Assisted reproductive techniques and subsequent risk of asthma and allergic rhinitis in offspring: a nationwide birth cohort study in South Korea

OBJECTIVE

The relationship between assisted reproductive techniques (ART) and the risk of asthma and allergic rhinitis (AR) is controversial. Thus, we aimed to investigate the relationship between ART and the risk of asthma and AR in a nationwide, large-scale birth cohort.

PATIENTS AND METHODS

This study utilized the National Health Insurance Service data in South Korea to conduct a nationwide, large-scale, population-based birth cohort. We included all infants born between 2017 and 2018. AR, asthma, food allergies, and atopic dermatitis were defined using the International Classification of Diseases tenth edition codes. Asthma was classified as allergic or non-allergic based on accompanying allergic diseases (AR, food allergy, or atopic dermatitis). Using 1:10 propensity score matching, we compared infants conceived through ART with those conceived naturally (non-ART). After matching, logistic regression was used to compare the hazard ratio for asthma and AR between the two groups.

RESULTS

We included 543,178 infants [male infants, 280,194 (51.38%)]. After matching, 8,925 and 74,229 infants were selected for the ART and non-ART groups, respectively. The ART group showed a decreased risk of asthma in the offspring [adjusted hazard ratio (aHR), 0.45; 95% confidence interval (CI), 0.41-0.48]. Similarly, for AR, being conceived by ART was associated with a decreased risk of AR (aHR, 0.25; 95% CI, 0.12-0.37). ART offspring showed a decreased risk of asthma and AR in offspring compared to that observed in non-ART offspring.

CONCLUSIONS

Our study offers important insights for clinicians, researchers, and parents regarding the health outcomes of ART-conceived infants and enhances our understanding of ART's impact on respiratory health.

Transition Metal Ion Doping on ZIF-8 Enhances the Electrochemical CO2 Reduction Reaction

The electrochemical reduction of CO2  to diverse value-added chemicals is a unique, environmentally friendly approach for curbing greenhouse gas emissions while addressing sluggish catalytic activity and low Faradaic efficiency (FE) of electrocatalysts. Here, zeolite-imidazolate-frameworks-8 (ZIF-8) containing various transition metal ions-Ni, Fe, and Cu-at varying concentrations upon doping are fabricated for the electrocatalytic CO2 reduction reaction (CO2 RR) to carbon monoxide (CO) without further processing. Atom coordination environments and theoretical electrocatalytic performance are scrutinized via X-ray absorption spectroscopy (XAS) and density functional theory (DFT) calculations. Upon optimized Cu doping on ZIF-8, Cu0.5 Zn0.5 /ZIF-8 achieves a high partial current density of 11.57 mA cm-2 and maximum FE for CO of 88.5% at -1.0 V (versus RHE) with a stable catalytic activity over 6 h. Furthermore, the electron-rich sp2 C atom facilitates COOH* promotion after Cu doping of ZIF-8, leading to a local effect between the zinc-nitrogen (Zn-N4 ) and copper-nitrogen (Cu-N4 ) moieties. Additionally, the advanced CO2 RR pathway is illustrated from various perspectives, including the pre-H-covered state under the CO2 RR. The findings expand the pool of efficient metal-organic framework (MOF)-based CO2 RR catalysts, deeming them viable alternatives to conventional catalysts.

Production of H2-Free Carbon Monoxide from Formic Acid Dehydration: The Catalytic Role of Acid Sites in Sulfated Zirconia

The formic acid (CH₂O₂) decomposition over sulfated zirconia (SZ) catalysts prepared under different synthesis conditions, such as calcination temperature (500-650 °C) and sulfate loading (0-20 wt.%), was investigated. Three sulfate species (tridentate, bridging bidentate, and pyrosulfate) on the SZ catalysts were characterized by using temperature-programmed decomposition (TPDE), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The acidic properties of the SZ catalysts were investigated by the temperature-programmed desorption of iso-propanol (IPA-TPD) and pyridine-adsorbed infrared (Py-IR) spectroscopy and correlated with their catalytic properties in formic acid decomposition. The relative contributions of Brønsted and Lewis acid sites to the formic acid dehydration were compared, and optimal synthetic conditions, such as calcination temperature and sulfate loading, were proposed.

Analysis of predisposing factors in unilateral maxillary sinus fungal ball: the predictive role of odontogenic and anatomical factors

BACKGROUND

The pathogenesis of maxillary sinus fungal ball (MSFB) is explained by aerogenic and odontogenic factors. We evaluated the predisposing factors, including intranasal anatomical and dental factors for increased diagnostic accuracy.

METHODOLOGY

In this study, 117 patients who underwent endoscopic sinus surgery for unilateral MSFB were included. Preoperative computed tomography (CT) scans were used to analyze the presence of anatomical variations (anterior and posterior nasal septal deviation (NSD), concha bullosa (CB), infraorbital cell (haller cell), paradoxical middle turbinate, everted uncinate process and MS size). Dental factors including history of dental procedures and findings on CT scans were reviewed.

RESULTS

Anterior and posterior NSD toward non-affected side were significantly associated with the presence of FB. The presence of CB and infraorbital cell was higher in the non-affected side rather than in the lesion side. Compared to non-affected MS, FB-presence MS was shallower and had a larger height to depth ratio. The presence of dental history was significantly higher on FB-presence MS than non-affected MS. In multivariable analysis, posterior NSD toward non-affected side, dental history increased the aOR of MSFB, while the presence of CB and infraorbital cell decreased the aOR of MSFB.

CONCLUSIONS

The occurrence of MSFB seems to be associated with ipsilateral odontogenic factors, followed by anatomic variations including posterior NSD toward non-affected side and absence of CB and infraorbital cell.

Selective hydrogenation of CO2 to CH4 over two-dimensional nickel silicate molecular sieves

Two-dimensional (2D) Ni-containing delaminated MWW layers (Ni-DML) were synthesized by hydrothermal treatment of a borosilicate MWW precursor with a nickel nitrate solution, and their catalytic properties were investigated for the...

Defect-stabilized nickel on beta zeolite as a promising catalyst for dry reforming of methane

Four different Ni-containing beta zeolite (Ni-BEA) catalysts were synthesized and applied for dry reforming of methane (DRM). Ni-BEA(I) exhibiting a nickel silicate was synthesized via the single-step interzeolite transformation of...

Rational Design of Pomegranate-like Base-Acid Bifunctional β Zeolite by Steam-Assisted Crystallization for the Tandem Deacetalization-Knoevenagel Condensation

A highly crystalline pomegranate-like base-acid bifunctional beta zeolite was successfully synthesized by the steam-assisted crystallization method using a basic nitrided N-beta as the starting material. The secondary crystal growth of a beta zeolite generating acid functionality occurred over the outer surface and intercrystalline void spaces of the N-beta zeolite. The pomegranate-like N-beta@H-beta zeolite had a high surface area and base-acid dual functionality because of the well-connected framework topologies of the H-beta and N-beta crystallites. The N-beta@H-beta zeolite exhibited a superior yield of benzylidenemalononitrile during the tandem deacetalization-Knoevenagel condensation of benzaldehyde dimethyl acetal and malononitrile compared to H-beta, N-beta, and their physical mixture. This is likely due to the isolated and balanced activity of the base- and acid-catalyzed reactions.

Trabecular bone score value is associated with new bone formation independently of fat metaplasia on spinal magnetic resonance imaging in patients with ankylosing spondylitis

OBJECTIVE

To evaluate the association between trabecular bone score (TBS) and new bone formation in ankylosing spondylitis (AS) patients, and to investigate whether TBS is independently associated with new bone formation.

METHOD

Sixty-eight patients with AS underwent spinal magnetic resonance imaging (MRI) and dual-energy X-ray absorptiometry of the lumbar spine to measure TBS and bone mineral density at baseline. Lateral radiographs of the cervical and lumbar spine (baseline and 2 years) were assessed for new bone formation (syndesmophyte formation and/or growth combined), and spinal MRIs were assessed for the presence or absence of fat metaplasia (FM) at the first to fourth lumbar vertebrae. The factors associated with new bone formation were analysed at the patient level and the vertebral level.

RESULTS

New bone formation had developed in 17 patients (25%) at 2 year follow-up. Patients with new bone formation had a higher prevalence of FM and lower TBS at baseline than patients without new bone formation (p = 0.013 and p = 0.041). At the patient level, FM on MRI and low TBS (< 1.23) were significantly associated with new bone formation. At the vertebral level, new bone formation had developed in 25 out of 231 vertebrae (11%) after 2 years. Vertebrae with both FM on MRI and low TBS tended to have more new bone formation (p < 0.001). Syndesmophytes and low TBS (< 1.23) independently increased the risk of new bone formation at the level of individual vertebrae.

CONCLUSION

At both patient and individual vertebral levels, low TBS was associated with new bone formation independently of FM on MRI.

Lumbar Disc Herniation Within Solid Fused Segments After Removal of Pedicle Screws: A Case Report

CASE

A 73-year-old man with instrumented fusion of L3-4-5 underwent the removal of previous pedicle screws and posterior instrumented fusion of L1-2-3. The solid dorsal fusion mass of L3-5 was identified intraoperatively and preoperatively. At 3 years after the second surgery, he presented with abrupt radiating pain in the left leg. Plain radiographs showed a collapse of the intervertebral disc space, and magnetic resonance imaging showed disc herniation of L3-4.

CONCLUSIONS

Disc herniation even in solid fused segments may occur. Removal of pedicle screws and cranial extension of interbody fusion may increase the intradiscal stress associated with physiologic cantilever motion of the disc.

Clinical Significance of Preoperative Embolization for Non-Hypervascular Metastatic Spine Tumors

OBJECTIVE

The efficacy of preoperative embolization for hypervascular metastatic spine disease (MSD) such as renal cell and thyroid cancers has been reported. However, the debate on the efficacy of preoperative embolization for non-hypervascular MSD still remains unsettled. The purpose of this study is to determine whether preoperative embolization for non-hypervascular MSD decreases perioperative blood loss.

METHODS

A total of 79 patients (36 cases of preoperative embolization and 43 cases of non-embolization) who underwent surgery for metastatic spine lesions were included. Representative hypervascular tumors such as renal cell and thyroid cancers were excluded. Intraoperative and perioperative estimated blood losses (EBL), total number of transfusion and calibrated EBL were recorded in the embolization and non-embolization groups. The differences in EBL were also compared along with the type of surgery. In addition, the incidence of Adamkiewicz artery and complications of embolization were assessed.

RESULTS

The average age of 50 males and 29 females was 57.6±13.5 years. Lung (30), hepatocellular (14), gastrointestinal (nine) and others (26) were the primary cancers. The demographic data was not significantly different between the embolization and the non-embolization groups. There were no significant differences in intraoperative EBL, perioperative EBL, total transfusion and calibrated EBL between two groups. However, intraoperative EBL and total transfusion in patients with preoperative embolization were significantly lower than in non-embolization in the corpectomy group (1645.5 vs. 892.6 mL, p=0.017 for intraoperative EBL and 6.1 vs. 3.9, p=0.018 for number of transfusion). In addition, the presence of Adamkiewicz artery at the index level was noted in two patients. Disruption of this major feeder artery resulted in significant changes in intraoperative neuromonitoring.

CONCLUSION

Preoperative embolization for non-hypervascular MSD did not reduce perioperative blood loss. However, the embolization significantly reduced intraoperative bleeding and total transfusion in corpectomy group. Moreover, the procedure provided insights into the anatomy of tumor and spinal cord vasculature.

Delayed bilateral facet dislocation at L4-5: A case report

RATIONALE

Traumatic bilateral facet dislocation in the lumbar (L) spine has rarely been reported. All reported cases were presented with acute facet dislocation. However, we present the first case of delayed bilateral facet dislocation at L4-5.

PATIENT CONCERNS

A 34-year-old woman presented with back pain after a head-on collision. The patient was treated conservatively for 3 months with rigid orthosis and activity restriction. Even after this conservative treatment, she continued to suffer from persistent back pain that radiated down her left leg and a progressively kyphotic posture.

DIAGNOSES

Initial imaging studies revealed a fracture of the left L5 superior articular process with a posterior ligament complex (PLC) injury. Subsequent radiographs showed the locked facet dislocation with kyphotic changes.

INTERVENTIONS

The patient underwent surgical reduction and fusion, and the operative findings revealed the L4-5 bilateral facet dislocation and rupture of the PLC at the index level.

OUTCOMES

After surgical reduction and fusion at L4-5 by posterior interbody fusion, we achieved a satisfactory clinical outcome.

LESSONS

Injury of the PLC in the lower lumbar region deserves careful attention for the development of sequelae. The anatomic transition from lordosis to kyphosis, in the lumbosacral region may be related to this type of injury.

Use of supplemental anti-HBc testing of donors showing non-discriminating reactive results in multiplex nucleic acid testing

BACKGROUND AND OBJECTIVES

The Korean Red Cross began nucleic acid amplification testing (NAT) for HIV and HCV in February 2005, and added HBV NAT beginning in June 2012. The current NAT system utilizes a multiplex assay for simultaneous detection of HBV DNA, HCV RNA and HIV-1 RNA. For samples that are reactive in the multiplex assay, we do specific tests for each virus. However, there have been cases of non-discriminated reactive (NDR) results which appear to be the result of non-specific reactions or cross-contamination, although some cases are considered to arise from the presence of low levels of HBV DNA due to occult hepatitis B infection.

MATERIALS AND METHODS

We examined the incidence of NDR results in previous donations of some NAT-reactive donors. Additionally, for those donors with NDR results, we performed an HBV core antibody (anti-HBc) assay.

RESULTS

From November 2015 to March 2016, there were 408 NAT-reactive donors. Of these, nineteen HBV NAT-reactive donors showed a history of NDR results in the past donations. Seven donors showed NDR results more than once. Of 771 NDR donors, 362 (47·0%) were anti-HBc reactive.

CONCLUSION

The NDR donors had a substantially higher rate of anti-HBc reactivity than other blood donors indicating that some with anti-HBc reactivity represent donors with occult HBV. Therefore, the incorporation of an anti-HBc testing for NDR donors could improve blood safety testing for the Korean Red Cross.

Arthroscopic-assisted plate fixation for displaced large-sized comminuted greater tuberosity fractures of proximal humerus: a novel surgical technique

PURPOSE

The purpose of the present study was to describe the use of a novel hybrid surgical technique-arthroscopic-assisted plate fixation-and evaluate its clinical and anatomical outcomes in the management of large, displaced greater tuberosity (GT) fractures with comminution.

METHODS

From 2009 to 2011, this novel technique was performed in 11 patients [2 men and 9 women; median age, 64 years (range 41-83 years)] with large, comminuted GT fractures, with fragment displacements of >5 mm. The preoperative mean posterior and superior migration of the fractured fragment, as measured on computed tomography (CT), was 19.5 and 5.5 mm, respectively. Two patients had shoulder fracture-dislocation, and three had associated undisplaced surgical neck fracture. The mean duration between injury and surgery was 4 days. The mean follow-up duration was 26 months.

RESULTS

At the final follow-up, the mean postoperative ASES, UCLA and SST scores were 84, 29, and 8, respectively. The mean range of motion was as follows: forward flexion, 138°; abduction, 135°; external rotation at the side, 19°; and internal rotation, up to the L2 level. The mean posterior and superior displacements of fracture fragments on postoperative CT scan [0.7 ± 0.8 mm (range 0-2.1 mm) and 2.8 ± 0.5 mm (range 3.4-5.3 mm), respectively] were significantly improved (p < 0.05). On arthroscopy, a partial articular-side supraspinatus tendon avulsion lesion was identified in 10 of 11 patients (91 %), and 1 of these patients had a partial tear of the biceps and 1 had a partial subscapularis tear, respectively (9 %). Intraoperatively, 1 anchor pullout and 1 anchor protrusion through the humeral head were noted and corrected. Postoperatively, the loss of reduction in the fracture fragment was noted in 1 patient at 4 weeks, after corrective reduction and fixation surgery.

CONCLUSIONS

The novel arthroscopic-assisted anatomical plate fixation technique was found to be effective in reducing large-sized, displaced, comminuted GT fractures and in allowing concurrent management of intra-articular pathologies and early functional rehabilitation. Compared with the conventional plate fixation or arthroscopic suture anchor fixation technique, arthroscopic-assisted plate fixation enabled accurate restoration of the medial footprint of the GT fracture and provided an effective buttress to the large-sized GT fracture fragments.

LEVEL OF EVIDENCE

Retrospective clinical study, Level IV.

Clinical and radiological outcomes of unstable proximal humeral fractures treated with a locking plate and fibular strut allograft

PURPOSE

To evaluate the clinical and radiological outcomes of unstable proximal humeral fractures (PHFs) treated with a locking plate and fibular strut allograft.

METHODS

This study included 36 patients [7 men, 29 women; mean age, 68 years (range, 22-94 years)] with unstable PHFs with medial column disruption. All patients were treated with open reduction and internal fixation using a locking plate and fibular strut allograft. Post-operative assessment included clinical outcomes, shoulder range of motion, radiographic examination, and any complications. Post-operative radiological assessment including the humerus neck-shaft angle (NSA) and the humeral head height was performed.

RESULTS

At the mean two year follow-up visit, the mean American Shoulder and Elbow Society (ASES) and University of California, Los Angeles (UCLA) scores were 77 and 28, respectively. According to the UCLA rating scale, the result was excellent in six, good in 20, fair in six, and poor in four cases. According to the Paavolainen method, 31 patients had good results with an NSA of 130 ± 10°; three patients showed fair results with an NSA of 100-120°, and two patients experienced a poor result with an NSA of <100°. When calculating the humeral head height, the mean loss of reduction was measured as 1.6 mm (from 10.8 or 9.2 mm). Varus collapse and avascular necrosis of the humeral head was noted in two patients for each condition.

CONCLUSIONS

For unstable proximal humerus fractures, particularly in elderly patients with severe osteoporosis or in younger patients with a four-part fracture, locking plate fixation with a fibular strut allograft provided rigid medial support and showed satisfactory clinical and radiological outcomes.

Synthesis, Crystal Structure, Characterization, and Catalytic Properties of TNU-9

The synthesis, crystal structure, characterization, and catalytic properties of the novel medium-pore zeolite TNU-9 (framework type TUN), one of the most crystallographically complex zeolites known to date, are described. TNU-9 was found to crystallize under hydrothermal conditions at the expense of a lamellar precursor over a very narrow range of SiO(2)/Al(2)O(3) and NaOH/SiO(2) ratios and in the presence of 1,4-bis(N-methylpyrrolidinium)butane and Na+ ions as structure-directing agents. A combination of molecular modeling and Rietveld refinement using synchrotron powder diffraction data confirms the proposed topology of as-made TNU-9 and suggests three or possibly four different sites for the organic within the complex pore structure. The proton form (H-TNU-9) of this new medium-pore zeolite exhibits exceptionally high hydrothermal stability, as well as very strong acidity. When compared to H-ZSM-5, H-MCM-22, H-mordenite, and H-Beta, H-TNU-9 displays unique shape selectivities for the acid-catalyzed reactions of monoaromatic hydrocarbons such as the disproportionation of toluene and the isomerization and disproportionation of m-xylene. In particular, for the isomerization of m-xylene, the ratio of isomerization to disproportionation increases steadily to values in excess of 50 with prolonged time on stream and a high p/o xylene ratio is observed in the products, achieving a value of ca. 6 after only a short time on stream. These results are rationalized on the basis of the unique pore topology of TNU-9.

Prevention of postoperative sore throat using capsicum plaster applied at the Korean hand acupuncture point

In a randomised, double-blind, sham-controlled study, we compared the efficacy of capsicum plaster (PAS) applied at the Korean hand acupuncture point for the prevention of postoperative sore throat in 150 patients scheduled to undergo abdominal hysterectomy. The K group had PAS applied at the K-A20 of both hands and placebo tape at both non-acupoints. The PAS was applied prior to induction of anaesthesia and removed 8 h postoperatively. The sore throat scores of Group K were significantly lower than those of other groups at 24 h following surgery (p = 0.00027). The prevalence of moderate to severe sore throat at 24 h was lower for Group K (0%) than for sham and placebo controls (16%[p = 0.038] and 19%[p = 0.032], respectively). There were no differences in the recovery room of the sore throat scores for all groups. We found that the PAS applied at the K-A20 was an alternative method for reducing postoperative sore throat.

Surface measurements of global warming causing atmospheric constituents in Korea

The expansion of the industrial economy and the increase of population in Northeast Asian countries have caused much interest in climate monitoring related to global warming. However, new techniques and better platforms for the measurement of global warming and regional databases are still old-fashioned and are not being developed sufficiently. With respect to this agenda, since 1993, at the request of the World Meteorological Organization (WMO), to monitor functions of global warming, the Korea Meteorological Administration (KMA) has set up a Global Atmospheric Watch (GAW) Station on the western coast of Korea (Anmyun-do) and has been actively monitoring global warming over Northeast Asia. In addition, atmospheric carbon dioxide (CO2) has been measured for a similar KMA global warming program at Kosan, Cheju Island since 1990. Aerosol and radiation have also been measured at both sites as well as in Seoul. The observations have been analyzed using diagnostics of climate change in Northeast Asia and also have been internationally compared. Results indicate that greenhouse gases are in good statistic agreement with the NOAA/Climate Monitoring and Diagnostics Laboratory (CMDL) long-term trends of monthly mean concentrations and seasonal cycles. Atmospheric particulate matter has also been analyzed for particular Asian types in terms of optical depth, number concentration and size distribution.

Human mouse mast cell protease 7-like tryptase genes are pseudogenes

BACKGROUND

Alpha-tryptase and beta-tryptase are important clinical markers for mast cell-dependent disorders. A third family of tryptase genes on human chromosome 16 has been identified and called human mouse mast cell protease 7 (hmMCP-7)-like tryptase.

OBJECTIVE

This study was designed to determine whether these tryptase genes are expressed by human mast cells.

METHODS

A 2842-bp hmMCP-7-like tryptase gene was cloned and sequenced from a human placental genomic library. PCR and RT-PCR procedures, respectively, were used to determine whether this tryptase gene family was present in most genomes and whether it was expressed.

RESULTS

The tryptase clone was almost identical to the hmMCP-7-like tryptase II and I genes, and therefore it was called hmMCP-7-like tryptase III. All such genes encode a Gln(-3) like alpha-tryptase. They also terminate translation after amino acid 235, whereas alpha- and beta-tryptase genes each encode a 275-amino acid protein. In this study, cell lines HMC-1, KU812, and Mono-Mac-6; mast cells derived in vitro from cord blood and fetal liver progenitors; and mast cell-enriched preparations of dispersed skin and lung cells contained hmMCP-7-like tryptases in their genomes by PCR with gene-specific primers. To identify whether such genes were transcriptionally active, RT-PCR revealed alpha- or beta-tryptase products in all mast cell preparations and cell lines and in activated skin-derived mast cells, but no hmMCP-7-like tryptase products.

CONCLUSION

These results indicate hmMCP-7-like tryptase (I, II, III) genes are pseudogenes and unlikely to affect measurements of alpha- and beta-tryptases.

An improved procedure for the development of human mast cells from dispersed fetal liver cells in serum-free culture medium

The in vitro development of human mast cells from fetal liver cells with recombinant human stem cell factor in serum-containing RPMI was compared to that in AIM-V media with and without serum. Compared to serum-containing media, AIM-V medium caused mast cells to develop earlier and in greater numbers. By 2 weeks, about 60% of cells in serum-free AIM-V medium were phenotypic mast cells, approximately 2 times the percentages in serum-containing media. By 6 weeks the percentages of mast cells were > or =80% under all conditions, but the number of mast cells was 3-4-fold greater in serum-free AIM-V medium than in serum-supplemented media. Mast cells obtained in serum-free AIM-V medium exhibited rounded nuclei, like tissue-derived mast cells; mast cells obtained in serum-supplemented media had segmented nuclei. By 10-12 weeks of culture about 40% of the AIM-V-derived cells showed strong chymase immunocytochemical staining, a pattern observed for only 14% of the cells in serum-containing media. AIM-V medium is a suitable medium for the development of human mast cells in vitro, and permits an earlier, more selective and greater expansion of mast cells than serum-containing media.

Laser soldering and welding for ossicular reconstruction: an in vitro test

To evaluate the possibility of laser application in ossicular reconstruction, soldering and welding of bony tissue with proteineous materials was performed by using a CO (2) laser, and the bonding strength of these materials was measured with a gradual weighing system. The soldered and welded surface of bone was observed with a scanning electron microscope. Additionally, welding of human ossicles and synthetic materials was experimentally tried with lasers, and morphologic changes were observed and recorded. A scanning electron microscopic examination was also done. A 40% albumin solution and commercial fibrin glue showed the best bonding strength. Bridging of denatured protein solder may be a mechanism of bonding. Polycel was melted by using a laser beam, and melted Polycel covered the surface of the ossicle. However, the bonding strength was not enough to use, and exact measurement of bonding strength was not possible. These results suggested the possibility of laser soldering and welding in ossicular reconstruction, especially with ossicle or cortical bone.

Laser Soldering and Welding for Ossicular Reconstruction: An in Vitro Test

To evaluate the possibility of laser application in ossicular reconstruction, soldering and welding of bony tissue with proteineous materials was performed by using a Co2 laser, and the bonding strength of these materials was measured with a gradual weighing system. The soldered and welded surface of bone was observed with a scanning electron microscope. Additionally, welding of human ossicles and synthetic materials was experimentally tried with lasers, and morphologic changes were observed and recorded. A scanning electron microscopic examination was also done. A 40% albumin solution and commercial fibrin glue showed the best bonding strength. Bridging of denatured protein solder may be a mechanism of bonding. Polycel was melted by using a laser beam, and melted Polycel covered the surface of the ossicle. However, the bonding strength was not enough to use, and exact measurement of bonding strength was not possible. These results suggested the possibility of laser soldering and welding in ossicular reconstruction, especially with ossicle or cortical bone.

Combined analysis of germline polymorphisms of p53, GSTM1, GSTT1, CYP1A1, and CYP2E1: relation to the incidence rate of cervical carcinoma

BACKGROUND

The authors established the genotype frequencies of cytochrome P450 (CYP1A1/MspI, CYP2E1/PstI, and CYP2E1/DraI), glutathione-S-transferase (GSTM1 and GSTT1), and p53 (exon 4/AcclI and intron 3/16-base pair duplication) gene polymorphisms in cervical carcinoma patients and controls and evaluated the association between the specific genotype or genotype combinations of these polymorphisms and the risk of cervical carcinoma.

METHODS

In this case-control study, the genotypes of 181 human papillomavirus (HPV)-16 or HPV-18 positive cervical carcinoma patients and 1-to-1 age-matched controls were determined using a polymerase chain reaction-based technique.

RESULTS

Among these polymorphisms, the individuals carrying arginine/proline genotypes of p53 showed a 9.5-fold increase of cervical carcinoma risk (95% confidence interval [CI], 4.9-18.6) compared with those individuals carrying arginine/arginine genotypes. The frequency of overall GSTT1 null genotypes also was significantly higher in cervical carcinoma patients compared with that of GSTT1 positive genotypes (P = 0.003; odds ratio [OR] = 1.9; 95% CI, 1.2-2.9). The genotype combination of p53 and GST played a more important role in describing the relative risk of cervical carcinoma. The individuals carrying both the arginine/proline genotype of p53 and the null genotype of GSTT1 showed a 3.5-fold increase of cervical carcinoma risk (95% CI, 1.8-7.1) compared with those individuals carrying both the arginine/arginine genotype of p53 and the GSTT1 positive genotype. In the patients who were stratified into the two age groups, the null genotypes of GSTT1 (69.1% vs. 45.5%; P = 0.016) and GSTM1 (61.8% vs. 40.0%; P = 0.028) in cervical carcinoma were significantly overrepresented in the younger age subgroup (age 40 years or younger) compared with those of controls. Especially in this age group, the individuals carrying both null genotypes of GSTT1 and GSTM1 showed a 17.8-fold increase of cervical carcinoma risk (95% CI, 2.2-141.0) compared with the individuals carrying both positive genotypes of GSTT1 and GSTM1.

CONCLUSIONS

The results of the current study suggested that the arginine/proline genotype of p53, independently or in conjunction with the GSTT1 null genotype, could affect the genetic susceptibility for cervical carcinoma, and HPV positive women carrying both null genotypes of GSTT1 and GSTM1 have an increased risk of cervical carcinoma developing before age 40 years.

Combined analysis of germline polymorphisms of p53, GSTM1, GSTT1, CYP1A1, and CYP2E1: relation to the incidence rate of cervical carcinoma

BACKGROUND

The authors established the genotype frequencies of cytochrome P450 (CYP1A1/MspI, CYP2E1/PstI, and CYP2E1/DraI), glutathione-S-transferase (GSTM1 and GSTT1), and p53 (exon 4/AcclI and intron 3/16-base pair duplication) gene polymorphisms in cervical carcinoma patients and controls and evaluated the association between the specific genotype or genotype combinations of these polymorphisms and the risk of cervical carcinoma.

METHODS

In this case-control study, the genotypes of 181 human papillomavirus (HPV)-16 or HPV-18 positive cervical carcinoma patients and 1-to-1 age-matched controls were determined using a polymerase chain reaction-based technique.

RESULTS

Among these polymorphisms, the individuals carrying arginine/proline genotypes of p53 showed a 9.5-fold increase of cervical carcinoma risk (95% confidence interval [CI], 4.9-18.6) compared with those individuals carrying arginine/arginine genotypes. The frequency of overall GSTT1 null genotypes also was significantly higher in cervical carcinoma patients compared with that of GSTT1 positive genotypes (P = 0.003; odds ratio [OR] = 1.9; 95% CI, 1.2-2.9). The genotype combination of p53 and GST played a more important role in describing the relative risk of cervical carcinoma. The individuals carrying both the arginine/proline genotype of p53 and the null genotype of GSTT1 showed a 3.5-fold increase of cervical carcinoma risk (95% CI, 1.8-7.1) compared with those individuals carrying both the arginine/arginine genotype of p53 and the GSTT1 positive genotype. In the patients who were stratified into the two age groups, the null genotypes of GSTT1 (69.1% vs. 45.5%; P = 0.016) and GSTM1 (61.8% vs. 40.0%; P = 0.028) in cervical carcinoma were significantly overrepresented in the younger age subgroup (age 40 years or younger) compared with those of controls. Especially in this age group, the individuals carrying both null genotypes of GSTT1 and GSTM1 showed a 17.8-fold increase of cervical carcinoma risk (95% CI, 2.2-141.0) compared with the individuals carrying both positive genotypes of GSTT1 and GSTM1.

CONCLUSIONS

The results of the current study suggested that the arginine/proline genotype of p53, independently or in conjunction with the GSTT1 null genotype, could affect the genetic susceptibility for cervical carcinoma, and HPV positive women carrying both null genotypes of GSTT1 and GSTM1 have an increased risk of cervical carcinoma developing before age 40 years.

Characterization of amiodarone metabolites and impurities using liquid chromatography/atmospheric pressure chemical ionization mass spectrometry

Using the high performance liquid chromatography/atmospheric pressure chemical ionization tandem mass spectrometry (HPLC/APCI-MS/MS) technique, together with established trends from the literature, the structures of metabolites and impurities of amiodarone, an anti-arrhythmic drug, have been assigned. By comparing analyses of products of incubation with rat liver microsomes with controls in which glucose 6-phosphate dehydrogenase was omitted, metabolites could be distinguished from impurities. Structures for the two proposed metabolites and four impurities are proposed.

Determination of homocysteine and its related compounds by solid-phase microextraction-gas chromatography-mass spectrometry

The purpose of this study was to develop a simple and accurate analytical method to determine homocysteine (Hcy), cysteine (Cys), and methionine (Met) in aqueous samples. Until now, the most frequently used method for the assay of Hcy, Cys, and Met has been high-performance liquid chromatography with fluorescence detection after fluorescent tagging. The newly developed method involves the employment of the SPME (solid-phase microextraction) technique together with GC-MS. For application to a gas chromatographic system, alkyl formate derivatives were prepared in the form of N(O,S)-alkoxycarbonyl alkyl ester with the analytes in the aqueous samples. The optimum derivatizing regent for N(O,S)-alkoxycarbonyl alkyl ester was chosen by comparing the efficiency of the derivatized analytes in a GC through the SPME method and liquid-liquid extraction. The optimum conditions of the SPME system for the analytes derivatized with N(O,S)-ethoxycarbonyl propyl ester in the aqueous matrix were pH 3.0 and no salt, and 30 min equilibration time using an 85 microm PA (polyacrylate) fiber. The developed method is inexpensive, easy and rapid.

Identification of IY81149 and its metabolites in the rat plasma using the on-line HPLC/ESI mass spectrometry

Reversed-phase high-performance liquid chromatography/mass spectrometry (HPLC/MS) with an electrospray ionization (ESI) interface was applied to the identification of metabolites of IY 81149 in the rat plasma. Fragments obtained using collision-induced dissociation (CID) in both positive and negative modes were utilized to elucidate the structure of metabolites. The eluent from the conventional HPLC column was split and directly introduced into an ESI-mass spectrometer for the identification of the structures. The CID technique allowed the sensitive identification of sulfonyl-IY81149 and hydroxy-IY81149 from the rat plasma.

Lack of an intronic Sp1 binding-site polymorphism at the collagen type I alpha1 gene in healthy Korean women

Osteoporosis is a disease that is strongly genetically influenced. However, the genes responsible for the disease are poorly defined. Recent data show that a G-T transition polymorphism of the Sp1 binding site at the collagen type I alpha1 gene (Sp1 polymorphism) is associated significantly with bone mineral density (BMD) and osteoporotic fracture in British women. To establish the association between the Sp1 genotypes and BMD in Korean women, we examined 200 healthy postmenopausal women of Korean ethnicity, ranging in age from 44 to 66 years (mean+/-SD: 54.7+/-5.3 years). PCR amplification using the same primers as those used previously, with enzyme digestion, revealed no restriction site in our samples. We also performed a single-strand conformational polymorphism (SSCP) analysis in 100 of the 200 samples and could not find any polymorphic sites in the PCR amplification region. Based on our study, the Sp1 polymorphism at the type I collagen alpha1 gene was not found in Korean women. Therefore, we suggest that the Sp1 polymorphism at the type I collagen alpha1 gene is absent or rare in Korean women. Based on the present findings, this polymorphism does not seem to be responsible for the entire genetic contribution to BMD.

Determination of amphetamine, methamphetamine and dimethamphetamine in human urine by solid-phase microextraction (SPME)-gas chromatography/mass spectrometry

A simple and rapid assay method for three stimulant drugs (amphetamine, methamphetamine, and dimethamphetamine) in human urine using solid-phase microextraction was developed. In solid-phase microextraction, the drugs were equilibrated between the adsorbent coated-fiber and aqueous sample matrix. After adsorption of the analytes, the fiber was directly transferred to the injector of a gas chromatograph, where the analytes were thermally desorbed and subsequently separated by the gas chromatograph and detected by mass spectrometer. The solid-phase microextraction method, which did not require solvents, was found to be a fast and simple analytical method. We optimized the solid-phase microextraction technique, for factors such as the NaCl salt effect (30%), pH effect (pH=12.4), equilibration time (30 min), desorption time (1 min) and coated-fiber type (100 microm poly(dimethylsiloxane)) and detected the stimulants in human urine, obtained from human subjects. The detection limits of each drug were below 1-10 ng/ml. The developed method can be applied to the abused drug test.

Short stature in Korean women: a contribution to the multifactorial predisposition to gestational diabetes mellitus

We examined the associations between demographic characteristics including short stature and the prevalence of gestational diabetes mellitus (GDM) in Korean women. In this study, a total of 9005 pregnant women underwent universal screening for GDM. Oral glucose tolerance tests (100 g OGTT) were performed in positive screenees (1 h plasma glucose > or = 7.2 mmol/l) and GDM was diagnosed using National Diabetes Data Group criteria. Women with GDM were older and heavier than those with a positive screen and normal OGTT, as well as those with a negative screen. However, height of women with GDM was significantly shorter than those with a positive screen and normal OGTT, and a negative screen. When the study subjects were stratified according to height quartiles, the plasma glucose at the screening test decreased as height increased. Furthermore, the prevalence of GDM was highest in the shortest quartile (< or = 157 cm) group; the odds ratio for GDM was two times greater compared with the highest quartile (> or = 163 cm) group, even after controlling for age and body mass index (BMI). In addition, multiple logistic regression analysis revealed that greater prepregnancy BMI, age, weight gain, a parental history of diabetes mellitus, and shorter maternal height were directly and independently associated with the prevalence of GDM. We have found that short stature is an independent risk factor for GDM in the racially homogeneous population of Seoul, Korea. It is suggested that this propensity may be conveyed primarily by environmental influences. However, genetic factors may also modify the response to the environmental insult. Our findings also emphasize the heterogeneity of factors which predispose to GDM.

Squamous cell carcinoma of the tonsil--clinical features and treatment results

Squamous cell carcinoma of the tonsil has a relatively poor prognosis. Aggressive surgery, radiation therapy and combinations of irradiation and surgery have been employed but there exists some controversy about the efficacy of these treatment modalities. The purpose of this paper is to compare the efficacy of treatment between the surgery followed by radiation therapy and the preoperative radiation therapy followed by surgical resection. The medical records of 33 patients treated for squamous cell carcinoma of the tonsil at the Department of Otolaryngology-Head and Neck Surgery, Korea University Hospital between 1989-1993 were reviewed retrospectively. None of the patients were stage I, but stage II, III, and IV were four, five, and 24 patients, respectively. There were 30 males and three females. The most common histopathology was moderately differentiated squamous cell carcinoma (20/33). The 13 patients treated initially with surgery had an overall three-year survival rate of 38.5%, and the rate for the 20 patients treated initially with radiation was 40%. The main pattern of treatment failure was a local recurrence and neck metastases, and pathologic differentiation thought to be an important prognostic factor. Complications are fewer in patients treated initially with surgery (23.1%) than patients initially treated with radiation (50.0%). There is no difference in the efficacy between the two therapeutic groups.

Nonassociation of estrogen receptor genotypes with bone mineral density and estrogen responsiveness to hormone replacement therapy in Korean postmenopausal women

Hormone replacement therapy (HRT) prevents bone loss in postmenopausal women, but some women are resistant to therapy. A recently reported case of severe estrogen resistance caused by a germline mutation at the estrogen receptor (ER) gene locus suggests the possibility that other variants of the ER gene could be responsible for resistance to HRT and could also be an answer to the heritable components of bone density. Three restriction fragment length polymorphisms (RFLPs) at the ER gene locus, represented as BstUI (or B variant), PvuII, and XbaI, and their relationship to bone mineral density (BMD) and estrogen responsiveness to HRT were examined in 248 healthy postmenopausal women, aged 41-68 yr (mean +/- SD, 52.0 +/- 4.6 yr) in Korea. The BstUI restriction site was not found in Korean women. The distribution of the PvuII and XbaI RFLPs was as follows: PP, 35 (14.1%); Pp, 136 (54.8%); pp, 77 (31.1%) and XX, 18 (7.3%); Xx, 72 (29.0%); and xx, 158 (63.7%), respectively (capital letters signify the absence of and lower case letters signify the presence of the restriction site of each RFLP). There was no significant relation between ER genotypes and z score values of lumbar spine BMD. Also, no significant genotypic differences were found in the change in lumbar spine BMD and those in biochemical markers before and after 1 yr of HRT. These data indicate no significant effects of ER genotypes on BMD and estrogen responsiveness after HRT.

Effects of anti-IgE mAb on serum IgE, Fc epsilon RII/CD23 expression on splenic B cells and worm burden in mice infected with Paragonimus westermani

It is generally accepted that parasite-specific IgE plays a crucial role in host defense against helminthic parasites. However, the role of high levels of nonspecific IgE in helminthic infections is still controversial. To investigate the role of nonspecific IgE in primary infections with P. westermani, the effect of anti-IgE mAb treatment on serum IgE, Fc epsilon RII/CD23 expression and worm burden in Paragonimus-infected mice were examined. In mice treated with anti-IgE antibody, the total IgE levels were not detectable (1 microgram/ml) throughout the experiment compared with untreated infected mice. The mean percentages of Fc epsilon RII/CD23 positive splenic B cells in anti-IgE treated mice (range: 20.3 - 30.5) were also decreased throughout the experiment compared with untreated infected mice (range: 35.7 - 44.4). Reduction of the total IgE and expression of Fc epsilon RII/CD23 on splenic B cells resulted in decreased worm burden six weeks post infection. These results suggest that high levels of nonspecific IgE in mice with primary infections of P. westermani play a harmful, rather than beneficial, role for the host, perhaps by interfering with CD23-dependent cellular pathways.

Past and current obesity in Koreans with non-insulin-dependent diabetes mellitus

To determine the prevalence of past and current obesity among patients with non-insulin-dependent diabetes mellitus (NIDDM) and to define the clinical characteristics of non-obese NIDDM patients in South Korea, we studied a cross-section of 749 NIDDM patients and a group of age- and sex-matched control subjects. Current height, weight and waist-to-hip ratio (WHR), the history of weight changes and the family history of diabetes were recorded. Obesity was defined as body mass index (BMI) > 25 kg/m2. The maximum lifetime BMI of diabetic patients was significantly higher than that of control subjects (P < 0.001). Compared with control subjects, current BMI was higher in diabetic women (P < 0.001) but not in diabetic men. In contrast, WHR of both diabetic men and women were significantly higher than those of controls (P < 0.05). BMI and WHR correlated significantly with fasting C-peptide levels and log-triglyceride levels in NIDDM patients. As a whole, 72% of the South Korean NIDDM patients had a history of past obesity as assessed by their maximum weight, while only 38% of them were currently obese. Compared with obese patients, non-obese patients were characterized by lower fasting serum C-peptide levels (P < 0.001), a higher percentage of insulin treatment (P < 0.05), lower maximum BMI (P < 0.001) and more pronounced weight loss from the time at their maximum weight (P < 0.001). In summary, increased upper body adiposity and a history of past obesity were associated with NIDDM in South Korea. Although most South Korean NIDDM patients were previously obese, many of them were currently not obese. Lower maximum BMI, lower serum C-peptide levels and a higher percentage of insulin treatment in non-obese NIDDM patients suggest that the capacity to increase insulin secretion in response to increasing weight gain is rather limited in these patients.

Non-insulin-dependent diabetes mellitus (NIDDM) in Korea

The prevalence of diabetes mellitus in Korea has increased tremendously during the past several decades. In addition to the explosive increase of diabetes mellitus, the clinical characteristics of diabetes mellitus in Korea seems to be quite different from those of Western countries. Most patients with non-insulin-dependent diabetes mellitus (NIDDM) are non-obese and many of them lose weight significantly during the course of developing diabetes. The pathogenic mechanism(s) underlying this phenotype is still unclear. A subgroup of patients known as slow onset IDDM exists, but this could not explain the majority of non-obese NIDDM in Korea. In order to examine whether insulin resistance/hyperinsulinaemia is important in the development of NIDDM we conducted the following studies. Fasting plasma glucose and insulin concentration were measured in subjects with normal glucose tolerance, impaired glucose tolerance and diabetes mellitus. The peak plasma insulin level was much lower than that of Pima Indians or Caucasians. We also found that the insulin sensitivity index measured by euglycemic hyperinsulinaemic clamp in the first degree relatives of Korean NIDDM patients was not lower than that in a control group. This data suggests that insulin resistance, or hyperinsulinaemia, does not play a major role in the development of NIDDM in Korea. Taken together with the rarity of obese NIDDM in Korea, it maybe suggested that the insulin secretory capacity of Korean people being smaller than Western people they cannot compensate for the insulin resistance imposed by recent changes in life style.