Added value of coronary artery calcium score as an adjunct to gated SPECT for the evaluation of coronary artery disease in an intermediate-risk population.

The coronary artery calcium (CAC) score is a readily and widely available tool for the noninvasive diagnosis of atherosclerotic coronary artery disease (CAD). The aim of this study was to investigate the added value of the CAC score as an adjunct to gated SPECT for the assessment of CAD in an intermediate-risk population. METHODS: Seventy-seven prospectively recruited patients with intermediate risk (as determined by the Framingham Heart Study 10-y CAD risk score) and referred for coronary angiography because of suspected CAD underwent stress (99m)Tc-tetrofosmin SPECT myocardial perfusion imaging (MPI) and CT CAC scoring within 2 wk before coronary angiography. The sensitivity and specificity of SPECT alone and of the combination of the 2 methods (SPECT plus CAC score) in demonstrating significant CAD (>/=50% stenosis on coronary angiography) were compared. RESULTS: Forty-two (55%) of the 77 patients had CAD on coronary angiography, and 35 (45%) had abnormal SPECT results. The CAC score was significantly higher in subjects with perfusion abnormalities than in those who had normal SPECT results (889 +/- 836 [mean +/- SD] vs. 286 +/- 335; P < 0.0001). Similarly, with rising CAC scores, a larger percentage of patients had CAD. Receiver-operating-characteristic analysis showed that a CAC score of greater than or equal to 709 was the optimal cutoff for detecting CAD missed by SPECT. SPECT alone had a sensitivity and a specificity for the detection of significant CAD of 76% and 91%, respectively. Combining SPECT with the CAC score (at a cutoff of 709) improved the sensitivity of SPECT (from 76% to 86%) for the detection of CAD, in association with a nonsignificant decrease in specificity (from 91% to 86%). CONCLUSION: The CAC score may offer incremental diagnostic information over SPECT data for identifying patients with significant CAD and negative MPI results.     

Late effects in 164 patients with rhabdomyosarcoma of the bladder/prostate region: a report from the international workshop

PURPOSE: We determined the late sequelae in children and adolescents with rhabdomyosarcoma of the bladder/prostate treated in the United States, Canada and selected Western European countries, primarily France, Germany, Italy and the United Kingdom, from 1979 to 1998. MATERIALS AND METHODS: We used a data collection form to record data from patient records available at the group statistical centers. RESULTS: A total of 164 patient charts had sufficient data available to be included in the study. Median patient age at diagnosis was 2.4 years. Median length of followup was approximately 8 years (range 3 to 24). Of the patients with available data 78 did not undergo cystectomy, 49 underwent partial cystectomy and 34 underwent complete cystectomy. Urinary continence was assessed at age 6 years or older in 62 patients who did not undergo cystectomy. Of these patients 43 (69%) were continent, 16 had nocturnal incontinence and 9 had diurnal incontinence. Of 44 patients who underwent partial cystectomy and had pertinent followup data 32 (73%) were continent, and 12 had nocturnal and/or diurnal incontinence. Only 11 patients underwent urodynamic investigation. Other nephrourological complications consisted of 3 or more urinary tract infections in 29 of 53 patients, abnormal renal function in 19 of 48 (tubulopathy 14, increased creatinine/blood urea nitrogen 5), chronic hematuria in 13 of 51 and hydronephrosis in 8 of 54 with available data. Vesicoureteral reflux, urinary stones and bowel problems were infrequent. CONCLUSIONS: Of the patients 48% had a relatively intact bladder after biopsy only. However, 31% of patients 6 years or older had some urinary incontinence, as did 27% of patients who had undergone partial cystectomy. In addition, 55% of all patients had 3 or more urinary tract infections, 40% had decreased renal function and 25% had chronic hematuria. Other complications were present in 15% or less of the patients with available data.     

Structural epicardial disease and microvascular function are determinants of an abnormal longitudinal myocardial blood flow difference in cardiovascular risk individuals as determined with PET/CT

Background

The aim of this study was to determine whether epicardial structural disease may affect the manifestation of a longitudinal decrease in myocardial blood flow (MBF) or MBF difference during hyperemia in cardiovascular risk individuals, and its dependency on the flow increase.

Methods and Results

In 54 cardiovascular risk individuals (at risk) and in 26 healthy controls, MBF was measured with ¹³N-ammonia and PET/CT in mL/g/min at rest and during dipyridamole stimulation. Computed tomography coronary angiography (CTA) was performed using a 64-slice CT of a PET/CT system. Absolute MBFs during dipyridamole stimulation were mildly lower in the mid-distal than in the mid-LV myocardium in controls (2.20 ± .51 vs 2.29 ± .51, P < .0001), while it was more pronounced in at risk with normal and abnormal CTA (1.56 ± .42 vs 1.91 ± .46 and 1.18 ± .34 vs 1.51 ± .40 mL/g/min, respectively, P < .0001), resulting in a longitudinal MBF difference that was highest in at risk with normal CTA, intermediate in at risk abnormal CTA, and lowest in controls (.35 ± .16 and .22 ± .09 vs .09 ± .04 mL/g/min, respectively, P < .0001). On multivariate analysis, log-CCS and mid-LV hyperemic MBF increase, indicative of microvascular function, were independent predictors of the observed longitudinal MBF difference (P ≤ .004 by ANOVA).

Conclusions

Epicardial structural disease and microvascular function are important determinants of an abnormal longitudinal MBF difference as determined with PET/CT.     

Patellofemoral joint contact forces during activities with high knee flexion

The patellofemoral (PF) joint plays an essential role in knee function, but little is known about the in vivo loading conditions at the joint. We hypothesized that the forces at the PF joint exceed the tibiofemoral (TF) forces during activities with high knee flexion. Motion analysis was performed in two patients with telemetric knee implants during walking, stair climbing, sit‐to‐stand, and squat. TF and PF forces were calculated using a musculoskeletal model, which was validated against the simultaneously measured in vivo TF forces, with mean errors of 10% and 21% for the two subjects. The in vivo peak TF forces of 2.9–3.4 bodyweight (BW) varied little across activities, while the peak PF forces showed significant variability, ranging from less than 1 BW during walking to more than 3 BW during high flexion activities, exceeding the TF forces. Together with previous in vivo measurements at the hip and knee, the PF forces determined here provide evidence that peak forces across these joints reach values of around 3 BW during high flexion activities, also suggesting that the in vivo loading conditions at the knee can only be fully understood if the forces at the TF and the PF joints are considered together. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:408–415, 2012     

Control of myocardial tissue components and cardiocyte organelles in pressure-overload hypertrophy of the cat right ventricle

Previous studies have demonstrated that there is a disproportionate increase in connective tissue in right ventricular myocardium subjected to pressure-overload hypertrophy associated with depressed cardiac contractility. While the myocardium is primarily responsive to load, the aim of the present study was to determine whether catecholamines also modulate the response of myocardial tissue components and cardiocyte organelles in pressure-overload-induced cardiac hypertrophy. Four experimental groups of cats were examined: (1) a sham-operated control group, (2) a group which had their pulmonary arteries banded in order to induce a pressure overload, (3) a group which had been subjected to the same pressure overload, but in addition had β-adrenoceptor blockade produced prior to and during the pressure overloading, and (4) a group which had been subjected to the same pressure overload, but in addition had α-adrenoceptor blockade produced prior to and maintained during the pressure overloading. As in our previous study, there was a significant and equivalent degree of right ventricular hypertrophy in all experimental groups with pressure overload when assessed either as the ratio of right ventricular weight to body weight or as cardiocyte cross-sectional area. At the light microscopic level, the disproportionate increase in the volume density of myocardial connective tissue seen in banded animals was completely prevented by either α- or β-adrenoceptor blockade. At the electron microscopic level, there was a reduction in the mitochondrial and myofibrillar volume fractions following β-adrenoceptor blockade. The results of this study provide evidence for a modulatory role of catecholamines in the control of myocardial connective-tissue proliferation in pressure-overload-induced cardiac hypertrophy. There is also evidence to support the role of the adrenergic nervous system in regulating cardiocyte subcellular organelles, independent of the regulation of cardiocyte size.     

Opposite effects of cortisol on consolidation of temporal sequence memory during waking and sleep

Memory functions involve three stages: encoding, consolidation, and retrieval. Modulating effects of glucocorticoids (GCs) have been consistently observed for declarative memory with GCs enhancing encoding and impairing retrieval, but surprisingly, little is known on how GCs affect memory consolidation. Studies in rats suggest a beneficial effect of GCs that were administered during postlearning wake periods, whereas in humans, cortisol impaired memory consolidation when administered during postlearning sleep. These inconsistent results raise the question whether effects of GCs critically depend on the brain state during consolidation (sleep vs. wake). Here, we compare for the first time directly the effects of cortisol on memory consolidation during postlearning sleep and wakefulness in different measures of declarative memory. Cortisol (13 mg vs. placebo) was intravenously infused during a postlearning nap or a time-matched period of wakefulness after participants had encoded neutral and emotional text material. Memory for the texts was tested (a) by asking for the contents of the texts ("item" memory) and (b) for the temporal order of the contents within the texts ("relational" memory). Neither postlearning infusion of cortisol during sleep nor during wakefulness affected retention of content words of emotional or neutral texts. Critically, however, the retention of temporal order within the texts, known to rely most specifically on the hippocampus proper within the medial-temporal lobe memory system, was distinctly improved by cortisol infusion during the wake phase but impaired by cortisol during sleep. These results point toward fundamentally different mechanisms of hippocampal memory consolidation, depending on the brain state.     

Lack of renal dopamine D5 receptors promotes hypertension

Disruption of the dopamine D(5) receptor gene in mice increases BP and causes salt sensitivity. To determine the role of renal versus extrarenal D(5) receptors in BP regulation, we performed cross-renal transplantation experiments. BP was similar between wild-type mice and wild-type mice transplanted with wild-type kidneys, indicating that the transplantation procedure did not affect BP. BP was lower among D(5)(-/-) mice transplanted with wild-type kidneys than D(5)(-/-) kidneys, demonstrating that the renal D(5) receptors are important in BP control. BP was higher in wild-type mice transplanted with D(5)(-/-) kidneys than wild-type kidneys but not significantly different from syngenic transplanted D(5)(-/-) mice, indicating the importance of the kidney in the development of hypertension. On a high-salt diet, all mice with D(5)(-/-) kidneys excreted less sodium than mice with wild-type kidneys. Transplantation of a wild-type kidney into a D(5)(-/-) mouse decreased the renal expression of AT(1) receptors and Nox-2. Conversely, transplantation of a D(5)(-/-) kidney into a wild-type mouse increased the expression of both, suggesting that both renal and extrarenal factors are important in the regulation of AT(1) receptor and Nox-2 expression. These results highlight the role of renal D(5) receptors in BP homeostasis and the pathogenesis of hypertension.     

Isolated main pancreatic duct injuries spectrum and management

BACKGROUND: We present our experience with the rare injury of isolated major pancreatic duct disruption. METHODS: From 1997 to 2003, 3 females and 13 males whose age ranged from 4 to 46 years were identified. Stabs caused 2 and blunt trauma 14 injuries. Nine presented acutely. Delay occurred in 7 patients, 6 with pseudocysts and 1 with infected pancreatic necrosis. RESULTS: Nine cases were managed in the acute phase: 6 by splenic-preserving distal pancreatectomy and 2 by distal pancreatico-enteric anastomosis; 1 was drained. A small pseudocyst and transient pancreatic fistula were the only complications. The 6 cases with pseudocysts were managed endoscopically. Five were stented and 1 was drained without stent. Four had resolution. Two had stent cyst migration. One required a pancreaticojejunostomy and another distal pancreatectomy. One patient died of infected pancreatic necrosis. Long-term outcome could not be assessed. CONCLUSION: In the acute situation, resection or distal pancreatico-enteric anastomoses are attainable with low morbidity. Endoscopic pseudocyst management options are feasible, with good short-term resolution. Giant cysts may be better managed operatively.