Osseointegration of anodized titanium implants under different current voltages: a rabbit study

The oxide layer that covers a titanium surface is extremely stable and appears to have excellent biocompatibility, which can result in successful osseointegration. The aim of this study was to analyse the characteristics of an oxide layer formed by anodic oxidation (anodization), and to evaluate the extent of bone healing around the anodized implant. The screw-type implants were made of commercially pure titanium (Grade 2). The Group 1 samples had a turned surface, and three other types of experimental specimens were anodized under constant voltages of 190 V (Group 2), 230 V (Group 3) and 270 V (Group 4). The surface characteristics of each sample type were inspected. Removal torque was measured after a 4-week healing period and the histomorphometric analysis was performed 6 weeks after implantation in rabbit tibiae. There was an increase in both the size and number of pores as the anodizing voltage increased. The Ra value of the Group 4 samples was higher than those in the Group 1 and 2 samples (P < 0.05). Group 3 showed a difference compared with Group 1 (P < 0.05). A thicker oxide layer, which contained crystalline (anatase) TiO(2) with the inclusion of some electrolytes (Ca, P), was formed at the higher anodizing voltage. Group 4 had higher removal torque values and percentages of bone-to-implant contact than the other groups (P < 0.05). The anodized titanium implants showed more intimate and stronger connections with peri-implant bone during early osseointegration than the turned titanium implants in this experimental model.

Attentional distractibility by optokinetic stimulation in Alzheimer disease

OBJECTIVE

Unilateral temporoparietal injury may result in an attentional deficit for stimuli presented in contralesional space. Thus, bilateral temporoparietal degeneration associated with Alzheimer disease (AD) might result in a bilateral attentional disturbance. Tests for hemispatial neglect, however, primarily assess spatial attentional asymmetries, and a bilateral attentional disorder might not be detected with these tests. The goal of this study was to learn whether optokinetic stimulation (OKS) would perturb the balanced attentional deficits of AD patients and alter their spatial allocation of attention.

METHODS

In Experiment I, 10 AD patients with bilateral temporoparietal glucose hypometabolism on PET and 10 controls bisected lines in two conditions: stationary solid lines superimposed on a moving background and "striped lines" where the whole line was stationary but the stripes within the line moved. The background OKS or the stripes within the line moved leftward or rightward or were stationary. In Experiment II, to investigate whether the influence of background movements would increase with AD severity, we conducted a similar experiment in 56 patients with various stages of AD.

RESULTS

In Experiment I, the line bisection errors (LBEs) of AD subjects, but not of the controls, were markedly influenced by both background and within line stripe motions, deviations occurring in the same direction of movement. In Experiment II, LBEs also occurred in the same direction as background movement and increased with dementia severity.

CONCLUSIONS

These results demonstrate that patients with Alzheimer disease are spatially distracted by moving stimuli.

Three dimensional reconstruction of conventional stereo optic disc image

Stereo disc photograph was analyzed and reconstructed as 3 dimensional contour image to evaluate the status of the optic nerve head for the early detection of glaucoma and the evaluation of the efficacy of treatment. Stepwise preprocessing was introduced to detect the edge of the optic nerve head and retinal vessels and reduce noises. Paired images were registered by power cepstrum method and zero-mean normalized cross-correlation. After Gaussian blurring, median filter application and disparity pair searching, depth information in the 3 dimensionally reconstructed image was calculated by the simple triangulation formula. Calculated depth maps were smoothed through cubic B-spline interpolation and retinal vessels were visualized more clearly by adding reference image. Resulted 3 dimensional contour image showed optic cups, retinal vessels and the notching of the neural rim of the optic disc clearly and intuitively, helping physicians in understanding and interpreting the stereo disc photograph.

Treatment of non-biodegradable cutting oil wastewater by ultrasonication-Fenton oxidation process

To treat cutting oil wastewater produced in metal surface treatment industry, Ultrasonication (US)-Fenton process, which is one of the advanced oxidation processes, was used. The optimum conditions to treat non-biodegradable pollutants using the US-Fenton process were that the application rates of H2O2 and FeSO4 were 10% and 3 g/L, respectively, the value of pH was 3, and the ultrasonication time was 30 min. It identified non-degradable pollutants such as ethylene diamine tetraacetic acid (EDTA) and Triethanolamine (TEA) in the cutting oil wastewater. TLC analysis of two compounds of treated water by the coagulation process was similar to that of raw water. However, TLC analysis of two compounds of US-Fenton process was different from that of raw water, meaning that US-Fenton process decomposed the EDTA and TEA. To study the possibility of application with the US-Fenton process to pilot plant, the pollutants treatment efficiency of three different methods, such as US-Fenton process, activated sludge process and coagulation process, in continuous experiments were compared. The removal rate of pollutants by the US-Fenton process according to the effluent time was higher than any other processes. The removal rates of COD, SS, T-N and T-P by US-Fenton process were 98, 93, 75 and 95%, respectively.

Development and evaluation of triplex PCR for direct detection of mycobacteria in respiratory specimens

AIMS

To develop a method for the simultaneous detection of Mycobacterium tuberculosis, Mycobacterium avium-intracellularecomplex (MAC), and other mycobacteria in clinical specimens using triplex PCR.

METHODS AND RESULTS

The target of amplification was the internal transcribed spacer region between the l6S and 23S rDNA genes. Twenty-two mycobacterial type strains, 118 M. tuberculosis, 87 other mycobacteria, 75 nonmycobacterial pathogens, 115 respiratory specimens from confirmed cases of tuberculous or other mycobacterial diseases, and sputa from 50 patients with nonmycobacterial respiratory diseases were tested. In M. tuberculosis, 322 bp pan-mycobacterial and 133 bp species-specific bands were observed. In MAC, the respective bands were 322 and 84 bp. The other mycobacteria showed single pan-mycobacterial bands of approx. 300-350 bp. Nonspecific amplicons were not found in any of the nonmycobacterial pathogens. In the tuberculosis specimens, 96.4% of smear-positive specimens and 70.2% of smear-negative specimens showed positive reactions. Specimens from two patients with MAC infection were MAC positive. Only 1 of 50 specimens from nonmycobacterial diseases was positive (2.0%).

CONCLUSION, SIGNIFICANCE AND IMPACT OF THE STUDY

Triplex PCR enables accurate and rapid diagnosis of tuberculosis and probably is useful for the detection of MAC and other mycobacteria in respiratory specimens.

Increased telomerase activity and human telomerase reverse transcriptase mRNA expression in the endometrium of patients with endometriosis

BACKGROUND

Endometriosis is considered a frequent, benign disease with the ability to undergo neoplastic processes. The aim of this study was to evaluate the limitless replication potential of the endometrium in patients with endometriosis by examining human telomerase reverse transcriptase (hTERT) mRNA expression and telomerase activity.

METHODS

Endometrium samples from 30 endometriosis patients and 30 patients without endometriosis were obtained via endometrial biopsy. The expression of hTERT mRNA was determined by real-time RT-PCR assay, and telomerase activity was measured by telomerase repeat amplification protocol (TRAP) assay.

RESULTS

The mean normalized hTERT (N hTERT) mRNA level was significantly higher in the endometriosis than in the control group (P = 0.013). The mean hTERT mRNA levels during the proliferative phase and during the secretory phase were higher in the endometriosis group than in the control group, although the difference was only significant for the secretory phase (P = 0.036). We found a prominent difference in endometrial telomerase activity between moderate-to-severe endometriosis and the control group (P = 0.048). The levels of hTERT mRNA and telomerase activity increased as the disease became more severe (P = 0.038, P = 0.016).

CONCLUSIONS

This study showed the overexpression of hTERT mRNA and telomerase activity in the endometrium of endometriosis patients. These finding suggest that replication potential of endometrial cells may have an important role in the pathogenesis of endometriosis.

Use of hydrocyclone and flotation column for reducing the volume of contaminated dredged material

As sediment contamination problems have recently been raised in Korea, the need for technologies to clean contaminants in sediments has increased. Although the recalcitrant organic matters and heavy metals in the contaminated sediments are of primary concern, large amounts of sediment makes the removal of the contaminants in them more difficult. In this study, the performance of hydrocyclone and flotation column was tested to reduce the volume of contaminated dredged materials (CDMs) prior to treating recalcitrant matters, such as various organic chemicals and heavy metals, in an integrated treatment system. When hydrocyclone was operated with 10% (w/v) solids concentration of the feed slurry, the total solids of upflow products were 4 to 7% (w/v) when the inlet pressure was changed from 1.0 to 2.0 kg/cm2. The volume reduction ratio of CDMs by hydrocyclone was approximately 90% (v/v). When the upflow products in hydrocyclone was then spiked with automobile transmission oil and fed to the flotation colum to see the performance of the column flotation on the volume reduction and the TPH removal, 44% of the TPHs in feed were removed at the tails and the volume reduction ratio of CDMs by column flotation was 18% at 200 L/min of wash water. The flotation column could be proposed as a potential preliminary treatment process of CDMs prior to subsequent biological treatments.

Docetaxel (Taxotere), cisplatin, UFT, and leucovorin combination chemotherapy in advanced gastric cancer

We conducted this study to ascertain the efficacy and toxicity of docetaxel and cisplatin combined with oral UFT and leucovorin as a first-line treatment for patients with advanced gastric cancer. In all, 52 patients received courses of docetaxel 60 mg m(-2) intravenously (i.v.) for 1 h and then cisplatin 75 mg m(-2) i.v. for 2 h on day 1. Oral UFT at 400-600 mg day(-1), as determined by body surface area, and leucovorin at 75 mg day(-1) were administered for 21 consecutive days from day 1, and this was followed by a 7-day drug-free interval. A total of 225 courses were administered, and the median number of courses per patient was four. Four complete responses (7.7%) and 22 partial responses (42.3%) were achieved, giving an overall response rate of 50% (95% Confidence Interval: 36.4-63.6%). The major toxicity was neutropenia, which reached grade 3/4 in 36 patients (69.3%). Grade 3/4 nausea and vomiting was observed in 12 patients (23.1%). Median time to progression was 22 weeks (4 to 156+ weeks), median survival duration was 48 weeks (4 to 156+ weeks), and median response duration was 24 weeks (6-152 weeks). We conclude that docetaxel, cisplatin, oral UFT, and leucovorin combination chemotherapy is effective and tolerable for the treatment of advanced gastric cancer.

Efficacy of amblyopia therapy initiated after 9 years of age

AIMS/PURPOSE

To evaluate the efficacy of occlusion therapy initiated after 9 years of age.

METHODS

A total of 16 amblyopes of 9 years or older (range, 9.0-14.5 years; mean, 10.5 years) with a difference in visual acuity of over two lines between the eyes alter 4 weeks of first full-time spectacle wear were included. None of the children had undergone a previous ocular examination, had ever worn spectacles, received occlusion therapy, or had strabismus surgery. Initial worst visual acuity after 4 weeks of full-time spectacle wear was 20/100 in three patients, between 20/80 and 20/40 in 11 patients, and 20/30 in two patients. Full-time occlusion was performed in 14 patients and part-time occlusion in two patients.

RESULTS

The final visual acuity of 15 out of 16 patients (94%) improved at least two lines. The final visual acuities ranged from 20/30 to 20/20 in 14 patients, 20/40 in one patient, and 20/50 in one remaining patient who began amblyopia therapy at 14.5 years of age, with the poorest compliance among the patients.

CONCLUSIONS

Occlusion therapy for anisometropic and strabismic amblyopia can be successful even if initiated after the age of 9 years.

Granulocytic sarcoma of the uterine cervix

Granulocytic sarcoma (GS) is a rare manifestation of leukemia and has been reported in 3-5% of acute myelogenous leukemia (AML) patients. GS in the uterine cervix is very rare and is also called chloroma because of its greenish appearance. We present the case of a patient whose disease relapsed as chloroma of the uterine cervix after bone marrow transplantation (BMT). She remained in continuous complete remission for 2 years after allogeneic BMT. However, she visited the hospital because of painless vaginal bleeding. She was diagnosed as having chloroma by cervical smear and colposcopically directed biopsy of the cervix. Systemic chemotherapy was administered on the presumption that myelogenous leukemia had recurred as chloroma, and a good clinical response was achieved. We describe the first case of AML that relapsed as chloroma of the uterine cervix after complete remission of the AML, which had complete response to only systemic chemotherapy.

Misidentification of Aeromonas veronii biovar sobria as Vibrio alginolyticus by the Vitek system

AIMS

To find the cause of misidentification of aeromonads when using the Vitek system.

METHODS AND RESULTS

Two Aeromonas veronii biovar sobria isolates were misidentified as Vibrio alginolyticus by the Vitek system. Both strains' identification was confirmed by biochemical testing, API 20E/20NE kits and/or 16S RFLP analysis. Thirty-one known Aeromonas species were tested by the Vitek system using 0.45 and 0.85% saline in the suspension medium. It was not clear whether low salinity causes misidentification of Aeromonas species more frequently.

CONCLUSIONS

The specified reaction time may be inappropriately short for some critical biochemical tests of some strains. An ingenious reading strategy regarding incubation time is necessary to improve identification of Aeromonas species by the Vitek system.

SIGNIFICANCE AND IMPACT OF THE STUDY

To our knowledge, this is the first report of misidentification of A. veronii biovar sobria as V. alginolyticus in the Vitek system.

Relationship between urinary profile of the endogenous steroids and postmenopausal women with stress urinary incontinence

AIMS

The aims of this study were to investigate whether endogenous steroid hormones are (1) related to pathogenesis of stress urinary incontinence after menopause, (2) are related to severity of stress urinary incontinence, and (3) are related to prognostic parameters of stress urinary incontinence.

METHODS

Twenty post-partum women with clinically diagnosed stress urinary incontinence and 20 age-matched postmenopausal women without stress urinary incontinence (control group) were evaluated. We compared urinary profile of the endogenous steroid hormones patients with stress urinary incontinence and controls, and between grade I and grade II of stress urinary incontinence. We also investigated the relationship between urinary profile of the endogenous steroid hormones and prognostic parameters of stress urinary incontinence (maximal urethral closure pressure, functional urethral length, Valsalva leak point pressure, cough leak point pressure, posterior urethrovesical angle, bladder neck descent, and stress urethral axis). The ages of the patients and those in the control group were 64.3 +/- 5.6 and 57.5 +/- 3.8 years old and the body mass indexes were 24.96 +/- 3.14 and 22.11 +/- 2.73 kg/m2 in patients and in normal subjects, respectively. Nine patients were grade I and 11 were grade II. Estrone and 17beta-estradiol only were detected in all subjects, regardless of control or patient group. It is noteworthy that there were no significant differences (P > 0.05) in the levels of estrone and 17beta-estradiol in the urine of postmenopausal normal subjects compared with in the urine of postmenopausal patients with urinary incontinence. E2/E1 ratio was not different between the two groups (P > 0.05). Among the objective steroids, DHEA, Delta4-dione, Delta5-diol, Te, DHT, 16alpha-DHT, 11-keto An, THDOC, and THB were not detected either in the urine of normal subjects and nor in the urine of the patients. After comparing androgen levels between normal subjects and patients, no significant differences (P>0.05) were detected, except for 5alpha-THB and 5alpha-THF. Neither 5alpha-THB or 5alpha-THF were detected in the patients' urine. Et/An (11beta-OH Et/11beta-OH An) concentration ratios were not significantly different between the two groups, either (P > 0.05). There were not significant differences of concentrations (micromol/g creatinine) of urinary steroids between grade I and grade II of stress urinary incontinence. Pregnanediol was significantly related to bladder neck descent in supine and sitting positions (R = 0.79, P = 0.01, and R = 0.73, P = 0.03, respectively), and pregnanetriol was significantly related to maximal urethral closure pressure and functional urethral length (R = 0.68, P = 0.04, and R = -0.79, P = 0.01, respectively). Androsterone was significantly related to bladder neck descent in supine and sitting positions (R = 0.68, P = 0.04, and R = 0.78, P = 0.01, respectively). 5-AT was significantly related to bladder neck descent in sitting position and stress urethral axis (R = 0.72, P = 0.03, and R = -0.71, P = 0.03). 11-keto Et was significantly related to bladder neck descent in supine and sitting positions and related to stress urethral axis (R = 0.82, P = 0.01, and R = 0.81, P = 0.01, R = -0.67, P = 0.04, respectively). THS was significantly related to bladder neck descent in supine and sitting positions and related to stress urethral axis (R = 0.76, P = 0.02, and R = 0.74, P = 0.02, R = -0.68, P = 0.04, respectively). THE was significantly related to bladder neck descent in sitting position (R = 0.67, P = 0.04).beta-Tetrahydrocortisol/alpha-tetrahydrocortisol (beta-THF/alpha-THF) and alpha-cortol were significantly related to maximal urethral closure pressure and functional urethral length (R = 0.74, P = 0.02, and R = -0.92, P = 0.01; R = 0.71, P = 0.36, and R = -0.87, P = 0.000, respectively). 17beta-estradiol (E2) was significantly related to bladder neck descent in supine position (R = -0.62, P = 0.04) and 17beta-estradiol/estrone (E2/E1) was significantly related to cough leak point pressure (R = 0.79, P = 0.01). In conclusion, the urinary concentrations of endogenous steroid metabolites in postmenopausal patients with stress urinary incontinence were not significantly different from normal patients and were not significantly different between grade I and grade II patients with stress urinary incontinence. Some endogenous steroid metabolites were positively or negatively significantly related to prognostic parameters of stress urinary incontinence.

Comparison of localised nerve fibre layer defects in normal tension glaucoma and primary open angle glaucoma

AIM

To compare the pattern of localised nerve fibre layer (NFL) defects in normal tension glaucoma (NTG) and primary open angle glaucoma (POAG).

METHODS

50 NTG eyes and 36 POAG eyes, all with localised NFL defects, were enrolled. On retinal NFL photography, the proximity of the defect to the centre of the fovea (angle alpha) and the sum of the angular width of the defects (angle beta) were determined. Angle alpha was the angle made by a line from the centre of the fovea to the disc centre and a line from the disc centre to the disc margin, where the nearest border of the defect met. The patterns of localised NFL defects in NTG and POAG were compared with angles alpha and beta. Independent t test was used for statistical analysis.

RESULTS

Angle alpha in NTG (35.1 (SD 20.0) degrees ) was significantly smaller than that of POAG (45.9 (21.9) degrees ) (p=0.02), while angle beta in NTG (49.0 (31.9) degrees ) was significantly larger than that of POAG (33.1 (23.9) degrees ) (p=0.01).

CONCLUSIONS

The pattern of NFL defects in NTG was different from that in POAG. Localised NFL defects in NTG were closer to the fovea and wider in width than those in POAG.

Zinc translocation accelerates infarction after mild transient focal ischemia

Excess release of chelatable zinc (Zn(2+)) from central synaptic vesicles may contribute to the pathogenesis of selective neuronal cell death following transient forebrain ischemia, but a role in neurodegeneration after focal ischemia has not been defined. Adult male Long-Evans rats subjected to middle cerebral artery occlusion (MCAO) for 30 min followed by reperfusion developed delayed cerebral infarction reaching completion 3 days after the insult. One day after the insult, many degenerating cerebral neurons exhibited increased intracellular Zn(2+), and some labeled with the antibody against activated caspase-3. I.c.v. administration of the Zn(2+) chelator, EDTA saturated with equimolar Ca(2+) (CaEDTA), 15 min prior to ischemia attenuated subsequent Zn(2+) translocation into cortical neurons, and reduced infarct volume measured 3 days after ischemia. Although the protective effect of CaEDTA at this endpoint was substantial (about 70% infarct reduction), it was lost when insult severity was increased (from 30 to 60 min MCAO), or when infarct volume was measured at a much later time point (14 days instead of 3 days after ischemia). These data suggest that toxic Zn(2+) translocation, from presynaptic terminals to post-synaptic cell bodies, may accelerate the development of cerebral infarction following mild transient focal ischemia.

The effectiveness of modified six-corner suspension in patients with paravaginal defect and stress urinary incontinence

The purpose of our study was to evaluate the effectiveness of a modified six-corner suspension in patients with a paravaginal defect and stress urinary incontinence (SUI) by observing changes in the POP (pelvic organ prolapse) stage, substage, and the cure rates in SUI. Forty-two women patients who had a paravaginal defect and stress urinary incontinence were treated by a modified six-corner suspension at the urogynecology clinic, Yonsei University Medical Center between January 1999 and March 2000. Each patient underwent a complete physical examination and a standardized urogynecologic interview that asked about age, hormone replacement, parity, urinary symptoms and previous gynecologic surgery. From the 42 patients who had the operation, 30 patients with 1-year follow-up made up the study group. Changes from stage III ( n = 18, 60%) of the group to stage I ( n = 6, 33.3%) or stage 0 ( n = 12, 66.6%) were observed 3 months after surgery, and no further changes were observed up to 1 year after surgery, except in one case. Changes from stage IV ( n = 12) to stage 0 ( n = 3, 25%) or stage I ( n = 6, 50%) or stage II ( n = 6, 50%) were observed 3 months after surgery, but no further change was observed up to 1 year later. Changes from substage Aa (+2, +3) to -3 ( n = 27, 90%) and from substage Ba (+2,+3,+4,+5,+6,+7) to -3 ( n = 27, 90%) were observed 3 months after surgery. No further changes were observed up to 1 year. The average length of the genital hiatus was initially 4.95 cm and 2.5 cm 3 months after surgery. Little change (2.6 cm) was observed up to 1 year later. When the patients were assessed clinically by urodynamics and physical examination, none had urinary leakage symptoms up to 1 year after the operation. All patients had excellent functional results and no postoperative complaints of stress urinary incontinence. We observed that a modified six-corner suspension was surprisingly effective in patients having a paravaginal defect and a stress urinary incontinence.

Relationship between stress urinary incontinence and pelvic organ prolapse

We investigated the objective coexisting rate of stress urinary incontinence and pelvic organ prolapse, and also compared the treatment outcomes in patients who had both conditions, treated by a corrective operation on the basis of a precise preoperative evaluation. We reviewed 97 cases who underwent urodynamic studies and evaluation of the prolapse according to the Pelvic Organ Prolapse Quantification (POP-Q) system from among patients who were admitted for treatment of either stress urinary incontinence or pelvic organ prolapse. A Burch urethropexy, either alone or with a parvaginal repair, was done to correct the stress urinary incontinence, as well as additional operations to correct prolapse of stage II or more. The patients were evaluated postoperatively for the stress urinary incontinence and the degree of prolapse at every visit. Nineteen of 30 (63.3%) patients who were admitted with stress urinary incontinence had a coexisting pelvic organ prolapse, most often of the anterior wall. In 42 of 67 (62.7%) cases admitted with pelvic organ prolapse there was a coexisting stress urinary incontinence. A total of 61 patients who had both conditions were followed for 12 months postoperatively. The recurrence rate of stress urinary incontinence and prolapse (all of which were stage II) was 3.3% and 18.0%, respectively. It was noted that the greater the preoperative stage, the higher the recurrence rate (stage II 4.35%; stage III 25.0%; stage IV 33.6%). The coexisting rates of pelvic organ prolapse in patients having stress urinary incontinence, and stress urinary incontinence in patients having a pelvic organ prolapse, were both high. Therefore, when a preoperative evaluation that simultaneously considers both conditions and the correcting surgery is based on this evaluation, the recurrence rates of both conditions could be lowered.

Solution conformation of alpha-conotoxin EI, a neuromuscular toxin specific for the alpha 1/delta subunit interface of torpedo nicotinic acetylcholine receptor

A high resolution structure of alpha-conotoxin EI has been determined by (1)H NMR spectroscopy and molecular modeling. alpha-Conotoxin EI has the same disulfide framework as alpha 4/7 conotoxins targeting neuronal nicotinic acetylcholine receptors but antagonizes the neuromuscular receptor as do the alpha 3/5 and alpha A conotoxins. The unique binding preference of alpha-conotoxin EI to the alpha(1)/delta subunit interface of Torpedo neuromuscular receptor makes it a valuable structural template for superposition of various alpha-conotoxins possessing distinct receptor subtype specificities. Structural comparison of alpha-conotoxin EI with the gamma-subunit favoring alpha-conotoxin GI suggests that the Torpedo delta-subunit preference of the former originates from its second loop. Superposition of three-dimensional structures of seven alpha-conotoxins reveals that the estimated size of the toxin-binding pocket in nicotinic acetylcholine receptor is approximately 20 A (height) x 20 A (width) x 15 A (thickness).

Catalytic asymmetric synthesis of cyclopentenones from propargyl malonates and allylic acetate by successive action of homogeneous palladium(II) and cobalt on charcoal catalysts in a one-pot reaction

The tandem action of a homogeneous chiral Pd(II) catalyst and a heterogeneous Co/C catalyst leads to a two-step one-pot highly enantioselective Pauson-Khand-type reaction.

Analysis of vivax malaria cases in Gangwon-do (province), Korea in the year 2000

A total of 827 malaria cases were reported in the Gangwon-do in the year 2000. There were 18.2 cases per 100,000 inhabitants. There were 283 cases among civilians and 544 cases among the military. 90.6% of cases were reported in Cheorwon--(531), Hwacheon--(152), and Goseong--(66) gun (county), which bordered the demilitarized zone (DMZ). A distinct feature pertaining to the malaria cases in Gangwon-do is that the number of cases has increased about two times over the last year. The mean time from the beginning of symptoms to malaria diagnosis was five days. Control systems for malaria by public health organizations and military organizations are well maintained, but were not able to reduce the malaria prevalence rate. The cause for the increase in pattern of the malaria cases in Gangwon-do may be caused by the spreading of prevalent areas of malaria to the east. Continuous endeavor such as early detection of cases, early treatment, education on clinical symptoms and prevention of mosquito bites with repellent and mosquito nets will help to reduce the infection rate of malaria in Gangwon-do.

Modulation of the multisubstrate specificity of Thermus maltogenic amylase by truncation of the N-terminal domain and by a salt-induced shift of the monomer/dimer equilibrium

The relation between the quaternary structure and the substrate specificity of Thermus maltogenic amylase (ThMA) has been investigated. Sedimentation diffusion equilibrium ultracentrifugation and gel filtration analyses, in combination with the crystal structure determined recently, have demonstrated that ThMA existed in a monomer/dimer equilibrium. The truncation of ThMA by removing the N-terminal domain, which is composed of 124 amino acid residues, resulted in the complete monomerization of the enzyme (ThMADelta124) accompanied by a drastic decrease in the activity for beta-cyclodextrin (beta-CD) and a relatively smaller reduction of the activity for starch. Despite the overall low activity of ThMADelta124, the activity was higher toward starch than beta-CD, and the ratio of the specific activities toward these substrates was approximately 100 fold higher than that of wild-type ThMA. Furthermore, the addition of KCl to wild-type ThMA shifted the monomer/dimer equilibrium toward the monomer. In the presence of 1.0 M KCl, the relative activity of ThMA toward beta-CD decreased to 74%, while that for soluble starch increased to 194% compared to the activities in the absence of KCl. Thus, the ThMA monomer and dimer are both inferred to be enzymatically active but with a somewhat different substrate preference. Kinetic parameters of the wild-type and truncated enzymes also are in accordance with the changes in their specific activities. We thus provide evidence in support of a model, which shows that the relative multisubstrate specificity of ThMA is influenced by the monomer/dimer equilibrium of the enzyme.

Anti-inflammatory effect of adenovirus-mediated IkappaBalpha overexpression in respiratory epithelial cells

Many studies into basic biological characteristics of inflammation and tissue injury have implicated pro-inflammatory cytokine-mediated tissue injury in the pathogenesis of inflammatory lung diseases. Because transcription of most proinflammatory cytokines is dependent on the activation of nuclear factor (NF)-kappaB, NF-kappaB could be a good potential target to suppress the cytokine cascade. Cytokine-induced activation of NF-kappaB requires phosphorylation and subsequent degradation of IkappaBa. Therefore, the blocking NF-kappaB activation by IkappaBalpha could inhibit the pro-inflammatory cytokine-induced tissue injury. To evaluate whether blocking of NF-kappaB activation shows an anti-inflammatory effect, this study investigated the effect of adenovirus-mediated overexpression of IkappaBalpha super-repressor (IkappaBalpha-SR) on the pro-inflammatory cytokine expression in respiratory epithelial cells. The transduction efficiency of adenovirus was >90% in both A549 and NCI-H157 cells. Ad5IkappaBalpha-SR-transduced cells expressed high levels of IkappaBalpha-SR, which was resistant to tumour necrosis factor (TNF)-alpha-induced degradation. Adenovirus-mediated overexpression of IkappaBalpha-SR blocked cytokine-induced nuclear translocation of p65 and NF-kappaB deoxyribonucleic acid binding activity without affecting total cellular expression level of NF-kappaB. Ad5IkappaBalpha-SR transduction suppressed cytokine-induced interleukin-8 and TNF-alpha expressions at both ribonucleic acid and protein levels. These results suggest that blocking the nuclear factor-kappaB pathway by adenovirus-mediated overexpression of IkappaBalpha-super-repressor shows an effective anti-inflammatory effect in respiratory epithelial cells.

Downregulation of Bcl-2 and activation of caspase-8 in the UVB-induced apoptosis of a cultured human melanoma cell line

PURPOSE

This study was performed to determine the effect of UV radiation on the activation of apoptosis regulatory proteins using cultured human melanoma cells.

METHODS

G361 lightly pigmented melanoma cells were irradiated with increasing doses of UVB and analyzed for an apoptotic mechanism using a cell viability test, TEM, FACS, and western blotting analysis.

RESULTS

TEM and FACS showed apoptotic features of cell death after UVB irradiation. Western blotting disclosed downregulation of Bcl-2 and the activation of caspase-9. Caspase-8, a downstream molecule of Fas/FasL interaction, was also activated. The activation of downstream molecules of both caspase-8 and caspase-9 was also demonstrated.

CONCLUSION

Our data showed that the regulation of the Bcl-2 family and caspase-8 may work together to activate a caspase-3 mediated apoptotic pathway following UVB irradiation of cultured human melanoma cells.

The tumor cells in nodular lymphocyte-predominant Hodgkin disease are clonally related to the large cell lymphoma occurring in the same individual. Direct demonstration by single cell analysis

Large cell lymphoma (LCL) sometimes occurs concurrently or subsequently in patients with nodular lymphocyte-predominant Hodgkin disease (NLPHD). Although there is evidence of a clonal relationship between LCL and NLPHD, there has been no direct demonstration that the lymphocytic and histiocytic (L&H) cells in NLPHD are related to the tumor cells in LCL. We identified 2 cases of NLPHD with an associated LCL. Single L&H cells, the Reed-Sternberg cell variants in NLPHD, were isolated from immunostained tissue sections by micromanipulation, and the immunoglobulin heavy chain gene (IgH) complementarity determining region (CDR) III of the cells was amplified by the polymerase chain reaction (PCR). The products were compared with those obtained from microdissected LCL cells using polyacrylamide gel electrophoresis and nucleotide sequencing. The IgH CDRIII sequences from the L&H cells were related to each other, but also showed nucleotide substitutions, consistent with a germinal center origin. The sequences from the L&H cells also were related to those from the corresponding LCL cells. We have provided direct evidence through sequence analysis of the IgH CDRIII that the L&H cells are clonally related to the corresponding LCL arising in 2 cases of NLPHD.