The effects of glucuronic acid and N-acetyl-D-glucosamine on in vitro fertilisation of porcine oocytes

High incidences of polyspermic penetration continue to challenge researchers during porcine in vitro fertilisation (IVF). The aim of this study was to reduce the incidence of polyspermy by increasing the perivitelline space thickness with glucuronic acid and N-acetyl-D-glucosamine (GlcNAc) supplementation during oocyte maturation. After maturation, zona pellucida and perivitelline space thicknesses, intracellular glutathione concentrations and fertilisation kinetics were measured, in addition to embryonic cleavage and blastocyst formation at 48h and 144h after IVF, respectively. There were no significant differences between the treatments for zona pellucida thickness, penetration rates, male pronuclear formation or cortical granule exocytosis. Glucuronic acid supplementation significantly increased (PPPP<0.05) of cleavage and blastocyst formation by 48 and 144h after IVF compared with all other groups. These results indicate that supplementing with 0.005mM glucuronic acid and 0.005mM GlcNAc during oocyte maturation decreases the incidence of polyspermic penetration by increasing perivitelline space thickness and improving embryo development in pigs.

Nicotinic α4β2 acetylcholine receptors and cognitive function in Parkinson's disease

BACKGROUND

Idiopathic Parkinson's disease (IPD) is characterized by the clinical motor symptoms of hypokinesia, rigidity, and tremor. Apart from these motor symptoms, cognitive deficits often occur in IPD. The positive effect of cholinesterase inhibitors on cognitive deficits in IPD and findings of earlier molecular imaging studies suggest that the cholinergic system plays an important role in the origin of cognitive decline in IPD.

METHODS

Twenty-five non-demented patients with IPD underwent a 5-[123I]iodo-3-[2(S)-2-azetidinylmethoxy]pyridine (5-I-A-85380) SPECT to visualize α4β2 nicotinic acetylcholine receptors (nAchR) and cognitive testing with the CERAD (Consortium to Establish a Registry for Alzheimer's Disease) battery to identify domains of cognitive dysfunction.

RESULTS

In the CERAD, the IPD patients exhibited deficits in non-verbal memory, attention, psychomotor velocity, visuoconstructive ability, and executive functions. After Bonferroni correction for multiple comparisons, we found significant correlations between performance of the CERAD subtests Boston Naming Test (a specific test for visual perception and for detection of word-finding difficulties) and Word List Intrusions (a specific test for learning capacity and memory for language information) vs binding of α4β2 nAchR in cortical (the right superior parietal lobule) and subcortical areas (the left thalamus, the left posterior subcortical region, and the right posterior subcortical region).

CONCLUSIONS

These significant correlations between the results of the CERAD subtests and the cerebral α4β2 nAchR density, as assessed by 5-I-A-85380 SPECT, indicate that cerebral cholinergic pathways are relevant to cognitive processing in IPD.

Nicotinic acetylcholine receptor density in cognitively intact subjects at an early stage of Parkinson's disease

We investigated in vivo brain nicotinic acetylcholine receptor (nAChR) distribution in cognitively intact subjects with Parkinson’s disease (PD) at an early stage of the disease. Fourteen patients and 13 healthy subjects were imaged with single photon emission computed tomography and the radiotracer 5-[¹²³I]iodo-3-[2(S)-2-azetidinylmethoxy]pyridine ([¹²³I]5IA). Patients were selected according to several criteria, including short duration of motor signs (<7 years) and normal scores at an extensive neuropsychological evaluation. In PD patients, nAChR density was significantly higher in the putamen, the insular cortex and the supplementary motor area and lower in the caudate nucleus, the orbitofrontal cortex, and the middle temporal gyrus. Disease duration positively correlated with nAChR density in the putamen ipsilateral (ρ = 0.56, p < 0.05) but not contralateral (ρ = 0.49, p = 0.07) to the clinically most affected hemibody. We observed, for the first time in vivo, higher nAChR density in brain regions of the motor and limbic basal ganglia circuits of subjects with PD. Our findings support the notion of an up-regulated cholinergic activity at the striatal and possibly cortical level in cognitively intact PD patients at an early stage of disease.

Targeting P-selectin by gallium-68-labeled fucoidan positron emission tomography for noninvasive characterization of vulnerable plaques: correlation with in vivo 17.6T MRI

OBJECTIVE

Nuclear imaging of active plaques still remains challenging. Advanced atherosclerotic plaques have a strong expression of P-selectin by the endothelium overlying active atherosclerotic plaques, but not on the endothelium overlying inactive fibrous plaques. We proposed a new approach for noninvasive in vivo characterization of P-selectin on active plaques based on (68)Ga-Fucoidan, which is a polysaccharidic ligand of P-selectin with a nanomolar affinity.

APPROACH AND RESULTS

(68)Ga-Fucoidan was tested for its potential to discriminate vulnerable plaques on apolipoprotein E-deficient mice receiving a high cholesterol diet by positron emission tomography and in correlation with 17.6T MRI. Furthermore, (68)Ga-Fucoidan was evaluated on endothelial cells in vitro and ex vivo on active plaques using autoradiography. The cellular uptake rate was increased ≈2-fold by lipopolysaccharide induction. Interestingly, on autoradiography, more intensive tracer accumulation at active plaques with thin fibrous caps and high-density foam cells were observed in comparison with a weaker focal uptake in inactive fibrous plaque segments (R=1.7±0.3; P<0.05) and fatty streaks (R=2.4±0.4; P<0.01). Strong uptake of radiotracer colocalized with increased P-selectin expression and high-density macrophage. Focal vascular uptake (mean of target to background ratio=5.1±0.8) of (68)Ga-Fucoidan was detected in all apolipoprotein E-deficient mice. Anatomic structures of plaque were confirmed by 17.6T MRI. The autoradiography showed a good agreement of (68)Ga-Fucoidan uptake with positron emission tomography.

CONCLUSIONS

Our data suggest that (68)Ga-Fucoidan represents a versatile imaging biomarker for P-selectin with the potential to specifically detect P-selectin expression using positron emission tomography and to discriminate vulnerable plaques in vivo.

Smoking but not cocaine use is associated with lower cerebral metabotropic glutamate receptor 5 density in humans

Long-lasting neuroadaptations in the glutamatergic corticostriatal circuitry have been suggested to be responsible for the persisting nature of drug addiction. In particular, animal models have linked the metabotropic glutamate receptor 5 (mGluR5) to drug-seeking behavior and extinction learning. Accordingly, blocking mGluR5s attenuated self-administration of cocaine and other addictive drugs in rats. How these animal findings extend to humans remains unclear. Therefore, we investigated if human cocaine users (CU) exhibit altered mGluR5 availability compared with drug-naïve control subjects. Seventeen male controls (11 smokers) and 18 male cocaine users (13 smokers) underwent positron emission tomography with (11)C-ABP688 to quantify mGluR5 availability in 12 volumes of interest in addiction-related brain areas. Drug use was assessed by self-report and quantitative hair toxicology. CU and controls did not significantly differ in regional mGluR5 availability. In contrast, smokers (n=24) showed significantly lower mGluR5 density throughout the brain (mean 20%) compared with non-smokers (n=11). In terms of effect sizes, lower mGluR5 availability was most pronounced in the caudate nucleus (d=1.50, 21%), insula (d=1.47, 20%), and putamen (d=1.46, 18%). Duration of smoking abstinence was positively associated with mGluR5 density in all brain regions of interest, indicating that lower mGluR5 availability was particularly pronounced in individuals who had smoked very recently. Specifically tobacco smoking was associated with lower mGluR5 availability in both CU and controls, while cocaine use was not linked to detectable mGluR5 alterations. These findings have important implications regarding the development of novel pharmacotherapies aimed at facilitating smoking cessation.

Quantitative cerebral perfusion imaging in children and young adults with Moyamoya disease: comparison of arterial spin-labeling-MRI and H(2)[(15)O]-PET

BACKGROUND AND PURPOSE

Cerebral perfusion assessment is important in the preoperative evaluation and postoperative follow-up of patients with Moyamoya disease. The objective of this study was to evaluate the correlation of quantitative CBF measurements performed with arterial spin-labeling-MR imaging and H2[(15)O]-PET in children and young adults with Moyamoya disease.

MATERIALS AND METHODS

Thirteen children and young adults (8 female patients; age, 9.7 ± 7.1 years; range, 1-23 years) with Moyamoya disease underwent cerebral perfusion imaging with H2[(15)O]-PET (Discovery STE PET/CT, 3D Fourier rebinning filtered back-projection, 128 × 128 × 47 matrix, 2.34 × 2.34 × 3.27 mm(3) voxel spacing) and arterial spin-labeling (3T scanner, 3D pulsed continuous arterial spin-labeling sequence, 32 axial sections, TR = 5.5 seconds, TE = 25 ms, FOV = 24 cm, 128 × 128 matrix, 1.875 × 1.875 × 5 mm(3) voxel spacing) within less than 2 weeks of each other. Perfusion of left and right anterior cerebral artery, MCA, and posterior cerebral artery territories was qualitatively assessed for arterial spin-labeling-MR imaging and H2[(15)O]-PET by 2 independent readers by use of a 3-point-Likert scale. Quantitative correlation of relative CBF with cerebellar normalization between arterial spin-labeling-MR imaging and H2[(15)O]-PET was evaluated in a volume-based approach for each vascular territory after 3D image coregistration.

RESULTS

Interreader agreement was good (κ = 0.67-0.69), and strong and significant correlations were found between arterial spin-labeling-MR imaging and H2[(15)O]-PET for both qualitative perfusion scoring (ρ = 0.77; P < .001) and quantitative perfusion assessment of relative CBF with cerebellar normalization (r = 0.67, P < .001).

CONCLUSIONS

In children and young adults with Moyamoya disease, quantitative evaluation of CBF is possible with the use of arterial spin-labeling-MR imaging without ionizing radiation or contrast injection with a good correlation to H2[(15)O]-PET after cerebellar normalization.

Shock-front injector for high-quality laser-plasma acceleration

We report the generation of stable and tunable electron bunches with very low absolute energy spread (ΔE ≈ 5 MeV) accelerated in laser wakefields via injection and trapping at a sharp downward density jump produced by a shock front in a supersonic gas flow. The peak of the highly stable and reproducible electron energy spectrum was tuned over more than 1 order of magnitude, containing a charge of 1-100 pC and a charge per energy interval of more than 10 pC/MeV. Laser-plasma electron acceleration with Ti:sapphire lasers using this novel injection mechanism provides high-quality electron bunches tailored for applications.

Dental abnormalities in Schimke immuno-osseous dysplasia

Described for the first time in 1971, Schimke immuno-osseous dysplasia (SIOD) is an autosomal-recessive multisystem disorder that is caused by bi-allelic mutations of SMARCAL1, which encodes a DNA annealing helicase. To define better the dental anomalies of SIOD, we reviewed the records from SIOD patients with identified bi-allelic SMARCAL1 mutations, and we found that 66.0% had microdontia, hypodontia, or malformed deciduous and permanent molars. Immunohistochemical analyses showed expression of SMARCAL1 in all developing teeth, raising the possibility that the malformations are cell-autonomous consequences of SMARCAL1 deficiency. We also found that stimulation of cultured skin fibroblasts from SIOD patients with the tooth morphogens WNT3A, BMP4, and TGFβ1 identified altered transcriptional responses, raising the hypothesis that the dental malformations arise in part from altered responses to developmental morphogens. To the best of our knowledge, this is the first systematic study of the dental anomalies associated with SIOD.

FLT-PET is superior to FDG-PET for very early response prediction in NPM-ALK-positive lymphoma treated with targeted therapy

The prognosis of relapsed or refractory aggressive lymphoma is poor. The huge variety of currently evolving targeted treatment approaches would benefit from tools for early prediction of response or resistance. We used various ALK-positive anaplastic large cell lymphoma (ALCL) cell lines to evaluate two inhibitors, the HSP90 inhibitor NVP-AUY922, and the mTOR inhibitor everolimus, both of which have shown to interfere with ALK-dependent oncogenic signal transduction. Their therapeutic effect was determined in vitro by MTT assay, [(18)F]fluorodeoxyglucose (FDG)- and [(18)F]fluorothymidine (FLT)-uptake, and by biochemical analysis of ALK-induced signaling. Micro-FDG- and FLT-positron emission tomography (PET) imaging studies in immunodeficient mice bearing ALCL xenotransplants were carried out with the cell lines SUDHL-1 and Karpas299 to assess early treatment response to NVP-AUY922 or everolimus in vivo. SUDHL-1 cells showed sensitivity to both inhibitors in vitro. Importantly, we detected a significant reduction of FLT-uptake in SUDHL-1 bearing animals using both inhibitors compared with baseline as early as 5 days after initiation of targeted therapy. Immunostaining showed a decrease in Ki-67 and an increase in cleaved caspase-3 staining. In contrast, FDG-uptake did not significantly decrease at early time points. Karpas299 xenotransplants, which are resistant to NVP-AUY922 and sensitive to everolimus treatment, showed an increase of mean FLT-uptake on day 2 after administration of NVP-AUY299, but a significant reduction in FLT-uptake upon everolimus treatment. In conclusion, we show that FLT-PET but not FDG-PET is able to predict response to treatment with specific inhibitors very early in the course of treatment and thus enables early prediction of treatment efficacy.

Few-cycle driven relativistically oscillating plasma mirrors: a source of intense isolated attosecond pulses

The conditions required for the production of isolated attosecond pulses from relativistically oscillating mirrors (ROM) are investigated numerically and experimentally. In simulations, carrier-envelope-phase-stabilized three-cycle pulses are found to be sufficient to produce isolated attosecond pulses, while two-cycle pulses will predominantly lead to isolated attosecond pulses even in the absence of carrier-envelope stabilization. Using a state-of-the-art laser system delivering three-cycle pulses at multiple-terawatt level, we have generated higher harmonics up to 70 eV photon energy via the ROM mechanism. The observed spectra are in agreement with theoretical expectations and highlight the potential of few-cycle-driven ROM harmonics for intense isolated attosecond pulse generation for performing extreme ultraviolet-pump extreme ultraviolet-probe experiments.

Integrated FDG-PET-CT: its role in the assessment of bone and soft tissue tumors

PURPOSE

The purpose of this study was to evaluate prospectively, whether integrated 2-deoxy-2-[(18)F]fluoro-D: -glucose positron emission tomography-computed tomography (FDG-PET-CT) is more accurate for determination musculoskeletal tumors compared with separate interpretation of CT and FDG-PET, because most of the current clinical data come from patients studied with PET.

METHODS

Eighty patients with newly diagnosed musculoskeletal tumors underwent FDG-PET-CT. CT, FDG-PET, and FDG-PET-CT were interpreted separately to determine the performance of each imaging modality.

RESULTS

Assuming that equivocal lesions are benign, performance of diagnostic tests was as follows: sensitivity, specificity and accuracy for CT alone was 81, 84, 83%, for PET 71, 82, 76, and for PET-CT 80, 83 and 86%. Assuming that equivocal lesions are malignant, sensitivity, specificity, and accuracy for CT was 61, 100, 70%, for PET 69, 100, 79, and for PET-CT 69, 100 and 79%.

CONCLUSIONS

Combined FDG-PET-CT reliably differentiates soft tissue and bone tumors from benign lesions. The value of the information provided by FDG-PET-CT for planning surgical procedures must be evaluated in further studies.

Antifungal therapy with itraconazole impairs the anti-lymphoma effects of rituximab by inhibiting recruitment of CD20 to cell surface lipid rafts

Immunotherapy with rituximab alone or in conjunction with chemotherapy has significantly improved the treatment outcome of B-cell lymphoma patients. Nevertheless, a subpopulation of patients does not respond to rituximab. The reason for treatment failure as well as the exact mechanism of action is still uncertain. The function of rituximab has long been associated with the partitioning of CD20 molecules to membrane microdomains. Here, we show that concomitant antifungal treatment with itraconazole impairs the rituximab anti-lymphoma effect both in vitro and in vivo. At the molecular level, recruitment of CD20 to lipid rafts is inhibited in the presence of itraconazole. Furthermore, calcium influx, which is crucial for rituximab-mediated cell death, was nearly completely abolished by itraconazole treatment. In contrast, the antifungal drug caspofungin did not inhibit CD20 recruitment to lipid rafts, nor did it affect calcium influx or the cytotoxic effect of rituximab. The finding that itraconazole also abolished the cytotoxic effects of other therapeutic antibodies directed against lipid raft-associated molecules (i.e., CD20 and CD52) but not those against the non-raft-associated molecule CD33 further supported our proposed mechanism of action. Our results argue that concomitant medications must be adjusted carefully to achieve optimal antitumor effects with monoclonal antibodies.

Abstract ED4-3: PET tracer for therapy monitoring

Molecular or metabolic imaging with PET plays a crucial role not only for the individual patient management but also for further validation of new therapies. The concept of using PET and [18F]fluorodeoxyglucose (FDG) for assessment of response is based on early changes in tumor glucose use which correlate to the effectiveness of a specific treatment. However, FDG-PET is a suitable surrogate marker for response prediction only in intensely FDG-avid tumors. For imaging in the context of planning of a chemotherapeutic intervention and for therapy monitoring, tracers with higher specificity are required. With the advent of molecular imaging, tumor tissue can be non-invasively characterized by imaging probes targeting biological processes such as metabolism, cell growth and migration as well as vascularization and oxygen tension. Based on such measurements signals can be defined which detect and quantitatively describe pharmacologic effects in tumor tissues within a few days after initiation of therapy. Initial results suggest that therapeutic strategies can be successfully adapted based on molecular imaging results, which are able to identify responders with improved clinical outcome. These specific and sensitive imaging signals are needed to match therapeutic targets with imaging agents addressing the same or corresponding biologic processes. Inhibiting neoangiogenesis, for example, represents an attractive therapeutic option, which benefits from imaging probes addressing molecular targets such as integrins and VEGF receptors as well as measuring perfusion and blood volume. Prior to treatment, these tracers enable to define the expression of a specific target. Alternative probes for molecular cancer imaging address metabolic key processes, such as cell proliferation ([18F]FLT), protein biosynthesis ([18F]FET, [11C]MET), neoangiogenesis ([18F]Galacto-RGD), hypoxia ([18F]FAZA), somatostatin receptor expression ([68Ga]DOTATOC), estrogen receptor expression ([18F]FES) or new concepts, such as cytokine / chemokine receptor expression ([68Ga]CPCR4). For response evalu ation, the tracer uptake has to correlate with the therapeutic effect at all imaging time points. Here, tracers with high sensitivity are required, allowing for the early assessment of therapeutic effects and response evaluation.

Citation Information: Clin Cancer Res 2010;16(7 Suppl):ED4-3

Absolute charge calibration of scintillating screens for relativistic electron detection

We report on new charge calibrations and linearity tests with high-dynamic range for eight different scintillating screens typically used for the detection of relativistic electrons from laser-plasma based acceleration schemes. The absolute charge calibration was done with picosecond electron bunches at the ELBE linear accelerator in Dresden. The lower detection limit in our setup for the most sensitive scintillating screen (KODAK Biomax MS) was 10 fC/mm(2). The screens showed a linear photon-to-charge dependency over several orders of magnitude. An onset of saturation effects starting around 10-100 pC/mm(2) was found for some of the screens. Additionally, a constant light source was employed as a luminosity reference to simplify the transfer of a one-time absolute calibration to different experimental setups.

Cyanobacterial neurotoxin BMAA in ALS and Alzheimer's disease

OBJECTIVE

The aim of this study was to screen for and quantify the neurotoxic amino acid beta-N-methylamino-L-alanine (BMAA) in a cohort of autopsy specimens taken from Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD), and non-neurological controls. BMAA is produced by cyanobacteria found in a variety of freshwater, marine, and terrestrial habitats. The possibility of geographically broad human exposure to BMAA had been suggested by the discovery of BMAA in brain tissues of Chamorro patients with ALS/Parkinsonism dementia complex from Guam and more recently in AD patients from North America. These observations warranted an independent study of possible BMAA exposures outside of the Guam ecosystem.

METHODS

Postmortem brain specimens were taken from neuropathologically confirmed cases of 13 ALS, 12 AD, 8 HD patients, and 12 age-matched non-neurological controls. BMAA was quantified using a validated fluorescent HPLC method previously used to detect BMAA in patients from Guam. Tandem mass spectrometric (MS) analysis was carried out to confirm the identification of BMAA in neurological specimens.

RESULTS

We detected and quantified BMAA in neuroproteins from postmortem brain tissue of patients from the United States who died with sporadic AD and ALS but not HD. Incidental detections observed in two out of the 24 regions were analyzed from the controls. The concentrations of BMAA were below what had been reported previously in Chamarro ALS/ Parkinsonism dementia complex patients, but demonstrated a twofold range across disease and regional brain area comparisons. The presence of BMAA in these patients was confirmed by triple quadrupole liquid chromatography/mass spectrometry/mass spectrometry.

CONCLUSIONS

The occurrence of BMAA in North American ALS and AD patients suggests the possibility of a gene/environment interaction, with BMAA triggering neurodegeneration in vulnerable individuals.

Clinical Applications of FDG PET and PET/CT in Head and Neck Cancer

18F-FDG PET plays an increasing role in diagnosis and management planning of head and neck cancer. Hybrid PET/CT has promoted the field of molecular imaging in head and neck cancer. This modality is particular relevant in the head and neck region, given the complex anatomy and variable physiologic FDG uptake patterns. The vast majority of 18F-FDG PET and PET/CT applications in head and neck cancer related to head and neck squamous cell carcinoma. Clinical applications of 18F-FDG PET and PET/CT in head and neck cancer include diagnosis of distant metastases, identification of synchronous 2nd primaries, detection of carcinoma of unknown primary and detection of residual or recurrent disease. Emerging applications are precise delineation of the tumor volume for radiation treatment planning, monitoring treatment, and providing prognostic information. The clinical role of 18F-FDG PET/CT in N0 disease is limited which is in line with findings of other imaging modalities. MRI is usually used for T staging with an intense discussion concerning the preferable imaging modality for regional lymph node staging as PET/CT, MRI, and multi-slice spiral CT are all improving rapidly. Is this review, we summarize recent literature on 18F-FDG PET and PET/CT imaging of head and neck cancer.

Dynamic laser speckle imaging of cerebral blood flow

Laser speckle imaging (LSI) based on the speckle contrast analysis is a simple and robust technique for imaging of heterogeneous dynamics. LSI finds frequent application for dynamical mapping of cerebral blood flow, as it features high spatial and temporal resolution. However, the quantitative interpretation of the acquired data is not straightforward for the common case of a speckle field formed by both by moving and localized scatterers such as blood cells and bone or tissue. Here we present a novel processing scheme, we call dynamic laser speckle imaging (dLSI), that can be used to correctly extract the temporal correlation parameters from the speckle contrast measured in the presence of a static or slow-evolving background. The static light contribution is derived from the measurements by cross-correlating sequential speckle images. In-vivo speckle imaging experiments performed in the rodent brain demonstrate that dLSI leads to improved results. The cerebral hemodynamic response observed through the thinned and intact skull are more pronounced in the dLSI images as compared to the standard speckle contrast analysis. The proposed method also yields benefits with respect to the quality of the speckle images by suppressing contributions of non-uniformly distributed specular reflections.

Few-cycle laser-driven electron acceleration

We report on an electron accelerator based on few-cycle (8 fs full width at half maximum) laser pulses, with only 40 mJ energy per pulse, which constitutes a previously unexplored parameter range in laser-driven electron acceleration. The produced electron spectra are monoenergetic in the tens-of-MeV range and virtually free of low-energy electrons with thermal spectrum. The electron beam has a typical divergence of 5-10 mrad. The accelerator is routinely operated at 10 Hz and constitutes a promising source for several applications. Scalability of the few-cycle driver in repetition rate and energy implies that the present work also represents a step towards user friendly laser-based accelerators.

Correlation of immunohistopathological expression of somatostatin receptor 2 with standardised uptake values in 68Ga-DOTATOC PET/CT

PURPOSE

In clinical routine somatostatin analogue positron emission tomography/computed tomography (PET/CT) such as (68)Ga-DOTA-Tyr-octreotide (DOTATOC)-PET/CT could substitute conventional (111)In-Octreotide scintigraphy. Immunohistochemistry (IHC) for somatostatin receptor 2 (SSTR2) might be a tool to predict positivity of (68)Ga-DOTATOC in patients where initial staging was not performed, e.g., in incidental findings. We therefore compared a score of SSTR2-IHC with the in vivo standard uptake value (SUV) of preoperative or prebiopsy (68)Ga-DOTATOC PET/CT.

MATERIALS AND METHODS

In 18 patients, (68)Ga-DOTATOC PET/CT scans were quantified with SUV calculations and correlated to a cell membrane-based SSTR2-IHC score (ranging from 0 to 3).

RESULTS

Negative IHC scores were consistent with SUV values below 10. Furthermore, all score 2 and 3 specimens corresponded with high SUV values (above 15).

CONCLUSION

SSTR2-IHC scores correlated well with SUV values and we propose to use SSTR2 immunohistochemistry in patients missing a preoperative PET scan to indicate (68)Ga-DOTATOC-PET/CT as method for restaging and follow-up in individual patients.

Positron detection for the intraoperative localisation of cancer deposits

Purpose

The study investigated the feasibility of a positron-sensitive hand-held detector system for the intraoperative localisation of tumour deposits resulting from intravenous [¹⁸F]FDG administration.

Methods

A total of 17 patients (12 receiving preoperative [¹⁸F]FDG PET imaging) with various histologically proven malignancies were included. Radioactivity from tumours and surrounding normal tissue was measured on average 3 h after administration of 36–110 MBq [¹⁸F]FDG and the tumour-to-background (T/B) ratio was calculated. In addition, phantom studies were performed to evaluate the spatial resolution and sensitivity of the probe.

Results

All known targeted tumour sites were identified by the positron probe. T/B ratios were generally high, with a mean T/B ratio of 6.6, allowing easy identification of most tumour sites. In one case of a hepatic metastasis, the T/B ratio of 1.34 was below expectations, since the preoperative [¹⁸F]FDG PET scan was positive. The probe was instrumental in the localisation of three additional tumour lesions (two lymph nodes, one anastomotic ring) that were not immediately apparent at surgery. Phantom studies revealed that [¹⁸F]FDG-containing gel (simulating tumour tissue), having 10 times more [¹⁸F]FDG than surrounding “normal” background gel, was clearly detectable in quantities as low as 15 mg. As measured in two cases, the absorbed radiation doses ranged from 2.5 to 8.6 μSv/h for the surgical team to 0.8 μSv/h for the aesthetician.

Conclusion

[¹⁸F]FDG-accumulating tumour tissues can be localised with positron probes intraoperatively with a low radiation burden to the patient and medical personnel. The methodology holds promise for further clinical testing.

Transient epileptic opercular syndrome

Ictal transient opercular syndrome is rarely observed in benign epilepsy with centro-temporal spikes in children, and even more rarely in epilepsia partialis continua and symptomatic focal status epilepticus in adults. Here we report the ictal and interictal neuroimaging and electrophysiological findings in an adult female suffering from discontinuous focal status epilepticus presenting as a transient opercular syndrome. This patient was unusual insofar as the discharges were strictly unilateral, i.e., that even with extensive neuroimaging no structural abnormalities could be found.

Use of positron emission tomography for response assessment of lymphoma: consensus of the Imaging Subcommittee of International Harmonization Project in Lymphoma

PURPOSE

To develop guidelines for performing and interpreting positron emission tomography (PET) imaging for treatment assessment in patients with lymphoma both in clinical practice and in clinical trials.

METHODS

An International Harmonization Project (IHP) was convened to discuss standardization of clinical trial parameters in lymphoma. An imaging subcommittee developed consensus recommendations based on published PET literature and the collective expertise of its members in the use of PET in lymphoma. Only recommendations subsequently endorsed by all IHP subcommittees were adopted.

RECOMMENDATIONS

PET after completion of therapy should be performed at least 3 weeks, and preferably at 6 to 8 weeks, after chemotherapy or chemoimmunotherapy, and 8 to 12 weeks after radiation or chemoradiotherapy. Visual assessment alone is adequate for interpreting PET findings as positive or negative when assessing response after completion of therapy. Mediastinal blood pool activity is recommended as the reference background activity to define PET positivity for a residual mass > or = 2 cm in greatest transverse diameter, regardless of its location. A smaller residual mass or a normal sized lymph node (ie, < or = 1 x 1 cm in diameter) should be considered positive if its activity is above that of the surrounding background. Specific criteria for defining PET positivity in the liver, spleen, lung, and bone marrow are also proposed. Use of attenuation-corrected PET is strongly encouraged. Use of PET for treatment monitoring during a course of therapy should only be done in a clinical trial or as part of a prospective registry.

Lateralized and frequency-dependent effects of prefrontal rTMS on regional cerebral blood flow

Repetitive transcranial magnetic stimulation (rTMS) is a means to study the function and connectivity of brain areas. The present study addressed the question of hemispheric asymmetry of frontal regions and aimed to further understand the acute effects of high- and low-frequency rTMS on regional cerebral blood flow (rCBF). Sixteen healthy right-handed men were imaged using H(2)(15)O positron emission tomography (PET) immediately after stimulation. High (10 Hz)- and low (1 Hz)-frequency suprathreshold short-duration rTMS was applied over either the left or right dorsolateral prefrontal cortex (DLPFC). Slow and fast rTMS applied over the left DLPFC significantly increased CBF in the stimulated area. Compared to baseline, slow rTMS induced a significant increase in CBF contralateral to the stimulation site, in the right caudate body and in the anterior cingulum. Furthermore, slow rTMS decreased CBF in the orbitofrontal cortex (OFC, ipsilateral to stimulation side). Fast rTMS applied over the right DLPFC was associated with increased activity at the stimulation site, in the bilateral orbitofrontal cortex and in the left medial thalamus compared to 1-Hz rTMS. These results show that rCBF changes induced by prefrontal rTMS differ upon hemisphere stimulated and vary with stimulation frequency. These differential neurophysiological effects of short-train rTMS with respect to side and frequency suggest hemisphere-dependent functional circuits of frontal cortico-subcortical areas.

H2(15)O or 13NH3 PET and electromagnetic tomography (LORETA) during partial status epilepticus

The authors evaluated the feasibility and source localization utility of H2(15)O or 13NH3 PET and low-resolution electromagnetic tomography (LORETA) in three patients with partial status epilepticus (SE). Results were correlated with findings from intraoperative electrocorticographic recordings and surgical outcomes. PET studies of cerebral blood flow and noninvasive source modeling with LORETA using statistical nonparametric mapping provided useful information for localizing the ictal activity in patients with partial SE.

Immunohistochemical evaluation of endothelial nitric oxide synthase expression in primary breast cancer

To evaluate the clinical potential of endothelial nitric oxide synthase (e-NOS) in human breast cancer, we performed immunohistochemical (IHC) staining of paraffin-embedded primary breast cancer tissue of 163 patients for e-NOS using a monoclonal antibody. A correlation was found between e-NOS expression and both the classic prognostic factors and survival rates. Under half the patients were premenopausal (38.5%), 61.5% being postmenopausal. The median tumour size was 2 cm; in 41.7% of the patients there was involvement of the axillary lymph nodes. Most (84.1%) of the tumours were hormone receptor positive. e-NOS staining was positive in 62%, most of the positive tumours having weak (32.5%) or medium (21.5%) staining for e-NOS. The median follow-up time was 42 months, during which 46 (28%) patients had a local recurrence or metastatic disease. A positive correlation of e-NOS with the hormone receptor status was found (P=0.031). However, no impact on survival rates was observed.

Prospective evaluation of factors influencing success rates of sentinel node biopsy in 814 breast cancer patients

OBJECTIVE

This prospective multicenter study was performed to assess the reliability of sentinel lymph node (SLN) biopsy in breast cancer and to analyze factors potentially influencing success rates.

METHODS

In 21 departments, SLN biopsy and consecutive axillary lymph node dissection were performed in 814 breast cancer patients. The 80 surgeons involved were free in the choice of lymphography technique. The detection rate and the sensitivity, as well as the impact of lymphography technique, patient selection, technical procedure and learning curves, were evaluated.

RESULTS

The blue dye technique was used in 137 patients, radiocolloid in 169 patients, and combined blue dye/radiocolloid in 508 patients. The identification rate for the sentinel node was 83.9% for the entire group and showed a significant dependence on the lymphography technique (blue dye, 71.6%; radiocolloid, 78.8%; combined blue dye and radiocolloid, 89.6%). The overall sensitivity in detecting lymph node metastases was 91.3%. Immunostaining for cytoceratine revealed micrometastases in 19 (5.1%) of 374 patients in whom H/E staining was negative. The combined subdermal/peritumoral injection of the colloid showed a significantly higher identification rate than subdermal or peritumoral injection alone (96.8%, 84.6%, 78.6%; p < 0.001). There was also a significant higher detection rate in cases of SLN biopsy performed prior to lumpectomy, compared to SLN biopsy following lumpectomy (94.7% versus 82.8%; p < 0.001). Furthermore, there was a close correlation between the number of performed examinations and the detection rate.

CONCLUSION

SLN mapping predicts the axillary lymph node status accurately. Learning curves and several technical features influence the detection rate significantly. However, the false negative rate was independent of experience and injection technique.

Pancreatic carcinoma cells induce fibrosis by stimulating proliferation and matrix synthesis of stellate cells

BACKGROUND & AIMS

Tumor desmoplasia is one of the representative histopathologic findings in ductal pancreatic adenocarcinoma. The aims of this study were to examine the cellular and molecular mechanisms of fibrogenesis associated with pancreatic adenocarcinomas.

METHODS

Immunostainings were performed with human pancreatic adenocarcinomas (n = 27) and tumors induced in nude mice (n = 36) by subcutaneously injecting MiaPaCa2, Panc1, and SW850 with and without pancreatic stellate cells. Matrix-producing cells were isolated from pancreatic adenocarcinomas and compared with pancreatic stellate cells isolated from tissue of chronic pancreatitis. Paracrine stimulation of pancreatic stellate cells by carcinoma cells was studied regarding matrix synthesis (collagen and c-fibronectin on protein and messenger RNA level) and cell proliferation (bromodeoxyuridine incorporation).

RESULTS

High numbers of desmin and alpha-smooth muscle actin-positive cells were detected in 26 of 27 pancreatic adenocarcinomas. Intense fibronectin and collagen stainings were associated with these cells. By using cytofilament stainings, gene expression profiling, and morphological examinations, the matrix-producing cells obtained by the outgrowth method from pancreatic adenocarcinomas were identified as pancreatic stellate cells. Supernatants of MiaPaCa2, Panc1, and SW850 cells stimulated proliferation and collagen type I and c-fibronectin synthesis of cultured pancreatic stellate cells. Preincubation of the carcinoma cell supernatants with neutralizing antibodies against fibroblast growth factor 2, transforming growth factor beta 1, and platelet-derived growth factor significantly reduced the stimulatory effects. Subcutaneous injection of carcinoma cells and pancreatic stellate cells induced fast-growing subcutaneous fibrotic tumors in nude mice. Morphometric analysis of carcinoma cells (cytokeratin stainings) showed a high density of carcinoma cells in these tumors.

CONCLUSIONS

Pancreatic stellate cells strongly support tumor growth in the nude mouse model. The increased deposition of connective tissue in pancreatic carcinoma is the result of a paracrine stimulation of pancreatic stellate cells by carcinoma cells.

Attention and interhemispheric transfer: a behavioral and fMRI study

When both detections and responses to visual stimuli are performed within one and the same hemisphere, manual reaction times (RTs) are faster than when the two operations are carried out in different hemispheres. A widely accepted explanation for this difference is that it reflects the time lost in callosal transmission. Interhemispheric transfer time can be estimated by subtracting RTs for uncrossed from RTs for crossed responses (crossed-uncrossed difference, or CUD). In the present study, we wanted to ascertain the role of spatial attention in affecting the CUD and to chart the brain areas whose activity is related to these attentional effects on interhemispheric transfer. To accomplish this, we varied the proportion of crossed and uncrossed trials in different blocks. With this paradigm subjects are likely to focus attention either on the hemifield contralateral to the responding hand (blocks with 80% crossed trials) or on the ipsilateral hemifield (blocks with 80% uncrossed trials). We found an inverse correlation between the proportion of crossed trials in a block and the CUD and this effect can be attributed to spatial attention. As to the imaging results, we found that in the crossed minus uncrossed subtraction, an operation that highlights the neural processes underlying interhemispheric transfer, there was an activation of the genu of the corpus callosum as well as of a series of cortical areas. In a further commonality analysis, we assessed those areas which were activated specifically during focusing of attention onto one hemifield either contra- or ipsilateral to the responding hand. We found an activation of a number of cortical and subcortical areas, notably, parietal area BA 7 and the superior colliculi. We believe that the main thrust of the present study is to have teased apart areas important in interhemispheric transmission from those involved in spatial attention.

Exposure to pulse-modulated radio frequency electromagnetic fields affects regional cerebral blood flow

We investigated the effects of radio frequency electromagnetic fields (RF EMF) similar to those emitted by mobile phones on waking regional cerebral blood flow (rCBF) in 12 healthy young men. Two types of RF EMF exposure were applied: a 'base-station-like' and a 'handset-like' signal. Positron emission tomography scans were taken after 30 min unilateral head exposure to pulse-modulated 900 MHz RF EMF (10 g tissue-averaged spatial peak-specific absorption rate of 1 W/kg for both conditions) and sham control. We observed an increase in relative rCBF in the dorsolateral prefrontal cortex on the side of exposure. The effect depended on the spectral power in the amplitude modulation of the RF carrier such that only 'handset-like' RF EMF exposure with its stronger low-frequency components but not the 'base-station-like' RF EMF exposure affected rCBF. This finding supports our previous observation that pulse modulation of RF EMF is necessary to induce changes in the waking and sleep EEG, and substantiates the notion that pulse modulation is crucial for RF EMF-induced alterations in brain physiology.

Optical imaging of the spatiotemporal dynamics of cerebral blood flow and oxidative metabolism in the rat barrel cortex

Oxidative metabolism and cerebral blood flow (CBF) are two of the most important measures in neuroimaging. However, results from concurrent imaging of the two with high spatial and temporal resolution have never been published. We used flavoprotein autofluorescence (AF) and laser speckle imaging (LSI) in the anaesthetized rat to map oxidative metabolism and CBF in response to single vibrissa stimulation. Autofluorescence responses reflecting oxidative metabolism demonstrated a fast increase with a delay of 0.1 s. The sign-reversed speckle contrast reflecting CBF started to rise with a delay of 0.6 s and reached its maximum 1.4 s after the stimulation offset. The fractional signal changes were 2.0% in AF and 9.7% in LSI. Pixelwise modelling revealed that CBF maps spread over an area up to 2.5-times larger than metabolic maps. The results provide evidence that the increase in cerebral oxidative metabolism in response to sensory stimulation is considerably faster and more localized than the CBF response. This suggests that future developments in functional imaging concentrating on the metabolic response promise an increased spatial resolution.

Civil law problems and morbidity

STUDY OBJECTIVE

In the United Kingdom, recognition of the links between social and health problems has led to government initiatives such as health action zones. The principles of civil law apply to many types of social problem, and the civil justice system provides one means through which they can be tackled. However, little research has been undertaken into the particular links between problems to which civil legal principles and processes can be applied and morbidity. This study examines these links, and the role of legal advice and services in preventing ill health.

DESIGN

This study examined survey respondents' self reports of longstanding illness/disability and experience of 18 problems to which legal principles can be applied.

SETTING

A random national survey conducted across England and Wales.

PARTICIPANTS

5611 adults drawn from 3348 residential households.

MAIN RESULTS

Significant associations were found between illness/disability and 13 of the problem types. Moreover, experience of greater numbers of problems increased the likelihood of reported illness/disability. In attempting to resolve problems respondents' health also frequently suffered.

CONCLUSIONS

This study highlights the contribution that public legal education and legal advice can make to the promotion of public health, and the importance of further integration of health and civil justice initiatives through health action zones, community legal service partnerships, etc, to further this end.