
15.
Can J Anaesth ; 58(5): 443-50, 2011 May.
Article in English | MEDLINE | ID: mdl-21369774

ABSTRACT

PURPOSE: We recently showed that the quaternary lidocaine derivative, QX-314, produces long-lasting local anesthesia with a slow onset in animal models in vivo. As quaternary agents do not rapidly penetrate biological membranes or the blood-brain barrier, QX-314 may represent a local anesthetic with decreased systemic toxicity compared with conventional tertiary aminoamines. To test this hypothesis, we conducted an in vivo animal study in mice to compare QX-314 with lidocaine in terms of its relative central nervous system (CNS) and cardiac toxicity. METHODS: With approval from the institutional Animal Care Committee, we used the "up-and-down" method to determine the relative potencies (ED(50)) of lidocaine and QX-314 for CNS and cardiac toxicity in adult CD-1 mice (weight, 20 to 35 g). The animals were administered either intravenous lidocaine or QX-314 (dose range, 7.5 to 30 mg·kg(-1)) and were observed for signs of CNS toxicity (convulsions, ataxia, loss of righting reflex, and/or death). We also observed animals for electrocardiographic evidence of toxic effects on cardiac automaticity, conductivity, and rhythmicity. RESULTS: The ED(50) of lidocaine for CNS toxicity as determined by the "up-and-down" method was 19.5 mg·kg(-1) (95% confidence interval [CI], 17.7 to 21.3 mg·kg(-1); n = 6) compared with 10.7 mg·kg(-1) for QX-314 (95% CI, 9.1 to 12.3 mg·kg(-1); n = 6) (potency ratio, 1.8). Similarly, the ED(50) of lidocaine for electrocardiographic evidence of cardiac toxicity was significantly higher than that of QX-314 (ED(50) of lidocaine, 21.2 mg·kg(-1); 95% CI, 19.0 to 23.4 mg·kg(-1); n = 6 vs ED(50) of QX-314, 10.6 mg·kg(-1); 95% CI, 8.4 to 12.8 mg·kg(-1); n = 6) (potency ratio, 2.0). CONCLUSIONS: In this in vivo animal study, the relative potencies of QX-314 for systemic CNS and cardiac toxicity were significantly higher than those of lidocaine. These data do not support the hypothesis that QX-314 is a safer local anesthetic compared with lidocaine in terms of systemic toxicity. Whereas our results do not exclude the possibility that QX-314 may represent a clinically useful agent to produce long-lasting local anesthesia and nociceptive blockade after a single shot in humans, its systemic toxicity relative to conventional tertiary aminoamide local anesthetics and the underlying mechanisms warrant further study.


Subject(s)
Anesthetics, Local/toxicity , Central Nervous System Diseases/chemically induced , Heart Diseases/chemically induced , Lidocaine/analogs & derivatives , Anesthetics, Local/administration & dosage , Animals , Central Nervous System Diseases/physiopathology , Dose-Response Relationship, Drug , Electrocardiography , Heart Diseases/physiopathology , Injections, Intravenous , Lidocaine/administration & dosage , Lidocaine/toxicity , Mice
17.
Anesthesiology ; 113(2): 438-44, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20613478

ABSTRACT

BACKGROUND: We recently found that peripheral administration of the quaternary lidocaine derivative, QX-314, produces long-lasting sensory and motor blockade in animals. The goal of this study was to test whether intrathecal QX-314 has similar properties. METHODS: We conducted a randomized, double-controlled, blinded study with female CD-1 mice. Animals in the treatment group received lumbar intrathecal QX-314 (0.5-10 mM; volume, 2 microl; each concentration, n = 6). Normal saline and lidocaine (70 mM) served as negative and positive controls (each group, n = 12), respectively. Animals were tested for up to 3 h for lumbosacral neural blockade and observed for adverse effects. RESULTS: No animal injected with saline and 11 of 12 (92%) animals injected with lidocaine displayed reversible lumbosacral motor blockade (P < 0.001). QX-314 (5 mM) produced motor blockade in four of the six (67%) and sensory blockade in five of the six animals (83%; P < 0.05 vs. saline). However, six of the six mice (100%) at 5 mM QX-314 and five of the six (83%) at 10 mM exhibited marked irritation; one of the six animals at 5 mM (17%) and two of the six at 10 mM (33%) died. We observed no neural blockade without adverse effects in any animal injected with QX-314. All animals injected with saline and 11 of the 12 (92%) animals injected with lidocaine demonstrated normal behavior. CONCLUSION: Lumbar intrathecal QX-314 concentration-dependently produced irritation and death in mice, at lower concentrations than those associated with robust motor blockade. Although QX-314 did produce long-lasting neural blockade, these findings indicate that QX-314 is unlikely to be a suitable candidate for spinal anesthesia in humans.


Subject(s)
Akathisia, Drug-Induced/mortality , Lidocaine/analogs & derivatives , Lidocaine/administration & dosage , Pruritus/chemically induced , Pruritus/mortality , Akathisia, Drug-Induced/diagnosis , Animals , Dose-Response Relationship, Drug , Double-Blind Method , Female , Injections, Spinal , Lidocaine/toxicity , Lumbosacral Region , Mice , Pruritus/diagnosis , Random Allocation
18.
Korean J Anesthesiol ; 57(3): 364-366, 2009 Sep.
Article in English | MEDLINE | ID: mdl-30625888

ABSTRACT

Cauda equina syndrome is a well-known but rare complication of spinal anesthesia. An 80-year-old man was scheduled for both herniorrhaphy. Spinal anesthesia was performed at the L3-4 interspinous space with 0.5% hyperbaric bupivacaine 12 mg. Eight hours after anesthesia, the patient complained bilateral sensorimotor deficits of the lower extremities and peroneal region. Urinary and fecal incontinence were also observed. MRI and myelography showed severe central spinal stenosis at L3-4 and L4-5. EMG showed cauda equina syndrome. Seven weeks after the procedure, left decompressive subtotal laminectomy L2-L5 was done. The patient still complains the neuropathic pain in the both lower extremities and ambulates using a walker. The local anesthetic was injected into thecal sac between maximum stenoses, and it is likely that there was poor upward spread leading to maldistribution of local anesthetic and resultant local anesthetic toxicity.

19.
Korean J Anesthesiol ; 57(4): 444-449, 2009 Oct.
Article in English | MEDLINE | ID: mdl-30625904

ABSTRACT

BACKGROUND: A priming dose of rocuronium can shorten the onset time of neuromuscular blockade. The purpose of this study was to evaluate the effect of priming with rocuronium on the onset time and intubation conditions during tracheal intubation with low-dose rocuronium (0.35 mg/kg) and to compare results with those for rocuronium 0.45 mg/kg. METHODS: One hundred twenty four patients were randomly allocated to three groups. Following induction of anesthesia, groups I and III received normal saline while group II received a priming dose of rocuronium (0.05 mg/kg). Three minutes after priming, groups I, II and III received, respectively, 0.45 mg/kg, 0.3 mg/kg and 0.35 mg/kg rocuronium. Intubation was performed 2 minutes after the administration of an intubating dose and intubation conditions were evaluated. Neuromuscular blockade was assessed by accelerography. RESULTS: The proportion of cases having optimal intubation conditions in group I was higher than in groups II and III. There was no significant difference in the onset times among groups. Neuromuscular blockade at 60, 90 and 120 seconds after an intubating dose was similar among all groups except at 60 sec. Maximal blockade for group I was deep compared to groups II and III. CONCLUSIONS: Rocuronium 0.35 mg/kg does not provide satisfactory intubation conditions. There are no effects on onset time and intubation conditions due to priming during tracheal intubation with rocuronium 0.35 mg/kg.

20.
Opt Express ; 16(9): 6260-6, 2008 Apr 28.
Article in English | MEDLINE | ID: mdl-18545329

ABSTRACT

We propose a multiple star wavelength division multiplexing-passive optical network (WDM-PON) to serve several subscriber groups located at a widely distributed area. The architecture based on a band splitting WDM (BSWDM) filter separates upstream and downstream bands to several sub-bands and assign them to different subscriber groups. As a result, it enables to use a single type AWG for second stage splitting points. Thus, it provides color-free outside plant and simplifies management issues. The proposed architecture also provides pay as you grow feature.


Subject(s)
Optics and Photonics , Spectrum Analysis
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