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1.

Objective

Arch obstruction after the Norwood procedure is common and contributes to mortality. We determined the prevalence, associated factors, and practice variability of arch reintervention and assessed whether arch reintervention is associated with mortality.

Methods

From 2005 to 2017, 593 neonates in the Congenital Heart Surgeons' Society Critical Left Heart Obstruction cohort underwent a Norwood procedure. Median follow-up was 3.7 years. Multivariable parametric models, including a modulated renewal analysis, were performed.

Results

Of the 593 neonates, 146 (25%) underwent 218 reinterventions for arch obstruction after the Norwood procedure: catheter-based (n = 168) or surgical (n = 50) at a median age of 4.3 months (quartile 1-quartile 3, 2.6-5.7). Interdigitation of the distal aortic anastomosis was protective against arch reintervention. Development of ≥ moderate tricuspid valve regurgitation and right ventricular dysfunction at any point was associated with arch reintervention. Nonsignificant variables for arch reintervention included shunt type and preoperative aortic measurements. Surgical arch reintervention was protective against arch reintervention, but transcatheter reintervention was associated with increased reintervention. Arch reintervention was not associated with increased mortality. There was wide institutional variation in incidence of arch reintervention (range, 0-40 reinterventions per 100 years patient follow-up) and in preintervention gradient (range, 0-64 mm Hg).

Conclusions

Interdigitation of the distal aortic anastomosis during the Norwood procedure decreased the risk of arch reintervention. Surgical arch reintervention is more definitive than transcatheter. Arch reintervention after the Norwood procedure is not associated with increased mortality. Serial surveillance for arch obstruction, integrated with changes in right ventricular function and tricuspid valve regurgitation, is recommended after the Norwood procedure to improve outcomes.  相似文献   
2.
Antibody-mediated rejection (AMR) after liver transplantation is recognized in ABO incompatible and xeno-transplantation, but its role after ABO compatible liver transplantation is controversial. We report a case of ABO compatible liver transplantation that demonstrated clinical, serological and histological signs of AMR without evidence of concurrent acute cellular rejection. AMR with persistently high titers of circulating donor specific antibodies resulted in graft injury with initial centrilobular hepatocyte necrosis, fibroedematous portal expansion mimicking biliary tract outflow obstruction, ultimately resulting in extensive bridging fibrosis. Immunofluorescence microscopy demonstrated persistent, diffuse linear C4d deposits along sinusoids and central veins. Despite intense therapeutic intervention including plasmapheresis, IVIG and rituximab, AMR led to graft failure. We present evidence that an antibody-mediated alloresponse to an ABO compatible liver graft can cause significant graft injury independent of acute cellular rejection. AMR shows distinct histologic changes including a characteristic staining profile for C4d.  相似文献   
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Microinjection of the indirect GABAA antagonist, picrotoxin, or the mu opioid agonist, Tyr-D-Ala-Gly-NMe-Phe-Gly-ol (DAGO), into the ventral pallidum and substantia innominata (VP/SI) increases locomotor activity in rats. The VP/SI has direct and indirect projections to the region of the ventral mesencephalon containing dopamine perikarya, and to certain dopamine terminal fields, including the nucleus accumbens. Thus, it is possible that modulation of the mesocorticolimbic dopamine system by pharmacological stimulation in the VP/SI may play a role in the locomotor stimulant response. It was shown that pretreatment with dopamine receptor antagonists, either peripherally or microinjected into the nucleus accumbens significantly attenuated the motor stimulant effect of DAGO or picrotoxin injection into the VP/SI. Injection of either picrotoxin or DAGO into the VP/SI increased the levels of dopamine metabolites in the nucleus accumbens and prefrontal cortex. Thus, the motor stimulant response following pharmacological stimulation of the VP/SI appears to be mediated by increased dopamine neurotransmission via feedback mechanisms to the mesocorticolimbic dopamine system.  相似文献   
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The role of an operation in patients receiving neoadjuvant chemotherapy for clinically localized but invasive transitional cell carcinoma of the bladder currently is evolving. An operation is essential for case selection and evaluation of local response but it also contributes to bladder preservation and survival. The procedure that is necessary to select for and assess response to chemotherapy may itself alter the actual or proceed to evolution of invasive bladder cancer. Neoadjuvant chemotherapy is a reasonable therapeutic strategy in selected patients but it remains to be seen whether the results will prove to be superior to those achieved with standard endoscopic and open operations.  相似文献   
9.
Updated information on the pathologic characterization and treatment of olfactory neurobiastoma (ON) and neuroendocrine carcinoma (NEC) diseases is presented. A series of patients with ON or NEC was evaluated and retrospectively staged using the UCLA system. The parameters evaluated were symptoms, age, sex, risk factor assessment, stage of disease, treatment, and clinical outcome. The median follow-up was 3 years (range, 18 months to 23 years). The predominant therapy (63%) for ON was combined surgery and radiotherapy. Surgery alone or in combination with ancillary treatment was used in 58% of patients with NEC. For the most receat years of the study, patients with NEC have been treated successfully with combined chemotherapy and radiotherapy. Seventy percent of the patients with ON and 75% of the patients with NEC were clinically free of disease during the defined follow-up period. Surgical therapy consisting of a craniofacial resection combined with postoperative radiotherapy has resulted in good local and long-term control of ON. Our experience indicates that combined chemoradiation is an appropriate therapeutic approach for NEC.  相似文献   
10.
Surgical treatment of brain metastases from renal cell carcinoma   总被引:1,自引:0,他引:1  
Between January 1976 and December 1986, 22 patients with renal cell carcinoma underwent surgical resection of brain metastases at Memorial Sloan-Kettering Cancer Center. Ten of the patients had metastases limited to the brain and 12 also had extracranial metastases. Twenty patients received external radiotherapy. Five had craniotomy after failing radiation therapy and 15 had adjuvant radiotherapy. Two patients died within thirty days following craniotomy; the median survival of the remaining 20 patients was 20.9 +/- 6.8 months calculated according to a Weibull survival model. Variables examined in relation to survival included absence or presence of extracranial metastases at time of craniotomy, time interval between nephrectomy and diagnosis of cerebral metastases, neurologic status prior to craniotomy, location of the brain tumor, and patient age. None of the variables was significant at the 10 percent level by the Weibull analysis. However, three favorable prognostic factors, namely metachronous brain metastasis more than one year after nephrectomy, minimal or no neurologic deficit at time of craniotomy, and infratentorial lesions show a trend toward improved survival with p less than 0.20. The data suggest that surgical resection of a single and occasionally multiple brain metastases is warranted in selected patients with renal cell carcinoma.  相似文献   
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