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Background

Although the majority of patients with minimal acute subdural hematomas (aSDHs) can be managed conservatively, some require delayed aSDH evacuation due to hematoma enlargement. This study was designed to determine the risk factors associated with delayed hematoma enlargement leading to surgery in patients with aSDHs who did not initially require surgical intervention.

Methods

From 2002 to 2012, 98 patients were treated for nonoperative aSDHs following mild head injury (Glasgow Coma Scale scores of 13–15). The outcome variables were radiographic evidence of SDH enlargement on serially obtained computed tomography (CT) images and later surgical evacuation. Univariate and multivariate analyses were applied to both the demographic and initial radiographic features to identify risk factors for SDH progression and surgery.

Results

Overall, 64 patients (65 %) revealed minimal SDH or spontaneous hematoma resolution (conservative group) with conservative management at their last follow-up CT scan. The remaining 34 patients (35 %) received delayed hematoma evacuation (delayed surgery group) a median of 17 days after the head trauma. There were no significant differences between the two groups for baseline characteristics, including age, injury type, degree of brain atrophy, prior history of antithrombotic drugs, and coagulopathy. The presence of cerebral contusions and subarachnoid hemorrhages was more common in the conservative group (p?=?0.003 and p?=?0.003, respectively). On multivariate analysis, hematoma volume (p?=?0.01, odds ratio [OR]?=?1.094, 95 % confidence interval [CI]?=?1.021–1.173) and degree of midline shift (p?=?0.01, OR?=?1.433, 95 % CI?=?1.088–1.888) on the initial CT scan were independently associated with delayed hematoma evacuation.

Conclusions

A critical proportion of patients with minimal aSDHs occurring after mild head injury can progress over several weeks and require hematoma evacuation. Especially patients with a large initial SDH volume and accompanying midline shift require careful monitoring of hematoma progression.  相似文献   
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Aim

The aim of the present study was to determine (1) whether successful intraoperative electromyography monitoring for lateral spread response (LSR) is possible with partial neuromuscular blockade (NMB) in subjects undergoing microvascular decompression (MVD) for hemifacial spasm and (2) the adequate level of NMB to achieve that goal.

Material and methods

A total of 61 patients in whom LSR was monitored during MVD were enrolled in the study. Patients were randomly allocated to two groups: group TOF in which the NMB target was maintenance of two train-of-four (TOF) counts and group T1 in which the NMB target was maintenance of a T1/Tc ratio of 50?% (T1: first twitch height of TOF and Tc: control twitch height). The adductor pollicis brevis muscle was used to monitor TOF responses. The frequency of successful LSR monitoring, defined as successful baseline establishment and maintenance of LSR until surgical decompression, was compared between the two groups.

Results

Of the 61 patients 2 were excluded from the study so that 30 patients in group TOF and 29 patients in group T1 were analyzed. The success rate of LSR monitoring was clinically acceptable and significantly higher in group T1 than in group TOF, i.e. n?=?15 (50.0?%) in group TOF versus n?=?24 (82.8?%) in group T1 (P?=?0.008), corresponding to a 32.8?% higher success rate in group T1 than group TOF (95?% CI: 13.9–51.7?%). Mean vecuronium infusion dose was smaller and mean TOF count was higher in group T1 than group TOF with a TOF count =?2 (1) in group TOF versus 3 (1) in group T1 (P?=?0.003). Mean sevoflurane and remifentanil infusion doses were not different between groups. There was no incidence of spontaneous movement during microscopy in either group.

Conclusion

Maintenance of partial NMB with a target T1/Tc ratio of 50?% resulted in a clinically acceptable success rate of LSR monitoring and surgical condition during MVD. Maintenance of partial NMB with a target T1/Tc ratio of 50?% rather than TOF count of two during LSR monitoring for MVD can therefore be recommended.  相似文献   
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Impaired angiogenesis in ischemic tissue is a hallmark of diabetes. Thioredoxin-interacting protein (TXNIP) is an exquisitely glucose-sensitive gene that is overexpressed in diabetes. As TXNIP modulates the activity of the key angiogenic cytokine vascular endothelial growth factor (VEGF), we hypothesized that hyperglycemia-induced dysregulation of TXNIP may play a role in the pathogenesis of impaired angiogenesis in diabetes. In the current study, we report that high glucose–mediated overexpression of TXNIP induces a widespread impairment in endothelial cell (EC) function and survival by reducing VEGF production and sensitivity to VEGF action, findings that are rescued by silencing TXNIP with small interfering RNA. High glucose–induced EC dysfunction was recapitulated in normal glucose conditions by overexpressing either TXNIP or a TXNIP C247S mutant unable to bind thioredoxin, suggesting that TXNIP effects are largely independent of thioredoxin activity. In streptozotocin-induced diabetic mice, TXNIP knockdown to nondiabetic levels rescued diabetes-related impairment of angiogenesis, arteriogenesis, blood flow, and functional recovery in an ischemic hindlimb. These findings were associated with in vivo restoration of VEGF production to nondiabetic levels. These data implicate a critical role for TXNIP in diabetes-related impairment of ischemia-mediated angiogenesis and identify TXNIP as a potential therapeutic target for the vascular complications of diabetes.  相似文献   
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Purpose

The purpose of this study was to characterize the growth rate of sacrococcygeal teratomas (SCTs) and determine its relationship to adverse outcomes.

Methods

A retrospective review of all pathology-confirmed isolated SCT patients evaluated with at least two documented ultrasounds and followed through hospital discharge between 2005 and 2012 was conducted. SCT growth rate was calculated as the difference between tumor volumes on a late- and early-gestation ultrasound divided by the difference in time. Outcomes were death, high-output cardiac failure (HOCF), hydrops, and preterm delivery. Student's t-test, receiver operator characteristics, Fisher's Exact test, and Pearson's correlation were performed.

Results

Of the 28 study subjects, there were 3 in utero demises and 2 neonatal deaths. Significantly faster SCT growth rates were seen in all adverse outcomes, including death (p < 0.0001), HOCF (p = 0.005), and preterm delivery (p = 0.009). There was a significant association with adverse outcomes at > 61 cm3/week (AUC = 0.87, p = 0.001, LR = 4.52). Furthermore, there was an even greater association with death at > 165 cm3/week (AUC = 0.93, p = 0.003, LR = 18.42). Growth rate was directly correlated with the percent of solid tumor (r = 0.60, p = 0.0008).

Conclusion

Faster SCT growth is associated with adverse outcomes. SCT growth rate determined by ultrasound is an effective prognostic indicator for adverse outcomes and easily applied to patient management.  相似文献   
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Intermittent parathyroid hormone (PTH) administration has a potent ability to increase bone mass, regardless of underlying conditions or species. A recent study using LDLR ?/? mice showed that the anabolic effect of PTH was blunted by hyperlipidemia, whereas PTH anabolism was rescued by enhancement of high-density lipoprotein cholesterol (HDL-C) function. We conducted a retrospective longitudinal study to determine whether lipid profiles also affect the anabolic effect of intermittent PTH treatment in humans. Fifty-two patients (8 males and 44 females, ages 38–85 years) with severe osteoporosis who had been treated with teriparatide (TPTD, recombinant human PTH(1–34) for 12 months were studied at Severance Hospital, Yonsei University. C-telopeptide (CTX) and osteocalcin (OCN) were measured at 0, 3, and 12 months; and total cholesterol, triglycerides, and HDL-C were measured at baseline. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry at 0 and 12 months. Lumbar spine BMD increased significantly after 12 months of treatment with TPTD (10.0 ± 9.3 %, p < 0.001). Initial 3-month changes in CTX and OCN levels revealed positive correlations with the increase in lumbar BMD (r = 0.546, p = 0.001 and r = 0.500, p = 0.006, respectively). Moreover, percentage change in lumbar BMD at 12 months showed a negative correlation with baseline total cholesterol (r = ?0.438, p = 0.009) and a positive correlation with HDL-C (r = 0.498, p = 0.016). A smaller 3-month increase in OCN and a lower HDL-C level at baseline were associated with a smaller lumbar BMD increase after TPTD treatment, even after adjustment for age, sex, and other confounding factors (β = 0.462, p = 0.031 for ΔOCN and β = 0.670, p = 0.004 for HDL-C). Plasma levels of lipids, especially HDL-C, seem to be associated with the extent of osteoanabolic effects of TPTD in humans.  相似文献   
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