ABSTRACT
BACKGROUND@#TOSO, also named Fas inhibitory molecule 3 (FAIM3), has recently been identified as an immunoglobulin M (IgM) Fc receptor (FcμR). Previous studies have shown that TOSO is specifically over-expressed in chronic lymphocytic leukemia (CLL). However, the functions of TOSO in CLL remain unknown. The B-cell receptor (BCR) signaling pathway has been reported to be constitutively activated in CLL. Here, we aimed to investigate the functions of TOSO in the BCR signaling pathway and the pathogenesis of CLL.@*METHODS@#We over-expressed TOSO in B-cell lymphoma cell lines (Granta-519 and Z138) by lentiviral transduction and knocked down TOSO by siRNA in primary CLL cells. The over-expression and knockdown of TOSO were confirmed at the RNA level by polymerase chain reaction and protein level by Western blotting. Co-immunoprecipitation with TOSO antibody followed by liquid chromatography coupled with tandem mass spectrometry (IP/LCMS) was used to identify TOSO interacting proteins. Western blotting was performed to detect the activation status of BCR signaling pathways as well as B-cell lymphoma 2 (BCL-2). Flow cytometry was used to examine the apoptosis of TOSO-over-expressing B lymphoma cell lines and TOSO-down-regulated CLL cells via the staining of Annexin V and 7-AAD. One-way analyses of variance were used for intergroup comparisons, while independent samples t tests were used for two-sample comparisons.@*RESULTS@#From IP/LCMS, we identified spleen tyrosine kinase (SYK) as a crucial candidate of TOSO-interacting protein and confirmed it by co-immunoprecipitation. After stimulation with anti-IgM, TOSO over-expression increased the phosphorylation of SYK, and subsequently activated the BCR signaling pathway, which could be reversed by a SYK inhibitor. TOSO knockdown in primary CLL cells resulted in reduced SYK phosphorylation as well as attenuated BCR signaling pathway. The apoptosis rates of the Granta-519 and Z138 cells expressing TOSO were (8.46 ± 2.90)% and (4.20 ± 1.21)%, respectively, significantly lower than the rates of the control groups, which were (25.20 ± 4.60)% and (19.72 ± 1.10)%, respectively (P < 0.05 for both). The apoptosis rate was reduced after knocking down TOSO in the primary CLL cells. In addition, we also found that TOSO down-regulation in primary cells from CLL patients led to decreased expression of BCL-2 as well as lower apoptosis, and vice versa in the cell line.@*CONCLUSIONS@#TOSO might be involved in the pathogenesis of CLL by interacting with SYK, enhancing the BCR signaling pathway, and inducing apoptosis resistance.
ABSTRACT
Objective To explore the score criteria of severe hand, foot and mouth disease (HFMD) cases and to provide evidence for unified criteria and treatment on severe HFMD cases.Methods All severe cases and partial mild cases reported by two designated hospitals of HFMD in Fuyang during March to June, 2008 were scored by the methods of criteria constructed in advance.ROC curve was adopted to evaluate the score criteria and the gold standard was defined according to ICU, intubation and clinical outcomes, etc. Sensitivity, specificity and Youden' s index were used to determine the division scores on critical, severe and mild cases. Results 97% of the cases (34 cases) were scored less than 6 points. 88% of cases (24 cases) who were intubated or mechanical ventilated had the scores of 6 points or higher. 79% of deaths (11 cases) were scored 10 points or higher. The area of receiver operation characteristic (ROC) curve was 0.90 (95% CI: 0.83-0.98)between severe and mild cases and the area of ROC curve was 0.95 (95%CI: 0.92-0.98) between critical and severe, mild cases. When comprehensively considering the sensitivity and specificity,severe cases were best judged when score was 4 points (sensitivity, specificity and Youden' s index were 0.94, 0.68 and 0.62 respectively). When score was 6 points, critical cases were judged very well (sensitivity, specificity and Youden' s index were 0.92, 0.84 and 0.76 respectively). Conclusion Score criteria could be quantified to determine the degree of seriousness and with high-value for diagnosis on HFMD.
ABSTRACT
<p><b>OBJECTIVE</b>To ascertain the causation of a pregnant woman with undefined pneumonia reported from the People's Hospital of Tongling city in Anhui province on November 2005.</p><p><b>METHODS</b>Epidemiological and clinical information of the case was collected from the keypersons close to the case and referring to the medical record. A medical observation was carried out on the close contacts of the case and sick or dead poultry. Tracheal aspirates being collected were tested by both RT-PCR and real-time PCR to detect viral nucleic acids of A/H5N1, and were inoculated into special pathogen free (SPF) embryonated hens' eggs.</p><p><b>RESULTS</b>The pregnant woman was found to have been contacted with the sick/dead poultry directly on the 4th day before onset of illness. All the 122 close contacts were healthy after a 10-day medical observation. The major clinical features of the case were viral pneumonia with rapidly developed leukopenia and lymphopenia. The progress to acute respiratory distress syndrome and multiple organ dysfunction syndromes was found at clinical presentation. HA and NA gene of A/H5N1 virus were positive. The 8 gene fragments of A/Anhui/1/2005 (H5N1) isolated from the tracheal aspirates had not carried genes from a human virus through reassortment, and the receptor-binding site of the hemagglutinin was polybasic cleavage site.</p><p><b>CONCLUSION</b>This was the first documented case of H5N1 infection in pregnant woman. The immunotolerant state of pregnancy might have predisposed to the fatal outcome of the patient.</p>