PAK5 is a potential target in myelodysplastic syndrome through interacting with LMO2 and GATA1.

Myelodysplastic syndrome (MDS) is a neoplastic heterogeneous and pre-leukemic disease with poor clinical outcome due to the failure of current chemotherapeutic strategies to target leukemic stem cells. Recently, we find that p21-activated kinase 5 (PAK5) overexpresses in MDS patients and leukemia cell lines. The clinical and prognostic value of PAK5 in MDS is unclear although it has anti-apoptosis ability and can promote cell survival and mobility in solid tumors. In this study, we find that LMO2 is co-expressed with PAK5 in the aberrant cells from MDS, and mitochondria-localized PAK5 can translocate into cell nucleus upon fetal bovine serum stimulation to interact with LMO2 and GATA1, which are important transcription regulators in hematological malignancies. Interestingly, without LMO2, PAK5 fails to bind GATA1 and facilitate GATA1 Ser161 site phosphorylation, indicating that PAK5 may be a key kinase in LMO2-associated hematopoietic diseases. Moreover, we find that PAK5 protein level in MDS is significantly higher than leukemia, and the data of 2095 leukemia samples from 'BloodSpot' database shows that PAK5 mRNA level in MDS is also increased obviously. Taken together, our findings suggest that PAK5-targeted strategies in clinical therapy have a potential value on MDS intervention.

Diagnostic value and dynamic variance of serum antibody in coronavirus disease 2019.

OBJECTIVE: To investigate the diagnostic value of serological testing and dynamic variance of serum antibody in coronavirus disease 2019 (COVID-19). METHODS: This study retrospectively included 43 patients with a laboratory-confirmed infection and 33 patients with a suspected infection, in whom the disease was eventually excluded. The IgM/IgG titer of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was measured by chemiluminescence immunoassay analysis. RESULTS: Compared to molecular detection, the sensitivities of serum IgM and IgG antibodies to diagnose COVID-19 were 48.1% and 88.9%, and the specificities were 100% and 90.9%, respectively.In the COVID-19 group, the IgM-positive rate increased slightly at first and then decreased over time; in contrast, the IgG-positive rate increased to 100% and was higher than IgM at all times. The IgM-positive rate and titer were not significantly different before and after conversion to virus-negative. The IgG-positive rate was up to 90% and not significantly different before and after conversion to virus-negative. However, the median IgG titer after conversion to virus-negative was double that before, and the difference was significant. CONCLUSIONS: Viral serological testing is an effective means of diagnosis for SARS-CoV-2 infection. The positive rate and titer variance of IgG are higher than those of IgM in COVID-19.

[A study of double antigen sandwich colloidal gold immunochromatography rapid detection for Mycobacterium tuberculosis antibody].

OBJECTIVE: To establish a simple, fast and accurate double antigen colloidal gold immunochromatographic technique for detecting Mycobacterium tuberculosis antibody from tuberculosis patients. METHODS: The fusion protein ESAT-6-16-38 was constructed by using gene cloning technique for the 6, 16 and 38 kDa early secreted antigenic target from Mycobacterium tuberculosis. The ESAT-6-16-38 fusion protein was marked to colloidal gold to establish the double antigen colloidal gold immunochromatographic assay. Serum samples from 163 patients with tuberculosis, including 57 sputum-positive cases, 64 sputum-negative cases, and 42 cases with extrapulmonary tuberculosis, were collected during 2007 and 2009 from the Disease Prevention and Control Center of Deqing County. In addition, 573 controls (224 healthy volunteers, 217 patients with acute pneumonia and bronchitis, 132 patients with paragonimiasis) were recruited for comparison. Mycobacterium tuberculosis specific antibodies were detected by using immunochromatographic and protein chip technique. Detection rate was compared with Chi-square test. RESULTS: Among the 163 tuberculosis patients, the positive rates of immunochromatographic detection and protein chip were 73.0% (120/163) and 72.4% (118/163) respectively; the difference was not statistically significant (χ()2 = 0.062, P > 0.05). Among the 573 controls, the negative rates of immunochromatographic detection and protein chip were 93.9% (538/573) and 92.0% (527/573) respectively; the difference was not statistically significant (χ()2 = 0.635, P > 0.05). There was no cross reaction in the paragonimiasis patients. The positive rate of the immunochromatographic assay was as high as 87.7% (50/57) in the sputum-positive patients. CONCLUSIONS: The double antigen immunochromatographic technique is an easy to operate, rapid, highly sensitive, specific, and reproducible method for the detection of Mycobacterium tuberculosis antibodies.

Protective effects of the aqueous extract of Scutellaria baicalensis against acrolein-induced oxidative stress in cultured human umbilical vein endothelial cells.

CONTEXT: Scutellaria baicalensis Georgi (Labiatae) (SbG), one of the fifty fundamental herbs of Chinese herbology, has been reported to have anti-asthmatic, antifungal, antioxidative, and anti-inflammatory activities. OBJECTIVE: This study was designed to determine the protective effects of the extract of SbG against the acrolein-induced oxidative stress in cultured human umbilical vein endothelial cells (HUVEC). MATERIALS AND METHODS: The MTT reduction assay was employed to determine cell viability. The total cellular glutathione (GSH) level was detected using a colorimetric GSH assay kit. Cellular GSH production was conducted by detecting the mRNA expression levels of γ-glutamylcysteine ligase catalytic subunit and modifier subunit. RESULTS: Concentration-dependent cytotoxic effects of acrolein were observed while SbG could effectively protect the acrolein-induced oxidative damage. The protective mechanism was investigated, showing that the increased GSH content in the SbG-incubated HUVE cells was associated with the protective effects of SbG-treated cells. Further RT-PCR data confirmed the elevated mRNA expressions of GSH synthesis enzymes. DISCUSSION AND CONCLUSION: The current study strongly indicated that SbG could be a potential antioxidant against oxidative stress in treating cardiovascular diseases.