RESUMEN
PURPOSE: This observational study aimed to elucidate the pathophysiology of subchondral cysts (SC) in the temporomandibular joint (TMJ) and examine the results of conservative therapy administered to patients with SCs in the TMJ. METHODS: The study included 41 patients with SCs, extracted from 684 consecutive patients who underwent magnetic resonance imaging (MRI). The anatomical features of SCs and positional abnormalities of the articular disc were initially evaluated using MRI. A second MRI examination was performed for 28/41 patients at 40-107 months (mean, 66 months) after the first MRI. The joint space, anteroposterior width of the condylar head (WiC), articular eminence angle (AEA), and visual analog scale of jaw pain (VAS) were assessed alongside the MRI examinations. RESULTS: Most SCs were present in the anterosuperior and central condyle. Disc displacement was observed in 100% of 42 TMJs with SCs. Of the 29 joints in 28 patients, SCs in 19 joints resolved with time, whereas SCs in 10 joints persisted. A significant increase in the WiC and a significant decrease in AEA and VAS scores were observed on the second MRI scan. CONCLUSIONS: SCs tended to form in the anterosuperior and central parts of the condyle, where mechanical loading was likely to be applied. SCs are strongly associated with articular disc displacement. Two-thirds of SCs resolved over time, accompanied by resorption and osteophytic deformation of the condyle. SC might not be an indicator for the start of surgical treatment, and nonsurgical treatment could improve the clinical symptoms of patients with SCs.
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Quistes Óseos , Luxaciones Articulares , Trastornos de la Articulación Temporomandibular , Humanos , Estudios de Seguimiento , Estudios Transversales , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/patología , Trastornos de la Articulación Temporomandibular/diagnóstico por imagen , Trastornos de la Articulación Temporomandibular/terapia , Articulación Temporomandibular/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Quistes Óseos/diagnóstico por imagen , Quistes Óseos/patología , Luxaciones Articulares/patología , Luxaciones Articulares/terapiaRESUMEN
Fish live in water with a different osmotic pressure from that in the body. Their gills have chloride cells that transport ions to maintain an appropriate level of osmotic pressure in the body. The direction of ion transport is different between seawater and freshwater. There are two types of chloride cells that specialize in unidirectional transport and generalist cells that can switch their function quickly in response to environmental salinity. In species that experience salinity changes throughout life (euryhaline species), individuals may replace some chloride cells with cells of different types upon a sudden change in environmental salinity. In this paper, we develop a dynamic optimization model for the chloride cell composition of an individual living in an environment with randomly fluctuating salinity. The optimal solution is to minimize the sum of the workload of chloride cells in coping with the difference in osmotic pressure, the maintenance cost, and the temporal cost due to environmental change. The optimal fraction of generalist chloride cells increases with the frequency of salinity changes and the time needed for new cells to be fully functional but decreases with excess maintenance cost.
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Cloruros , Osmorregulación , Animales , Cloruros/metabolismo , Branquias/metabolismo , Osmorregulación/fisiología , Salinidad , Agua de Mar , Equilibrio HidroelectrolíticoRESUMEN
OBJECTIVE: The purpose of this study was to compare images generated by a multiple-echo recombined gradient echo (MERGE) with the proton density-weighted fast spin-echo (PD-weighted FSE) sequence, T1-weighted fast spin-echo sequence (T1-weighted FSE), and T2-weighted fast spin-echo sequence (T2-weighted FSE) for the diagnostic imaging of the temporomandibular joint (TMJ). MATERIALS AND METHODS: Twenty-three patients with signs and symptoms of TMJ dysfunction were enrolled in this study. The four imaging modalities were used to examine the TMJ. Three images (lateral, middle, and medial parts of the condylar head) were reviewed by two radiologists, who rated the visibility of the disk and cortex of the condylar head. RESULTS: For the medial part of the TMJ, in cases with a normally positioned disk, the results of the MERGE and PD-weighted FSE techniques were significantly better than those of the T1-weighted FSE and T2-weighted FSE. For visibility of the cortex in the normally positioned disk, MERGE was significantly better than PD-weighted FSE [P < 0.0125 (0.05/4)] at the middle and medial parts of the TMJ. MERGE was also significantly better than T1-weighted FSE [P < 0.0125 (0.05/4)] and T2-weighted FSE [P < 0.0125 (0.05/4)]. CONCLUSION: MERGE is better for visualizing the condylar only at the middle and the medial aspects of the TMJ in a normally positioned disk.
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Imagen por Resonancia Magnética , Síndrome de la Disfunción de Articulación Temporomandibular , Humanos , Imagen por Resonancia Magnética/métodos , Articulación Temporomandibular/diagnóstico por imagenRESUMEN
OBJECTIVES: The FTO gene has been reported as an obesity-associated gene and is also considered a risk gene for osteoarthritis (OA). However, its exact function is unclear, and there is conflicting evidence on the involvement of FTO polymorphisms in OA via obesity. The purpose of this study was to determine the effects of FTO polymorphism rs8044769 alleles on OA in the temporomandibular joint (TMJ), which is minimally affected by body weight. MATERIALS AND METHODS: A total of 324 TMJs (113 with OA and 211 without OA, serving as controls) from 162 Japanese patients with temporomandibular disorders and undergoing MRI examination were analyzed. Genotyping was conducted, and multivariate analysis was performed after adjusting for the effects of age, sex, body mass index, and TMJ disc abnormalities. RESULTS: Mean age, BMI, and sex did not differ between the TMJs with OA and the TMJs without OA, but a significant difference was found for positional and dynamic disc abnormalities (P < 0.05). The allele frequency of FTO polymorphisms also differed significantly between the TMJs with OA and the TMJs without OA (P = 0.011). Moreover, logistic regression analysis showed no significant association between BMI (P = 0.581) and the occurrence of TMJOA but also indicated that the CC allele of rs8044769 is a risk factor for TMJOA (P = 0.040). CONCLUSIONS: Our results show that rs8044769 in the FTO gene might be involved in TMJOA. CLINICAL RELEVANCE: The present study provides a basis for a deeper understanding of the mechanism underlying degenerative skeletal diseases and the more effective selection and development of treatment strategies based on the patients' genetic characteristics.
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Osteoartritis , Trastornos de la Articulación Temporomandibular , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Humanos , Polimorfismo Genético/genética , Articulación Temporomandibular , Disco de la Articulación Temporomandibular , Trastornos de la Articulación Temporomandibular/genéticaRESUMEN
OBJECTIVES: Oral cancer is the eighth most common type of cancer worldwide and a significant contributor to the global burden caused by this disease. The principal parameters considered to influence prognosis, and thus treatment selection, are size and location of the primary tumor, as well as assessment of the presence and extent of lymph node and distant metastasis (DM). However, no known report regarding the relationship between the primary site and DM has been presented. For effective treatment selection and good prognosis, the correlation of DM with anatomic site and histopathology results of the primary malignancy is important. In the present study, we performed a systematic review of published reports in an effort to determine the relationship between the anatomic site of various types of oral cavity cancer and DM. METHODS: A systematic review of articles published until the end of 2018 was performed using PubMed/MEDLINE. RESULTS: A total of 150 studies were selected for this review. The percentage of all cases reported with DM was 6.3%, ranging from 0.6% to 33.1% in the individual studies. The rate of incidence of tongue occurrence was 9.3%. A frequent DM site was the lungs, with adenoid cystic carcinoma the most commonly involved histopathological factor. Malignant melanoma was most frequent (43.4%) in all histopathology findings, whereas there were no cases with an acinic cell carcinoma or cystadenocarcinoma. CONCLUSIONS: We found that the occurrence of DM from the primary site as well as rate of incidence was dependent on histopathological factors.
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Carcinoma Adenoide Quístico , Neoplasias de la Boca , Humanos , Ganglios Linfáticos , Estudios RetrospectivosRESUMEN
A 74-year-old man was admitted to a clinic because of epigastralgia in June 2018. He was referred to our hospital for further examination of right hydronephrosis. He was diagnosed as having type 2 gastric cancer in the middle gastric body and lesser curvature, with an upper gastric fiber, swollen para-aortic lymph node, and right hydronephrosis by using abdominal computed tomography. PET-CT revealed no hot spot in the para-aortic lymph node but revealed a hot spot in the lower small bowel. He was admitted to our hospital because of severe abdominal pain and appetite loss and underwent a reduction and palliative surgery for the unresectable gastric cancer. The omental cavity was perforated and penetrated into the retroperitoneum. He underwent esophageal jejunal bypass and intestinal fistula tube insertion in the stomach. He had a central vein port and was discharged from our hospital. He was able to eat during his short overnight stay at our hospital after the operation but died on postoperative day 30.
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Gastropatías/cirugía , Neoplasias Gástricas , Abdomen , Anciano , Humanos , Ganglios Linfáticos , Masculino , Tomografía Computarizada por Tomografía de Emisión de Positrones , Gastropatías/etiología , Neoplasias Gástricas/complicaciones , Neoplasias Gástricas/cirugíaRESUMEN
Neurofibromatosis type 1 (NF1) was first described in 1882 as a hamartomatous disorder of neural crest derivation. We present the imaging of a 65-year-old woman with NF1. Computed tomography revealed that there were three major findings presented: skeletal deformity, an area of fat (probably related to mesodermal dysplasia), and benign neoplasm within the masticator space. Moreover, masticatory muscles were hypoplastic.
RESUMEN
OBJECTIVES: Our goal was to assess MR image uniformity by investigating aspects influencing said uniformity via a method laid out by the National Electrical Manufacturers Association (NEMA). METHODS: Six metallic materials embedded in a glass phantom were scanned (i.e. Au, Ag, Al, Au-Ag-Pd alloy, Ti and Co-Cr alloy) as well as a reference image. Sequences included spin echo (SE) and gradient echo (GRE) scanned in three planes (i.e. axial, coronal, and sagittal). Moreover, three surface coil types (i.e. head and neck, Brain, and temporomandibular joint coils) and two image correction methods (i.e. surface coil intensity correction or SCIC, phased array uniformity enhancement or PURE) were employed to evaluate their effectiveness on image uniformity. Image uniformity was assessed using the National Electrical Manufacturers Association peak-deviation non-uniformity method. RESULTS: Results showed that temporomandibular joint coils elicited the least uniform image and brain coils outperformed head and neck coils when metallic materials were present. Additionally, when metallic materials were present, spin echo outperformed gradient echo especially for Co-Cr (particularly in the axial plane). Furthermore, both SCIC and PURE improved image uniformity compared to uncorrected images, and SCIC slightly surpassed PURE when metallic metals were present. Lastly, Co-Cr elicited the least uniform image while other metallic materials generally showed similar patterns (i.e. no significant deviation from images without metallic metals). CONCLUSIONS: Overall, a quantitative understanding of the factors influencing MR image uniformity (e.g. coil type, imaging method, metal susceptibility, and post-hoc correction method) is advantageous to optimize image quality, assists clinical interpretation, and may result in improved medical and dental care.
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Encéfalo , Imagen por Resonancia Magnética , Artefactos , Encéfalo/diagnóstico por imagen , Humanos , Aumento de la Imagen , Fantasmas de Imagen , Dióxido de SilicioRESUMEN
AIM: The purpose of this study was to assess the impairment of the submandibular gland, in terms of changes in volume by computed tomography (CT) and CT value, which was the mean pixel value at a region of interest, in a group of patients with head and neck cancer treated with radiation therapy (RT). PATIENTS AND METHODS: Eleven patients treated with RT, where the effective radiation dose to the submandibular gland was known, were included in the study. CT scanning was performed both before and after RT. The average follow-up period after RT was 555 days (range=107-1231 days). RESULTS: The mean volume of the submandibular gland decreased by around 38% (p<0.001) compared to the pre-treatment average until 600 days after RT. The mean CT value of the submandibular gland decreased until 200 days after RT (p<0.05). CONCLUSION: Both volume and CT value of the submandibular gland showed signs of impairment of the gland during the first several months after RT for head and neck cancer.
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Irradiación Craneana/efectos adversos , Neoplasias de la Boca/radioterapia , Glándula Submandibular/efectos de la radiación , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/diagnóstico por imagen , Neoplasias de la Boca/patología , Tamaño de los Órganos/efectos de la radiación , Estudios Retrospectivos , Glándula Submandibular/diagnóstico por imagen , Glándula Submandibular/patología , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
Cystoisospora suis is a pathogen that causes diarrhea in pigs and can lead to serious disease. Species identification, especially by histopathological examination, is often difficult because of morphologically similar parasites such as Eimeria species. In this study, we used histopathological, bacteriological, virological, and parasitological methods to identify the cause of the disease in two piglets with severe diarrhea. Villous atrophy, diffuse necrosis, and flattening of mucosal epithelial cells were found in the ilea of examined piglets, and coccidian parasites were found in the cytoplasm of the epithelial cells. In some merozoites in the meronts, the presence of two nuclei indicated type 1 merozoites, characteristic of C. suis. According to Cystoisospora-specific PCR targeting the rRNA internal transcribed spacer 1 (ITS1) gene, the sequences of the products were 98.5% similar to those of C. suis. Escherichia coli (O149 serogroup) exhibiting a virulence factor profile (LT, STb, and EAST1 as toxins and F4 as a colonization factor) was detected in one piglet. No other bacteria or significant enteric viruses were found. Co-infection with C. suis and E. coli could imply aggravation of the disease, although further study is needed to assess the pathogenicity of this interaction. This study is the first to clarify by molecular analysis the sequences of C. suis detected in piglets in Japan.
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Coccidiosis/veterinaria , Diarrea/veterinaria , Sarcocystidae/aislamiento & purificación , Enfermedades de los Porcinos/parasitología , Animales , Análisis por Conglomerados , Coccidiosis/parasitología , Coccidiosis/patología , ADN Protozoario/química , ADN Protozoario/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Diarrea/parasitología , Diarrea/patología , Células Epiteliales/parasitología , Histocitoquímica , Íleon/patología , Japón , Filogenia , Reacción en Cadena de la Polimerasa , Sarcocystidae/clasificación , Sarcocystidae/genética , Análisis de Secuencia de ADN , Porcinos , Enfermedades de los Porcinos/patologíaRESUMEN
The aim of this study was to determine the relationship between the pathogenic duration of rheumatoid arthritis in joints other than the temporomandibular joint and bone and soft tissue involvement of the temporomandibular joint using magnetic resonance imaging. Twenty-six symptomatic patients diagnosed with rheumatoid arthritis were enrolled in this study. All patients were classified according to the duration of rheumatoid arthritis in joints other than the temporomandibular joint. The relationships between the duration of rheumatoid arthritis in these various joints and magnetic resonance findings in the temporomandibular joint were analyzed using the chi-square test. Bony changes in the mandibular condyle were observed in 43 of 52 (82.7 %) temporomandibular joints, but the frequency of such changes was not significantly correlated with the duration of rheumatoid arthritis in other joints. We found a significant correlation between the duration of rheumatoid arthritis in other joints and the type and number of bony changes in the mandibular condyle (P < 0.05). Superior disc positions were observed in 27 of 52 (51.9 %) temporomandibular joints. T2-weighted images demonstrated effusion in the joint space in 38 of 52 (73.1 %) temporomandibular joints. A biplanar disc configuration was the most frequent configuration in all groups. The duration of rheumatoid arthritis in other joints was significantly correlated with the mobility of the mandibular condyle (P < 0.05). The type and number of bony changes and mobility of the mandibular condyle showed significant relationships with the duration of rheumatoid arthritis in other joints in the body (P < 0.05).
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Artritis Reumatoide/patología , Articulación Temporomandibular/patología , Adulto , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Cóndilo Mandibular/patología , Persona de Mediana EdadRESUMEN
OBJECTIVE: The purpose of this study was to investigate the usefulness of computerized tomography (CT), particularly contrast-enhanced CT, in differentiation of jaw cysts and cystic-appearing tumors. STUDY DESIGN: We retrospectively analyzed contrast-enhanced CT images of 90 patients with odontogenic jaw cysts or cystic-appearing tumors. The lesion size and CT values were measured and the short axis to long axis (S/L) ratio, contrast enhancement (CE) ratio, and standard deviation ratio were calculated. RESULTS: The lesion size and the S/L ratio of keratocystic odontogenic tumors were significantly different from those of radicular cysts and follicular cysts. There were no significant differences in the CE ratio among the lesions. CONCLUSIONS: Multidetector CT provided diagnostic information about the size of odontogenic cysts and cystic-appearing tumors of the jaws that was related to the lesion type, but showed no relation between CE ratio and the type of these lesions.
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Quistes Odontogénicos/diagnóstico por imagen , Tumores Odontogénicos/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Análisis Discriminante , Femenino , Humanos , Yohexol , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estadísticas no ParamétricasRESUMEN
Sofalcone, 2'-carboxymethoxy-4,4-bis(3-methyl-2-butenyloxy)chalcone, is an anti-ulcer agent that is classified as a gastric mucosa protective agent. Recent studies indicate heat shock proteins such as HSP32, also known as heme-oxygenase-1(HO-1), play important roles in protecting gastrointestinal tissues from several stresses. We have previously reported that sofalcone increases the expression of HO-1 in adipocytes and pre-adipocytes, although the effect of sofalcone on HO-1 induction in gastrointestinal tissues is not clear. In the current study, we investigated the effects of sofalcone on the expression of HO-1 and its functional role in rat gastric epithelial (RGM-1) cells. We found that sofalcone increased HO-1 expression in RGM-1 cells in both time- and concentration-dependent manners. The HO-1 induction was associated with the nuclear translocation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in RGM-1 cells. We also observed that sofalcone increased vascular endothelial growth factor (VEGF) production in the culture medium. Treatment of RGM-1 cells with an HO-1 inhibitor (tin-protoporphyrin), or HO-1 siRNA inhibited sofalcone-induced VEGF production, suggesting that the effect of sofalcone on VEGF expression is mediated by the HO-1 pathway. These results suggest that the gastroprotective effects of sofalcone are partly exerted via Nrf2-HO-1 activation followed by VEGF production.
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Antiulcerosos/farmacología , Chalconas/farmacología , Citoprotección , Mucosa Gástrica/efectos de los fármacos , Hemo-Oxigenasa 1/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Animales , Línea Celular , Mucosa Gástrica/irrigación sanguínea , Mucosa Gástrica/metabolismo , Técnicas de Silenciamiento del Gen , Hemo-Oxigenasa 1/genética , Neovascularización Fisiológica/efectos de los fármacos , ARN Interferente Pequeño/genética , RatasRESUMEN
Angiosarcoma is a rare malignant neoplasm and primary angiosarcoma is extremely rare. This study reports clinico-pathological features and CT image finding of a case of primary angiosarcoma in the upper gingival and a review of previously reported cases of primary gingival angiosarcomas including the present case.
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Neoplasias Gingivales/patología , Hemangiosarcoma/patología , Neoplasias Maxilares/patología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Gingivales/diagnóstico por imagen , Neoplasias Gingivales/tratamiento farmacológico , Neoplasias Gingivales/cirugía , Hemangiosarcoma/diagnóstico por imagen , Hemangiosarcoma/tratamiento farmacológico , Hemangiosarcoma/cirugía , Humanos , Interleucina-2/uso terapéutico , Masculino , Neoplasias Maxilares/diagnóstico por imagen , Neoplasias Maxilares/tratamiento farmacológico , Neoplasias Maxilares/cirugía , Persona de Mediana Edad , Radiografía , Enfermedades Raras , Proteínas Recombinantes , Resultado del TratamientoRESUMEN
A case of metastatic adenocarcinoma from gastric cancer to the mandibular canine region is reported. Computerized tomography (CT) scanning revealed a small round enhanced inhomogeneous mass, indicating an osteolytic lesion on radiographic classification. Although chemotherapy and radiation therapy was performed, the mass increased, and a subsequent CT scan showed further calcifications within the tumor, indicating progression from an osteolytic to a mixed lesion.
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Adenocarcinoma/secundario , Neoplasias Gingivales/secundario , Neoplasias Mandibulares/secundario , Osteólisis/diagnóstico por imagen , Neoplasias Gástricas/patología , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/terapia , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Diente Canino , Resultado Fatal , Femenino , Neoplasias Gingivales/diagnóstico por imagen , Neoplasias Gingivales/terapia , Humanos , Neoplasias Mandibulares/diagnóstico por imagen , Neoplasias Mandibulares/terapia , Osteólisis/patología , Neoplasias Gástricas/diagnóstico por imagen , Neoplasias Gástricas/terapia , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVES: The aim was to investigate magnetic resonance (MR) and computerized tomography (CT) images and compare MR and CT image features of postoperative maxillary cysts (POMC). STUDY DESIGN: We retrospectively evaluated MR and CT images of 7 POMC patients. Number of the cysts, border, bone expansion, CT value, signal intensity, and contrast enhancement were observed. RESULTS: On CT images, 15 cysts were detected. Fourteen cysts showed smooth border. Bone expansion was found in 10 cysts. Mean CT value of each cyst ranged from 23 to 50 Hounsfield units. On MR images, 18 cysts were detected. Twelve cysts showed smooth border. Bone expansion was not observed. Most cysts showed intermediate signal intensity on T1-weighted images, and high or nonhomogeneous intermediate/high signal intensity on T2-weighted images with the fat suppression technique. No cyst showed contrast enhancement in both examinations. CONCLUSION: The CT images revealed bony information, and the MR images clearly demonstrated border of POMC. POMC should be evaluated with both CT and MR imaging.
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Quistes Maxilomandibulares/diagnóstico , Enfermedades Maxilares/diagnóstico , Complicaciones Posoperatorias/diagnóstico , Adulto , Anciano , Femenino , Humanos , Quistes Maxilomandibulares/patología , Imagen por Resonancia Magnética , Masculino , Enfermedades Maxilares/patología , Seno Maxilar/cirugía , Persona de Mediana Edad , Mucocele/diagnóstico , Mucocele/patología , Estudios Retrospectivos , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Preconditioning with isoflurane has been shown to confer cardioprotection via activation of mitochondrial adenosine triphosphate-sensitive K+ (mito K(ATP)) channels. However, the relative contribution of mito K(ATP) channel and non-mito K(ATP) channel mechanisms to isoflurane-mediated cardioprotection has not been investigated. METHODS: Isolated and buffer-perfused rat hearts were used. Flavoprotein fluorescence was monitored as an index for mito K(ATP) channel activity. Isovolumic left ventricular function and infarct size were measured as indices for cardioprotection. RESULTS: Flavoprotein fluorescence, which was monitored as an index for mito K(ATP) channel activity, was increased by isoflurane and a known mito K(ATP) channel opener, diazoxide, in a 5-hydroxydecanoate-sensitive manner. Although flavoprotein oxidation induced by diazoxide was dissipated soon after its removal from the buffer, flavoprotein oxidation induced by isoflurane was sustained after cessation of the treatment. The sustained increase in flavoprotein oxidation was associated with a significant reduction in infarct size after 30 min of ischemia followed by 120 min of reperfusion. Although adenosine and S-nitroso-N-acetyl-penicillamine each alone did not increase flavoprotein fluorescence, nor did they confer significant cardioprotection, coadministration of adenosine and S-nitroso-N-acetyl-penicillamine with isoflurane conferred a highly significant reduction of infarct size and improvement of left ventricular function without increasing flavoprotein oxidation over isoflurane alone. The early treatment with 5-hydroxydecanoate before and during preconditioning completely reversed flavoprotein oxidation and inhibited the infarct-sparing effect of isoflurane and combined preconditioning with isoflurane, adenosine, and S-nitroso-N-acetyl-penicillamine. The late treatment with 5-hydroxydecanoate after preconditioning abolished flavoprotein oxidation and the infarct-sparing effect of isoflurane but only partially inhibited cardioprotection conferred by the combined preconditioning, despite complete abrogation of flavoprotein oxidation. CONCLUSIONS: Mito K(ATP) channel activation is the essential trigger of both preconditioning with isoflurane and combined preconditioning with isoflurane, adenosine, and S-nitroso-N-acetyl-penicillamine. Mito K(ATP) channel activation is also a crucial mediator of cardioprotection afforded by preconditioning with isoflurane. However, enhanced cardioprotection conferred by combined preconditioning is mediated through both mito K(ATP) channel-dependent and -independent mechanisms.
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Adenosina/farmacología , Anestésicos por Inhalación/farmacología , Fármacos Cardiovasculares/farmacología , Precondicionamiento Isquémico Miocárdico/métodos , Isoflurano/farmacología , Proteínas de la Membrana/fisiología , Mitocondrias Cardíacas/metabolismo , Donantes de Óxido Nítrico/farmacología , Animales , Diazóxido/farmacología , Relación Dosis-Respuesta a Droga , Flavoproteínas/metabolismo , Técnicas In Vitro , Masculino , Proteínas de la Membrana/efectos de los fármacos , Mitocondrias Cardíacas/efectos de los fármacos , Infarto del Miocardio/patología , Infarto del Miocardio/prevención & control , Oxidación-Reducción , Canales de Potasio , Ratas , Ratas Sprague-Dawley , S-Nitroso-N-Acetilpenicilamina/farmacologíaRESUMEN
A relatively high incidence of malignant hyperthermia (MH) and an unpredicted (usually increased) sensitivity to muscle relaxants are reported in patients with congenital myopathies (CM). We present a case of anesthetic management of a patient with a clinical diagnosis of CM. An 18-month-old, 11.3-kg, male patient, who had received a diagnosis of CM, was scheduled for the laparoscopic cryptorchidpexy. Anesthesia was induced with propofol and fentanyl, and the trachea was intubated without muscle relaxants. An epidural catheter was inserted via the sacral hiatus, the tip of which was located at the second lumbar level for a purpose of obtaining not only pain relief but also muscle relaxation. Anesthesia was maintained with propofol, nitrous oxide and fentanyl, combined with epidural anesthesia. The anesthetic course was uneventful with enough pain relief and good muscle relaxation.
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Anestesia Epidural , Anestesia General , Criptorquidismo/cirugía , Laparoscopía , Miopatías Estructurales Congénitas , Humanos , Lactante , Complicaciones Intraoperatorias/prevención & control , Masculino , Hipertermia Maligna/prevención & control , PropofolRESUMEN
1. Activation of mitochondrial KATP (mitoKATP) channels and protein kinase C (PKC) has been implicated in cardioprotective mechanisms of ischaemic preconditioning (IPC). However, the exact role of these events in early IPC remains unclear. 2. Isolated and perfused rat hearts underwent IPC with three cycles of 5 min ischaemia and 5 min reperfusion. The heart was subjected to 30 min global ischaemia followed by 120 min reperfusion. Flavoprotein oxidation was monitored to assess mitoKATP channel activity. Cardioprotection was evaluated by recovery of isovolumic left ventricular (LV) function and infarct size. 3. Diazoxide (50 mgr;mol/L) increased flavoprotein oxidation and conferred cardioprotection in a manner sensitive to the selective mitoKATP channel blocker 5-hydroxydecanoate (5-HD; 0.5 mmol/L). 4. Pretreatment with 0.5 mmol/L 5-HD abrogated IPC-induced flavoprotein oxidation and cardioprotection, whereas late treatment with 5-HD after IPC required a higher dose (2 mmol/L) to abolish flavoprotein oxidation and cardioprotection afforded by IPC. 5. Pretreatment with the PKC inhibitors Ro318425 (1 micro mol/L) and chelerythrine (5 micro mol/L) abolished IPC-induced flavoprotein oxidation and cardioprotection, whereas late treatment with Ro318425 required a higher dose (4 micro mol/L) to abolish flavoprotein oxidation and cardioprotection. 6. In conclusion, these results suggest that activation of mitoKATP channels is the trigger and the mediator of IPC and that PKC plays a crucial role in both phases of mitoKATP channel activation, although mitoKATP channels and PKC may be more activated during the mediator phase.
Asunto(s)
Péptidos y Proteínas de Señalización Intracelular , Canales Iónicos/fisiología , Precondicionamiento Isquémico Miocárdico/métodos , Proteínas de la Membrana/fisiología , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/prevención & control , Proteína Quinasa C/fisiología , Animales , Proteínas Portadoras/farmacología , Proteínas Portadoras/uso terapéutico , Masculino , Canales de Potasio , Proteína Quinasa C/antagonistas & inhibidores , Ratas , Ratas Sprague-Dawley , Función Ventricular Izquierda/efectos de los fármacos , Función Ventricular Izquierda/fisiologíaRESUMEN
BACKGROUND: Mitochondrial K(ATP) channel activation is an essential component of ischemic preconditioning. These channels are selectively opened by diazoxide and may be up-regulated by adenosine and nitric oxide. Therefore, pharmacological preconditioning with diazoxide in combination with adenosine and a nitric oxide donor (triple-combination pharmacological preconditioning) may enhance cardioprotection. METHODS AND RESULTS: Isolated and perfused rat hearts underwent ischemic preconditioning with 3 cycles of 5 minutes of ischemia and 5 minutes of reperfusion before 5 minutes of oxygenated potassium cardioplegia and 35 minutes of ischemia. Pharmacological preconditioning was performed by adding adenosine, diazoxide, and a nitric oxide donor S-nitroso-N-acetyl-penicillamine each alone or in combinations for 25 minutes followed by 10 minutes washout before cardioplegic arrest. Only triple-combination pharmacological preconditioning conferred significant cardioprotection as documented by highly improved left ventricular function and limited creatine kinase release during reperfusion that was comparable to that afforded by ischemic preconditioning. Mitochondrial K(ATP) channel activity assessed by flavoprotein oxidation was increased by diazoxide, but no further increase in flavoprotein oxidation was obtained by ischemic preconditioning and triple-combination pharmacological preconditioning. Significant activation of protein kinase C-epsilon was observed in only ischemic preconditioning and triple-combination pharmacological preconditioning. Pretreatment with the mitochondrial K(ATP) channel inhibitor 5-hydroxydecanoate or the protein kinase C inhibitor chelerythrine abrogated activation of protein kinase C-epsilon and cardioprotection afforded by ischemic preconditioning and triple-combination pharmacological preconditioning. CONCLUSIONS: Integrated pharmacological preconditioning is not simply mediated by enhanced mitochondrial K(ATP) channel activation, but is presumably mediated through amplified protein kinase C signaling promoted by coordinated interaction of adenosine, mitochondrial K(ATP) channel activation, and nitric oxide.