Saint Cloud, MN, United States
Saint Cloud, MN, United States

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Miller V.M.,200 1st St SW | Garovic V.D.,200 1st St SW | Kantarci K.,200 1st St SW | Barnes J.N.,200 1st St SW | And 4 more authors.
Biology of Sex Differences | Year: 2013

Understanding the biology of sex differences is integral to personalized medicine. Cardiovascular disease and cognitive decline are two related conditions, with distinct sex differences in morbidity and clinical manifestations, response to treatments, and mortality. Although mortality from all-cause cardiovascular diseases has declined in women over the past five years, due in part to increased educational campaigns regarding the recognition of symptoms and application of treatment guidelines, the mortality in women still exceeds that of men. The physiological basis for these differences requires further research, with particular attention to two physiological conditions which are unique to women and associated with hormonal changes: pregnancy and menopause. Both conditions have the potential to impact life-long cardiovascular risk, including cerebrovascular function and cognition in women. This review draws on epidemiological, translational, clinical, and basic science studies to assess the impact of hypertensive pregnancy disorders on cardiovascular disease and cognitive function later in life, and examines the effects of post-menopausal hormone treatments on cardiovascular risk and cognition in midlife women. We suggest that hypertensive pregnancy disorders and menopause activate vascular components, i.e., vascular endothelium and blood elements, including platelets and leukocytes, to release cell-membrane derived microvesicles that are potential mediators of changes in cerebral blood flow, and may ultimately affect cognition in women as they age. Research into specific sex differences for these disease processes with attention to an individual's sex chromosomal complement and hormonal status is important and timely. © 2013 Miller et al.; licensee BioMed Central Ltd.


McDonald J.S.,200 1st St SW | Katzberg R.W.,Medical University of South Carolina | McDonald R.J.,200 1st St SW | Williamson E.E.,200 1st St SW | Kallmes D.F.,200 1st St SW
Radiology | Year: 2016

Purpose: To determine whether patients with a solitary kidney are at higher risk for contrast material-induced acute kidney injury (AKI) than matched control patients with bilateral kidneys. Materials and Methods: This retrospective study was HIPAA compliant and approved by the institutional review board. Adult patients with bilateral kidneys or a solitary kidney from unilateral nephrectomy who underwent contrast material-enhanced computed tomography (CT) at this institution from January 2004 to August 2013 were identified. The effects of contrast material exposure on the rate of AKI defined as an increase in maximal observed serum creatinine (SCr) level of either (a) ≥0.5 mg/dL (44.2 mmol/L) or (b) ≥0.3 mg/dL (26.52 mmol/L) or 50% over baseline within 24-72 hours of exposure and 30-day post-CT emergent dialysis and death were determined after propensity score-based 1:3 matching of patients with solitary kidneys and control patients with bilateral kidneys. Differences in clinical characteristics and outcomes between the solitary and bilateral kidney groups were assessed by using the Wilcoxon rank sum test or Pearson x2 test prior to matching and by using conditional logistic regression after matching. Results: Propensity score matching yielded a cohort of 247 patients with solitary kidneys and 691 patients with bilateral kidneys. The rate of AKI was similar between the solitary and bilateral kidney groups (SCr ≥ 0.5 mg/dL AKI definition odds ratio = 1.11 [95% confidence interval {CI}: 0.65, 1.86], P = .70; SCr ≥ 0.3 mg/dL or 50% over baseline AKI definition odds ratio = 0.96 [95% CI: 0.41, 2.07], P = .99). The rate of emergent dialysis was rare and also similar between cohorts (odds ratio = 1.87 [95% CI: 0.16, 16.4], P = .61). Although the rate of mortality was higher in the solitary kidney group (odds ratio = 1.70 [95% CI: 1.06, 2.71], P = .0202), chart review showed that no death was attributable to AKI. Conclusion: Our study did not demonstrate any significant differences in the rate of AKI, dialysis, or death attributable to contrast-enhanced CT in patients with a solitary kidney versus bilateral kidneys. © RSNA, 2016.


Gu C.N.,200 1st St SW | Brinjikji W.,200 1st St SW | El-Sayed A.M.,Columbia University | Cloft H.,200 1st St SW | And 4 more authors.
American Journal of Neuroradiology | Year: 2014

BACKGROUND AND PURPOSE: Vertebroplasty and kyphoplasty are frequently utilized in the treatment of symptomatic vertebral body fractures. While prior studies have demonstrated disparities in the treatment of back pain and care for osteoporotic patients, disparities in spine augmentation have not been investigated. We investigated racial and health insurance status differences in the use of spine augmentation for the treatment of osteoporotic vertebral fractures in the United States.MATERIALS AND METHODS: Using the Nationwide Inpatient Sample from 2005 to 2010, we selected all discharges with a primary diagnosis of vertebral fracture (International Classification of Diseases-9 code 733.13). Patients who received spine augmentation were identified by using International Classification of Diseases-9 procedure code 81.65 for vertebroplasty and 81.66 for kyphoplasty. Patients with a diagnosis of cancer were excluded. We compared usage rates of spine augmentation by race/ethnicity (white, black, Hispanic, and Asian/Pacific Islander) and insurance status (Medicare, Medicaid, self-pay, and private). Comparisons among groups were made by using x2 tests. A multivariate logistic regression analysis was fit to determine variables associated with spine augmentation use.RESULTS: A total of 228,329 patients were included in this analysis, ofwhom129,206 (56.6%) received spine augmentation. Among patients with spine augmentation, 97,022 (75%) received kyphoplasty and 32,184 (25%) received vertebroplasty; 57.5% (92,779/161,281) of white patients received spine augmentation compared with 38.7% (1405/3631) of black patients (P < .001). Hispanic patients had significantly lower spine augmentation rates compared with white patients (52.3%, 3777/7222, P < .001) as did Asian/Pacific Islander patients (53.1%, 1784/3361, P<.001). The spine augmentation usage rate was 57.2% (114,768/200,662) among patients with Medicare, significantly higher than that of those with Medicaid (43.9%, 1907/4341, P < .001) and those who self-pay (40.2%, 488/1214, P < .001).CONCLUSIONS: Our findings demonstrate substantial racial and health insurance- based disparities in the inpatient use of spinal augmentation for the treatment of osteoporotic vertebral fracture.


Limberg J.K.,200 1st St SW | Taylor J.L.,200 1st St SW | Mozer M.T.,200 1st St SW | Dube S.,Mayo Medical School | And 6 more authors.
Hypertension | Year: 2015

Hypoglycemia results in a reduction in cardiac baroreflex sensitivity and a shift in the baroreflex working range to higher heart rates. This effect is mediated, in part, by the carotid chemoreceptors. Therefore, we hypothesized hypoglycemia-mediated changes in baroreflex control of heart rate would be blunted in carotid body-resected patients when compared with healthy controls. Five patients with bilateral carotid body resection for glomus tumors and 10 healthy controls completed a 180-minute hyperinsulinemic, hypoglycemic (≈3.3 mmol/L) clamp. Changes in heart rate, blood pressure, and spontaneous cardiac baroreflex sensitivity were assessed. Baseline baroreflex sensitivity was not different between groups (P>0.05). Hypoglycemia resulted in a reduction in baroreflex sensitivity in both the groups (main effect of time, P<0.01) and responses were lower in resected patients when compared with controls (main effect of group, P<0.05). Hypoglycemia resulted in large reductions in systolic (-17±7 mm Hg) and mean (-14±5 mm Hg) blood pressure in resected patients that were not observed in controls (interaction of group and time, P<0.05). Despite lower blood pressures, increases in heart rate with hypoglycemia were blunted in resected patients (interaction of group and time, P<0.01). Major novel findings from this study demonstrate that intact carotid chemoreceptors are essential for increasing heart rate and maintaining arterial blood pressure during hypoglycemia in humans. These data support a contribution of the carotid chemoreceptors to blood pressure control and highlight the potential widespread effects of carotid body resection in humans. © 2015 American Heart Association, Inc.


Au J.K.,Baylor College of Medicine | Tan X.,Baylor College of Medicine | Sidani M.,Baylor College of Medicine | Stanasel I.,Baylor College of Medicine | And 8 more authors.
Journal of Pediatric Urology | Year: 2016

Introduction: Some children who sustain high-grade blunt renal injury may require operative intervention. In the present study, it was hypothesized that there are computed tomography (CT) characteristics that can identify which of these children are most likely to need operative intervention. Materials and methods: A retrospective review was performed of all pediatric blunt renal trauma patients at a single level-I trauma center from 1990 to 2015. Inclusion criteria were: children with American Association for the Surgery of Trauma (AAST) Grade-IV or V renal injuries, aged ≤18 years, and having available CT images with delayed cuts. The CTs were regraded according to the revised AAST grading system proposed by Buckley and McAninch in 2011. Radiographic characteristics of renal injury were correlated with the primary outcome of any operative intervention: ureteral stent, angiography, nephrectomy/renorrhaphy, and percutaneous nephrostomy/drain. Results: One patient had a Grade-V injury and 26 patients had Grade-IV injuries. Nine patients (33.3%) underwent operative interventions. Patients in the operative intervention cohort were more likely to manifest a collecting system filling defect (P = 0.040) (Fig. A) and lacked ureteral opacification (P = 0.010). The CT characteristics, including percentage of devascularized parenchyma, medial contrast extravasation, intravascular contrast extravasation, perirenal hematoma distance and laceration location, were not statistically significant. Of the 21 patients who had a collecting system injury, eight (38.1%) needed ureteral stents. Renorrhaphy was necessary for one patient. Although the first operative intervention occurred at a median of hospital day 1 (range 0.5-2.5), additional operative interventions occurred from day 4-16. Thus, it is prudent to closely follow-up these patients for the first month after injury. Two patients with complex renal injuries had an accessory renal artery resulting in well-perfused upper and lower pole fragments, and were managed nonoperatively without readmission (Fig. B). Conclusions: Collecting system defects and lack of ureteral opacification were significantly associated with failure of nonoperative management. A multicenter trial is needed to confirm these findings and whether nonsignificant CT findings are associated with operative intervention. In the month after renal injury, these patients should be mindful of any changes in symptoms, and maintain a low index of suspicion for an emergency room visit. For the physician, close follow-up and appropriate counseling of these high-risk patients is advised.Display Omitted. © 2016 Journal of Pediatric Urology Company.


Kumar R.,200 1st St. SW | Jacob J.T.,200 1st St. SW | Welker K.M.,Mayo Medical School | Cutrer F.M.,Mayo Medical School | And 3 more authors.
Journal of Neurosurgery | Year: 2015

This report reviews a series of 3 patients who developed superficial siderosis following posterior fossa operations in which dural closure was incomplete. In all 3 patients, revision surgery and complete duraplasty was performed to halt the progression of superficial siderosis. Following surgery, 2 patients experienced resolution of their CSF xanthochromia while 1 patient had reduced CSF xanthochromia. In this paper the authors also review the etiology, pathophysiology, diagnosis, and treatment of this condition. The authors suggest that posterior fossa dural patency and pseudomeningocele are risk factors for the latent development of superficial siderosis and recommend that revision duraplasty be performed in patients with posterior fossa pseudomeningoceles and superficial siderosis to prevent progression of the disease. © AANS, 2015.


PubMed | 200 1st St SW and Baylor College of Medicine
Type: Journal Article | Journal: Journal of pediatric urology | Year: 2016

Some children who sustain high-grade blunt renal injury may require operative intervention. In the present study, it was hypothesized that there are computed tomography (CT) characteristics that can identify which of these children are most likely to need operative intervention.A retrospective review was performed of all pediatric blunt renal trauma patients at a single level-I trauma center from 1990 to 2015. Inclusion criteria were: children with American Association for the Surgery of Trauma (AAST) Grade-IV or V renal injuries, aged 18 years, and having available CT images with delayed cuts. The CTs were regraded according to the revised AAST grading system proposed by Buckley and McAninch in 2011. Radiographic characteristics of renal injury were correlated with the primary outcome of any operative intervention: ureteral stent, angiography, nephrectomy/renorrhaphy, and percutaneous nephrostomy/drain.One patient had a Grade-V injury and 26 patients had Grade-IV injuries. Nine patients (33.3%) underwent operative interventions. Patients in the operative intervention cohort were more likely to manifest a collecting system filling defect (P=0.040) (Fig. A) and lacked ureteral opacification (P=0.010). The CT characteristics, including percentage of devascularized parenchyma, medial contrast extravasation, intravascular contrast extravasation, perirenal hematoma distance and laceration location, were not statistically significant. Of the 21 patients who had a collecting system injury, eight (38.1%) needed ureteral stents. Renorrhaphy was necessary for one patient. Although the first operative intervention occurred at a median of hospital day 1 (range 0.5-2.5), additional operative interventions occurred from day 4-16. Thus, it is prudent to closely follow-up these patients for the first month after injury. Two patients with complex renal injuries had an accessory renal artery resulting in well-perfused upper and lower pole fragments, and were managed nonoperatively without readmission (Fig. B).Collecting system defects and lack of ureteral opacification were significantly associated with failure of nonoperative management. A multicenter trial is needed to confirm these findings and whether nonsignificant CT findings are associated with operative intervention. In the month after renal injury, these patients should be mindful of any changes in symptoms, and maintain a low index of suspicion for an emergency room visit. For the physician, close follow-up and appropriate counseling of these high-risk patients is advised.


PubMed | 200 1st St SW
Type: Case Reports | Journal: Pediatrics | Year: 2013

For more than a decade there has been considerable interest in the role of QT interval prolongation in the pathogenesis of sudden infant death syndrome. It has been proposed that the QT interval is a surrogate marker for autonomic instability and can be used to identify infants at risk for significant morbidity and mortality, including sudden infant death syndrome. We present the case of an infant that experienced a significant increase in his QTc, as detected by continuous QTc monitoring in the NICU after repositioning from a supine to prone position. This increase from a 413 6 millisecond baseline average to 500 milliseconds was sustained for 2 hours and associated with clinically relevant apnea that ultimately required repositioning of the infant back to the supine position. Repositioning resulted in an immediate decrease of the QTc back to the previous baseline and termination of the apneic events. This case demonstrates an example of how the use of continuous QTc monitoring in the NICU setting may be used to detect QTc-accentuating factors in real time and identify situations that cause perturbations in an infants autonomic nervous system.

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