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1.
Spine Surg Relat Res ; 8(2): 212-217, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38618220

RESUMO

Introduction: The advancement of surgical techniques and perioperative management for congenital heart disease (CHD) has increased life expectancy. The surgical creation of the Fontan circulation maintains pulmonary blood flow without relying on an effective pump from the abnormal heart, relying on peripheral vascular resistance to maintain effective flow through the lungs. Unfortunately, this delicate mechanism is compromised when scoliosis restricts ventilation, leading to Fontan failure and a poor prognosis for life. This report describes the prevalence of scoliosis with Fontan completion surgery and the role of screening and surgical correction. Methods: Ninety-six consecutive Japanese patients undergoing Fontan completion surgery for CHD between 2000 and 2017 were identified in our institutional records. The inclusion criterion was at least 7 years of follow-up after Fontan completion surgery, while the exclusion criteria were congenital, syndromic, and neuromuscular scoliosis. Radiographic and clinical parameters, including cardio-thoracic ratio (CTR) for cardiomegaly and cyanosis saturation, were compared between with and without scoliosis. Results: There were 23 and 40 patients in the scoliosis and no scoliosis groups, respectively. The mean age at the final follow-up was 18.5 and 16.7 years in the scoliosis and no scoliosis groups, respectively (p=0.02). Mean CTR was 43.7% and 39.4% in the scoliosis and no scoliosis groups (p=0.016), and the mean saturation in room air at the final follow-up was 88.8% and 93.2%, respectively (p=0.036). There were no significant differences to clarify the risk factors with multivariate logistic regression analysis. Conclusions: The prevalence of scoliosis with Fontan completion surgery was 36.5%. Screening for scoliosis is important for children with Fontan circulation surgery as part of their routine follow-up at least until they reach adolescence.Evidence Level: 4.

2.
J Cataract Refract Surg ; 50(7): 707-712, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38517986

RESUMO

PURPOSE: To investigate the long-term outcomes of congenital cataract surgery performed within the first 6 months of life. SETTING: 11 ophthalmic surgical sites in Japan. DESIGN: Retrospective chart review. METHODS: Medical charts were retrospectively reviewed for 216 eyes of 121 patients. The age at surgery was 2.9 ± 1.7 months, with follow-up duration 13.0 ± 2.3 years. The cohort consisted of 83 cases with bilateral aphakia, 12 with bilateral pseudophakia, 20 with unilateral aphakia, and 6 with unilateral pseudophakia. RESULTS: Surgical intervention within the critical period of visual system development (10 weeks for bilateral and 6 weeks for unilateral cases) led to significantly better final visual acuity than surgery conducted after this time frame. The incidence of secondary glaucoma was similar between groups while the occurrence of visual axis opacification was more frequent with earlier surgery. A forward stepwise multiple regression analysis revealed that the final visual acuity was significantly associated with laterality of cataract (better outcomes in bilateral cases), phakic status (with pseudophakia outperforming aphakia), presence of systemic and ocular comorbidities, and development of secondary glaucoma. Secondary glaucoma was significantly more prevalent in aphakic eyes than pseudophakic eyes. CONCLUSIONS: In patients with genuine congenital cataract, surgery within the critical period of visual development results in better final visual acuity, albeit with an increased risk of visual axis opacification. The use of IOL with sophisticated surgical techniques shows promise even in congenital cataract surgery.


Assuntos
Afacia Pós-Catarata , Extração de Catarata , Catarata , Implante de Lente Intraocular , Pseudofacia , Acuidade Visual , Humanos , Acuidade Visual/fisiologia , Estudos Retrospectivos , Catarata/congênito , Catarata/complicações , Lactente , Masculino , Feminino , Pseudofacia/fisiopatologia , Seguimentos , Afacia Pós-Catarata/fisiopatologia , Afacia Pós-Catarata/cirurgia , Resultado do Tratamento , Recém-Nascido , Glaucoma/cirurgia , Glaucoma/fisiopatologia , Glaucoma/congênito
3.
Sci Rep ; 13(1): 21645, 2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38062153

RESUMO

We assessed the 10-year postoperative outcomes of pediatric cataract patients who underwent surgery at the age of 6 years or younger. A retrospective review of medical charts was conducted for 457 eyes of 277 patients, with the age at surgery averaging 1.3 ± 1.5 years (mean ± SD) and the follow-up duration averaging 12.8 ± 2.4 years (ranging from 10 to 17 years). The cohort included 250 eyes of 125 cases with bilateral aphakia (age at surgery 0.5 ± 0.8 years), 110 eyes of 55 cases with bilateral pseudophakia (1.9 ± 1.6 years), 42 cases with unilateral aphakia (1.1 ± 1.3 years), and 55 cases with unilateral pseudophakia (2.6 ± 1.7). A forward stepwise multiple regression analysis revealed that the best-corrected visual acuity at the final visit was significantly associated with laterality of cataract (with bilateral cases showing better results compared to unilateral cases), presence of systemic comorbidities, presence of ocular comorbidities, development of glaucoma, and phakic status (with better results in the pseudophakia group than the aphakia group). The age at surgery did not significantly affect visual acuity outcomes. A multiple logistic regression analysis demonstrated that the incidence of secondary glaucoma was significantly linked to younger age at surgery, phakic status (higher in aphakic than pseudophakic eyes), and presence of systemic comorbidities. In conclusion, after pediatric cataract surgery, final visual acuity was better in patients with bilateral cataracts, those treated with an intraocular lens, and cases without systemic or ocular comorbidities and secondary glaucoma. The development of secondary glaucoma was linked to younger age at surgery, aphakic status, and presence of systemic comorbidities.


Assuntos
Afacia Pós-Catarata , Extração de Catarata , Catarata , Glaucoma , Humanos , Criança , Lactente , Pseudofacia , Implante de Lente Intraocular/efeitos adversos , Prognóstico , Afacia Pós-Catarata/complicações , Seguimentos , Extração de Catarata/métodos , Catarata/epidemiologia , Catarata/complicações , Glaucoma/complicações , Estudos Retrospectivos , Análise Multivariada , Resultado do Tratamento
4.
Front Cardiovasc Med ; 10: 1212882, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37731527

RESUMO

Aims: Limited data exist on risk factors for the long-term outcome of pulmonary arterial hypertension (PAH) associated with congenital heart disease (CHD-PAH). We focused on the index of pulmonary vascular disease (IPVD), an assessment system for pulmonary artery pathology specimens. The IPVD classifies pulmonary vascular lesions into four categories based on severity: (1) no intimal thickening, (2) cellular thickening of the intima, (3) fibrous thickening of the intima, and (4) destruction of the tunica media, with the overall grade expressed as an additive mean of these scores. This study aimed to investigate the relationship between IPVD and the long-term outcome of CHD-PAH. Methods: This retrospective study examined lung pathology images of 764 patients with CHD-PAH aged <20 years whose lung specimens were submitted to the Japanese Research Institute of Pulmonary Vasculature for pulmonary pathological review between 2001 and 2020. Clinical information was collected retrospectively by each attending physician. The primary endpoint was cardiovascular death. Results: The 5-year, 10-year, 15-year, and 20-year cardiovascular death-free survival rates for all patients were 92.0%, 90.4%, 87.3%, and 86.1%, respectively. The group with an IPVD of ≥2.0 had significantly poorer survival than the group with an IPVD <2.0 (P = .037). The Cox proportional hazards model adjusted for the presence of congenital anomaly syndromes associated with pulmonary hypertension, and age at lung biopsy showed similar results (hazard ratio 4.46; 95% confidence interval: 1.45-13.73; P = .009). Conclusions: The IPVD scoring system is useful for predicting the long-term outcome of CHD-PAH. For patients with an IPVD of ≥2.0, treatment strategies, including choosing palliative procedures such as pulmonary artery banding to restrict pulmonary blood flow and postponement of intracardiac repair, should be more carefully considered.

5.
J Clin Ultrasound ; 51(6): 1003-1014, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37262363

RESUMO

OBJECTIVES: To demonstrate the association between the dynamic movements of hyperechoic foci in portal venous gas (PVG) and patients'/sonographic outcomes after congenital heart disease or cardiac events. METHODS: Thirty-one pediatric patients requiring management of congenital heart diseases or cardiac events who had PVG on ultrasound were included in this retrospective study. The patient outcome was prognosis: dead or alive. The sonographic outcome was recovery from PVG, measured as days from PVG detection to when it diminished on ultrasound. The following sonographic findings of hyperechoic foci in PVG were compared between patients: detection within the mesenteric vein, having to-and-fro movements within the intrahepatic portal vein, distribution (left segment or both left and right segments) and shape (line or punctate) in the liver, and detection within the portal and hepatic veins. Comparisons were made using Fisher's exact/Mann-Whitney U test. RESULTS: Four patients died without having recovered from PVG. A significant difference was observed in terms of the to-and-fro movement (with/without to-and-fro movement in dead vs. alive patients: 3/1 vs. 1/26, respectively; P = 0.003). Furthermore, a significant difference in sonographic outcomes was observed regarding patients with/without hyperechoic foci within the mesenteric vein (days with vs. without this finding: 2.0 ± 1.24(1-5) vs.1 ± 0(1), respectively; P = 0.011). CONCLUSIONS: In our small limited cohort, when PVG was visualized on ultrasound, close evaluation of the dynamic movement of hyperechoic foci, especially their to-and-fro movement within the intrahepatic portal vein and detection of hyperechoic foci within the mesenteric vein, were useful in predicting patients' outcomes and the time to PVG diminishment.


Assuntos
Doenças Cardiovasculares , Veia Porta , Humanos , Criança , Veia Porta/diagnóstico por imagem , Estudos Retrospectivos , Fígado , Abdome
6.
J Card Surg ; 36(11): 4007-4014, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34365671

RESUMO

BACKGROUND: Mortality rates after the arterial switch operation (ASO) for transposition of the great arteries (TGA) are still suboptimal mainly due to postoperative myocardial ischemia. The present study aimed to investigate the clinical impact of our modification of coronary transfer technique, wherein the coronary cuffs are transferred oblique to the pulmonary trunk to avoid torsion of the coronary arteries. METHODS: From September 2010 to August 2020, all 37 consecutive patients who underwent ASO for TGA with our modification, that is, the oblique coronary transfer technique, were retrospectively reviewed. Cardiac dimensions and patency of the coronary arteries were examined by cineangiography, and hemodynamic parameters were measured by cardiac catheterization and transthoracic echocardiography. RESULTS: During a median 5.3 years of postoperative follow-up, there were no deaths and no patient required mechanical circulatory support. Median left ventricular ejection fraction was 68.8% (interquartile range 66.8-71.0, minimum 54.6). All patients maintained normal sinus rhythm without arrhythmia, except in the early postoperative period. Five patients underwent unplanned re-intervention for peripheral pulmonary stenosis, but none for coronary insufficiency. The 8-year freedom from re-intervention rate was 85.6%. Among a total of 110 transplanted coronary arteries, 108 (98.2%) remained patent, and two circumflex arteries were occluded much later after surgery, although with preserved ventricular function due to compensatory growth of other coronary branches. CONCLUSION: The oblique coronary transfer technique, which aims to avoid torsion of the coronary arteries, provides good patency of the coronary arteries and subsequent improvement of postoperative mortality rates following ASO.


Assuntos
Transposição das Grandes Artérias , Transposição dos Grandes Vasos , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Humanos , Estudos Retrospectivos , Volume Sistólico , Transposição dos Grandes Vasos/cirurgia , Resultado do Tratamento , Função Ventricular Esquerda
7.
Pediatr Cardiol ; 42(8): 1854-1861, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34255111

RESUMO

Although De Vega annuloplasty is an important option for pediatric patients with functional tricuspid regurgitation (TR), little is known about its long-term results, including the future of the plicated annulus. We retrospectively reviewed our experience with pediatric patients who underwent the De Vega annuloplasty between 2005 and 2020. Tricuspid valve assessments were performed by transthoracic echocardiography. The targeted diameter of annular plication was 80 to 90% of normal tricuspid diameter, according to the patient's condition. The study included 55 patients (41 with biventricular physiology (group B), 14 with univentricular physiology (group U)) with a median follow-up of 5.0 years. Median age at operation was 5.0 years. There was one late death due to severe mitral regurgitation. Tricuspid valve reoperation was required in five patients and the 10-year freedom from reoperation was 91.9% for the entire cohort. The 10-year freedom from the composite adverse outcome of death, reoperation, and significant TR was 79.2% in group B versus 56.6% in group U (p = 0.034). TR grade significantly decreased after surgery (p < 0.001), without significant aggravation during the postoperative follow-up. No patients presented tricuspid stenosis. Mean Z-scores of annular diameter immediately after operation and at the latest follow-up were - 0.65 ± 0.56 versus - 0.47 ± 0.65 (p = 0.57). De Vega annuloplasty is a safe, efficient, and durable procedure for functional TR in pediatric patients including those with univentricular physiology, allowing adequate growth of the plicated annulus without the progression of tricuspid stenosis.


Assuntos
Anuloplastia da Valva Cardíaca , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Tricúspide , Valva Aórtica , Criança , Humanos , Valva Mitral/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/cirurgia
8.
Interact Cardiovasc Thorac Surg ; 33(3): 496-497, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34059906

RESUMO

Two infants with congenital heart disease developed life-threatening airway obstruction due to progressive dilatation of the aorta. Both underwent posterior aortic plication with extracorporeal bypass (9 and 4 months of age). After surgery, the arterial diameter was adequately reduced with a smooth aortic route leading to a wide airway space. Both patients were weaned from the ventilator shortly after surgery and are currently asymptomatic.


Assuntos
Obstrução das Vias Respiratórias , Doenças da Aorta , Cardiopatias Congênitas , Aorta/diagnóstico por imagem , Aorta/cirurgia , Dilatação , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/cirurgia , Humanos , Lactente
9.
J Pediatr Intensive Care ; 10(2): 85-105, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33884209

RESUMO

Pediatric patients show various extracardiac complications after cardiovascular surgery, and radiography and ultrasound are routinely performed in the intensive care unit to detect and evaluate these complications. This review presents images of these complications, sonographic approach, and timing of occurrence that are categorized based on their extracardiac locations and include complications pertaining to the central nervous system, mediastinum, thorax and lung parenchyma, diaphragm, liver and biliary system, and kidney along with pleural effusion and iatrogenic complications. This pictorial review will make it easier for medical doctors in intensive care units to identify and manage various extracardiac complications in pediatric patients after cardiovascular surgery.

10.
Radiol Case Rep ; 16(4): 777-784, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33537108

RESUMO

We demonstrate a quick sliding of the descending aorta toward the unaffected side of the diaphragm as a new sonographic finding during breathing in pediatric patients with diaphragmatic paralysis. We present three pediatric patients with diaphragmatic paralysis after cardiovascular surgery with this new sonographic finding. This finding consisted of paradoxical movement of the diaphragm as shown by fluorography. This sonographic sign was only obtained by a B-mode scan in the subxiphoid plane, was easily demonstrated at the patient's bedside, and may be useful for diagnosing severe diaphragmatic paralysis.

11.
Gen Thorac Cardiovasc Surg ; 69(4): 731-735, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33136256

RESUMO

We treated a surgical case of a 47-day-old male infant diagnosed with an unusual type of cor triatriatum sinister (CTS) with left anomalous pulmonary venous drainage to the innominate vein via a vertical vein. After preoperative hemodynamic assessment of pulmonary venous (PV) return, this patient underwent a resection of the fibromuscular membrane between the accessory and the true left atrial chambers, concomitant with vertical vein banding to facilitate a left PV return through a common pulmonary venous collector (CPVC). Catheterization three months after this surgery revealed no obstruction of the PV return to the mitral orifice as well as good growth of the CPVC as a left PV return pathway. The patient has been doing well on aspirin.


Assuntos
Coração Triatriado , Cardiopatias Congênitas , Síndrome de Cimitarra , Veias Braquiocefálicas/diagnóstico por imagem , Veias Braquiocefálicas/cirurgia , Coração Triatriado/diagnóstico por imagem , Coração Triatriado/cirurgia , Drenagem , Humanos , Lactente , Masculino , Síndrome de Cimitarra/diagnóstico por imagem , Síndrome de Cimitarra/cirurgia
12.
Pediatr Int ; 63(8): 895-902, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33205590

RESUMO

BACKGROUND: Postoperative diaphragmatic paralysis is an unavoidable complication of cardiovascular surgery. Although diaphragmatic plication, as a surgical treatment, can be performed, spontaneous recovery is possible. We aimed to identify differences in fluorographic findings of diaphragmatic paralysis between pediatric patients with and without spontaneous recovery within 1 year of intrathoracic surgery. METHODS: Ten children, who had been followed-up for at least 1 year post-surgery and who had not received diaphragmatic plication were included and classified into those with or without spontaneous recovery. The presence or absence of the paradoxical movement of the diaphragm and mediastinum was evaluated based on fluorographic findings. Fisher's exact test was used to compare the presence or absence of paradoxical movement between the groups. RESULTS: Eight patients experienced spontaneous recovery. The mean ± standard deviation time to spontaneous recovery was 150 ± 114 days (range, 18-338 days). In the spontaneous recovery group, no patient had paradoxical movement of the mediastinum, and a significant between-group difference was observed in the presence of the paradoxical movement of the mediastinum (present/absent in patients with vs. without spontaneous recovery: 0/8 vs. 2/0, P = 0.02). There was no significant between-group difference in paradoxical movement of the diaphragm (present/absent in patients with vs. without spontaneous recovery: 1/7 vs. 2/0, P = 0.07). Pediatric patients without paradoxical movement of the mediastinum spontaneously recovered within 1 year of intrathoracic surgery. CONCLUSIONS: Pediatric patients without paradoxical movement of the mediastinum, based on fluorography findings, spontaneously recovered within 1 year of surgery. The timing of spontaneous recovery varied between cases.


Assuntos
Paralisia Respiratória , Criança , Diafragma/diagnóstico por imagem , Humanos , Paralisia Respiratória/diagnóstico por imagem , Paralisia Respiratória/etiologia , Estudos Retrospectivos
13.
Genes Dev ; 35(1-2): 117-132, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33334825

RESUMO

The p53 tumor suppressor protein is a potent activator of proliferative arrest and cell death. In normal cells, this pathway is restrained by p53 protein degradation mediated by the E3-ubiquitin ligase activity of MDM2. Oncogenic stress releases p53 from MDM2 control, so activating the p53 response. However, many tumors that retain wild-type p53 inappropriately maintain the MDM2-p53 regulatory loop in order to continuously suppress p53 activity. We have shown previously that single point mutations in the human MDM2 RING finger domain prevent the interaction of MDM2 with the E2/ubiquitin complex, resulting in the loss of MDM2's E3 activity without preventing p53 binding. Here, we show that an analogous mouse MDM2 mutant (MDM2 I438K) restrains p53 sufficiently for normal growth but exhibits an enhanced stress response in vitro. In vivo, constitutive expression of MDM2 I438K leads to embryonic lethality that is rescued by p53 deletion, suggesting MDM2 I438K is not able to adequately control p53 function through development. However, the switch to I438K expression is tolerated in adult mice, sparing normal cells but allowing for an enhanced p53 response to DNA damage. Viewed as a proof of principle model for therapeutic development, our findings support an approach that would inhibit MDM2 E3 activity without preventing MDM2/p53 binding as a promising avenue for development of compounds to activate p53 in tumors with reduced on-target toxicities.


Assuntos
Desenvolvimento Embrionário/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Animais , Antineoplásicos Hormonais/farmacologia , Proliferação de Células/genética , Células Cultivadas , Embrião de Mamíferos/enzimologia , Ativação Enzimática/efeitos dos fármacos , Feminino , Masculino , Camundongos , Mutação , Tamoxifeno/farmacologia
14.
Kyobu Geka ; 73(12): 978-981, 2020 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-33268745

RESUMO

A 32-year-old woman was referred to our hospital for the surgical indication of sinus venosus-type atrial septal defect. Preoperative computed tomography scan revealed that the right upper pulmonary vein returned to the high superior vena cava. We performed a modified Warden procedure using a pedicle flap of the right atrial appendage along with a fresh autologous pericardium. Her postoperative course was uneventful with no venous obstruction or sinus node dysfunction. This technique is a useful surgical option for a partial anomalous pulmonary venous connection especially in adults.


Assuntos
Comunicação Interatrial , Veias Pulmonares , Síndrome de Cimitarra , Adulto , Feminino , Comunicação Interatrial/diagnóstico por imagem , Comunicação Interatrial/cirurgia , Humanos , Pericárdio , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/cirurgia , Síndrome de Cimitarra/diagnóstico por imagem , Síndrome de Cimitarra/cirurgia , Veia Cava Superior/diagnóstico por imagem , Veia Cava Superior/cirurgia
15.
J Med Ultrason (2001) ; 47(4): 625-633, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32535724

RESUMO

PURPOSE: To compare the sonographic findings between pediatric patients with/without mediastinitis after cardiovascular surgery. METHODS: We included 18 pediatric patients with suspected mediastinitis after cardiovascular surgery who underwent ultrasound. They were divided into two groups according to the presence of mediastinitis, confirmed by positive bacterial culture from the mediastinum (number with/without mediastinitis = 5/13). The following sonographic findings were compared between the groups: (1) increased parasternal fat echogenicity and (2) retrosternal mediastinal fluid collection. Additionally, sex, age, and the interval between surgery and ultrasound examination were also compared. Fisher's exact and Mann-Whitney U tests were used for statistical comparisons. RESULTS: A significant difference was observed between patients with and without mediastinitis in the presence of increased fat echogenicity around the sternum (present/absent with mediastinitis vs. present/absent without mediastinitis: 5/0 vs. 3/10, respectively; P = 0.007) and retrosternal mediastinal fluid collection (5/0 vs. 2/11, respectively; P = 0.002). There was no significant difference in sex (male/female; 3/2 vs. 6/7; P > 0.999); age (months; 12.6 ± 9.4 (range, 1-22) vs. 6.9 ± 5.4 (range, 1-21); P = 0.336); and interval between surgery and ultrasound examination (days; 12.8 ± 7.2 (range, 6-20) vs. 19.1 ± 14.9 (range, 1-45); P = 0.443). CONCLUSION: Although our cohort was small, none of the patients without increased parasternal fat echogenicity or mediastinal fluid collection was diagnosed with mediastinitis. These sonographic findings may help identify the possible presence of mediastinitis. Ultrasound may be the modality of first choice to evaluate pediatric patients for mediastinitis after cardiovascular surgery.


Assuntos
Procedimentos Cirúrgicos Cardiovasculares , Mediastinite/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Ultrassonografia/métodos , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Esterno/cirurgia
16.
Nat Commun ; 11(1): 2094, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350255

RESUMO

Phosphorylation of MDM2 by ATM upon DNA damage is an important mechanism for deregulating MDM2, thereby leading to p53 activation. ATM phosphorylates multiple residues near the RING domain of MDM2, but the underlying molecular basis for deregulation remains elusive. Here we show that Ser429 phosphorylation selectively enhances the ubiquitin ligase activity of MDM2 homodimer but not MDM2-MDMX heterodimer. A crystal structure of phospho-Ser429 (pS429)-MDM2 bound to E2-ubiquitin reveals a unique 310-helical feature present in MDM2 homodimer that allows pS429 to stabilize the closed E2-ubiquitin conformation and thereby enhancing ubiquitin transfer. In cells Ser429 phosphorylation increases MDM2 autoubiquitination and degradation upon DNA damage, whereas S429A substitution protects MDM2 from auto-degradation. Our results demonstrate that Ser429 phosphorylation serves as a switch to boost the activity of MDM2 homodimer and promote its self-destruction to enable rapid p53 stabilization and resolve a long-standing controversy surrounding MDM2 auto-degradation in response to DNA damage.


Assuntos
Dano ao DNA , Proteínas Proto-Oncogênicas c-mdm2/química , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Domínios RING Finger , Sequência de Aminoácidos , Linhagem Celular Tumoral , Humanos , Modelos Moleculares , Fosforilação , Fosfosserina/metabolismo , Ligação Proteica , Multimerização Proteica , Relação Estrutura-Atividade , Ubiquitina/metabolismo
17.
Med Ultrason ; 22(1): 108-113, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32096798

RESUMO

In contrast to computed tomography, ultrasound can be performed without radiation exposure, repeatedly performed by the patients' bedside. Hence, in this case series, we describe the evaluation of complications including hematoma, superficialsurgical site infection, mediastinitis, and pseudoaneurysm associated mediastinitis using ultrasound in pediatric patients after cardiovascular surgery. To our knowledge, no previous reports have evaluated such complications using ultrasound. Ultrasound may be useful for the early diagnosis of these complications, and in the selection of subsequent examinations such as computed tomography, resulting in the early initiation of intervention.


Assuntos
Procedimentos Cirúrgicos Cardiovasculares , Complicações Pós-Operatórias/diagnóstico por imagem , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Ultrassonografia
19.
Pediatr Int ; 62(2): 206-213, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31845441

RESUMO

BACKGROUND: To our knowledge, no systematic study has been conducted on computed tomography (CT) imaging of mediastinitis in children post-cardiovascular surgery. We aimed to assess the CT findings of pediatric patients diagnosed with mediastinitis after cardiovascular surgery. METHODS: We included 28 pediatric patients with suspected mediastinitis after undergoing cardiovascular surgery and who underwent CT. Patients were divided into a group with mediastinitis requiring antibiotic therapy (n = 15) confirmed by positive bacterial culture from the mediastinum and a group without mediastinitis (n = 13). Fisher's exact test was used to compare the following CT findings between the two groups: (i) mediastinal fluid collection; (ii) free gas bubble within fluid collection; (iii) sternal destruction; and (iv) capsular ring enhancement. The enhancement extent was categorized into the following four grades: whole rim enhancement, >50% of the rim enhancement, <50% of the rim enhancement, and no rim enhancement. A receiver operating characteristic curve analysis was performed to establish a cut-off point for obtaining the maximum diagnostic accuracy. RESULTS: A significant difference was observed between patients, with and without mediastinitis in sternal destruction (73.6% vs 0%, P = <0.0001) and capsular ring enhancement (100.0% vs 38.5%, P = 0.0004). By using a cut-off grade of the whole rim enhancement, the estimated sensitivity and specificity for mediastinitis diagnosis were 100% and 92.3%, respectively. CONCLUSION: Computed tomography findings of sternal destruction and capsular ring enhancement were observed more in patients with mediastinitis than in those without mediastinitis, and should be assessed carefully to diagnose mediastinitis accurately in pediatric patients who have undergone cardiac surgery.


Assuntos
Mediastinite/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adolescente , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Recém-Nascido , Masculino
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