Bronchiolitis obliterans organizing pneumonia in Korea

An analysis of the clinical features in 23 cases of bronchiolitis obliterans organizing pneumonia (BOOP) in Korea is presented. Six were men and 17 were female, with a male-to-female ratio of 1:2.4. Idiopathic BOOP was present in 18 of these patients, connective tissue disease-associated BOOP in five and all of them were females. The most frequent symptoms were dyspnoea and coughing in both groups; and crackles were the most prominent physical findings. Leukocytosis was observed in seven of the idiopathic BOOP group and all in the connective tissue disease-associated BOOP group. In most cases, FVC, FEV 1, diffusing capacity and arterial O2 pressure were reduced. In roentgenographic study, patchy air space consolidation was the major finding and subpleural predominance was observed in the majority of patients in both groups. Migration of lesions were identified in only two patients with idiopathic BOOP. Steroid treatment was effective in all of idiopathic BOOP. In contrast to previous reports, an analysis of the 23 Korean BOOP patients showed several interesting points. First, a female predominance was observed. Second, migration of lesion was rare. Third, it did not show any different prognosis in patients with reticular pattern on roentgenogram compared with patients with patchy air space consolidation on roentgenogram. Whether these differences were due to ethnic or environmental factors is to be determined.

Telomerase activity in lung cancer cell lines and tissues

Using TRAP assay, we studied the activity of the telomerase in the lung cancer cell lines, and lung cancer and normal tissues in which expression appears to be related to the immortality of cancer cells. All the human lung cancer cell lines and the majority of human lung cancer tissues (78%) expressed telomerase activity, but this was undetectable in normal human lung tissues. Positivity for telomerase activity in lung cancer cell lines was higher than in lung cancer tissues; this result implies the expression of telomerase activity may play a crucial role in the development or progression of lung cancer, and also suggests that improved method of detection may lead to the higher positivity for telomerase activity in primary lung cancer tissues. To determine whether there is a definite causal relationship between telomerase and cancer, and to develop new anti-cancer agents which inhibit telomerase, further study is needed.

Isolation and characterization of beta-galactoside specific lectin from Korean mistletoe (Viscum album var. coloratum) with lactose-BSA-sepharose 4B and changes of lectin conformation

Lectins and its A- and B-chains from Korean mistletoe (Viscum album var. coloratum) were isolated by affinity chromatography on the Sepharose 4B modified by lactose-BSA conjugate synthesized by reductive amination of ligand (lactose) to epsilon-amino groups of lysine residues of spacer (BSA) after reduction by NaCNBH3. The lactose-BSA conjugate was coupled to Sepharose 4B activated by cyanogen bromide. The molecular weight determined by SDS-PAGE were a 31 kD of A-chain and a 35 kD of B-chain. Amino acid analysis and N-terminal sequencing were performed. The effects of pH, temperature and guanidine chloride on the conformation of the lectin were investigated by measuring its intrinsic fluorescence and compared with its hemagglutinating activities. Blue shift was detected on the acidic pH and there was a close relationship between activities and conformation of the lectin. Under denaturing conditions, the tryptophan emission profile of lectin showed typical denaturational red shift which also correspond to the conformations and activity of lectin.

Genetic instability of microsatellite sequences in non-small cell lung cancers

To evaluate the frequency and pattern of microsatellite instability in NSCLCs, we examined 36 cases of resected NSCLC. The mean age of the patients was 59.9+/-8.4 years. There were 19 cases of squamous cell carcinoma, 15 of adenocarcinoma and two of large cell carcinoma. We observed microsatellite instability at one or more loci in 13 (36%) of 36 tumors analyzed, and this instability ranged from six tumors showing instability in only a single microsatellite to three tumors that had alterations in three of four tested microsatellites. The microsatellite that showed instability most frequently in these tumors was D3S1340 (31%). Microsatellite instability was found in five (26%) of 19 squamous cell carcinomas, six (40%) of 15 adenocarcinomas, and in both large cell carcinomas tested. We found microsatellite instability in four (24%) of 17 cancers at stage I, in one (17%) of six at stage II, in eight (73%) of eleven at stage IIIa, and in neither at stage IIIb. In conclusion, microsatellite instability was noted in at least one third of non-small cell lung cancers, suggesting its possible role in cancer development.

Aerobic microbial degradation of aromatic sulfur-containing compounds and effect of chemical structures

Batch data of aerobic microbial degradation rate constants Kb of phenylthio, phenylsulfinyl and phenylsulfonyl acetates have been determined, and the qualitative relationships between their Kb and chemical structures were analyzed. The phenylthio acetates were most subject to microbial transformation, followed by the phenylsulfonyl acetates. The compounds with a methoxy group were easier degraded than those with a isopropoxy group. The nitro-group and chloro-group on benzene were shown to lower the biodegradability, while the nitro-group at the para-position had stronger side effect on degradation than at the ortho-position.

Bacterial expression and characterization of human secretory class V phospholipase A2

Mammalian secretory class V phospholipase A2 (PLA2) is a newly discovered PLA2 that is implicated in eicosanoid formation in inflammatory cells. As a first step towards understanding the structure, function and regulation of this PLA2, we constructed a bacterial expression vector for human secretory class V PLA2 (hV-PLA2), over-expressed and purified the protein, and determined its physical and kinetic properties. When compared with human class IIa enzyme (hIIa-PLA2), hV-PLA2 has several distinct properties. First, hV-PLA2 can catalyse the hydrolysis of phosphatidylcholine more effectively than hIIa-PLA2 by two orders of magnitude. Secondly, hV-PLA2 has much higher binding affinity and activity for compactly packed phosphatidylcholine bilayers than hIIa-PLA2. Finally, hV-PLA2 has much reduced thermal stability compared with hIIa-PLA2. These data suggest that hV-PLA2 is better suited than hIIa-PLA2 for acting on the outer cellular membrane and liberating arachidonic acid from membrane phospholipids. Also, the unusually low thermal stability of hV-PLA2 might contribute to tighter regulation of its activities in extracellular media.

Synthesis and evaluation of 5-aminosalicyl-glycine as a potential colon-specific prodrug of 5-aminosalicylic acid

As a new colon-specific prodrug of 5-aminosalicylic acid (5-ASA), 5-aminosalicyl-glycine (5-ASA-Gly) was prepared by a simple synthetic route in good yield. Apparent partition coefficients of 5-ASA-Gly were lower than those of 5-ASA, which determined in CHCl3/pH 6.8 buffer or n-octanol/pH 6.8 buffer system. Stability of 5-ASA-Gly by peptidases was investigated by incubation of 5-ASA-Gly with the homogenates of tissue and contents of stomach, proximal small intestine or distal small intestine of rats at 37 degrees C. 5-ASA was not detected, indicating that the prodrug was stable in the upper intestine. The amount of 5-ASA liberated from incubation of the prodrug in cecal or colonic contents of rats was about 65% or 27% in 8 hrs, respectively, which indicated that the prodrug activation took place more readily in the rat cecum whose bacterial counts are high like human colon. Results from in vitro experiments suggested 5-ASA-Gly as a promising candidate of a colon-specific prodrug of 5-ASA.

The reverse digital artery island flap: clinical experience in 120 fingers

Fingertip injuries represent the most common type of injuries seen in the upper extremity. Their management is functionally and aesthetically important but at the same time very controversial. The aim of this study is to report usefulness and postoperative results of reverse digital artery island flaps for fingertip reconstruction. From July of 1984 to December of 1995, 120 fingers in 110 patients with defects of the distal phalanx were reconstructed by reverse digital artery island flaps at Korea University Guro Hospital. We reviewed the medical records of our cases and analyzed them in several aspects. In 21 cases, neurorrhaphy was performed to improve sensibility. In the majority of the cases, the defect was covered primarily, whereas in 27 cases it was covered secondarily after composite graft, replantation, and so on. All the flaps survived except for one. Long-term follow-up for more than 6 months was possible in 44 fingers in 41 patients. Light touch and temperature sensation could be detected in all the evaluated flaps. The mean values of the static two-point discrimination test in sensate and insensate flaps were 6.2 and 10.2 mm, respectively. The reverse digital artery island flap is a safe and reliable procedure with a high survival rate and therefore is an excellent choice for coverage of fingertip defects.

Deprenyl and desmethylselegiline protect mesencephalic neurons from toxicity induced by glutathione depletion

Oxidative stress is thought to play an important role in the pathogenesis of Parkinson's disease (PD). Glutathione (GSH), a major cellular antioxidant, is decreased in the substantia nigra pars compacta of PD patients. The aim of the present study was to investigate whether deprenyl and its desmethyl metabolite, putative neuroprotective agents in the treatment of PD, could protect cultured rat mesencephalic neurons from cell death caused by GSH depletion due to treatment with L-buthionine-(S,R)-sulfoximine (BSO). BSO (10 microM) caused extensive cell death after 48 hr, as demonstrated by disruption of cellular integrity and release of lactate dehydrogenase into the culture medium. Both deprenyl and desmethylselegiline, at concentrations of 5 and 50 microM, significantly protected dopaminergic neurons from toxicity without preventing the BSO-induced loss in GSH. Protection was not associated with monoamine oxidase type B inhibition in that pargyline, a potent MAO inhibitor, was ineffective and pretreatment with pargyline did not prevent the protective effects of deprenyl. Protection was not associated with inhibition of dopamine uptake by deprenyl because the dopamine uptake inhibitor mazindol did not diminish BSO toxicity. The antioxidant ascorbic acid (200 microM) also protected against BSO-induced cell death, suggesting that oxidative events were involved. This study demonstrates that deprenyl and its desmethyl metabolite can diminish cell death associated with GSH depletion.

Mapping the interfacial binding surface of human secretory group IIa phospholipase A2

Human secretory group IIa phospholipase A2 (hIIa-PLA2) contains a large number of prominent cationic patches on its molecular surface and has exceptionally high affinity for anionic surfaces, including anionic membranes. To identify the cationic amino acid residues that support binding of hIIa-PLA2 to anionic membranes, we have performed extensive site-directed mutagenesis of this protein and measured vesicle binding and interfacial kinetic properties of the mutants using polymerized liposomes and nonpolymerized anionic vesicles. Unlike other secretory PLA2s, which have a few cationic residues that support binding of enzyme to anionic membranes, interfacial binding of hIIa-PLA2 is driven in part by electrostatic interactions involving a number of cationic residues forming patches on the putative interfacial binding surface. Among these residues, the amino-terminal patch composed of Arg-7, Lys-10, and Lys-16 makes the most significant contribution to interfacial adsorption, and this is supplemented by contributions from other patches, most notably Lys-74/Lys-87/Arg-92 and Lys-124/Arg-127. For these mutants, complete vesicle binding occurs in the presence of high vesicle concentrations, and under these conditions the mutants display specific activities comparable to that of wild-type enzyme. These studies indicate that electrostatic interactions between surface lysine and arginine residues and the interface contribute to interfacial binding of hIIa-PLA2 to anionic vesicles and that cationic residues closest to the opening of the active-site slot make the most important interactions with the membrane. However, because the wild type binds extremely tightly to anionic vesicles, it was not possible to exactly determine what fraction of the total interfacial binding energy is due to electrostatics.

Oleanolic acid and ursolic acid stabilize liposomal membranes

The effects of oleanolic acid (OA) and ursolic acid (UA) on the fluidity and stability of dipalmitoyl phosphatidylcholine (DPPC) liposomal membrane were monitored by measuring the fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene labeled in the liposomal membrane and the leakage of calcein from the probe-encapsulated liposomes. The experiments with the liposomes made of DPPC and OA or UA showed that OA and UA exhibited a moderate fluidity-modulating effect for the liquid-crystalline liposomal membrane, and a strong condensing effect for both crystalline and liquid-crystalline liposomal membranes. Their effects were comparable to those of cholesterol. These results suggest that their fluidity-modulating and condensing effects might have some implications in their biological functions.

Bacterial expression and characterization of human pancreatic phospholipase A2

Mammalian pancreatic phospholipases A2 (PLA2) have recently been implicated in cell surface receptor-mediated inflammation. As a first step toward understanding how human pancreatic PLA2 (hp-PLA2) interacts with membranes and other biological targets including cell-surface receptors, we constructed its bacterial expression vector which can be used for the mutagenesis and protein over-expression. The expression vector (pSH-hp) was constructed using a synthetic hp-PLA2 gene whose transcription is controlled by T7 promoter. hp-PLA2 was expressed as a mature protein in high concentration in Escherichia coli cells and formed inclusion body. The solubilization of inclusion body protein followed by the refolding and purification produced ca. 5 mg of pure protein from one liter of growth medium. Kinetic studies of recombinant human, bovine and porcine pancreatic PLA2s using polymerized mixed liposomes and micelles as substrates showed that despite their highly homologous structures these mammalian pancreatic PLA2s have distinct phospholipid head group specificity and different activity toward various lipid substrates.

Isoniazid resistance and the point mutation of codon 463 of katG gene of Mycobacterium tuberculosis

It has long been known that almost all isoniazid (INH) resistant mycobacteria lose the catalase and peroxidase activities along with reduced or no virulence for guinea pigs. Recently resistance to INH has become known to be associated with mutations of katG gene encoding the HPI (Hydroperoxidase I) type catalase and peroxidase. Among these mutations, the point mutation of codon 463 of katG gene is found frequently, and is suggested as being associated with INH resistance. Therefore we performed this study in order to confirm the correlation between the point mutation of codon 463 of the katG gene and INH resistance of M. tuberculosis in Korea. Fifty isolates, 32 of which were resistant to INH, and 18 of which were sensitive to INH, were selected for this study. We used PCR-SSCP and RFLP analysis to detect the point mutation of the codon 463 of katG gene and confirmed the CGG (arginine) to CTG (leucine) mutation by direct sequencing analysis. Among 32 resistant isolates, 7 isolates (22%) had the same restriction pattern compared with that of the reference strain (H37Rv), and 25 isolates (78%) showed a different restriction pattern. Among 18 sensitive isolates, 7 isolates (39%) had the same restriction pattern compared with that of H37Rv, and 11 isolates (61%) showed a different restriction pattern. These results suggest that the CGG to CTG change of codon 463 of katG gene of M. tuberculosis may be a polymorphism not related with INH resistance.

Summer-type hypersensitivity pneumonitis outside Japan: a case report and the state of the art

A 61-year-old Korean housewife developed dyspnoea, cough and weight loss in the summer of 1994. The case was diagnosed as definite summer-type hypersensitivity pneumonitis (SHP) according to the criteria proposed for hypersensitivity pneumonitis and for SHP. Her serum antibodies to Trichosporon were positive. Her symptoms were exacerbated after she returned home and Trichosporon was isolated from the patient's home, indicating Trichosporon as the causative antigen. This is the first confirmed case of SHP outside Japan. On the basis of our research in SHP to date, we propose that SHP occurs in other Asian countries and that the assay of anti-Trichosporon antibodies is useful for the diagnosis of the disease.

Structural aspects of interfacial adsorption. A crystallographic and site-directed mutagenesis study of the phospholipase A2 from the venom of Agkistrodon piscivorus piscivorus

Recent genetic and structural studies have shed considerable light on the mechanism by which secretory phospholipases A2 interact with substrate aggregates. Electrostatic forces play an essential role in optimizing interfacial catalysis. Efficient and productive adsorption of the Class I bovine pancreatic phospholipase A2 to anionic interfaces is dependent upon the presence of two nonconserved lysine residues at sequence positions 56 and 116, implying that critical components of the adsorption surface differ among enzyme species (Dua, R., Wu, S.-K., and Cho, W. (1995) J. Biol. Chem. 270, 263-268). In an effort to further characterize the protein residues involved in interfacial catalysis, we have determined the high resolution (1.7 A) x-ray structure of the Class II Asp-49 phospholipase A2 from the venom of Agkistrodon piscivorus piscivorus. Correlation of the three-dimensional coordinates with kinetic data derived from site-directed mutations near the amino terminus (E6R, K7E, K10E, K11E, and K16E) and the active site (K54E and K69Y) defines much of the interface topography. Lysine residues at sequence positions 7 and 10 mediate the adsorption of A. p. piscivorus phospholipase A2 to anionic interfaces but play little role in the enzyme's interaction with electrically neutral surfaces or in substrate binding. Compared to the native enzyme, the mutant proteins K7E and K10E demonstrate comparable (20-fold) decreases in affinity and catalysis on polymerized mixed liposomes of 1-hexadecanoyl-2-(1-pyrenedecanoyl)-sn-glycero-3-phosphocholine and 1,2-bis[12-(lipoyloxy)dodecanoyl]-sn-glycero-3-phosphoglycerol, while the double mutant, K7E/K10E, shows a more dramatic 500-fold decrease in catalysis and interfacial adsorption. The calculated contributions of Lys-7 and Lys-10 to the free energy of binding of A. p. piscivorus phospholipase A2 to anionic liposomes (-1.8 kcal/mol at 25 degrees C per lysine) are additive (i.e. -3.7 kcal/mol) and together represent nearly half of the total binding energy. Although both lysine side chains lie exposed at the edge of the proposed interfacial adsorption surface, they are geographically remote from the corresponding interfacial determinants for the bovine enzyme. Our results confirm that interfacial adsorption is largely driven by electrostatic forces and demonstrate that the arrangement of the critical charges (e.g. lysines) is species-specific. This variability in the topography of the adsorption surface suggests a corresponding flexibility in the orientation of the active enzyme at the substrate interface.

Inhibition of catalase in mesencephalic cultures by L-DOPA and dopamine

Catalase activity in cell cultures of fetal rat mesencephalon was decreased by 42 and 50%, respectively, after exposure to L-3,4-dihydroxyphenylalanine (L-DOPA, 100 microM) or dopamine (100 microM) for 48 h. Catalase activity was also decreased 21% by 10 microM hydroquinone. Ascorbic acid (200 microM), an agent that suppresses the autoxidation of L-DOPA and dopamine, blocked the anti-catalase effect of L-DOPA, but not that of dopamine. Inhibitors of the A and B forms of monoamine oxidase (20 microM clorgyline plus 20 microM pargyline) had no effect on the anti-catalase action of either L-DOPA or dopamine. The latter results suggest that products of the oxidative deamination of dopamine by monoamine oxidase are not involved in the suppression of catalase activity. However, autoxidation reactions of L-DOPA may play a role since ascorbate suppressed the anti-catalase effect of L-DOPA. On the contrary, the basis for the failure of ascorbate to similarly block the anti-catalase effect of dopamine is uncertain. L-DOPA and dopamine (25 microM) also inhibited crystalline catalase in solution after incubation for 1 h at neutral pH (40-50% inhibition). Inhibition was blocked by 0.45 M ethanol, indicating a need for autoxidation and the formation of compound II, which is an enzymatically inactive form of catalase. The ability to model the enzyme inhibition in purely chemical experiments indicates a probable mechanism for loss of enzymatic activity in cell cultures. Inhibition of catalase may contribute to cell damage during incubation of cultures with L-DOPA, dopamine, or other autoxidizable compounds.

Fingertip replantations: clinical evaluation of 135 digits

From July 1985 to February 1993, 135 digits in 119 patients with complete amputations at or distal to the distal interphalangeal joint (zone I for amputations distal to the nail base of zone II for amputations between the distal interphalangeal joint and the nail base) were replanted using a microsurgical technique at Korea University Guro Hospital. Because of the high social value placed on body form and function, the indication for replantation was extended to cases with severe soft-tissue injuries and attempted replantation as a routine procedure in nearly all distal amputation cases. The overall survival rate was 78 percent, with the survival rate for zone I being 70 percent and that for zone II reaching 86 percent. Even in cases with severe soft-tissue injury, the survival rate was high, with viability in avulsion injuries and crush injuries reaching 75 percent each. The most common type of vascular repair in zone I cases was revascularization of one artery only and no vein repair (87 percent). Of these cases, interpositional vein grafts were used in 65 percent. In zone II cases, the most common combination repair was one artery and one vein anastomosis (70 percent), with interpositional vein grafts for arterial anastomosis in 49 percent; most of the venous repair was feasible by the direct method (78 percent). The follow-up period ranged from 1 month to 5 years with a mean of 14.8 months; 52 patients were followed-up for more than 6 months. In 52 long-term follow-up patients, the average two-point discrimination was 8 mm. Patient satisfaction, aesthetically and functionally, was high (91 percent).

An adult case of pulmonary sling with complete tracheal ring

Pulmonary sling is a rare congenital condition in which the left pulmonary artery arises from the right pulmonary artery forming a sling around the trachea causing tracheal compression. Many cases are associated with cardiovascular and tracheo-bronchial anomalies. When combined with complete tracheal ring, it is called "ring-sling complex". The average onset of symptoms is 2 months and about half have symptoms from birth. The anomaly, if not corrected, can be fatal within the first year of life. In an adult, it is most often asymptomatic and usually found incidentally. We report an adult case who was diagnosed as pulmonary sling with complete tracheal ring by CT and bronchoscopy along with a literature review.

L-DOPA up-regulates glutathione and protects mesencephalic cultures against oxidative stress

Incubation with L-DOPA induced a rise in GSH level in cultures of fetal rat mesencephalon, mouse neuroblastoma (Neuro-2A), human neuroblastoma (SK-N-MC), pig kidney epithelial cells (LLC-PK1), and glia from newborn rat brain, but not C6 glioma cells or neuronal cultures (no glia) from the mesencephalon. The pure neuronal cultures were destroyed by incubation with L-DOPA; added ascorbic acid or superoxide dismutase protected the cells. Washout of L-DOPA after 48 h amplified the rise in GSH content in mixed cultures (neurons plus glia). Examination of structure-activity relationships for elevating GSH levels in responsive cell types revealed that autooxidizable compounds (alpha-methyl-DOPA, dopamine, apomorphine, catechol, and hydroquinone) behaved similarly to L-DOPA, whereas structural analogues that cannot undergo autooxidation (3-O-methyl-DOPA, tyrosine, 2,4-dihydroxyphenylalanine, and resorcinol) failed to elevate GSH levels. Therefore, up-regulation of GSH appears to be a response to a mild oxidative stress. When mixed mesencephalic cultures were exposed to a strong oxidant stress by incubation with tert-butyl hydroperoxide, a loss in viability was seen. Cultures pretreated with L-DOPA or hydroquinone were protected from loss of viability. However, when cultures were pretreated with both L-DOPA and ascorbate, which prevents the rise in GSH level, protection was lost, in accord with the failure to up-regulate GSH. These results show that the up-regulation of cellular GSH evoked by autooxidizable agents is associated with significant protection of cells. Glia play an essential role in the response of mesencephalic cell cultures. An ability to up-regulate GSH may serve a protective role in vivo.

Prognostic factors of patients with thymoma

OBJECTIVES

To analyze the prognostic factors influencing the survival of patients with thymoma, clinical characteristics, treatment modalities and survival of patients were evaluated. The efficacy of chemotherapy was also determined.

METHODS

Retrospective study was done on one hundred patients whose diagnosis was confirmed pathologically at Seoul National University Hospital from 1981 to 1994. The staging was carried out according to the Masaoka system. Survival rate was calculated by the Kaplan-Meier method and prognostic factors were analyzed by a multivariate analysis (Weibull model).

RESULTS

The stage of 100 patients was as follows: Stage I-50, II-6, III-27, IV A-10, IV B-7. The overall survival rates at 5 and 10 years after diagnosis were 73.1% and 58.7%, respectively. The 5-year survival differences, according to various prognostic factors, were as follows: 1) Stage: I-92.8%, II-100%, III-71.6%, IVA-25.9% and IVB-32.9% (p = 0.0029). 2) Age: < 60 years-79.5% and > or = 60 years-41.5% (p = 0.0489). 3) Extent of resection: Total patients: complete resection-87.6% and incomplete resection-50.5% (p > 0.05) Stage III: complete resection-66.7% and incomplete resection-75.5% (p > 0.05) 4) Myasthenia gravis: present-71.6% and absent-74.9% (p > 0.05) Seventeen patients were treated with a combination chemotherapy of Cyclophosphamide, Adriamycin and cisplatin(CAP). Two complete responses and seven partial responses (overall response rate of 53%) were observed with a median response duration of fourteen months. Combination chemotherapy with CAP was effective.

CONCLUSIONS

Stage and age were the independent prognostic factors in patients with thymoma. However, the presence of myasthenia gravis or the extent of resection in stage III patients was not associated with the survival time.