Automatic extraction of forward stroke volume using dynamic PET/CT: a dual-tracer and dual-scanner validation in patients with heart valve disease

Background

The aim of this study was to develop and validate an automated method for extracting forward stroke volume (FSV) using indicator dilution theory directly from dynamic positron emission tomography (PET) studies for two different tracers and scanners.

Methods

35 subjects underwent a dynamic ¹¹C-acetate PET scan on a Siemens Biograph TruePoint-64 PET/CT (scanner I). In addition, 10 subjects underwent both dynamic ¹⁵O-water PET and ¹¹C-acetate PET scans on a GE Discovery-ST PET/CT (scanner II). The left ventricular (LV)-aortic time-activity curve (TAC) was extracted automatically from PET data using cluster analysis. The first-pass peak was isolated by automatic extrapolation of the downslope of the TAC. FSV was calculated as the injected dose divided by the product of heart rate and the area under the curve of the first-pass peak. Gold standard FSV was measured using phase-contrast cardiovascular magnetic resonance (CMR).

Results

FSV_PET correlated highly with FSV_CMR (r = 0.87, slope = 0.90 for scanner I, r = 0.87, slope = 1.65, and r = 0.85, slope = 1.69 for scanner II for ¹⁵O-water and ¹¹C-acetate, respectively) although a systematic bias was observed for both scanners (p < 0.001 for all). FSV based on ¹¹C-acetate and ¹⁵O-water correlated highly (r = 0.99, slope = 1.03) with no significant difference between FSV estimates (p = 0.14).

Conclusions

FSV can be obtained automatically using dynamic PET/CT and cluster analysis. Results are almost identical for ¹¹C-acetate and ¹⁵O-water. A scanner-dependent bias was observed, and a scanner calibration factor is required for multi-scanner studies. Generalization of the method to other tracers and scanners requires further validation.

Cardiac abnormalities assessed by non-invasive techniques in patients with newly diagnosed idiopathic inflammatory myopathies

OBJECTIVES

Knowledge of cardiac involvement in idiopathic inflammatory myopathies (IIM) is limited, especially in the early stage of disease. The objective of the present study was to perform a controlled evaluation of cardiac abnormalities in newly diagnosed, untreated patients with idiopathic inflammatory myopathies (IIM) by means of non-invasive techniques.

METHODS

Fourteen patients with IIM (8 polymyositis, 4 dermatomyositis, 2 cancer-associated dermatomyositis) and 14 gender- and age- matched healthy control subjects were investigated. Participant assessments included a cardiac questionnaire, cardiac troponin-I (TnI), electrocardiogram (standard 12-lead and 48-h Holter monitoring), echocardiography with tissue Doppler measures, cardiac magnetic resonance (CMR) imaging with T2 mapping and semi-quantitative (99m)technetium pyrophosphate ((99m)Tc-PYP) scintigraphy.

RESULTS

Dyspnoea was present in 8 (57%) of the patients compared to none of the controls (p<0.01). Median levels of TnI in patients and controls were 20 ng/L and 6 ng/L, respectively (p=0.06). QTc intervals were prolonged in the patient group (p=0.01). Two patients had systolic dysfunction, and one diastolic dysfunction. The myocardial (99m)Tc-PYP uptake and CMR results differed between patients and controls, albeit not with statistical significance. Overall, cardiac abnormalities were demonstrated in 9 (64%) of the patients versus 2 (14%) of the controls (p=0.02).

CONCLUSIONS

Cardiac abnormalities assessed by TnI, ECG or imaging modalities were significantly more common in newly diagnosed, treatment naïve patients with IIM compared to healthy control subjects. These abnormalities, although subclinical, may indicate that myocardial involvement is common in patients and calls for larger controlled studies and further investigations of the prognostic implications of this finding.

Sensible method for updating motif instances in an increased biological network

A network motif is defined as an over-represented subgraph pattern in a network. Network motif based techniques have been widely applied in analyses of biological networks such as transcription regulation networks (TRNs), protein-protein interaction networks (PPIs), and metabolic networks. The detection of network motifs involves the computationally expensive enumeration of subgraphs, NP-complete graph isomorphism testing, and significance testing through the generation of many random graphs to determine the statistical uniqueness of a given subgraph. These computational obstacles make network motif analysis unfeasible for many real-world applications. We observe that the fast growth of biotechnology has led to the rapid accretion of molecules (vertices) and interactions (edges) to existing biological network databases. Even with a small percentage of additions, revised networks can have a large number of differing motif instances. Currently, no existing algorithms recalculate motif instances in 'updated' networks in a practical manner. In this paper, we introduce a sensible method for efficiently recalculating motif instances by performing motif enumeration from only updated vertices and edges. Preliminary experimental results indicate that our method greatly reduces computational time by eliminating the repeated enumeration of overlapped subgraph instances detected in earlier versions of the network. The software program implementing this algorithm, defined as SUNMI (Sensible Update of Network Motif Instances), is currently a stand-alone java program and we plan to upgrade it as a web-interactive program that will be available through http://faculty.washington.edu/kimw6/research.htm in near future. Meanwhile it is recommended to contact authors to obtain the stand-alone SUNMI program.

Tree branch-shaped cupric oxide for highly effective photoelectrochemical water reduction

Highly efficient tree branch-shaped CuO photocathodes are fabricated using the hybrid microwave annealing process with a silicon susceptor within 10 minutes. The unique hierarchical, one-dimensional structure provides more facile charge transport, larger surface areas, and increased crystallinity and crystal ordering with less defects compared to irregular-shaped CuO prepared by conventional thermal annealing. As a result, the photocathode fabricated with the tree branch-shaped CuO produces an unprecedently high photocurrent density of -4.4 mA cm(-2) at 0 VRHE under AM 1.5 G simulated sunlight compared to -1.44 mA cm(-2) observed for a photocathode fabricated by thermal annealing. It is also confirmed that stoichiometric hydrogen and oxygen are produced from photoelectrochemical water splitting on the tree branch-shaped CuO photocathode and a platinum anode.

AMPKα, C/EBPβ, CPT1β, GPR43, PPARγ, and SCD Gene Expression in Single- and Co-cultured Bovine Satellite Cells and Intramuscular Preadipocytes Treated with Palmitic, Stearic, Oleic, and Linoleic Acid

We previously demonstrated that bovine subcutaneous preadipocytes promote adipogenic gene expression in muscle satellite cells in a co-culture system. Herein we hypothesize that saturated fatty acids would promote adipogenic/lipogenic gene expression, whereas mono- and polyunsaturated fatty acids would have the opposite effect. Bovine semimembranosus satellite cells (BSC) and intramuscular preadipocytes (IPA) were isolated from crossbred steers and cultured with 10% fetal bovine serum (FBS)/Dulbecco’s Modified Eagle Medium (DMEM) and 1% antibiotics during the 3-d proliferation period. After proliferation, cells were treated for 3 d with 3% horse serum/DMEM (BSC) or 5% FBS/DMEM (IPA) with antibiotics. Media also contained 10 μg/mL insulin and 10 μg/mL pioglitazone. Subsequently, differentiating BSC and IPA were cultured in their respective media with 40 μM palmitic, stearic, oleic, or linoleic acid for 4 d. Finally, BSC and IPA were single- or co-cultured for an additional 2 h. All fatty acid treatments increased (p = 0.001) carnitine palmitoyltransferase-1 beta (CPT1β) gene expression, but the increase in CPT1β gene expression was especially pronounced in IPA incubated with palmitic and stearic acid (6- to 17- fold increases). Oleic and linoleic acid decreased (p = 0.001) stearoyl-CoA desaturase (SCD) gene expression over 80% in both BSC and IPA. Conversely, palmitic and stearic acid increased SCD gene expression three fold in co-cultured in IPA, and stearic acid increased AMPKα gene expression in single- and co-cultured BSC and IPA. Consistent with our hypothesis, saturated fatty acids, especially stearic acid, promoted adipogenic and lipogenic gene expression, whereas unsaturated fatty acids decreased expression of those genes associated with fatty acid metabolism.

The prognostic significance of pretreatment [18F]FDG-PET/CT imaging in patients with uterine cervical cancer: preliminary results

PURPOSE OF INVESTIGATION

To evaluate the prognostic significance of positron emission tomography/computed tomography (PET/CT) in patients diagnosed with cervical cancer.

MATERIALS AND METHODS

Patients with cervical cancer in FIGO Stages IB1 to IVB were imaged with PET/CT prior to treatment during one of the staging work-ups. The patients were observed for a median of 31.4 months (range, six to 89 months) after the initial treatment. The standardized uptake value (SUV) max of the primary cervical tumor mass was compared with the prognostic factors. RESULTs: A total of 81 patients who were primarily treated with radical hysterectomy (RH, n = 45) or concurrent chemoradiation (CCRT, n = 36) were analyzed. Multivariate analysis indicated that larger tumor size (> 4 cm, OR 8.694, 95% CI, 1.638-46.146), deep stromal invasion (≥ 1 cm, OR 7.249, 95% CI, 1.141-46.039) by the primary tumor, and pathologically confirmed pelvic lymph node involvement (positive, OR 14.586, 95% CI, 2.072-102.674) were significantly associated with recurrence after treatment. However, pretreatment SUVmax was not a significant independent predictor of disease recurrence (OR 1.058, 95% CI, 0.255-4.398).

CONCLUSION

[18F]Fluorodeoxyglucose (FDG) uptake by the primary tumor showed a significant association with several risk factors that have been identified as treatment predictors. However, a high pretreatment SUVmax was not predictive of recurrence in uter- ine cervical cancer patients.

Catalytic CO2 hydrogenation to formic acid over carbon nanotube-graphene supported PdNi alloy catalysts

Pure formic acid was produced via CO₂ hydrogenation over a heterogeneous PdNi alloy catalyst on carbon nanotube-graphene support in water solvent without a base additive.

Incidental renal cell carcinoma originating from a native kidney after en-bloc resection for adrenal carcinoma in a kidney transplant recipient

BACKGROUND

Renal transplantation is the best treatment for patients with end-stage renal disease. Although there is significantly increased risk of malignancy after renal transplantation, carcinoma of the native kidney is very rare, and moreover, the risk of endocrinologic malignancy after renal transplantation is lower than in the general population and adrenal cortical carcinoma extremely rare. We report a case of incidental renal cell carcinoma originating from a native kidney after en-bloc resection for adrenal carcinoma in a kidney transplant recipient.

CASE REPORT

A 57 year-old male patient had undergone living-donor kidney transplantation for chronic renal failure from hypertension 15 years earlier and had a right adrenal tumor diagnosed on surveillance abdomen-pelvis computerized tomography. Based on 24-hour catecholamine laboratory findings, nonfunctioning tumor was suspected. The planned en-bloc resection of right adrenal gland and right native kidney combining the perirenal tissue and Gerota fascia was performed, because the tumor was suspicious for malignancy and could possibly invade the perirenal tissue or right kidney. On the final pathology, combined adrenal cortical carcinoma and incidental renal cell carcinoma was confirmed. Renal cell carcinoma was papillary, type I, and stage T1N0M0. Adrenal cortical carcinoma was 7.6 × 6.5 cm in size, had marked nuclear atypia, and was grade IV/IV. Mitotic counts were >10 per high-power field, but it had no capsular invasion or vascular invasion, and free resection margin was confirmed. In the preoperative period, he had taken immunosuppressants FK506 and mycophenolate sodium, but after combined carcinomas were confirmed, the regimen of combination of immunosuppressants was changed to sirolimus with low-dose FK506 and half-dose mycophenolate sodium.

Effects of Cordyceps militaris on the growth of rumen microorganisms and in vitro rumen fermentation with respect to methane emissions

This experiment was designed to investigate the effects of different concentrations (0.00, 0.10, 0.15, 0.20, 0.25, and 0.30 g/L) of dried Cordyceps militaris mushroom on in vitro anaerobic ruminal microbe fermentation and methane production using soluble starch as a substrate. Ruminal fluids were collected from Korean native cattle, mixed with phosphate buffer (1:2), and incubated anaerobically at 38 °C for 3, 6, 9, 12, 24, 36, 48, and 72 h. The addition of C. militaris significantly increased total volatile fatty acid and total gas production. The molar proportion of acetate was decreased and that of propionate was increased, with a corresponding decrease in the acetate:propionate ratio. As the concentration of C. militaris increased from 0.10 to 0.30 g/L, methane and hydrogen production decreased. The decrease in methane accumulation relative to the control was 14.1, 22.0, 24.9, 39.7, and 40.9% for the 0.10, 0.15, 0.20, 0.25, and 0.30 g/L treatments, respectively. Ammonia-N concentration and numbers of live protozoa decreased linearly with increasing concentrations of C. militaris. The pH of the medium significantly decreased at the highest level of C. militaris compared with the control. In conclusion, C. militaris stimulated mixed ruminal microorganism fermentation and inhibited methane production in vitro. Therefore, C. militaris could be developed as a novel compound for antimethanogenesis.

Effect of indigenous herbs on growth, blood metabolites and carcass characteristics in the late fattening period of hanwoo steers

This study was conducted to evaluate the effects of indigenous herbal supplements on growth, blood metabolites and carcass characteristics in the late fattening period of Hanwoo steers. In a 6 month feeding trial, thirty Hanwoo steers (647±32 kg) were allotted to one of 5 treatment groups, control (basal diet contained lasalocid), licorice, clove, turmeric and silymarin, with six steers per pen. All groups received ad libitum concentrate and 1 kg rice straw/animal/d throughout the feeding trial. Blood samples were collected at the beginning, middle, and the end of the experiment and the steers were slaughtered at the end. Blood glucose, triglyceride, total protein, and albumin concentrations were higher in the turmeric treatment compared with other treatments. Blood urea nitrogen and creatinine concentrations were highest (p<0.003 and p = 0.071, respectively) in steers treated with silymarin. Alanine aminotransferase activity was lower (p<0.06) for licorice and silymarin compared with the control group. There were no alterations in serum aspartate aminotransferase and gamma glutamyltransferase activities as a consequence of herb treatments (p = 0.203 and 0.135, respectively). Final body weight, body weight gain, average dairy gain and dry matter intake were not significantly different among treatments. Yield grade, marbling score and quality grade were higher for silymarin group than those of the control group (p<0.05). Therefore, the results suggest that silymarin can be used an effective dietary supplement as an alternative to antibiotic feed additive and a productivity enhancer, providing safe and more consumer acceptable alternative to synthetic compounds during the late fattening period of steers.

Impact of acute hyperglycemia on myocardial infarct size, area at risk, and salvage in patients with STEMI and the association with exenatide treatment: results from a randomized study

Hyperglycemia upon hospital admission in patients with ST-segment elevation myocardial infarction (STEMI) occurs frequently and is associated with adverse outcomes. It is, however, unsettled as to whether an elevated blood glucose level is the cause or consequence of increased myocardial damage. In addition, whether the cardioprotective effect of exenatide, a glucose-lowering drug, is dependent on hyperglycemia remains unknown. The objectives of this substudy were to evaluate the association between hyperglycemia and infarct size, myocardial salvage, and area at risk, and to assess the interaction between exenatide and hyperglycemia. A total of 210 STEMI patients were randomized to receive intravenous exenatide or placebo before percutaneous coronary intervention. Hyperglycemia was associated with larger area at risk and infarct size compared with patients with normoglycemia, but the salvage index and infarct size adjusting for area at risk did not differ between the groups. Treatment with exenatide resulted in increased salvage index both among patients with normoglycemia and hyperglycemia. Thus, we conclude that the association between hyperglycemia upon hospital admission and infarct size in STEMI patients is a consequence of a larger myocardial area at risk but not of a reduction in myocardial salvage. Also, cardioprotection by exenatide treatment is independent of glucose levels at hospital admission. Thus, hyperglycemia does not influence the effect of the reperfusion treatment but rather represents a surrogate marker for the severity of risk and injury to the myocardium.

Imaging of carotid artery vessel wall edema using T2-weighted cardiovascular magnetic resonance

BACKGROUND

Atherothrombosis remains a major health problem in the western world, and carotid atherosclerosis is an important contributor to embolic ischemic strokes. It remains a clinical challenge to identify rupture-prone atherosclerotic plaques before clinical events occur. Inflammation, endothelial injury and angiogenesis are features of vulnerable plaques and may all be associated with plaque edema. Therefore, vessel wall edema, which can be detected by 2D T2-weighted cardiovascular magnetic resonance (CMR), may be used as a dynamic marker of disease activity in the atherosclerotic plaque. However, 2D imaging is limited by low spatial resolution in the slice-select direction compared to 3D imaging techniques. We sought to investigate the ability of novel 3D techniques to detect edema induced in porcine carotid arteries by acute balloon injury compared to conventional 2D T2-weighted black-blood CMR.

METHODS

Edema was induced unilaterally by balloon overstretch injury in the carotid artery of nine pigs. Between one to seven hours (average four hours) post injury, CMR was performed using 2D T2-weighted short-tau inversion recovery (T2-STIR), 3D volumetric isotropic turbo spin echo acquisition (VISTA) and 3D T2 prepared gradient-echo (T2prep-GE). The CMR images were compared in terms of signal-to-noise ratio (SNR) and contrast-to-noise (CNR) ratio. Furthermore, the presence of vessel wall injury was validated macroscopically by means of Evans Blue dye that only enters the injured vessel wall.

RESULTS

All three imaging sequences classified the carotid arteries correctly compared to Evans Blue and all sequences demonstrated a significant increase in SNR of the injured compared to the non-injured carotid vessel wall (T2-STIR, p = 0.002; VISTA, p = 0.004; and T2prep-GE, p = 0.003). There was no significant difference between sequences regarding SNR and CNR.

CONCLUSION

The novel 3D imaging sequences VISTA and T2prep-GE perform comparably to conventional 2D T2-STIR in terms of detecting vessel wall edema. The improved spatial coverage of these 3D sequences may facilitate visualization of vessel wall edema to enable detection and monitoring of vulnerable carotid atherosclerotic plaques.

Laparoendoscopic single-site surgery (LESS) for large benign adnexal tumors: one surgeon's experience over one-year period

OBJECTIVE

To present the authors' experience with laparoendoscopic single-site surgery (LESS) surgery for large benign adnexal tumors and to compare the removal time of resected specimen with that of conventional laparoscopy.

STUDY DESIGN

Ten consecutive patients underwent LESS for huge adnexal tumors at Myongjil Hospital, Korea between March 2011 and July 2012. A modified open Hasson technique was used to gain access to the abdominal cavity. The single-port device was inserted trans-umbilically into the wound opening. After suction of large amount of fluid content, LESS salpingo-oophorectomy was performed. The resected adnexal specimen was placed into a LapBag for removal out of the abdominal cavity. The authors compared the removal time of resected specimen between LESS and previously performed conventional laparoscopy for large benign adnexal tumors.

RESULTS

The adnexal tumors in this study were all very large cystic tumors reaching near or over the umbilicus. It took less than ten minutes for the removal of the resected adnexal tumors in all LESS cases (three to ten minutes), much less time than that of the conventional laparoscopy (usually ten to 17 minutes).

CONCLUSION

LESS for large benign adnexal tumors is feasible and removal of resected adnexal tumor is easier than conventional laparoscopic surgery.

Multifocal microinvasive squamous cell carcinoma with extensive spread of squamous cell carcinoma in situ (CIS) into the uterine corpus, vagina, and left salpinx diagnosed five years after conization of cervical CIS

BACKGROUND

Multifocal microinvasive squamous cell carcinoma (SCC) with extensive spread of squamous cell carcinoma in situ (CIS) into the uterine corpus, salpinx, and vagina is extremely unusual.

CASE

The authors present a case of 69-year-old woman with hydrometra who was found to have multifocal microinvasive SCC in the endometrium. The CIS had spread superficially throughout the entire endometrium up to the fundus, completely replacing the epithelium. The uterine cervix, vaginal surface and left salpingeal mucosa were involved. She had previously undergone conization due to cervical CIS five years prior. The pathologic reports showed clear resection margins at that time.

CONCLUSION

The present case suggests that CIS in the endometrium spread back to the cervix and vagina, although the definite origin of the first CIS was not determined.

Abstract P2-02-08: MRI in predicting pathological response of breast cancer after neoadjuvant chemotherapy: Correlation with tumor size and morphology changes

PURPOSE

Contrast enhanced MR imaging is widely used to monitor the response of neoadjuvant chemotherapy (NAC) in breast cancer patients. The objectives of the study are 1) to assess the response of neoadjuvant chemotherapy (NAC) according to molecular biomarker status using MRI, 2) to evaluation of changes in morphological variation, and 3) to compare MR imaging-pathological size discrepancy depending on molecular biomarker status.

MATERIALS AND METHODS

Between May 2007 and March 2012, a total of 47 patients (age range, 34-65 years; mean age, 48 years) underwent NAC prior to surgery. Among them, 34 patients who performed MRI before and after NAC were enrolled. The extent of the lesion is measured by longest diameter. The response to NAC was calculated as reduction rate between pre NAC MRI and post NAC MRI. Histological grading system - Miller and Payne grade - was also recorded. Patients were divided into subgroups based on human epidermal growth factor receptor 2 (HER2), hormone receptors (HRs), and the proliferation marker Ki-67 status. The morphologic changes were classified into 1) concentric reduction, 2) fragmentation, 3) non-mass like, and 4) architectural distortion.

RESULTS

Total of 34 lesions from 34 patients were included. Among them, 12 lesions (35.3%) were pathologically proven to have no residual tumor (Miller and Payne grade 5). The mean MR reduction rate tended to be higher in HER2-positive (62.7%) and triple negative subgroups (61.9%) than HR-positive subgroup (47.7%). The mean MR imaging-pathologic size discrepancy tended to be smaller in triple negative subgroup (0.5cm) than HER2-positive (1.2cm) and HR-positive subgroups (1.4cm). All results showed no statistical significance (P&gt;0.05). Ki-67 expression showed no significant correlations in tumor response (r = 0.17, P = 0.4) and MR imaging-pathologic size discrepancy (r = 0.1, P = 0.6). The majority of morphologic change is concentric reduction (57.6%). MRI is tended to overestimate residual size of the lesion (62.5%)

CONCLUSION

HER2-positive and triple negative subgroups showed relatively better response. Tumors were most likely to response in the manner of concentric reduction. The mean MR imaging-pathologic size discrepancy tended to be smaller in triple negative subgroup. MRI is reliable method in predicting histopathological response to NAC, but is more likely to overestimate the residual size of the lesion.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-02-08.

The impact of saddle embolism on the major adverse event rate of patients with non-high-risk pulmonary embolism

OBJECTIVE

Wider application of CT angiography (CTA) improves the diagnosis of acute pulmonary embolism (PE). It also permits the visualisation of saddle embolism (SE), namely thrombi, which are located at the bifurcation of the main pulmonary artery. The aim of this study was to assess the prevalence of SE and whether SE predicts a complicated clinical course in patients with non-high-risk PE.

METHODS

In total, 297 consecutive patients with non-high-risk PE confirmed using CTA in the emergency department were studied. The presence of SE and its ability to predict the occurrence of major adverse events (MAEs) within 1 month were determined.

RESULTS

Of the 297 patients, 27 (9.1%) had an SE. The overall mortality at 1 month was 12.5%; no significant difference was observed between the SE and non-SE groups (18.5% vs 11.9%, p=0.32). However, patients with SE were more likely to receive thrombolytic therapy (29.6% vs 8.1%, p<0.01) and had significantly more MAEs (59.3% vs 25.6%, p<0.01).

CONCLUSION

At the time of diagnosis, SE, as determined using CTA, is associated with the development of MAE within 1 month. It may be a simple method for risk stratification of patients with non-high-risk PE.

ADVANCES IN KNOWLEDGE

The prognosis of patients with SE, especially those who are haemodynamically stable, is unclear. This study shows that patients with SE, determined with CTA, is associated with the development of MAE.