Radiographic Union Assessment in Surgically Treated Distal Femur Fractures: A Systematic Review

BACKGROUND

Distal femur fractures are known to have challenging nonunion rates. Despite various available treatment methods aimed to improve union, optimal interventions are yet to be determined. Importantly, there remains no standard agreement on what defines radiographic union. Although various proposed criteria of defining radiographic union exist in the literature, there is no clear consensus on which criteria provide the most precise measurement. The use of inconsistent measures of fracture healing between studies can be problematic and limits their generalizability. Therefore, this systematic review aims to identify how fracture union is defined based on radiographic parameters for surgically treated distal femur fractures in current literature.

METHODS

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, Medline, EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science Core Collection databases were searched from inception to October 2022. Studies that addressed surgically treated distal femur fractures with reported radiographic union assessment were included. Outcomes extracted included radiographic definition of union; any testing of validity, reliability, or responsiveness; reported union rate; reported time to fracture union; and any functional outcomes correlated with radiographic union.

RESULTS

Sixty articles with 3,050 operatively treated distal femur fractures were included. Operative interventions included lateral locked plate (42 studies), intramedullary nail (15 studies), dynamic condylar screw or blade plate (7 studies), dual plate or plate and nail construct (5 studies), distal anterior-posterior/posterior-anterior screws (1 study), and external fixation with a circular frame (1 study). The range of mean follow-up time reported was 4.3 to 44 months. The most common definitions of fracture union included "bridging or callus formation across 3 of 4 cortices" in 26 (43%) studies, "bony bridging of cortices" in 21 (35%) studies, and "complete bridging of cortices" in 9 (15%) studies. Two studies included additional assessment of radiographic union using the Radiographic Union Scale in Tibial fracture (RUST) or modified Radiographic Union Scale in Tibial fracture (mRUST) scores. One study included description of validity, and the other study included reliability testing. The reported mean union rate of distal femur fractures was 89% (range 58%-100%). The mean time to fracture union was documented in 49 studies and found to be 18 weeks (range 12-36 weeks) in 2,441 cases. No studies reported correlations between functional outcomes and radiographic parameters.

CONCLUSION

The current literature evaluating surgically treated distal femur fractures lacks consistent definition of radiographic fracture union, and the appropriate time point to make this judgement is unclear. To advance surgical optimization, it is necessary that future research uses validated, reliable, and continuous measures of radiographic bone healing and correlation with functional outcomes.

LEVEL OF EVIDENCE

Level IV. See Instructions for Authors for a complete description of levels of evidence.

[Laparoscopic transchiatal access in Boerhaave syndrome]

Diagnosis of spontaneous rupture of the esophagus (Boerhaave syndrome) followed by purulent mediastinitis and pleural empyema has now been greatly simplified due to CT. The main thing is to suspect this syndrome in a timely manner. Methods of surgical treatment of this disease are still being discussed. We present successful laparoscopic treatment of spontaneous rupture of the esophagus.

Improving the bioavailability of manganese and meat quality of broilers by using hot-melt extrusion nano method

1. Mineral excretion is an issue in the poultry industry. The use of micro minerals in nano form can increase bioavailability and decrease excretion rate. However, information concerning the bioavailability of nano manganese (Mn) in broiler chicks is limited.2. This experiment studied the influences of hot-melt extrusion (HME)-processed manganese sulphate on body weight gain, Mn bioavailability, nutrient digestibility and meat quality in broiler chicks fed a corn-soybean meal-based diet as a starter and grower phase. A total of 700 birds (Ross 308, 1-day-old) were randomly placed in 35 cages (20 birds per cage). The broiler chicks were fed one of seven experimental diets, which consisted of a control (without supplemental Mn), different levels of MnSO₄ (IN-Mn60; 60, 120, and 200 mg/kg), or HME MnSO₄ (HME-Mn; 60, 120, and 200 mg/kg).3. There was an increased serum Mn content in broilers fed diet supplemented with HME-Mn. In the grower phase, increased dietary Mn levels elevated the concentrations in the serum, liver, and tibia. There were increases in the excreta Mn content of broilers fed increasing levels. The supplementation of HME-Mn showed a lower percentage of abdominal fat compared with the IN-Mn treatment diets. Supplementation with HME-Mn decreased intramuscular fat compared with the diets supplemented with IN-Mn. The supplementation of HME-Mn decreased the thiobarbituric acid reactive substances (TBARS) at d 6 of age. The HME-Mn source showed a greater decrease in TBARS compared with the IN-Mn treatment.4. In conclusion, HME processing increased bioavailability and could be used as an environmentally friendly method to facilitate lower levels of Mn in the diet of broiler chickens.

Comparison of five membrane filters to collect bioaerosols for airborne microbiome analysis

AIMS

Recovering DNA of airborne micro-organisms (AM) from air is a challenging task. We compared five membrane filters for bioaerosol sampling-mixed cellulose ester (MCE), polyethersulfone (PES), polyamide (PA), polytetrafluorethylene (PTFE) and polyvinylidene fluoride (PVDF)-based on their bacterial, fungal and eukaryotic DNA recoveries.

METHODS AND RESULTS

Bacterial, fungal and eukaryotic populations were quantified using quantitative PCR. With a bacterial consortium, PTFE exhibited the best recovery efficiency (113%), followed by PA (92%), PES (86%), MCE (48%) and PVDF (1%). When filters were compared with air, PA was used as a control to normalize results from the others. The bacterial, fungal and eukaryotic DNA recovery ratios were markedly greater in PES (9·3, 11·5 and 10·3 respectively) than in the remaining. Eukaryotic MiSeq sequencing revealed that PES recovered a more diverse and considerably richer assemblage (richness ratios, 4·97 vs ≤ 1·16 for PES vs the others). Rank abundance distribution analysis showed that distribution tails were longer (>4 times) in PES, but these did not differ between the remaining and PA. Community comparison showed that PES exhibited a lower variation across trials than the PA, while the remaining did not.

CONCLUSIONS

PES filter markedly outperformed the other filters in quantitative and qualitative recovery of AM.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our findings demonstrated the importance of filter selection for sampling AM.

[Pulmonary insufficiency in acute stroke: risk factors and mechanisms of development]

Various degrees of pulmonary insufficiency (PI) (PaO₂ ≤60 mm Hg, SaO₂ ≤90%) are diagnosed in most of patients with severe acute stroke (AS). Frequency and severity of PI positively correlates with the severity of AS. PI worsens patient's condition, prolongs the hospitalization period, and increases the probability of fatal outcome. Early clinical signs of PI may be undiagnosed due to the severity of stroke and thus not treated. The initiating pathogenic mechanism of PI is stress-related activation of sympathetic nervous system (SNS) and systemic immunosuppression. In severe stroke with mass effect, the rapid and significant increase in intracranial pressure may additionally activate the SNS. Risk factors of PI include older age, previous pulmonary disease, prolonged supine position, respiratory muscle dysfunction, apnea, and concomitant somatic diseases. Decompensation of somatic diseases leads to multiple stage reactions with facilitation of functional and morphologic changes in the pulmonary system, hypoxemia and hypoxia, promotes infectious complications and multiple organ failure and worsens neurological outcome. Diagnosis and treatment of PI in AS decreases mortality and improves rehabilitation prognosis.

Effects of quorum quenching on temporal succession of activated sludge microbial community in a membrane bioreactor

AIMS

Quorum quenching (QQ) is an attractive strategy for mitigating biofouling in membrane bioreactors (MBRs). However, the effects of QQ on the activated sludge (AS) process have not been adequately evaluated. This study investigated the long-term effects of QQ on a laboratory-scale anoxic-oxic MBR, focusing on AS performance and microbial community.

METHODS AND RESULTS

Anoxic-oxic MBRs with and without QQ were operated for 91 days. QQ did not affect COD and TN removal efficiencies over the experimental period, during which its activity remained >90%. QQ reduced floc size by approximately 8% but had no effect on biomass concentration. AS microbial communities were regularly analysed using massively parallel sequencing. AS bacterial communities were temporally dynamic irrespective of QQ presence, for example, a temporal increase in bacterial diversity and a temporal decay of community similarity. QQ counteracted the temporal change in diversity and the temporal distance-community decay. Community comparison revealed that QQ changed the successional trajectory of the AS community at a late period, because it decelerated temporal changes of specific members, such as Thiothrix and Sphingomonadaceae*. Correlation networks revealed that QQ increased network clustering, complexity and density. The combined results suggest that the tighter microbial association by QQ increased the community resistance.

CONCLUSIONS

QQ can enhance the diversity and stability of the AS community in MBR by counteracting the innate temporal change in community structure.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our findings are useful for the further advancement of QQ-based strategies in engineered microbial environments.

Risk of malignancy in patients with psoriasis: a 15-year nationwide population-based prospective cohort study in Korea

BACKGROUND

The association between psoriasis and risk of malignancy has not been thoroughly evaluated in a large longitudinal cohort of Asian population.

OBJECTIVE

To determine the long-term risk of malignancy in Korean adult patients with psoriasis.

METHODS

We conducted a nationwide population-based prospective cohort study with a 15-year observational period. During the baseline period (1997-2000), total 1 773 786 Korean subjects who received health insurance from the National Health Insurance System were enrolled and 5788 subjects were defined as a psoriasis group. The number of new-onset malignancy was collected during the observational period (2001-2015).

RESULTS

Patients with psoriasis had a higher adjusted hazard ratio (aHR) for development of overall malignancy [aHR 1.08, 95% confidence interval (CI) 1.00-1.18] and gastric cancer (aHR 1.31, 95% CI 1.08-1.58) compared to controls. The risks of non-Hodgkin lymphoma and non-melanoma skin cancer were significantly increased only in patients with psoriasis who received systemic treatments (aHR 2.86, 95% CI 1.07-7.61 and aHR 3.93, 95% CI 1.47-10.47, respectively).

CONCLUSION

Psoriasis is associated with long-term risk for overall malignancy in Koreans, which was primarily driven by the increased risk of gastric cancer.

Abstract OT2-04-02: A phase 3 study of post-lumpectomy radiotherapy to whole breast + regional lymph nodes vs whole breast alone for patients with pN1 breast cancer treated with taxane-based chemotherapy (KROG 1701): Trial in progress

Background

In patients with early stage breast cancer, regional nodal irradiation (RNI) is added to whole breast irradiation (WBI) in order to control microscopic regional disease and to prevent systemic spread of cancer. According to recent randomized trials (MA.20 and EORTC 22922-10925), prophylactic RNI was associated with improvement in disease-free survival (DFS) in the patients with high-risk node negative or pN1 breast cancer. However, systemic agents now known to improve loco-regional control, such as taxane or endocrine therapy, were prescribed to a small percentage of patients in the studies. The benefit of RNI found in the previous studies might be attributed to incorporation of less effective systemic treatments. The impact of prophylactic RNI in pN1 breast cancer should be evaluated in the patients receiving modern systemic treatment. The current study was conducted to compare the effect of post-lumpectomy WBI vs WBI plus RNI on DFS in pN1 breast cancer patients who received adjuvant taxane-based chemotherapy.

Methods

This study is a multicenter, phase 3, randomized controlled non-inferiority trial (NCT03269981). Eligibility criteria are ≥ 20 years female; pathologically proven invasive carcinoma of the breast; one to three positive axillary lymph nodes (pN1) in pathologic specimen; receiving breast-conserving surgery followed by taxane-based chemotherapy; having adjuvant endocrine therapy or anti-HER2 treatment according to molecular subtype of tumor. Patients are randomly assigned in a 1:1 ratio to receive WBI or WBI plus RNI. Patient randomization was stratified by molecular subtype of tumor (i.e. luminal A/luminal B/luminal HER2/HER2-enriched/triple-negative) and methods of axillary management (i.e. sentinel lymph node biopsy/axillary lymph node dissection). The primary outcome is DFS. The secondary outcomes include DFS according to molecular subtype, treatment-related toxicity, and patient's quality of life per EORTC QLQ-C30 and QLQ-BR23. Patients will be followed for survival and disease recurrence for seven years. A total of 1,926 patients are planned to be enrolled, with recruitment initiated in April 2017. As of June 2018, a total of 236 patients were enrolled.

Acknowledgement

This study was supported by a grant from the National R&D Program for Cancer Control, Ministry of Health & Welfare, Republic of Korea (grant number: HA17C0043010018).

Citation Format: Kim H, Park W, Choi DH, Ahn SJ, Kim SS, Kim ES, Lee JH, Lee KC, Kim JH, Lee H-S, Kim JH, Kim MY, Park HJ, Kim K, Song SH, Kwon J, Lee IJ, Kim TH, Kim TG, Chang AR, Cho O, Jeong BK, Ha B, Lee J, Ki Y. A phase 3 study of post-lumpectomy radiotherapy to whole breast + regional lymph nodes vs whole breast alone for patients with pN1 breast cancer treated with taxane-based chemotherapy (KROG 1701): Trial in progress [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-04-02.

A large-aperture strip-grid beam splitter for partially combined two millimeter-wave diagnostics on Korea Superconducting Tokamak Advanced Research

A large-aperture beam splitter has been developed for simultaneous operation of two millimeter-wave diagnostics employing different probe beams in the frequency and polarization, microwave imaging reflectometer (∼85 GHz X-mode), and collective scattering system (300 GHz O-mode), on the Korea Superconducting Tokamak Advanced Research device. The beam splitter was designed based on a polarizer concept (i.e., grid of metal strips on a thin dielectric sheet), and this can be an optimal solution for these two diagnostics. Fabrication of the strips with uniform sub-millimeter width and spacing on a large dielectric sheet was achieved with an etching technique, and the laboratory test results on the reflection and transmission ratio are in good agreement with design values.

Development of a novel methanotrophic process with the helper micro-organism Hyphomicrobium sp. NM3

AIMS

Microbial consortia can be more efficient at biological processes than single isolates. The purposes of this study were to design and evaluate a synthetic microbial consortium containing the methanotroph Methylocystis sp. M6 and the helper Hyphomicrobium sp. NM3, and develop a novel methanotrophic process for this consortium utilizing a dialysis membrane.

METHODS AND RESULTS

Hyphomicrobium increased the methane-oxidation rate (MOR), biomass and stability at a dilution rate of 0·067 day^-1 in fed-batch co-culture. qRT-PCR showed that Methylocystis population increased gradually with time, whereas Hyphomicrobium population remained stable despite cell washing, confirming synergistic population interaction. At 0·1 day^-1 , spiking of Hyphomicrobium effectively increased the methanotrophic activity, after which Hyphomicrobium population decreased with time, indicating that the consortium is optimal at <0·1 day^-1 . When Hyphomicrobium was grown in dialysis membrane within the bioreactor, MOR increased linearly up to 155·1 ± 1·0 mmol l^-1  day^-1 at 0·067, 0·1, 0·2 and 0·4 day^-1 , which is the highest observed value for a methanotrophic reactor.

CONCLUSIONS

Hyphomicrobium sp. NM3 is a promising helper micro-organism for methanotrophs. Hyphomicrobium-methanotroph consortia used concurrently with existing methods can produce an efficient and stable methane oxidation system.

SIGNIFICANCE AND IMPACT OF THE STUDY

This novel methanotrophic process is superior to those previously reported in the literature, and can provide efficient and stable methane oxidation.

Development of inorganic and organic hybrid nanocoating based on carbon nanotubes for corrosion resistance

In this study, we report the synthesis and characterization of novel hybrid nanocoating based on carbon nanotubes (CNTs) on anodized aluminum surfaces (AAO). The hybrid nanocoating was deposited by number of methods which include spray coating, spin coating and dip coating. The bonding of nanocoating with metal surface is an important parameter for successful modification of the metal surfaces. The improved adhesion of nanocoating on metal surfaces could be attributed to chemical bonding of sol-gel nanocoating with anodized surfaces. The nanocoated anodized aluminum surfaces showed superior adhesion and excellent anticorrosive properties. The nanocoated panels showed enhanced galvanic protection comparable to 80% of titanium metal as determined by galvanic corrosion measurements. It also showed higher thermal conductivities than stainless steel and bare anodized surfaces.

The adequacy of the distal resection margin after preoperative chemoradiotherapy for rectal cancer

AIM

The study aimed to determine the adequacy of the distal margin in patients having preoperative chemoradiotherapy (CRT) followed by restorative surgery for rectal cancer.

METHOD

A total of 368 patients with locally advanced rectal cancer treated for cure at our institution between July 1999 and March 2009 were included in the study. All underwent preoperative CRT and sphincter-sparing surgery. The distal margin and other factors were examined for their effect on recurrence and survival. The median duration of follow-up was 48 months.

RESULTS

The length of distal margin ranged from 0 to 9.0 cm (median 1.5 cm). The pelvic control and disease-free survival rates at 5 years for patients with a margin of ≤ 3 mm were no different from those in whom it was > 3 mm (P = 0.6 and 0.8). The 5-year pelvic control rates between the ≤ 3 mm and > 3 mm groups were 66.7 and 86.2% in patients with a ypT3-4 tumour (P = 0.049) and 70.0 and 89.1% in patients who showed no response to CRT (P = 0.039).

CONCLUSION

The results suggest that a distal margin of < 3 mm in the surgical specimen after preoperative CRT is associated with a lower rate of pelvic tumour control at 5 years in patients with Stage ypT3-4 tumours or in those who do not respond to CRT.

Estimation of size of cord blood inventory based on high-resolution typing of HLAs

Methods for estimating the cord blood (CB) inventory size required vary according to the ethnic diversity of the HLA, degree of HLA matching and HLA-typing resolution. We estimated the CB inventory size required using 7190 stored CB units (CBU) and 2450 patients who were awaiting or underwent allogeneic hematopoietic stem cell transplantation. With high-resolution typing of HLA-A, B and DRB1, 94.6% of Korean patients could find CBUs in 100 000 CBUs with a 5/6 match, and 95.7% could find CBUs in 5000 CBUs with a 4/6 match. With low-resolution typing of HLA-A and B and high-resolution typing of leukocyte antigen-DRB1, 95% of patients could find CBUs in 50 000 CBUs with a 5/6 match, and 96.7% could find CBUs in 3000 CBUs  with a 4/6 match. With additional high-resolution typing for HLA-A and B, which could improve transplantation outcome, the size of the CB inventory would need to increase twofold for Koreans.

Association of KIR genes and HLA-C alleles with HPV-related uterine cervical disease in Korean women

This study investigated whether killer-cell immunoglobulin-like receptor (KIR) genes and human leukocyte antigen (HLA)-C alleles, receptors and ligands of natural killer cells are associated with the development of human papillomavirus (HPV)-related cervical disease in Korean women. Blood samples from 132 women with HPV-related cervical disease and 159 women without HPV infection were collected for genotyping of KIR genes and HLA-C alleles. Although no relationship was found between KIR genes and HPV-related cervical disease, a significant relationship was found between HLA-C alleles as ligands of KIR and HPV-related cervical disease. Women with HPV-related cervical disease were found to be significantly more likely to carry HLA-C*0303, particularly those with HPV 16 or 18 infection, and less likely to carry HLA-C*01 compared to women without HPV infection. HLA-C*0303 was found to confer susceptibility to HPV-related cervical disease, whereas HLA-C*01 was found to confer a protective effect against HPV-related cervical disease.

A comparison of inflammatory mediator expression between palmoplantar pustulosis and pompholyx

BACKGROUND

Both palmoplantar pustulosis (PPP) and pompholyx are clinically characterized by acute eruptions of vesicles or pustules on the palms or soles.

OBJECTIVES

This study aims to compare the expression of certain inflammatory mediator genes and proteins between patients with PPP and pompholyx using skin tissue samples.

METHODS

Skin biopsies obtained from lesional skin from patients with PPP (n = 7) and pompholyx (n = 5) were analysed by quantitative RT-PCR to measure the mRNA levels of nine genes, including IL-4, IL-8, IL-9, IL-17, IL-22, IFN-γ, CCL-20, granzyme and perforin. For immunohistochemical analysis, 34 paraffin-embedded skin specimens (PPP, n = 22; pompholyx, n = 12) were stained with anti-IL-8, IL-17A, IL-22 and granzyme B antibodies.

RESULTS

Of genes analysed, IL-8 and IL-17A mRNA expression levels were significantly higher in the PPP group than the pompholyx group (P = 0.012 in both), whereas the mRNA expression of granzyme B was significantly higher in pompholyx when compared with PPP (P = 0.004). Regarding the IL-17A immunohistochemical staining, tissue from the PPP lesions contained significantly more IL-17A(+) cells in both the epidermis and papillary dermis when compared with pompholyx (P < 0.001 and P = 0.019 respectively). Moreover, the intensity of the IL-8 immunoreactivity was also greater in the PPP skin lesions than the pompholyx tissue (P < 0.001).

CONCLUSIONS

IL-8 and IL-17A, both are increased in PPP tissue, may represent important immunologic mediators that help to differentiate this clinical entity from pompholyx. This study may provide useful clues in distinguishing PPP from pompholyx, as well as helping to understand the pathogeneses of these two diseases.

Fabrication and radio frequency characterization of carbon nanotube field effect transistor: evidence of quantum capacitance

We fabricated an radio frequency (RF) carbon nanotube field effect transistor (CNTFET) whose electrode shapes were standard RF designed ground-signal-ground (GSG)-type pads. The S-parameters measured from our RF CNTFET in the frequency range up to 6 GHz were fitted with an RF equivalent circuit, and the extracted gate capacitance was shown to be the capacitance value of the series combination of the electrostatic capacitance and the quantum capacitance. The effect of the channel resistance and the kinetic inductance was also discussed.

Enhancing effect of pretreatment with topical niacin in the treatment of rosacea-associated erythema by 585-nm pulsed dye laser in Koreans: a randomized, prospective, split-face trial

BACKGROUND

Rosacea is a chronic dermatosis that is usually confined to the face. A pulsed dye laser (PDL) system has been proven to be effective in treating rosacea-associated erythema and telangiectasias. Niacin is a cutaneous vasodilator that can increase the chromophore through increased blood flow.

OBJECTIVES

We hypothesized that increased blood flow by pretreatment with topical niacin could enhance the effect of PDL in the treatment of rosacea.

METHODS

Eighteen Korean patients with rosacea were recruited. Three sessions of 585-nm PDL using a subpurpuragenic dose with and without pretreatment with niacin cream were performed on randomly assigned half-faces at 3-week intervals. Erythema was assessed objectively by a polarization colour imaging system, and evaluations were also made by three blinded dermatologists. Patient satisfaction was evaluated using a 10-point visual analogue scale.

RESULTS

Fifteen patients completed this study. All patients showed an improvement in erythema after three sessions of PDL treatment both with and without niacin pretreatment (P = 0·023 and P = 0·009, respectively). There was no significant difference in the improvement of objective erythema between the two sides. However, based on physician assessment the overall clinical improvement on the niacin side was significantly higher (P = 0·005), and patient satisfaction was also higher on the niacin-pretreated side (P = 0·007). There were no remarkable side-effects, with the exception of transient erythema and oedema.

CONCLUSIONS

Pretreatment with topical niacin safely enhanced the effect of 585-nm PDL treatment of rosacea-associated erythema in Koreans. Application of niacin can be helpful in overcoming the relatively lower effect of subpurpuragenic PDL in dark-skinned Asians.

Association between interleukin-4R and TGF-β1 gene polymorphisms and the risk of colorectal cancer in a Korean population

AIM

Colorectal cancer is associated with inflammatory bowel disease. The mechanisms of how different genetic make-ups of cytokines might influence the individual susceptibility to develop particular types of tumours are still unknown. The authors analysed the association between genetic polymorphisms in cytokine/cytokine receptor genes and the risk of colorectal cancer in a Korean population.

METHOD

The authors assessed polymorphisms of the interleukin: IL-1, IL-1R, IL-2, IL-4, IL-4R, IL-10, transforming growth factor (TGF)-β1, IFN-γ genes in Korean patients with colorectal cancer (n = 170) and in a normal healthy control group (n = 130) to investigate the association between theses cytokine gene polymorphisms and the risk of colorectal cancer.

RESULTS

The IL-4R 1902*T allele was found to be associated with an increased risk of colon cancer (P < 0.01, OR = 2.0) and rectal cancer (P < 0.05, OR = 1.8). The IL-4R 1902*C allele was associated with a decreased risk of both colon cancer (P < 0.01, OR = 0.51) and rectal cancer (P < 0.05, OR = 0.5). The TFG-β1 10*T allele was found to be associated with an increased risk of colon cancer (P < 0.00, OR = 2.3) and the TFG-β1 10*C allele with a decreased risk of colon cancer (P < 0.00, OR = 0.43).

CONCLUSION

These results suggest that the genetic polymorphisms of IL-4R and TGF-β1 are associated with the risk of colorectal cancer in a Korean population.

Adoptive immunotherapy using human peripheral blood lymphocytes transferred with RNA encoding Her-2/neu-specific chimeric immune receptor in ovarian cancer xenograft model

The current gene transfer technology for single chain (scFv)-based chimeric immune receptor (CIR) has relied on retrovirus and lentivirus vectors which require a long time to obtain sufficient number of transduced cells and stably incorporate into genome. To ameliorate these limitations, we applied RNA electroporation to human peripheral blood lymphocytes (PBLs) activated with anti-CD3 antibody and interleukin-2 (IL-2) for 3 days and assessed that PBL transiently expressing anti-Her-2/neu CIR (CIR-PBL) containing signaling portion of CD28 and CD3zeta could elicit strong cytotoxicity in vitro and antitumor responses in vivo. The CIR-PBL expressed high level of CIR in CD4+, CD8+ and CD56+ cells. Her-2/neu-specific stimulation induced secretion of type-I cytokines including interferon-gamma (IFN-gamma), IL-8 and granulocyte-macrophage colony-stimulating factor, and IFN-gamma secretion was mainly mediated by CD8+ T cells. CIR-PBL specifically killed SKOV3 cell line expressing Her-2/neu. Adoptive transfer of CIR-PBL in SKOV3 xenograft model led to significant inhibition of tumor growth compared with transfer of mock-transduced PBL and showed higher inhibition than those with Herceptin, humanized monoclonal antibody specific for Her-2/neu. These results provided evidence that electroporation of CIR RNA to human PBLs could be used for rapid generation and high number of therapeutic antigen-specific T cells for adoptive immunotherapy.

Correlations of structure and rates of energy transfer for through-bond energy-transfer cassettes

Fluorescent DNA-labeling cassettes are designed to have a common absorbing chromophore matched to a single exciting laser wavelength, but up to four different emitters. Experiments reported here have examined the energy-transfer rates and fluorescence polarization characteristics for two different types of cassette, involving three distinct relative orientations of the donor and acceptor transition moments and the axis of the rigid linker. Energy-transfer times range from <200 fs to approximately 20 ps, the fastest transfer times occurring when the transition moments of the donor and acceptor species are aligned parallel to the linker axis. Experimental evidence is presented that supports a through-bond energy-transfer mechanism, in contrast with a commercial DNA-labeling agent, which exhibits much slower transfer times controlled by FRET. These rigid cassettes also exhibit polarized fluorescence from the acceptor species, so that this particular type of DNA-labeling probe has some of the advantages of single-molecule probes such as rhodamine and coumarin dyes.

Down-regulation of PPARgamma2-induced adipogenesis by PEGylated conjugated linoleic acid as the pro-drug: Attenuation of lipid accumulation and reduction of apoptosis

This study is designed to evaluate whether the PEGylated conjugated linoleic acid (PCLA) as the pro-drug can have favorable stability, bioavailability, and anti-adipogenic activity in 3T3-L1 cells for anti-obesity when compared with conjugated linoleic acid (CLA) itself. The CLA was simply coupled to poly(ethylene glycol) (PEG) at the melting state without solvents or catalysts through ester linkages between the carboxylic group of CLA and the hydroxyl group of PEG. To confirm of PCLA as the pro-drug, CLA release from PCLA was investigated by using high-performance liquid chromatographic (HPLC), showing that CLA release from PCLA was almost 90% in a nearly continuous fashion over the next 75h. Apoptosis was promoted by both CLA- and PCLA-treatments with increasing concentrations. However, the level of cell apoptosis induced by PCLA was lower than that induced by CLA owing to the biocompatible and hydrophilic properties of PEG. Moreover, the PCLA decreased glycerol-3-phosphate dehydrogenase (GPDH) activity in 3T3-L1 cells by acting upon major adipocyte marker proteins such as PPARgamma2, C/EBPalpha, and aP2 modulators. Furthermore, either CLA or PCLA stimulated basal, but not isoproterenol-sensitive, lipolysis in our cell model, suggesting that both CLA and PCLA may stimulate lipolysis via hormone sensitive lipase (HSL)-independent mechanisms. These results suggest that the PCLA may prove to be a stable pro-drug to control the deposition of fat in the human body, and that the anti-adipogenic effect of the PCLA on 3T3-L1 cells will offer a challenging approach for anti-obesity.

Endovascular treatment of intracranial vertebral artery dissections with stent placement or stent-assisted coiling

BACKGROUND AND PURPOSE

Endovascular treatment with stent placement or stent-assisted coiling was recently introduced as an alternative to parent artery occlusion in intracranial vertebral artery dissections. We describe the efficacy and limitations of this method.

METHODS

Fourteen patients with intracranial vertebral artery dissection were treated with stent placement (10 patients) or stent-assisted coiling (4 patients). Double overlapping stents were deployed in 4 of 10 patients with stent placement alone. Angiographic follow-up at 6 to 12 months was available in 13 patients.

RESULTS

In 13 patients with dissecting aneurysm, immediate angiographic outcomes were complete occlusion (1 patient), nearly complete (2 patients), and incomplete (10 patients). Follow-up angiograms of 12 of these patients showed complete occlusion (6 patients) and incomplete (6 patients; 1 unstable and 5 stable). Complete occlusion rates in follow-up angiograms were superior in double stent placement (75%) or stent-assisted Guglielmi detachable coil (GDC) embolization to stent placement alone (0%). There were no instances of postprocedural ischemic attacks, new neurologic deficits, and no new minor or major strokes before patient discharge. On the modified Rankin scale applied in follow-up, all patients were assessed as functionally improved or of stable clinical status.

CONCLUSIONS

Intracranial vertebral artery dissections were acceptably treated with stent placement or stent-assisted coiling, and the patency could be preserved at follow-up. However, the efficiency of stent placement alone for intracranial vertebral artery dissecting aneurysm was limited. Stent-assisted coil embolization or double stent placements are a viable alternative for complete occlusion of dissecting aneurysms.

Independent association of HLA-DR and FCgamma receptor polymorphisms in Korean patients with systemic lupus erythematosus

OBJECTIVES

To determine the distribution of HLA-DR type and FcgammaRIIa/IIIa polymorphisms, and to analyse the combined effects of these genes for susceptibility in Korean systemic lupus erythematosus (SLE) patients.

METHODS

A total of 299 SLE patients meeting 1982 ACR criteria and 144 Korean disease-free controls were enrolled. Genotyping for the FcgammaRIIa 131 R/H and FcgammaRIIIa 176 F/V was performed by polymerase chain reaction (PCR) of genomic DNA using allele-specific primers. HLA-DRB1 typing was performed by the PCR-SSOP method.

RESULTS

There was significant skewing in the distribution of the three FcgammaRIIa genotypes between the SLE patients and the controls [P = 0.002 for R/R131 vs R/H131 and H/H131, relative risk (RR) 2.6 (95% CI 1.3-5.2)], but not in FcgammaRIIIa genotypes. HLA-DRB1*15 allele was significantly more prevalent among SLE patients than the control population [P < 0.02, RR = 1.7 (1.1-2.6)]. HLA-DRB1 genotypes or allele frequencies of the SLE patients with nephritis did not differ significantly from those of the SLE patients without nephritis. We analysed the combined effects of the two candidate genes on SLE susceptibility. HLA-DRB1*15 allele was a significant predictor of SLE in individuals who were not homozygous for FcgammaRIIa-R/R131 [RR = 2.1 (1.2-3.7), P < 0.008], and the FcgammaRIIa-R/R131 genotype vice versa [RR = 5.3 (1.9-15.4), P < 0.001]. However, an additive or synergistic effect of both susceptible genes on relative risk for SLE was not evident.

CONCLUSIONS

Our results suggest that FcgammaRIIa-R/R131 homozygote and HLA-DRB1*15 allele are independent risk factors in Korean SLE patients without additive or synergistic effects.

Association between HLA-DR B1 and clinical features of adult onset Still's disease in Korea

OBJECTIVE

To determine whether HLA-DR alleles are associated with the development and clinical features of Adult Onset Still's Disease (AOSD) in Korea.

METHODS

Forty-seven patients (41 women, 6 men, mean age at diagnosis 31.6 yr) meeting Yamaguchi's criteria for AOSD and 144 healthy controls were enrolled in this study. The patients with AOSD were subdivided into groups according to their chronicity: monocyclic systemic, polycyclic systemic, and chronic destructive type, and were furthermore classified as non-articular, oligoarticular or polyarticular types (having arthritis involving 5 or more joints) according to the extent of articular involvement. HLA-DRB1 genotypes were assessed by PCR-SSOP.

RESULTS

Patients with AOSD had more frequent DRB1*12 (p = 0.028, relative risk (RR) = 2.27, 95% confidence interval (CI): 1.08-4.80) and DRB1*15 (p = 0.013, RR = 2.16, 95% CI: 1.17-4.00). They had less frequent DRB1*04 (p = 0.006, RR = 0.35, 95% CI: 0.16-0.75) compared to controls. DRB1*14 (p = 0.011, RR = 3.80, 95% CI: 1.27-11.31) were associated with the monocyclic systemic type.

CONCLUSION

Korean AOSD patients had more frequent DRB1*12 and DRB1*15, and less frequent HLA-DRB1*04. The patients with the monocyclic systemic type had more frequent DRB1*14 alleles. This study suggests that Korean AOSD patients have distinct immunogenetic profiles, and that it would be valuable to assess the relationships between HLA-DRB1 genes and polymorphisms of proinflammatory cytokines in the pathogenesis of AOSD.

Antiviral activities of extracts isolated from Terminalis chebula Retz., Sanguisorba officinalis L., Rubus coreanus Miq. and Rheum palmatum L. against hepatitis B virus

The antiviral effects of aqueous extracts of Terminalis chebula Retz., Sanguisorba officinalis L., Rubus coreanus Miq. and Rheum palmatum L. were examined by a cell culture system using a hepatitis B virus (HBV) producing cell line, HepG2 2.2.15. The extracts were assayed for the inhibition of HBV multiplication by measurement of HBV DNA and surface antigen (HBsAg) levels in the extracellular medium of HepG2 2.2.15 cells after an 8-day treatment. All extracts decreased the levels of extracellular HBV virion DNA at concentrations ranging from 64 to 128 microg/mL and inhibited the secretion of HBsAg dose dependently. Of the four tested plants, Terminalis chebula exhibited the most prominent anti-HBV activities.

Hepatocyte-specific gene expression by baculovirus pseudotyped with vesicular stomatitis virus envelope glycoprotein

We have developed the recombinant baculovirus pseudotyped with vesicular stomatitis virus (VSV) G protein. The VSV-G gene was under the control of the polyhedrin promoter so that it was expressed at high levels in infected insect cells but not in mammalian cells. The presence of VSV-G protein in purified baculovirus preparations was confirmed by Western analysis. This recombinant baculovirus also carried human AFP (alpha-fetoprotein) promoter for hepatocyte-specific gene expression. After an in vitro infection by a recombinant baculovirus carrying the luciferase gene under the control of human AFP promoter/enhancer (BacG-AFP-Luc(+)), the luciferase gene was expressed in AFP-producing Huh7, Hep3B, and HepG2 cell lines, but not in AFP-nonproducing cell lines. BacG-AFP-Luc(+) transduced with human hepatoma cells in vitro at an efficiency about fivefold greater than the recombinant baculovirus lacking VSV-G (the virus Bac-AFP-Luc(+)). The utilization of the AFP promoter/enhancer in a baculovirus vector could provide benefits in gene therapy applications.

Identification of HLA-A*11 variant (A*1107) in the Korean population

We report here a new HLA-A*11 allele, A*1107, identified by sequencing based typing in the Korean population. The full-length sequencing of A*1107 was conducted on cDNA. HLA-A*1107 differs from HLA-A*1101 by a single nucleotide at position 399 of codon 109 in exon3 (TTC-->TTA), leading to an amino acid change from phenylalanine to leucine. But the serological profile of HLA-A*1107 did not exhibit the altered HLA-A11.

Different distribution of HLA class II alleles according to response to corticosteroid therapy in sudden sensorineural hearing loss

OBJECTIVE

To investigate the association of HLA class II alleles with the susceptibility to sudden sensorineural hearing loss and with the results of corticosteroid treatment in the Korean population.

DESIGN

HLA-DRB1, -DQA1, -DQB1, and -DPB1 genotyping by the sequence-specific oligonucleotide probes method in 41 patients with sudden sensorineural hearing loss and in 206 healthy control subjects. Initial hearing levels at the onset of hearing loss and final hearing levels after treatment were evaluated for the association with HLA class II alleles.

SETTING

Tertiary care referral center, ambulatory and hospitalized care.

SUBJECTS

Forty-one patients (24 men and 17 women; mean age, 49.2 years) were compared with 206 controls. Patients were divided into 2 groups according to their response to corticosteroid therapy (good response vs nonresponse).

RESULTS

The frequencies of HLA-DRB1, -DQA1, -DQB1, and -DPB1 alleles were not significantly different between patients and controls (P>.05). When an association between the results of corticosteroid treatment and the frequency of HLA alleles was evaluated, the frequencies of HLA-DRB1*14 (relative risk [RR] = 3.5, P<.02), -DQA1*03 (RR = 4.2, P<.02), and -DQA1*05 (RR = 3.1, P<.03) were significantly increased, but HLA-DQA1*01 (RR = 0.2, P<.004) and -DQB1*06 (RR = 0.2, P<.009) were decreased in the group nonresponsive to corticosteroid therapy, compared with the controls. The distribution of HLA-DQA1*01 (P<.04), -DQB1*06 (P<.02), and -DQA1*03 (P<.003) was significantly different between the responsive and the nonresponsive groups. HLA-DQA1 allelic combination analysis showed that the frequencies of DQA1*03 and *05 had a high RR value in patients with sudden sensorineural hearing loss (RR = 4.1, P<.003) and in patients in the nonresponsive group (RR = 8.9, P<.001), compared with the controls.

CONCLUSION

The presence of HLA class II alleles may be a useful genetic marker in forecasting a prognosis in Korean patients with sudden sensorineural hearing loss.

Generation of cytotoxic T lymphocytes specific for human cytomegalovirus using dendritic cells in vitro

For the adoptive immunotherapy in immunodeficient bone marrow transplant recipients to prevent and treat human cytomegalovirus (HCMV)-associated diseases, HCMV-pulsed dendritic cells (DCs) were used as antigen-presenting cells for the induction of cytotoxic T lymphocytes (CTLs) specific to HCMV antigens in vitro. The antiviral CTL responses induced by HCMV-pulsed DCs were as highly efficient as those induced by HCMV-infected dermal fibroblasts, and endogenous viral gene expression was not required to induce virus-specific T-cell lines. The strong cytotoxic activity against HCMV-pp65, known as HCMV major antigen, was identified using autologous B lymphoblastoid cell line expressing pp65 antigen. The cytotoxic activity toward HCMV-infected target cells was found to be mediated primarily by CD8+ T cells, although both CD8+ cells and CD4+ cells were able to lyse autologous virus-infected target cells. The CTLs contained a mixture of effector cells that recognized virus peptides in the context of major histocompatibility complex. This system may be useful for defining the cellular immune response to HCMV and for the treatment of HCMV infection in immunocompromised patients.

Effects of intravenous infusion of amino acids and glucose on the yield and concentration of milk protein in dairy cows

To test the hypothesis that the availability of glucose or its precursors can influence the response of milk protein concentration to the intravenous infusion of amino acids, five cows were used in a 5 x 5 Latin square design with period lengths of 7 d. The five treatments were the basal diet of grass silage ad lib. plus 5 kg/d of a cereal-based supplement containing feather meal (Basal); Basal plus 4 g/d histidine, 8 g/d methionine and 26 g/d lysine (4H); Basal plus 8 g/d histidine, 8 g/d methionine and 26 g/d lysine (SH); and these two amino acid mixtures together with 600 g/d of gluctose (4HG and 8HG respectively). Earlier experiments with this basal diet had shown that histidine was first-limiting for secretion of milk protein, followed by methionine and lysine. The yield of milk protein was increased progressively with the amount of histidine infused. The efficiency of transfer of histidine into milk protein was 0.42 for the 4H and 4HG and 0.35 for the 8H and 8HG treatments, and the concentration of milk protein was increased over Basal by all infusion treatments. However, milk protein concentrations were higher, and lactose concentrations in the milk were lower, in the absence of added glucose. Concentrations of insulin in blood plasma were not affected by treatment. It is concluded that, with the treatments without added glucose, a shortage of glucose prevented an increase in lactose secretion, and hence limited the increase in milk yield, leading to an increased concentration of protein in the milk.

MICA 5.1 allele is a susceptibility marker for psoriasis in the Korean population

In order to investigate the possibility that the MICA gene is involved in the pathogenesis of psoriasis, microsatellite polymorphism in the transmembrane region of MICA was studied in 138 Korean patients with psoriasis and compared with 126 healthy controls. The MICA 5.1 microsatellite allele, consisting of 5.1 repetitions of GCT/AGC, showed significantly higher frequencies in all patients and in patients with type I psoriasis than in the controls. HLA-A30-B13-Cw*0602-MICA 5.1 and A1-B37-Cw*0602-MICA 5.1 were found to be an extended haplotype associated with psoriasis. Our results suggest that the MICA 5.1 allele might be a genetic marker related to the early onset of psoriasis and play a secondary role to the HLA-Cw*0602 gene or an unknown causative gene closely linked to HLA-Cw*0602 in the genetic susceptibility to psoriasis.

Distribution of seven polymorphic markers and haplotypes within the human TNF gene cluster in Koreans

We examined the distribution of polymorphic elements within the tumor necrosis factor (TNF) gene cluster in 133 normals and in 20 Korean families and compared our data with the results of Caucasians. The genotypes that are shown frequently are TNF a6 (33.8%), TNF b5 (46.6%), TNF c1 (79.3%), TNF d3 (34.6%), TNF e3 (86.5%), TNFB*2 (51.5%), and TNF(-308) A (91.4%). In comparison, TNFa 6 (33.8%), TNFa 13 (4.1%), TNFb 5 (46.6%), TNFd 1 (7.5%), TNFd 3 (34.6%), TNFe 3 (86.5%), TNFe 4 (6.8%), and TNF(-308) A (91.3%) were found more frequently in Koreans than Caucasians (p < 0.01). TNFa 14, TNFa 15, TNFd 8, and TNFe 4 alleles were found only in Korean controls. However, TNFb 6 and TNFb 7 alleles were not found in this study. From the TNF gene of TNFa, TNFb, TNFc, TNFn, TNF(-308), TNFd, and TNFe, 49 different TNF haplotypes were found in 20 Korean families. These data suggest that the TNF microsatellite haplotypes constitute a highly polymorphic system and that will provide useful information on the association between the TNF marker and the immune disease.

Effects of intra-abomasal infusion of beta-casomorphins on circulating concentrations of hyperglycaemic insulin and glucose in dairy cows

The effects of intra-abomasal infusion of a mixture of -casomorphins on circulating concentrations of insulin and glucose prestimulated by either abomasal (experiment 1) or intravenous (experiment 2) glucose were studied using non-lactating dairy cows. In both experiments, bolus infusion of 240 mg of a mixture of three beta-casomorphins (beta-casomorphin-4-amide, -5 and -7) was given via an abomasal infusion line. The beta-casomorphins significantly lowered the responses of serum insulin to both abomasal and intravenous glucose infusions (P<0.05). However, the beta-casomorphins did not significantly affect circulating glucose concentrations. The insulinopenic action of the beta-casomorphins is consistent with the action of somatostatin-28 (SS-28) as judged from the effects of SS-28 on the insulin secretion when administered intravenously in experiment 1.

Distribution of HLA-A, -B and -DRB1 alleles in patients with sudden sensorineural hearing loss

This study was performed to investigate the association between human leukocyte antigen (HLA) and susceptibility to sudden sensorineural hearing loss in the Korean population. HLA-A and HLA-B typing using a standard microlymphocytotoxicity technique and HLA-DRB1 genotyping were performed in 35 patients with sudden sensorineural hearing loss and in 206 healthy controls. Prednisone (usual dose 60 mg/day) was administered for 6 days and tapered for an additional 4-6 days. Both initial hearing levels at the onset of deafness and final hearing levels after treatment were examined and evaluated for association with HLA alleles. The frequency of HLA-DRB1*14 was increased in patients with sudden sensorineural hearing loss compared with controls (relative risk [RR] = 2.7, p = 0.016). The frequencies of HLA-A2, -A31, -B52, -B61, -DRB1*04, -DRB1*11 and -DRB1*12 were slightly higher than in the controls, but did not reach statistical significance. When an association between the treatment results and HLA alleles was also evaluated, the frequency of HLA-DRB1*04 was found to be increased in the patients who did not respond to steroid treatment compared with both patients who responded well to steroid (50%, vs 16%, p = 0.034) and controls (RR = 3.0, p = 0.046). These results suggest that there is an association between HLA-DRB1*14 and disease susceptibility and that the presence of HLA-DRB1*04 may be an useful marker for predicting a poor prognosis in Korean patients with sudden sensorineural hearing loss.

Interleukin-18 and the costimulatory molecule B7-1 have a synergistic anti-tumor effect on murine melanoma; implication of combined immunotherapy for poorly immunogenic malignancy

Interleukin-18 has been described recently as a cytokine secreted primarily by Kupffer cells. Furthermore, it has been shown that it has significant anti-tumor effects, which are mediated by T cells and natural killer cells, in a manner similar to interleukin-12. Here, we report the evaluation of the effects of the systemic administration of interleukin-18 in combination with B7-1 (CD80) expressed on tumor cells [interleukin-18 + B7-1] on the growth of murine B16 melanoma in vivo. After the subcutaneous inoculation of B16 melanoma, B16 tumors grew progressively in immunocompetent syngeneic C57BL/6 mice. Mice treated with either interleukin-18 or immunized with B7-1-transduced B16 did not demonstrate significant anti-tumor effect. The combination of the two treatments, however, resulted in dramatic suppression of melanoma formation, tumor growth, and a significant improvement in survival. Inhibitory effects of [interleukin-18 + B7-1] on lung metastasis in mice were also detected. Additionally, mice treated with [interleukin-18 + B7-1] showed an increase of natural killer cytotoxicity and interferon-gamma production in vivo. Unlike [interleukin-18 + B7-1], [interleukin-12 + B7-1] did not have a strong anti-tumor effect against B16 melanoma. Histologic characterization after the [interleukin-18 + B7-1] treatment confirmed the infiltration of natural killer cells into the tumor, suggesting that natural killer cells may be involved in the [interleukin-18 + B7-1]-induced anti-tumor effect. This finding was confirmed by showing that depletion of NK1.1+ cells before immunization inhibits the [interleukin-18 + B7-1]-induced anti-tumor effect. Depletion of CD3+ cells in vivo also decreased the anti-tumor effect of [interleukin-18 + B7-1], suggesting the importance of CD3+ T cells. Collectively, combination with interleukin-18 and B7-1 expression has synergistic anti-tumor effects against B16 murine melanoma.

Displaced intra-articular calcaneal fracture treated surgically with limited posterior incision

The incidence of calcaneal fracture has been slowly increasing; however, the ideal treatment for displaced intra-articular fracture is not available yet, even though the fracture brings frequent complication and disability. Between April 1991 and March 1998, we treated 103 displaced intra-articular calcaneal fractures of 92 patients surgically with limited posterior incision, modified Gallie approach. There were thirty-seven tongue-type fractures, fifteen tongue-type fractures with moderate comminution, nineteen joint-depression fractures, twenty-nine joint-depression fractures with moderate comminution, and three extensively comminuted fractures. The fracture fragments were fixed mainly with partly threaded small cancellous screws or Steinmann pins without any bone graft. Ankle and subtalar motion was permitted immediately if fixation were stable enough. Otherwise, a short period of cast immobilization was utilized. With a mean follow-up of 28 months (range, 12 to 66 months), eighty six percent of feet had no pain or only occasional pain not requiring medication. Using American Orthopedic Foot and Ankle Society hindfoot score system for assessment, ninety percent of feet rated as good to excellent. We used "Circle draw test" for evaluation of subtalar motion during follow-up visitation and found eight-seven percent of feet showed good to excellent correlation with the functional recovery. We recommend a limited posterior incision for reduction and internal fixation of displaced intra-articular calcaneal fractures. For displaced intra-articular fractures with three or four large fragments without further comminution and without a displaced fracture of the calcaneal cuboid joint, this method is particularly useful. We also recommend a Circle draw test for evaluation of subtalar joint motion as well as an indicator of functional recovery after displaced calcaneal fractures.

Corneal ectasia detected after laser in situ keratomileusis for correction of less than -12 diopters of myopia

We report 2 cases of corneal ectasia detected after laser in situ keratomileusis (LASIK) for the correction of less than -12.0 diopters (D) of myopia. Patients were evaluated before and after LASIK by corneal topography and pachymetry. After treatment, visual acuity temporarily improved but was followed by visual impairment, with corneal ectasia detected by topography. There may be a risk of corneal ectasia after LASIK in cases of myopia of less than -12.0 D. Despite thelow incidence, we recommend that LASIK be restricted to cases in which more than half the original corneal thickness and more than 250 microns of the stromal bed can be preserved. Careful examination, including preoperative serial topographic evaluation and measurement of posterior stromal thickness, should be performed to improve the quality and predictability of corneal refractive surgery.

The association of psoriasis with human leukocyte antigens in Korean population and the influence of age of onset and sex

To identify HLA markers that may contribute to the genetic susceptibility of Koreans to psoriasis, we studied 84 psoriasis patients, with serologic HLA types of A, B, and genotypes of HLA-Cw, DRB1, DQA1, DQB1, DPB1 alleles. The distribution of HLA markers and the associated haplotypes were analyzed according to age and sex. HLA-Cw*0602 showed the strongest association with psoriasis (relative risk = 36.0, p < 10-8, Pc < 8 x 10-7). The frequencies of A1 (relative risk = 17.0, p < 9 x 10-7, Pc < 7 x 10-5), A30 (relative risk = 5.5, p < 2 x 10-5, Pc < 0.001), B13 (relative risk = 5.6, p < 4 x 10-6, Pc < 3 x 10-4), B37 (relative risk = 30.3, p < 7 x 10-7, Pc < 6 x 10-5), DRB1*07 (relative risk = 5.9, p < 2 x 10-6, Pc < 8 x 10-5), DRB1*10 (relative risk = 26.4, p < 4 x 10-6, Pc < 3 x 10-4), DQA1*02 (relative risk = 6.2, p < 5 x 10-7, Pc < 4 x 10-4), DQB1*02 (relative risk = 2.5, p < 0.005, Pc = ns) and DPB1*1701 (relative risk = 24.6, p < 9 x 10-6, Pc < 7 x 10-4) were also significantly increased in Korean psoriasis patients. Type I and type II psoriasis were subdivided into groups of below and above 30 y of age, because of the significant difference found in HLA-Cw*0602 phenotype frequency between the two groups (83.9% vs. 54.5%, p < 0. 009). In addition to HLA-Cw*0602, the frequencies of B37 and DPB1*1701 were significantly higher in type I as opposed to type II psoriasis. HLA-A30-B13-Cw*0602-DRB1*07-DQA1* 02-DQB1*02 was identified as a high risk haplotype. This was particularly true at an early age in the female. HLA-A33-B44-Cw*1401-DRB1*13-DQA1* 01-DQB1*06-DPB1*0401 was defined as a protective haplotype for psoriasis. The extended haplotype HLA-A1-B37-Cw*0602-DRB1*10-DQA1*01-DQB1*05 was discovered to be a high-risk factor in Koreans. To summarize, this study demonstrates the differential association of HLA according to sex, and identifies a newly found high-risk haplotype and a protective haplotype in Korean psoriasis patients.

Association of HLA with Vogt-Koyanagi-Harada syndrome in Koreans

PURPOSE

To study the distribution of human leukocyte antigen HLA-A/B antigens and HLA-DR/-DQ/-DP alleles and to investigate the immunogenetic background of Korean patients with Vogt-Koyanagi-Harada (VKH) syndrome and clinical course with different types of HLA.

METHODS

Human leukocyte antigen typings were performed in 18 Korean patients with VKH syndrome and in 128 healthy control subjects. HLA-A/B loci serologic typing was performed according to the standard microlymphocytotoxicity technique. DNA was extracted through the salting out method, and HLA-DR phenotyping and HLA-DR4, HLA-DQ, and HLA-DP subtyping were performed with the polymerase chain reaction-sequence specific oligonucleotide probe (PCR-SSOP) method.

RESULTS

Among HLA-A/B antigens typed by the standard microlymphocytotoxicity method, the frequencies of HLA-A31 (RR = 6.1, P<1x10(-2)) and HLA-B55 (RR = 15.8, P<.05) were significantly increased in the patient group compared with the control group. Among HLA-DR/-DQ/-DP alleles subtyped by DNA methods, the frequencies of HLA-DRB1*04 (RR = 45.1, P<1x10(-7)) and HLA-DRB1*07 (RR = 3.2, P<.05) were significantly increased. However, significant decreases in HLA-DRB1*08 (RR = .1, P<.05), HLA-DRB1*13 (RR = .1, P<.05), and HLA-DRB1*14 (RR = .1, P<.05) frequencies were observed. The result of HLA-DR, HLA-DQ, and HLA-DP subtyping showed the significant increase in DRB1*0405 (RR = 45.1, P<1x10(-7)), DQA1*0302 (RR = 12.0, P<1x10(-4)), DQB1*0303 (RR = 5.0, P<1x10(-2)), DQB1*0401 (RR = 18.9, P<1x 10-6), and DPB1*0501 (RR = 3.8, P<.05). However, significant decreases in DQA1*0101 (RR = .1, P< .05), DQA10102 (RR = .1, P<1x10(-2)), DQA1*0103 (RR = .1, P<.05), DQA1*0501 (RR = .1, P<1x10(-2)), DQB1*0301 (RR = .1, P<.05), DQB1*0601 (RR = .1, P<.05), DPB1*0201 (RR = .3, P<.05), and DPB1*0401 (RR = .1, P<.05) frequencies were also observed. In patients with DRB1*0405 itself or HLA-DRB1*0405-DQA1*0302-DQB1*0401 haplotype, a reduction in visual acuity and ocular complications was common.

CONCLUSIONS

These results suggest that HLA-DRB1*0405 itself or HLA-DRB1*0405-DQA1*0302-DQB1*0401 haplotype is greatly increased and may play the most important role in the development and the clinical course of VKH syndrome in Korean patients.

H-ras, but not N-ras, induces an invasive phenotype in human breast epithelial cells: a role for MMP-2 in the H-ras-induced invasive phenotype

Elevated p21ras expression is associated with tumor aggressiveness in breast cancer including the extent of invasion into fat tissues, infiltration into lymphatic vessels and tumor recurrence. In the present study, we have examined the roles of H-ras and N-ras, members of the human ras gene family, in the pathogenesis of breast cancer. We show that H-ras, but not N-ras, induces an invasive phenotype in human breast epithelial cells (MCF10A) as determined by the Matrigel invasion assay, whereas both H-ras and N-ras induce anchorage-independent growth, as shown by soft agar assay. We examined the effects of H-ras and N-ras activation on the expression of MMP-2 and MMP-9, which can degrade type IV collagen, the major structural collagen of the basement membrane. We show that MMP-2 is efficiently induced by H-ras, whereas MMP-9 induction is more prominent in N-ras-activated MCF10A cells. We also show that H-ras-mediated invasiveness is significantly inhibited when the expression of MMP-2 is down-regulated, using an oligodeoxyribonucleotide complementary to the MMP-2 mRNA, or when MMP-2 activity is blocked by its inhibitor TIMP-2 (tissue inhibitors of matrix metalloproteinase-2). Our results show that the H-ras-induced invasive phenotype is associated more closely with the expression of MMP-2 in human breast epithelial cells, rather than the induction of MMP-9 expression, as shown previously for rat embryonic fibroblasts.

DQCAR 113 and DQCAR 115 in combination with HLA-DRB1 alleles are significant markers of susceptibility to rheumatoid arthritis in the Korean population

We have investigated HLA region microsatellite polymorphisms in rheumatoid arthritis (RA) which are known to be associated with HLA class II alleles in the Korean population. Ninety patients with RA and 106 controls were employed for this study, in which TAP1CA, DQCAR, D6S273, HLA-DRB1, -DQA1 and -DQB1 allele typing were performed. DQCAR 113 (RR = 3.2, P<0.0002), DQCAR 115 (RR = 3.6, P<0.0001) and heterozygous DQCAR 113/115 (RR = 11.2, P<0.0001) frequencies were significantly increased in the RA group compared with the control group. The HLA-DRB1 genotypes of patients who had DQCAR 113/115 alleles were defined as DRB1*04 and/or DRB1*09. There was no significant difference between RA and controls in D6S273 and TAP1CA allele frequencies. We demonstrated that HLA-DRB1*0405 (RR = 6.6, P<10(-6)), DQA1*03 (RR = 5.2, P<10(-6)), DQB1*04 (RR = 3.5, P<0.002) alleles were useful markers of susceptibility to RA in Koreans. The frequency of HLA-DRB1*0405 was higher in DQCAR 113 allele-positive RA (68.1%) than in DQCAR 113 allele-negative (16.3%) and total RA (43.3%) groups, and the susceptibility risk of DQCAR 113 allele to RA was more increased in the DRB1*0405-positive group (RR = 5.5, P<0.04). On the other hand, DQCAR 115 allele was more significantly associated with susceptibility to RA in HLA-DRB1*0405-negative patients (RR = 5.1, P<0.0005), and the association between RA and HLA-DRB1*0405 was also significantly associated with DQCAR 115 allele-negative patients (RR = 13.2, P<0.00001) as compared with DQCAR 115 allele-negative control groups. HLA-DRB1*0405-DQA1*03-DQCAR113-DQB1*03 haplotype showed high relative risk value (RR= 17.7, P<0.0002). In conclusion, the DQCAR allele in combination with HLA class II, especially DR, is probably a useful risk marker for RA susceptibility in the Korean population.

Modulation of chemical carcinogen-induced unscheduled DNA synthesis by dehydroepiandrosterone (DHEA) in the primary rat hepatocytes

Modulation of unscheduled DNA synthesis by dehydroepiandrosterone (DHEA) after exposure to various chemical carcinogens was investigated in the primary rat hepatocytes. Unscheduled DNA synthesis was induced by treatment of such direct acting carcinogens as methyl methanesulfonate (MMS) and ethyl methanesulfonate (EMS) or procarcinogens including benzo(a)pyrene (BaP) and 7,12-dimethylbenz(a)anthracene (DMBA). Unscheduled DNA synthesis was determined by measuring [methyl-3H]thymidine radioactivity incorporated into nuclear DNA of hepatocytes treated with carcinogens in the presence or absence of DHEA. Hydroxyurea (5x10(-3) M) was added to growth medium to selectively suppress normal replication. DHEA at concentrations ranging from 1x10(-6) M to 5x10(-4) M did not significantly inhibit unscheduled DNA synthesis induced by either MMS (1x10(-4) M) or EMS (1x10(-2) M). In contrast, DHEA significantly inhibited unscheduled DNA synthesis induced by BaP (6.5x10(-5) M) and DMBA (2x10(-5) M). DHEA-induced hepatotoxicity in rats was examined using lactate dehydrogenase (LDH) release as an indicator of cytotoxicity. DHEA exhibit no significant increase in LDH release compared with the solvent control at 18 h. These data suggest that nontoxic concentration of DHEA does not affect the DNA excision repair process, but it probably influence the enzymatic system responsible for the metabolic activation of procarcinogens and thereby decreases the amount of the effective DNA adducts formed by the ultimate reactive carcinogenic species.

Corneal perforation during laser in situ keratomileusis

Two cases of corneal perforation that occurred during laser ablation but not during flap formation in laser in situ keratomileusis (LASIK) are reported. In the first case, no problem in flap formation occurred, and stromal bed thickness was assumed to be about 239 microns after laser application. However, a stromal bed perforation was found when 608 pulses were applied (theoretical ablation depth was 140 microns). Excessive dehydration due to prolonged exposure to the operating microscope light may change the ablation rate and cause corneal perforation. In the second case, LASIK retreatment was performed using the original flap for correction of regressed myopia (-4.0 diopters). Although the stromal bed thickness was assumed to be about 175 microns after the laser application, a stromal bed perforation was found when 151 pulses were applied (theoretical ablation depth was 37 microns). Unexpected corneal ectasia after the first LASIK treatment may cause a corneal perforation in LASIK retreatment. In conclusion, excessive dehydration of the cornea should be avoided, and careful examination of the corneal shape is necessary to prevent corneal perforation during laser ablation in LASIK.

Characteristics of L-glutamine transport by lactating mammary tissue

The transport of L-glutamine by the lactating rat mammary gland has been investigated using rat mammary tissue explants and the in situ perfused rat mammary gland. L-glutamine uptake by both explants and the perfused mammary gland was via both Na(+)-dependent and Na(+)-independent pathways. It appeared that these pathways are situated on the blood-facing aspect of the mammary gland. L-glutamine uptake by both mammary preparations was markedly inhibited by 2-aminobicyclo[2,2,1]heptane-2-carboxylic acid in the absence of external Na+. This is consistent with L-glutamine uptake via system L. The Na(+)-dependent component(s) of L-glutamine uptake remains to be precisely identified. However, system A can be ruled out on the basis that L-glutamine was not inhibited by (methylamino)isobutyric acid. Mammary tissue concentrates L-glutamine with respect to both milk and plasma: we suggest that the Na(+)-dependent component(s) of L-glutamine uptake is responsible for generating the intracellular to extracellular concentration gradient.

Decreased tumour necrosis factor-beta production in TNFB*2 homozygote: an important predisposing factor of lupus nephritis in Koreans

Low TNF production and its association with TNF gene restriction fragment length polymorphism (RFLP) was demonstrated in (NZW/NZB) F1 mice. However, little is known about the significance of TNF production in association with TNF gene polymorphism in human SLE. This study was designed to evaluate the role of TNF production of peripheral blood mononuclear cells (PBMC) and its association with TNFB gene polymorphism in SLE, particularly lupus nephritis. TNFB gene polymorphism was defined by PCR-NcoI RFLP. TNF productions of phytohemagglutinin (PHA)-stimulated PBMC and T cells were examined by bioassay using L929 cell line and ELISA. The PBMC stimulated by PHA from patients with SLE (n = 60) tended to secrete less amounts of TNF by bioassay (1032 +/- 184 pg/ml vs 1524 +/- 224 pg/ml, P = 0.094), and TNF-beta by ELISA (P = 0.0082) than that from normal controls (n = 38). The low TNF-alpha producer was more frequent in nephritis than non-nephritis (34.4% vs 7.1% respectively, P < 0.01). TNF-beta also revealed similar results (53.1% vs 21.4%, P < 0.05). In SLE, mean production of TNF-beta was decreased in TNFB*2 homozygote (n = 18) than that in TNFB*1 homozygote (n = 9) (1126.3 +/- 145 pg/ml) vs 642 +/- 118.4 pg/ml, respectively, P = 0.021), whereas TNF-alpha production showed little difference between the two groups (710.1 +/- 56.4 vs 542.4 +/- 71.1 pg/ml, respectively, P = 0.149). Our results demonstrate that decreased TNF production of PBMC, which was significantly associated with TNFB*2 homozygosity, could be an important predisposing factor of lupus nephritis in Koreans.

Reproductive toxicity of 2-bromopropane in Sprague Dawley rats

OBJECTIVES

In an effort to clarify the mass intoxication of workers at an electronic company in Korea, the possible causative chemical for reproductive toxicity, 2-bromopropane (2BP), was investigated.

METHODS

2BP was tested through the use of repeated dose experiments among male Sprague Dawley rats. Ten rats were assigned to each treatment group. Vehicle control olive oil and 2BP concentrations of 125 mg/kg, 250 mg/kg, and 500 mg/kg were injected into the intraperitoneum on 28 consecutive days.

RESULTS

The rats showed significant decreases in body weight depending on the 2BP dose. The right and left testes showed typical weight loss depending on the dose of 2BP. The red blood cells, hemoglobin, and hematocrit showed some degree of decline with the high dose. The amount of hemoglobin, the mean platelet volume, the number of white blood cells, and the number of lymphocytes decreased significantly with the high dose, while the number of granulocytes and monocytes had a tendency to decrease depending on the dose of 2BP. The histopathology of the testes treated with the middle and high 2BP dose showed a typical patch appearance with severely depleted atrophic tubules, exhibiting germ cell necrosis of spermatogonia and spermatocytes in the seminiferous tubules. Leydig cell hyperplasia or hypertrophy in the interstitial tissue was also noticeable. The epididymis showed some degree of atrophy with vacuolization of the epididymal epithelium.

CONCLUSIONS

The testes are the main target organs tested for 2BP toxicity. 2BP also affect the hematopoietic system and thus induces leukopenia and normocytic anemia. Besides the reproductive organs and the hematopoietic system, no significant toxicity has been found.

Paget bone disease involving young adults in 3 generations of a Korean family

Although the etiology of Paget bone disease (PBD) is unknown, increasing evidence implicates a "slow virus" infection of the skeleton, perhaps in genetically predisposed individuals. PBD is rare in Asia. We describe a Korean family with PBD. The propositus noticed bowed limbs at approximately 25 years of age. Radiologic studies made when he was 55 years old revealed essentially panostotic PBD. Serum alkaline phosphatase (ALP) activity and osteocalcin (OC) levels were markedly elevated. An iliac crest specimen showed classic histopathologic changes of PBD. Additionally, palpable swellings were first observed at age 45 years at his occiput, pubic ramus, ileum, and facial bones. They contained numerous multinucleated cells and were originally diagnosed as giant cell tumors. However, we found that, like osteoclasts, these cells expressed considerable tartrate-resistant acid phosphatase activity. These "extraskeletal osteoclastomas" resolved rapidly with dexamethasone treatment. Two daughters, 20- and 24-years-of-age, were discovered by study of his 5 children to have elevated serum ALP activity and OC levels and widespread PBD. Both women, however, are without palpable masses and are asymptomatic. The propositus' father, who died at age 55 years, had similar skeletal deformities beginning at age 20 years, but was not examined. Leukocytopenia was found in the 3 living family members with PBD. There was no evidence for linkage of the PBD to HLA loci. The condition appears to be transmitted as an autosomal dominant trait and is manifest in young adult life. Multicentric extraskeletal osteoclastomas with remarkable sensitivity to dexamethasone treatment appear to be another unusual feature of this family's disorder. In this family, the stimulus for PBD is so great that the PBD is apparent at an early age, affects essentially the entire skeleton, and leads to the formation or extension of osteoclast-like cells into nonosseous tissues (extraskeletal osteoclastomas). This 3-generation kindred in Korea, where PBD is rare, shows a strong clustering of PBD compatible with autosomal dominant inheritance. Leukocytopenia appears to distinguish affected family members, but any role for this abnormality in the pathogenesis of PBD is unclear. Our findings support a heritable diathesis for PBD, perhaps mediated by an immune deficiency.

The impact of HLA-DRB1*0405 on disease severity in Korean patients with seropositive rheumatoid arthritis

Many reports have described HLA-DRB1 genes as having an influence on disease severity and susceptibility in rheumatoid arthritis (RA). Studies were undertaken to define the effect of RA-associated alleles on disease severity in Korean patients with seropositive RA. The results indicate that the most common RA susceptibility allele, HLA-DRB1*0405, is significantly associated with bony erosion, joint deformity and extra-articular manifestations. However, RA-associated alleles in Koreans have less effect on nodular disease than in Caucasians. This suggests that the presence of RA-associated alleles, especially HLA-DRB1*0405, seems to be a prognostic marker for severe erosive disease in Koreans.

Effects of 2-bromopropane on the female reproductive function in Sprague-Dawley rats

2-Bromopropane (2BP) has been implicated to be the reason for the mass intoxication of workers at an electronic company in Korea. A case series study indicated that 2BP was the possible causative chemical for reproductive toxicity, causing severe anemia accompanied by amenorrhea among female workers, and azoospermia or oligospermia among male workers. To clarify the effect of 2BP on the female reproductive function, repeated doses of 2BP were tested on female Sprague-Dawley rats for 21 days. Ten rats were assigned to each treatment group. The rats were maintained in a 12 hr: 12 hr light-dark cycle and vaginal smears were monitored daily for 3 cycles. After the rats had completed 3 estrous cycles, vehicle control olive oil, 300 mg, 600 mg, and 900 mg/kg of 2BP were injected into intraperitoneum for 14 days. The female rats were then mated with male rats on a 1:1 ratio basis. The treatment continued for an additional 7 days. Rats treated with 2BP experienced a significant decrease in body weight gain depending on the dose of 2BP. The estrous cycles of the rats continued at a normal duration of time before the initiation of treatment, showing 4.32 days for the control group, 4.79 days for the low dose, 4.63 days for the middle dose, and 4.75 days of estrous cycle for the high dose group. 2BP treatment, however, induced a significant delay of the estrous cycle in the high dose treated group, showing 11.1 +/- 3.82 days of the estrous cycle. 2BP decreased the fertility and tended to decrease in the number of pups born, depending on the dose. A 900 mg/kg treatment of 2BP decreased ovarian weight, but 2BP did not affect the length of gestation. Our results indicated that 2BP seemed to be the causative agent for amenorrhea observed in female workers.

Serum and urine soluble HLA class I antigen concentrations are increased in patients with hemorrhagic fever with renal syndrome

OBJECTIVES

In order to evaluate the association between the Hantaan virus-induced cellular-immune response and clinical severity in patients with hemorrhagic fever with renal syndrome (HFRS).

METHODS

We serially measured the serum (n = 16) and urine (n = 6) concentrations of soluble HLA class 1 antigen (sHLA-l) and clinical powameters in patients with HFRS.

RESULTS

Serum sHLA-I concentrations in patients with HFRS were significantly higher than those in controls throughout all clinical phases (p < 0.01). The highly elevated Serum sHLA-I concentrations peaked in the oliguric phase and declined gradually through the phases of HFRS. Serum sHLA-l concentrations in patients with hypotensive episode were higher than in those without the episode (5,85 +/-2,184 vs. 2,389 +/- 860 ng/ml in oliguric phase, 4.11 +/- 1,952 vs. 1,502 +/- 592 ng/ml in diuretic phase, p < 0.05), and serum sHLA-l levels showed a significant correlation with blood WBC count (r = 0.75 in the febrile and hypotensive phase, p < 0.01) and serum creatinine concentrations (r = 0.64 in the oliguric phase, p < 0.01), respectively, Urine sHLA-I levels in the oliguric phase were significantly higher than those in the diuretic phase (390 +/- 155 vs. 214 +/- 45 ng/mg Cr, p < 0.05) and urine sHLA-I levels are associated with severe illness in patients with HFRS. The higher serum sHLA-I are associated with severe illness in patients with HFRS. The persistent elevation of serum sHLA-I during all phases of HFRS might be related to increased production due to prolonged cellular immunologic stimulation by the Hantaan virus rather than decreased excretion of sHLA-I through the kidney.

CONCLUSION

We suggest that the serum and urine sHLA-I concentrations can be used as a stable and objective parameter for monitoring clinical severity and renal dysfunction in patients with HFRS.