In order to investigate whether polymorphism in gene for heat shock protein 70 (HSP70) has any bearing on individual susceptibility to the development of chronic obstructive pulmonary disease (COPD), the geotypes of 88 patients with COPD and 87 healthy smoking control subjects were tested by polymerase chain reaction followed by restriction fragment polymorphism analysis for HSP70 gene. In COPD group, HSP70-1 genotype A/A, A/B and B/B was 59. 1%, 35.2% and 5.7%, HSP70-2 genotype A/A, A/B and B/B was 26.1%, 54.6% and 19.3%, and HSP70-hom genotype A/A, A/B and B/B was 70.4%, 27.3% and 2.3% respectively. In the control group, it was 60.9%, 27.5% and 3.5%, 20.7%, 56.3% and 23.0%, and 54.0%, 42.5% and 3.5%, respectively. The frequency of polymorphic genetypes showed no difference between the COPD group and the control group (P>0.05). It was suggested that geneic polymorphism in HSP70 is not associated with development of COPD in Han nationality of China.
To investigate the mechanism and the suppressive effect of human cytomegalovirus (HC-MV) on colony forming unit-megakaryocyte (CFU-MK), semi-solid culture system was used to observe the effect of HCMV AD169 strain on CFU-MK's growth of 18 cord blood samples. HCMV DNA and immediate early (IE) protein mRNA in CFU-MK was detected by PCR and reverse transcription-polymerase chain reaction (RT-PCR). Our results showed that HCMV AD169 significantly suppressed the formation of CFU-MKin vitro. Compared with the mock group, the CFU-MK colonies decreased by 21.6%, 33.8% and 46.3%, respectively, in all the 3 infected groups (P<0.05), suggesting the suppression and the titer of the virus was dose-dependent. Both HCMV DNA and the expression of HCMV IE protein mRNA were positively detected in the colony cells of viral infected group,. It is concluded that HCMV AD169 strain could inhibit the differentiation and proliferation of CFU-MK by directly infecting their progenitors. There was early transcription of HCMV IE protein in CFU-MK infected by virus.
The influence of platelet-derived growth factor (PDGF) on lung development in newborn rats and the effect of retinoic acid (RA) on PDGF in lung development were investigated. Newborn Sprague-Dawley (SD) rats were randomly assigned to two groups: control group and RA group. The rats in RA group was intraperitoneally injected with all trans-retinoic acid (500 μg/kg every day) for consecutive 3 days after birth, while those in the control group were not subjected to intervention. Immunohistochemical assay was performed to locate the expression of PDGF. mRNA levels of PDGF were measured by reverse transcription polymerase chain reaction (RT-PCR) at age of 1, 3, 5, 7, 10, 14, 21 days. The method of radial alveolar counts (RAC) was used to measure the amount of the alveoli of the lungs. It was found that with increasing days, levels of PDGF-A and PDGF-B changed to verying degrees. RA could elevate significantly the expression levels of PDGF-A mRNA and protein (P<0.01), but not affect the expression levels of PDGF-B mRNA and protein markedly (P>0.05). It is suggested that PDGF might play an important role in lung development. RA can stimulate lung development through increasing the expression levels of PDGF-A mRNA and protein.
The role of MHC class II transactivator (C II TA) in constitutive or IFN-γ inducible expression of HLA molecules in human malignant hematological cell lines was investigated. The expression of HLA molecules and C II TA protein was detected by Western blot, immunohistochemistry and flow cytometry. The expression of C II TA gene was determined by RT-PCR. The capability of peripheral blood T cell reaction stimulated by tumor cells was monitored by mixed lymphocyte reaction. It was found that the HLA II-positive tumor cells expressed the C II TA quite well, and the expression of HLA I + II was increased in the tumor cells with constitutive or inducible expression of C II TA after induced by IFN-γ. The tumor cells which did not express C II TA after induced by IFN-γ were not response to the expression of HLA II promoted by IFN-γ. It suggests a correlation between the inability of some malignant hematological cell lines in response to IFN-γ for HLA expression and the deficiency in the inducible expression of C II TA, indicating C II TA might take part in the regulation of HLA I+II expression in the tumor cells, which might play an important role in tumor immunologic escape.
The transmural heterogeneous changes of transient outward potassium currents (Ito) in rabbit hypertrophic cardiomyocytes and the effects of long-term prophylactic treatment with volsartan were investigated. Rabbits were divided into hypertrophy group (left ventricular hypertrophy induced by partial ligation of abdominal aorta), vol-treated group (volsartan was administrated after the ligation), and control group (sham operated). Myocytes were isolated by a two-step enzymatical method. The sub-endocardial (Endo) and sub-epicardium (Epi) tissues were separated from midmyocardium (Mid) with a razor. Whole-cell patch-clamp technique was used to record potassium currents. The results showed that membrane capacitance was larger in hypertrophic cells than those in control and vol-treated cells (P<0.01 vs control cells,n=30). The densities of Ito in hypertrophic cells were reduced by sub-epicardium (Epi) (27.8±2.9)%, midmyocardium (Mid) (41.0±4.7)%, and sub-endocardium (Endo) (20.3±3.4)% compared with those in control cells. The decrease of Ito density was more pronounced in Mid than in Epi and Endo (P<0.01 vs Epi or Endo). There were no significant differences in Ito densities between vol-treated group and control group in three layers separately. In conclusion, volsartan can inhibit the transmural heterogeneous changes of Ito in left ventricular hypertrophic cardiomyocytes in rabbit.