Assessment of inflamed synovial membrane in the knee joint by dynamic magnetic resonance imaging

Dynamic magnetic resonance imaging (dynamic MRI) was used to examine the synovial membrane in the knee joints of 15 patients with rheumatoid arthritis (RA) in order to investigate the relationship between pathological and MRI findings. Signal intensities in the regions of interest (ROI), identified as the synovial membrane of the suprapatellar pouch, were measured on MR images. Signal intensities at various times after the injection of contrast medium Gd–diethylenetriaminopentoacetic acid (Gd–DTPA) were normalized relative to the signal intensity at 80s, and designated as the normalized signal intensity (NSI). Pathological findings were quantified, and the types of inflamed synovial membrane were classified as either acute or chronic. A significant difference in NSI was observed between acute and chronic types (P 0.05). Dynamic MRI was capable of classifying acute and chronic RA by measuring NSI 20s after contrast medium injection. Dynamic MRI was therefore shown to be useful for assessing regional synovial inflammation.     

Assessment of inflamed synovial membrane in the knee joint by dynamic magnetic resonance imaging

Abstract

Dynamic magnetic resonance imaging (dynamic MRI) was used to examine the synovial membrane in the knee joints of 15 patients with rheumatoid arthritis (RA) in order to investigate the relationship between pathological and MRI findings. Signal intensities in the regions of interest (ROI), identified as the synovial membrane of the suprapatellar pouch, were measured on MR images. Signal intensities at various times after the injection of contrast medium Gd–diethylenetriaminopentoacetic acid (Gd–DTPA) were normalized relative to the signal intensity at 80?s, and designated as the normalized signal intensity (NSI). Pathological findings were quantified, and the types of inflamed synovial membrane were classified as either acute or chronic. A significant difference in NSI was observed between acute and chronic types (P < 0.05). Dynamic MRI was capable of classifying acute and chronic RA by measuring NSI 20?s after contrast medium injection. Dynamic MRI was therefore shown to be useful for assessing regional synovial inflammation.     

Human fetal brain antigen expression common to tumors of neuroectodermal tissue origin

The antigenic relationship between human tumors of neuroectodermal origin and fetal brain were further investigated by characterization of two hybridoma antibodies derived from a fusion of P3-NS1/1-Ag 4-1 (NSI) myeloma cells and splenocytes hyperimmunized to second trimester human fetal brain homogenate. Monoclonal antibodies (MAs) 1H8cl 2 and 1H8cl 3 were analyzed by cell surface radioimmunoassay (CS-RIA), quantitative absorption, indirect immunofluorescence, and peroxidase-antiperoxidase (PAP) immunohistology. MA 1H8cl 3 is the more broadly reactive, binding to 9/14 glioblastoma (GBM), 2/3 neuroblastoma, 1/2 melanoma, and 1 medulloblastoma cell line(s) by CS-RIA analysis, and to 12/15 GBM, fetal brain, spleen, and liver, and adult spleen by PAP analysis. MA 1H8cl 2 is more restricted, binding to 7/14 GBM, 2/3 neuroblastoma, 1 medulloblastoma, and 2/3 fetal skin fibroblast cell line(s) by CS-RIA, and to 9/15 GBM and fetal brain and spleen by PAP analysis. Control non-central nervous system tumors and normal adult tissue including brain, thymus, lymph node, liver, kidney, lung, skin, and pancreas, were unreactive with both 1H8cl 2 and 1H8cl 3 by CS-RIA, PAP, and absorption analysis. The data presented here establish the unique nature of the detected antigenic specificities as compared to previously described oncofetal and onconeural antigens, and define two immune reagents which are operationally specific for tumors of neuroectodermal origin within the adult central nervous system.     

Clinical utility of the mBIAS and NSI validity-10 to detect symptom over-reporting following mild TBI: A multicenter investigation with military service members

Self-report measures are commonly relied upon in military healthcare environments to assess service members following a mild traumatic brain injury (mTBI). However, such instruments are susceptible to over-reporting and rarely include validity scales. This study evaluated the utility of the mild Brain Injury Atypical Symptoms scale (mBIAS) and the Neurobehavioral Symptom Inventory Validity-10 scale to detect symptom over-reporting. A total of 359 service members with a reported history of mTBI were separated into two symptom reporting groups based on MMPI-2-RF validity scales (i.e., non-over-reporting versus symptom over-reporting). The clinical utility of the mBIAS and Validity-10 as diagnostic indicators and screens of symptom over-reporting were evaluated by calculating sensitivity, specificity, positive test rate, positive predictive power (PPP), and negative predictive power (NPP) values. An mBIAS cut score of ≥10 was optimal as a diagnostic indicator, which resulted in high specificity and PPP; however, sensitivity was low. The utility of the mBIAS as a screening instrument was limited. A Validity-10 cut score of ≥33 was optimal as a diagnostic indicator. This resulted in very high specificity and PPP, but low sensitivity. A Validity-10 cut score of ≥7 was considered optimal as a screener, which resulted in moderate sensitivity, specificity, NPP, but relatively low PPP. Owing to low sensitivity, the current data suggests that both the mBIAS and Validity-10 are insufficient as stand-alone measures of symptom over-reporting. However, Validity-10 scores above the identified cut-off of ≥7should be taken as an indication that further evaluation to rule out symptom over-reporting is necessary.     

A simple and rapid method for detection of serum IgM antibodies to the rubella virus hemagglutinin

Serum IgM antibodies directed against the rubella virus hemagglutinin can be detected without prior serum fractionation. In the first step of a newly developed method, chick erythrocytes were sensitized with a subhemagglutinating dose of rubella hemagglutinin. Next, the sensitized erythrocytes were mixed with patient serum, allowing specific antibodies to react with the fixed antigens. Finally, rabbit antibodies to human IgM were used to create bridges between IgM molecules on different blood cells. The visible result was an easily read hemagglutination with sera which contain specific rubella IgM antibodies. The procedure is very simple and rapid to perform. At least 20 sera can be examined in approximately 2 h. No sophisticated instruments are needed.We have tentatively called the new method rubella anti-IgM hemagglutination (HA). Rubella antiIgM HA was more sensitive than the standard density gradient centrifugation/hemagglutination inhibition technique, but the correlation between the methods was good. Non-specific inhibitors of hemagglutination or rheumatoid factors did not seem to interfere with the specificity of the new method, and competition for antigenic sites between antibodies from the IgG/IgA and IgM classes did not seem to represent a serious, practical problem.     

Genotypic and phenotypic analysis of the env gene from South African HIV-1 subtype B and C isolates

The objective of the study was to assess the genotypic and phenotypic properties of 18 viral strains from human immunodeficiency virus-1 (HIV-1) positive patients and to identify subtype C isolates for vaccine design strategies. All the isolates were non-syncytium-inducing (NSI) in both the primary and MT-2 cell cultures. The amino acid charge of the V3 loop correlated with the NSI phenotype of the strains. The V3 competitive peptide enzyme immunoassay and DNA sequencing of the partial gp120 region gave concordant results on the 15 subtype C strains, whereas the three B genotypes gave a positive to B, a nonreactive to B, and a dual reaction to the B-D peptides, respectively. Sixteen of the isolates used only CCR5 as coreceptor whereas two isolates made use of additional coreceptors including CXCR4. In summary, all our subtype C isolates are NSI phenotypically and almost all of them use CCR5 exclusively as their coreceptor.     

Impact of food processing on the safety assessment for proteins introduced into biotechnology-derived soybean and corn crops

The food safety assessment of new agricultural crop varieties developed through biotechnology includes evaluation of the proteins introduced to impart desired traits. Safety assessments can include dietary risk assessments similar to those performed for chemicals intentionally, or inadvertently added to foods. For chemicals, it is assumed they are not degraded during processing of the crop into food fractions. For introduced proteins, the situation can be different. Proteins are highly dependent on physical forces in their environment to maintain appropriate three-dimensional structure that supports functional activity. Food crops such as corn and soy are not consumed raw but are extensively processed into various food fractions. During processing, proteins in corn and soy are subjected to harsh environmental conditions that drastically change the physical forces leading to denaturation and loss of protein function. These conditions include thermal processing, changes in pH, reducing agents, mechanical shearing etc. Studies have shown that processing of introduced proteins such as enzymes that impart herbicide tolerance or proteins that control insect pests leads to a complete loss of functional activity. Thus, dietary exposure to functionally active proteins in processed food products can be negligible and below levels of any safety concerns.     

Diffusion weighted imaging and neuropsychological correlates in adults with mild traumatic brain injury

Diffusion Tensor Imaging (DTI) is increasingly being used as a research tool in mild Traumatic Brain Injury (mTBI). This article reviews the concepts of diffusion tensor imaging, neuropsychological testing and results to date when applied to mTBI in adults. DTI is being used in conjunction with neuropsychological and electrophysiological measures to provide improved structural/functional correlations of mTBI. Future directions and applications of DTI in mTBI research are suggested.