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2205 citation(s) found for "Young, KM".

Variation in the Region of the Angiotensin-Converting Enzyme Gene Influences Interindividual Differences in Blood Pressure Levels in Young White Males
Fornage, Myriam , Kardia, Sharon R., Boerwinkle, Eric , Amos, Christopher I. , Sing, Charles F. , Turner, Stephen T.

Circulation | June 12, 2012 | Volume: 97 | Issue: 18 | Pages: 1773-1779

10.1161/01.cir.97.18.1773 | PMID 9603530 Get It

Background —The renin-angiotensin system regulates blood pressure through its effects on vascular tone, renal hemodynamics, and renal sodium and fluid balance. Methods and Results —Using data from a large population-based sample of 1488 siblings having a mean age of 14.8 years and belonging to the youngest generation of 583 randomly ascertained three-generation pedigrees from Rochester, Minn, we carried out variance components–based linkage analyses to evaluate the contribution of variation in four renin-angiotensin system gene regions (angiotensinogen, renin, angiotensin I–converting enzyme, and angiotensin II receptor type 1) to interindividual variation in systolic, diastolic, and mean arterial pressure. We rejected the null hypothesis that allelic variation in the region of the angiotensin-converting enzyme ( ACE ) gene does not contribute to interindividual blood pressure variability. After conditioning on measured covariates, variation in this region accounted for 0%, 13% ( P =0.04), and 16% ( P =0.04) of the interindividual variance in systolic, diastolic, and mean arterial pressures, respectively. These estimates were even greater in a subset of subjects with a positive family history of hypertension (0%, 29% [ P =0.005], and 32% [ P <0.005], respectively). In sex-specific analyses, genetic variation in the region of the ACE gene significantly influenced interindividual blood pressure variation in males (37% for SBP [ P =0.03], 38% for DBP [ P =0.04], and 53% for MAP [ P <0.005]) but not in females. Conclusions —Although it is possible that variation in a gene near the ACE gene may explain the observed results, knowledge about the physiological involvement of ACE in blood pressure regulation supports the proposition that the ACE gene itself influences blood pressure variability in a sex-specific manner.
Secular Trends in Cardiac Transplant Recipient and Donor Management in the United States, 1990 to 1994
Rodeheffer, Richard J. , Naftel, David C., Stevenson, Lynne W. , Porter, Charles , Miller, Leslie W., Kenzora, Joseph L., Haas, Garrie J. , Bourge, Robert C. , Mehra, Mandeep R. , Young, James B. , Kirklin, James K. , Mehra, Mandeep R

Circulation | June 12, 2012 | Volume: 94 | Issue: 11 | Pages: 2883-2889

10.1161/01.cir.94.11.2883 | PMID 8941117 Get It

Background The growth of the US cardiac transplant waiting list has outpaced the increase in donors, resulting in a widening gap between the number of waiting recipients and available donors. These trends have generated concern that longer waiting times may result in more patients deteriorating to urgent status and that transplanting only patients who are in an advanced state of decompensation will reduce posttransplant survival. Furthermore, the shortage of donors may result in extending the guidelines for donor acceptability to a degree that increases graft failure and posttransplant mortality. We measured these secular trends in the Cardiac Transplant Research Database to provide current data on time-dependent changes in US cardiac transplant practice and survival. Methods and Results At the time of this analysis, the Cardiac Transplant Research Database included all 2749 patients transplanted from January 1, 1990, to June 30, 1994, in the 25 participating transplant centers. During this 4.5-year period, the median waiting time for recipients who received a transplant increased from 2.7 to 3.5 months ( P <.0001), and the proportion of recipients whose status was urgent at transplantation increased from 41% to 60% ( P <.0001). Donor ischemic time increased from 150 to 166 minutes ( P <.0001), and the proportion of donors requiring pressor support increased from 68% to 85% ( P <.0001). Despite these changes in practice, the 1-year survival rate remained constant at 84% during this 4.5-year interval. There was no significant difference in 1-year survival rate between urgent status patients (83%) and nonurgent status patients (85%) ( P =.08). Conclusions The widening gap between the number of waiting recipients and the number of donors has resulted in a continuing trend toward transplanting urgent status recipients and to a liberalization of donor acceptance criteria. Despite these changes, posttransplant survival has remained constant.
Influence of the Menstrual Cycle on Sympathetic Activity, Baroreflex Sensitivity, and Vascular Transduction in Young Women
Minson, Christopher T. , Halliwill, John R. , Young, Tamica M., Joyner, Michael J. , Joyner, Michael J

Circulation | June 11, 2012 | Volume: 101 | Issue: 8 | Pages: 862-868

10.1161/01.cir.101.8.862 | PMID 10694525 Get It

Background —Our goal was to test sympathetic and cardiovagal baroreflex sensitivity and the transduction of sympathetic traffic into vascular resistance during the early follicular (EF) and midluteal (ML) phases of the menstrual cycle. Methods and Results —Sympathetic baroreflex sensitivity was assessed by lowering and raising blood pressure with intravenous bolus doses of sodium nitroprusside and phenylephrine. It was defined as the slope relating muscle sympathetic nerve activity (MSNA; determined by microneurography) and diastolic blood pressure. Cardiovagal baroreflex sensitivity was defined as the slope relating R-R interval and systolic blood pressure. Vascular transduction was evaluated during ischemic handgrip exercise and postexercise ischemia, and it was defined as the slope relating MSNA and calf vascular resistance (determined by plethysmography). Resting MSNA (EF, 1170±151 U/min; ML, 2252±251 U/min; P <0.001) and plasma norepinephrine levels (EF, 240±21 pg/mL; ML, 294±25 pg/mL; P =0.025) were significantly higher in the ML than in the EF phase. Furthermore, sympathetic baroreflex sensitivity was greater during the ML than the EF phase in every subject (MSNA/diastolic blood pressure slopes: EF, −4.15; FL, −5.42; P =0.005). No significant differences in cardiovagal baroreflex sensitivity or vascular transduction were observed. Conclusions —The present study suggests that the hormonal fluctuations that occur during the normal menstrual cycle may alter sympathetic outflow but not the transduction of sympathetic activity into vascular resistance.
Gamma Knife surgery for the management of glomus tumors: a multicenter study
Sheehan, Jason P. , Tanaka, Shota , Link, Michael J. , Pollock, Bruce E. , Mathieu, David , Duma, Christopher , Young, A. Byron, Kaufmann, Anthony M. , McBride, Heyoung L., Weisskopf, Peter A., Xu, Zhiyuan , Kano, Hideyuki , Lunsford, L. Dade , Kondziolka, Douglas , Yang, Huai‐Che , Mathieu, David

Journal of Neurosurgery | June 8, 2012 | Volume: 117 | Issue: 2 | Pages: 246-254

10.3171/2012.4.jns11214 | PMID 22680240 Get It

Object Glomus tumors are rare skull base neoplasms that frequently involve critical cerebrovascular structures and lower cranial nerves. Complete resection is often difficult and may increase cranial nerve deficits. Stereotactic radiosurgery has gained an increasing role in the management of glomus tumors. The authors of this study examine the outcomes after radiosurgery in a large, multicenter patient population. Methods Under the auspices of the North American Gamma Knife Consortium, 8 Gamma Knife surgery centers that treat glomus tumors combined their outcome data retrospectively. One hundred thirty-four patient procedures were included in the study (134 procedures in 132 patients, with each procedure being analyzed separately). Prior resection was performed in 51 patients, and prior fractionated external beam radiotherapy was performed in 6 patients. The patients' median age at the time of radiosurgery was 59 years. Forty percent had pulsatile tinnitus at the time of radiosurgery. The median dose to the tumor margin was 15 Gy. The median duration of follow-up was 50.5 months (range 5–220 months). Results Overall tumor control was achieved in 93% of patients at last follow-up; actuarial tumor control was 88% at 5 years postradiosurgery. Absence of trigeminal nerve dysfunction at the time of radiosurgery (p = 0.001) and higher number of isocenters (p = 0.005) were statistically associated with tumor progression–free tumor survival. Patients demonstrating new or progressive cranial nerve deficits were also likely to demonstrate tumor progression (p = 0.002). Pulsatile tinnitus improved in 49% of patients who reported it at presentation. New or progressive cranial nerve deficits were noted in 15% of patients; improvement in preexisting cranial nerve deficits was observed in 11% of patients. No patient died as a result of tumor progression. Conclusions Gamma Knife surgery was a well-tolerated management strategy that provided a high rate of long-term glomus tumor control. Symptomatic tinnitus improved in almost one-half of the patients. Overall neurological status and cranial nerve function were preserved or improved in the vast majority of patients after radiosurgery.
Global Methylation Profiling for Risk Prediction of Prostate Cancer
Mahapatra, Saswati , Klee, Eric W. , Sun, Zhifu , Jiménez, Rafael E. , Klee, George G., Tindall, Donald J., Donkena, Krishna Vanaja, Young, Charles Y.F. , Sun, Zhifu

Clinical Cancer Research | May 15, 2012 | Volume: 18 | Issue: 10 | Pages: 2882-2895

10.1158/1078-0432.ccr-11-2090 | PMID 22589488 Get It

Abstract Purpose: The aim of this study was to investigate the promoter hypermethylation as diagnostic markers to detect malignant prostate cells and as prognostic markers to predict the clinical recurrence of prostate cancer. Experimental Design: DNA was isolated from prostate cancer and normal adjacent tissues. After bisulfite conversion, methylation of 14,495 genes was evaluated using the Methylation27 microarrays in 238 prostate tissues. We analyzed methylation profiles in four different groups: (i) tumor (n = 198) versus matched normal tissues (n = 40), (ii) recurrence (n = 123) versus nonrecurrence (n = 75), (iii) clinical recurrence (n = 80) versus biochemical recurrence (n = 43), and (iv) systemic recurrence (n = 36) versus local recurrence (n = 44). Group 1, 2, 3, and 4 genes signifying biomarkers for diagnosis, prediction of recurrence, clinical recurrence, and systemic progression were determined. Univariate and multivariate analyses were conducted to predict risk of recurrence. We validated the methylation of genes in 20 independent tissues representing each group by pyrosequencing. Results: Microarray analysis revealed significant methylation of genes in four different groups of prostate cancer tissues. The sensitivity and specificity of methylation for 25 genes from 1, 2, and 4 groups and 7 from group 3 were shown. Validation of genes by pyrosequencing from group 1 (GSTP1, HIF3A, HAAO, and RARβ), group 2 (CRIP1, FLNC, RASGRF2, RUNX3, and HS3ST2), group 3 (PHLDA3, RASGRF2, and TNFRSF10D), and group 4 (BCL11B, POU3F3, and RASGRF2) confirmed the microarray results. Conclusions: Our study provides a global assessment of DNA methylation in prostate cancer and identifies the significance of genes as diagnostic and progression biomarkers of prostate cancer. Clin Cancer Res; 18(10); 2882–95. ©2012 AACR.
Treatment of Intracerebral Hematomas in Young and Middle‐aged Patients
Miller, Ross H. , Clark, Edward C., Dodge, Henry W., Clark, Edward C.

Neurology | May 13, 2012 | Volume: 5 | Issue: 8 | Pages: 567-567

10.1212/wnl.5.8.567 | PMID 13244772 Get It

Epilepsia partialis continua as an atypical presentation of cat scratch disease in a young adult
Nowakowski, Grzegorz S. , Katz, Amiram

Neurology | May 13, 2012 | Volume: 59 | Issue: 11 | Pages: 1815-1816

10.1212/01.wnl.0000036620.27344.e9 | PMID 12473786 Get It

Computerized tomography in demyelinating disease of the young
Robertson, William C., Gómez, Manuel R., Reese, David F., Okazaki, Haruo

Neurology | May 13, 2012 | Volume: 27 | Issue: 9 | Pages: 838-838

10.1212/wnl.27.9.838 | PMID 561340 Get It

Evaluation of Children With Selective Mutism and Social Phobia
Young, Brennan J., Bunnell, Brian E. , Beidel, Déborah C. , Young, Brennan J.

Behavior Modification | May 8, 2012 | Volume: 36 | Issue: 4 | Pages: 525-544

10.1177/0145445512443980 | PMID 22569579 Get It

Although children with social phobia (SP) and selective mutism (SM) present similarly in a clinical setting, it remains unclear whether children with SM are unable to speak due to overwhelming anxiety, or whether withholding speech functions as an avoidance mechanism. A total of 35 children (ages 5-12 years) with either SM ( n = 10), SP ( n = 11), or no diagnosis ( n = 14) participated in the current study. Measurements included clinician, child, and parent ratings as well as behavioral observations and psychophysiological measures. Independent evaluators and clinicians rated children with SM as more severely impaired, more anxious, and less socially effective, but the groups did not differ in self- or parent-reported anxiety. Psychophysiological measures indicated that children in the SM group experienced less arousal than other children during social interaction tasks. The authors postulate that lack of speech may serve as an avoidance mechanism and thus account for this lack of arousal.
Gonadotropin-Inhibitory Hormone (GnIH) Secretion into the Ovine Hypophyseal Portal System
Smith, J. T. , Young, I. R., Veldhuis, Johannes D. , Clarke, Iain J.

Endocrinology | May 2, 2012 | Volume: 153 | Issue: 7 | Pages: 3368-3375

10.1210/en.2012-1088 | PMID 22549225 Get It

GnIH was first identified in avian species, and there is now strong evidence that it is operant in mammals as an inhibitor of reproduction. Mammalian gonadotropin-inhibitory hormone (GnIH)-3 is encoded by the RFRP gene in neurons of the dorsomedial nucleus. These neurons project to the median eminence, predicting a role as a secreted neurohormone and regulation of the pituitary gonadotropes. To determine whether GnIH-3 is a secreted neurohormone, we measured its concentration in hypophyseal portal blood in ewes during the nonbreeding (anestrous) season and during the luteal and follicular phases of the estrous cycle in the breeding season. Paired portal and jugular blood samples were collected and plasma prepared for RIA using an ovine GnIH-3 antibody. Pulsatile GnIH-3 secretion was observed in the portal blood of all animals. Mean GnIH-3 pulse amplitude and pulse frequency was higher during the nonbreeding season. GnIH-3 was virtually undetectable in peripheral blood plasma. There was a lack of association between secretory pulses of GnIH-3 (portal) and LH (peripheral). To determine the role of secreted GnIH-3, we examined its effects on GnRH-stimulated LH secretion in hypothalamo-pituitary-disconnected ewes; a significant reduction in the LH response to GnRH was observed. Finally, to identify cellular targets in the pituitary, the expression of GnIH receptor [G protein-coupled receptor 147 (GPR147)] in fractions enriched for gonadotropes somatotropes, and lactotropes was examined; expression was observed in each cell type. These data show GnIH-3 is secreted into portal blood to act on pituitary gonadotropes, reducing the action of GnRH.