Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography

The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.     

Intrahepatic bile duct and portal vein anatomy revisited

Seventeen normal cadaver livers were studied to assess the anatomic relationship of bile ducts to portal veins. The common bile duct, main portal vein, and hepatic artery were cannulated and injected with air, dilute contrast medium, and mineral oil, respectively. The livers were placed in anatomic position and examined with computed tomography. In the lateral segment of the left hepatic lobe, the bile ducts were anterior to the portal vein in seven cases, posterior in seven, and tortuous (ie, both anterior and posterior) in three. In the medial segment of the left lobe, the bile ducts were anterior in four cases, posterior in four, tortuous in three, and not seen in six. In the right lobe, the bile ducts were anterior in nine cases, posterior in five, tortuous in one, and not seen in two. In the porta hepatis, the bile ducts were anterior in ten cases, posterior in one, tortuous in five, and not seen in one. Histologic findings confirmed the anterior and posterior location of the bile ducts relative to the portal veins. These findings contradict the commonly held view of intrahepatic bile ducts being anterior to the portal vein and are clinically significant for techniques such as bile duct drainage.     

Indocyanine green fluorescence and three-dimensional imaging of right gastroepiploic artery in gastric tube cancer

A 79-year-old male was admitted to our hospital for the treatment of cancer of the gastric tube.Gastrointestinal examination revealed a T1 b Union for International Cancer Control(UICC) tumor at the pyloric region of the gastric tube.Laparotomy did not reveal infiltration intothe serosa,peritoneal dissemination,regional lymph node swelling,or distant metastasis.We performed a distal gastrectomy preserving the right gastroepiploic artery by referencing the preoperative three-dimensional computed tomoangiography.We also evaluated the blood flow of the right gastroepiploic artery and in the proximal gastric tube by using indocyanine green fluorescence imaging intra-operatively and then followed with a gastrojejunal anastomosis with Roux-en-Y reconstruction.The definitive diagnosis was moderately differentiated adenocarcinoma of the gastric tube,pT 1bN 0M0,pS tage IA(UICC).His postoperative course was uneventful.Three-dimensional computed tomographic imaging is effective for assessing the course of blood vessels and the relationship with the surrounding structures.Intraoperative evaluation of blood flow of the right gastroepiploic artery and of the gastric tube in the anastomotic portion is very valuable information and could contribute to a safe gastrointestinal reconstruction.     

Features of myocardial injury in severe organophosphate poisoning

Background. In organophosphate (OP) poisoning cardiac complications may occur. However, the current body of knowledge largely consists of limited studies, and case reports are mainly on electrocardiogram (ECG) abnormalities. As definite myocardial injury is difficult to assess through ECG, we investigated the prevalence of myocardial injury through cardiac biochemical markers such as troponin I (TnI) in severe OP poisoning. Methods. We conducted a retrospective review of 99 consecutive OP insecticide poisoning cases that were diagnosed and treated at the emergency department of the Wonju Severance Christian Hospital between March 2008 and December 2013. Results. Based on Namba classification for OP poisoning, there were no patients with mild toxicity, 9 patients (9.1%) with moderate toxicity and 90 patients (90.9%) with severe toxicity. On ECG, normal sinus rhythm was most common, and ST depression and elevation were seen in 11 patients (11.1%). Elevation of TnI within 48 h was seen in 34 patients (34.3%). The median peak level and peak time of TnI were 0.305 (IQR, 0.078–2.335) ng/mL and 15 (IQR 6.9–34.4) hours, respectively. There were differences between patients with normal TnI and elevated TnI in terms of age (yrs), number of patients who were exposed to OP via the oral route, and initial Glasgow Coma Scale (GCS; 58 ± 17 vs. 66 ± 16, p = 0.015, 56 [87.5%] vs. 33 [97.1%], p = 0.048 and 12.0 [IQR, 8.0–15.0] vs. 9.0 [IQR, 5.8–12.0], p = 0.019). Conclusions. OP can cause direct myocardial injury during the acute early phase in severe OP poisoning. Monitoring of TnI may be needed in severe OP poisoning.     

Impairment of secondary peristalsis in Barrett’s esophagus by transnasal endoscopy-based testing

AIM:To investigate dysfunctions in esophageal peristalsis and sensation in patients with Barrett’s esophagus following acid infusion using endoscopy-based testing.METHODS:First,physiological saline was infused into the esophagus of five healthy subjects,at a rate of 10 mL/min for 10 min,followed by infusion of HCl.Esophageal contractions were analyzed to determine whether the contractions observed by endoscopy and ultrasonography corresponded to the esophageal peristaltic waves diagnosed by manometry.Next,using nasal endoscopy,esophageal sensations and contractions were investigated in patients with,as well as controls without,Barrett’s esophagus using the same infusion protocol.RESULTS:All except one of the propulsive contractions identified endoscopically were recorded as secondary peristaltic waves by manometry.Patients with long segment Barrett’s esophagus(LSBE)tended to have a shorter lag time than the control group,although the difference did not reach statistical significance(88±54s vs 162±150 s respectively,P=0.14).Furthermore,patients with LSBE had significantly fewer secondary contractions following the infusion of both saline and HCl than did either the control group or patients with short segment Barrett’s esophagus(4.1±1.2 vs 8.0±2.8,P<0.001 and 7.3±3.2,P<0.01,respectively,following saline infusion;5.3±1.2vs 8.4±2.4 and 8.1±2.9 respectively,P<0.01 for both,following infusion of HCl).CONCLUSION:Using nasal endoscopy and a simple acid-perfusion study,we were able to demonstrate disorders in secondary peristalsis in patients with LSBE.     

Differential effect of agonistic anti-CD40 on human mature and immature dendritic cells: the Janus face of anti-CD40

Agonistic monoclonal antibodies to CD40 (CD40 mAbs) have a puzzling dual therapeutic effect in experimental animal models. CD40 mAbs induce tumor regression by potentiating antitumoral T-cell responses, yet they also have immunosuppressive activity in chronic autoimmune inflammatory processes. CD40 mAbs are thought to act on antigen presentation by dendritic cells (DCs) to T cells. DCs can be distinguished as either immature or mature by their phenotype and their ability to generate an effective T-cell response. Here we found that, on human cells, although anti-CD40 led immature DCs to mature and became immunogenic, it also reduced the capacity of lipopolysaccharide (LPS) and tumor necrosis factor alpha (TNF-alpha)-matured DCs to generate a specific CD4 T-cell response. This inhibitory effect was related to rapid and selective apoptosis of mature DCs. Anti-CD40-mediated apoptosis was due to an indirect mechanism involving cooperation with the death domain-associated receptor Fas, leading to activation of Fas-associated death domain protein (FADD) and caspase-8. On human cells, CD40 activation by such agonists could, therefore, trigger immune responses to antigens presented by immature DCs, which are otherwise nonimmunogenic, by inducing maturation. On the other hand, anti-CD40 mAbs, by rapidly inducing apoptosis, may reduce the capacity of inflammatory signal-matured immunogenic DCs to generate an effective T-cell response. These results call for caution in CD40 mAb-based immunotherapy strategies.     

Plastid genomes of the Rhodophyta and Chromophyta constitute a distinct lineage which differs from that of the Chlorophyta and have a composite phylogenetic origin,perhaps like that of the Euglenophyta

Summary A phylogenetic tree has been constructed from comparisons of entire 16S rRNA gene sequences from different prokaryotes and from several algal plastids. According to this study, and to previous work on the ribulose-1,5-bisphosphate carboxylase oxygenase (Rubisco) large and small subunit genes, we postulate that: (1) rhodophyte and chromophyte plastid genomes have a common, composite phylogenetic origin which implies at least two different ancestors, a cyanobacterial and a -proteobacterial ancestor; (2) chlorophyte (green algae and land plants) plastids have a cyanobacterial ancestor which probably differs from that of rhodophyte and chromophyte plastids, and in any case constitute a different lineage; (3) euglenophyte plastid genomes also seem to have a composite phylogenetic origin which involves two different lineages.