Prognosis After Brain Metastasis from Differentiated Thyroid Carcinoma

Background

In patients with differentiated thyroid carcinoma (DTC), lung and bone metastasis sometimes occur. However, brain metastasis (BM) is extremely rare. Because most previous reports about BM from DTC included a relatively small number of cases, the clinical characteristics and outcomes of BM are still unclear.

Patients and methods

Between 1965 and 2013, among 961 patients who had died because of DTC, 24 patients were diagnosed with BM from DTC. One patient with BM from DTC is still alive. To identify the prognostic factors for longer survival after BM, the medical records of these 25 patients were retrospectively reviewed.

Results

The median age at BM diagnosis was 66 years. Typical symptoms associated with BM had appeared in 20 patients (80 %). The Karnofsky Performance Status (KPS) was good (≥70) in 10 patients and poor (≤60) in 15 patients. Seven patients had a single intracranial lesion of BM, 6 patients had 2 or 3 lesions, and 9 patients had 4 or more. Eleven patients did not receive any treatment for BM, and 14 patients underwent surgical resection, radiation therapy, or both. One-year and 5-year disease-specific survival rates were 28 and 10.6 %, respectively. Good KPS (≥70), small number of intracranial lesions (≤3), and treatment for BM were prognostic factors for long survival on univariate analysis (p < 0.05). On multivariate analysis, only treatment for BM was significant.

Conclusion

Treatment of BM from DTC is indicated in patients who have a good KPS and fewer intracranial lesions, and some of them may achieve long survival.

     

Detection of thrombosis in a magnetically levitated blood pump by vibrational excitation of the impeller

The use of contactless support technology for the impeller has led to an increase in the durability of ventricular assist devices (VADs), and these have been in clinical use worldwide. However, pump thrombosis and stroke are still issues to be solved. We have developed a method for detecting the thrombosis in a magnetically levitated blood pump without the need for additional sensors or other equipment. In the proposed method, a sinusoidal current is applied to the electromagnets used for the magnetic bearing, resulting in vibration of the impeller. The phase difference between the current and displacement of the impeller increases with pump thrombosis. First, we describe the principle by which the pump thrombosis is detected. Pump thrombosis reduces the narrowest fluid gap in the pump and this gives rise to a change in the phase difference. Second, we report on experiments in which we changed the narrowest fluid gap using oriented polypropylene tape and showed that decreasing the narrowest fluid gap resulted in an increase in phase difference. For these experiments, the measurements were repeated three times for each condition. Third, we examine the relationship between the pump thrombosis and the phase difference evaluated by observations of the underside of the impeller when operating the pump with porcine blood. Since light was unable to penetrate the blood layer, the erythrocytes were removed for this observation. Only one observation was made. The results showed the phase difference rapidly increased at the same moment when the pump thrombosis was observed. This implies the proposed method has the potential to detect the early stages of pump thrombosis. Finally, in vitro experiments to detect thrombosis when using whole porcine blood in the pump were conducted. The experiment was carried out five times. To intentionally form a thrombus inside the pump, the activated clotting time was controlled to be less than 200 s. In every case, the phase difference increased by more than one degree after tens of minutes. Then, the pump was disassembled and a small amount of pump thrombosis was observed. We conclude that real-time diagnosis of pump thrombosis may be realized by measuring the phase difference without the need for additional sensors.     

Relationship between serum uric acid level and vascular injury markers in hemodialysis patients

Purpose

It has been reported that hyperuricemia causes vascular endothelial injury. Most hemodialysis patients present with hyperuricemia and also with vascular injury, resulting in cardiovascular diseases (CVD). However, the association of serum uric acid (sUA) with vascular injury markers in hemodialysis patients remains unclear. This study aimed to investigate this and discuss the mechanism by which uric acid causes vascular injury.

Methods

We enrolled 48 Japanese maintenance hemodialysis patients without any history of CVD. The association between sUA level and three vascular injury markers (reactive hyperemia index [RHI], ankle–brachial index [ABI], and cardio ankle vascular index [CAVI]) was investigated by linear- and logistic regression analyses.

Results

The median natural logarithm RHI (LnRHI) was 0.36. Linear regression analysis revealed a significant positive correlation between sUA level and LnRHI (β?=?0.42, p?=?0.001) in all patients. Moreover, a significant, strongly positive correlation was observed between sUA and LnRHI in patients who were treated with xanthine oxidase inhibitors (XOIs) (β?=?0.75, p?=?0.001). Further, the linear analysis showed a significant negative correlation between sUA level and CAVI in patients who were treated with XOIs (β?=?? 0.52, p?=?0.049). sUA level was not significantly associated with ABI abnormality.

Conclusions

It is possible that a high level of sUA is significantly associated with better vascular endothelial function and condition of vascular tone in hemodialysis patients who were treated with XOIs. The findings suggest a significant paradox between sUA level and vascular endothelial function in hemodialysis patients; however, the opposite has been reported in patients without hemodialysis.

     

Spinal cord injury following aortic arch replacement

Surgery Today - Postoperative spinal cord injury is a devastating complication after aortic arch replacement. The purpose of this study was to determine the predictors of this complication. A group...     

Effects of three kinds of erythropoiesis-stimulating agents on renal anemia in Japanese non-dialysis chronic kidney disease patients

Background

Erythropoiesis-stimulating agents (ESAs) are standard therapy for chronic kidney disease (CKD) patients with renal anemia. However, few studies have compared the effects of different ESAs on anemia in identical pre-dialysis CKD patients.

Methods

Seventy-nine patients who switched from epoetin beta to darbepoetin alfa (Group 1), and 82 patients who switched from darbepoetin alfa to epoetin beta pegol (Group 2) were enrolled in this study. Clinical and laboratory parameters were assessed for 6 months before and after switching ESAs. The prevalence of adverse events, the dose conversion ratio of ESAs, and the frequency of ESA administration were also analyzed.

Results

Analysis of variance showed that switching ESAs did not significantly change hemoglobin levels for the study duration in both groups (mean hemoglobin 10.3–10.5 g/dL in Group 1 and 10.4–10.7 g/dL in Group 2). Estimated glomerular filtration rate, blood pressure, transferrin saturation, ferritin, and albumin remained constant in both groups. The prevalence of adverse effects was quite low (0–3.8 %) during both 6-month study periods. The mean dose conversion ratio for epoetin beta:darbepoetin alfa was 163.7 units:1 μg and for darbepoetin alfa:epoetin beta pegol was 1.08 μg:1 μg. The intervals of ESA administration significantly differed (epoetin beta pegol > darbepoetin alfa > epoetin beta).

Conclusions

Epoetin beta, darbepoetin alfa, and epoetin beta pegol are effective and well-tolerated agents for managing anemia in Japanese pre-dialysis CKD patients. The intervals of ESA administration to maintain a patient’s target hemoglobin were longer in the order of epoetin beta pegol > darbepoetin alfa > epoetin beta.