Three-Dimensional Computed Tomography Image Reformation for Comparison of Foraminal Cross-Sectional Dimension in Patients Who Have Undergone Laminoplasty and Laminectomy with Fusion.

PURPOSE OF THE STUDY: Laminectomy with fusion (LF) is commonly performed with laminoplasty (LP) for cervical myelopathy. Foraminal stenosis is important in the surgical treatment of cervical myelopathy. LF and LP can affect foraminal size in different ways. This study aimed to compare foraminal dimensions after LF and LP using a medical computer-assisted design (CAD) program. MATERIAL AND METHODS: Computed tomography (CT) scans of the cervical vertebrae of 16 patients with cervical myelopathy were retrospectively viewed in the Digital Imaging and Communications in Medicine format on a CAD program. CT images were reformatted in an oblique plane perpendicular to the long axis of each foramen from C2-C3 to C6-C7. The narrowest foraminal crosssectional dimension (FCD) was measured and compared between the LF and LP groups at the operated, non-operated, and C4-C5 levels. The difference between the preoperative and postoperative FCDs was also calculated and compared between the operated and C4-C5 levels. Intra- and interobserver reliabilities for FCD measurements were evaluated using intraclass correlation coefficients. RESULTS AND DISCUSSION: At the operated spinal levels, the LF and LP groups showed decreased and increased mean FCDs, respectively. At the adjacent non-operated levels, the mean FCD slightly increased in both the groups. In the LF group, the difference between the preoperative and postoperative FCDs in the C4-C5 levels was larger than that in the other operated levels, but this difference was insignificant. CONCLUSIONS: LF and LP showed contrary results for FCD. Therefore, FCD and kyphosis should be considered for LF and LP. KEY WORDS: three-dimensional, foraminal cross-sectional dimension, laminoplasty, laminectomy fusion, computer-aided design, drafting system, preoperative-postoperative comparison.

Extracellular production of functional single-chain variable fragment against aflatoxin B1 using Escherichia coli.

scFv-BM3 is a single-chain variable fragment (scFv) against aflatoxin B1 (AFB1 ) engineered by affinity maturation and site-directed mutagenesis, and thus has a 31-fold higher affinity than its wild-type. To apply scFv-BM3 to immunological detection of AFB1 , periplasmic expression in Escherichia coli was attempted to produce a functional form of scFv-BM3. scFv-BM3 accumulated as inactive aggregates in the cells. However, it was found that scFv-BM3 secreted into the culture medium had binding activity to AFB1 . Expression conditions for scFv-BM3 were further manipulated to enhance secretion into the culture medium. This extracellular secretion of functional scFv-BM3 was significantly improved by supplementation with Triton X-100 and optimization of expression conditions. The scFv-BM3 purified from the culture medium exhibited a typical antiparallel ß-sheet structure and adopted a proper conformation to bind AFB1 with high affinity and specificity in various biophysical and biochemical analyses. SIGNIFICANCE AND IMPACT OF THE STUDY: Single-chain variable fragments (scFvs) are recombinant antibodies that are difficult to produce as a functional form in Escherichia coli. This study demonstrates the production of functional scFvs against aflatoxin B1 (AFB1 ) (scFv-BM3) using Escherichia coli by extracellular secretion. While periplasmic expression of scFv-BM3 resulted in formation of inactive aggregates in E. coli, the scFv-BM3 secreted into the culture medium adopted a properly folded structure for specific binding to AFB1 . This study promotes the application of functional scFv-BM3 to the immunological detection of AFB1 in biotechnology fields.

Transfibular ankle arthrodesis using burring, curettage, multiple drilling, and fixation with two retrograde screws through a single lateral incision.

PURPOSE: To review the outcome of 23 ankle arthrodeses using burring, curettage, multiple drilling, and fixation with 2 retrograde screws through a single lateral incision. METHODS: Records of 22 consecutive patients aged 39 to 79 (mean, 62.4) years who underwent 23 ankle arthrodeses for end-stage ankle arthritis were reviewed. Through a single lateral incision, articular cartilage was removed using burring and curettage, and multiple holes were drilled using a Kirschner wire, followed by fixation with 2 retrograde screws. The resected distal fibula was fixed to the distal part of the talus and tibia. The position of the ankle and subtalar joint arthrosis was assessed by 2 orthopaedic specialists. Pre- and post-operative American Orthopaedic Foot and Ankle Society (AOFAS) scores were evaluated. RESULTS: The mean operating time was 122 minutes. The mean follow-up period was 41 months. The mean postoperative ankle alignment was suboptimal: 2.7º varus, 6.7º plantar flexion, and 2.9º internal rotation. The mean AOFAS score improved from 30 to 71 (p<0.01). The postoperative varus ankle alignment was not associated with the AOFAS score (r= -0.13, p=0.569). Of the 23 cases, one was nonunion and 22 achieved bone union after a mean of 5.4 (range, 2-16) months; 3 of them were delayed union. Despite bone union, 7 patients complained of persistent pain; 4 of them had progressive arthrosis of the adjacent subtalar joints (n=2) or subtalar and talonavicular joints (n=2). CONCLUSION: Ankle arthrodesis using burring, curettage, multiple drilling, and fixation with 2 retrograde screws achieved a high union rate and acceptable functional score without serious complications.

Arthroscopically assisted percutaneous fixation for trans-scaphoid perilunate fracture dislocation.

Trans-scaphoid perilunate fracture dislocation is a complex carpal dislocation causing marked disruption of the carpal structures. Open treatment has been accepted as standard for this injury. We have used arthroscopically assisted percutaneous screw fixation and bone grafting to treat this injury in four patients. The functional outcome was good. All patients achieved solid union without nonunion or malunion. The complication and morbidity was relatively low; all patients had proper alignment and there was no evidence of instability or avascular necrosis or midcarpal arthritis.

Limb lengthening with a submuscular locking plate.

Ten patients, who were unsuitable for limb lengthening over an intramedullary nail, underwent lengthening with a submuscular locking plate. Their mean age at operation was 18.5 years (11 to 40). After fixing a locking plate submuscularly on the proximal segment, an external fixator was applied to lengthen the bone after corticotomy. Lengthening was at 1 mm/day and on reaching the target length, three or four screws were placed in the plate in the distal segment and the external fixator was removed. All patients achieved the pre-operative target length at a mean of 4.0 cm (3.2 to 5.5). The mean duration of external fixation was 61.6 days (45 to 113) and the mean external fixation index was 15.1 days/cm (13.2 to 20.5), which was less than one-third of the mean healing index (48 days/cm (41.3 to 55). There were only minor complications. Lengthening with a submuscular locking plate can successfully permit early removal of the fixator with fewer complications and is a useful alternative in children or when nailing is difficult.

Discrepancy of interleukin-6 levels between end-stage renal disease patients and patients with acute-phase response with increased lipoprotein(a) concentrations.

Though the concentration of serum lipoprotein(a) [Lp(a)] is mostly determined by genetic factors, secondary factors such as acute-phase response (APR) and end-stage renal disease (ESRD) also contribute to its increase. Lp(a) is known to be one of the acute-phase reactants and interleukin-6 (IL-6) is the key cytokine in the hepatic synthesis of acute-phase proteins. The serum concentrations of Lp(a) and IL-6 were measured in patients with APR and in patients with ESRD to investigate the relationship between Lp(a) and IL-6. A total of 180 patients were selected for the study: 60 patients were normal controls, 60 were patients with renal disease who had been on hemodialysis for more than 6 months [C-reactive protein (CRP)<4.0 mg/L], and 60 were APR patients who had a erythrocyte sedimentation rate (ESR) of over 50 mm/h. The three groups were age- and sex matched. The serum concentrations of Lp(a) and IL-6 were measured by ELISA. The serum concentrations of Lp(a) [median (interquartile range)] in normal controls, ESRD patients, and APR patients were 0.222 (0.103-0.364) g/L, 0.511 (0.308-0.755) g/L, and 0.546 (0.234-0.747) g/L, respectively; those of IL-6 were 1.0 (0.7-1.3) pg/mL, 2.1 (1.4-3.3) pg/mL, and 26.2 (15.2-35.6) pg/mL. The concentration of IL-6, which increases Lp(a) synthesis, was much lower in ESRD patients than in APR patients (p<0.001). However, there were no significant differences in Lp(a) concentration between the two groups (p=0.88). In APR patients, the increase in Lp(a) synthesis seems to play a significant role in the increase in blood Lp(a), but there might be different mechanisms that regulate the increment of serum Lp(a) concentrations in ESRD patients other than synthesis of Lp(a).

Genetic variations of the paraoxonase gene in patients with coronary artery disease.

OBJECTIVES: Paraoxonase (PON) plays an important role in preventing low density lipoprotein (LDL) oxidation and thus may be involved in protection against atherosclerosis. Several studies have suggested that genetic variations of the PON gene are associated with plasma HDL levels and coronary artery disease (CAD). This study was conducted to elucidate the association between three polymorphisms of the PON1 and PON2 genes and Korean patients with CAD. DESIGN AND METHODS: One hundred ninety-one patients with CAD and 113 age-matched normal controls were examined by polymerase chain reaction (PCR). The PCR products were analyzed for PON polymorphisms by restriction enzyme digestion. RESULTS: There was linkage disequilibria between each polymorphism pair in the CAD and control groups. The Hsp92II polymorphism at codon 54 of the PON1 gene was positively associated with HDL-cholesterol levels in the control group (p = 0.02). An association between the AlwI polymorphism and HDL-cholesterol level appeared statistically significant in women of the normal group (p = 0.04). In addition, the DdeI and AlwI polymorphisms were positively associated with HDL (p = 0.02) and LDL (p = 0.03) levels in men of the CAD group, respectively. CONCLUSIONS: Our study suggested a gene-gene interaction between the PON1 and PON2 polymorphisms for CAD risk. However, we could not exclude the possibility that these polymorphisms may have linkage disequilibrium with a tightly linked PON3 locus or significant atherosclerotic alleles of nearby genes. Family studies may, therefore, help to confirm the role of the PON polymorphism for CAD risk.

Apolipoprotein E polymorphism and serum lipoprotein(a) concentrations in a Korean male population.

The purpose of this study was to investigate the effect of apolipoprotein E polymorphism on lipoprotein(a) metabolism by comparing serum lipoprotein(a) concentration with apolipoprotein E genotype in a Korean male population whose high molecular weight (HMW) lipoprotein(a) frequency was 95-98%. Serum lipoprotein(a), total cholesterol, triglyceride and high-density lipoprotein-cholesterol concentrations were measured and the apolipoprotein E genotype determined in 1189 healthy Korean males. The medians of serum lipoprotein(a) concentration in the apo E 2/3 group (0.105 g/L) and the apo E 3/4 group (0-116 g/L) were significantly lower than that in the apo E 3/3 group (0.155 g/L; P < 0.001). The medians of serum triglyceride were 1.497 mmol/L in the apo E 2/3 group, 1.356 mmol/L in the apo E 3/4 group, and 1.452 mmol/L in the apo E 3/3 group (P<0.05). With the significant difference in the serum lipoprotein(a) concentration in Korean males according to apolipoprotein E genotype, and with the negative correlation between serum triglyceride concentration and serum lipoprotein(a) concentration, it is suggested that apolipoprotein E polymorphism and serum triglyceride participate in the metabolism of lipoprotein(a) with HMW.

Effects of hormonal replacement therapy on lipid and haemostatic factors in post-menopausal ESRD patients.

BACKGROUND: Hormone replacement therapy (HRT) has been known to have beneficial effects on various atherosclerotic parameters in the general population of post-menopausal women. To evaluate the effects of HRT on those factors in end-stage renal disease (ESRD) patients, we evaluated the changes of lipid profile, coagulation and fibrinolysis markers, and plasma homocysteine levels after treatment. METHODS: Sixty-five post-menopausal women on maintenance haemodialysis were randomly assigned to either an HRT group (n=33) or a control group (n=32). Median age (range) and duration of haemodialysis (range) were 57 years (40-73) and 42 months (6-150) in the HRT group and 61 years (44-78) and 54 months (8-174) in the control group respectively. Oral conjugated oestrogen (0.625 mg) combined with medroxyprogesterone acetate (2.5 mg) was given daily for 12 weeks to the HRT group. Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), lipoprotein (a) (Lp(a)), fibrinogen, plasminogen activator type 1 antigen (PAI-1), tissue plasminogen antigen (t-PA), von Willebrand factor (vWF), and plasma total homocysteine (tHcy) were measured before and 12 weeks after the start of the study in both groups. RESULTS: There was no difference in baseline values between the control and HRT groups. At 12 weeks, HRT increased HDL-C by 12% (P:<0.01) and TG by 20% (P:<0. 01). HRT decreased LDL-C by 9% (P:<0.01), and Lp(a) by 36% (P:<0.01). PAI-1 and t-PA concentrations were also reduced by 21% (P:<0.01) and 9% (P:<0.05) respectively. The mean values of TC, fibrinogen, vWF, and tHcy levels did not change significantly after HRT. CONCLUSIONS: The above results suggest that HRT has favourable effects on atherosclerosis risk parameters in post-menopausal women with ESRD as in the general population of post-menopausal women.

Atherothrombotic middle cerebral artery territory infarction: topographic diversity with common occurrence of concomitant small cortical and subcortical infarcts.

BACKGROUND AND PURPOSE: MRI has superior capabilities for the detection of cerebral infarcts compared with CT. CT was used to locate infarcts in most previous studies of atherothrombotic middle cerebral artery (MCA) territory infarcts. Thus, there was a possibility of missing concomitant small infarcts. More accurate identification of topographic lesions in MCA territory with MRI may help to establish the pathogenesis of stroke. The present study determines topographic patterns, distribution of vascular lesions, and probable mechanisms. METHODS: Forty-two patients with MCA territory infarcts on routine MRI and no major cause of cardioembolism were studied with conventional angiography or MR angiography. RESULTS: The topographic patterns seen on MRI were subdivided into 4 groups: cortical border-zone infarcts (n=6), pial territory infarcts without insular infarct (n=3), pial territory infarcts with insular infarct (n=14), and large subcortical infarcts (n=19). Of 6 patients with cortical border-zone infarcts, 4 had concomitant small cortical or subcortical multiple lesions. Angiography showed intrinsic MCA disease in 4 patients. Of 3 patients with pial territory infarcts without insular infarct, 2 also had small multiple centrum ovale lesions. All had intrinsic MCA disease. Pial territory infarcts with partial or whole insular lesions were present in 10 and 4 patients, respectively. Five patients had additional multiple cortical or subcortical lesions. Ten patients had intrinsic MCA disease. Of the 19 patients with large subcortical infarcts, 12 had centrum ovale infarcts, and 4 had both basal ganglia and centrum ovale lesions. Ten had concomitant small cortical or subcortical lesions. Six patients had intrinsic MCA disease. CONCLUSIONS: Similar vascular lesions induce different topographic patterns in MCA territory infarction, which are related to individual vascular variability, degree of primary and secondary collateralization, and pathogenesis of infarcts. Our study indicates that concomitant small cortical or subcortical lesions are also commonly associated findings in diverse patterns of MCA territory infarction, which can mostly be explained by probable embolic mechanism.

In vivo antioxidant effect of green tea.

OBJECTIVE: The object of this study was to investigate the in vivo antioxidant effect of green tea and dosage effect of green tea on antioxidant effect. DESIGN: We tested 10 healthy subjects (aged 23-25 y, five women and five men) with overnight fasting. The total antioxidant capacity of plasma was measured at baseline and 60 min and 120 min after ingestion of 150 ml green tea. Green tea was prepared by infusing 2.5 g of dried green tea leaves for 2 min at 80 degrees C in 150 ml of water. In the second week, they took 300 ml of tea (5.0 g of green tea leaves) and, in the third week, 450 ml of tea (7.5 g of green tea leaves). The total antioxidant capacities of plasma were determined with a Total Antioxidant Kit (Randox Laboratories Ltd, UK) using a Cobas Mira analyser (Roche Diagnostic Systems Inc., Switzerland). The mean intra-assay coefficient of variation was 1.2%. RESULTS: The total antioxidant capacity of plasma increased by 1.1% at 60 min and 2.1% at 120 min over baseline value in subjects consuming 150 ml of green tea, which was statistically not significant. However, total antioxidant capacity of plasma after consuming 300 ml of green tea showed a significant increase of 7.0% after 60 min and 6.2% after 120 min (P<0.0001), and after consuming 450 ml 12.0% after 60 min and 12.7% after 120 min over baseline value (P<0.0001). CONCLUSIONS: Total antioxidant capacity of plasma was significantly increased after taking green tea in amounts of 300 and 450 ml. A positive increment according to green tea dosage was also observed. SPONSORSHIP: This work was funded by the Pacific Corporation (Korea).

Reduced oxidative stress in hypoalbuminemic CAPD patients.

OBJECTIVE: Albumin is one of the plasma antioxidants. The higher incidence of cardiovascular disease in dialysis patients with hypoalbuminemia may be related to decreased antioxidant capacity resulting from low serum albumin. We evaluated malondialdehyde (MDA), a marker of oxidative stress, and total antioxidant capacity (TAC) in relation to serum albumin in continuous ambulatory peritoneal dialysis (CAPD) patients. PATIENTS AND METHODS: In this cross-sectional study, we measured MDA, TAC, albumin, uric acid (another important plasma antioxidant), prealbumin, and C-reactive protein (CRP) in the blood of 66 CAPD patients and 30 normal controls.Twenty-two CAPD patients with albumin less than or equal to 3.5 g/dL were divided into two groups: In the experimental group (n = 11), MDA,TAC, and CRP were measured before and after repeated infusion of 20% albumin 100 mL daily for 7 days. In the control group (n = 11), the same parameters were measured without albumin infusion. RESULTS: CAPD patients had lower albumin and higher MDA,TAC, and uric acid than normal controls. There were positive correlations between albumin and TAC or uric acid in CAPD patients. Contrary to our expectation, there was also positive correlation between albumin and MDA in CAPD patients (r = 0.37, p = 0.004). MDA showed a positive correlation with TAC. Uric acid was correlated with TAC. It did not, however, show correlation with MDA. Log CRP was negatively correlated with albumin, but did not show correlation with MDA or TAC. Prealbumin was correlated with MDA, TAC, albumin, and uric acid. Serum albumin in the experimental group increased from 2.5+/-0.3 g/dL to 3.6+/-0.2 g/dL (p < 0.001) at the end of repeated infusions. No changes were seen in MDA, TAC, and CRP in either group. CONCLUSIONS: The present study suggests that lipid peroxidation is increased in CAPD patients and that this is not due to weakening of antioxidant defenses of plasma. Increased TAC was mainly caused by a higher level of uric acid. Reduced, rather than increased, MDA in hypoalbuminemic patients and lack of effects of albumin infusion on levels of MDA suggest that the frequent occurrence of cardiovascular disease in dialysis patients with hypoalbuminemia is not due to the decrease in antioxidant capacity resulting from low serum albumin.

Distribution of haptoglobin phenotypes in a Korean population, using the semi-automated PhastSystem.

We have established a new phenotyping method for haptoglobin, based on sodium dodecyl sulphate-polyacrylamide gel electrophoresis using the PhastSystem (Pharmacia Biotech, Uppsala, Sweden), followed by immunoblotting for detection. We measured haptoglobin concentrations and determined the haptoglobin phenotypes of 316 healthy Koreans using this method: 31 (9.8%) were of Hp 1-1 type, 140 (44.3%) of Hp 2-1 type and 145 (45.9%) of Hp 2-2 type. The haptoglobin allele frequencies were calculated to be 0.32 for Hp1 and 0.68 for Hp2. We were able to visualize up to 12 bands from the human Hp 2-2 polymeric series, with molecular weights in the range 171.9 x 10(3) to 802.2 x 10(3). The reference range of serum haptoglobin concentrations obtained by the IFCC (International Federation of Clinical Chemistry) standard method was 0.27-2.14 g/L. The serum haptoglobin concentration in Koreans was similar to that of Caucasians, but the Hp1 allele frequency was lower in Koreans. Our method could be used in clinical laboratories as a simple and practical method of haptoglobin phenotyping. In addition, the Hp 2-2 polymeric series could be used as high molecular weight standards.

Atherothrombotic cerebellar infarction: vascular lesion-MRI correlation of 31 cases.

BACKGROUND AND PURPOSE: Correlation of MRI findings with atherosclerotic vascular lesions has rarely been attempted in patients with cerebellar infarction. The aim of this study was to correlate the MRI lesions with the vascular lesions seen on conventional cerebral angiography in cerebellar infarction. METHODS: The subjects included 31 patients with cerebellar infarcts who underwent both MRI and conventional cerebral angiography. We analyzed the risk factors, clinical findings, imaging study, and angiography results. We attempted to correlate MRI lesions with the vascular lesions shown in the angiograms. RESULTS: The vascular lesions seen on angiograms were subdivided into 3 groups: large-artery disease (n=22), in situ branch artery disease (n=6), and no angiographic disease with hypertension (n=3). The proximal segment (V1) lesions of vertebral artery were the most common angiographic features in patients with large-artery disease in which stroke most commonly involved the posterior inferior cerebellar artery (PICA) cerebellum. The V1 lesions with coexistent occlusive lesions of the intracranial vertebral and basilar arteries were correlated with cerebellar infarcts, which had no predilection for certain cerebellar territory. The intracranial occlusive disease without V1 lesion was usually correlated with small cerebellar lesions in PICA and superior cerebellar artery (SCA) cerebellum. The subclavian artery or brachiocephalic trunk lesion was associated with small cerebellar infarcts. The in situ branch artery disease was correlated with the PICA cerebellum lesions, which were territorial or nonterritorial infarct. No angiographic disease with hypertension was associated with small-sized cerebellar infarcts within the SCA, anterior inferior cerebellar artery, or SCA cerebellum. CONCLUSIONS: Our study indicates that the topographic heterogeneity of cerebellar infarcts are correlated with diverse angiographic findings. The result that large-artery disease, in which nonterritorial infarcts are more common than territorial infarcts, is more prevalent than in situ branch artery disease or small-artery disease, suggest that even a small cerebellar infarct can be a clue to the presence of large-artery disease.

No relationship between serum lipoprotein(a) and albumin concentrations in patients with acute phase response.

The aim of this study was to investigate the relationship between lipoprotein(a) [Lp(a)] and albumin concentrations in the serum of patients with acute phase response (APR). We have compared the Lp(a) concentrations and apolipoprotein [apo(a)] phenotypes of 40 controls with those of 40 APR patients with normoalbuminaemia and 40 APR patients with hypoalbuminaemia. We have also compared concentrations of haptoglobin (Hp) and alpha 1-antitrypsin (AAT) containing a high sialic acid content, similar to Lp(a). The mean serum Lp(a) concentration (SD) of the 40 controls was 0.190 (0.142) g/L. The mean serum Lp(a) concentration was 0.358 (0.257) g/L (P < 0.001) in 80 APR patients. However, there was no difference in serum Lp(a) concentrations between the APR patients with hypoalbuminaemia [0.353 (0.268) g/L] and the APR patients with normoalbuminaemia [0.362 (0.249) g/L]. No significant difference was found in the distributions of apo(a) phenotypes between the controls, the APR patients with hypoalbuminaemia, and the APR patients with normoalbuminaemia (P = 0.183). In the APR patients, the serum concentrations of AAT and Hp were respectively 2.709 (0.822) g/L and 2.631 (1.340) g/L, whereas those of normal controls were respectively 1.422 (0.219) g/L (P < 0.001) and 0.956 (0.442) g/L (P < 0.001). In conclusion, the Lp(a) is one of the acute phase reactants whose synthesis concurrently increases with other APRs, especially those with a high sialic acid content. The increase of the serum Lp(a) concentrations in the APR patients is not related to serum albumin concentration.

Fibrinogen gene polymorphism in a non-Caucasian population.

OBJECTIVE: The purpose of this study was to investigate the two polymorphisms of fibrinogen gene (RsaI and MnlI RFLPs in the coding region of the fibrinogen gene) in Koreans, and their relation to plasma fibrinogen. METHODS: Using PCR-amplified DNAs, RsaI and MnlI RFLPs were analyzed in 112 patients with coronary artery disease (CAD) and 137 healthy subjects. To compare the mean of plasma fibrinogen and lipid levels among different genotypes, one-way analysis of variance (ANOVA) test was performed. RESULTS: Allele frequencies of fibrinogen gene polymorphism in Koreans were not significantly different between CAD and control groups; fibrinogen polymorphism in this population showed a lack of association with plasma fibrinogen levels, but significant association with BMI (p < 0.05). CONCLUSION: This evidence suggests that in Korean populations, fibrinogen gene polymorphism is not a factor in the expression of atherosclerosis. There might, however, be an association between fibrinogen gene and obesity in such population.

Macular hole surgery in conjunction with endolaser photocoagulation.

PURPOSE: To determine whether endolaser photocoagulation to the retinal pigment epithelium at the base of a macular hole increases the anatomic success rate of surgery. METHODS: In a prospective consecutive clinical trial, eight eyes of seven patients with idiopathic macular hole underwent vitrectomy with posterior cortical vitreous removal and peeling of visible epiretinal membrane when present. A single shot of argon endolaser photocoagulation was applied to the retinal pigment epithelium at the center of the macular hole with a duration of 0.05 to 0.2 seconds and an intensity of 50 to 200 mW. After fluid-gas exchange was performed with 14% perfluoropropane gas, patients maintained face-down positioning for 2 weeks. RESULTS: One eye with stage 2 macular hole, six eyes with stage 3 macular hole, and one eye with stage 4 macular hole were included. All eight eyes had a closed macular hole (100% anatomic success rate) at final examination 6 to 12 months after surgery. Best-corrected visual acuity improved 3 or more lines on the Early Treatment Diabetic Retinopathy Study visual acuity chart in all eyes. Four (50%) of the eight eyes had a final visual acuity of 20/40 or better. CONCLUSIONS: Endolaser photocoagulation may be a useful adjunct to macular hole surgery but requires further investigation and long-term evaluation.

The risk groups for coronary heart disease in Koreans. Assessment by distribution of serum lipid concentrations.

Coronary heart disease is the most severe form of disease caused by atherosclerosis; and there is a strong relationship between serum lipid concentrations and atherosclerosis. By decade of life, means, standard deviations and selected percentiles were calculated according to sex for serum concentrations of total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglyceride in 69,563 Koreans. The prevalence of dyslipoproteinemias which were related to high risk of coronary heart disease were assessed. The mean concentrations of serum total cholesterol and LDL-C in the Korean population were 5.02 mmol/l and 3.00 mmol/l. The 75th and 90th percentile concentrations of total cholesterol were 5.59 mmol/l and 6.24 mmol/l. The mean concentrations of serum triglyceride and HDL-C were 1.58 mmol/l and 1.30 mmol/l. The hyperlipoproteinemia type IV (4.8%) was the most frequent, followed by Type IIa (4.6%), hypoalphalipoproteinemia (3.3%), and type IIb (0.2%). According to the National Cholesterol Education Program Adult Treatment Panel II, 4.1% of Korean adults needed the initial drug therapy and 10.8% the initial dietary therapy for hypercholesterolemia. The age and sex-specific treatment guidelines for hypercholesterolemia would make it possible that early intervention could be applied to atherosclerosis in Korean adults.

Association between apolipoprotein(a) polymorphism and Lp(a) levels in Koreans.

In view of the clinical importance of lipoprotein(a) [(Lp(a)] in coronary artery disease (CAD), we investigated the apo(a) size polymorphism, sequence polymorphisms of five base repeats [(TTTTA)n] in the noncoding region, and of Met/Thr in the coding region of the apolipoprotein(a) [apo(a)] gene. The apo(a) polymorphisms were examined in 184 Korean patients with CAD and 121 healthy subjects. In size polymorphism, there was an inverse association between plasma Lp(a) levels and the apo(a) isoforms in the CAD group (p < 0.005). For (TTTTA)n sequence polymorphism, subjects with the 8/8 genotype were most frequently observed in the two groups. Plasma Lp(a) levels showed a significant difference between the 8/5 versus the 8/8 genotype in the CAD group. On the other hand, Lp(a) levels varied significantly among the genotypes of a Met/Thr polymorphism in normal controls (P < 0.01). The heterozygous genotype had an intermediate level of Lp(a) between the two homozygous genotypes, thereby showing gene dosage effect. Thus, it is possible that the apo(a) polymorphisms are responsible for variations in the Lp(a) levels.

Uptake of acetylated peptides from the small intestine in sheep and their nutritive value in rats.

Acetylation is a potential method for protecting dietary peptides from degradation by rumen micro-organisms. As a first step in determining the nutritive value of acetylated peptides, their disappearance in the small intestine of sheep and their ability to support growth in a rat bioassay were measured. 15N-labelled peptides were prepared from lucerne which had been grown with 15N-labelled (NH4)2SO4 in the absence of Rhizobium. Peptides were prepared by enzymic hydrolysis of the extracted protein. Two peptide preparations were made using different proteinase mixtures. These mixtures contained peptides with an average molecular weight of 559 and 522 Da. They were treated with acetic anhydride, which resulted in 85 and 88% modification respectively, and their uptake from the small intestine was determined by injecting 1 g of untreated or acetylated peptides in a Cr-EDTA solution into the jejunum of two sheep fitted with jejunal catheters and ileal cannulas. Ileal digesta were collected and analysed for Cr and 15N. The uptake of dialanine (Ala2) and N-acetyl-Ala2 were compared in a similar way. The disappearance of 15N from lucerne peptides was high (88 and 93% respectively) and this was not affected significantly by acetylation (86 and 87%). Corresponding values for Ala2 and N-acetyl-Ala2 were both 96%, as measured by HPLC. It was therefore concluded that acetylation did not affect the uptake of peptides from the small intestine in sheep. Two feeding trials were carried out with rats. The first trial was carried out with a protein-free diet to which was added 10% lactalbumin or 5% lactalbumin and then a mixture of methionine-free amino acids, either alone or supplemented with Met, Gly-Met or acetylated Gly-Met. The rats grew equally well on all sources of Met, but failed to grow significantly on the mixture of Met-free amino acids. In the second trial the diet contained casein as 5.9% of the basal diet. Additional casein, pancreatic casein hydrolysate (peptides) and acetylated pancreatic casein hydrolysate (acetylated peptides) were compared as sources of amino acids, at inclusion rates of 100 g/kg final diet. Feed intake was similar with casein and peptides treatments, but was depressed by 23% with acetylated peptides. Live weight gain was 15 and 75% lower with the peptides and acetylated peptides diets respectively. Addition of lysine, arginine or histidine did not restore feed intake or weight gain of rats receiving acetylated peptides, but feed intake was restored immediately when peptides replaced acetylated peptides. When intake was restricted to 9 g/d and acetylated casein hydrolysate replaced half of the protein in the diet, rats gained weight less rapidly (1.44 v. 1.09 g/d) and retained less N, such that only 0.36 of the acetylated peptide-N was calculated to remain available to the animal. This N retention compared with 0.70 for unmodified casein. Thus, the rat bioassay indicated that certain specific peptides may well be of high nutritive value following acetylation, but that there may be problems of inappetance and inefficient utilization with acetylated peptide mixtures.