Wide field of view CT: clinical impact in medical imaging

Although Computer Tomography (CT) has been widely used for medical imaging over the previous thirty years, recent advances in the superior to inferior coverage of multidetector systems have contributed to the introduction of wide field of view CT units. The immediate clinical benefit of wide field of view is the ability to apply the scan to a region of interest with a view to avoiding table motion, should the coverage with one gantry rotation be adequate. We considered investigating wide field of view CT and determining other potential benefits, which may not be readily visible. Areas of interest include myocardial tissue and the ability to assess density of the entire heart at the same point in time, brain perfusion and joint motion assessment. We determined that certain absolute parameters for imaging the heart with regard to temporal resolution no longer need to be met, and establishment of baseline myocardial density values were of importance considering the significant impact of volumetric imaging in the setting of myocardial perfusion and both rest and stress assessment. Baseline measurements for previously poorly assessed and poorly understood joints were determined, including the acromioclavicular and wrist joints. A significant benefit of investigating abnormal wrist motion was the discovery of a clinical entity which has previously not been appreciated, that of trigger lunate syndrome. We propose that wide field of view CT, and in particular 4D CT, have a significant benefit in clinical imaging, and that 4D CT may be considered a new imaging technique allowing us to visualize and examine motion and perfusion disorders which have previously either been not possible or significantly limited

Wide field of view CT: clinical impact in medical imaging

Although Computer Tomography (CT) has been widely used for medical imaging over the previous thirty years, recent advances in the superior to inferior coverage of multidetector systems have contributed to the introduction of wide field of view CT units. The immediate clinical benefit of wide field of view is the ability to apply the scan to a region of interest with a view to avoiding table motion, should the coverage with one gantry rotation be adequate. We considered investigating wide field of view CT and determining other potential benefits, which may not be readily visible. Areas of interest include myocardial tissue and the ability to assess density of the entire heart at the same point in time, brain perfusion and joint motion assessment. We determined that certain absolute parameters for imaging the heart with regard to temporal resolution no longer need to be met, and establishment of baseline myocardial density values were of importance considering the significant impact of volumetric imaging in the setting of myocardial perfusion and both rest and stress assessment. Baseline measurements for previously poorly assessed and poorly understood joints were determined, including the acromioclavicular and wrist joints. A significant benefit of investigating abnormal wrist motion was the discovery of a clinical entity which has previously not been appreciated, that of trigger lunate syndrome. We propose that wide field of view CT, and in particular 4D CT, have a significant benefit in clinical imaging, and that 4D CT may be considered a new imaging technique allowing us to visualize and examine motion and perfusion disorders which have previously either been not possible or significantly limited

[2Fe-2S]-Ferredoxin Binds Directly to Cysteine Desulfurase and Supplies an Electron for Iron–Sulfur Cluster Assembly but Is Displaced by the Scaffold Protein or Bacterial Frataxin

Escherichia coli [2Fe-2S]-ferredoxin (Fdx) is encoded by the <i>isc</i> operon along with other proteins involved in the ‘house-keeping’ mechanism of iron–sulfur cluster biogenesis. Although it has been proposed that Fdx supplies electrons to reduce sulfane sulfur (S⁰) produced by the cysteine desulfurase (IscS) to sulfide (S^2–) as required for the assembly of Fe–S clusters on the scaffold protein (IscU), direct experimental evidence for the role of Fdx has been lacking. Here, we show that Fdx (in either oxidation state) interacts directly with IscS. The interaction face on Fdx was found to include residues close to its Fe–S cluster. In addition, C328 of IscS, the residue known to pick up sulfur from the active site of IscS and deliver it to the Cys residues of IscU, formed a disulfide bridge with Fdx in the presence of an oxidizing agent. Electrons from reduced Fdx were transferred to IscS only in the presence of l-cysteine, but not to the C328S variant. We found that Fdx, IscU, and CyaY (the bacterial frataxin) compete for overlapping binding sites on IscS. This mutual exclusion explains the mechanism by which CyaY inhibits Fe–S cluster biogenesis. These results (1) show that reduced Fdx supplies one electron to the IscS complex as S⁰ is produced by the enzymatic conversion of Cys to Ala and (2) explain the role of Fdx as a member of the <i>isc</i> operon

Middle colic vein draining to splenic vein: a rare anatomic variation encountered during a right hemicolectomy

Right or subtotal colectomy either open or laparoscopic may be a challenging operation owing to technical difficulties. One of these, is to identify a safe and adequate dissection plane, ligating and dissecting lymph nodes around middle colic vessels. The purpose of this study was to depict a rare anatomic variation of middle colic vein (MCV) draining to splenic vein. We report the case of a 55-year-old male patient, who was subjected to a right hemicolectomy for an adenocarcinoma in the ascending colon. During dissecting the transverse mesocolon from the greater omentum, for complete mesocolic excision (CME), we encountered that the MCV drained in the splenic vein. With respect of this rare anatomic variability, CME was completed without hemorrhage. Our aim is to depict that deep knowledge of MCV anatomy and its variations is of paramount importance to achieve CME and to avoid dangerous or massive bleeding