Biomedical subjects

Sang-Hoon Lee

Publications and source records attributed to Sang-Hoon Lee.

At least 19 recordsLinked to original sources

PubMed2006

Excess copper induced physiological and proteomic changes in germinating rice seeds.

Copper is an essential micronutrient for plants. Present at a high concentration in soil, copper is also regarded as a major toxicant to plant cells due to its potential inhibitory effects against many physiological and biochemical processes. The interference of germination-related proteins by heavy metals has not been well documented at the proteomic level. In the current study, physiological, biochemical and proteomic changes of germinating rice seeds were investigated under copper stress. Germination rate, shoot elongation, plant biomass, and water content were decreased, whereas accumulation of copper and TBARS content in seeds were increased significantly with increasing copper concentrations from 0.2mM to 1.5mM followed by germination. The SDS-PAGE showed the preliminary changes in the polypeptides patterns under copper stress. Protein profiles analyzed by two-dimensional electrophoresis (2-DE) revealed that 25 protein spots were differentially expressed in copper-treated samples. Among them, 18 protein spots were up-regulated and 7 protein spots were down-regulated. These differentially displayed proteins were identified by MALDI-TOF mass spectrometry. The up-regulation of some antioxidant and stress-related proteins such as glyoxalase I, peroxiredoxin, aldose reductase, and some regulatory proteins such as DnaK-type molecular chaperone, UlpI protease, and receptor-like kinase clearly indicated that excess copper generates oxidative stress that might be disruptive to other important metabolic processes. Moreover, down-regulation of key metabolic enzymes like alpha-amylase or enolase revealed that the inhibition of seed germinations after exposure to excess copper not only affects starvation in water uptake by seeds but also results in failure in the reserve mobilization processes. These results indicate a good correlation between the physiological and biochemical changes in germinating rice seeds exposed to excess copper.

Biomass↗

PubMed2006

Long-term treatment with long-acting risperidone in Korean patients with schizophrenia.

OBJECTIVES: We evaluated the efficacy and safety of long-acting risperidone for 48-week period in Korean patients. METHODS: This was a non-randomized, open-label, single-centered, 48-week study. Each of the participants visited the hospital every 2 weeks, and injections were given at each visit. Complete evaluations were done on five occasions (baseline, 12, 24, 36, 48 weeks). We used Clinical Global Impression, Positive and Negative Syndrome Scale, Global Assessment of Functioning, Subjective Well-being under Neuroleptic treatment scale and Short-form-36 health survey. Drug attitude inventory and Drug Induced Extra-Pyramidal Symptoms Scale were also used. RESULTS: Forty patients were enrolled, and twenty-five patients completed this study. The therapeutic response rate was 36.1% in LOCF and 48% in completer's analysis. Scores on CGI, PANSS subscales and total were significantly decreased over 48-week period. Scores on other assessments did not show any significant changes over the period. At weeks 48, there was no significant difference in the changes of scores from baseline on self-rated assessments between the clinical improvement and non-improvement groups. CONCLUSIONS: Our study showed significant improvement of investigator-rated psychiatric symptoms in long-term follow-up using long-acting risperidone. Further researches would be required to find out the effects of the psychiatric symptom improvements on overall changes in perceived functioning and well-being.

Adult↗

PubMed2006

Risk factors for leg length discrepancy in patients with congenital vascular malformation.

OBJECTIVES: This study was conducted to determine the clinical risk factors for the development of leg length discrepancy (LLD) in patients with congenital vascular malformation (CVM) affecting the lower extremity. METHODS: A retrospective analysis was conducted of a prospectively collected database that included 361 patients who underwent assessment of a CVM lesion from September 1994 to January 2005. We measured LLD using lower extremity scanograms of 229 patients who were suspected of having LLD on physical examination. The risk factor analysis for a clinically significant LLD (>2 cm) was performed with the variables of age, gender, features of CVM (type, extent and depth), and the deep vein status (agenesis, hypoplasia, phlebectasia) of the affected limb. Fisher's exact test and the chi(2) test were used for the univariate analysis, and a logistic regression test was performed for the multivariate analysis. Among the patients with LLD, we compared the overgrowth group and undergrowth group with the Fisher's exact test to identify differences between the two subgroups. RESULTS: The included patients were 153 males (42%) and 208 females (57%) with a mean age of 20 +/- 14 years (range, 1 to 62). There were 157 patients (43%) in the still growing age group (age <15 years) and 204 (57%) were in the finished growing age group (age >15 years). The types of CVMs included 215 venous (60%), 43 arteriovenous (12%), 46 lymphatic (13%), and 57 (16%) combined venolymphatic malformations. On the lower extremity scanogram, 26 patients (7%) had a LLD of >2 cm due to overgrowth (n = 20) or undergrowth (n = 6) of the affected limbs. The univariate analysis showed that a venolymphatic malformation (P = .003) and a whole leg CVM (P = .000) were significant risk factors for development of LLD. However, the multivariate analysis identified the whole leg CVM lesion as a single independent risk factor for LLD (P = .004; odds ratio, 6.512, 95% confidence interval, 1.788 to 23.713). On subgroup analysis, a whole leg CVM was also identified as a risk factor for overgrowth of the affected limb. In a comparison between two subgroups of LLD (overgrowth v. undergrowth), overgrowth was significantly (P = .022) more common in female than in male patients. CONCLUSIONS: As a clinical risk factor for development of LLD, the extent of the CVM lesion was a single independent risk factor regardless of the type or depth of the CVM lesion. In addition, our data suggest that overgrowth or undergrowth of the affected limb, as a cause of LLD, might be related to gender.

Adolescent↗

PubMed2006

Association of the programmed cell death 1 (PDCD1) gene polymorphism with ankylosing spondylitis in the Korean population.

The PD-1 (programmed death 1) molecule is a negative regulator of T cells. PDCD1 (programmed cell death 1) has been reported to have a genetic association in systemic lupus erythematosus and rheumatoid arthritis in Caucasians. However, there are no reports on the association between this gene and ankylosing spondylitis (AS). The present study investigated the association of the PD-1 polymorphisms and the haplotypes with AS in a Korean population sample. In a case-control association study, two single-nucleotide polymorphisms, PD-1.5 C/T and PD-1.9 T/C, were genotyped in 95 AS patients and 130 healthy controls. The T allele of the PD-1.9 polymorphism was more frequent in the Korean male population with AS than in the Korean male controls (21.0% versus 6.9%, odds ratio 1.89, 95% confidence interval 1.483 to 2.408). The frequency of the CT haplotype (PD-1.5 C/T and PD-1.9 T/C) was higher in the AS patients (19%) than the controls (5.4%) (odds ratio 1.83, 95% confidence interval 1.559 to 2.521). The PD-1 polymorphism was demonstrated in Korean AS patients. The results suggest a genetic association between the PD-1 polymorphism and susceptibility to AS.

Adult↗

PubMed2006

The incidence of gastro-esophageal disease for the patients with typical chest pain and a normal coronary angiogram.

BACKGROUND: Although patients may present with typical chest pain and exhibit ischemic changes on the cardiac stress test, they are frequently found to have a normal coronary angiogram. Thus, we wanted to determine which procedures should be performed in order to make an adequate diagnosis of the cause of chest pain. METHODS: 121 patients (males: 42, 34.7%) who had a normal coronary angiogram with typical chest pain were included in this study. All the patients underwent upper endoscopy, Bernstein's test and esophageal manometry. RESULTS: Among the 121 patients, clinically stable angina was noted in 107 (88.4%). Stress testing was done in 82 (67.8%); it was positive in 52 (63.4%). Endoscopic findings were erosive gastritis in 18 (14.8%), gastric ulcer in 4 (3.3%), duodenal ulcer in 5 (4.1%), and reflux esophagitis in 16 (13.2%). Positive results were observed on Berstein's test for 68 patients (56.2%); 59 (86.8%) of them had non-erosive reflux disease. On the esophageal manometry, 35 (28.9%) of these patients had motility disorders. Nutcracker esophagus was observed in 27 patients (22.3%), nonspecific esophageal motility disorder was observed in 5 (4.1%), and hypertensive lower esophageal sphincter was observed in 3 (2.5%). Among the 52 patients with positive cardiac stress testing and a negative coronary angiogram (this clinically corresponded to microvascular angina), 46 patients (85.1%) showed abnormal findings on the gastro-esophageal studies. CONCLUSIONS: In our study, 85.1% of the patients with microvascular angina revealed positive results of gastric or esophageal disease. In spite of any existing evidence of microvascular angina or cardiac syndrome X, it would be more advisable to perform gastro-esophageal studies to adequately manage chest pain.

Adult↗

PubMed2005

Development of a sandwich enzyme-linked immunosorbant assay for the quantification of vitellogeinin in Bullfrog (Rana catesbeiana).

A sandwich enzyme-linked immunosorbant assay (ELISA) was developed to quantitatively detect Bullfrog (Rana catesbeiana) vitellogenin (VTG) levels. This procedure involved a sandwich ELISA using monoclonal antibodies of BVmA1 and BVmA2 against Bullfrog-VTG, and BVmA1 conjugated to horseradish peroxidase as the detection antibody. The assay range was between 9.4 ng/ml and 1200 ng/ml and the recovery of the VTG added to Bullfrog control male serum was 92.0-108.8%. Male Bullfrog was induced by injection 17beta-estradiol (E2) for four weeks and Bullfrog-VTG levels were measured each week. Histological analysis was performed for investigating the correlation of the effect to male reproduction and Bullfrog-VTG level variation depending on E2 dose. After two weeks of E2 exposure, the induced Bullfrog-VTG level was significantly higher than Bullfrog control female (p<0.05). After four weeks of E2 exposure, the rupture and fusion of seminiferous tubule in the testes of male Bullfrog were shown and provided direct evidence that the reproduction of male Bullfrog was affected by estrogenic compounds. Bullfrog-VTG bioassay, using the sandwich ELISA, could be a sensitive and useful tool for quantification of estrogenic principles in aquatic environments.

Animals↗

PubMed2005

The high incidence of meiotic errors increases with decreased sperm count in severe male factor infertilities.

BACKGROUND: The high frequency of aneuploidy sperm raises concerns that there may be an increased incidence of aneuploid offspring in ICSI programmes. In order to assess the role that chromosome complement plays in normal and abnormal fertility, detailed molecular cytogenetic studies must be done on sperm samples from men with normal and abnormal fertility. METHODS: To understand more clearly the cytogenetic make-up of sperm from oligoasthenoteratozoospermic (OAT) patients, multi-colour fluorescence in situ hybridization was used to determine numerical chromosome abnormalities. RESULTS: Increased aneuploidy frequencies for chromosomes 13, 18, 21, X and Y were detected in sperm from OAT patients. The frequencies of diploidy also increased. There were no differences in non-disjunction at meiosis I compared to meiosis II. Sperm count inversely correlated with the frequencies of diploidy, aneuploidies for chromosomes 13 and 21 in OAT patients. Twenty-two cycles of ICSI and 18 embryo transfers were performed in 20 couples. Only three cases achieved successful pregnancies. CONCLUSIONS: A higher incidence of meiotic errors and lower sperm counts was found in sperm from OAT patients.

Adult↗

PubMed2005

Detection and identification of Mycobacterium tuberculosis in joint biopsy specimens by rpoB PCR cloning and sequencing.

Osteoarticular tuberculosis (OAT) is an extrapulmonary tuberculosis and accounts for 1 to 3% of all tuberculosis cases. We used an rpoB PCR-plasmid TA cloning-sequencing method to detect and identify tubercle bacilli in surgical specimens from patients suspected of having OAT. By comparing the similarities of the rpoB sequences determined with those in GenBank, Mycobacterium tuberculosis was detected in 23 of 43 samples. Three of the 23 positive samples had mutations at codon 531, which are commonly observed in rifampin-resistant M. tuberculosis strains. Our results suggest that the rpoB PCR-TA cloning-sequencing method developed, which detects M. tuberculosis and which simultaneously determines its rifampin susceptibility, can also be used efficiently for the diagnosis of OAT.

Antitubercular Agents↗

PubMed2004

Mutational hot spot in the DSPP gene causing dentinogenesis imperfecta type II.

The current system for the classification of hereditary defects of tooth dentin is based upon clinical and radiographic findings and consists of two types of dentin dysplasia (DD) and three types of dentinogenesis imperfecta (DGI). However, whether DGI type III should be considered a distinct phenotype or a variation of DGI type II is debatable. In the 30 years since the classification system was first proposed, significant advances have been made regarding the genetic etiologies of inherited dentin defects. DGI type II is recognized as an autosomal dominant disorder with almost complete penetrance and a low frequency of de novo mutations. We have identified a mutation (c.52G-->T, p.V18F) at the first nucleotide of exon 3 of the DSPP (dentin sialophosphoprotein) gene in a Korean family (de novo) and a Caucasian family. This mutation has previously been reported as causing DGI type II in a Chinese family. These findings suggest that this mutation site represents a mutational "hot spot" in the DSPP gene. The clinical and radiographic features of these two families include the classic phenotypes associated with both DGI type II and type III. Finding that a single mutation causes both phenotypic patterns strongly supports the conclusion that DGI type II and DGI type III are not separate diseases but rather the phenotypic variation of a single disease. We propose a modification of the current classification system such that the designation "hereditary opalescent dentin" or "DGI type II" should be used to describe both the DGI type II and type III phenotypes.

Child, Preschool↗

PubMed2004

Effects of the controlled-released TGF-beta 1 from chitosan microspheres on chondrocytes cultured in a collagen/chitosan/glycosaminoglycan scaffold.

The objectives of this study were (1) to develop a three-dimensional collagen/chitosan/glycosaminoglycan (GAG) scaffold in combination with transforming growth factor-beta1 (TGF-beta 1)-loaded chitosan microspheres, and (2) to evaluate the effect of released TGF-beta 1 on the chondrogenic potential of rabbit chondrocytes in such scaffolds. TGF-beta 1 was loaded into chitosan microspheres using an emulsion-crosslinking method. The controlled release of TGF-beta 1, as measured by enzyme-linked immunosorbent assay (ELISA), was monitored for 7 days. The porous scaffolds containing collagen and chitosan were fabricated by using a freeze drying technique and crosslinked using 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide (EDC) in the presence of chondroitin sulfate (CS), as a GAG component. The TGF-beta 1 microspheres were encapsulated into the scaffold at a concentration of 10 ng TGF-beta 1/scaffold and then chondrocytes were seeded in the scaffold and incubated in vitro for 3 weeks. Both proliferation rate and glycosaminoglycan (GAG) production were significantly higher in the TGF-beta 1 microsphere-incorporated scaffolds than in the control scaffolds without microspheres. Extracellular matrix staining by Safranin O and immunohistochemistry for type II collagen were elevated in the scaffold with TGF-beta 1 microspheres. These results suggest that TGF-beta 1 microspheres when incorporated into a scaffold have the potential to enhance cartilage formation.

Animals↗

PubMed2004

Enhancing effect of taurine on glucose response in UCP2-overexpressing beta cells.

Uncoupling protein 2 (UCP2) is up-regulated in pancreatic beta cells when exposed to long-term high glucose or free fatty acids, which results in impaired glucose-induced insulin secretion (GIIS). We have evaluated whether taurine pretreatment can restore impaired GIIS of beta cells overexpressing UCP2 by adenovirus (Ad)-mediated transfection technique. In Ad-Null control cells, externally applied glucose (10 mM) inhibited ATP-sensitive potassium (K(ATP)) channel activity even in the presence of 300 microM diazoxide. In Ad-UCP2 cells, however, glucose failed to inhibit K(ATP) channel activity; despite the response of K(ATP) channel itself to glibenclamide was normal. The glucose-stimulated increase of cytosolic Ca2+ concentration ([Ca2+]c) and insulin secretion was also diminished (P < 0.05). When taurine (3 mM) was pretreated for 24 h, the glucose responses of Ad-UCP2 cells were remarkably restored. The effect of taurine was, however, blocked by CCCP (carbonyl cyanide p-chlorophenylhydrazone; 2 microM), a mitochondrial Ca2+ uniporter inhibitor. These results suggest that taurine restores impaired GIIS in Ad-UCP2 cells, at least partially, by acting on the mechanism for Ca2+ sequestration into the mitochondrial matrix.

ATP-Binding Cassette Transporters↗

PubMed2004

Effects of a chitosan scaffold containing TGF-beta1 encapsulated chitosan microspheres on in vitro chondrocyte culture.

The objectives of this study were (1) to develop a three-dimensional chitosan scaffold in combination with transforming growth factor-beta1 (TGF-beta1)-loaded chitosan microspheres and (2) to evaluate the effect of the TGF-beta1 release on the chondrogenic potential of rabbit chondrocytes in the scaffolds. TGF-beta1 was loaded into chitosan microspheres using an emulsion-crosslinking method, resulting in spherical shapes with a size ranging from 0.3 to 1.5 microm. Controlled release of TGF-beta1, as measured by enzyme-linked immunosorbent assay (ELISA), was observed with chitosan microspheres over 7 days. Chitosan solutions (2% and 3%) were fabricated into two types of scaffolds with different pore morphologies and mechanical properties using a freeze-drying technique, with the result that scaffold with higher concentrations showed smaller pores and lower porosity, leading to a much stronger scaffold. The TGF-beta1 microspheres were incorporated into the scaffolds at a concentration of 10 ng TGF-beta1/scaffold and then chondrocytes seeded into each scaffold and incubated in vitro for 2 weeks. The 2% chitosan scaffolds showed higher cell attachment levels than the 3% chitosan scaffolds (P < 0.01), regardless of the TGF-beta1 microspheres. Both the proliferation rate and glycosaminoglycan (GAG) production were significantly higher for scaffolds incorporating TGF-beta1 microspheres than for the control scaffolds without microspheres 10 days after incubation. Extracellular matrix staining by Safranin O and immunohistochemistry for type II collagen both significantly increased in scaffolds containing TGF-beta1 microspheres. These results suggest that the TGF-beta1 microsphere incorporated in scaffolds have the potential to enhance cartilage formation.

Animals↗

PubMed2004

Anti-inflammatory effect of bee venom on type II collagen-induced arthritis.

Bee venom (BV) has been used to relieve pain and reduce inflammation in traditional Oriental medicine, especially in chronic inflammatory diseases such as rheumatoid arthritis (RA). We previously reported that the BV injection into a traditional acupuncture point (Zusanli) reduced arthritis-associated edema and nociceptive responses in Freund's adjuvant-induced arthritis in rats (Kwon et al., 2001). This study was designed to evaluate the anti-inflammatory and anti-cytokine effect of BV on a murine type-II collagen-induced arthritis (CIA) model. Male mice were immunized by spontaneous injection of 100 microg of an emulsion of bovine type-II collagen and complete Freund's adjuvant (CFA), with a booster injection after 2 weeks. In the experimental group, 0.1 ml BV was injected at acupuncture point (Zusanli) near both knees twice a week for a total of 5 times. In the control group, normal saline was injected at the same frequencies. These injections began 5 weeks after the first collagen injection. Starting the 3rd week after the first collagen injection, we examined limb swelling and severity of arthritis twice a week. At 8 weeks, mice were sacrificed and synovial tissue was examined with the light microscope and serum cytokines (IL-1beta and TNF-alpha) were measured by ELISA. The incidence of arthritis, the mean arthritis index and the number of arthritic limbs were significantly lower in the treatment compared to the control group (63% versus 75%, 3.4% versus 8.5%, 23% versus 75%, respectively). Among the serum proinflammatory cytokines, the production of TNF-alpha in the BV group was suppressed compared to the control group (59 +/- 4.5 versus 99.5 +/- 6.5, p < 0.05), but IL-1beta was not suppressed. The examination of the histopathology of the joints of murine CIA showed decreased inflammation signs and less lymphocyte infiltration after BV acupuncture therapy. Acupuncture therapy with BV suppressed the development of arthritis and caused inhibition of the immune responses in type-II collagen-induced arthritis.

Acupuncture Points↗

PubMed2004

Analysis of passive mixing behavior in a poly(dimethylsiloxane) microfluidic channel using confocal fluorescence and Raman microscopy.

Confocal fluorescence microscopy (CFM) and confocal Raman microscopy (CRM) have been applied to monitor the laminar flow mixing behavior in a poly(dimethylsiloxane) (PDMS) microfluidic channel. Two passive PDMS micromixing devices were fabricated for this purpose: a two-dimensional round-wave channel and a three-dimensional serpentine channel. The microscale laminar flow mixing of ethanol and isopropanol was evaluated using the CFM and CRM at various flow rates. The mixing behavior of confluent streams in the microchannel was assessed by determining the degree of color change in Rhodamine 6G dye on mixing using the CFM. However, it was also possible to quantitatively evaluate the mixing process without employing a fluorescence label using the CRM. The results show a strong potential for CRM as a highly sensitive detection tool to measure fundamental fluid mixing processes and to provide detailed information on chemical changes of non-fluorescent reaction mixtures in a PDMS microfluidic channel.

2-Propanol↗

PubMed2003

Comparative analysis of effects of cytokine gene adjuvants on DNA vaccination against Mycobacterium tuberculosis heat shock protein 65.

DNA-based vaccines generate potent cellular immunity as well as humoral immunity. It seems evident that cytokines play a crucial role in generation of effector T cell subsets and in determining the magnitude of the response by DNA vaccines. In this study, we compared the effects of several TH1 cytokine genes as adjuvant in DNA vaccination using mycobacterial Hsp65 as a model antigen. Our results demonstrated that although the overall immune response to Hsp65 was enhanced by co-injection of Hsp65 DNA with cytokine genes, each cytokine gene was shown to affect different immune response elements. Co-injection of Hsp65 DNA with IL-12 or GM-CSF led to an increase in IFN-gamma production and represented potent protections against Mycobacterium tuberculosis challenge, while that with Eta-1, IL-12 or IL-18 gene led to an elevated IgG2a/IgG1 ratio. Interestingly, co-administration of Flt3L gene was shown to enhance the Ag-specific CTL response. These results show that the direction and magnitude of immune response in DNA vaccination against Hsp65 of M. tuberculosis could be modulated in different ways by co-injection of an appropriate cytokine gene as adjuvant.

Adjuvants, Immunologic↗

PubMed2003

Pharmacokinetic modeling of phagocytic activity of the liver using superparamagnetic iron oxide nanoparticles in dynamic MR imaging.

The purpose of this study was to determine whether phagocytic activity is measurable by dynamic superparamagnetic iron oxide-enhanced MR imaging. For these experiments on New Zealand White rabbits, which were randomly allocated to normal and silica treated groups, we performed a dynamic MR study and radioisotope study with Tc99m-phytate. In this dynamic MR study, the ratio (Rv) of the distribution volumes of iron oxide (Vm/Ve) could be obtained by applying three- compartment model to the data obtained from the kidney and liver simultaneously. Changes in Rv caused by silica injection and by dosing superparamagnetic iron oxide, AMI-25, were evaluated. In the dynamic MR study using a Beagle dog model the input function could be calculated from data obtained from the hepatic artery and portal vein. Rv's reached maximum values at around 80 minutes after the AMI-25 injection. The Rv of the normal group was 5.06 +/- 1.53 whereas the Rv of the silica treated group was 2.13 +/- 1.20. The results were similar to tissue count data obtained by radioisope study. The Rv value was not dependent on the injected dose of AMI-25. The rate of transport constants (k1, k2, k3) could not be estimated using the 3 compartment model regardless of obtaining the input function. We conclude that Rv may be an quantitative index of decreased phagocytic activity in the liver as determined by dynamic superparamagnetic iron oxide- enhanced MRI.

Animals↗

PubMed2003

Posterolateral reconstruction using split Achilles tendon allograft.

Injury to the cruciate ligaments of the knee commonly occurs in association with posterolateral instability, which can cause severe functional disability including varus, posterior translation, and external rotational instability. Failure to diagnose and treat an injury of the posterolateral corner in a patient who has a tear of the cruciate ligament can also result in the failure of the reconstructed cruciate ligament. Unlike isolated posterior cruciate ligament injury, there seems to be a consensus of opinion that injury to the posterolateral corner, whether isolated or combined, is best treated by reconstructing the posterolateral corner along with the coexisting cruciate ligament injury, if combined. Commonly proposed methods of reconstructing the posterolateral corner have focused on the reconstruction of the popliteus, the popliteofibular ligament, and the lateral collateral ligament. We introduce a new technique for reconstructing the posterolateral corner using a split Achilles tendon allograft. Our method reasonably addresses the several pitfalls in the reconstruction of the posterolateral corner, including (1) concurrent reconstruction of important posterolateral structures, (2) regaining the isometry of the lateral collateral ligament, (3) repositioning the reconstructed popliteus into its original position, and (4) providing a secure fixation method.

Achilles Tendon↗

PubMed2003

Minimal effective dosage of recombinant human erythropoietin in spinal surgery.

Preoperative autologous blood donation is one of the most widely used methods of autotransfusion. However securing a predetermined amount of blood (3 units of whole blood) may be difficult in patients with a low preoperative hematocrit. To determine the minimum effective pretreatment dosage of recombinant human erythropoietin required to secure an adequate amount of preoperative blood for autologous transfusion during posterior decompression and instrumentation fusion using the pedicle screw-rod system in the lumbar spine, a prospective randomized clinical trial was done. Forty-five patients who had a preoperative hematocrit less than 40% were selected and were divided blindly into three groups. Fifty units per kilogram of recombinant human erythropoietin seems to be the minimal effective dosage for securing an adequate amount of preoperative autologous blood donation.

Adult↗