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1.
Clin Radiol ; 75(1): 57-63, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31445764

RESUMO

AIM: To investigate the incidence and clinical characteristics of acute pancreatitis following percutaneous insertion of metallic biliary stents in patients with unresectable pancreatic cancer. The clinical efficacy of metallic stent insertion was also evaluated. MATERIALS AND METHODS: Data from 143 patients (75 men, 68 women; mean age, 65.8 years; range, 35-88 years) with unresectable pancreatic cancer who underwent percutaneous metallic biliary stent insertion between March 2007 and December 2017 were evaluated retrospectively. The incidence and clinical characteristics of acute pancreatitis were analysed. Stent patency and patient survival rates were calculated by Kaplan-Meier analysis. RESULTS: Technical success was achieved in all patients. Among 31 patients with serum amylase levels above normal values (30-110 U/l), only nine had symptoms of acute pancreatitis (incidence, 6.4%). No statistically significant risk factors were identified. Pancreatitis was successfully managed with conservative treatment at a mean of 2.9 days (range, 1-4 days). The median stent patency and patient survival times were 117 days (95% confidence interval [CI], 87-148 days) and 150 days (95% CI, 125-174.9 days), respectively. CONCLUSIONS: Acute pancreatitis was a relatively rare complication after percutaneous insertion of metallic biliary stents in patients with unresectable pancreatic cancer, and no significant risk factors were identified. Therefore, insertion of metallic biliary stents was seen to be a feasible and effective treatment approach in this patient group.


Assuntos
Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/terapia , Pancreatite/prevenção & controle , Stents , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Neoplasias Pancreáticas/mortalidade , Pancreatite/epidemiologia , Pancreatite/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida
2.
Clin Radiol ; 75(2): 158.e1-158.e7, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31711638

RESUMO

AIM: To evaluate the safety and clinical efficacy of interventional treatment for arterial injury during blind, central venous catheterisation in the upper thorax at two tertiary medical centres. MATERIALS AND METHODS: Eighteen consecutive patients (37-81 years; M:F=8:10) who underwent interventional treatment for the arterial injuries that occurred during central venous catheterisation without any imaging guidance between November 2007 and December 2018 were included. Clinical data, angiographic findings, detailed interventional procedures, and technical and clinical outcomes were analysed retrospectively. RESULTS: Arterial injury sites were the subclavian artery/branches (n=12), axillary artery/branches (n=2), and common carotid artery (n=4). The target vein was not correlated with the corresponding artery/branches in eight patients (44.4%); internal jugular vein to subclavian artery branches. Angiographic findings were pseudoaneurysm (66.7%, 12/18), contrast medium extravasation (22.2%, 4/18), or both (11.1%, n=2). A stent graft was inserted for the main trunk injuries in nine patients, with (n=2) or without (n=7) prior arterial branch embolisation to prevent potential endoleak, while embolisation for the arterial branch injuries was performed in nine patients. Direct percutaneous access with thrombin injection to the pseudoaneurysm or residual arteriovenous fistula was utilised in two. The technical and clinical success rate was 94.4% (17/18) each. There were no procedure-related complications. In one patient without immediate clinical success, there was a persistent pseudoaneurysm after stent graft placement, which was treated with in-stent balloon dilation. CONCLUSION: Interventional treatment serves as a safe and effective treatment modality for inadvertent arterial injury related to blind, central venous access catheterisation in the upper thorax.


Assuntos
Angiografia/métodos , Artérias/lesões , Cateterismo Venoso Central/efeitos adversos , Embolização Terapêutica , Adulto , Idoso , Idoso de 80 Anos ou mais , Artéria Axilar/lesões , Lesões das Artérias Carótidas/etiologia , Embolização Terapêutica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Artéria Subclávia/lesões
3.
Clin Radiol ; 70(12): 1388-92, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26382745

RESUMO

AIM: To evaluate safety and clinical outcomes of uterine artery embolisation (UAE) for bleeding after dilatation and curettage (D&C) performed for abortion or termination. MATERIALS AND METHODS: The outcomes were analysed in 11 patients who underwent UAE for bleeding after D&C for missed abortions (n=8), caesarean scar pregnancies (n=2), or planned termination (n=1) between October 2001 and December 2013. Angiograms and medical records were retrospectively reviewed in order to obtain the patients' baseline characteristics, technical/clinical success rate, complications, and follow-up data regarding menstruation. RESULTS: Technical success, defined as successful catheterisation of both uterine arteries with embolisation to haemostasis, was 100%, whereas clinical success, defined as cessation of bleeding after the initial session of UAE and without the need for additional UAE or surgery for the purpose of haemostasis, was 81.8% (nine of 11). In the two patients with clinical failure due to recurrent vaginal bleeding after UAE, one patient underwent repeat UAE and showed a successful outcome, whilst the other patient required hysterectomy with pathological results of placenta increta. Two other patients underwent hysterectomy for placenta percreta or hydatidiform mole-mimicking remnant placenta. None of the patients included in the present series had procedure-related complications. Menstruation resumed in all eight patients with an intact uterus during the mean follow-up period. CONCLUSION: UAE may be a safe and effective treatment for bleeding after D&C, especially for women who wish to preserve their fertility; however, hysterectomy may be indicated for patients with a placental abnormality.


Assuntos
Dilatação e Curetagem/efeitos adversos , Hemorragia Pós-Operatória/etiologia , Hemorragia Pós-Operatória/terapia , Embolização da Artéria Uterina , Aborto Induzido , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Gravidez Ectópica , Estudos Retrospectivos , Resultado do Tratamento
4.
Clin Radiol ; 70(11): 1177-84, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26183132

RESUMO

AIM: To evaluate the efficacy and safety of renal artery embolisation (RAE) for renal arteriovenous malformation (AVM) as well as its outcomes. MATERIALS AND METHODS: The technical and clinical success rates, radiological and laboratory findings, and complications of RAE for 31 renal AVMs in 24 patients (M:F=9:15, mean age 46 years) at two separate medical institutions were retrospectively evaluated. Technical success was defined as complete occlusion of feeding arteries with no residual nidus seen on post-treatment angiography. Clinical failure was defined as recurrence of haematuria, presence of AVM on follow-up ultrasound or computed tomography, repeated RAE or surgery for the control of haematuria. Overall clinical success was defined as resolution haematuria or disappearance of AVM on follow-up imaging after single or multiple sessions of RAE. RESULTS: Types of renal AVM were AVM, arterio-venous fistula (AVF) with intranidal aneurysm, and acquired AVF in 19, 1, and 4 patients, respectively. 18 patients (75%) underwent a single session of RAE, while 6 patients (25%) had two or more sessions of RAE. The level of embolisation was feeder, segmental artery, and main renal artery in 28 (90%), 2 (6%), and 1 (4%) procedures, respectively. Coil, n-butyl 2-cyanoacrylate, and polyvinyl alcohol were the most frequently chosen embolic materials and were used in 19, 14, and 8 procedures, respectively. The clinical success rate after initial RAE was 67% (16/24). Overall clinical success rate, including multisession RAE, was 88% (21/24). The technical success rate of 31 procedures was 65% (20/31). Among 11 technical failures in 10 patients, 4 achieved clinical success without additional RAE, 3 underwent second session RAE to achieve clinical success, and 3 patients underwent nephrectomy due to recurrence. CONCLUSION: RAE is a safe and effective treatment for renal AVM. Technical failure of RAE does not always lead to clinical failure and multiple embolisation sessions may be effective for recurrent renal AVM.


Assuntos
Malformações Arteriovenosas/terapia , Embolização Terapêutica/métodos , Artéria Renal/anormalidades , Veias Renais/anormalidades , Adolescente , Adulto , Idoso , Fístula Arteriovenosa/diagnóstico por imagem , Fístula Arteriovenosa/terapia , Malformações Arteriovenosas/diagnóstico por imagem , Feminino , Dor no Flanco/etiologia , Hematúria/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Artéria Renal/diagnóstico por imagem , Veias Renais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia , Adulto Jovem
5.
Clin Radiol ; 67(4): 359-65, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22142501

RESUMO

AIM: To determine the efficacy of percutaneous transcatheter embolization in the management of patients with spermatic varicocoeles persisting or recurring after surgery. MATERIALS AND METHODS: Over a period of 10 years, 28 patients (age range 13-55 years) were referred for percutaneous transcatheter embolization of postsurgical, recurrent varicocoeles. Medical documents were retrospectively reviewed to evaluate past surgical history, subjective symptoms, and results of scrotal examination, ultrasound, and semen parameters. Pre-embolization venograms were analysed to assess the anatomy of the testicular vein. The technical and clinical outcomes of embolization were then determined. RESULTS: The 28 patients included in the study had undergone laparoscopic varicocoelectomy (39.3%), high retroperitoneal ligation (25%), or inguinal ligation (25%). Subjective symptoms were scrotal pain (60.7%) and a palpable scrotal mass (50%) exclusively on the left side. Venograms revealed abnormalities of the left testicular vein in all cases. Embolization was technically successful in all but two cases, thus yielding an occlusion rate of 93%; a single case of suspected thrombophlebitis was the only complication. After excluding two, technically unsuccessful cases and one patient who was lost to follow-up, 25 patients underwent scrotal examination after embolization, which revealed complete resolution in 20 cases (80%), partial improvement in four cases (16%), and no improvement in a single case (4%). Among the follow-up group of patients, of the 12 who initially presented with scrotal pain, six (50%) were symptom-free and four (33.3%) had partial improvement. CONCLUSION: Percutaneous transcatheter embolization of the testicular vein is technically feasible and effective for managing postsurgical recurrent varicocoeles.


Assuntos
Embolização Terapêutica/métodos , Varicocele/terapia , Adolescente , Adulto , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Flebografia , Recidiva , Estudos Retrospectivos , Testículo/irrigação sanguínea , Resultado do Tratamento , Varicocele/cirurgia
6.
Clin Radiol ; 65(4): 271-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20338393

RESUMO

AIM: To evaluate the safety and efficacy of transcatheter arterial chemo-lipiodol infusion (TACL) in high-risk patients with unresectable hepatocellular carcinoma (HCC). MATERIALS AND METHODS: From January 2005 to April 2009, 96 patients underwent TACL. All patients had diffuse, infiltrative or multifocal tumours. Twenty-nine (30%) patients had an increased serum bilirubin level (>or=2mg/dl), and 75 patients (78%) had a low serum albumin level (<3.5mg/dl). The Child-Pugh (CP) score was 9 or more in 13 (14%) patients. Sixty-five patients (68%) had major portal vein occlusion. Sixteen patients (17%) had biliary dilatation. RESULTS: TACL was technically successful in all patients. After TACL, 18 (19%) of the 96 patients showed tumour response using computed tomography (CT) criteria. The 30 day mortality and morbidity rates were 1 and 2%, respectively. The median survival period was 8.6 months, and the overall 6 month, 1, 2, and 3 year survival rates were 59, 44, 26, and 15%, respectively. Portal vein occlusion (p<0.001) was the only significant risk factor associated with the length of the survival period after TACL, whereas the CP score (p=0.498), serum bilirubin level (p=0.153), serum albumin level (p=0.399), and biliary obstruction (p=0.636) had no significant effect. CONCLUSIONS: TACL can be performed safely in high risk HCC patients resulting in a median survival rate of 8.6 months in the present series.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Meios de Contraste/uso terapêutico , Óleo Iodado/uso terapêutico , Neoplasias Hepáticas/terapia , Adulto , Idoso , Bilirrubina/sangue , Carcinoma Hepatocelular/mortalidade , Quimioembolização Terapêutica/efeitos adversos , Quimioembolização Terapêutica/mortalidade , Feminino , Humanos , Infusões Intra-Arteriais , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Albumina Sérica/química , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Resultado do Tratamento
7.
Clin Radiol ; 65(4): 288-96, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20338395

RESUMO

AIM: To evaluate liver volume alterations and liver function after right portal vein embolization (PVE) during mid-term follow-up based on embolization score. MATERIALS AND METHODS: Computed tomography (CT) images and liver function profiles were obtained before PVE, and at short-term (7-45 days), and mid-term follow-up (106-380 days) after PVE in all 30 patients. The patients were divided into group A (PVE score >or=3, n=20) and group B (PVE score <3, n=10). High score indicates more complete embolization. RESULTS: Left liver volume (LLV) and percentage future liver remnant (%FLR) increased significantly between pre-PVE and short-term follow-up and between short-term and mid-term follow-up in group A. Increase in FLR volume was significantly higher at the mid-term follow-up than at the short-term follow-up in group A. The ratio of embolized to total liver volume (RETLV) on short-term follow-up was significantly higher in group A than in group B. Aspartate transaminase (AST) and alanine transaminase (ALT) were elevated on short-term follow-up, whereas at mid-term follow-up in group A, they had significantly returned to the baselines. CONCLUSION: PVE resulted in continued compensatory hypertrophy of the unembolized liver during the 6-month follow-up. Compensatory hypertrophy in the unembolized liver was proportional to the ratio of embolization and to the embolized liver volume.


Assuntos
Embolização Terapêutica/métodos , Hepatopatias/terapia , Fígado/diagnóstico por imagem , Veia Porta/diagnóstico por imagem , Adulto , Idoso , Alanina Transaminase/metabolismo , Aspartato Aminotransferases/metabolismo , Feminino , Esponja de Gelatina Absorvível/uso terapêutico , Humanos , Hipertrofia/diagnóstico por imagem , Hipertrofia/patologia , Fígado/irrigação sanguínea , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Cuidados Pré-Operatórios/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
8.
Br J Surg ; 96(7): 720-3, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19526615

RESUMO

BACKGROUND: Spontaneous isolated dissection of the superior mesenteric artery (SMA) is uncommon. Because of its rarity, the risk factors, aetiology and natural history are unclear, and there is no consensus on the optimal treatment strategy. METHODS: Seven consecutive patients with symptomatic spontaneous isolated SMA dissection who received conservative treatment between March 2003 and February 2008 were included in this study. Their clinical characteristics, treatment methods and outcomes were analysed retrospectively. RESULTS: Acute abdominal pain was the most common clinical manifestation. Initial contrast-enhanced dynamic computed tomography (CT) showed isolated SMA dissection with partial thrombosis in all seven patients. Full anticoagulation was carried out immediately after the diagnosis. Clinical symptoms disappeared within 14 days and follow-up CT showed complete resolution of the dissection in four patients. After a mean follow-up of 23 months, there was no mortality or morbidity related to the dissection. CONCLUSION: In patients with symptomatic spontaneous isolated dissection of the SMA, conservative management is feasible if there is no evidence of bowel infarction or bleeding.


Assuntos
Anticoagulantes/uso terapêutico , Oclusão Vascular Mesentérica/tratamento farmacológico , Trombose/tratamento farmacológico , Tomografia Computadorizada por Raios X , Dor Abdominal/etiologia , Adulto , Feminino , Humanos , Masculino , Artéria Mesentérica Superior/diagnóstico por imagem , Oclusão Vascular Mesentérica/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Trombose/diagnóstico por imagem , Resultado do Tratamento
9.
Clin Radiol ; 64(8): 779-85, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19589416

RESUMO

AIM: To describe the image findings and results of transcatheter arterial chemoembolization (TACE) or transcatheter arterial embolization (TAE) for treating primary hepatic angiosarcoma. MATERIALS AND METHODS: A retrospective review of the electronic medical database from 2002 to 2007, revealed six patients with primary hepatic angiosarcoma confirmed by percutaneous liver biopsy. The computed tomography (CT) and angiography imaging findings, the TACE or TAE results, and the post-procedure course were evaluated in all patients. RESULTS: On CT and angiography, each tumour appeared as a solitary mass or as multiple nodules or masses with heterogeneously early and progressive enhancement. One of the two patients with tumour response to TACE died 8 months after initial presentation, and the remaining patient was still alive at the last follow-up 12 months after initial presentation. However, two patients with no response to TACE and two patients who underwent emergent TAE for tumour rupture died 1 week to 5 months (mean 2.1 months) after initial presentation. CONCLUSIONS: Primary hepatic angiosarcoma appears as a solitary or multiple, hypervascular lesions with heterogeneously early and progressive enhancement on CT and angiography. Although TAE may be the primary procedure for achieving emergent bleeding control caused by the rupture of hepatic angiosarcomas, TACE may be effective for treating patients with a dominant hepatic angiosarcoma with or without intrahepatic metastases.


Assuntos
Hemangiossarcoma/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia/métodos , Antineoplásicos/administração & dosagem , Quimioembolização Terapêutica/métodos , Cisplatino/administração & dosagem , Embolização Terapêutica/métodos , Evolução Fatal , Feminino , Hemangiossarcoma/irrigação sanguínea , Hemangiossarcoma/patologia , Hemangiossarcoma/terapia , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos/métodos , Radiografia Intervencionista , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
10.
Diagn Interv Imaging ; 100(6): 337-345, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30691971

RESUMO

PURPOSE: This study aimed to evaluate the safety and effectiveness of interventional techniques as a treatment for bleeding complications secondary to percutaneous cannulation for peripheral extracorporeal membrane oxygenation (PECMO). MATERIALS AND METHODS: Out of 1264 patients who underwent PECMO at our hospital between January 2009 and September 2018, we reviewed the clinical characteristics and outcomes of eight patients (4 men, 4 women; mean age, 54.9 years [range, 31-77 years]) who underwent percutaneous interventional treatment for bleeding complications secondary to percutaneous cannulation for PECMO. RESULTS: Both hemodynamic instability and coagulopathy were present in 7 patients who had direct injury during PECMO insertion and absent in one patient with pseudoaneurysm at the PECMO removal site. Percutaneous ultrasound-guided thrombin injection was performed in three patients with pseudoaneurysm of the common or superficial femoral artery, and adjunctive embolization was combined with microcoils or n-butyl 2-cyanoacrylate in two of them. Stent graft was inserted in four patients with contrast extravasation (n=3) from external iliac artery (n=1) or common femoral or iliac veins (n=2) ruptures or the fistula between the superficial femoral artery and vein (n=1). N-butyl 2-cyanoacrylate and coil embolization was performed for pseudoaneurysm from the internal pudendal artery branch in the remaining one patient. Technical success was achieved in all eight patients. There were no procedure-related complications. There was no rebleeding during the follow-up. CONCLUSION: Interventional treatment is a safe, technically feasible and therapeutically effective modality for treating bleeding complications secondary to a percutaneous cannulation for PECMO.


Assuntos
Cateterismo/efeitos adversos , Oxigenação por Membrana Extracorpórea/métodos , Hemorragia/etiologia , Hemorragia/terapia , Adulto , Idoso , Cateterismo/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Neuron ; 29(1): 255-66, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11182096

RESUMO

cGMP-gated channels are essential for phototransduction in the vertebrate retina. Here we show that the affinity of these channels for cGMP in chick cones is substantially higher during the subjective night than during the subjective day. This effect persists in constant environmental conditions after entrainment to 12:12 hr light-dark cycles in vitro or in ovo. Circadian modulation of ligand affinity is a posttranslational effect and is driven by rhythms in the activities of two protein kinases: Erk and Ca2+/calmodulin-dependent protein kinase II (CaMKII). Erk is maximally active during the subjective night, whereas CaMKII is maximally active during the subjective day. Acute inhibition of these signaling pathways causes phase-dependent changes in the affinity of the channels for cGMP.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Ritmo Circadiano/fisiologia , Canais Iônicos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Animais , Relógios Biológicos/fisiologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Células Cultivadas , Embrião de Galinha , GMP Cíclico/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos , Escuridão , Inibidores Enzimáticos/farmacologia , Proteínas do Olho/metabolismo , Ativação do Canal Iônico/fisiologia , Ligantes , Luz , MAP Quinase Quinase 1 , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Técnicas de Patch-Clamp , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Células Fotorreceptoras Retinianas Cones/citologia , Transdução de Sinais
12.
J Neurosci ; 19(16): 6784-94, 1999 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10436036

RESUMO

Postsynaptic injection of Ca(2+)/calmodulin (Ca(2+)/CaM) into hippocampal CA1 pyramidal neurons induces synaptic potentiation, which can occlude tetanus-induced potentiation (Wang and Kelly, 1995). Because Ca(2+)/CaM activates the major forms of nitric oxide synthase (NOS) to produce nitric oxide (NO), NO may play a role during Ca(2+)/CaM-induced potentiation. Here we show that extracellular application of the NOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) or postsynaptic co-injection of L-NAME with Ca(2+)/CaM blocked Ca(2+)/CaM-induced synaptic potentiation. Thus, NO is necessary for Ca(2+)/CaM-induced synaptic potentiation. In contrast, extracellular perfusion of membrane-impermeable NO scavengers N-methyl-D-glucamine dithiocarbamate/ferrous sulfate mixture (MGD-Fe) or 2-(4-carboxyphenyl)-4,4,5, 5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO) did not attenuate Ca(2+)/CaM-induced synaptic potentiation, even though MGD-Fe or carboxy-PTIO blocked tetanus-induced synaptic potentiation. This result indicates that NO is not a retrograde messenger in Ca(2+)/CaM-induced synaptic potentiation. However, postsynaptic co-injection of carboxy-PTIO with Ca(2+)/CaM blocked Ca(2+)/CaM-induced potentiation. Postsynaptic injection of carboxy-PTIO alone blocked tetanus-induced synaptic potentiation without affecting basal synaptic transmission. Our results suggest that NO works as a postsynaptic (intracellular) messenger during Ca(2+)/CaM-induced synaptic potentiation.


Assuntos
Cálcio/farmacologia , Calmodulina/farmacologia , Potenciação de Longa Duração/fisiologia , Óxido Nítrico/fisiologia , Células Piramidais/fisiologia , Transdução de Sinais/fisiologia , Animais , Inibidores Enzimáticos/farmacologia , Feminino , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Células Piramidais/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Sinapses/fisiologia
13.
J Neurosci ; 21(1): 221-9, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11150339

RESUMO

The cyclic GMP-gated cationic channels of vertebrate photoreceptors are essential for visual phototransduction. We have examined the developmental regulation of cGMP-gated channels in morphologically identified cones in the chick retina. Expression of cone-type cGMP-gated channel mRNA can be detected at embryonic day 6 (E6), but expression of functional channels, as accessed by patch-clamp recordings, cannot be detected until E8. Plasma membrane channels in embryonic cones have a high turnover rate because inhibition of protein synthesis or disruption of the Golgi apparatus causes an almost complete loss of functional cGMP-gated channels within 12 hr. Different subpopulations of cones begin to express functional channels at different developmental stages, but all cones express channels by E10. Expression of cGMP-gated channels in at least one cone subpopulation appears to require one or more soluble differentiation factors, which are presumably present in the normal microenvironment of the developing retina. Application of chick embryo extract (CEE), a rich source of trophic factors, causes marked stimulation of cGMP-gated channel expression in chick cones at E8, but not at E6. Inhibition of MAP kinase (Erk) signaling using PD98059, or inhibition of PI3 kinase signaling by LY294002, blocked the stimulatory effects of CEE on E8 cones. Several recombinant trophic factors were also tested, but none could mimic the stimulatory effects of CEE on channel expression. In summary, the developmental expression of cGMP-gated cationic channels in embryonic cones appears to be regulated by epigenetic factors. The ability of cones to respond to these epigenetic factors is also developmentally regulated.


Assuntos
GMP Cíclico/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Canais Iônicos/biossíntese , Retina/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Extratos Celulares/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Cromonas/farmacologia , GMP Cíclico/antagonistas & inibidores , GMP Cíclico/farmacologia , Canais de Cátion Regulados por Nucleotídeos Cíclicos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Ativação do Canal Iônico/efeitos dos fármacos , Canais Iônicos/genética , Sistema de Sinalização das MAP Quinases , Morfolinas/farmacologia , Técnicas de Patch-Clamp , Inibidores de Fosfoinositídeo-3 Quinase , RNA Mensageiro/biossíntese , Retina/efeitos dos fármacos , Retina/embriologia , Células Fotorreceptoras Retinianas Cones/efeitos dos fármacos
14.
Poult Sci ; 84(11): 1791-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16463979

RESUMO

Shell eggs were irradiated and the physico-chemical, and functional properties of egg yolk and white were determined. The color of egg yolk was not affected, but the viscosity of egg white was dramatically lowered and became watery by irradiation. The foam capacity and foam stability of egg white were significantly decreased due to protein oxidation by irradiation. However, the texture characteristics of egg white were not changed by irradiation, indicating that irradiation may not alter the thermal characteristics of egg white proteins. Sulfur volatiles were generated by irradiation but disappeared during storage under aerobic conditions. Because egg white became watery, irradiation may not be advisable for table eggs but may be useful for pasteurizing liquid egg white or liquid whole egg without significant deterioration of their quality and functionality. In particular, the dramatic decrease in the viscosity of egg white by irradiation will improve flow of liquid egg white or liquid whole egg, which could be highly useful for egg processing.


Assuntos
Galinhas , Clara de Ovo/efeitos da radiação , Gema de Ovo/efeitos da radiação , Ovos/efeitos da radiação , Manipulação de Alimentos/métodos , Animais , Relação Dose-Resposta à Radiação , Gema de Ovo/química
15.
Brain Res Bull ; 42(4): 297-302, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9043716

RESUMO

The effects of phenobarbital, phenytoin, and valproic acid on pharmacologically isolated NMDA-EPSP, AMPA-EPSP, and GABA-IPSPs were examined in rat hippocampal slices. Phenobarbital (0.05 mg/ml) had no effect on the NMDA-EPSP, but decreased the slope of the AMPA-EPSP by 13.4% and facilitated the GABA-IPSP slope by 77.12%. Phenytoin (0.02 mg/ml) had no effects on the NMDA-EPSP, AMPA-EPSP, or GABA-IPSP. Valproic acid (0.1 mg/ml) decreased the NMDA-EPSP slope by 14.3%, increased the GABA-IPSP slope by 54.34%, and had no effect on the AMPA-EPSP. These data suggest that the mechanisms of action of these anticonvulsant drugs may be via their actions on different neurotransmitter systems or ion channels.


Assuntos
Anticonvulsivantes/farmacologia , Hipocampo/efeitos dos fármacos , N-Metilaspartato/farmacologia , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/farmacologia , Ácido gama-Aminobutírico/farmacologia , Animais , Eletrofisiologia , Hipocampo/fisiologia , Masculino , Fenobarbital/farmacologia , Fenitoína/farmacologia , Ratos , Ratos Endogâmicos , Ácido Valproico/farmacologia
16.
J Clin Neurophysiol ; 14(4): 264-93, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9337139

RESUMO

Discoveries made during the past decade have greatly improved our understanding of how the nervous system functions. This review article examines the relation between memory and the cellular mechanisms of neuronal and synaptic plasticity in the central nervous system. Evidence indicating that activity-dependent short- and long-term changes in strength of synaptic transmission are important for memory processes is examined. Focus is placed on one model of synaptic plasticity called long-term potentiation, and its similarities with memory processes are illustrated. Recent studies show that the regulation of synaptic strength is bidirectional (e.g., synaptic potentiation or depression). Mechanisms involving intracellular signaling pathways that regulate synaptic strength are described, and the specific roles of calcium, protein kinases, protein phosphatases, and retrograde messengers are emphasized. Evidence suggests that changes in synaptic ultrastructure, dendritic ultrastructure, and neuronal gene expression may also contribute to mechanisms of synaptic plasticity. Also discussed are recent findings about postsynaptic mechanisms that regulate short-term synaptic facilitation and neuronal burst-pattern activity, as well as evidence about the subcellular location (presynaptic or postsynaptic) of mechanisms involved in long-term synaptic plasticity.


Assuntos
Hipocampo , Memória/fisiologia , Plasticidade Neuronal/fisiologia , Sinapses/fisiologia , Transmissão Sináptica , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Cálcio/fisiologia , Canais de Cálcio/química , Canais de Cálcio/fisiologia , Hipocampo/anatomia & histologia , Hipocampo/fisiologia , Humanos , Aprendizagem/fisiologia , Potenciação de Longa Duração/fisiologia , Memória/efeitos dos fármacos , Modelos Biológicos , Óxido Nítrico/fisiologia , Via Perfurante/anatomia & histologia , Via Perfurante/fisiologia , Fosfoproteínas Fosfatases/fisiologia , Proteínas Quinases/fisiologia , Sinapses/química
17.
Br J Radiol ; 73(876): 1270-4, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11205670

RESUMO

The purpose was to evaluate angiographic and CT manifestations of vascular Behçet's disease. The medical records of 64 patients with Behçet's disease, treated in our hospital during the last 4 years, were reviewed. 37 patients underwent angiography or CT in the symptomatic regions because of symptoms or clinical signs of vascular involvement by Behçet's disease. 33 (male:female ratio 28:5; mean age 35 years) of the 37 patients demonstrated vascular involvement, which was surgically proven (18 patients) or diagnosed on angiography (15 patients). Angiograms and CT images of these 33 patients were retrospectively analysed for lesion type, location, extent and other characteristic findings of vascular involvement. 12 patients had only venous lesions, 11 had only arterial lesions and 10 had both arterial and venous lesions. The major angiographic findings of vascular Behçet's disease were acute or chronic thrombosis in deep veins of the lower extremities (19 patients), in the inferior vena cava (4 patients) and in the superior vena cava (2 patients), pseudoaneurysms of large or medium sized arteries (11 patients), and occlusions/ stenoses of distal run-off arteries (13 patients). Common CT findings were obliterated deep veins (8 patients) and non-calcified thickened aneurysmal walls (9 patients), with or without contrast enhancement. The combination of these angiographic and CT findings with clinical manifestations are helpful in distinguishing vascular Behçet's disease from other vasculitides.


Assuntos
Arteriopatias Oclusivas/diagnóstico por imagem , Síndrome de Behçet/diagnóstico por imagem , Trombose Venosa/diagnóstico por imagem , Doença Aguda , Adulto , Falso Aneurisma/diagnóstico por imagem , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Arteriopatias Oclusivas/etiologia , Síndrome de Behçet/complicações , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Trombose Venosa/etiologia
18.
Br J Radiol ; 87(1041): 20140054, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24970695

RESUMO

OBJECTIVE: To evaluate the overall and cumulative incidence, degree, interval change and predictors of hepatic arterial injury (HAI) after cisplatin and Gelfoam® (Upjohn, Kalamazoo, MI)-based transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). METHODS: A total of 205 patients with HCC who underwent three or more sessions of TACE without additional surgical or local treatment were included. HAI was evaluated at each segment of the hepatic artery using a three-grade scale: 1 (slight wall irregularity), 2 (overt stenosis) and 3 (occlusion). HAI interval change was categorized into three groups: progression, stable state and improvement. Cumulative incidence of HAI was analysed using Kaplan- Meier method, and predictors of HAI (patient age, sex, portal vein thrombosis and Child-Pugh classification) were analysed by univariate logistic regression. RESULTS: HAI occurred in 50 of the 205 study patients (24.4%). The cumulative incidence of HAI was 16.0% [95% confidence interval (CI), 10.21-21.77] during 5 sessions of TACE, 52.1% (95% CI, 37.83-66.29) during 10 sessions and 68.0% (95% CI, 67.62-88.46) during 15 sessions. Initial HAI was interpreted as grades 1, 2 and 3 in 11 (22.0%), 17 (34.0%) and 22 (44.0%) patients, respectively. When the interval change was assessed in 48 patients with available follow-up TACE, 40 (83.3%) were included in the progression, 2 (4.2%) in the stable state and 6 (12.5%) in the improvement groups. The univariate analysis used to determine the predictors of HAI revealed no significant predictors. CONCLUSION: In three or more sessions of TACE, the incidence of HAI was 24%. Increasing TACE causes increased incidence of HAI. The initial presentation was most commonly grade 3, and 12.5% of the patients with HAI showed improvement of the HAI grade during follow-up TACE. ADVANCES IN KNOWLEDGE: In patients who underwent three or more sessions of cisplatin and Gelfoam-based TACE, the overall incidence of HAI was 24.4%, and increasing TACE causes increased incidence of HAI.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/efeitos adversos , Artéria Hepática/diagnóstico por imagem , Artéria Hepática/lesões , Neoplasias Hepáticas/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia , Carcinoma Hepatocelular/diagnóstico por imagem , Quimioembolização Terapêutica/métodos , Cisplatino/administração & dosagem , Feminino , Seguimentos , Esponja de Gelatina Absorvível/administração & dosagem , Hemostáticos/administração & dosagem , Humanos , Incidência , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida , Trombose Venosa/diagnóstico por imagem , Adulto Jovem
19.
Transplant Proc ; 44(3): 765-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22483490

RESUMO

PURPOSE: To assess the incidence and management of postoperative abdominal bleeding after orthotopic liver transplantation (OLT) and to identify risk factors for abdominal bleeding. METHODS: We retrospectively reviewed the medical records of 1039 patients who underwent OLT at our institution from January 2008 to December 2010 seeking to identify subjects with posttransplantation abdominal bleeding, defined as any hemorrhage requiring radiologic intervention or laparotomy within the first month. RESULTS: Among the 1039 patients, 94 (9%) showed abdominal bleeding, occurring at a mean of 6.1 days (range, day 1 to 21 days). Active bleeding was controlled by endovascular interventional techniques (n = 37; 39%), by surgical ligation or vascular reconstruction (n = 43; 46%), or by sequential combinations of endovascular intervention and surgery (n = 14; 15%). The most frequent bleeding sites for radiologic intervention were the right inferior phrenic artery (n = 14), right and left epigastric arteries (n = 7), intercostal artery (n = 5) and right renal capsular artery (n = 4). The most frequent bleeding sites requiring laparotomy were the hepatic artery (n = 9), diaphragm (n = 8), inferior vena cava (n = 5), abdominal drain insertion site (n = 4), portal vein anastomosis site (n = 4), abdominal wall (n = 3), liver graft cut surface (n = 3), hilar plate (n = 3), and greater omentum (n = 3). Bleeding episodes were associated with greater patient age and increased intraoperative blood loss. CONCLUSIONS: The risk of bleeding from coagulopathy and iatrogenic injury is high during the early posttransplantation period. This risk of bleeding can be minimized by meticulous surgical dissection and bleeding control.


Assuntos
Abdome , Transplante de Fígado , Hemorragia Pós-Operatória/terapia , Adulto , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Hemorragia Pós-Operatória/complicações
20.
Transplant Proc ; 43(5): 1790-3, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21693280

RESUMO

PURPOSE: To estimate the effect of splenic artery embolization (SAE) on blood flow in orthotopic liver transplantation (OLT) recipients with splenic artery steal syndrome (SASS) based on changes in caliber of related arteries upon serial computed tomography (CT) scans. METHODS: Between 2004 and 2007, nine OLT recipients with SASS underwent SAE. They had CT scans before and after SAE: short-, mid-, and long-term, ie, approximately 1 week, 1 month, and 1 year, respectively. The diameters of the celiac axis (CA), common hepatic artery (CHA), and splenic artery (SA) were measured with arterial phase of each CT scan and the ratios of SA to CHA diameter (SA/CHA) calculated to analyze their changes during the follow-up period. RESULTS: The diameters of celiac axis, CHA, and SA and SA/CHA changed most rapidly during the short-term period. The CHA diameter significantly increased short-term post-SAE by CT and slightly decreased thereafter. However, the mid-term and long-term post-SAE CT values were still significantly greater than those on the pre-SAE CT. The SA diameter steadily decreased throughout the follow-up. The SA/CHA decreased until the mid-term. The SA diameter and SA/CHA were significantly smaller upon mid-term and long-term post-SAE CT compared with those at pre-SAE CT. CONCLUSIONS: The effect of SAE to improve hepatic arterial flow in OLT recipients with SASS might be expected for at least approximately one year. The effect maximally occurred during the short-term after SAE on the basis of changes in the caliber of related arteries upon CT.


Assuntos
Arteriopatias Oclusivas/terapia , Oclusão com Balão , Transplante de Fígado/efeitos adversos , Artéria Esplênica/patologia , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/etiologia , Feminino , Humanos , Doadores Vivos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
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