Immunogenicity of recombinant Plasmodium falciparum SERA proteins in rodents

We have expressed defined regions of the serine-repeat antigen (SERA) of the Honduras-1 strain of Plasmodium falciparum in the yeast Saccharomyces cerevisiae. Amino-terminal domains of the natural SERA protein have been shown previously to be targets for parasite-inhibitory murine monoclonal antibodies. Two recombinant SERA antigens were selected for purification and immunological analysis. The first (SERA 1), corresponding to amino acids 24-285 of the natural SERA precursor, was expressed by the ubiquitin fusion method. This allowed for in vivo cleavage by endogenous yeast ubiquitin hydrolase, and subsequent isolation of the mature polypeptide. The second, larger protein (SERA N), encompassing amino acids 24-506, was expressed at only low levels using this system, but could be isolated in high yields when fused to human gamma-interferon (gamma-IFN). Each purified protein was used to immunize mice with either Freund's adjuvant or a muramyl tripeptide adjuvant that has been used in humans. Sera from immunized mice were shown to be capable of in vitro inhibition of invasion of erythrocytes by the Honduras-1 strain of P. falciparum. The results suggest that a recombinant SERA antigen may be an effective component of a candidate malaria vaccine.     

Test-bolus injection for optimization of arterial phase imaging during contrast-enhanced hepatic MR imaging

Contrast enhancement during the dynamic MR imaging is important for the detection and characterization of focal liver lesions. The purpose of this study was to determine whether or not a timing examination with a injection of a 1.0-mL bolus of gadopentetate dimeglumine into the antecubital vein followed by rapid dynamic scanning and measurement of signal intensity of the aorta could help to obtain proper arterial-dominant phase images for the characterization of focal hepatic lesions during subsequent multiphase dynamic MR imaging. The imaging delay to acquisition of the first gadolinium-enhanced image for multiphase dynamic MR imaging was set to equal the time to peak aortic enhancement during the test examination. The first contrast-enhanced images of 80 patients with 160 focal liver lesions (hepatocellular carcinoma, n = 79; cavernous hemangioma, n = 51; metastatic tumor, n = 30) were then retrospectively reviewed. Peak aortic enhancement occurred between 10 and 28 seconds (mean, 16.5 seconds +/- 3.1) after starting the infusion of contrast material in 80 patients during the test-examination. Depending on the findings of intrahepatic vascular enhancement on the full-scale dynamic images, hepatic arterial phase (n = 11, 14%) or sinusoid phase (n = 65, 81%) imaging was obtained during the first gadolinium-enhanced acquisition in 76 (95%) of 80 patients. Three different lesions were well characterized and easily distinguished from each other (p < .0001) on the first-phase images depending on their enhancement pattern. In the majority of patients, timing examination with test-bolus injection was helpful in obtaining qualified images for the characterization of various focal lesions.     

CM1 ligation initiates apoptosis in a caspase 8-dependent manner in Ramos cells and in a mitochondria-controlled manner in Raji cells

Burkitt lymphoma (BL) is a tumor with the characteristics of germinal center B cells. We previously reported that the CM1 (centrocyte/-blast marker 1) molecule is expressed only in germinal center B cells, specifically, in a subpopulation of centroblasts and centrocytes. In the present study, we investigated the apoptosis induced by anti-CM1 in the Ramos and Raji human BL cell lines. The Ramos is protected from apoptosis by the crosslinking of sIgM and the calcium ionophore by the ligation of CD40 with anti-CD40 monoclonal antibodies (mAb) or soluble CD40 ligand (sCD40L). In this investigation on the effect of CM1 on apoptosis in BL cell lines, we found that cellular signaling by CM1 induces apoptosis and decreases cell viability, in BL cell lines cultured for 24 hours with protein-G agarose beads conjugated anti-CM1 mAb. Stimulation by CD40 ligated with sCD40L protected Raji cells from CM1-induced apoptosis, but did not protect Ramos cells. Furthermore, after anti-CM1 mAb stimulation, CD95 expression was upregulated and CD40 expression was unaltered or slightly decreased in Ramos cells, whereas CD95 was downregulated and CD40 was slightly upregulated in Raji cells. The engagement of CD40 by sCD40L enhanced CD95 expression, but the level of CM1 expression was unchanged in Ramos. However, sCD40L downregulated both CD95 and CM1 expression in Raji. In addition, the caspase-8 specific inhibitor blocked CM1-induced apoptosis in Ramos cells, but not in Raji cells. Increased mitochondrial membrane permeabilization was observed only in Raji cells. Moreover, the effector caspase inhibitor, z-DEVD, blocked CM1-mediated apoptosis in both cell lines. We found that CM1-induced apoptosis is achieved via different initiation pathways, which are cell-type dependent.     

Anti-TWEAK monoclonal antibodies reduce immune cell infiltration in the central nervous system and severity of experimental autoimmune encephalomyelitis

TWEAK is a member of the TNF family, constitutively expressed in the central nervous system (CNS), with pro-inflammatory, proliferative or apoptotic effects depending upon cell types. Its receptor, Fn14, is expressed in CNS by endothelial cells, reactive astrocytes and neurons. We showed that TWEAK and Fn14 mRNA expression increased in spinal cord during experimental autoimmune encephalomyelitis (EAE). We investigated the role of TWEAK during EAE using neutralizing anti-TWEAK antibody in myelin oligodendrocyte glycoprotein (MOG) induced EAE in C57BL/6 mice. We observed a reduction of disease severity and leukocyte infiltration when mice were treated after the priming phase.     

The "High-Riding" superior pericardial recess: CT findings

OBJECTIVE. We recently observed patients in whom the superior pericardial recess extended cephalad ("high-riding") into the right paratracheal region. In these patients, differentiation from mediastinal lymphadenopathy or mass was difficult. The purpose of this study was to assess the prevalence and CT features of the high-riding superior pericardial recess. CONCLUSION. Narrow-collimation CT with multiplanar reformations was useful for confidently diagnosing a high-riding superior pericardial recess and for distinguishing it from pathologic lesions.     

High residual platelet reactivity (HRPR) for adenosine diphosphate (ADP) stimuli is a determinant factor for long-term outcomes in acute ischemic stroke with anti-platelet agents: The meaning of HRPR after ADP might be more prominent in large atherosclerotic infarction than other subtypes of AIS

High residual platelet activation (HRPA) after ADP stimuli has associated with recurrent vascular events in acute atherothrombosis with the use of antiplatelet agents (APAs). However, there has been little evidence supporting this association in acute ischemic stroke (AIS). In this study, we evaluated the influences of HRPR after ADP stimuli on the 1-year incidence of recurrent cardiovascular events and mortality in AIS with APAs. We conducted an observational, referral center cohort study on 968 AIS patients with APAs from January 2010 to December 2013 who were evaluated using optical platelet aggregometry (OPA). All patients received the dual APA combination of aspirin and clopidogrel or aspirin alone. We evaluated their platelet function 5 days after hospital admission using OPA. HRPR after ADP stimuli was defined as platelet aggregation of 70 % or greater according to OPA after 10 µM ADP stimuli. The primary endpoint was a composite of all causes of death, myocardial infarction, and stroke at the 1-year follow-up. The secondary endpoints were each component of the primary endpoint. The event rate of primary endpoint was 11.3 % (109/968). Its rate was significantly higher in the patients with HRPR (16.7 %) than in those without (9.7 %). HPRP was independently associated with the primary endpoint (OR = 1.97, CI 1.22–3.18, p < 0.01). According to the AIS subtype, the presence of HRPR was independently significant for the occurrence of the primary endpoint in the large artery atherosclerosis (LAA) subtype only (OR = 2.26, CI 1.15–4.45, p = 0.02). In this study, the presence of HRPR after ADP stimuli is associated with a poor long-term outcome after acute ischemic stroke. In particular, the influence of this factor might be more prominent in LAA compared with other types of AIS.     

Localized esophageal ulcerations after CyberKnife treatment for metastatic hepatic tumor of colon cancer.

CyberKnife is an image-guided robotic system designed for stereotactic radiosurgery. It uses the combination of robotics and image guidance to deliver concentrated and accurate beams of radiation to intracranial and extracranial targets. Although the frameless nature of the CyberKnife allows tumors in the chest and abdomen to be treated as well, complications associated with CyberKnife treatment have not been established yet due to its short clinical experience. We describe a case of localized esophageal ulcerations after CyberKnife treatment for metastatic hepatic tumor of colon cancer.     

Protective immunity induced in Aotus monkeys by recombinant SERA proteins of Plasmodium falciparum.

We describe the vaccination of Panamanian monkeys (Aotus sp.) with two recombinant blood stage antigens that each contain a portion of the N-terminal region of the SERA (serine repeat antigen) protein of the malaria parasite Plasmodium falciparum. We immunized with either a 262-amino-acid SERA fragment (SERA I) that contains amino acids 24 to 285 of the 989-amino-acid protein or a 483-amino-acid SERA fragment (SERA N) that contains amino acids 24 to 506 as part of a fusion protein with human gamma interferon. The recombinant proteins were shown to stimulate protective immunity when administered with complete and incomplete Freund adjuvant. Four of six immunized monkeys challenged by intravenous inoculation with blood stage P. falciparum developed parasitemias that were reduced by at least 1,000-fold. Two of six immunized monkeys developed parasitemias which were comparable to the lowest parasitemia in one of four controls and were 50- to 1,000-fold lower than in the other three controls.     

Standardization of flap design for oropharyngeal reconstruction after cancer ablation surgery

A variety of residual defects containing many sulci and fossae in the oropharyngeal cavity make it extremely difficult to achieve an adequate flap design as well as the functional reconstruction of the complex defects after ablation surgery for oropharyngeal tumors. This study attempted to standardize flap design for the different types of defects in order to produce a better functional reconstruction of intra-oral defects. The oropharyngeal defects were classified into 6 Zones. When the defect involves only the mouth floor, it was classified as Zone 1. A hemi tongue was classified as Zone 2. A defect involving the mouth floor and a part of the tongue was classified as Zone 3. A defect involving the mouth floor, a part of the tongue and the tonsil was classified as Zone 4. A defect involving the mouth floor, a part of the tongue, tonsil and soft palate was classified as Zone 5. A defect involving the pharyngeal wall was classified as Zone 6. The following four types of forearm free flap designs were applied to each defective Zone accordingly: Type I flap design - an unilobed design for reconstructing Zone 1, 2 and 6 defects, Type II design - bilobed design for reconstructing Zone 3 defects, Type III design - trilobed design for reconstructing Zone 4 defects and Type IV design for reconstructing Zone 5 defects. During 1999 to 2002, 91 patients with oropharyngeal defects underwent a reconstruction using these standardized forearm free flap designs. The Type I design was used in 41 cases, the Type II design in 18 cases, the Type III design in 10 cases and the Type IV design in 22 cases. In all patients, the decannulation was successful, and the swallowing and deglutination functions were within the normal parameters. There was less nasal escape of the voice and the regurgitation of food than that observed using the conventional flap design method. Effective and functional reconstructions with minimal morbidities are possible with the application of the standardized forearm free flap design in oropharyngeal defects.