What the radiologist should know about postoperative MDCT evaluation of a patient treated with cytoreductive surgery with or without hyperthermic intraperitoneal chemotherapy.

Cytoreductive surgery (CRS), often associated with hyperthermic intraperitoneal chemotherapy (HIPEC), is now a well-recognised treatment for most peritoneal malignancies in selected patients. As imaging is frequently performed postoperatively, radiologists are increasingly confronted with postoperative multidetector-row computed tomography (MDCT) examinations in these cases. In this article, after briefly describing the procedures that are currently being performed for the treatment of peritoneal metastases, the normal postoperative MDCT changes that may be encountered after these procedures are described. We then highlight complications that may arise after CRS, depending on the surgery performed, and those related to HIPEC, and illustrate their MDCT features.

Is there a benefit of mechanical thrombectomy in patients with large stroke (DWI-ASPECTS ≤ 5)?

BACKGROUND AND PURPOSE: Whether to withhold mechanical thrombectomy when the diffusion-weighted imaging (DWI) lesion exceeds a given volume is undetermined. Our aim was to identify markers that will help to select patients with large DWI lesions [DWI-Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS) ≤ 5] that may benefit from thrombectomy. METHODS: From May 2010 to November 2016, 82 acute ischaemic stroke patients with DWI-ASPECTS ≤5 (43 men, 64.6 ± 14.4 years, National Institutes of Health Stroke Scale 18.4 ± 5.4) treated with state-of-the-art mechanical thrombectomy were studied. Thrombectomy alone was performed in 28 (34%) and bridging therapy in 54 (66%) patients. Recanalization was defined as a thrombolysis in cerebral infarction score 2B-3 and significant hemorrhagic transformation as parenchymal haematoma type 2 (European Cooperative Acute Stroke Study 3 classification). Pretreatment variables were compared between patients with a good (modified Rankin Scale 0-2) and a poor (modified Rankin Scale 3-6) neurological outcome at 3 months. RESULTS: Overall, 28 patients (34%) achieved good neurological outcome at 3 months. Recanalizers were significantly more likely to achieve good outcome (61% vs. 7.3%, P < 0.0001), had lower mortality (24% vs. 49%, P = 0.03) and similar rates of parenchymal haematoma type 2 (9.8% vs. 7.3%, P = 1) compared to non-recanalizers. Regression modelling identified DWI-ASPECTS >2 [odds ratio (OR) 6.93; 95% confidence interval (CI) 1.05-45.76, P = 0.04), glycaemia ≤6.8 mmol/l (OR 4.05; 95% CI 1.09-15.0, P = 0.03) and thrombolysis (OR 3.67; 95% CI 1.04-12.9, P = 0.04) as independent predictors of good neurological outcome. CONCLUSIONS: In patients with DWI-ASPECTS ≤5, two-thirds of patients experienced good neurological outcome when recanalized by state-of-the-art thrombectomy, whilst only one in 14 non-recanalizers achieved similar outcomes. Pretreatment markers of good neurological outcomes were DWI-ASPECTS >2, intravenous thrombolysis and glycaemia ≤6.8 mmol/l.

Validation and evaluation of a novel time-resolved laser-induced fluorescence technique.

We present a novel technique to measure time-resolved laser-induced fluorescence signals in plasma sources that have a relatively constant Fourier spectrum of oscillations in steady-state operation, but are not periodically pulsed, e.g., Hall thrusters. The technique uses laser modulation of the order of MHz and recovers signal via a combination of band-pass filtering, phase-sensitive detection, and averaging over estimated transfer functions calculated for many different cycles of the oscillation. Periodic discharge current oscillations were imposed on a hollow cathode. Measurements were validated by comparison with independent measurements from a lock-in amplifier and by comparing the results of the transfer function average to an independent analysis technique triggering averaging over many oscillation cycles in the time domain. The performance of the new technique is analyzed and compared to prior techniques, and it is shown that this new technique has a niche in measurements where the analog photomultiplier signal has a nonwhite noise spectral density and cycles of oscillation are not sufficiently repeatable to allow for reliable triggering or a meaningful average waveform in the time domain.

The adenovirus E4-ORF4 splicing enhancer protein interacts with a subset of phosphorylated SR proteins.

SR proteins purified from uninfected HeLa cells inhibit adenovirus IIIa pre-mRNA splicing by binding to the intronic IIIa repressor element (3RE). In contrast, SR proteins purified from late adenovirus-infected cells are functionally inactivated as splicing repressor proteins by a virus-induced dephosphorylation. We have shown that the adenovirus E4-ORF4 protein, which binds the cellular protein phos phatase 2A (PP2A) and activates IIIa splicing in vitro and in vivo, induces SR protein dephosphorylation. Here we show that E4-ORF4 interacts with only a subset of SR proteins present in HeLa cells. Thus, E4-ORF4 interacts efficiently with SF2/ASF and SRp30c, but not with other SR proteins. Interestingly, E4-ORF4 interacts with SF2/ASF through the latter's RNA recognition motifs. Furthermore, E4-ORF4 interacts preferentially with the hyperphosphorylated form of SR proteins found in uninfected HeLa cells. E4-ORF4 mutant proteins that fail to bind strongly to PP2A or SF2/ASF do not relieve the repressive effect of HeLa SR proteins on IIIa pre-mRNA splicing in transient transfection experiments, suggesting that an interaction between all three proteins is required for E4-ORF4-induced SR protein dephosphorylation.