Evaluation and Validation of an Enzyme-Linked Immunosorbent Assay and an Immunochromatographic Test for Serological Diagnosis of Severe Acute Respiratory Syndrome

A newly developed severe acute respiratory syndrome (SARS)-specific enzyme-linked immunosorbent assay (ELISA) was further validated to confirm cutoff values and evaluate its diagnostic performance with clinical samples. In parallel, an immunochromatographic test was also evaluated. A total of 227 clinical serum specimens collected from SARS patients were used in the study, together with 385 samples from healthy donors. By use of an immunofluorescent (IF) test as the “gold standard, ” both the ELISA and the immunochromatographic test were able to detect immunoglobulin G antibodies to SARS not only from late-convalescent-stage samples (>21 days from the onset of clinical symptoms), as previously established, but also from early-acute-phase samples (1 to 10 days from onset). The ELISA, using an optical density (OD) of 0.25 as its cutoff value, produced the best sensitivity while maintaining high specificity. It detected SARS-specific antibodies in 58, 70, 75, and 95%, respectively, of the four groups of samples collected from patients 1 to 10 days, 11 to 20 days, 21 to 30 days, and more than 30 days after the onset of clinical symptoms. Similarly, the immunochromatographic test detected SARS-specific antibodies in 55, 68, 81, and 79% of the four groups, respectively. The overall specificities for the ELISA and the rapid test were 99.5 and 97.7%, respectively. Although the positive correlation observed between the ELISA OD values and the IF titers was moderate (r = 0.6915; P < 0.001), the detection rates of both the ELISA and the rapid test were found well in agreement with the IF titers.     

Quality Assurance of Clinical MRI Scanners Using ACR MRI Phantom: Preliminary Results

Clinical magnetic resonance imaging (MRI) scanners play an important role in the diagnosis of diseases and management of patient treatment. Quality assurance (QA) of the clinical MRI scanners is mandatory to obtain optimal images in a modern hospital. In this report, the phantom test for the American College of Radiology (ACR) MRI accreditation is used as the essential part of the MRI QA protocols. Seven important assessments of MR image quality are included as follows: geometric accuracy, high-contrast resolution, slice thickness accuracy, slice position accuracy, image intensity uniformity, percent signal ghosting, and low-contrast object detectability. In addition, signal-to-noise ratio and central frequency are monitored as well. The MRI QA procedures were applied to four clinical MRI scanners in our institute twice within 3 months. According to the QA results, the service engineers were more efficient in solving scanners problems when the ACR phantom test was run.     

Epstein-Barr virus-associated smooth muscle tumor in patients with acquired immunodeficiency syndrome.

Epstein-Barr virus (EBV)-associated smooth muscle tumor (SMT) is a recognized but uncommon disease that is found to occur in patients with immunocompromised conditions such as acquired immunodeficiency syndrome (AIDS). These tumors may be multifocal and located at unusual sites, such as the brain and liver. This report describes the case of 2 AIDS patients with EBV-associated SMT and highlights the features and outcome of this rare but potentially important tumor in human immunodeficiency virus management.     

Bone morphogenetic protein receptor type II C-terminus interacts with c-Src: implication for a role in pulmonary arterial hypertension

Mutations of bone morphogenetic protein receptor type II (BMPR-II) have been associated with familial and idiopathic pulmonary arterial hypertension (PAH). BMPR-II is a member of the transforming growth factor-beta receptor superfamily. It consists of extracellular, transmembrane, and kinase domains, and a unique C-terminus with mostly unknown function. However, a number of PAH-causing mutations are predicted to truncate the C-terminus, suggesting that this domain plays an important role in the homeostasis of pulmonary vessels. In this study, we sought to elucidate the functional role of this C-terminus by seeking its interacting partners. Using yeast two-hybrid screening, we identified c-Src tyrosine kinase as a binding partner of this C-terminus. In vitro co-immunoprecipitation confirmed their interaction. Mutations truncating the C-terminus disrupted their interaction, while missense mutation within kinase domain reduced their interaction. In addition, BMPR-II and c-Src tyrosine kinase colocalized within intracellular aggregates when overexpressed in HEK293 cells. Moreover, mutations truncating the C-terminus disrupted their colocalization, whereas missense mutation within kinase domain had no effect on their colocalization. Furthermore, BMP ligand stimulation decreased c-Src-activating phosphorylation at Tyrosine 418 in pulmonary smooth muscle cells in both time- and concentration-dependent manners. Mutations that truncated the C-terminus abolished this response. Taken together, these results suggest a model in which proliferative effect of c-Src by vasoactive molecules is balanced by opposing effect of BMP signaling in basal state, and the loss of this balance due to BMPR2 mutations leads to increased c-Src activity and subsequently cell growth.     

Membrane-associated proteins of T4-infected Escherichia coli

During the prereplicative period after the infection of Escherichia coli by phage T4, more than 50 proteins are synthesized. Many of them have been identified with their corresponding genes. Among them, at least 13 are selectively enriched in the membrane preparation. They include the products of the two rII genes, genes 39, 52 (DNA-delay), and others not yet identified. The majority of these proteins (90%) are extractable by the detergent, sarkosyl, and are possibly associated with the inner or cytoplasmic membrane. Based on their electrophoretic migration in SDS-polyacrylamide gels and on their tryptic fingerprints, these proteins are found to be phage induced. Two of the newly synthesized proteins that are selectively enriched in the cell wall or outer envelope fraction are found to be identical with two envelope proteins of the host cell. They are continually synthesized after phage infection although general host protein synthesis is shut off.     

Interleukin-3, -5, and granulocyte macrophage colony-stimulating factor induce adhesion and chemotaxis of human eosinophils via p38 mitogen-activated protein kinase and nuclear factor kappaB

Hematopoietic cytokines such as interleukin (IL)-3, IL-5, and granulocyte macrophage colony-stimulating factor (GM-CSF) play a fundamental role in eosinophil functions in allergic asthma. The intracellular signal transduction mechanisms of these cytokines regulating the activation of eosinophils have been potential therapeutic targets. We investigated the roles of p38 mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-kappaB) in IL-3, IL-5, and GM-CSF-induced adhesion, morphological changes, and subsequence transmigration of human eosinophils. IL-3, IL-5, and GM-CSF could augment the phosphorylation of p38 MAPK and nucleus translocation of NF-kappaB in eosinophils. cDNA expression arrays demonstrated that the gene expression levels of several adhesion molecules including intercellular adhesion molecule-1 (ICAM-1), alpha6, beta2 integrin (CD18), and CD44 were upregulated by these cytokines. Results from functional assays showed that adhesion of eosinophils onto airway epithelial cells was enhanced after IL-3 and IL-5 but not GM-CSF stimulation. These cytokines could markedly induce shape change and augment the transmigration of eosinophils. Moreover, administration of either p38 MAPK inhibitor, SB 203580, or proteasome inhibitor, N-cbz-Leu-Leu-leucinal (MG-132), could inhibit the cytokine-induced adhesion, shape change, and transmigration of eosinophils. Together, our findings suggest that IL-3, IL-5, and GM-CSF regulated the adhesion and chemotaxis of human eosinophils through shared signaling pathways involving both p38 MAPK and NF-kappaB. Our results therefore shed light on the further development of more effective agents for allergic and inflammatory diseases.     

Comparative morphological study on the lingual papillae and their connective tissue cores (CTC) in reeves’ muntjac deer (Muntiacus reevesi)

The lingual papillae and their connective tissue cores (CTC) from Reeves’ muntjac deers (herbivorous artiodactyla) were studied using light and scanning electron microscopy and then compared to those of other mammalian species. At the posterior portion of the tongue, the Reeves’ muntjac has a lingual prominence on which large conical papillae are distributed. On the dorsal surface of the anterior tongue, numerous filiform papillae were found. Externally, each filiform papilla consists of a rod-shaped main process and several small accessory processes. Their CTCs consist of 10 or more rod-shaped processes arranged in a horseshoe pattern and several posterior processes forming a small circular pattern. This structure is a common characteristic of artiodactyla, through which Reeves’ muntjac deer can be categorized in a position in the artiodactyla class lying between the bighorn sheep and the East African bongo. Fungiform papillae are distributed among the filiform papillae on the anterior portion of the tongue. Large fungiform papillae are also sparsely distributed on the lingual prominence and have several taste buds in the epithelium on the surface. Ten or more vallate papillae are distributed at the postero-lateral area of the lingual prominence and numerous taste buds are distributed in the epithelium of their side.     

日本血吸虫多价DNA疫苗pBK-Sj26(Sj32)-Sj23免疫效果的观察

为了观察血吸虫病多价DNA疫苗的保护力,将小鼠分成5组空白对照组、空质粒对照组、单价抗原DNA疫苗pBK-CMV-Sj23组、多价抗原DNA疫苗pBK-CMV-Sj26-Sj23和pBK-CMV-Sj32-Sj23组.大量提取各组质粒DNA后,各组于0、3、5周在BALB/c小鼠股四头肌注射相应质粒DNA,9周用血吸虫尾蚴攻击感染,15周剖杀小鼠计算减虫率及减卵率.结果显示与对照组比较,实验组小鼠减虫率及减卵率有极显著性差异(P<0.01);与单价pBK-CMV-Sj23组比较,多价DNA疫苗组的减虫率及减卵率有显著性差异.提示血吸虫多价DNA疫苗诱导小鼠对血吸虫的保护力优于单价DNA疫苗.