Biomedical subjects

H S Kim

Publications and source records attributed to H S Kim.

At least 37 records · Page 2Linked to original sources

PubMed2005

Usefulness of the carina as a radiographic landmark for central venous catheter placement in paediatric patients.

BACKGROUND: Several reports have proposed radiographic landmarks for the proper positioning of central venous catheters (CVC). The carina is one of the proposed landmarks in adults. Here, we evaluate the possibility of using the carina as a radiographic landmark for the identification of proper positioning of the CVC tip in paediatric patients. METHODS: We studied 57 right internal jugular vein catheterizations in infants and children undergoing surgery for the treatment of congenital heart disease. After placing the CVC tip at the junction of the superior vena cava and the right atrium (SVC-RA junction) via intraoperative transoesophageal echocardiography, and by taking postoperative anterior-posterior chest radiographs, we measured the longitudinal distance from the carina to the SVC-RA junction, using the Picture Archiving and Communicating System. RESULTS: The average distance between the carina and the SVC-RA junction was 1.5 cm (95% CI 1.3-1.8 cm). No catheter tip was above the carina. Although there was no particular relationship between this distance and the patient's age, height, or weight, the distance between the carina and the SVC-RA junction tended to be more variable in younger and smaller children. CONCLUSIONS: The carina can be used as a radiographic landmark for the proper CVC tip placement in paediatric patients. If the tip of the CVC is not distal to the carina the chances are minute that it is in the right atrium.

Adolescent↗

PubMed2005

Correlation of bispectral index with end-tidal sevoflurane concentration and age in infants and children.

BACKGROUND: The bispectral index (BIS) has been evaluated as a tool for measuring depth of anaesthesia, but the use of BIS in a paediatric population is still controversial. This study was designed to evaluate the correlation of BIS with end-tidal sevoflurane concentration and age in infants and children. METHODS: Eighty-one patients undergoing elective urology surgery were allocated into three age groups; 6 months to 2 yr (n=28), 3-7 yr (n=33), and 8-12 yr (n=20). Sevoflurane was administered to achieve steady-state end-tidal sevoflurane concentrations (ET(sevo)) of 2.0, 3.0, and 4.0%; these were achieved consecutively either from the lowest or from the highest concentration. The BIS (version XP) was monitored continuously. RESULTS: In all three groups, BIS decreased significantly when ET(sevo) increased from 2.0 to 3.0% but there was a paradoxical increase in BIS values when ET(sevo) increased from 3.0 to 4.0%. The non-linear regression analysis showed a significant correlation between BIS and age at each ET(sevo). The younger patients showed the higher BIS values. CONCLUSIONS: In children aged 6 months to 12 yr, the BIS increased paradoxically as ET(sevo) increased from 3.0 to 4.0%. BIS values showed a wide variation in the same ET(sevo) and the age itself was considered to be a factor affecting the BIS values.

Aging↗

PubMed2005

Transfusion for a patient of cis-AB blood type undergoing a redo cardiac operation.

cis-AB, a rare ABO genotype, is the result of a mutated gene resulting in dual specific hybrid enzymes. A single-point mutation reverses the specificity of human blood group B synthesizing galactosyltransferase. This may lead to misclassification in ABO grouping and adverse transfusion reactions. Recently, the authors experienced a case of a patient with cis-AB blood type undergoing pulmonary valve replacement and tricuspid valvuloplasty. We transfused the patient with Rh+ A packed red blood cell, fresh frozen plasma and platelet concentrates without any clinically significant transfusion reactions.

ABO Blood-Group System↗

PubMed2005

The analysis of telomere length and telomerase activity in cloned pigs and cows.

Inefficiency in the production of cloned animals is most likely due to epigenetic reprogramming errors after somatic cell nuclear transfer (SCNT). In order to investigate whether nuclear reprogramming restores cellular age of donor cells after SCNT, we measured telomere length and telomerase activity in cloned pigs and cattle. In normal pigs and cattle, the mean telomere length was decreased with biological aging. In cloned or transgenic cloned piglets, the mean telomere length was elongated compared to nuclear donor fetal fibroblasts and age-matched normal piglets. In cloned cattle, no increases in mean telomere length were observed compared to nuclear donor adult fibroblasts. In terms of telomerase activity, significant activity was observed in nuclear donor cells and normal tissues from adult or new-born pigs and cattle, with relatively higher activity in the porcine tissues compared to the bovine tissues. Cloned calves and piglets showed the same level of telomerase activity as their respective donor cells. In addition, no difference in telomerase activity was observed between normal and transgenic cloned piglets. However, increased telomerase activity was observed in porcine SCNT blastocysts compared to nuclear donor cells and in vitro fertilization (IVF)-derived blastocysts, suggesting that the elongation of telomere lengths observed in cloned piglets could be due to the presence of higher telomerase activity in SCNT blastocysts. In conclusion, gathering from the comparative studies with cattle, we were able to demonstrate that telomere length in cloned piglets was rebuilt or elongated with the use of cultured donor fetal fibroblasts.

Animals↗

PubMed2005

Primary colon lymphoma in Korea: a KASID (Korean Association for the Study of Intestinal Diseases) Study.

Although almost all primary colorectal lymphomas are of B-cell lineage in Western countries, primary colorectal T-cell lymphomas are not uncommon in the East. The aim of this study was to review the clinical characteristics and treatment outcomes of primary colorectal lymphomas, with special emphasis on the differences between T-cell and B-cell lymphomas. Ninety-five cases of primary colorectal lymphomas that satisfied Dawson's criteria were identified from the clinical databases of 13 university hospitals in Korea. The mean age at the time of presentation was 51.1 years and the male:female ratio was 64:31. The clinical information, including endoscopic and histological characteristics, was retrospectively analyzed. Of the primary colorectal lymphomas, 78 cases (82.1%) were of B-lineage and 17 cases (17.9%) were of T-cell lineage. Patients with T-cell lymphomas presented at a younger age than patients with B-cell lymphomas (42.8 vs 52.9 years, respectively; P = 0.016). The most common presenting symptom was abdominal pain (87.1%) for B-cell lymphomas, whereas hematochezia or night fever was more common for T-cell lymphomas (52.9% and 35.3%, respectively). The most common endoscopic type was fungating mass (54.0%) for B-cell lymphomas and ulcerative/ulcero-infiltrative lesions (80.0%) for T-cell lymphomas. Intussusception was more common in B-cell lymphomas than in T-cell lymphomas (30.8% vs 5.9%, respectively; P = 0.035), but perforation was more common in T-cell lymphomas than in B-cell lymphomas (23.5% vs 3.8%, respectively; P = 0.005). The prognosis was significantly worse for T-cell lymphomas than for B-cell lymphomas (P = 0.002). Primary colorectal T-cell lymphomas are characterized by multifocal ulcerative lesions in relatively young patients, a high rate of hematochezia, fever, or perforation, and a poor prognosis even for cases of localized disease.

Adolescent↗

PubMed2005

Study of flow characteristics in a secondary clarifier by numerical simulation and radioisotope tracer technique.

Numerical simulation in a 2-D rectangular coordinate and experimental study have been performed to figure out the flow characteristics and concentration distribution of a large-scale rectangular final clarifier in wastewater treatment facility located in Busan, S. Korea. The purpose of numerical calculation is to verify the experimentally measured data by radioisotope tracer technique and further to understand the important physical feature occurring in a large-scale clarifier, in many cases which is not sufficient by the aid of limited number of experimental data. To this end, a comprehensive computer program is basically made by SIMPLE algorithm by Patankar with the special emphasis on the parametric evaluation of the various phenomenological models. Calculation results are successfully evaluated against experimental data obtained by the method of radioisotope tracer. Detailed comparison is made on the calculated residence time distribution (RTD) curves with measurement inside the clarifier as well as the exhaust. Further the calculation results predict well the well-known characteristics of clarifier flow such as the waterfall phenomenon at the front end of the clarifier, the bottom density current in the settling zone and the upward flow in the withdrawal zone. Thus it is believed that the flow calculation program and the data incorporation technique of radioisotope measurement employed in this study show the high possibility as a complementary tool of experiment in this area.

Journal Article↗

PubMed2005

Intussusception after gastric surgery.

Intussusception following gastric surgery is a rare postoperative complication. It may develop in clinical situations following gastroenterostomy, Billroth II gastric surgery with or without Braun anastomosis, or Roux-en-Y gastrojejunostomy. The patients may present with either an acute surgical emergency or with a chronic, relapsing form. The mortality may be up to 50 % in these cases if not treated appropriately, but little is known about the mechanism underlying the condition. Early diagnosis with a high index of suspicion and prompt treatment of the acute form are therefore important. Surgical reduction with laparotomy is mandatory, although definitive corrective and preventative measures have not yet been established.

Adult↗

PubMed2005

Cerebral fat embolism: diffusion-weighted magnetic resonance imaging findings.

PURPOSE: To demonstrate the diffusion-weighted (DWI) magnetic resonance imaging (MRI) findings, and the follow-up MRI findings, of cerebral fat embolism in the acute stage. MATERIAL AND METHODS: The initial DWI and clinical findings of six patients with cerebral fat embolism were retrospectively evaluated. The finding of DWI with a b-value of 1000 s/mm2 (b=1000) was compared with that of DWI with a b-value of 0 s/mm2 (b=0). In three patients who underwent follow-up MRI, the interval change of the lesion on T2-weighted images was investigated. RESULTS: The characteristic DWI finding of cerebral fat embolism in the acute stage was multiple, hyperintense, dot-like lesions disseminated in the brain. These lesions were distributed dominantly in the bilateral border-zone areas. Some lesions had an ancillary location including the cortex, deep white matter, basal ganglia, and cerebellum. The lesions were more intense and numerous in DWI (b=1000) than in DWI (b=0). The findings on the follow-up T2-weighted images were multiple confluent hyperintense lesions in the white matter with progression since the initial MRI. CONCLUSION: DWI could be a sensitive tool for detecting cerebral fat embolism in the acute phase. It is recommended that DWI be included in the initial evaluation of cerebral fat embolism with MRI.

Adult↗

PubMed2005

What the Aspergillus genomes have told us.

The sequencing and annotation of the genomes of the first strains of Aspergillus nidulans, Aspergillus oryzae, and Aspergillus fumigatus will be seen in retrospect as a transformational event in Aspergillus biology. With this event the entire genetic composition of A. nidulans, the sexual experimental model organism of the genus Aspergillus, A. oryzae, the food biotechnology organism which is the product of centuries of cultivation, and A. fumigatus, the most common causative agent of invasive aspergillosis is now revealed to the extent that we are at present able to understand. Each genome exhibits a large set of genes common to the three as well as a much smaller set of genes unique to each. Moreover, these sequences serve as resources providing the major tool to expanding our understanding of the biology of each. Transcription profiling of A. fumigatus at high temperatures and comparative genomic hybridization between A. fumigatus and a closely related Aspergillus species provides microarray based examples of the beginning of functional analysis of the genomes of these organisms going forward from the genome sequence.

Aspergillosis↗

PubMed2005

An aggressive form of familial amyloid polyneuropathy caused by a Glu54Gly mutation in the transthyretin gene.

We report a patient with familial amyloid polyneuropathy. Gene analysis revealed a heterozygous Glu54Gly substitution (A-to-G change) in the transthyretin gene. This is the first case of a Glu54Gly substitution that was devoid of a Gly6Ser substitution. Compared with the previously reported case with compound heterozygotes of Glu54Gly and Gly6Ser, the age of onset in our case is much younger and another characteristic findings were the amyloid vasculopathy and the multiple organ involvement. A Glu54Gly mutation is amyloidogenic by itself and a Gly6Ser mutation may offer some protection from the Glu54Gly mutant.

Amyloid Neuropathies, Familial↗

PubMed2005

Total knee arthroplasty in stiff knees after previous infection.

Between July 1986 and August 1996, we performed 32 total knee arthroplasties (TKA) on 32 patients with partially or completely ankylosed knees secondary to infection. Their mean age at surgery was 40 years (20 to 63) and the mean follow-up was ten years (5 to 13). The mean post-operative range of movement was 75.3 degrees (30 to 115) in those with complete and 98.7 degrees (60 to 130) in those with partial ankylosis. The mean Hospital for Special Surgery knee score increased from 57 to 86 points post-operatively. There were complications in four knees (12.5%), which included superficial infection (one), deep infection (one), supracondylar femoral fracture (one) and transient palsy of the common peroneal nerve (one). Although TKA in the ankylosed knee is technically demanding and has a considerable rate of complications, reasonable restoration of function can be obtained by careful selection of patients, meticulous surgical technique, and aggressive rehabilitation.

Adult↗

PubMed2005

Application of membrane bioreactor system with full scale plant on livestock wastewater.

A full-scale plant of an MBR system treating livestock wastewater has shown impressive results. The Cheorwon County Environmental Authorities adopted the MBR process with UF membrane for retrofitting the old plant, which removes organic matter, nitrogen and phosphorus at a high level. According to 6 months operation data, BOD and SS removal were about 99.9% and COD(Mn), TN and TP removal were 92.0%, 98.3% and 82.7%, respectively. It is considered that the temperature at the bioreactor has to be controlled to be below 40 degrees C so as to ensure sufficient nitrification. It appeared that the MBR system is competitive with other conventional technologies for treatment of livestock wastewater such as piggery waste.

Animals↗

PubMed2005

A pilot study on accelerated sludge degradation by a high-concentration membrane bioreactor coupled with sludge pretreatment.

A new sludge treatment process combining a high MLSS membrane bioreactor with sludge pretreatment techniques was studied in pilot-scale experiments. The membrane bioreactor (MBR) was adopted for high efficiency aerobic digestion. The combination of alkaline-ozone treatment of the mixed liquor in the MBR reactor accelerated the biodegradation process by enhancing biodegradability of the sludge. The hydraulic retention time (HRT) of the reactor was set as 3.1 days and the DO level was 1 mg/L on average. After 5 months of operation, the accumulative total solids reduction was more than 70%. Removal efficiency of volatile solids and non-volatile solids were 76% and 54%, respectively. It was found that a considerable portion of the non-volatile solids was dissolved into ions and then flushed out with the effluent. Also, about 41% and 28% of T-N and T-P in the raw sludge were removed although no biological nutrient removal process was adopted. The experiment was run smoothly without significant membrane fouling, even at the relatively high levels of MLSS concentration (11,000-25,000 mg/L). It is concluded that the newly proposed process can significantly increase the sludge reduction efficiency with much shorter retention times.

Biodegradation, Environmental↗

PubMed2005

Improvement of the thickening and dewatering characteristics of activated sludge by electroflotation (EF).

The performances of electroflotation (EF) on the thickening of activated sludge were investigated using laboratory scale batch flotation reactors. Four activated sludges including bulking sludges were tested. After 30 minutes of EF operation, 57-84% of sludge volume reduction could be achieved by EF, while only about 1.5-14% could be obtained by gravity thickening for the same period. After thickening the effluent water quality in terms of TCOD, SS, and turbidity was improved by EF operation for all sludge samples. In addition, the EF thickened sludge showed much better dewaterability both in SRF and cake solid content. It is induced that the air bubbles entrapped in the thickened sludge play a key role in the observed dewaterbility improvement.

Electrochemistry↗

PubMed2004

A new selection method for pepper transformation: callus-mediated shoot formation.

We used two genes, TMV-CP and PPI1 (pepper-PMMV interaction 1 transcription factor), to transform commercially important chili pepper (Capsicum annuum) inbred lines (P915, P409) by means of Agrobacterium co-culture. Eighteen independently transformed T0 plants were obtained. The most critical point in the pepper transformation protocol was the selection of shoots growing on calli--referred to as callus-mediated shoot formation (indirect shooting)--because shoots not grown from the callus (direct shooting from the wounded surface) developed into non-transformants. Selection of the correct right callus type also proved to be an important requirement for obtaining transformed peppers. Six different types of callus developed during the selection process. Shoots regenerated from two of these types, while one type regenerated significantly more shoots than the other types, suggesting that the capacity for shoot formation is callus type-specific. Although the transformation rate was low, transformation via callus-mediated shoot formation proved to be reproducible and was confirmed by Southern and Northern blot analyses. Based on the experimental data, we have succeeded in developing a new protocol for the selection and transformation of pepper and expect that it will be used in the future for pepper transformation.

Capsicum↗

PubMed2004

Expression of the hepatitis B surface S and preS2 antigens in tubers of Solanum tuberosum.

In an attempt to develop an edible vaccine, we transformed a recombinant hepatitis B virus (HBV) gene encoding the middle protein of HBV that contains the surface S and preS2 antigen into potato by Agrobacterium-mediated transformation. The HBV gene was under control of either the CaMV 35S promoter, the double 35S promoter with the AlMV 5' non-translated leader sequence, or the tuber-specific patatin promoter. HBV mRNA levels were higher with the 35S promoter than with the double 35S and patatin promoters; however, the levels of the S and preS2 antigen in the transformed tubers were higher with the patatin promoter than with the CaMV 35S and double promoters. The levels of preS2 antigen produced are the highest reported to date. Transgenic potato tubers were fed to mice, and the mice showed an immune response against the HBV S antigen.

Animal Feed↗

PubMed2004

Influence of donor and recipient gender on early graft function after living donor kidney transplantation.

Long-term effects of donor and recipient gender on the outcome of living donor kidney transplantation have been examined but the impact on early graft function is less certain. In this study, we analyzed age, gender, body weight, height, body surface area (BSA), and lean body weight (LBW) of both donors and recipients. Preoperatively we collected 24-hour urine samples to measure creatinine excretion from donor and postoperatively we determined when the recipient serum creatinine (Scr) reached baseline levels. Variables included were ischemic times, kidney graft weight, duration of dialysis, cause of end-stage renal disease (ESRD), degree of HLA match, and mismatch, types of immunosuppression (cyclosporine or FK506, dual or triple), and episodes of acute rejection. The variables were analyzed by independent sample t tests and chi-square statistics using SPSS. Values of P < .05 were considered significant. Male patients of both donors and recipients were significantly taller and heavier (higher BSA and LBW) than female. Urinary 24-hour creatinine excretion was greater in male patients whether donors or recipients. There were no statistical differences in graft weight or creatinine clearance based on the gender of the donor or recipient. The creatinine of male donors or recipients was higher than that of females. The other variables were not significantly different. In conclusion, the effect of donor or recipient gender on early graft function depends on the metabolic demands, which are higher in male recipients.

Adult↗

PubMed2004

Genetic analysis of the LKB1/STK11 gene in hepatocellular carcinomas.

The tumour suppressor gene, LKB1/STK11, has been mapped to chromosome 19p13, a region showing frequent allelic loss in various human cancers, including hepatocellular carcinoma (HCC). Additionally, LKB1 physically associates with p53 and regulates p53-dependent apoptotic pathways. To investigate whether genetic alterations of LKB1 could be involved in the tumorigenesis of HCC, we analysed the genetic alterations of the LKB1 and p53 genes in seven dysplastic nodules and 80 HCCs. We found one LKB1 missense mutation, CCG-->CTG (Pro-->Leu) at codon 281 within the kinase domain. We also found allelic loss in six of 27 (22%) informative HCC cases and all of them were HBV-positive cases. In addition, we detected seven missense, one nonsense and one silent mutations (nine of 80, 11%) of p53 in HCCs only. These results suggest that genetic alterations of the LKB1 or p53 genes may play an important role in tumour development or progression of a sub-set of HCCs, and may also provide alternative mechanisms to protect the HCC cell from p53-dependent apoptosis.

AMP-Activated Protein Kinase Kinases↗