Estimation of intracardiac shunts in congenital heart disease. A comparison of the dy-edilution and the Fick methods.
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Biomedical subjects
Publications and source records attributed to H Kim.
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A cellulose binding domain (CBD) of an endo-beta-1,4-glucanase (Ben) from the bacterium Bacillus subtilis BSE616 was replaced with the CBD of exoglucanase I (TexI) from the fungus Trichoderma viride HK-75. The resultant hybrid enzyme Ben'-CBDTexI, comprising the catalytic domain (Ben') of Ben and the CBD (CBDTexI) of TexI, was highly expressed at 20% of the total protein in Escherichia coli. The molecular mass of the hybrid enzyme was estimated to be ca. 38 kDa by SDS-PAGE, which was in good agreement with that calculated from 305 amino acids of Ben and 42 amino acids of CBDTexI. The hybrid enzyme exhibited almost the same activity as that of the original Ben toward soluble substrates, such as cellooligosaccharides. The hybrid enzyme showed higher binding ability and hydrolysis activity toward microcrystalline cellulose (Avicel), even though the length of the CBD of TexI was four times smaller than that of Ben. The hybrid enzyme was more resistant to tryptic digestion than the original Ben. The efficient binding ability of the hybrid enzyme to Avicel permitted purification of the enzyme using an Avicel-affinity column to the extent of ca. 90% purity.
Most hepatic artery pseudoaneurysms result from trauma, blunt or penetrating, such as that caused by percutaneous transhepatic procedures. We present a case of hepatic artery pseudoaneurysm resulting from a pyogenic liver abscess, which has not been described previously, in a patient with acute leukemia receiving chemotherapy.
Previously, we reported that pooled normal human serum contained anti-IL-1 alpha autoantibodies. Further characterization studies have been undertaken with sera from individual healthy humans. Molecular exclusion chromatography demonstrated that 9 of 38 test sera contained anti-IL-1 alpha autoantibodies that specifically bound 125I-IL-1 alpha. The autoantibodies formed immune complexes composed of either one IgG or two IgG molecules bound to one 125I-IL-1 alpha molecule. The data suggest that the autoantibodies recognize at least two separate antigenic sites on IL-1 alpha. The autoantibodies neutralized IL-1 alpha induced IL-2 secretion by mouse thymocytes (EL-4 NOB-1). Further, in an in vitro competitive receptor binding assay, the autoantibodies completely blocked 125I-IL-1 alpha binding to recombinant human IL-1 receptor expressed on CHO cells. Our previous studies have established a correlation between inhibition of 125I-IL-1 alpha binding to receptor bearing cells and neutralization of IL-1 bioactivity in vitro and in vivo. These data suggest that development of anti-IL-1 alpha autoantibodies may play a significant role in modulating the effects of high local or systemic concentrations of IL-1 alpha.
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Drug developments in the vitamin D field have continued to focus on structure-function studies of analogs produced by chemically modifying the structure of 1alpha,25-dihydroxyvitamin D(3) (1,25-D3) and its metabolites. Direct structural information gleaned from X-ray crystallographic or NMR studies regarding the ligand-receptor complex and other guest-host systems, which are likely involved in initiating biologic responses, also offers potential insight into drug design. Evidence has accrued suggesting that topologically different conformers of 1,25-D3 may bind to proteins in different ways, including the induction of different conformations of protein. This paper concerns our progress on the chemical synthesis of analogs (e.g. ansa-steroids, suprasterols, vinylallenes and other analogs) conformationally locked or at least rotationally restricted to mimic higher energy conformers of 1,25-D3.
We investigated the effects of the aqueous extract of Solanum lyratum THUNB. (Solanaceae) (SLAE) on the anaphylactic reactions. SLAE inhibited compound 48/80-induced anaphylactic shock 100% with a dose of 1.0 mg/g body weight (BW). When SLAE was pretreated at concentration ranging from 0.0001-1.0 mg/g BW, the serum histamine levels were reduced in a dose-dependent manner. Passive cutaneous anaphylaxis also inhibited to 69.3% by oral administration of SLAE (0.05 mg/g BW). Moreover, SLAE dose-dependently inhibited the histamine release from the rat peritoneal mast cells (RPMC) by compound 48/80. The level of cAMP in RPMC, when SLAE was added, significantly increased compared with that of normal control. These results indicate that SLAE possess strong antianaphylactic activity.
We investigated whether an aqueous extract of Asparagus cochinchinensis Merrill (Liliaceae) roots (ACAE) inhibits secretion of tumor necrosis factor-alpha (TNF-alpha) from primary cultures of mouse astrocytes. ACAE dose-dependently inhibited the TNF-alpha secretion by astrocytes stimulated with substance P (SP) and lipopolysaccharide (LPS). IL-1 has been shown to elevate TNF-alpha secretion from LPS-stimulated astrocytes while having no effect on astrocytes in the absence of LPS. We therefore investigated whether IL-1 mediated inhibition of TNF-alpha secretion from astrocytes by ACAE. Treatment of ACAE to astrocytes stimulated with both LPS and SP decreased IL-1 secretion. Moreover, incubation of astrocytes with IL-1 antibody abolished the synergistic cooperative effect of LPS and SP. These results suggest that ACAE may inhibit TNF-alpha secretion by inhibiting IL-1 secretion and that ACAE has a antiinflammatory activity in the central nervous system.
We investigated the effect of aqueous extract of Rehmannia glutinosa steamed root (RGAE) on the allergic reactions in vivo and in vitro. RGAE dose-dependently inhibited systemic allergic reaction induced by compound 48/80. When RGAE was pre-treated at the same concentrations with systemic allergic reaction test, the plasma histamine levels were reduced in a dose-dependent manner. RGAE dose-dependently inhibited skin allergic reaction activated by anti-dinitrophenyl (DNP) IgE. RGAE also dose-dependently inhibited the histamine release from the rat peritoneal mast cells (RPMC) by compound 48/80 or anti-DNP IgE. Moreover, RGAE had significant inhibitory effect on anti-DNP IgE-induced tumor necrosis factor-alpha production of RPMC. These results indicate that RGAE may be beneficial in the regulation of immediate type allergic reaction.
Distribution of vitronectin (VN) receptors on a living murine osteoblastic cell was successfully measured by atomic force microscopy (AFM). First, the distribution of the integrin beta(5) subunit which constitutes a part of the VN receptor on the cell was confirmed by conventional immunohistochemistry after fixing the cell. To visualize the distribution of the receptor on a living cell by an independent and potentially a more quantitative method, the AFM was used with a microbead attached to the cantilever tip to increase the area of contact and VN was immobilized on the microbead. Force measurements were then performed over a large area of a living murine osteoblastic cell using the microbead covered with VN.
To evaluate the health effects of role overload, the relationship between multiple role (i.e., worker, spouse, caretaker) strain and current cigarette smoking was examined. A cross-sectional survey of women veterans, aged 36-85 years, was performed measuring home and job strain and health behaviors. Of the 275 women who rated both their work and home strains, 25% (n = 69) currently smoke cigarettes. Higher work strain, but not higher home strain, was associated with smoking adjusting for age, education, income, weight, and marital status. A stressful work environment may trigger persistent smoking and should be addressed during smoking cessation counseling.
BACKGROUND: Restenosis is a consequence of both neointimal hyperplasia and vessel remodeling. Prior studies have shown that intracoronary radiation (IR) prevents neointima accumulation, but its contribution to vessel remodeling is unknown. The purpose of this study was to evaluate the effect of IR on differential vascular remodeling after balloon angioplasty in porcine coronary arteries. METHODS: A total of 20 juvenile swine (30 coronary arteries) were subjected to overstretch balloon injury (BI) followed by IR with either beta- or gamma-radiation ((90)Y or (192)Ir). After 2 weeks following treatment, serial tissue sections were perfusion fixed and stained by hematoxylin and eosin (H&E), Verhoeff von Giesson (VVG), or Masson Trichrome. Adventitial area (AA), lumen area (LA), vessel area (VA), intimal area (IA), and IA corrected for medial fracture length (IA/FL) were quantified by digital image analysis. The vessel circumference was divided into two regions containing (1) the undisrupted region (UReg) with the undisrupted arc of media and internal elastic lamina (IEL) and (2) the disrupted region (DReg) with the disrupted arc between the medial tears. Quantitative regional analysis was performed by (1) measuring the IEL to define the UReg, (2) calculating the area of the UReg with the perimeter value derived from measurement of the IEL, and (3) calculating the DReg as follows: LA+IA-UReg. Immunohistochemical smooth muscle cell alpha-actin and Masson Trichrome were quantified by digital image analysis. RESULTS: The IA/FL was significantly smaller following treatment with (90)Y or (192)Ir vs. control (P<.01). A smaller AA was obtained following IR with both beta- and gamma-sources vs. control (P<.01). The UReg calculation was smaller in the irradiated arteries as compared to control (beta: 2.3+/-0.4 mm(2), gamma: 2.1+/-0.5 mm(2), P<.01 vs. control; control: 3.6+/-0.7 mm(2)). In contrast, the DReg was increased following IR, as demonstrated by the FL and the calculated area of the injured segment (control: 2.7+/-0.5 mm(2); beta: 5.5+/-1.1 mm(2), gamma: 5.5+/-1.1 mm(2), P<.01 vs. control). Adventitial alpha-actin positive cell density (CD) was decreased after IR; however, the collagen density was similar. In contrast, the neointimal collagen density in the injured segment was significantly decreased following IR. CONCLUSION: We consider that the global arterial remodeling after IR is a heterogeneous process that includes the absence of retraction in an UReg and a positive remodeling in the DReg as shown in the porcine coronary model. These changes in adventitia and neointima appear to contribute to differential vascular remodeling caused by IR in injured vessels.
A GTP photoaffinity probe (125I-APTG) was developed that incorporated an [125I]-N-(4-azidophenyl)-2-amino-3-(4-hydroxy-3-iodophenyl)propionamide group at the gamma-position of GTP through a phosphonamide linkage. A combination of saturation and GTP protection studies (90% protection at 25 microM GTP with an apparent Kd of 5 microM) validated the use of this new probe as a satisfactory GTP mimic. This probe offered the advantage of possessing an 125I radiolabel external to the GTP moiety, in contrast to the previously reported [gamma 32P]-8-N3GTP that possessed an internal 32P radiolabel. This novel feature accommodated the purification of photolabeled peptides using a combination of ion-exclusion, gel filtration, and HPLC techniques. [125I]APTG was used to identify a peptide (beta:65-79) in the exchangeable GTP-binding domain of the beta-subunit of tubulin.
Previously, the synthesis and validation of [32P]2N3NAD+ as an active site directed photoaffinity probe for glutamate dehydrogenase (GDH) was reported (8). This report shows that 2N3NAD+ is also an effective probe for the NAD+ binding site of lactate dehydrogenase (LDH). With the appropriate photolabeling procedures and immobilized boronate column chromatography the active site peptides of GDH and LDH involved in the adenine base binding domain have been isolated and sequenced. With both GDH and LDH a single photolabeled peptide, which contained the majority of the photoinserted radiolabel, was isolated. Additionally, these peptides had UV spectra that were markedly different from the nonphotolabeled peptides. The modified peptide from GDH corresponded to Cys270 through Lys289. Both sequencing and compositional analysis identified Glu275 as the site of photoinsertion. Sequencing of this peptide aborted at Glu275 after five rounds of analysis, indicating that insertion was blocking further progress. Compositional analysis showed that the entire sequence from residues 270 to 289 was present except that the single Glu residue was missing. This is interpreted as indicating that the photoinsertion is into the polypeptide backbone at the Glu site. The peptide isolated from LDH corresponded to Asp82 through Arg90. Sequencing of this peptide could be completed throughout with only the round at Tyr83 giving no identifiable residue. Compositional analysis of this peptide was in agreement with the peptide from Asp82 to Arg90 with the exception that the single Tyr residue was missing. This indicates that the photoinsertion is into the tyrosine side chain. This data was found to be in agreement with X-ray crystallographic results identifying the NAD(+)-binding domains.
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We demonstrate the accurate picoliter-scale dispensing of active proteins using a novel laser transfer technique. Droplets of protein solution are dispensed onto functionalized glass slides and into plastic microwells, activating as small as 50-microm diameter areas on these surfaces. Protein microarrays fabricated by laser transfer were assayed using standard fluorescent labeling techniques to demonstrate successful protein and antigen binding. These results indicate that laser transfer does not damage the active site of the dispensed protein and that this technique can be used to successfully fabricate a functioning protein microarray. Also, as a result of the efficient nature of the process, material usage is reduced by two to four orders of magnitude compared to conventional pin dispensing methods for protein spotting.
In our study, we estimated formaldehyde exposure levels of Korean medical students during their cadaver dissection practice hours. In addition, we examined the prevalence rates of formaldehyde-specific immunoglobulin E or immunoglobulin G antibodies and compared the results with the symptoms the students experienced as a result of formaldehyde exposure. There were 167 Korean medical students (i.e., subjects) aged 23.8+/-2.5 y (mean+/-standard deviation) and a control group of 67 premedical students aged 20.1+/-2.8 y (mean+/-standard deviation). Concentrations of formaldehyde in the cadaver dissection practice laboratory ranged from 0.194 to 11.245 mg/m3 (3.736+/-3.478 mg/m3 [mean+/-standard deviation]). Students reported by self-administered questionnaires that eye soreness (92.8%) and lacrimation (74.9%) were the most common symptoms they experienced during the laboratory sessions. One (0.6%) of the 167 medical students had a history of wheezing during dissection. Fourteen (8.4%) had specific immunoglobulin G antibody, but none had specific immunoglobulin E antibody. These results suggest that (a) Korean medical students are exposed to formaldehyde at a relatively high levels in their dissection practice hours, (b) specific immunoglobulin G is not related to adverse eye or respiratory symptoms, and (c) specific immunoglobulin E is rarely induced as a result of exposure to formaldehyde.
Treatment of Ca(2+) channel blockers (CCB) to relieve hypertension causes reversible male infertility, suggesting deregulation of Ca(2+) homeostasis in testis is closely related with male infertility. To investigate the possible toxicity of therapeutic application of CCB in childhood, the effect of nifedipine and ethosuximide, an L-type and T-type CCB, respectively, on the spermatogenesis and testicular gene expression was examined. Following the intraperitoneal injection of either drug for 7 days to 18 days on old mice, the paired testes weights were significantly lower in mice treated with nifedipine (> or = 10 mg/kg/day) or ethosuximide (100 mg/kg/day) than vehicle controls. In mice given high drug dosing (100 mg/kg), seminiferous tubules showed immaturity with spermatogenic arrest at elongating spermatid stage and poorly developed lumen. Unexpectedly, the expression of activator isoform of transcription factor cAMP-responsive element modulator (CREM) mRNA increased together with transition protein 2 and protamine 2 mRNA in drug-treated mice testes, suggesting that CCB may deregulate expression of activator isoform of CREM in male germ cells and that spermatogenic defect following CCB treatment may attribute to ectopic expression of CREM-dependent gene battery in testis. Therapeutic application of CCB in childhood should be cautious because of their potential to cause spermatogenic defect and altered gene expression in testis.