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The Ulleung Basin of the East Sea is a biological hotspot, but studies on the macrobenthos therein are lacking. To evaluate the macrobenthos species diversity and community structure in the Ulleung Basin, we conducted a survey from 2017 to 2021. A total of 262 species of macrobenthos was detected by the survey, and the average habitat density was 243 individuals/m2. The average biomass of macrobenthos was 43.7 g/m2, and the average Shannon and Wiener’s diversity index was 2.3 (0.69–3.61). The dominant species were the polychaetes Terebellides horikoshii, Chaetozone setosa, Scalibregma inflatum, and Aglaophamus sp. and the bivalvia Axinopsida subquadrata. The community structure of macrobenthos differed according to water depth, and a correlation analysis using environmental variables showed that the community was affected by water temperature, salinity, and dissolved oxygen. The macrobenthic fauna in the Ulleung Basin was greatly influenced by water depth, the sedimentary environment was different, and the dominant species were also different. In addition, there was little seasonal change compared to the East Sea coast. Our findings will facilitate further investigation of benthic ecosystems throughout the East Sea.

This study investigated the effect of an excess and a deficit of spinal 5-hydroxytryptamine (5-HT) on the mechanical allodynia and neuroglia activation in a rodent pain model of carrageenan inflammation.Male Sprague-Dawley rats were implanted with an intrathecal (i.t.) catheter to administer the drug. To induce an excess or deficit of 5-HT in the spinal cord, animals were given either three i.t. 5-HT injections at 24-hour intervals or a single i.t. injection of 5,7-dihydroxytryptamine (5,7-DHT) before carrageenan inflammation. Mechanical allodynia was measured using the von Frey test for 0-4 hours (early phase) and 24-28 hours (late phase) after carrageenan injection. The changes in the activation of microglia and astrocyte were examined using immunofluorescence of the dorsal horn of the lumbar spinal cord.Both an excess and a deficit of spinal 5-HT had no or a minimal effect on the intensity of mechanical allodynia during the early phase but prevented the attenuation of mechanical allodynia during the late phase, which was observed in animals not treated with i.t. 5-HT or 5,7-DHT. Animals with an excess or deficit of 5-HT showed stronger activation of microglia, but not astrocyte, during the early and late phases, than did normal animals.Imbalance in the descending 5-HT pathway in the spinal cord could aggravate the mechanical allodynia and enhance the activation of microglia, suggesting that the spinal 5-HT pathway plays an essential role in maintaining the nociceptive processing in balance between facilitation and inhibition in inflammatory pain caused by carrageenan inflammation.

Background: Chemotherapy-induced peripheral neuropathy (CIPN) is a major reason for stopping or changing anticancer therapy. Among the proposed pathomecha-nisms underlying CIPN, proinflammatory processes have attracted increasing attention. Here we assessed the role of prostaglandin D2 (PGD2) signaling in cisplatininduced neuropathic pain. Methods: CIPN was induced by intraperitoneal administration of cisplatin 2 mg/kg for 4 consecutive days using adult male Sprague-Dawley rats. PGD2 receptor DP1 and/or DP2 antagonists were administered intrathecally and the paw withdrawal thresholds were measured using von Frey filaments. Spinal expression of DP1, DP2, hematopoietic PGD synthase (H-PGDS), and lipocalin PGD synthase (L-PGDS) proteins were analyzed by western blotting. Results: The DP1 and DP2 antagonist AMG 853 and the selective DP2 antagonist CAY10471, but not the DP1 antagonist MK0524, significantly increased the paw withdrawal threshold compared to vehicle controls (P = 0.004 and P < 0.001, respectively). Western blotting analyses revealed comparable protein expression levels in DP1 and DP2 in the spinal cord. In the CIPN group the protein expression level of L-PGDS, but not of H-PGDS, was significantly increased compared to the control group (P < 0.001). Conclusions: The findings presented here indicate that enhanced PGD2 signaling, via upregulation of L-PGDS in the spinal cord, contributes to mechanical allodynia via DP2 receptors in a cisplatin-induced neuropathic pain model in rats, and that a blockade of DP2 receptor activation may present a novel therapeutic target for managing CIPN.

Background There is still unmet need in treating neuropathic pain and increasing awareness regarding the use of drug combinations to increase the effectiveness of treatment and reduce adverse effects in patients with neuropathic pain. Methods This study was performed to determine the individual and combined effects of pregabalin, tianeptine, and clopidogrel in a rat model of neuropathic pain. The model was created by ligation of the L5-L6 spinal nerve in male Sprague–Dawley rats; mechanical allodynia was confirmed using von Frey filaments. Drugs were administered to the intrathecal space and mechanical allodynia was assessed; drug interactions were estimated by isobolographic or fixed-dose analyses. Results Intrathecal pregabalin and tianeptine increased the mechanical withdrawal threshold in a dose-dependent manner, but intrathecal clopidogrel had little effect on the mechanical withdrawal threshold. An additive effect was noted between pregabalin and tianeptine, but not between pregabalin and clopidogrel. Conclusions These findings suggest that intrathecal coadministration of pregabalin and tianeptine effectively attenuated mechanical allodynia in the rat model of neuropathic pain. Thus, pregabalin plus tianeptine may be a valid option to enhance the efficacy of neuropathic pain treatment.

Background Despite various strategies designed for preventing pain from propofol injection, it is still common and distressing to the patients. The purpose of the present study was to investigate the adequate effect-site concentration (Ce) of remifentanil to prevent pain due to propofol injection. Methods A total of 160 adults scheduled for elective surgery were randomly assigned to one of four groups receiving normal saline (group S) or remifentanil at a Ce of 2 (group R2), 3 (group R3), or 4 ng/ml (group R4), administered via target-controlled infusion, followed by the injection of 2 mg/kg of propofol (delivered with 1% lipid propofol). The severity and incidence of injection pain were assessed on a four-point scale. Results The incidence of propofol injection pain was significantly lower in group R2, R3, or R4 than in group S (30%, 5%, or 2.5% vs. 70%, respectively). Moreover, the intensity of the pain was lesser in group R2, R3, or R4 than in group S. However, the incidence or severity of injection was not different between groups R3 and R4. Conclusions During the induction of balanced anesthesia using propofol injection, pretreatment with remifentanil at a target Ce of 3 ng/ml effectively reduced propofol injection pain in adults.

Background: Supraspinal delivery of neurotensin (NTS), which may contribute to the effect of a systemically administered agonist, has been reported to be either pronociceptive or antinociceptive. Here, we evaluated the effects of systemically administered NTSR1 agonist in a rat model of neuropathic pain and elucidated the underlying supraspinal mechanism. Methods: Neuropathic pain was induced by L5 and L6 spinal nerve ligation in male Sprague-Dawley rats. The effects of intraperitoneally administered NTSR1 agonist PD 149163 was assessed using von Frey filaments. To examine the role of 5-HT neurotransmission, a serotonin (5-HT) receptor antagonist dihydroergocristine was pretreated intrathecally, and spinal microdialysis studies were performed to measure the change in extracellular level of 5-HT in response to PD 149163 administration. To investigate the supraspinal mechanism, NTSR1 antagonist 48692 was microinjected into the rostral ventromedial medulla (RVM) prior to systemic PD 149163. Additionally, the effect of intrathecal DHE on intra-RVM PD 149163 was assessed. Results: Intraperitoneally administered PD 149163 exhibited a dose-dependent attenuation of mechanical allodynia. This effect was partially reversed by intrathecal pretreatment with dihydroergocristine and was accompanied by an increased extracellular level of 5-HT in the spinal cord. The PD 149163-produced antinociception was also blocked by intra-RVM SB 48692. Direct injection of PD 149163 into the RVM mimicked the maximum effect of the same drug delivered intraperitoneally, which was reversed by intrathecal dihydroergocristine. Conclusions: These observations indicate that systemically administered NTSR1 agonist produces antinociception through the NTSR1 in the RVM, activating descending serotonergic projection to release 5-HT into the spinal dorsal horn.

The present study investigated the effects of intrathecal nefopam on the pain behavior and on the extracellular levels of serotonin (5-HT), norepinephrine (NE), and glutamate in the spinal cord, in a rat model of pain induced by formalin. Nefopam was intrathecally administered 10 min prior to the formalin test to assess its antinociceptive effects. In another cohorts of animals, dihydroergocristine, yohimbine, or (RS)-α-Methylserine-O-phosphate (MSOP), a serotonergic, α-2 adrenergic receptor, or group III metabotropic glutamate receptor antagonist, respectively, were administered prior to the application of nefopam in the formalin test. Microdialysis studies were conducted to measure the extracellular levels of 5-HT, NE, and glutamate in the spinal cord following nefopam administration. Intrathecal nefopam reduced formalin-induced behavior in both phases of the test. The blockade of serotonergic or adrenergic receptors partially reversed the analgesic effects of nefopam in the first phase of the formalin test whereas MSOP reversed these effects in both phases. The microdialysis results revealed that intrathecal nefopam significantly increased 5-HT and NE levels and attenuated the formalin-induced release of glutamate in the spinal cord. Thus, the present data suggest that the increase in the extracellular levels of 5-HT and NE, and reductions in glutamate release in the spinal cord, may have contributed to the analgesic effects of nefopam.

Macrofauna in the Clarion-Clipperton Fracture Zone remain poorly understood, due both to gross undersampling and to the fact that most species collected from the area are new to science. Evaluation of the diversity and species distribution of the benthic fauna in this area is critical to predicting and managing the impacts of manganese nodule mining. In this study, we investigated the distribution of macrofauna to understand the natural variability in the macrobenthic community and, by extension, to establish a baseline for environmental risk assessment. Samples were collected from the KR5 block of the Korea Contract Area, within the abyssal area of the Clarion-Clipperton Fracture Zone in the northeastern Pacific Ocean, by the RV Onnuri from 2012–2014. A total of 36 core samples were examined in the survey, from which we identified 183 macrobenthic species in 25 faunal groups with a mean density of 257 ind/m2. Not taking into account meio-faunal groups such as nematodes and harpacticoid copepods, the highest percentage of individuals was represented by Arthropoda. The dominant species (> 1% of total density) were the tanaids Typhlotanais sp.1, and Akanthophoreus spp. and Stenotanais sp., the isopod Macrostylis sp.1, and the polychaetes Cirratulidae spp. and Levinsenia uncinata. The abundances of the two dominant species, the tanaid Typhlotanais sp1. and isopod Macrostylis sp.1., were positively correlated with total organic carbon (TOC). There were no differences in macrofaunal density and community structure between preserved areas (PRA), the potential benthic impacted site (BIS), and other areas near the BIS. In general, higher diversity was associated with homogeneous environmental conditions, with high nodule coverage (> 50%) and TOC.

The movement of animals and materials among habitats can affect community structure. Subtidal rocky reefs are important in the productivity, food web, recruitment, and behavior of benthic animal communities and fish. We investigated how rocky reefs influence the composition and abundance of benthic species in the East Sea of Korea. In total, 157 species of macrobenthic fauna were collected, of which 56 were polychaetes, 49 were crustaceans, and 33 were mollusks. Polychaetes constituted the dominant taxon and accounted for 55% of the average density of the macrobenthos. The sediment around the rocky reef comprised mainly coarse-grained particles, and was dominated by suspension-feeding polychaetes. Cluster analysis divided the macrobenthic community into three groups, which were correlated with the distribution of polychaete species. The canonical correspondence analysis showed that sediment composition is an important variable in polychaete distribution patterns. This study suggests that polychaetes are a representative taxon around subtidal rocky reefs, and changes in sediment type is a key factor influencing the characteristics of polychaete communities.

This study analyzed the community structure of macrobenthic organisms in the subtidal area suffering under the influence of thermal discharge from the Uljin nuclear power plant during 2012-2013 and reviewed the temporal change in the faunal composition of the macrobenthic community using data from p...

Rationale: Seizures are rare during the perioperative period; in most cases, there is a previous history of epilepsy or surgery-associated seizures. Febrile convulsions may occur when the body temperature rises above 38°C; this is the most common cause of seizures in children. Febrile convulsions after general anesthesia in the postanesthetic care unit (PACU) without a past or family history are rare. Some reviews suggest that since anesthesia changes immunity, elective surgery should be postponed three weeks after live vaccination. Patient: A 12-month-old female with bilateral hearing loss underwent cochlear implantation under general anesthesia. She did not have any history of convulsions or developmental disorders. However, 1 week before surgery, measles-mumps-rubella (MMR) vaccination was given as a regular immunization. Diagnoses: Forty minutes after arrival at the PACU, sudden generalized tonic-clonic movement occurred during recovery and the patient's measured body temperature exceeded 38.0°C. Interventions: Thiopental sodium was administered intravenously as an anticonvulsant, and the tonic-clonic movement stopped immediately. Endotracheal intubation was performed to secure the airway, and tepid massage and diclofenac β-dimethylaminoethanol administration were performed to lower the patient's body temperature. Outcomes: There was no further fever and no seizures, and no other neurological deficits were observed until discharge. Lessons: The anesthesiologist should check the recent vaccination history even if the patient has not developed particular symptoms after vaccination. It is important to know that febrile convulsions may occur in patients who have recently received MMR vaccination.

Background: This study was undertaken to determine the effect-site concentration of remifentanil for blunting hemodynamic responses to double lumen endobronchial intubation during target controlled infusion (TCI)-total intravenous anesthesia (TIVA) using 4.0 μg/ml of propofol with remifentanil. Methods: Sixty patients (American society of anesthesiologists physical status classification 1 or 2) were randomly allocated according to the target effect-site concentration of remifentanil (R3.0: remifentanil 3.0 ng/ml; R3.5: remifentanil 3.5 ng/ml; R4.0: remifentanil 4.0 ng/ml). The effect-site concentration of propofol at loss of consciousness was recorded. Mean arterial pressure (MAP), heart rate (HR) and bispectral index (BIS) were recorded at just before remifentanil administration (baseline), at the time of target effect site concentration of remifentanil and propofol, at just before intubation and 1, 2, 3 min after intubation. Results: MAP was significantly increased compared with baseline at 1, 2 min after intubation in R3.0, but was significantly decreased in R4.0. MAP of R3.5 was not different from the baseline after intubation. HR was significantly decreased compared with baseline at the time of target effect site concentration of propofol and immediate before intubation in R3.5 and R4.0. After intubation, HR was significantly increased compared with baseline at only 1 min after intubation and returned to the baseline in R3.0. However, HR was continuously decreased in R4.0. Conclusions: These findings suggest that effective target effect-site concentration of remifentanil for blunting hemodynamic responses to double lumen endotracheal intubation was 3.5 ng/ml during TCI-TIVA using 4.0 μg/ml of propofol with remifentanil. (Korean J Anesthesiol 2009; 57: 8~12)

Controlling extracellular glutamate level in a physiological range is important to maintain normal sensory transmission. Here, we investigated the paradoxical action of glutamate transporters in the rat formalin test to elucidate a possible role of inversely operating transporters in its analgesic mechanism. The effects of glutamate transporter inhibitor on formalin-induced pain behavior were examined. Then we performed a microdialysis study to clarify the differential change in extracellular glutamate concentration by intrathecal administration of transportable and non-transportable blockers. And we further investigated the mechanism pharmacologically via pretreatment with antagonists of various receptors and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) staining. Intrathecally-injected glutamate transporter inhibitors, non-transportable DL-threo-β-benzyloxyaspartat (TBOA) and transportable trans-pyrrolidine-2,4-dicarboxylic acid (t-PDC), produced paradoxical antinociception in the formalin test. In normal rats, inhibition of the glutamate transporter increased extracellular glutamate. In the formalin model rats, TBOA suppressed while t-PDC enhanced glutamate release. When tPDC was pretreated 30min prior to formalin injection, glutamate release was blocked. Blocking α-2 adrenergic receptors reversed the tPDC analgesia. Increased apoptosis was not apparent in the spinal dorsal horn of tPDC-treated rats compared to the control group. These data suggest that glutamate transporters in a formalin-induced pain state work in a reverse mode and can be blocked from releasing glutamate by TBOA and preloaded tPDC. The analgesic mechanism of TBOA may be related to the blockade of inversely operating transporter, and that of tPDC may be associated with the activation of noradrenergic neurotransmission but not with dorsal horn neurotoxicity.

We validate the analgesic efficacy of tianeptine by different administration routes and timing in a rat model of neuropathic pain. Neuropathic pain was induced by ligating the L5 and L6 spinal nerves in male Sprague-Dawley rats, and mechanical allodynia was assessed using von Frey filaments. The effects of orally administered tianeptine and pretreatment with tianeptine (intrathecally or intraperitoneally) on mechanical allodynia were assessed. Oral and preemptive intrathecal administration of tianeptine significantly increased the paw withdrawal threshold but preemptive intraperitoneal administration did not. Nevertheless, intraperitoneal pretreatment of tianeptine potentiated the antiallodynic effects of subsequently administered tianeptine. These findings suggest that tianeptine may be effective for preventing and treating neuropathic pain and that it can be used more widely in clinical pain practice.

BACKGROUND Nefopam has been known as an inhibitor of the reuptake of monoamines, and the noradrenergic and/or serotonergic system has been focused on as a mechanism of its analgesic action. Here we investigated the role of the spinal dopaminergic neurotransmission in the antinociceptive effect of nefopam administered intravenously or intrathecally. METHODS The effects of intravenously and intrathecally administered nefopam were examined using the rat formalin test. Then we performed a microdialysis study to confirm the change of extracellular dopamine concentration in the spinal dorsal horn by nefopam. To determine whether the changes of dopamine level are associated with the nefopam analgesia, its mechanism was investigated pharmacologically via pretreatment with sulpiride, a dopaminergic D2 receptor antagonist. RESULTS When nefopam was administered intravenously the flinching responses in phase I of the formalin test were decreased, but not those in phase II of the formalin test were decreased. Intrathecally injected nefopam reduced the flinching responses in both phases of the formalin test in a dose dependent manner. Microdialysis study revealed a significant increase of the level of dopamine in the spinal cord by intrathecally administered nefopam (about 3.8 fold the baseline value) but not by that administered intravenously. The analgesic effects of intrathecally injected nefopam were not affected by pretreatment with sulpiride, and neither were those of the intravenous nefopam. CONCLUSIONS Both the intravenously and intrathecally administered nefopam effectively relieved inflammatory pain in rats. Nefopam may act as an inhibitor of dopamine reuptake when delivered into the spinal cord. However, the analgesic mechanism of nefopam may not involve the dopaminergic transmission at the spinal level.

This study examined the relationship between macrobenthic distribution patterns and environmental factors in salt marsh vegetation in Donggeomdo, Ganghwa on the west coast of Korea. Nine stations were fixed on a transect across the salt marsh vegetation, and field sampling was carried out monthly from July 1997 to June 1998. A total of 38 species of macrobenthos were recorded: each of faunal groups, 13 (34.2%) Arthropoda, 12 (31.6%) Polychaeta, 8 (21.1%) Mollusca, and 5 (13.2%) others. The mean density was 2,659 individuals/㎡, with a mean biomass of 178.6 gWWt/㎡. Mollusca dominated in terms of abundance and biomass, with a mean density of 2,172 individuals/㎡ (81.7%) and a mean biomass of 131.9 gWWt/㎡ (73.9%). The number of species decreased in winter (January−February), while mean density increased in the spring (May−June). The biomass was relatively in Summer and Fall (July−November), than any other season. The number of species was high in pure stands of Suaeda japonica in the lower salt marsh vegetation, and the mean density and biomass were high in mixed halophyte communities in the middle salt marsh vegetation. Two Mollusca, the bivalve Glauconome chinensis and gastropod Assiminea lutea, were dominant. The densities of these two species were high in mixed halophyte communities in the middle salt marsh vegetation. Non-metric multi-dimensional scaling (nMDS) showed that the study area could be divided into four groups corresponding to the vertical distribution of tidal levels and halophytes. Spearman’s rank correlation revealed that the distribution patterns and community structure of macrobenthos were related to environment variables such as salinity of the substrates, exposure time, and grain size compositions of the sediment in the salt marsh vegetation. Particularly, the distribution and density of some dominant species showed differences along the vertical distributions of halophytes.

We investigated the biological impact of extensive Manila clam (Ruditapes philippinarum) aquaculture on macrobenthic communities in a tidal ecosystem in Korea. We collected macrobenthos (&gt, 1 mm in length) samples seasonally in the intertidal zone in Geunsoman, Taean, Korea from April 2011 to December 2014. We identified 146 macrobenthos species, including 60 polychaetes, 53 crustaceans, and 16 mollusks. A biota&ndash, environment matching (BIO&ndash, ENV) analysis indicated that the benthic community was affected by mean sediment grain size (Mz), total organic carbon (TOC), and R. philippinarum biomass. We found no correlation between R. philippinarum and the main dominant species (Heteromastus filiformis, Ceratonereis erythraeensis, and Ampharete arctica), which have a different feeding strategy, thus, this may result in a lack of competition for food resources. In addition, we found that flourishing R. philippinarum positively affects the macrobenthos density but negatively affects the biodiversity index. Moreover, competition between species does not occur clearly, and environmental variables (sediment, organic carbon) are important.

Macrophage-inducible C-type lectin (Mincle), a pattern recognition receptor, is a critical component of the innate immune system that is involved in the pathogenesis of chronic pain. Previous studies have reported the expression of Mincle in neuronal and glial cells of the brain, but its expression and role in pain processing at the spinal level remain to be determined. The current study was performed to identify Mincle in the spinal cord and to investigate the effect of Mincle activation on spinal sensitization. Most Mincle immunoreactivity was localized within the grey matter and the dorsal and ventral horns of the lumbar spinal cord in naive rats. A single intrathecal (i.t.) injection of trehalose-6,6-dibehenate (TDB), a Mincle ligand, induced mechanical allodynia. Immunoreactivity to Mincle and Iba-1 in the spinal cord significantly increased after i.t. injection of TDB. Mechanical allodynia was attenuated by daily i.t. injection of minocycline. However, double immunofluorescence revealed that Mincle co-localizes with NeuN (neurons), but not with Iba-1 (microglia) or GFAP (astrocytes). In conclusion, we found that Mincle was present in spinal cord neurons, but not microglia or astrocytes, and may play a role in microglia-induced spinal sensitization.

The loss of imprinting of MEST has been linked to certain types of cancer by promoter switching. However, MEST-mediated regulation of tumorigenicity and metastasis are yet to be understood. Herein, we reported that MEST is a key regulator of IL-6/JAK/STAT3/Twist-1 signal pathway-mediated tumor metastasis. Enhanced MEST expression is significantly associated with pathogenesis of breast cancer patients. Also, MEST induces metastatic potential of breast cancer through induction of the EMT-TFs-mediated EMT program. Moreover, MEST leads to Twist-1 induction by STAT3 activation and subsequently enables the induction of activation of the EMT program via the induction of STAT3 nuclear translocation. Furthermore, the c-terminal region of MEST was essential for STAT3 activation via the induction of JAK2/STAT3 complex formation. Finally, MEST significantly increases the breast cancer’s ability to metastasize from the mammary gland to the lung. These observations suggest that MEST is a promising target for intervention to prevent tumor metastasis.

This study examined the effects of intrathecal areca nut on spinal nerve-ligated and chemotherapy-induced neuropathic pain (NP), and investigated the relevance of spinal 5-hydroxytryptamine (5-HT) and α2-adrenergic receptors to those effects. For drug administration, intrathecal catheters were inserted into the subarachnoid space of male Sprague-Dawley rats. NP was induced either by spinal nerve ligation (left spinal nerves L5 and L6) or by chemotherapeutic injection (intraperitoneal cisplatin, 2 mg/kg/day, once daily for 4 days). Paw withdrawal thresholds (PWT) were mechanically assessed using von Frey filaments. The involvement of 5-HT and α2-adrenergic receptors in antiallodynia was determined using antagonists with the following receptor specificities: nonselective 5-HT (dihydroergocristine), 5-HT7 (SB269970), nonselective α2-adrenoceptor (yohimbine), α-2A (BRL 44408), α-2B (ARC 239), and α-2C (JP 1302). Intrathecal areca nut significantly increased the PWT in both spinal nerve-ligated and chemotherapy-induced NP (‡ p < 0.001). Intrathecal dihydroergocristine, SB269970, yohimbine, BRL 44408, ARC 239, and JP 1302 significantly reversed the antiallodynic effects of areca nut in both NP states (‡ p < 0.001). Collectively, intrathecal areca nut suppressed mechanical allodynia induced by spinal nerve ligation and cisplatin injection. Furthermore, spinal 5-HT7 receptor and α2A, α2B, and α2C-adrenoceptors contributed to the antiallodynic effects of areca nut.

Background: Although the inhibitory role of the 5-hydroxytrypatmine receptor 7(5-HT7R) on nociceptive processing is generally recognized, an excitatory effect associated with a reduced 5-HT7R expression has also been observed in the nerve injury model. In the carrageenan model, no significant effect is produced by the 5-HT7R activation, but the change in 5-HT7R expression has not been examined. Lesioning of the spinal serotonergic pathway enhances allodynia in the carrageenan model, but it also relieves several other pain states, including in the formalin model. While lesioning suppresses the activation of the extracellular signal-regulated kinase (ERK) of the spinal cord in the formalin model, its role in the carrageenan model has not been reported. Methods: Following intraplantar injections of carrageenan, the spinal 5-HT7R expression was examined using Western blotting in male Sprague-Dawley rats. The effect of serotonergic pathway lesioning with intrathecal 5,7-dihydroxytryptamine (5,7-DHT) on the expression of the phospho-ERK was measured. Results: The expression of the 5-HT7R in the carrageenan model was not significantly different from that of naive animals. The expression of the spinal p-ERK in the carrageenan model was significantly increased, but returned to the level of a naive rat 1 hour after the carrageenan injection. However, it remained significantly higher 1 hour after the injection in the animals treated with 5,7-DHT than in the naive and control rats. Conclusions: The expression of the spinal 5-HT7R is not altered by peripheral inflammation with carrageenan, suggesting that the lack of antinociceptive effect of the 5-HT7R activation is partly attributable to the absence of changes in the expression of the 5-HT7R in the spinal cord. The extended increase of the spinal p-ERK might be related to the enhanced pain behavior in the animals with lesions of the spinal serotonergic pathway in the carrageenan model.

Background: The aims of this study were to compare the efficacy of sevoflurane inhalation alone, intravenous remifentanil alone, and the combination of sevoflurane inhalation and remifentanil as pretreatment for the prevention of rocuronium-induced withdrawal movement in pediatric patients. Methods: In this prospective, randomized study, 90 American Society of Anesthesiologists physical status I or II pediatric patients aged 3 to 10 years were randomly allocated to one of three treatment groups: The Group S comprising the patients receiving sevoflurane inhalation, the Group R comprising those doing intravenous remifentanil 0.5 μg/kg and the Group C comprising those doing sevoflurane inhalation+intravenous remifentanil 0.5 μg/kg. The response of the patients was graded based on a 4-point scale. Results: The overall incidence of withdrawal movement on rocuronium injection was 54% (16/30) in the Group S, 57% (17/30) in the Group R and 17% (5/30) in the Group C. There was no significant difference in the incidence of with drawal movements on rocuronium injection between the Group S and Group R. In addition, the incidence of withdrawal movements and generalized movement on rocuronium injection was significantly lower in the Group C as compared with the Group S and R (P < 0.05). Conclusions: Our results indicate not only that there was no significant difference in the degree of the effect in lower ing the incidence of withdrawal movements on rocuronium injection between sevoflurane inhalation and intravenous remifentanil but also that it was significantly higher when combined with intravenous remifentanil as compared with the single use of sevoflurane inhalation or intravenous remifentanil. (Korean J Anesthesiol 2014; 67: 373-377)

Hwang, S.W.; Lee, H.G.; Choi, K.H.; Kim, C.K., and Lee, T.W., 2014. Impact of sand extraction on fish assemblages in Gyeonggi Bay, Korea During 2006 and 2007, 35.0 × 106 m3 of marine sand was extracted by the construction industry from Gyeonggi Bay, which is an area within the coastal waters off the Taean District of Korea. The goal of our study was to compare the catches and assemblage structure of fish in this sand mining area (SMA) with those of two other nonmining areas (NMAs) in the bay. An otter trawl was used to obtain fish samples in each area. Both cluster analysis and nonmetric multidimensional scaling of the species composition in the sampled areas showed a higher similarity between the two NMAs than between the NMAs and the SMA. Furthermore, the SMA had significantly lower species richness (R1), species diversity (H′), and fish abundance compared with the two NMAs. These results could be associated with bottom disturbance related to the mining of seabed sediments. In conclusion, we co...

The purpose of this study was to validate the effects of tianeptine on serotonergic and noradrenergic neurotransmission in a rat model of neuropathic pain. Neuropathic pain was induced by ligating the L5 and L6 spinal nerves in male Sprague-Dawley rats, and mechanical allodynia was assessed using von Frey filaments. The effects of intrathecally administered tianeptine on mechanical allodynia were assessed. Dihydroergocristine or yohimbine, a serotonergic or α-2 adrenergic receptor antagonists, respectively, were intrathecally administered 10min before tianeptine to investigate its mechanism of action. Additionally microdialysis studies were performed to measure the extracellular levels of serotonin (5-HT) and norepinephrine (NE) in the spinal dorsal horn following tianeptine administration. Intrathecal tianeptine significantly increased the paw withdrawal thresholds in a dose-dependent manner and the antiallodynic effect was antagonized by dihydroergocristine and yohimbine. Microdialysis studies revealed that tianeptine increased the levels of 5-HT and NE in the spinal dorsal horn. These findings suggest that tianeptine may be effective for the management of neuropathic pain and that its analgesic mechanism is exerted by increased levels of 5-HT and NE in the synaptic cleft at the spinal level.

Background To manage intractable cancer pain, an alternative to systemic analgesics is neuraxial analgesia. In long-term treatment, intrathecal administration could provide a more satisfactory pain relief with lower doses of analgesics and fewer side-effects than that of epidural administration. However, implantable drug delivery systems using intrathecal pumps in Korea are very expensive. Considering cost-effectiveness, we performed epidural analgesia as an alternative to intrathecal analgesia. Methods We retrospectively investigated the efficacy, side effects, and complications of epidural morphine and local anesthetic administration through epidural catheters connected to a subcutaneous injection port in 29 Korean terminal cancer patients. Patient demographic data, the duration of epidural administration, preoperative numerical pain rating scales (NRS), side effects and complications related to the epidural catheterization and the drugs, and the numerical pain rating scales on the 1st, 3rd, 7th and 30th postoperative days were determined from the medical records. Results The average score for the numerical pain rating scales for the 29 patients decreased from 7 ± 1.0 at baseline to 3.6 ± 1.4 on postoperative day 1 (P < 0.001). A similar decrease in pain intensity was maintained for 30 days (P < 0.001). Nausea and vomiting were the most frequently reported side effects of the epidural analgesia and two patients (6.9%) experienced paresthesia. Conclusions Epidural morphine and local anesthetic infusion with a subcutaneous pump seems to have an acceptable risk-benefit ratio and allows a high degree of autonomy to patients with cancer pain.

Background: Nefopam has shown an analgesic effect on acute pain including postoperative pain. The reuptake of monoamines including serotonin and noradrenaline has been proposed as the mechanism of the analgesic action of nefopam, but it remains unclear. Although alpha-adrenergic agents are being widely used in the perioperative period, the role of noradrenergic modulation in the analgesic effect of nefopam has not been fully addressed. Methods: Changes in the antinociceptive effect of intrathecal (i.t.) nefopam against formalin-elicited flinching responses were explored in Sprague-Dawley rats pretreated with i.t. 6-hydroxydopamine (6-OHDA), which depletes spinal noradrenaline. In addition, antagonism to the effect of nefopam by prazosin and yohimbine was evaluated to further elucidate the antinociceptive mechanism of i.t. nefopam. Results: Pretreatment with i.t. 6-OHDA alone did not alter the flinching responses in either phase of the formalin test, while it attenuated the antinociceptive effect of i.t. nefopam significantly during phase 1, but not phase 2. The antagonist of the alpha-2 receptor, but not the alpha-1 receptor, reduced partially, but significantly, the antinociceptive effect of i.t. nefopam during phase 1, but not during phase 2. Conclusions: This study demonstrates that spinal noradrenergic modulation plays an important role in the antinociceptive effect of i.t. nefopam against formalin-elicited acute initial pain, but not facilitated pain, and this action involves the spinal alpha-2 but not the alpha-1 receptor. (Korean J Pain 2014; 27: 23-29)

In Korea, more than 300 oil spill accidents occur every year. Despite the frequency, only a small pool of data is available on the initial effect of oil spill on macrobenthic fauna inhabiting rocky shores. The aim of this study was to analyze the variation of macrobenthic fauna composition and community structure on rocky shores, and understand the impact of oil on rocky shore organisms after the Hebei Spirit oil spill. Field surveys were carried out in five regions dose to the wreck site in January, April and September 2008. Polluted sites after the Hebei Spirit oil spill showed that biological index consistently decreased for 9 months limited to breeding and recruitment of organisms by spilled oil. Macrobenthic community was subdivided into 3 groups by species elimination and differences between density of major dominant species: enriched biota community under a relatively stable environment, the second with relatively low ecological index and the last with poor community. In this study, species number did not clearly reflect the effect of oil on the rare and mobile species. However, mean density, biomass and community structure showed the effect of oil by considering breeding activity, decline in recruitment and variation pattern with time.

Petroleum hydrocarbon contamination and macrobenthos in the sandy tidal flats of Taean were monitored for 1 year to assess the impacts of Hebei Spirit oil on the macrobenthic community. A total of 207 macrobenthic fauna was collected, and the mean density and biomass of macrobenthic fauna continued to decrease until 12 months after the oil spill, but macrobenthic density at the most heavily affected sites increased by about twofold. In January 2008, the dominant species occurred at very low densities in strongly affected sites. The macrobenthic communities differed between oil-affected and unaffected sites. In particular, differences in community structure at Mallipo beach were larger than those at Shinduri. We suggest that long-term monitoring is needed to assess the specific effects of oil pollution on the sandy intertidal macrobenthic community.

Opioids have been the mainstay analgesics for postoperative, cancerous, and chronic noncancerous pain. Common concerns regarding the use of opioids include the development of physical dependence and addiction. However, as a potential complication of opioid therapy, opioid-induced hyperalgesia (OIH) is often overlooked. That is, patients receiving opioids to control their pain may paradoxically become more sensitive to pain as a consequence of opioid therapy. OIH is a very important issue because it may complicate the clinical course of pain treatment and even worsen the suffering of patients receiving opioids because of the development of excruciating pain. Three OIH types were defined: 1) in the context of maintenance dosing and withdrawal, 2) at very high or escalating doses, and 3) at ultra-low doses. In the literature, most attention has been paid to the first 2 forms, and almost all cases of reported OIH have been ascribed to morphine administration. The third form of OIH has not been documented in humans, although it has been observed in animals. We present 2 cases of OIH resulting from administration of tramadol, which is a synthetic analogue of codeine and exhibits 10-fold less affinity for mu-opioid receptors, in patients suffering from chronic pain. The 2 cases presented herein imply the importance of recognizing OIH in patients medicated with tramadol if analgesic effects are lost in the context of dose titration, when generalized pain is reported without any evidence of disease exacerbation. While OIH associated with ultra-low dose opiates seems to be quite rare, if it is suspected, switching to other drugs and an appropriate treatment should be considered. Key words: Opioid-induced hyperalgesia, opioids, chronic pain, serotonin syndrome, tramadol, ketamine

We compared environmental effects on the macrobenthic community of the Han River Estuary in summer, when freshwater input from the Han River increased, and in spring, when freshwater input decreased. Field samples were taken from the upper region of the Shingok reservoir to the southern area of Ganghwado at 18 sampling sites after rainy (August 2006) and dry (March 2007) seasons. Macrobenthic fauna were collected using a Van Veen Grab (0.025 m2 and 0.1 m2) and environmental factors were measured simultaneously. Dominant species of macrobenthic fauna and the macrobenthic community were divided into two areas, the area of the Han River with no salinity ( 20 psu). The dominant species Byblis japonicus appeared at Junruri in the dry season. The distributions of two polychaetes, Hediste japonica and Nephtys caeca, were divided into the lower and upper areas of the Singok submerged weir. BIO-ENV (the matching of biotic to environmental patterns) analysis revealed that salinity was the most important factor affecting macrobenthic communities in the Han River Estuary, with other factors such as sediment grain size, bottom dissolved oxygen, and total organic carbon of sediment being secondary.

Refractory angina pectoris is defined as angina refractory to optimal medical treatment and standard coronary revascularization procedures. Despite recent therapeutic advances, patients with refractory angina pectoris are not adequately treated. Spinal cord stimulation is a minimally invasive and reversible technique which utilizes electrical neuromodulation by means of an electrode implanted in the epidural space. It has been reported to be an effective and safe treatment for refractory angina pectoris. We report a case of spinal cord stimulation which has effectively relieved chest pain due to coronary artery disease in a 40-year-old man. This is the first report of spinal cord stimulation for treatment of refractory angina pectoris in South Korea.

Epigallocatechin-3-gallate (EGCG), the major catechin in green tea, is known to have antioxidant activity against nitric oxide (NO) by scavenging free radicals, chelating metal ions, and inducing endogenous antioxidant enzymes. NO and NO synthase (NOS) play an important role in nociceptive processing. In this study, we examined the effects of intrathecal EGCG in neuropathic pain induced by spinal nerve ligation and the possible involvement of NO. Intrathecal EGCG attenuated mechanical allodynia in spinal nerve ligated-rats, compared to sham-operated rats, with a maximal possible effect of 69.2%. This antinociceptive effect was reversed by intrathecal pretreatment with l-arginine, a precursor of NO. Intrathecal EGCG also blocked the increase in nNOS expression in the spinal cord of spinal nerve-ligated rats, but iNOS expression was not significantly suppressed. These findings suggest that intrathecal EGCG could produce an antiallodynic effect against spinal nerve ligation-induced neuropathic pain, mediated by blockade of nNOS protein expression and inhibition of the pronociceptive effects of NO.