Erythropoietin and cardiocirculatory condition in aged patients with chronic renal failure

BACKGROUND/AIM: The clearest benefit of recombinant human erythropoietin (rHuEPO) in end-stage renal disease is a substantial reduction in transfusion dependency and an improved quality of life. In this report, we describe the efficacy of weekly subcutaneous administration of rHuEPO in 11 elderly patients with anemia secondary to chronic renal failure. METHODS: The role of rHuEPO therapy in increasing the patient's quality of life and in decreasing the hospitalization rates secondary to cardiac morbidity was verified in 11 elderly patients (age range between 66 and 85 years) with anemia due to chronic renal failure. The mean hemoglobin level at the beginning of the study was 8.2 +/- (SD) 0.7 g/dl, and the serum creatinine concentration was 4.8 +/- 1.36 mg/dl. The patients underwent baseline and annual echocardiography, in addition to an electrocardiogram. RESULTS: Most patients experienced a partial regression of left ventricular hypertrophy, and no congestive heart failure was documented. The mean hemoglobin level during rHuEPO therapy increased to 11.3 +/- 1.2 g/dl, while the mean serum creatinine concentration did not change significantly. CONCLUSIONS: Our results confirm that early anemia correction in aged chronic renal failure patients permits improvement of the quality of life, of exercise performance, and of cognitive functions. Reduced transfusion need and regression of left ventricular hypertrophy favor a minor incidence of cardiac morbidity and contribute to reduce health costs.     

Effects of erythropoietin-gene electrotransfer in rats with adenine-induced renal failure

BACKGROUND: We previously demonstrated that erythropoietin (Epo) expression increases in five-sixths nephrectomized rats, after muscle-targeted gene transfer by in vivo electroporation, using plasmid DNA expressing rat Epo (pCAGGS-Epo). Here, we apply this method to a rat model with severe anemia associated with chronic renal failure; these rats have hematocrit levels in the 30-35% range, similar to those in humans with end-stage renal disease. METHODS: Wistar rats were treated to produce adenine-induced uremia. The uremic rats were then treated with muscle-targeted gene transfer using pCAGGS-Epo. Some uremic rats died from chronic renal failure; one of these was dissected, and the kidneys were histologically examined. For the remaining rats, we measured body weight and blood pressure, and obtained blood samples regularly. RESULTS: The uremic rats showed severe anemia, with hematocrit levels at 32.6 +/- 3.3%. Epo-gene transfer increased Epo expression and serum Epo levels, and also increased the hematocrit levels to 64.5 +/- 4.8%. The dose of pCAGGS-Epo used in this study did not induce severe hypertension. CONCLUSIONS: Continuous Epo-gene expression improves the anemia associated with chronic renal failure, and without severe side effects. Our results support the potential use of gene electrotransfer for human gene therapy applications.     

Cardiovascular hemodynamic effects of correction of anemia of chronic renal failure with recombinant-human erythropoietin

The results of 8 to 12 weeks of treatment of the anemia of uremia with rHuEPO in patients with chronic renal failure and uremia are: a sustained increased hematocrit; increased RBC mass, and subsequent increased MAP; and increased TPRI. The observed trends of decreased LVEF, and echo Doppler evidence of a trend toward LV systolic and diastolic dysfunction, although not individually statistically significant, represent 3 separate evaluation techniques coupled with hypertension and TPRI increase during administration of rHuEPO to increase the hematocrit and packed red blood cell volume in patients with chronic renal failure and anemia. Increased TPRI and hypertension associated with correction of uremic anemia vasodilation and the increased blood viscosity have been noted in earlier investigations with transfusions. The hypertension and elevated TPRI demonstrated during rHuEPO therapy in patients with progressive chronic renal failure associated with increased hematocrit, and the trends toward systolic and diastolic cardiac dysfunction are noted herein. These changes were associated with the combined increase of packed RBC mass and plasma volume in this study. The natural progressive course of worsening of renal function exhibited by these patients could have limited their ability to regulate plasma volume, making them vulnerable to volume-dependent hypertension and a significant preload adding to potential cardiac dysfunction in addition to the increased TPRI.     

Erythropoietin and anemia

Recombinant human erythropoietin (rHuEPO) has revolutionized the treatment of anemia of chronic renal failure. RHuEPO has been shown to increase survival, decrease hospitalizations, improve brain and cognitive function, and improve quality of life for renal patients. Much has been learned about the normal and pathologic physiology of anemia because rHuEPO has become available to investigators, and this has been widely applied. Additional work is needed in better defining the sites of production of endogenous EPO as well as the nature and control of the oxygen sensor(s) in the kidney. Remaining clinical issues related to this remarkable compound include predicting and overcoming resistance; avoiding iron deficiency; determining the appropriate target hemoglobin; increasing the use strategies such as subcutaneous administration to increase efficiency; and devising a more rational payment scheme.     

Correction of anemia in uremic mice by genetically modified peritoneal mesothelial cells

BACKGROUND: During peritoneal dialysis, mesothelial cells become detached from the peritoneum and accumulate in the dialysate. Our aim was to evaluate the potential of peritoneal effluent (PF)-derived human peritoneal mesothelial cells (HPMC) as target for gene therapy. We used erythropoietin (EPO) as our target gene. METHODS: Various extracellular matrixes (ECM) were tested for optimal adhesion and growth of HPMC. The EPO gene was introduced to mouse peritoneal mesothelial cells (MPMC) and HPMC by transfection or retroviral transduction. EPO secretion from PMC was measured by enzyme-linked immunosorbent assay (ELISA) and by the TF-1 cell proliferation assay. We performed intraperitoneal or intramuscular transplantations of the genetically modified cells into regular or 5/6 nephrectomized Balb/c mice and nude mice. Finally, we measured serum EPO and hematocrit levels. RESULTS: ECM-coated plates provided up to sixfold increase in the efficiency of PMC isolation from PF. Gelatin coated dishes (20 microg/cm2) were found optimal for isolation of PF-HPMC. RPR-120535 liposome was found to be best for PMC transduction. In vitro studies showed EPO secretion from modified HPMC over 6 months. Intraperitoneal transplantation aided with collagen matrix was the most effective. EPO, in MPMC transplanted mice, was detected up to 3 weeks (peak at 13 +/- 1 mIU/mL), and anemia of uremic mice was corrected (35.3 +/- 0.9 mIU/mL to 41.9 +/- 1.1 mIU/mL). CONCLUSION: PF-HPMC can be considered as an appropriate target for gene therapy since these cells can be efficiently isolated, modified, and transplanted. Nevertheless, implantation techniques in the peritoneum should be directed at obtaining longer duration of transgene expression in vivo, and means should be developed for enabling regulated expression of the gene.     

Once weekly versus twice weekly subcutaneous administration of recombinant human erythropoietin in patients on continuous ambulatory peritoneal dialysis.

Twice weekly subcutaneous (s.c.) administration of recombinant human erythropoietin (rHuEPO) is effective in reversing renal anemia in CAPD patients. However the optimal frequency of administration has not been established. It would be more convenient to give rHuEPO by once weekly rather than twice weekly injection. We have therefore compared the effect of twice weekly versus once weekly s.c. administration of rHuEPO. Two groups of 10 CAPD patients were given the same starting dose of s.c. rHuEPO (100 U/kg body wt/week) either as a single weekly dose or twice weekly in divided doses. The rHuEPO dosage was then adjusted according to the hematologic response. The aim was to increase hemoglobin levels by about 1 g/dl per month. The target hemoglobin was 10 g/dl. After 16 weeks of treatment with rHuEPO, the hemoglobin levels rose from 6.6 +/- 1.2 (mean +/- SD) to 10.1 +/- 1.1 g/dl in the once weekly group and from 6.4 +/- 0.8 to 10.2 +/- 1.1 g/dl in the twice weekly group. The average doses of rHuEPO used during the study were 84 +/- 16 and 88 +/- 15 U/kg body wt/wk for the once weekly and twice weekly groups respectively. Subcutaneous administration of low dose rHuEPO is effective in reversing renal anemia. Similar responses were obtained with once weekly and twice weekly regimens. It is therefore acceptable and convenient for patients to receive one weekly s.c. injection of rHuEPO for the treatment of renal anemia.     

Once weekly versus twice weekly subcutaneous administration of recombinant human erythropoietin in haemodialysis patients.

Optimal route and frequency of administration of recombinant human erythropoietin (rHuEPO) have not yet been determined. There is some evidence to suggest that subcutaneous administration of rHuEPO may be more effective than the intravenous route in reversing renal anemia. It is also unclear whether rHuEPO is more effective when given by a large intermittent dose or by more frequent multiple divided doses. We have compared the effect of twice weekly versus once weekly subcutaneous administration of rHuEPO in two groups of haemodialysis patients. At the end of 12 weeks of treatment with rHuEPO, the mean haemoglobin levels had risen from 6.9 +/- (SD) 0.7 to 8.9 +/- 1.3 g/dl in the once weekly group and from 7.2 +/- 1.0 to 9.3 +/- 1.6 g/dl in the twice weekly group. The average doses of rHuEPO used during the study were 127 +/- 6 and 115 +/- 18 U/kg body weight/week for the once weekly and twice weekly groups, respectively. Subcutaneous administration of low-dose rHuEPO is effective in reversing renal anaemia. Similar responses were obtained with once weekly and twice weekly regimens.     

Possible influence of vitamin D receptor gene polymorphisms on recombinant human erythropoietin requirements in dialysis patients

BACKGROUND: Vitamin D receptor (VDR) gene polymorphisms have been widely studied, especially to analyze their effects on calcium-phosphorus metabolism and secondary hyperparathyroidism in patients on dialysis. In this study, we sought to investigate the possible effects of these polymorphisms on the anemia of renal failure and recombinant human erythropoietin (rHuEPO) responses among patients receiving hemodialysis. METHODS: One hundred twenty-eight patients (52 females/76 males) underwent genotyping for the insertion/deletion Bsml (B-->b, restriction site, exon VIII-->IX) and Tagl (T-->t, 352 exon IX) VDR gene polymorphisms. The mean value of the last 6 months' monthly evaluated laboratory values (C-reactive protein, hemoglobin, iron indices, PTH, and albumin) and clinical findings (rHuEPO requirement, cumulative iron supplementation doses, and body weight) were analyzed retrospectively excluding patients with chronic inflammation, hemolytic anemia, or active blood loss such as gastrointestinal bleeding. RESULTS: Mean age and dialysis durations were 41.5 +/- 11.8 years and 91.8 +/- 45.3 months, respectively. Polymorphism percentages were as follows: Bsml; BB/Bb/bb: 32.2/63.6/4.2 and Tagl; TT/Tt/tt: 40.5/55.4/4.1%, respectively. BB variant of Bsml gene was related to lower rHuEPO needs (P < .05) and also higher hemoglobin levels (P < .005) when compared with the Bb/bb variant. Considering Tagl variants, transferrin saturation levels were lower (P < .03) among patients with the Tt/tt variant, but there was no other significant difference in the mean values of other data between TT and Tt/tt variants. CONCLUSION: The BB variant of Bsml was related to decreased rHuEPO requirements to achieve higher hemoglobin levels among maintenance hemodialysis patients without chronic inflammation.     

Intravenous iron dextran and erythropoietin use in pediatric hemodialysis patients

Recombinant human erythropoietin (rHuEPO) is an effective treatment for the anemia of chronic renal failure. However, adequate availability of iron is necessary for an optimal response. We prospectively evaluated the effect of an intravenous iron protocol in a pediatric hemodialysis unit. Patients with either a serum ferritin less than 150 ng/ml or transferrin saturation (TSAT) less than 20% received intravenous iron dextran during ten consecutive dialysis sessions. The administration of rHuEPO was adjusted using a protocol designed to maintain patient hematocrit between 33% and 36%. Thirteen courses of intravenous iron were evaluated. Patients received 4 mg/kg of iron dextran (maximum of 100 mg) during each of ten consecutive dialysis sessions. In 12 cases there was a decrease in rHuEPO use 2 months after completing the course of intravenous iron. The mean rHuEPO dose decreased from 3,784 units to 2,115 units (P<0.005). Based on the criteria of response to intravenous iron, a percentage iron saturation of less than 20% had a high specificity for detecting iron deficiency. All patients who received a course of intravenous iron had a TSAT less than 20%. The measurement of serum ferritin was less useful in our patients.     

Autologous blood transfusion with recombinant human erythropoietin in heart surgery--studies on the volume of preoperative donation and postoperative administration]

Recombinant human erythropoietin (rHuEPO) was administered to 42 elective heart surgery patients, and the volume of autologous blood donated within the preoperative short period and effects of improving anemia by postoperative rHuEPO administration were studied. rHuEPO (100 U/kg/day) and chondroitin sulfate-iron (40 mg/day) were given intravenously for preoperative 14 days, and each 400 ml of autologous blood was donated on the 14th and 4th day before operation. Reticulocytes increased significantly 3 days after administration (p less than 0.01). The hemoglobin level, 13.4 +/- 1.0 g/dl before the first donation, returned to 13.4 +/- 1.1 g/dl just before operation. 800 ml of autologous blood, needed for usual open heart surgery, may possibly have been donated within 14 days without making patients anemic by intravenous rHuEPO administration. For postoperative rHuEPO administration, the patients were divided into 3 groups: Group I (10 cases): given for 14 days, Group II (12 cases): for 7 days, Group III (20 cases): no administration. Reticulocytes decreased rapidly after termination of rHuEPO administration in each group, and on the 7th day after termination, they returned to the level before administration. The hemoglobin level in Group I was maintained after termination of rHuEPO, and was +2.2 +/- 1.1 g/dl on the 21st postoperative day compared with the level of 1st postoperative day. The hemoglobin level in Group II fell after termination and was +0.9 +/- 0.7 g/dl on the 21st day, this being comparable to the level of Group III. There were significant differences between Group I and II (p less than 0.05), and between Group I and III (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Anemia management in chronic heart failure: lessons learnt from chronic kidney disease

The importance of anemia in chronic kidney disease (CKD) has become increasingly well recognized over recent years, as have the benefits of treating anemic CKD patients with recombinant human erythropoietin (rHuEPO, epoetin). As well as reducing the need for blood transfusions and the complications associated with renal failure in CKD patients, rHuEPO treatment decreases patient morbidity and mortality, particularly as a result of cardiovascular disease. The strong correlation between anemia, renal failure and cardiac failure is one that has received much attention recently, with each factor recognized to cause the other to worsen in a 'vicious cycle'. Recent studies have concentrated on the possible benefits of anemia treatment in patients with CHF. Currently available data suggest improvements in CHF symptoms, left ventricular ejection fraction (LVEF) and a reduction of hospitalizations associated with anemia correction through epoetin treatment. Available data from CKD patients suggest that anemia management should begin as early as possible, although the optimal target level for individual patients is as yet unclear. In addition to the currently available evidence, additional large, randomized, controlled studies are required to further define the morbidity/mortality benefits of epoetin treatment in CHF patients with anemia.     

Delivery of erythropoietin by encapsulated myoblasts in a genetic model of severe anemia

BACKGROUND: Existing animal models of anemia inadequately reflect the hematocrit usually present in chronic renal failure (CRF) patients and do not permit long-term treatment studies. The transgenic mouse strain 134.3LC (Epo-TAg(H)) displays a severe chronic anemia resembling that observed clinically during CRF, while displaying an active, normal life span. This phenotype makes it a particularly interesting mouse model for testing erythropoietin (Epo)-based gene transfer strategies. METHODS: Ex vivo gene therapy was employed to administer mouse Epo to homozygous anemic Epo-TAg(H) mice. Encapsulated C(2)C(12) myoblasts genetically engineered to secrete 163 IU mouse Epo/10(6) cells/day were subcutaneously transplanted on the dorsal flank of the mice. Efficacy of delivered Epo was monitored by weekly measurements of animal hematocrit. RESULTS: Most treated homozygous Epo-TAg(H) mice displayed only a transient rise in hematocrit before eventually decreasing to levels as low as 3%. Administering the immunosuppressor anti-CD4+ monoclonal antibody (mAb) to homozygous Epo-TAg(H) mice, beginning at the time of implantation, permitted a rise in hematocrit that remained stable at elevated levels in cases of continued immunosuppression. CONCLUSIONS: Mice having the T antigen insertion in both Epo alleles appeared to develop an immune response to the natural mouse Epo delivered by encapsulated cells. By preventing this reaction using immunosuppression, we demonstrate that encapsulated myoblasts can deliver therapeutic doses of mouse Epo systemically and restore hemopoiesis in a genetic model of severe anemia.     

Erythropoietin delivery by genetically engineered bone marrow stromal cells for correction of anemia in mice with chronic renal failure

The goal of this research was to develop a strategy to couple stem cell and gene therapy for in vivo delivery of erythropoietin (Epo) for treatment of anemia of ESRD. It was shown previously that autologous bone marrow stromal cells (MSCs) can be genetically engineered to secrete pharmacologic amounts of Epo in normal mice. Therefore, whether anemia in mice with mild to moderate chronic renal failure (CRF) can be improved with Epo gene-modified MSCs (Epo+MSCs) within a subcutaneous implant was examined. A cohort of C57BL/6 mice were rendered anemic by right kidney electrocoagulation and left nephrectomy. In these CRF mice, the hematocrit (Hct) dropped from a prenephrectomy baseline of approximately 55% to 40% after induction of renal failure. MSCs from C57BL/6 donor mice were genetically engineered to secrete murine Epo at a rate of 3 to 4 units of Epo/10(6) cells per 24 h, embedded in a collagen-based matrix, and implanted subcutaneously in anemic CRF mice. It was observed that Hct increased after administration of Epo+MSCs, according to cell dose. Implants of 3 million Epo+MSCs per mouse had no effect on Hct, whereas 10 million led to a supraphysiologic effect. The Hct of CRF mice that received 4.5 or 7.5 million Epo+MSCs rose to a peak 54+/-4.0 or 63+/-5.5%, respectively, at 3 wk after implantation and remained above 48 or 54% for >19 wk. Moreover, mice that had CRF and received Epo+MSCs showed significantly greater swimming exercise capacity. In conclusion, these results demonstrate that subcutaneous implantation of Epo-secreting genetically engineered MSCs can correct anemia that occurs in a murine model of CRF.     

Use of clinical guidelines for treatment of anemia among hemodialysis patients

Changing financial incentives have strongly influenced dosing patterns of recombinant human erythropoietin (rHuEPO) since its introduction in 1989. Although guidelines for prescribing rHuEPO exist, the extent to which they are adhered to is unknown. Using a retrospective cohort observational study design, the factors influencing the initial dosing of rHuEPO prescribed to 413 hemodialysis patients in 1994 were examined. Patient weight, the only recommended guideline, was not found to be a significant predictor of dosing of rHuEPO after controlling for selected patient demographic and clinical characteristics. The strongest predictor for initial rHuEPO dosing was hematocrit followed by White race (p < 0.05). Finally, each subsequent month was associated with a significantly larger initial rHuEPO dose, reflecting the general trend in increasing dose since 1991 (p < 0.001). In conclusion, despite the recent DOQI guidelines for treatment of anemia among persons with chronic renal failure, providers are not using patient weight as an independent criterion for determining dosing of rHuEPO.     

Evidence for renal vasodilation in pre-dialysis patients during correction of anemia by erythropoietin.

Results from animal experiments have suggested that treatment with recombinant human erythropoietin (rHuEPO) causes changes in renal hemodynamics which are detrimental to renal function. Therefore, the effects of correction of the anemia by rHuEPO on glomerular filtration rate (GFR; inulin clearance) and effective renal plasma flow (ERPF; PAH clearance) were studied in eight pre-dialysis patients. The studies were done before (Hct 0.24 +/- 0.05 liter/liter) and at 89 +/- 19 days after the start of rHuEPO therapy (Hct 0.39 +/- 0.03 liter/liter). To further evaluate the effects of ACE inhibition, 25 mg of captopril was given orally after baseline values had been obtained. Baseline GFR, renal blood flow (RBF) and filtration fraction (FF) did not change during rHuEPO therapy. At low hematocrit (Hct) captopril induced a significant increase in ERPF and RBF, and a decrease in MAP. After correction of the hematocrit the blood pressure lowering effect of captopril remained unchanged. However, captopril no longer induced changes in ERPF and RBF. We conclude that the increase in hematocrit had no adverse effects on GFR. The results suggest that changes in hematocrit may influence the effects of ACE inhibition on efferent vascular resistance. Therefore, the hematocrit should be taken into account when evaluating studies on the effects of ACE inhibition in the progression of chronic renal failure.     

Future trends and issues in erythropoietin. Part II.

Although recombinant human erythropoietin (rHuEPO) has only been approved for clinical use since 1989, its beneficial effects in the treatment of anemia in patients with chronic renal failure has been clearly demonstrated. Bolstered by this success, clinical investigators are now turning to other types of anemia that might benefit from such therapy. Part II of this article will continue to discuss some of the potential areas of clinical application for rHuEPO. Part I was published last month in NN&I.     

Short-term efficiency and safety of gene delivery into canine kidneys.

BACKGROUND: Gene delivery of biologically active molecules to the kidney may have potential therapeutic applications in renal and cardiovascular diseases. Recombinant adenovirus is one of the most efficient vectors for in vivo gene delivery. However, in vivo toxicity at the site of administration has to be evaluated for the successful use of adenovirus-mediated gene transfer. The aim of this study was to document precisely the short-term safety of different routes of intra-renal adenoviral administration and to compare their transduction efficiency. METHODS: Dog puppies were injected with an adenoviral vector expressing the beta-galactosidase reporter gene in both kidneys via three different routes, i.e. intra-renal-ureteral route (IU) and intra-renal-arterial route with (IAC) or without (IA) clamping of the renal vein. Toxicity of viral administration was assayed on day 4 at both physiological and histological levels. Renal samples were monitored for the presence of nuclear beta-galactosidase-expressing cells. RESULTS: All renal physiological parameters (glomerular filtration rate, effective renal plasma flow, and electrolyte excretion fractions) remained stable whatever the route of viral administration. No histological lesion was detected in any of the haematoxylin-eosin-stained kidney sections, and there was no evidence of ischaemia-reperfusion injury in the kidneys subjected to venous clamping. Efficient transgene expression was obtained in dog kidneys following IAC and IU injection of adenoviral vectors. Gene transfer via the IAC route induced gene expression predominantly in the cortical interstitial cells. Retrograde IU adenoviral injection resulted in reduced transduction efficiency compared with the IAC route, with transgene expression occurring mainly in the distal tubular and pyelic epithelial cells. CONCLUSIONS: The two major findings of this study were (i) the absence of acute histological and functional renal alteration following intra-arterial and intra-ureteral injections of adenoviral vectors in both kidneys of healthy dogs, and (ii) the efficiency of transgene expression with specific cellular targeting according to the route of administration.     

Factors affecting the response to erythropoiesis-stimulating agents

Recombinant human erythropoietin (rHuEPO) has transformed the management chronic renal failure (CKD) and considerably improved the outcome of patients on regular chronic dialysis. However, a significant number of patients fail to respond to high of Erythropoiesis-stimulating agents (ESAs) and several causes of inadequate response to epoetin therapy have been identified. Some factors, such as gender, age, length of time on dialysis, type of dialysis and co-morbidities such as hemoglobinopathy, are not susceptible to clinical intervention. However, many other factors can be adjusted. Iron deficiency, whether functional or absolute, is the most common factor that limits the response to rHuEPO. Monitoring of iron parameters and a large use of iron supplementation result in an efficient epoetin response. Infection and inflammation have been shown to reduce responsiveness to ESAs by disrupting iron metabolism and increasing the release of pro-inflammatory cytokines that inhibit erythropoiesis. Increase dialysis dose is associated with improvements in anemia correction and reduced requirements for ESAs. Severe hyperparathyroidism and aluminum overload lead to a reduced number of responsive erythroid progenitor cells. Finally, a number of nutritional factors, such as deficiencies of carnitine, vitamin B12, folic acid, and vitamin C, are susceptible to alter erythropoiesis. Optimizing patient response to ESAs therefore requires consideration of many of well-established factors and is important for both patient outcomes and cost of treatment.     

活体转染肝细胞生长因子基因对小鼠急性肝功能衰竭的治疗作用

目的 研究肝细胞生长因子（HGF）基因治疗对小鼠急性肝衰模型的治疗作用。方法 构建人肝细胞生长因子（hHGF）表达载体，利用脂质体介导法在活体内转染肝细胞生长因子基因，利用荧光显微镜检测肝组织内绿色荧光蛋白（GFP）表达了解目的基因的表达，用酶联免疫吸附试验（ELISA）法检测血清中人肝细胞生长因子的含量，通过观察小鼠急性肝衰模型的生存率、肝功能变化、肝组织病理改变来检测肝细胞生长因子基因对急性肝衰的治疗作用，通过检测肝组织中PC—NA指数的变化了解肝脏的增殖能力的变化。结果 荧光显微镜下可见肝组织内有绿色荧光蛋白的表达，转染人肝细胞生长因子基因后在血清中可检测到hHGF的表达，而且可持续1周以上，与对照组相比。转染hHGF基因组的生存率明显提高（40．0％vs11．5％，P〈0．05），血清ALT、TBi明显降低，肝组织中PCNA指数也明显升高。结论 活体转染肝细胞生长因子基因可获得表达，而且肝细胞生长因子基因对急性肝衰小鼠有治疗作用。     

Safety and efficacy of erythropoietin in children with chronic renal failure

 A prospective randomized study of the use of recombinant human erythropoietin (rHuEPO) in children with chronic renal disease was conducted to assess dosing requirements and side effects. Forty-four children with chronic renal failure, aged 4 months to 21 years, were studied. Twenty-five patients were pre dialysis, 10 on peritoneal dialysis, and 9 on hemodialysis. Patients received either 150 U/kg per week or 450 U/kg per week divided thrice weekly of rHuEPO for 12 weeks or until target hemoglobin (Hb) was attained. Dose was then adjusted to maintain a normal Hb. Eighty-two percent of patients reached target Hb by 7.9±5.6 weeks (mean±SD); 95% of patients in the high-dose group and 66% in the low-dose group reached target Hb within 12 weeks. The overall median rHuEPO dose at target Hb was 150 U/kg per week. Hemodialysis patients tended to require more rHuEPO to maintain a normal Hb (median 250 U/kg per week). Transfusion requirements and panel-reactive antibody levels decreased during the 12 weeks. Iron deficiency and/or hypertension occurred in 30% of children. In conclusion, rHuEPO at 150 U/kg per week is safe and effective in treating anemia in children with chronic renal disease. Received: 12 March 1998 / Revised: 24 June 1998 / Accepted: 6 July 1998