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Biomedical subjects

J B Lee

Publications and source records attributed to J B Lee.

At least 19 recordsLinked to original sources
PubMed2001

A case of porphyria cutanea tarda in association with idiopathic myelofibrosis and CREST syndrome.

We report a 56-year-old Korean woman with porphyria cutanea tarda (PCT), showing multiple scarring bullae and hypertrichosis on sun-exposed areas of skin with postinflammatory hyperpigmentation. Sclerodermoid changes were also found on both hands, the face and neck. The patient had suffered from CREST syndrome, manifesting with Raynaud's phenomenon and sclerodactyly, for more than 15 years. Anticentromere antibody was positive. She had presented with splenomegaly 3 years before the development of PCT, and was diagnosed as having idiopathic myelofibrosis, based on bone marrow biopsy. In summary, she had had CREST syndrome for 15 years and later developed idiopathic myelofibrosis and PCT. This is the first reported case of PCT in association with idiopathic myelofibrosis and CREST syndrome.

CREST Syndrome↗
PubMed2001

Multicentric reticulohistiocytosis with neurofibroma-like nodules.

We describe a patient with multicentric reticulohistiocytosis (MR), who presented with 2 different clinical types of lesions. Some were characteristic for MR in that they were deeply set, small, firm papules. Many others were larger, soft, and even sessile, like neurofibromas. Histopathologic features of both types of lesions revealed MR. To our knowledge, this is the first report of lesions of MR mimicking neurofibromas.

Adrenal Cortex Hormones↗
PubMed2001

Effects of structural modification of calcium spirulan, a sulfated polysaccharide from Spirulina platensis, on antiviral activity.

Calcium ion binding with the anionic part of a molecule was replaced with various metal cations and their inhibitory effects on the replication of herpes simplex virus type 1 were evaluated. Replacement of calcium ion with sodium and potassium ions maintained the antiviral activity while divalent and trivalent metal cations reduced the activity. Depolymerization of sodium spirulan with hydrogen peroxide decreased in antiviral activity as its molecular weight decreased.

Antiviral Agents↗
PubMed2000

Activation of heparin cofactor II by calcium spirulan.

Heparin cofactor II (HCII) is a plasma serine protease inhibitor whose ability to inhibit alpha-thrombin is accelerated by a variety of sulfated polysaccharides in addition to heparin and dermatan sulfate. Previous investigations have indicated that calcium spirulan (Ca-SP), a novel sulfated polysaccharide, enhanced the rate of inhibition of alpha-thrombin by HCII. In this study, we investigated the mechanism of the activation of HCII by Ca-SP. Interestingly, in the presence of Ca-SP, an N-terminal deletion mutant of HCII (rHCII-Delta74) inhibited alpha-thrombin, as native recombinant HCII (native rHCII) did. The second-order rate constant for the inhibition of alpha-thrombin by rHCII-Delta74 was 2.0 x 10(8) M(-1) min(-1) in the presence of 50 microgram/ml Ca-SP and 10, 000-fold higher than in the absence of Ca-SP. The rates of native rHCII and rHCII-Delta74 for the inhibition of gamma-thrombin were increased only 80- and 120-fold, respectively. Our results suggested that the anion-binding exosite I of alpha-thrombin was essential for the rapid inhibition reaction by HCII in the presence of Ca-SP and that the N-terminal acidic domain of HCII was not required. Therefore, we proposed a mechanism by which HCII was activated allosterically by Ca-SP and could interact with the anion-binding exosite I of thrombin not through the N-terminal acidic domain of HCII. The Arg(103) --> Leu mutant bound to Ca-SP-Toyopearl with normal affinity and inhibited alpha-thrombin in a manner similar to native rHCII. These results indicate that Arg(103) in HCII molecule is not critical for the interaction with Ca-SP.

Binding Sites↗
PubMed2000

Treatment of Bowen's disease with a specially designed radioactive skin patch.

Bowen's disease can be treated by various methods, including surgical excision, cryosurgery, laser ablation, curettage, Mohs' microsurgery and ionizing radiation. Radiotherapy has been a useful therapeutic modality in the treatment of Bowen's disease and other skin cancers in areas which are difficult to excise, especially the central areas of the face, including eyelids, nose and lips. To overcome some of the disadvantages of external radiotherapy, a specially designed skin patch coated with high-energy beta-emitter holmium-166 was made for topical application at our institute. Twenty-nine sites of Bowen's disease in eight patients, confirmed by skin biopsy, were treated with 166Ho patches. The patches were applied to the surface of skin cancers for 30-60 min for a total radiation dose of 35 Gy (3500 rads). One to two weeks after application of the 166Ho patch, desquamation, erythema or erosion developed in treated sites, but these acute radiation reactions healed gradually with epithelial regeneration, and they showed good functional and cosmetic results without any complications. Follow-up biopsies were performed 1-5 months after 166Ho patch therapy, and they did not show any signs of Bowen's disease. One to two years after treatment with 166Ho skin patches, there were no recurrences of Bowen's diseases and no late complications. The 166Ho patch is an effective and convenient alternative method for the treatment of Bowen's disease that yields good cosmetic and functional results.

Aged↗
PubMed2000

Androgen receptor gene mutation identified by PCR-SSCP and sequencing in 4 patients with complete androgen insensitivity syndrome.

To study the genetic defect of the human androgen receptor (hAR) gene in the complete androgen insensitivity syndrome (CAIS), we amplified each of the eight exons by PCR in genomic DNA extracted from the paraffin blocks of the resected gonads. We analyzed using SSCP, and directly sequenced the abnormally shifted bands. Mutations were found in 4 cases of CAIS. Patient 1 carried a point mutation; a G to A transition in exon 7 resulted in a change from arginine to glutamine at codon 831. Patient 2 carried a point mutation; a C to T transition in exon 7 resulted in a change from arginine to stop at codon 831. Patient 3 carried a point mutation and deletion in exon 7. A point mutation was an A to G transition that caused a glutamine to be substituted for the asparagine present at codon 819. A deletion of a G at codon 820 resulted in a frameshift and consequently in the introduction of a premature stop at codon 821. Patient 4 carried a mutation in 5' splice donor site of intron 7; a G to T transition might have caused an abnormal splicing of the exon 7. All of the mutations were found in exon 7. These mutations of hAR gene might be related to the pathogenesis of CAIS.

Adolescent↗
PubMed2000

Comparison of tear secretion and tear film instability after photorefractive keratectomy and laser in situ keratomileusis.

PURPOSE: To evaluate and compare tear secretion and tear film instability following photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK). SETTING: Department of Ophthalmology, Yonsei University School of Medicine, Seoul, Korea. METHODS: In a prospective study, 36 eyes (21 patients) had PRK and 39 eyes (25 patients) had LASIK to correct myopia. Tear secretion and tear film instability were tested preoperatively and 3 and 6 months postoperatively using Schirmer test values, tear breakup time (BUT) scores, and tear osmolarity. RESULTS: Six months after surgery, the change in Schirmer test values from preoperative levels was -14.57% +/- 6.39% (SD) in the PRK eyes and -23.40% +/- 5.94% in the LASIK eyes and the change in BUT scores, -12.54% +/- 8.28% and -18.79% +/- 13.01%, respectively. The change in tear osmolarity was 14.95% +/- 6.46% and 35.63% +/- 8.51%, respectively. CONCLUSIONS: The decrease in tear secretion was greater after LASIK than after PRK at 6 months. Proper treatment of dry eye is required after LASIK and PRK, particularly in the LASIK postoperative period.

Adult↗
PubMed2000

Peroxiredoxin is ubiquitously expressed in rat skin: isotype-specific expression in the epidermis and hair follicle.

Peroxiredoxins are a family of peroxidases that are ubiquitously and abundantly expressed in mammalian tissues; however, comparatively less is known about their expression in the skin. In this study, we examined the expression of three isotypes of peroxiredoxins (I-III) in rat skin. Western blot analyses showed strong expression of peroxiredoxins I-III in the epidermis and dermis of intact skin. Additionally, they were expressed in cultured rat keratinocytes and fibroblasts. Confocal image analyses revealed that peroxiredoxin II was present in the cytoplasm as a diffuse, reticulated pattern. In immunohistochemical staining of rat skin, peroxiredoxin expression was mainly localized to the epidermis, hair follicles, and sebaceous glands. In the epidermis, peroxiredoxins I and II were expressed in all layers with a gradient of increasing expression to the granular layer. In contrast, peroxiredoxin III was expressed in all layers with a gradient of expression decreasing to the granular layer. In the hair follicle, peroxiredoxins I-III were mainly expressed in the outer root sheath, except peroxiredoxin II, which was strongly expressed in the inner root sheath. In situ hybridization showed that mRNA expression was commensurate with the level of protein. Ultraviolet B radiation increased peroxiredoxin II expression in rat skin within 15 min after irradiation. From this study we conclude that peroxiredoxin isoforms are ubiquitously expressed in rat skin, and expression of at least peroxiredoxin II can be regulated by ultraviolet irradiation as a peroxidase in the skin. J Invest Dermatol 115:1108-1114 2000

Animals↗
PubMed2000

A case of congenital inverse Duane's retraction syndrome.

Inverse Duane's retraction syndrome is very uncommon. Congenital cases are even more unusual. A 6-year-old girl with convergent squint along with severe restriction on abduction is described. On attempted abduction, a narrowing of the palpebral fissure, upshoot and retraction of the eyeball were observed. Brain and orbit MRI demonstrated no intracranial or intraorbital mass, fracture, or entrapment of the medial rectus. Forced duction test was strongly positive. The primary lesion was found to be a tight medial rectus with shortening and soft tissue contracture. Surgical tenotomy of the medial rectus led to successful postoperative motility, but some limitation at full adduction and abduction persisted. This is a case reported with congenital medial rectus shortening, suggesting that this condition may be one of the etiologies of the rare inverse Duane's retraction syndrome.

Child↗
PubMed2000

Ocular deviation after unilateral laser in situ keratomileusis.

Laser keratomileusis and excimer laser photorefractive keratectomy in situ are widely used therapies for treating myopia. The corrections of refractive error by glasses or contact lens result in a relatively equal refractive correction on both eyes. However, refractive surgery on a single eye can cause a focus disparity between both eyes and may result in the impairment of fusion leading to strabismus. This article aims to report a case where diplopia and esotropia occurred 1 month after laser keratomileusis (LASIK) in situ for the correction of myopia.

Adult↗
PubMed2000

Virulent Treponema pallidum 47 kDa antigen regulates the expression of cell adhesion molecules and binding of T-lymphocytes to cultured human dermal microvascular endothelial cells.

Perivasculitis and endothelial cell abnormalities are prominent histopathologic features of syphilis. Various cutaneous lesions are the main clinical features of syphilis. We examined whether Treponema pallidum 47 kDa antigen regulates the expression of cell adhesion molecules on human dermal microvascular endothelial cells (HDMEC) and the regulation of T-lymphocytes binding to HDMEC. Using immunofluorescence flow cytometry and enzyme-linked immunosorbent assay (ELISA), we demonstrated that T. pallidum upregulated the expression of adhesion molecules, including intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and E-selectin. The 47 kDa antigen of T. pallidum also activated endothelium as measured by the upregulation of the expression of adhesion molecules on HDMEC, and it also promoted an increased adherence of T-lymphocytes to HDMEC. The expressions of ICAM-1 and VCAM-1 on HDMEC and the adherence of T-lymphocytes to HDMEC were inhibited by treatment with anti-TNF-alpha antibody or anti-IL-1alpha antibody. These results show that T. pallidum or T. pallidum-specific 47 kDa antigen are capable of stimulating HDMEC to increase the expression of ICAM-1, VCAM-1 and E-selectin and thereby, promote the adherence of T-lymphocytes. The whole process may play an important role in the immunopathogenesis of syphilis and it is likely that TNF-alpha and IL-1alpha are involved.

Antigens, Bacterial↗
PubMed2000

Evaluation of 11C-colchicine for PET imaging of multiple drug resistance.

UNLABELLED: Overexpression of P-glycoprotein (P-gp) can confer multiple drug resistance (MDR) phenotype on cancer cells and tumors by reducing intracellular accumulation of various cytotoxic agents. Early diagnosis of MDR in the clinic will serve to improve the efficacy of chemotherapeutic intervention and the quality of life of patients. In this article we describe use of a positron-emitting MDR tracer, 11C-colchicine (CHC), to evaluate MDR by PET imaging. Unlike existing MDR tracers such as 99mTc-sestamibi, this compound is electroneutral, with biodistribution not affected by perturbations of membrane potential. METHODS: In vitro studies showed that resistance to CHC is correlated to resistance to Taxol (paclitaxel). The results of biodistribution experiments were found to be consistent with previously reported experiments with CHC labeled with other isotopes. On the basis of in vitro experiments with a series of drug-resistant variants of the human neuroblastoma BE (2)-C cell line, a mathematic model of 11C-CHC distribution in tumors was formulated. Dynamic PET 11C-CHC imaging experiments were performed with nude rats xenografted with the BE (2)-C-sensitive and -resistant strains. Each scan was accompanied by a transmissions scan and a static FDG scan. These scans allowed improved image localization. RESULTS: We observed an approximately 2-fold difference between 11C-CHC accumulation in sensitive and resistant tumors. Imaging data were analyzed using the mathematic model, and various parameters characterizing resistance could be identified and estimated. In particular, the parameter r, proportional to the level of resistance of the tumors, was obtained. We showed that the ratio of these r parameters determined from the sensitive and resistant tumors was identical to the ratio of CHC accumulation in the corresponding sensitive and resistant cell lines used for xenografting. CONCLUSION: These in vivo experiments provided additional evidence for the indirect effect of P-gp action on CHC-to-tubulin binding, which in turn determines CHC uptake in tumors. The significance of these findings and future plans is discussed.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

Modified Kestenbaum surgery for correction of abnormal head posture in infantile nystagmus: outcome in 63 patients with graded augmentaton.

PURPOSE: To analyze the surgical effect of modified Kestenbaum surgery and show how to determine the amount of appropriate augmentation for correction of abnormal head posture in infantile nystagmus. METHODS: We reviewed the records of 63 patients with infantile nystagmus who required surgery for a significant face turn and who were followed for at least five months after surgery. Group 1, consisting of 29 patients, received Parks' modification of the standard Kestenbaum procedure (the 5-6-7-8 mm procedure); Group 2, 32 patients, received a 20% augmentation of the original Parks recommendation; and Group 3, 2 patients, received a 30% augmentation of the original Parks procedure. Pre-and postoperative measurements with electro-oculography (EOG) using Nicolet Compact Four/CA 2000 were made. RESULTS: The average preoperative face turn in the 63 patients with horizontal nystagmus was 31.9 degrees with an average postoperative face turn of 5.2 degrees. The average net change in face turn was 26.7 degrees. The average duration of time from surgery to final examination was thirteen months. Fifty-six out of 63 patients (89%) achieved a straight head position or a residual face turn of 10 degrees or less. CONCLUSION: A Parks' modified Kestenbaum procedure, with appropriate graded augmentation up to 30% is effective for the correction of abnormal head posture in infantile nystagmus without the need for larger augmentations.

Adolescent↗