Ischaemic cholangiopathy occurs as a consequence of deficient arterial blood flow to the bile duct wall. Bile duct ischaemia can lead to full-thickness necrosis, bile leakage, biloma formation, and sepsis. It is an important cause of graft failure post-orthotopic liver transplantation. In the native liver, the causes of biliary ischaemia are diverse and include vasculitis or a complication of endovascular procedures. The present review describes the pathology and radiological findings of ischaemic cholangiopathy and outlines the role of interventional radiology in its management. (C) 2019 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Lavelle, L. P.
O'Neill, A. C.
McMahon, C. J.
Cantwell, C. P.
Heffernan, E. J.
Malone, D. E.
Daly, L.
Skehan, S. J.
AIM: To assess if diffusion-weighted imaging (DWI) alone could be used for follow-up of neuroendocrine hepatic metastases. MATERIAL AND METHODS: This was a retrospective study, approved by the institutional review board. Twenty-two patients with neuroendocrine liver metastases who had undergone more than one liver magnetic resonance imaging (MRI) examination, (including DWI and using hepatocyte-specific contrast medium) were evaluated. Up to five metastases were measured at baseline and at each subsequent examination. The reference standard measurement was performed on the hepatocyte phase by one reader. Three independent readers separately measured the same lesions on DWI sequences alone, blinded to other sequences, and recorded the presence of any new lesions. RESULTS: The longest diameters of 317 liver metastases (91 on 22 baseline examinations and a further 226 measurements on follow-up) were measured on the reference standard by one reader and on three b-values by three other readers. The mean difference between DWI measurements and the reference standard measurement was between 0.01-0.08 cm over the nine reader/b-value combinations. Based on the width of the Bland and Altman interval containing approximately 95% of the differences between the reader observation and the mean of reference standard and DWI measurement, the narrowest interval over the nine reader/b-value combinations was -0.6 to +0.7 cm and the widest was -0.9 to 1 cm. In the evaluation of overall response using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria, the weighted kappa statistic was between 0.49 and 0.86, indicating moderate-to-good agreement between the reference standard and DWI. CONCLUSION: The visualisation and measurement of hepatic metastases using DWI alone are within acceptable limits for clinical use, allowing the use of this rapid technique to restage hepatic disease in patients with neuroendocrine metastases. (C) 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Mehta, Yashwant
Dabhade, Vikram V.
Chaudhari, Gajanan P.
The microstructures of Fe–P–C and Fe–P–C–Si–N alloys have been studied to understand the phase distributions and phase transformations during heat treatment. Iron–phosphorus alloys show ghosting features when etched with Nital, since it attacks iron with lower phosphorus content preferentially. The ghostlines mark the boundaries of phosphorus content as it existed at higher temperatures in the austenite–ferrite duplex phase region. Oberhoffer’s reagent reveals the dual-phase microstructure by depositing copper on the low-phosphorus region. The ferrite-to-austenite and reverse transformations were studied and found to occur by nucleation and growth along with diffusion of phosphorus. The morphologies of the phases conform to the Dube system. The phase distribution in dual-phase microstructures was studied using quantitative metallography and compared with the phase fractions obtained from phase diagram calculated using a thermodynamic software. Silicon and nitrogen were added to improve the toughness of the base alloy. Providing homogenization treatment in the upper ferrite region will take less time.
An alkynyl-protected gold nanocluster [Au-40(PhC equivalent to C)(20)(dppm)(4)](SbF6)(4) (dppm =3D bis(diphenylphosphino)methane) (1) has been synthesized. Single-crystal X-ray diffraction reveals that the cluster has a face-centered cubic (FCC) Au-34 kernel that is made up of two Au-20 units via sharing a rectangular face. Two linear PhC equivalent to C-Au-C equivalent to CPh staple motifs are located around the central part of the Au-34 core, and four L-shaped PhC equivalent to C-Au-(PP)-P-boolean AND staple motifs are located at the four corners of the Au-34 core. Cluster 1 and [Au-38(PhC equivalent to C)(20)(PPh3)(4)](CF3SO3)(2) both have the FCC Au-34 core, and it is found that the diphosphine ligands bringing two more Au atoms into the system have significant effects on the optical properties and stability of the clusters. The combination of a diphosphine ligand and an alkynyl ligand is helpful in generating new ligand-protected metal nanoclusters.
Nickel-catalysed P–H/C–CN cross coupling reactions take place efficiently under mild reaction conditions affording the corresponding sp2C–P bonds. This transformation provides a convenient method for the preparation of arylphosphines and arylphosphine oxides from the readily available P–H compounds and arylnitriles.
The first Ni-catalyzed C-O/P-H cross-coupling producing organophosphorus compounds is disclosed. This method features wide generality in regard to both C-O and P-H compounds: for C-O compounds, the readily available alcohol derivatives of aryl, alkenyl, benzyl, and allyl are applicable, and for P-H compounds, both >P-V(O)H compounds (secondary phosphine oxide, H-phosphinate, and H-phosphonate) and hydrogen phosphines (>(PH)-H-III) can be used as the substrates. Thus, a variety of valuable C(sp(2))-P and C(sp(3))-P compounds can be readily obtained in good to excellent yields by this new strategy.