Volume 114  ·   Issue 02  ·  2001

Objective To evaluate the long-term therapeutic effects of autologous peripheral blood stem cell transplantation (auto-PBSCT) on the treatment of hematological and solid tumors. Methods Fifty-one patients were recruited in this auto-PBSCT study, in which several potentially important parameters were studied including the optimal time for stem cell collection, the dose of stem cell reinfusion,the time of hematopoietic reconstitution, the disease free survival (DFS) and overall survival (OS),complications related to transplantation, and maintenance chemotherapy after auto-PBSCT. Results After APBSCT, 3-year and 5-year survival rates of NHL were 83.3%; those of AML were 74.7%; those of MM were 37.9%and 19%; those of ALL were 40%and 0%respectively. Hematopoietic reconstitution was greatly promoted by granulocyte colony stimulating factor (G-CSF). The mean time for patients' neutrophil to recover up to> 0.5 x 109/L after APBSCT was 11.14 days in the group of the patients receiving G-CSF in contrast to 17.6 days in the group receiving no G-CSF. The most common complications of transplantation were fever, liver dysfunction and hypokalaemia, which were curable. No death was due to transplantation related complications. Conclusion Comparing with conventional chemotherapy, our study suggests that auto-PBSCT is a very important therapeutic option that can significantly improve the prognosis in the patients with hematological and solid tumors, especially in the patients with AML and NHL. Chin Med J 2001; 114(2): 196-199

Objectives To investigate the efficacy of accelerating hemopoietic reconstraction and reducing a graft versus host disease (GVHD) in Allo-BMT receiving lenograstim stimulated donor marrow and to assess the preliminary biological mechanism . Methods The donors for thirty patients (study group) with leukemia were given lenograstim 3-4 μg·kg-1·d-1 for seven days prior to marrow harvest. The results of subsequent engraftment in the recipients was compared with fifteen donors without G-CSF (control group). Five donors themselves were studied to assess the effects of lenograstion on hematopoietic progenitor cells and lymphocyte subsets in BM. Results The stimulated bone marrow contained a higher number of nucleated cells, CFU-GM and CD34+cells (P<0.01). The hematopoetic reconstitution was accelerated. Until granulocyte counts exceeded 0.5x 109/L and plalete counts exceeded 20 x 109/L, the days were 16.7 ± 3.2 and 18.4 ± 3.0 days as compared with those of the control group (22.5±5.1 and 26.3±5.9 days respectively, P<0.01). The incidence of grade Ⅱ -Ⅳ aGVHD was very low, only one case with grade Ⅱ aGVHD on the skin in the study group. Four out of fifteen patients (26.7%) in the control group had grade Ⅱ-Ⅳ aGVHD (P<0.05). The number of T lymphocyte subsets in the harvested BM stimulated by G-CSF changed. In comparison with the control group, CD4+ decreased and CD8+ increased significantly (P <0.01). The changes of progenitor cells and T lymphocyte subsets in BM from pre- to post- G-CSF stimulation indicated that the percentage of CD4+ cells reduced (P <0.05), that of CD8+ cells, and that of CD34+ increased (P <0.01). The incidence of chronic GVHD and relapse of leukemia were not different significantly between both groups. Conclusions Allogenic bone marrow transplant (Allo-BMT) donors given G-CSF can accelerate engraftment and minimize the incidence of severe aGVHD. There is a trend in favour of improved transplant-related complicatians. Chin Med J 2001; 114 (2): 191-195

Objective Recombinant human pro-urokinase forms insoluble inclusion body when overexpressed in Escherichia coli. It must be denatured and renatured in vitro so that it can acquire activity. This study aimed at increasing the renaturation yield of denaturant pro-urokinase. Methods We evaluated the basic renaturation conditions of pro-urokinase through qualitative and quantitative analysis of pH, temperature, denatured concentration, protein concentration, and the ratio of reduced and oxidized thiol reagents. We also compared the effects of nonspecific additives, step-wise dilution and urea gradient dialysis. Results We defined the optimal conditions of pro-urokinase renaturation with a yield of about 20%-30%. Conclusion Different recombinant denatured proteins have different renaturation conditions due to their different molecular sizes, molecular constructions, disulfide bond numbers, and hydrophobicity. The renaturation yield can be increased by optimizing the renaturation conditions of a specific protein. Chin Med J 2001; 114(2): 186-190

Objective To explore the molecular mechanism underlying the decreased velocity of tension rise in rat myocardium during congestive heart failure (CHF) and left ventricular hypertrophy (LVH) induced by aortic stenosis. Methods The maximum velocity of tension rise (+dT/dtmax) was measured in left ventricular papillary muscle and the mRNA level of myosin heavy chain (MHC) isoforms in the left ventricle were detected by Northern blot analysis. Results The value of + dT/dtmax in CHF and LVH group were 64.17%and 37.15%lower than sham-operated controls (Sham) (P<0.01); values in the CHF group were 42.99%lower than that of LVH (P<0.01) . The level of α-MHC mRNA in LVH was not different from that of the Sham (P> 0.05), but decreased significantly in CHF to 42.3%of Sham and 56.1 %of LVH (P <0.01) . The level of β-MHC mRNA was up-regulated by 88.3%(P <0.01) in LVH compared with Sham and the level of β-MHC in CHF was 1.5-fold and 3.7-fold higher than that in LVH and Sham respectively (P<0.01). The ratio of α-MHC/β-MHC mRNA in LVH and CHF decreased to 42.4%and 9.8%respectively of the value in Sham (P<0.01). Correlation between α-MHC/β-MHC mRNA level and + dT/dtmax was analyzed which showed that these values were positively correlated with a correlation coefficient of 0.875 (P <0.01). Conclusion The decreased ratio of a-MHC/β-MHC mRNA was the major molecular mechanism underlying the decreased + dT/dtmax in CHF and LVH myocardium. The decreased ratio of a-MHC/β-MHC mRNA in LVH was mainly due to the up regulation of β-MHC mRNA while in CHF both down regulation ofα-MHC and up regulation of β-MHC were involved. Chin Med J 2001; 114(2): 183-185

Objective To develop a cellular model of preconditioning by a brief period of hypoxia in isolated guinea pig cardiomyocytes and to determine whether or not an ATP sensitive K+(KATP) channel is involved in ischemic preconditioning. Methods Single myocytes were isolated from the ventricle of adult guinea pigs. The experimental chamber allowed the cells to be exposed to low O2 pressure. During hypoxic preconditioning, the cells were equilibrated with normaxic solution for 10 minutes and then exposed to hypoxia for 5 minutes, followed by 10minutes of reoxygenation. The cells were then subjected to 20 -180 minutes of hypoxia and reoxygenation. Ionic currents were studied with the patch clamp technique in whole-cell and cell-attached configurations. Results A 5-minute hypoxic preconditioning offered a significant protection from cell injury in subsequent hypoxia-reoxygenation. After a latency of more than 15 minutes, hypoxia induced a time-independent outward K+ current which could be blocked by 5 μmol/L glibenclamide. At 10 mV, the current increased from 78±15 pA to 1581 ± 153 pA (P <0.01, n=18) . However, the latency to develop KATP channel currents (IKATP) was greatly shortened in preconditioned cells, and the current was increased acceleratively. At 10 mV, the current more than 4 nA was recorded in preconditioning cells. In the single channel recordings, the time interval from the first channel opening to maximum opening was also markedly abbreviated in preconditioned cells. Conclusion Isolated guinea pig cardiomyocytes can be preconditioned with a brief period of hypoxia. This hypoxic preconditioning may modify the KATP channel, and make the channel open more readily during the second hypoxia. Chin Med J 2001; 114(2): 178-182

Objective To determine whether continuous or cyclic hormone replacement therapy (estrogen and progestogen) is better. Methods One hundred and forty Sprague-Dawley rats were randomly divided into seven groups. The 1st and 2nd groups were normal estrous and ovariectomy (OVX) controls. Treatment of the other groups imitated the clinical regimen (continuous and cyclic) with estradiol valerate (E2V) and medroxy progesterone (MPA) in different ratios of combination. The rats were sacrificed and sections of uterus were stained with HE and histochemical metheds to detect mitosis and proliferating cell nuclear antigen (PCNA), respectively. The mitotic index (MI) and PCNA index were calculated. Results The MI and PCNA index were similar in luminal and glandular cells. Both markers were low in the two control groups. When E2V was given for 1 to 6 days, both the MI and PCNA index increased with duration of treatment. When MPA was added, both markers were reduced to a very low level. In the continuous regimen, both markers decreased as the MPA dosage increased. The ratio of E2V: MPA=1:0.5 was enough to suppress markers to a low level similar to that of normal estrous rats. A further increase in the ratio to 1:1.0 showed no further decrease in PCNA index. In the cyclic regimen, MPA was added for the last 5 days. The mitotic index reached a significantly low level near 0 in all ratios, but the PCNA index in each subgroup was still as high as the positive control, even though the dosage of MPA was increased several times to 1: 8.0. When MPA was added for the last 10 days, the PCNA index at a ratio of 1:4.0 could be reduced to a low level. Conclusion The results of this study suggest that the continuous regimen was better than the cyclic regimen in postmenopausal hormone replacement therapy (HRT). Progestin should be given for at least 10days in the cyclic regimen. Chin Med J 2001; 114(2): 173-177

Objective To explore the immune promotion mechanism of retinoic acid (RA). Methods Reverse Transcription-Polymerase chain reaction (RT-PCR) was used to detect the gene expression of insulin like growth factor I (IGF-I) and IGF receptors (IGF-IR and IGF-IIR) in vitro, and their regulation by RA in human cord blood lymphocyte (CBL). Results Significant upregulation of IGF-I, IGF-IR and IGF-IIR mRNA was found at 6-24 hours in CBL incubated with physiologic concentrations of RA as compared to those without RA. Conclusion The enhancement of IGF expression may be an important pathway for vitamin A to promote immune cellular functions. Chin Med J 2001; 114(2): 170-172

Objective To investigate the relationship between muscular asthenopia post photorefractive keratectomy(PRK) and eccentric ablation. Methods 16 eyes of 8 myopia cases whose muscular asthenopia was corrected by subjectively accepted triangular prism after PRK with vision more than 0.8 were followed up for 6-14 months. On the basis of data provided by the pre-PRK, post-PRK and their difference corneal topography, we calculated the real corrected corneal diopter (D) with the Holladay formula and measured the ablating eccentricity (h) and its direction. According to the formula δ≈Dh, the prism effective value (δ) caused by the eccentric ablation was computed and compared with objectively accepted triangular prism. Results The subjectively accepted prism was similar to values calculated from the formula. Their mean difference is 0.10 ±0.25. The direction of the subjectively accepted prism was in the direction of ablation deviation. Conclusions Eccentric ablation was the chief cause of post-PRK muscular visual asthenopia. The triangular prism effective value from eccentric ablation may be estimated by the formula δ≈Dh. We must pay attention to the diagnosis, treatment and prevention of post-PRK muscular asthenopia. Chin Med J 2001; 114(2): 167-169

Objective To detect if Fas is expressed in human renal interstitial fibroblasts (hRIFs) and apoptosis of hRIFs can be induced by specific anti-Fas antibody. Methods hRIFs were cultured from isolated papillae of human kidney, and identified by morphologic examination, assay of antigenic components and culture in D-valine selective medium. Fas expression in normal hRIFs was detected by RT-PCR and immunocytochemistry staining. After hRIFs were incubated with interferon gamma (γ-IFN 500 U/ml, 1000 U/ml, 1500 U/ml and 2000 U/ml, respectively) for 48 hours,Fas expression was determined by Northern blot, Western blot and flow cytometry. hRIFs pre-stimulated with γ-IFN (500 U/ml, 48 hours) were incubated with anti-Fas antibody (IgM, 0.5 μg/ml) for 12 hours. And apoptosis was identified by morphologic examination. DNA ladder assay and flow cytometry. Results The cultured hRIFs showed a shuttle-like shape and were positively stained by labeled anti-vimentin antibody but negatively stained by anti-epithelial membrane antibody. They could not grow in the D-valine selective medium and died partly in a week. Fas mRNA and protein were expressed in normal hRIFs and markedly upregulated by stimulation with γ-IFN. Apoptosis in γ-IFN pre-stimulated hRIFs was induced by anti-Fas antibody, showing cell nuclear shrinkage and condensation in morphologic feature,internucleosomal DNA fragmentation in DNA ladder assay and a pick of hypo-diploid nuclei by flow cytometry. Conclusion Fas is normally expressed in hRIFs and can be markedly upregulated by γ-IFN. Anti-Fas antibodies can induce apoptosis of hRIFs pre-stimulated with γ-IFN. Chin, Med J 2001; 114(2): 162-166

Objective To examine the relationship between spontaneous abortion and chromosomal abnormalities. Methods Couples who had one or more consecutive spontaneous abortions and had normal genitals were enrolled for cytogenetic karyotype analysis. Results In the 61 couples, the detected incidence was 11.5%, with five Robertsonian translocations,one reciprocal translocation, and one pericentric inversion of chromosome 7. Conclusion Chromosomal abnormalities may play an important role in fetal wastage. Chin Med J 2001; 114(2): 200-201