Intraoperative contrast-enhanced sonography of bowel blood flow: preliminary experience

The potential to predict, and therefore avoid, anastomotic failure has eluded generations of colon and rectal surgeons to date. A reliable, reproducible method of assessing bowel blood flow therefore would be of enormous potential clinical relevance. To our knowledge, intraoperative contrast-enhanced sonography of the bowel has not been performed previously. We present our study assessing the feasibility of using contrast-enhanced sonography to study bowel perfusion intraoperatively. We studied 8 patients (4 male and 4 female) with an age range of 52 to 81 years who underwent colorectal surgery (right hemicolectomies, n = 3; Hartmann procedure, n = 1; anterior resections, n = 2; and bowel resections with ileocolic anastomoses, n = 2). A 5-mL bolus of a sulfur hexafluoride contrast agent solution was injected before and after vascular ligation with simultaneous noncompression ultrasound scanning directly over the large bowel. The patients were followed clinically to assess for leaks. Contrast-enhanced sonographic time-intensity curves were generated for the time to peak and maximum amplitude. Moderate interobserver agreement was shown for the time to peak (κ = 0.50) and maximum amplitude (κ = 0.42), and moderate intraobserver agreement was shown for the time to peak (κ= 0.53) and maximum amplitude (κ= 0.53). No significant differences were shown between the time to peak (P = .28) and maximum amplitude (P = .49) for the preligation and postligation scans. To our knowledge, intraoperative contrast-enhanced sonography of the bowel has not been performed previously. We have shown the technique to be feasible with good intraobserver and interobserver agreement. Further work is ongoing to optimize the technique and assess its use in predicting anastomotic breakdown.published_or_final_versio

Combined MR direct thrombus imaging and non-contrast magnetic resonance venography reveal the evolution of deep vein thrombosis: a feasibility study.

OBJECTIVES: Lower limb deep venous thrombosis (DVT) is a common condition with high morbidity and mortality. The aim of the study was to investigate the temporal evolution of the acute thrombus by magnetic resonance imaging (MRI) and its relationship to venous recanalization in patients with recurrent DVTs. METHODS: Thirteen patients with newly diagnosed lower limb DVTs underwent MRI with non-contrast MR venography (NC-MRV) and MR direct thrombus imaging (MR-DTI), an inversion-recovery water-selective fast gradient-echo acquisition. Imaging was performed within 7 days of the acute thrombotic event, then at 3 and 6 months. RESULTS: By 3 months from the thrombotic event a third of the thrombi had resolved and by 6 months about half of the cases had resolved on the basis of vein recanalisation using NC-MRV. On the initial MR-DTI acute thrombus was clearly depicted by hyperintense signal, while the remaining thrombi were predominantly low signal at 3 and 6 months. Some residual thrombi contained small and fragmented persisting hyperintense areas at 3 months, clearing almost completely by 6 months. CONCLUSIONS: Our study suggests that synergistic venous assessment with combined NC-MRV and MR-DTI is able to distinguish acute venous thrombosis from the established (old) or evolving DVT detected by ultrasound. KEY POINTS: • MRI can distinguish between acute and evolving or chronic lower limb DVT • Two advanced MRI techniques can follow the evolution of lower limb DVT • MRI could be used to avoid an incorrect diagnosis of recurrent DVT • MRI could help avoid the risks and complications of lifelong anticoagulation therapy.National Institute for Health Research, Addenbrooke’s Charitable TrustThis is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00330-016-4555-

A disk of dust and molecular gas around a high-mass protostar

The processes leading to the birth of low-mass stars such as our Sun have been well studied, but the formation of high-mass (> 8 x Sun's mass) stars has heretofore remained poorly understood. Recent observational studies suggest that high-mass stars may form in essentially the same way as low-mass stars, namely via an accretion process, instead of via merging of several low-mass (< 8 Msun) stars. However, there is as yet no conclusive evidence. Here, we report the discovery of a flattened disk-like structure observed at submillimeter wavelengths, centered on a massive 15 Msun protostar in the Cepheus-A region. The disk, with a radius of about 330 astronomical units (AU) and a mass of 1 to 8 Msun, is detected in dust continuum as well as in molecular line emission. Its perpendicular orientation to, and spatial coincidence with the central embedded powerful bipolar radio jet, provides the best evidence yet that massive stars form via disk accretion in direct analogy to the formation of low-mass stars

Molecular basis of chemosensitivity of platinum pre-treated ovarian cancer to chemotherapy

Ovarian cancer shows considerable heterogeneity in its sensitivity to chemotherapy both clinically and in vitro. This study tested the hypothesis that the molecular basis of this difference lies within the known resistance mechanisms inherent to these patients' tumours

Elucidating the aetiology of human Campylobacter coli infections

Peer reviewedPublisher PD

Outcome of ATP-based tumor chemosensitivity assay directed chemotherapy in heavily pre-treated recurrent ovarian carcinoma

BACKGROUND: We wished to evaluate the clinical response following ATP-Tumor Chemosensitivity Assay (ATP-TCA) directed salvage chemotherapy in a series of UK patients with advanced ovarian cancer. The results are compared with that of a similar assay used in a different country in terms of evaluability and clinical endpoints. METHODS: From November 1998 to November 2001, 46 patients with pre-treated, advanced ovarian cancer were given a total of 56 courses of chemotherapy based on in-vitro ATP-TCA responses obtained from fresh tumor samples or ascites. Forty-four patients were evaluable for results. Of these, 18 patients had clinically platinum resistant disease (relapse < 6 months after first course of chemotherapy). There was evidence of cisplatin resistance in 31 patients from their first ATP-TCA. Response to treatment was assessed by radiology, clinical assessment and tumor marker level (CA 125). RESULTS: The overall response rate was 59% (33/56) per course of chemotherapy, including 12 complete responses, 21 partial responses, 6 with stable disease, and 15 with progressive disease. Two patients were not evaluable for response having received just one cycle of chemotherapy: if these were excluded the response rate is 61%. Fifteen patients are still alive. Median progression free survival (PFS) was 6.6 months per course of chemotherapy; median overall survival (OAS) for each patient following the start of TCA-directed therapy was 10.4 months (95% confidence interval 7.9-12.8 months). CONCLUSION: The results show similar response rates to previous studies using ATP-TCA directed therapy in recurrent ovarian cancer. The assay shows high evaluability and this study adds weight to the reproducibility of results from different centre

High Energy Neutrino Astronomy: Towards Kilometer-Scale Detectors

Of all high-energy particles, only neutrinos can directly convey astronomical information from the edge of the universe---and from deep inside the most cataclysmic high-energy processes. Copiously produced in high-energy collisions, travelling at the velocity of light, and not deflected by magnetic fields, neutrinos meet the basic requirements for astronomy. Their unique advantage arises from a fundamental property: they are affected only by the weakest of nature's forces (but for gravity) and are therefore essentially unabsorbed as they travel cosmological distances between their origin and us. Many of the outstanding mysteries of astrophysics may be hidden from our sight at all wavelengths of the electromagnetic spectrum because of absorption by matter and radiation between us and the source. For example, the hot dense regions that form the central engines of stars and galaxies are opaque to photons. In other cases, such as supernova remnants, gamma ray bursters, and active galaxies, all of which may involve compact objects or black holes at their cores, the precise origin of the high-energy photons emerging from their surface regions is uncertain. Therefore, data obtained through a variety of observational windows---and especially through direct observations with neutrinos---may be of cardinal importance. In this talk, the scientific goals of high energy neutrino astronomy and the technical aspects of water and ice Cherenkov detectors are examined, and future experimental possibilities, including a kilometer-square deep ice neutrino telescope, are explored.Comment: 13 pages, Latex, 6 postscript figures, uses aipproc.sty and epsf.sty. Talk presented at the International Symposium on High Energy Gamma Ray Astronomy, Heidelberg, June 200

ALMA observations of the Extended Green Object G19.01−0.03 – I. A Keplerian disc in a massive protostellar system

Using the Atacama Large Millimetre/submillimeter Array (ALMA) and the Karl G. Jansky Very Large Array (VLA), we observed the Extended Green Object (EGO) G19.01-0.03 with sub-arcsec resolution from 1.05 mm to 5.01 cm wavelengths. Our 0.4 arcsec 1600 au angular resolution ALMA observations reveal a velocity gradient across the millimetre core MM1, oriented perpendicular to the previously known bipolar molecular outflow, which is consistently traced by 20 lines of 8 molecular species with a range of excitation temperatures, including complex organic molecules (COMs). Kinematic modelling shows the data are well described by models that include a disc in Keplerian rotation and infall, with an enclosed mass of 40-70 M (within a 2000 au outer radius) for a disc inclination angle of i = 40, of which 5.4-7.2 M is attributed to the disc. Our new VLA observations show that the 6.7 GHz Class II methanol masers associated with MM1 fo a partial ellipse, consistent with an inclined ring, with a velocity gradient consistent with that of the theal gas. The disc-to-star mass ratio suggests the disc is likely to be unstable and may be fragmenting into as-yet-undetected low-mass stellar companions. Modelling the centimetre-millimetre spectral energy distribution of MM1 shows the ALMA 1.05 mm continuum emission is dominated by dust, whilst a free-free component, interpreted as a hypercompact H ii region, is required to explain the VLA 5 cm emission. The high enclosed mass derived for a source with a moderate bolometric luminosity (104L) suggests that the MM1 disc may feed an unresolved high-mass binary system

Filamentary mass accretion towards the high-mass protobinary system G11.92-0.61 MM2

We present deep, sub-arcsecond (2000 au) resolution ALMA 0.82-mm observations of the former high-mass prestellar core candidate G11.92-0.61 MM2, recently shown to be an 500 au-separation protobinary. Our observations show that G11.92-0.61 MM2, located in the G11.92-0.61 protocluster, lies on a filamentary structure traced by 0.82-mm continuum and NH(4-3) emission. The NH(4-3) spectra are multipeaked, indicative of multiple velocity components along the line of sight. To analyse the gas kinematics, we performed pixel-by-pixel Gaussian decomposition of the NH spectra using scousepy and hierarchical clustering of the extracted velocity components using acorns. Seventy velocity- and position-coherent clusters (called 'trees') are identified in the NH-emitting gas, with the eight largest trees accounting for 60 per cent of the fitted velocity components. The primary tree, with 20 per cent of the fitted velocity components, displays a roughly north-south velocity gradient along the filamentary structure traced by the 0.82-mm continuum. Analysing an 0.17 pc-long substructure, we interpret its velocity gradient of 10.5 km s pc as tracing filamentary accretion towards MM2 and estimate a mass inflow rate of to 1.2 M yr. Based on the recent detection of a bipolar molecular outflow associated with MM2, accretion on to the protobinary is ongoing, likely fed by the larger scale filamentary accretion flows. If 50 per cent of the filamentary inflow reaches the protostars, each member of the protobinary would attain a mass of 8 M within yr, comparable to the combined time-scale of the 70-μm- and mid-infrared-weak phases derived for ATLASGAL-TOP100 massive clumps using chemical clocks

Ultrasound imaging of the carpal tunnel during median nerve compression

Median nerve (MN) compression is a recognized component of carpal tunnel syndrome (CTS). In order to document compressive changes in the MN during hand activity, the carpal tunnel was imaged with neuromuscular ultrasound (NMUS). Ten patients with CTS and five normal controls underwent NMUS of the MN at rest and during dynamic stress testing (DST). DST maneuvers involve sustained isometric flexion of the distal phalanges of the first three digits. During DST in the CTS patients, NMUS demonstrated MN compression between the contracting thenar muscles ventrally and the taut flexor tendons dorsally. The mean MN diameter decreased nearly 40%, with focal narrowing in the mid-distal carpal canal. Normal controls demonstrated no MN compression and a tendency towards MN enlargement, with an average diameter increase of 17%. Observing the pathologic mechanism of MN injury during common prehensile hand movements could help better understand how to treat and prevent CTS