Miastenia gravis: Registro de 190 casos en un centro único / Myasthenia gravis. Register of 190 cases in a single center

La miastenia gravis (MG) es una enfermedad autoinmune mediada por anticuerpos dirigidos contra proteínas post sinápticas de la unión neuromuscular. El objetivo de este estudio fue describir los aspectos clínicos, epidemiológicos y serológicos de pacientes con MG en un Hospital Público de la Ciudad de Buenos Aires. Se realizó un análisis retrospectivo sobre 190 enfermos con diagnóstico de MG. La edad media de inicio de la enfermedad fue de 38 años; 57 (30%) fueron MG de inicio tardío (inicio de síntomas > 50 años). La relación mujer/hombre fue 1.7/1. La enfermedad se inició más tempranamente en las mujeres que en los hombres, media 32 vs. 48 años (p < 0.0001). La MG familiar autoinmune representó el 3.2 % (6 casos). La forma más común de presentación fue con manifestaciones oculares puras (52%). El 12.1% (23/190) fue considerada MG ocular en el seguimiento. La MG asociada a timoma se presentó en 22 casos (11.6%). El 27.1% presentó otra enfermedad autoinmune asociada, siendo las tiroideas las más frecuentes. El 81.4% tuvo anticuerpos anti-receptores de acetilcolina (ACRA) positivos y 22.7% de los ACRA negativos fueron positivos para anticuerpos anti-tirosina quinasa musculo especifica (anti-MusK). La evolución clínica fue favorable, hallándose más de la mitad de los casos en remisión o manifestaciones mínimas en la última visita. La mayoría requirió inmunosupresión para control de la sintomatología, el 78% recibió corticoides y el 48% un inmunosupresor no esteroideo.

Myasthenia gravis (MG) is an antibody-mediated autoimmune disease of the neuromuscular junction. The aim of this study was to evaluate clinical, epidemiological and serological features of patients with MG in a Public Hospital of Buenos Aires City. A retrospective analysis of 190 patients diagnosed with MG was performed. The mean age of MG onset was 38 years, 30% had late-onset MG (onset age > 50 years). The female/male ratio was 1.7 / 1. Disease started earlier in women than in men, mean 32 vs. 48 years (p < 0.0001). Familial autoimmune MG represented 3.2% of the cases. Most of the patients initiated their disease with a pure ocular form (52%). 12.1% (23/190) were considered ocular MG at follow-up. Thymoma-associated MG represented 11.6% of cases. 27.1% had other associated autoimmune disease, thyroid disorders were the most frequent. 81.4% were anti-acetylcholine receptor antibody (AChR-ab) positive MG; 22.7% of AChR-ab negatives were positive for anti-muscle specific kinase (MusK) antibodies. Clinical outcome was relatively good; more than half of cases were in remission or minimal manifestations at the last visit. The majority of patients required immunosuppression to control the symptoms, 78% received corticosteroids and 48%, a non-steroidal immunosuppressant.

Clinical and genetic analysis of a patient with slow-channel congenital myasthenic syndrome / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a female patient featuring unstable head upright and hypotonia of limbs.@*METHODS@#The child was examined clinically. Peripheral blood samples of the child, her parents and siblings were collected. Genomic DNA was extracted and subjected to next generation sequencing (NGS). Suspected variant was verified by Sanger sequencing and bioinformatic analysis.@*RESULTS@#DNA sequencing found that the patient has carried a de novo heterozygous c.354C>A (p.N118K) variant of the CHRND gene, which was not found in her parents and sibling. Bioinformatics analysis predicted that the variant was likely to be pathogenic. Literature review suggested that the phenotype of the patient was very similar to previously reported ones.@*CONCLUSION@#The child was diagnosed with slow-channel congenital myasthenic syndrome (SCCMS) type 3A caused by heterozygous variant of the CHRND gene. NGS has provided a powerful tool for the diagnosis of such disorders.

Anesthetic considerations for a patient with myasthenia gravis undergoing deep sedation in an outpatient oral surgery setting

Myasthenia gravis (MG) is a neuromuscular autoimmune disorder which clinically presents as muscular weakness and fatigue due to autoantibody formation against acetylcholine receptors (AChR), leading to their subsequent destruction. Due to the neuromuscular implications of MG, certain considerations must be taken into account when providing anesthesia to MG patients. In the following case report, we have outlined procedural considerations for the anesthetic management of a patient with MG undergoing deep sedation for an elective oral surgery in an outpatient setting, as well as a discussion of relevant literature.

Two Cases of Myasthenia Gravis Showing Fatigibility Presenting with Decreased Gain of Smooth Pursuit / 대한평형의학회지

Myasthenia gravis (MG) is an autoimmune disease caused by autoantibodies to the acetylcholine receptors of the neuromuscular junction characterized by weakness and abnormal fatigability of the muscles. Therefore, the diagnosis of MG depends on the recognition of this distinctive pattern of fatigable weakness. Previous studies presented the diagnostic efficacy of saccadic eye movements in patients with ocular MG. We here in report 2 patients of ocular MG showing the fatigue effects during repetitive sustained smooth pursuit, and the effects of the administration of edrophonium on myasthenic smooth pursuit. Changes in smooth pursuits reflecting peripheral and secondary central mechanisms were demonstrated.

Enhancement of T Follicular Helper Cell-Mediated Humoral Immunity Reponses During Development of Experimental Autoimmune Myasthenia Gravis / 神经科学通报·英文版

Myasthenia gravis (MG) is a prototypical antibody-mediated neurological autoimmune disease with the involvement of humoral immune responses in its pathogenesis. T follicular helper (Tfh) cells have been implicated in many autoimmune diseases. However, whether and how Tfh cells are involved in MG remain unclear. Here, we established and studied a widely-used and approved animal model of human MG, the rat model with acetylcholine receptor alpha (AChRα) subunit (R-AChR)-induced experimental autoimmune myasthenia gravis (EAMG). This model presented mild body-weight loss 10 days after the first immunization (representing the early stage of disease) and more obvious clinical manifestations and body-weight loss 7 days after the second immunization (representing the late stage of disease). AChR-specific pre-Tfh cells and mature Tfh cells were detected in these two stages, respectively. In co-cultures of Tfh cells and B cells, the number of IgG2b-secreting B cells and the level of anti-AChR antibodies in the supernatant were higher in the cultures containing EAMG-derived Tfh cells. In immunohistochemistry and immunofluorescence assays, a substantial number of CD4/Bcl-6 T cells and a greater number of larger germinal centers were observed in lymph node tissues resected from EAMG rats. Based on these results, we hypothesize that an AChR-specific Tfh cell-mediated humoral immune response contributes to the development of EAMG.

Mechanism of Th1/Th2 Cytokines in HLA-DQ8 Transgenic Mice Model of Ocular Experimental Autoimmune Myasthenia Gravis / 中国医学科学院学报

Objective To analyze the levels of cytokines (IL-2,IFN-γ,IL-6,IL-10) associated with Th1 and Th2 cells in HLA-DQ8 transgenic mice model of ocular experimental autoimmune myasthenia gravis (oEAMG) induced by recombinant H-AChR γ subunit immunization.Methods DQ8 mice were immunized with 20 μg of AChR γ subunit,20 μg of crude E. coli extract (E. coli group),or complete Freund's adjuvant (CFA) only (CFA group). All mice were immunized on days 0,30,and 60. Mice were euthanized 28 days after the third immunization,and draining lymph node cells (LNC) and spleen lymphocytes were cultured in vitro. The supernatant was collected to observe the interleukin(IL)-2,interferon(IFN)-γ,IL-6,IL-10 production by ELISA.Results LNCs and spleen lymphocytes of H-AChR γ subunit-immunized mice exhibited significantly enhanced IFN-γ (F=76.332,P<0.001;F=34.865,P<0.001) and IL-2 (F=42.835,P<0.001;F=38.030,P<0.001),which associated with Th1 cells,as compared to E. coli group and CFA group. There were no significant differences in IL-6 (F=1.325,P=0.284;F=1.935,P=0.166) and IL-10 (F=0.908,P=0.417;F=1.189,P=0.322) levels,which secreted by Th2 cells,among these three groups.Conclusion Th1 cytokines play key roles in the pathogenesis of oEAMG,while the mechanism of Th2 cytokines for oEAMG remains unclear.

Abstinência à cocaína e suas consequências no sistema colinérgico muscarínico / Abstinencia a la cocaína y sus consecuencias en el sistema colinérgico muscarínico / Abstinence from cocaine and its consequences on the muscarinic cholinergic system

Uma das principais dificuldades enfrentadas na dependência à cocaína está relacionada aos sintomas de abstinência, como ansiedade, desejo e irritabilidade. Estes efeitos podem durar meses ou anos após a interrupção do consumo prolongado, fazendo com que o indivíduo volte a procurá-la. Os efeitos recompensadores da cocaína levam a alterações neurobiológicas do sistema mesocorticolímbico dopaminérgico, que se origina na área tegmental ventral e se projeta para o núcleo accumbens, e córtex pré-frontal, áreas intimamente ligadas ao desenvolvimento da dependência. Esses neurônios dopaminérgicos recebem estímulos dos neurônios colinérgicos que contribuem para os aspectos cognitivos da dependência. Devido à complexidade neurobilógica envolvida durante a abstinência, pouco se sabe sobre as alterações no sistema colinérgico muscarínico durante este período no encéfalo, objetivo deste estudo. Para tal, camundongos machos adultos Swiss-Webster foram submetidos à cocaína em padrão agudo em binge (3×30 mg/kg/dia) e cronicamente por escalonamento de dose em binge por 14 dias (3×15 mg/kg/dia nos dias 1-4; 3×20 mg/kg/dia nos dias 5-8; 3×25 mg/kg/dia nos dias 9-12; e 3×30 mg/kg/dia nos dias 13 e 14). A atividade locomotora de cada animal foi avaliada em campo aberto (CA), onde permaneceram no aparato por 60 minutos entre cada administração. Após o período de exposição os animais permaneceram 14 dias em abstinência, a fim de avaliar a ansiedade no labirinto em cruz elevado (LCE). Em seguida os animais foram eutaniasiados, sendo o córtex pré-frontal (CPF), o estriado e o hipocampo dissecados e armazenados a -80ºC para a análise dos receptores dopaminérgicos D1 e D2, receptores colinérgicos muscarínicos M1, M2, M3, M4 e M5 (mAChRs) e moléculas colinérgicas (acetilcolinesterase, AChE; colina acetiltransferase, ChAT e transportador vesicular de acetilcolina, VAChT) por Western Blotting (n=6). Os resultados comportamentais mostraram maior atividade locomotora nos animais tratados com cocaína no tratamento agudo ou crônico, quando comparado ao basal. Mais ainda, a sensibilização comportamental foi detectada a partir do segundo dia de administração de cocaína. No teste de LCE, realizado 14 dias após a interrupção da administração de cocaína, não foi observada diferença estatística entre os animais previamente expostos à cocaína e grupo controle. No CPF observou-se diminuição de D2R, M1 mAChRs e aumento M2 e M4 mAChRs no tratamento agudo; no tratamento crônico houve diminuição de M1 e M5 mAChRs e ChAT. No estriado observou-se aumento de D1R, M1 e M2 mAChRs, ChAT no tratamento agudo; e aumento D1R, VAChT, ChAT e diminuição D2R, M1 e M2 mAChRs no tratamento crônico. Já no hipocampo observou-se aumento de D1R, D2R, M2 mAChRs, VAChT e diminuição M1 mAChRs no tratamento agudo; e aumento de D1R, VAChT e diminuição D2R, M1 mAChRs no tratamento crônico. Nossos resultados mostram envolvimento de processo de neuroplasticidade, tanto no sistema dopaminérgico quanto no colinérgico muscarínico, em ambos os protocolos utilizados, mesmo após 14 dias de abstinência

Una de las dificultades enfrentadas en la dependencia de cocaína son los síntomas de abstinencia, como ansiedad, deseo y irritabilidad. Estos efectos pueden durar meses o años después de la interrupción del consumo prolongado, haciendo que el individuo vuelva a consumirlo. Los efectos recompensadores de la cocaína causa alteraciones neurobiológicas del sistema mesocorticolímbico dopaminérgico, que se origina en el área tegmental ventral y se proyecta hacia el núcleo accumbens y córtex pré-frontal, áreas íntimamente ligadas al desenvolvimiento de la dependencia. Esas neuronas dopaminérgicas reciben estímulos de neuronas colinérgicas la cual contribuyen para los aspectos cognitivos de la dependencia. Debido a la complejidad neurobiológica involucrada durante la abstinencia, poco se sabe sobre las alteraciones del sistema colinérgico muscarínico durante este periodo en el encéfalo, objetivo de este estudio. Por tanto, ratones adultos macho Swiss-Webster fueron sometidos a cocaína en dosis padrón agudo en binge (3×30 mg/kg/día) y crónicamente por escalonamiento de dosis en binge por 14 días (3×15 mg/kg/día en los días 1-4; 3×20 mg/kg/día en los días 5-8; 3×25 mg/kg/día en los días 9-12; y 3×30 mg/kg/día en los días 13 e 14). La actividad locomotora de cada animal fue evaluada en el test de campo abierto (CA), donde permanecieron por 60 minutos entre cada administración. Después del periodo de exposición los animales permanecieron 14 días de abstinencia, a fin de evaluar la ansiedad en el labirinto de cruz elevado (LCE). En seguida los animales fueron eutanasiados, donde el córtex pré-frontal (CPF), estriado y hipocampo fueron disecados y almacenados a -80ºC para analizar los receptores dopaminérgicos D1 e D2, receptores colinérgicos muscarínicos M1, M2, M3, M4 y M5 (mAChRs) y moléculas colinérgicas (acetilcolinesterasa, AChE; colina acetiltransferasa, ChAT y transportador vesicular de acetilcolina, VAChT) por Western Blotting (n=6). Los resultados comportamentales mostraron mayor actividad locomotora en los animales tratados con cocaína en tratamiento agudo y crónico, comparado al control. Por otra parte, la sensibilización comportamental fue detectado a partir de segundo día de administración de cocaína. En la prueba de LCE, realizado después de 14 días de interrupción de la administración de cocaína, no fue observado diferencia estadística entre los animales previamente expuestos a la cocaína y el grupo control. En CPF se observó disminución de D2R, M1 mAChRs y aumento de M2 y M4 mAChRs en tratamiento agudo; en el tratamiento crónico mostro disminución de M1 y M5 mAChRs y ChAT. En el estriado se observó aumento de D1R, M1 y M2 mAChRs, ChAT en el tratamiento agudo; aumento D1R, VAChT, ChAT y disminución de D2R, M1 y M2 mAChRs en el tratamiento crónico. Por último, en el hipocampo se observó aumento de D1R, D2R, M2 mAChRs, VAChT y disminución M1 mAChRs en el tratamiento agudo; aumento de D1R, VAChT y disminución D2R, M1 mAChRs en el tratamiento crónico. Nuestros resultados muestran envolvimiento de procesos de neuroplasticidad, tanto en el sistema dopaminérgico como el sistema colinérgico muscarínico, en ambos protocolos utilizados, después de 14 días de abstinencia

Blepharospasm with elevated anti-acetylcholine receptor antibody titer / Blefaroespasmo com título elevado de anticorpos antirreceptores de acetilcolina

ABSTRACT Objective: To determine whether serum levels of anti-acetylcholine receptor antibody (anti-AChR-Abs) are related to clinical parameters of blepharospasm (BSP). Methods: Eighty-three adults with BSP, 60 outpatients with hemifacial spasm (HFS) and 58 controls were recruited. Personal history, demographic factors, response to botulinum toxin type A (BoNT-A) and other neurological conditions were recorded. Anti-AChR-Abs levels were quantified using an enzyme-linked immunosorbent assay. Results: The anti-AChR Abs levels were 0.237 ± 0.022 optical density units in the BSP group, which was significantly different from the HFS group (0.160 ± 0.064) and control group (0.126 ± 0.038). The anti-AChR Abs level was correlated with age and the duration of response to the BoNT-A injection. Conclusion: Patients with BSP had an elevated anti-AChR Abs titer, which suggests that dysimmunity plays a role in the onset of BSP. An increased anti-AChR Abs titer may be a predictor for poor response to BoNT-A in BSP.

RESUMO Objetivo: Determinar se os níveis séricos do anticorpo antirreceptor de acetilcolina (anti-AChR-Abs) estão relacionados aos parâmetros clínicos do blefaroespasmo (BSP). Métodos: Fora recrutados 83 adultos com BSP, 60 pacientes ambulatoriais com espasmo hemifacial (HFS) e 58 controles. Foi aplicado um questionário para registrar história pessoal, fatores demográficos, resposta à toxina botulínica tipo A (BoNT-A) e outras condições neurológicas. Os níveis de anti-AChR-Abs foram quantificados usando um ensaio imunoenzimático. Resultados: O nível de anti-AChR-Abs foi de 0,237 ± 0,022 unidades de densidade óptica (OD) no grupo BSP, significativamente diferente em comparação com o grupo HFS (0,160 ± 0,064) e o grupo controle (0,126 ± 0,038). O nível de anti-AChR-Abs se correlacionou com a idade e a duração da resposta à injeção de BoNT-A. Conclusão: Pacientes com BSP apresentaram títulos elevados de anti-AChR-Abs, o que sugere que a desimunidade desempenha um papel no surgimento de BSP. O aumento do título de anti-AChR-Abs pode ser um preditor de resposta insuficiente à BoNT-A em BSP.

Neuroprotective effect of the ethanol extract of Artemisia capillaris on transient forebrain ischemia in mice via nicotinic cholinergic receptor / 中国天然药物

Artemisia capillaris Thunberg is a medicinal plant used as a traditional medicine in many cultures. It is an effective remedy for liver problems including hepatitis. Recent pharmacological reports have indicated that Artemisia species can exert various neurological effects. Previously, we reported a memory-enhancing effect of Artemisia species. However, the mechanisms underlying the neuroprotective effect of A. capillaris (AC) are still unknown. In the present study, we investigated the effect of an ethanol extract of AC on ischemic brain injury in a mouse model of transient forebrain ischemia. The mice were treated with AC for seven days, beginning one day before induction of transient forebrain ischemia. Behavioral deficits were investigated using the Y-maze. Nissl and Fluoro-jade B staining were used to indicate the site of injury. To determine the underlying mechanisms for the drug, we measured acetylcholinesterase activity. AC (200 mg·kg) treatment reduced transient forebrain ischemia-induced neuronal cell death in the hippocampal CA1 region. The AC-treated group also showed significant amelioration in the spontaneous alternation of the Y-maze test performance, compared to that in the untreated transient forebrain ischemia group. Moreover, AC treatment showed a concentration-dependent inhibitory effect on acetylcholinesterase activity in vitro. Finally, the effect of AC on forebrain ischemia was blocked by mecamylamine, a nonselective nicotinic acetylcholine receptor antagonist. Our results suggested that in a model of forebrain ischemia, AC protected against neuronal death through the activation of nicotinic acetylcholine receptors.

Neuroprotective effect of the ethanol extract of Artemisia capillaris on transient forebrain ischemia in mice via nicotinic cholinergic receptor / 中国天然药物

Artemisia capillaris Thunberg is a medicinal plant used as a traditional medicine in many cultures. It is an effective remedy for liver problems including hepatitis. Recent pharmacological reports have indicated that Artemisia species can exert various neurological effects. Previously, we reported a memory-enhancing effect of Artemisia species. However, the mechanisms underlying the neuroprotective effect of A. capillaris (AC) are still unknown. In the present study, we investigated the effect of an ethanol extract of AC on ischemic brain injury in a mouse model of transient forebrain ischemia. The mice were treated with AC for seven days, beginning one day before induction of transient forebrain ischemia. Behavioral deficits were investigated using the Y-maze. Nissl and Fluoro-jade B staining were used to indicate the site of injury. To determine the underlying mechanisms for the drug, we measured acetylcholinesterase activity. AC (200 mg·kg) treatment reduced transient forebrain ischemia-induced neuronal cell death in the hippocampal CA1 region. The AC-treated group also showed significant amelioration in the spontaneous alternation of the Y-maze test performance, compared to that in the untreated transient forebrain ischemia group. Moreover, AC treatment showed a concentration-dependent inhibitory effect on acetylcholinesterase activity in vitro. Finally, the effect of AC on forebrain ischemia was blocked by mecamylamine, a nonselective nicotinic acetylcholine receptor antagonist. Our results suggested that in a model of forebrain ischemia, AC protected against neuronal death through the activation of nicotinic acetylcholine receptors.

Updated review of resistance to neuromuscular blocking agents

Since neuromuscular blocking agents (NMBAs) were introduced to the surgical field, they have become almost mandatory for the induction and maintenance of anesthesia. However, resistance to NMBAs can develop in certain pathological states, such as central nerve injury, burns, and critical illnesses. During such pathological processes, quantitative and qualitative changes occur in the physiology of acetylcholine and the acetylcholine receptor (AChR) at the neuromuscular junction. Up-regulation of AChR leads to changes in the pharmacokinetics and pharmacodynamics of NMBA. As NMBA resistance may result in problems during anesthesia, it is of utmost importance to understand the mechanisms of NMBA resistance and their associations with pathological status to maintain adequate neuromuscular relaxation. This review presents the current knowledge of pharmacokinetic and pharmacodynamic changes and pathological status associated with NMBA resistance.

Methidathion Poisoning / 대한구급학회지

Although methidathion is an organophosphate insecticide, it is different from the other organophosphates in terms of toxicity. Because of its relatively high fat solubility, the apparent volume of methidathion distribution throughout the body is very high, indicating that hemoperfusion is not effective in removing this organophosphate from the body. Redistribution of methidathion from fat to blood can also occur when plasma levels diminish. Additionally, acetylcholinesterase aging, which is the loss of an alkyl side chain that prevents reactivation by oximes, is very rapid so that the effective reactivation by oximes is thwarted. Thus, methidathion's effect on acetylcholinesterase inhibition is long lasting, particularly with a high dose. In addition to its parasympatholytic effect and ability to induce muscle paralysis, methidathion poisoning is associated with a profound and long-lasting circulatory collapse due to sympathetic ganglion blockade. This report presents the case of a 55-year-old man who accidentally ingested a high dose of methidathion. He later developed enteroinvasive aspergillosis infection-induced multiple bowel perforations on two separate occasions while on mechanical ventilator support, resulting in a fatal outcome. The renin-angiotensin axis activated by sympathetic ganglion blockade may have reduced the patient's splanchnic blood flow, contributing to translocation of endotoxin. Also, the effect of excessive acetylcholine on non-neuronal acetylcholine receptors may have contributed to the development of fatal enteroinvasive aspergillosis in this patient.

Combination of musk and olibanum promotes proliferation of prostate stem cells in mice: An experimental study / 中华男科学杂志

Objective@#To study the effects of muskolibanum combination on the proliferation and differentiation of prostate stem cells.@*METHODS@#We cultured prostate epithelial cells and urogenital sinus mesenchymal (UGSM) cells from 7－10 d old C57BL/6 mice and 16－18 d old pregnant C57BL/6 mice, transplanted the mixed suspension of the two types of cells under the kidney envelope of SCIDCB.17 male mice, and harvested the transplants 30 days later. We randomly divided the SCIDCB.17 mice into four groups to be treated intragastrically with musk (n = 8), olibanum (n = 8), musk+olibanum (n = 7), and normal saline (blank control, n = 8)) respectively, all for 14 days. Then we collected the kidney tissue for observation of the morphology of the glandular tubes and differentiation of different subsets of stem cells by HE staining and determination of the expressions and distribution of P63, CD133, CD117 and Sca1 by immunohistochemistry and Western blot.@*RESULTS@#A system was successfully established for the isolation and mixed culture of Sca1 Lin+ CD49f+ (LSC) cells of prostate stem cells and UGSM cells of the mouse embryonic prostate. Immunohistochemistry showed positive expressions of P63, CD133, Sca1, and CD117 in the prostatic acinar epithelia and proved the presence of prostatic acinar epithelial structure in the transplants. Compared with the blank control group, the expressions of CD133, Sca1 and CD117 were significantly increased in the musk, olibanum, and musk+olibanum groups (P< 0.05), higher in the musk+olibanum than in the musk or olibanum group (P< 0.05), and their protein expressions were even more elevated in the musk+olibanum group (P< 0.01), with statistically significant difference from the olibanum group (P< 0.05).@*CONCLUSIONS@#The combination of musk and olibanum can improve the proliferation and differentiation of prostate stem cells.

The efficacy of combination treatment of gabapentin and electro-acupuncture on paclitaxel-induced neuropathic pain

Paclitaxel, a chemotherapeutic drug, induces severe peripheral neuropathy. Gabapentin (GBT) is a first line agent used to treat neuropathic pain, and its effect is mediated by spinal noradrenergic and muscarinic cholinergic receptors. Electro-acupuncture (EA) is used for treating various types of pain via its action through spinal opioidergic and noradrenergic receptors. Here, we investigated whether combined treatment of these two agents could exert a synergistic effect on paclitaxel-induced cold and mechanical allodynia, which were assessed by the acetone drop test and von Frey filament assay, respectively. Significant signs of allodynia were observed after four paclitaxel injections (a cumulative dose of 8 mg/kg, i.p.). GBT (3, 30, and 100 mg/kg, i.p.) or EA (ST36, Zusanli) alone produced dose-dependent anti-allodynic effects. The medium and highest doses of GBT (30 and 100 mg/kg) provided a strong analgesic effect, but they induced motor dysfunction in Rota-rod tests. On the contrary, the lowest dose of GBT (3 mg/kg) did not induce motor weakness, but it provided a brief analgesic effect. The combination of the lowest dose of GBT and EA resulted in a greater and longer effect, without inducing motor dysfunction. This effect on mechanical allodynia was blocked by spinal opioidergic (naloxone, 20 μg), or noradrenergic (idazoxan, 10 μg) receptor antagonist, whereas on cold allodynia, only opioidergic receptor antagonist blocked the effect. In conclusion, the combination of the lowest dose of GBT and EA has a robust and enduring analgesic action against paclitaxel-induced neuropathic pain, and it should be considered as an alternative treatment method.

Methidathion Poisoning / 대한중환자의학회지

Although methidathion is an organophosphate insecticide, it is different from the other organophosphates in terms of toxicity. Because of its relatively high fat solubility, the apparent volume of methidathion distribution throughout the body is very high, indicating that hemoperfusion is not effective in removing this organophosphate from the body. Redistribution of methidathion from fat to blood can also occur when plasma levels diminish. Additionally, acetylcholinesterase aging, which is the loss of an alkyl side chain that prevents reactivation by oximes, is very rapid so that the effective reactivation by oximes is thwarted. Thus, methidathion's effect on acetylcholinesterase inhibition is long lasting, particularly with a high dose. In addition to its parasympatholytic effect and ability to induce muscle paralysis, methidathion poisoning is associated with a profound and long-lasting circulatory collapse due to sympathetic ganglion blockade. This report presents the case of a 55-year-old man who accidentally ingested a high dose of methidathion. He later developed enteroinvasive aspergillosis infection-induced multiple bowel perforations on two separate occasions while on mechanical ventilator support, resulting in a fatal outcome. The renin-angiotensin axis activated by sympathetic ganglion blockade may have reduced the patient's splanchnic blood flow, contributing to translocation of endotoxin. Also, the effect of excessive acetylcholine on non-neuronal acetylcholine receptors may have contributed to the development of fatal enteroinvasive aspergillosis in this patient.

Activation of acetylcholine receptor elicits intracellular Ca2+ mobilization, transient cytotoxicity, and induction of RANKL expression

Acetylcholine receptors (AChR) including muscarinic and nicotinic AChR are widely expressed and mediate a variety of physiological cellular responses in neuronal and non-neuronal cells. Notably, a functional cholinergic system exists in oral epithelial cells, and nicotinic AChR (nAChR) mediates cholinergic anti-inflammatory responses. However, the pathophysiological roles of AChR in periodontitis are unclear. Here, we show that activation of AChR elicits increased cytosolic Ca²⁺ ([Ca²⁺]ᵢ), transient cytotoxicity, and induction of receptor activator of nuclear factor kappa-B ligand (RANKL) expression. Intracellular Ca²⁺ mobilization in human gingival fibroblast-1 (hGF-1) cells was measured using the fluorescent Ca²⁺ indicator, fura-2/AM. Cytotoxicity and induction of gene expression were evaluated by measuring the release of glucose-6-phosphate dehydrogenase and RT-PCR. Activation of AChR in hGF-1 cells by carbachol (Cch) induced [Ca²⁺]ᵢ increase in a dose-dependent manner. Treatment with a high concentration of Cch on hGF-1 cells caused transient cytotoxicity. Notably, treatment of hGF-1 cells with Cch resulted in upregulated RANKL expression. The findings may indicate potential roles of AChR in gingival fibroblast cells in bone remodeling.

A Case of Ileus in a Patient with Schizophrenia Under Paliperidone Palmitate Treatment

Constipation is a side effect of antipsychotic drugs that have high affinity for muscarinic cholinergic receptors. In addition, ileus is an important side effect of antipsychotic treatment, with potentially morbid and mortal consequences if early detection fails. In this report, a colonic ileus case is described in a patient with schizophrenia under the treatment of paliperidone palmitate. Consequently, complete physical examination and close screening of side effects are recommended when antipsychotics are prescribed.

Single-fiber Electromyography in the Extensor Digitorum Communis for the Predictive Prognosis of Ocular Myasthenia Gravis: A Retrospective Study of 102 Cases / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Single-fiber electromyography (SFEMG) abnormality in the extensor digitorum communis (EDC) was reported in ocular myasthenia gravis (OMG), which indicated subclinical involvement beyond extraocular muscles in OMG patients. The relationship between the abnormal findings of SFEMG in EDC and the probability for OMG to develop generalized myasthenia gravis (GMG) is unknown. This retrospective study aimed to determine the predictive value of abnormality of SFEMG in EDC of OMG patients.</p><p><b>METHODS</b>One-hundred and two OMG patients underwent standard clinical diagnosis process and SFEMG test in EDC muscle when diagnosed and were clinically followed up for 5 years. The SFEMG data were compared between different clinical groups according to thymus status, onset age, and different outcome of OMG developing. Chances of progressing to GMG were compared between two different groups according to SFEMG and repetitive nerve stimulation (RNS) results, acetylcholine receptor antibody (AchRAb) titer, thymus status, and onset age.</p><p><b>RESULTS</b>Abnormal SFEMG results were observed in 84 (82.4%) patients. The mean jitter, percentage of jitter >55 μs (%), and blocking were higher in OMG patients than in healthy volunteers. There were no statistical differences in jitter analysis between thymoma group and non-thymoma group (P = 0.65), or between the later OMG group and the later GMG group (P = 0.31), including mean jitter, percentage of jitter >55 μs (%), and blocking. Elderly group (≥45 years old) had a higher mean jitter than younger group (t = 2.235, P = 0.028). Total 55 OMG developed GMG, including 47 in abnormal SFEMG group while 8 in normal SFEMG group. There was no statistical difference in the conversion rates between the two groups (χ2 = 0.790, P = 0.140). RNS abnormality, AchRab titer, or onset age had no correlation with OMG prognosis (P = 0.150, 0.070, 0.120, respectively) while thymoma did (χ2 = 0.510, P = 0.020).</p><p><b>CONCLUSION</b>SFEMG test in the EDC showed high abnormality in OMG, suggesting subclinical involvement other than extraocular muscles. Nevertheless, the abnormal jitter analysis did not predict the prognosis of OMG according to clinical follow-up.</p>

The Effect of Urocortin 1 on Motility in Isolated, Vascularly Perfused Rat Colon / 대한소화기학회지

BACKGROUND/AIMS: Urocortin 1, a corticotropin-releasing factor related peptide, increases colonic motility under stressful conditions. We investigated the effect of urocortin 1 on colonic motility using an experimental model with isolated rat colon in which the blood flow and intestinal nerves were preserved. Furthermore, we assessed whether this effect was mediated by adrenergic or cholinergic nerves. METHODS: Colonic motility was measured in the proximal and distal parts of resected rat colon. The colon resected from the peritoneum was stabilized, and then urocortin 1 (13.8, 138, 277, and 1,388 pM) was administered via a blood vessel. Motility index was measured in the last 5 min of the 15 min administration of urocortin 1 and expressed as percentage change from baseline. Subsequently, the change in motility was measured by perfusing urocortin 1 in colons pretreated with phentolamine, propranolol, hexamethonium, atropine, or tetrodotoxin. RESULTS: At concentrations of 13.8, 138, 277, and 1,388 pM, urocortin 1 increased the motility of proximal colon (20.4+/-7.2%, 48.4+/-20.9%, 67.0+/-25.8%, and 64.2+/-20.9%, respectively) and the motility of distal colon (3.3+/-3.3%, 7.8+/-7.8%, 71.1+/-28.6%, and 87.4+/-32.5%, respectively). The motility induced by urocortin 1 was significantly decreased by atropine to 2.4+/-2.4% in proximal colon and 3.4+/-3.4% in distal colon (p<0.05). However, tetrodotoxin, propranolol, phentolamine, and hexamethonium did not inhibit motility. CONCLUSIONS: Urocortin 1 increased colonic motility and it is considered that this effect was directly mediated by local muscarinic cholinergic receptors.