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71.
Background contextThe vascular supply of the thoracic spinal cord depends on the thoracolumbar segmental arteries. Because of the small size and ventral course of these arteries in relation to the dorsal root ganglion and ventral root, they cannot be reliably identified during surgery by anatomic or morphologic criteria. Sacrificing them will most likely result in paraplegia.PurposeThe goal of this study was to evaluate a novel method of intraoperative testing of a nerve root's contribution to the blood supply of the thoracic spinal cord.Study design/settingThis is a clinical retrospective study of 49 patients diagnosed with thoracic spine tumors. Temporary nerve root clipping combined with motor-evoked potential (MEP) and somatosensory-evoked potential (SSEP) monitoring was performed; additionally, postoperative clinical evaluation was done and reported in all cases.MethodsAll cases were monitored by SSEP and MEPs. The nerve root to be sacrificed was temporarily clipped using standard aneurysm clips, and SSEP/MEP were assessed before and after clipping. Four nerve roots were sacrificed in four cases, three nerve roots in eight cases, and two nerve roots in 22 cases. Nerve roots were sacrificed bilaterally in 12 cases.ResultsMost patients (47/49) had no changes in MEP/SSEP and had no neurological deficit postoperatively. One case of a spinal sarcoma demonstrated changes in MEP after temporary clipping of the left T11 nerve root. The nerve was not sacrificed, and the patient was neurologically intact after surgery. In another case of a sarcoma, MEPs changed in the lower limbs after ligation of left T9 nerve root. It was felt that it was a global event because of anesthesia. Postoperatively, the patient had complete paraplegia but recovered almost completely after 6 months.ConclusionsTemporary nerve root clipping combined with MEP and SSEP monitoring may enhance the impact of neuromonitoring in the intraoperative management of patients with thoracic spine tumors and favorably influence neurological outcome.  相似文献   
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A 74-year-old male presented with bilateral invalidating claudication. A bilateral percutaneous transluminal angioplasty (PTA) with stenting of both superficial femoral arteries was performed but complicated by an urosepsis with Escherichia coli and a septic phlebitis at the site of an intravenous line. The phlebitis was complicated by a local abcedation for which incision and drainage were performed. One month after discharge he was readmitted at our hospital with septic fever and positive hemocultures for Escherichia coli. Positron emission tomography-computed tomographic scan (PET/CT-scan) showed a mycotic aneurysm of the thoracic aorta. Because no cryopreserved donor aorta was available and the aneurysm size rapidly increased, an open in situ repair was performed with a Dacron silver prosthesis soaked in rifampicin. His recovery was further complicated by a perforated toxic megacolon for which a subtotal colectomy was performed. Further recovery was uncomplicated and 10 months after the aortic repair patient is still free from infection.  相似文献   
74.
Choledochojejunostomy (CJS) is commonly used for biliary reconstruction in liver transplantation for primary sclerosing cholangitis (PSC). We alternatively performed choledochoduodenostomy (CDS) and side-to-side choledochodocholedochstomy in a large cohort of patients. Fifty-one patients with PSC, transplanted between 1988 and 2000, were analyzed retrospectively. Biliary reconstruction was CDS in 25 (49%), CJS in 20 (39%) and CC in 6 transplantations (12%). Biliary leaks occurred in the early follow-up (< or =41 days) only in CDS patients (20%). However, in the late follow-up (>4 months), stricturing of anastomosis was found once in CDS (4%) and CJS (5%). Later (>9 months), intrahepatic bile duct strictures were diagnosed in four CDS (16%), one CJS (5%) and one CC (17%) patient(s). In 48% of CDS (12/25), 60% of CJS (12/20) and 17% of CC (1/6) at least one incidence of cholangitis was observed. Overall, biliary complication rates were significantly higher in CDS (40%) than CJS (10%) and CC (17%); of those none in CC and 12% in CDS were anastomosis-related. Graft/patient survival showed no significant differences among groups. Based on our results we consider CJS the standard method for biliary reconstruction in PSC; however, in selected cases where CJS is difficult to accomplish because of previous surgery or for retransplantation, CDS may present an alternative technique.  相似文献   
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76.

The SARS-CoV-2 spike protein has been shown to disrupt blood–brain barrier (BBB) function, but its pathogenic mechanism of action is unknown. Whether angiotensin converting enzyme 2 (ACE2), the viral binding site for SARS-CoV-2, contributes to the spike protein-induced barrier disruption also remains unclear. Here, a 3D-BBB microfluidic model was used to interrogate mechanisms by which the spike protein may facilitate barrier dysfunction. The spike protein upregulated the expression of ACE2 in response to laminar shear stress. Moreover, interrogating the role of ACE2 showed that knock-down affected endothelial barrier properties. These results identify a possible role of ACE2 in barrier homeostasis. Analysis of RhoA, a key molecule in regulating endothelial cytoskeleton and tight junction complex dynamics, reveals that the spike protein triggers RhoA activation. Inhibition of RhoA with C3 transferase rescues its effect on tight junction disassembly. Overall, these results indicate a possible means by which the engagement of SARS-CoV-2 with ACE2 facilitates disruption of the BBB via RhoA activation. Understanding how SARS-CoV-2 dysregulates the BBB may lead to strategies to prevent the neurological deficits seen in COVID-19 patients.

Graphic Abstract
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77.
The images focus on a very rare atrial septal anatomy known as "double atrial septum with persistent interatrial space.” Only scarce reports of this anomaly are found in literature. Due to increasing use of catheter-based interventions requiring a transseptal puncture, the recognition of this anomaly is essential for performing safe and effective procedures.  相似文献   
78.

Background

Major guidelines do not recommend routine molecular profiling of lung squamous-cell carcinoma (LUSC) because the prevalence of actionable alterations is thought to be low. Increased utilization of next-generation sequencing (NGS), particularly with cell-free circulating tumor DNA, facilitates reevaluation of this premise.

Patients and Methods

We retrospectively evaluated the prevalence of actionable alterations in 2 distinct LUSC cohorts totaling 492 patients. A total of 410 consecutive patients with stage 3B or 4 LUSC were tested with a targeted cell-free circulating DNA NGS assay, and 82 patients with LUSC of any stage were tested with a tissue NGS cancer panel.

Results

In the overall cohort, 467 patients (94.9%) had a diagnosis of LUSC, and 25 patients (5.1%) had mixed histology with a squamous component. A total of 10.5% of the LUSC subgroup had somatic alterations with therapeutic relevance, including in EGFR (2.8%), ALK/ROS1 (1.3%), BRAF (1.5%), and MET amplification or exon 14 skipping (5.1%). Sixteen percent of patients with mixed histology had an actionable alteration. In the LUSC subgroup, 3 evaluable patients were treated with targeted therapy for an actionable alteration; all of them experienced partial response.

Conclusion

In this large, real-world LUSC cohort, we observed a clinically significant prevalence of actionable alterations. Accurate local histopathologic assessment in advanced-stage LUSC can be challenging. Further evaluation of the genomic landscape in this setting is warranted to potentially identify underappreciated treatment options.  相似文献   
79.
There has been a sharp rise of reported handheld laser-induced maculopathy (HLIM) cases over the past decade, a concerning trend that may continue due to unregulated online access to high power lasers. Though HLIM has distinct clinical features, not uncommonly it may masquerade as other retinal disorders. It is critical therefore to recognise the clinical and multimodal imaging characteristics of this important and potentially devastating condition. As HLIM patients are typically young, unique issues need to be considered, such as delayed presentation, difficult history, poor compliance and behavioural or psychiatric comorbidity. This article will review the clinical and diagnostic features of laser injury, with a special emphasis on the multimodal retinal findings. In addition, we present a unique case of HLIM, resembling the presentation of a placoid disease variant and illustrating choroidal ischaemia using advanced retinal imaging, that offers further insight into the mechanisms of laser injury and its complications. The issues addressed in this review aim to increase recognition of an increasingly important and trending condition with potentially profound visual complications.Subject terms: Retinal diseases, Paediatrics, Trauma  相似文献   
80.
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