Vertical growth of core-shell III-V nanowires for solar cells application.

High density (In)GaAs/GaAs/AIGaAs nanowires (NWs) consisting of n-type core and p-type shell have been vertically grown on (111) GaAs substrate using metal organic chemical vapor deposition (MOCVD) and fabricated into solar cells. Au colloidal nanoparticles (NPs) are employed as a catalyst. High density nanowires were obtained by uniform distribution of Au NPs. Fe-SEM, TEM and HRTEM images show that the morphology of shell is sensitive to p-doping concentration. Increase in the density of p-doping precursor results in "kinking" of NPs and rough shell surface. The origin of kinking has been explained by the GaAs twin phases due to Zn segregation on the surface of shell. It has been observed that the morphology of NPs can be controlled through optimizing various source purge technique of DEZn and deposition temperature. Electrical properties of core-shell doped NWs are carried out using I-V characterization. The core-shell NWs show characteristics of p-n junction as revealed by I-V studies.

First Report of Clover yellow vein virus on Glycine max in Korea.

Glycine max (Soybean) is the most important edible crop in Korea. In Korea, eight viruses have been reported to infect soybean, including Alfalfa mosaic virus (AMV), Cowpea mosaic virus (CPMV), Cucumber mosaic virus (CMV), Soybean dwarf virus (SbDV), Soybean mosaic virus (SMV), Soybean yellow common mosaic virus (SYCMV), Soybean yellow mottle virus (SYMMV), and Peanut stunt virus (PSV) (1). In 2012, Glycine max were observed in Daegu, South Korea, with mosaic and mottling symptoms on leaves. Samples with virus-like symptoms (n = 151) were collected from Daegu including legume genetic resource field. Virus particles were filamentous rod shaped, average length 760 nm, and were analyzed by RT-PCR using specific primers for several Potyviruses and previously reported viruses infecting soybean. Only two samples showing mosaic and mottling symptoms were identified as Clover yellow vein virus (ClYVV) based on RT-PCR using primers specific for ClYVV (5'-GTTGGCTTGGTTGACACTGA-3' and 5'-CTTCGATCATGGATGCACA-3'). The sequences of amplified fragments were 97 to 98% similar with ClYVV. ClYVV is a distinct species in the genus Potyvirus and family Potyviridae. ClYVV is transmitted by several species of aphids and by mechanical inoculation (2). ClYVV was first reported on Gentiana scabra, and the disease has never been reported in soybean fields in Korea. The biological properties and full genome sequence of the selected ClYVV isolate of apparent virus symptoms between two samples were analyzed. The ClYVV isolate was inoculated to local lesion plants, re-isolated from local lesions three times, and propagated in Nicotiana benthamiana, and then named ClYVV-Gm. The ClYVV-Gm induced local lesions on inoculated leaves of N. tabacum cv. Xanthi-nc, Tetragonia expansa, and systemic symptoms on upper leaves of Chenopodium amaranticolor, C. quinoa, and N. clevelandii. The ClYVV-Gm caused mosaic and mottling symptoms on Glycine max cv. Kwangan and Phaseolus vulgaris. The genome of ClYVV-Gm was determined to be 9,584 nucleotides in length (GenBank Accession No. KF975894), and it shared 83% to 97% nucleotide identity with the sequences of 27 previously reported ClYVV isolates including Vicia fava and Pisum sativum. Despite low occurrence of ClYVV in Glycine max, ClYVV has a broad host range including tobacco, weed species, and soybean, which can lead to spreading of the virus. Our results indicate that emergence of ClYVV could become a problem to Leguminosae in Korea. To our knowledge, this is the first biological and molecular report of ClYVV infecting Glycine max in Korea. References: (1) Y. H. Lee et al. Korea Soybean Digest 29:7, 2012. (2) T. Sasaya et al. Phytopathology 87:1014, 1997.

A novel COL7A1 mutation in a Korean patient with Hallopeau-Siemens recessive dystrophic epidermolysis bullosa.

Dystrophic epidermolysis bullosa (DEB) is an inherited skin fragility disorder that presents various clinical manifestations. DEB is characterized by separation of sublamina densa tissue and abnormalities in the anchoring fibrils that result from mutations in COL7A1 and subsequent defects in type VII collagen. A 16-month-old boy was diagnosed with Hallopeau-Siemens recessive DEB on the basis of typical skin lesions composed of multiple blisters with moderately healed erosions, scarring on trauma-exposed body sites, including hands and feet, pseudosyndactyly and flexion contractures of the toes, and severely dystrophic nails on the right hand. Genomic DNA from the patient and parents were subjected to direct sequencing for the COL7A1 gene. Two heterozygous mutations were detected in the affected child; one novel mutation designated c.4232delC in exon 38 and a single-base substitution (c.6573+1G>C) in intron 81. Deletion of a single cytosine at codon 1411 within exon 38 had produced a frameshift mutation that created a stop codon at codon 1427 (p.Pro1411Leufs*17). This intronic base substitution had led to aberrant splicing and a premature termination codon. This is a novel mutation of COL7A1 associated with DEB in a Korean patient, adding to the range of COL7A1 mutations related to DEB.

Comparison of lower extremity motor score parameters for patients with motor incomplete spinal cord injury using gait parameters.

STUDY DESIGN: Retrospective investigation using gait analysis and medical records. OBJECTIVE: To evaluate the relationship between ambulatory function improvement and an increase in lower-limb motor scores in persons with motor incomplete spinal cord injury (SCI) and to compare the efficiency of lower extremity motor score (LEMS) and ambulatory motor index (AMI) in representation of ambulatory function improvement using gait analysis. SETTING: SCI Unit, Yonsei Rehabilitation Hospital, Seoul, Korea. METHODS: The gait analysis from 43 patients with SCI (paraplegic, n=22, tetraplegic n=21) were reviewed. The gait analysis data were obtained with Vicon 370 system. The LEMS and AMI were assessed before the gait analysis and the influence of an increase in lower-limb motor scores were investigated with linear parameters of gait analysis. RESULTS: For group including both tetraplegic and paraplegic patients, both AMI and LEMS were statistically correlated with gait speed, step length and negative correlation with double-limb support. However, only LEMS was correlated with cadence. For the paraplegic group, with AMI and LEMS, there were correlation with gait speed, step length and right single-limb support and negative correlation with right double-limb support. However, only LEMS was correlated with left cadence and negative correlation with double-limb support. For the tetraplegic group, only left cadence was statistically correlated with AMI. CONCLUSION: Both AMI and LEMS were useful in terms of providing information for capability of ambulatory function for the paraplegic group. However, for the tetraplegic group, both AMI and LEMS do not provide sufficient information for ambulatory function of the incomplete SCI patients.

Dysphagia in cervical spinal cord injury.

STUDY DESIGN: Retrospective chart review of cervical spinal cord injury patients, who underwent videofluoroscopic swallowing study (VFSS). OBJECTIVES: To evaluate the swallowing function of cervical spinal cord injury patients, analyze the features of dysphagia and investigate their association with the clinical symptoms and signs. SETTING: Spinal Cord Injury Unit, Yonsei Rehabilitation Hospital, Seoul, Korea. METHODS: Retrospective study (1 May 2001-31 May 2008) on inpatients with tetraplegia. All enrolled patients underwent VFSS, and their results were correlated with clinical data including symptoms and signs indicative of dysphagia. RESULTS: A total of 121 cervical spinal cord injury patients (106 male and 16 female patients) were included in this study. Ten patients showed evidence of aspiration on VFSS. Statistical correlation to aspiration was found with age, presence of tracheostomy, and symptoms and signs indicating dysphagia. However, out of the 10 patients with evident aspiration, 2 patients did not show any symptoms or signs indicating aspiration. CONCLUSION: Because of the possibility of silent aspiration, we recommend that physicians treating patients with cervical spinal cord injury should always take the possibility of dysphagia and silent aspiration into consideration, especially in case of previous manifestation of pneumonia, presence of tracheostomy, or presence of signs and symptoms indicating dysphagia.

Identification of differentially expressed genes using annealing control primer-based GeneFishing in human squamous cell cervical carcinoma.

AIMS: To compare different gene expression patterns between squamous cell cervical carcinoma (SCC) and normal cervical tissue in Korean women and to identify those genes that are specifically or predominantly expressed in SCC by employing annealing control primer (ACP)-based GeneFishing polymerase chain reaction (PCR). MATERIALS AND METHODS: Cervical cancer specimens were obtained from patients enrolled at the Department of Obstetrics and Gynecology, Kang Nam St. Mary's Hospital, Catholic University of Korea. We used a common reference that was mixed with an equal amount of RNA extracted from patients without cervical cancer. The profiles of expressed genes were compared between the SCC and normal cervix identified using GeneFishing differentially expressed gene kits, screened by a BLAST search, and confirmed by semi-quantitative reverse transcription-PCR (RT-PCR). RESULTS: Almost 100 differentially expressed genes were identified in the control and SCC samples. Using 60 arbitrary ACPs, 50 differentially expressed genes were identified, and 30 up-regulated and 20 down-regulated expressed genes were sequenced. Among 50 clones selected by ACP-based GeneFishing PCR, six genes with different expression patterns were determined and confirmed by semi-quantitative RT-PCR. The functional roles of two up-regulated genes, fibrillarin and calgranulin A, and one down-regulated gene, clusterin, were previously identified. However, the functional roles of two up-regulated genes and one down-regulated gene were not identified. CONCLUSION: We identified distinctive gene expression profiles in Korean women with SCC using ACP-based GeneFishing PCR.

Predictors of idiopathic thrombocytopenic purpura in pregnant women presenting with thrombocytopenia.

OBJECTIVE: Idiopathic thrombocytopenic purpura (ITP) and gestational thrombocytopenia (GT) are common causes of thrombocytopenia during pregnancy. Despite an ever-increasing experience with these disorders, differentiation between the two entities still remains a diagnostic challenge. The current study attempted to identify the antenatal predictors of ITP for pregnant women. METHODS: Between January 1999 and June 2005, a total of 58 pregnant women with a presumptive diagnosis of either ITP or GT were recruited for the study. All of them had platelet counts of less than 100 x 10(9)/L. The predictors of ITP were evaluated by comparison between the two disorders. RESULTS: The detection of thrombocytopenia prior to 28 weeks of gestation and platelet counts <50 x 10(9)/L at its diagnosis remained independently predictive of ITP (P<0.001 and P=0.004, respectively). The combined analysis of these two factors provided a 96.0% sensitivity and a specificity of 75.8%. CONCLUSION: The onset time of thrombocytopenia and platelet count at its presentation remain the strongest predictors of ITP for pregnant women. The combination model using these factors may be useful for the early prediction of ITP.

Supportive management of pregnancy-associated aplastic anemia.

OBJECTIVE: To examine maternal and fetal outcomes of pregnancy-associated aplastic anemia treated with supportive care. METHODS: From January 1995 to December 2004, 14 women newly diagnosed as having pregnancy-associated aplastic anemia were recruited for the study. RESULTS: Diagnosis was made during the second or third trimester for 11 (78%) of the 14 patients, and 3 of the 8 severe cases of aplastic anemia were diagnosed at initial presentation. All patients had conservative management with transfusions but no specific immunologic or hormonal therapy during pregnancy. Of the 12 women eligible for follow-up, 1 achieved complete remission and 8 achieved partial remission after delivery. The pregnancies progressed uneventfully in most cases. CONCLUSIONS: This study demonstrated favorable maternal and neonatal outcomes with transfusion support alone for pregnancy-associated aplastic anemia.

Involvement of phospholipase D in oxidative stress-induced necrosis of vascular smooth muscle cells.

Phospholipase D (PLD) has been associated with necrosis. However, it is not clear whether PLD plays a causative role in this cellular process. We investigated the role of PLD in oxidative stress-induced necrosis of vascular smooth muscle cells (VSMCs). Pervanadate (hydrogen peroxide plus orthovanadate) but not hydrogen peroxide alone activated PLD in a dose- and time-dependent manner. Exposure of VSMCs to pervanadate resulted in necrosis. Pretreatment with butan-1-ol, a PLD inhibitor, attenuated both pervanadate-induced necrosis and increase of intracellular Ca(2+). Removal of extracellular Ca(2+) inhibited pervanadate-induced necrosis by 50%. These results suggest that PLD activation mediates pervanadate-induced necrosis of VSMCs, which is at least partly due to Ca(2+) toxicity.

Prospective study of microvascular decompression in hemifacial spasm.

OBJECTIVES: Although, in most cases, the symptoms of hemifacial spasm (HFS) disappear immediately after microvascular decompression (MVD), in some cases, they disappear more gradually. The objectives of this study were to observe the time course and the rate of the delayed resolution and to attempt to explain the phenomenon through long-term follow-up of HFS after MVD. METHODS: Two hundred and sixty-one patients with HFS who underwent MVD were followed up to observe clinical changes. Two hundred and twenty-six of the 261 patients were followed up for a duration of 6 months to 2 years, from 1985 to 1995. RESULTS: After the 1st week of the surgery, 61.1% of the patients were rated as having achieved excellent results. When the patients were followed up for more than 6 months, however, the rate improved to 82.7%. The clinical results of HFS after MVD improved significantly with time (P < 0.05). Delayed resolution of HFS was observed in 37.4% of the patients who experienced complete resolution; it was the most important factor for clinical improvement during the follow-up period. Abnormal muscle response immediately after MVD in the operating room was also positively correlated with resolution during the follow-up period (correlation coefficient = 0.3099, P < 0.05). CONCLUSIONS: In conclusion, the clinical picture of HFS after MVD improves with time, and abnormal muscle response can be used as a prognostic indicator for the resolution of HFS during the follow-up period.

Intraoperative monitoring of microvascular decompression in hemifacial spasm.

The significance of intraoperative electrophysiologic monitoring during microvascular decompression was evaluated prospectively in 261 patients with the hemifacial spasm from 1985 to 1995. The patients were divided into a monitored group and a non-monitored group. Identification of the offending vessels was facilitated by the monitoring during the surgical procedure and the complication rate of the monitored group was significantly lower than that of the non-monitored group (p < 0.05). In addition, the abnormal muscle response continued to improve during the follow-up period, thus the electrophysiological status of the hemifacial spasm after the microvascular decompression improved significantly with time (p < 0.05). In conclusion, intraoperative monitoring is useful for identifying the exact offender among multiple vessels, and lowering the complication rate of the microvascular decompression for the hemifacial spasm.

Prosthetic ambulation in a paraplegic patient with a transfemoral amputation and radial nerve palsy.

Great importance and caution should be placed on prosthetic fitting for a paraplegic patient with an anesthetic residual limb if functional ambulation is to be achieved. The combination of paraplegia with a transfemoral amputation and radial nerve palsy is a complex injury that makes the rehabilitation process difficult. This article describes a case of L2 paraplegia with a transfemoral amputation and radial nerve palsy on the right side. Following the rehabilitation course, the patient independently walked using a walker at indoor level with a transfemoral prosthesis with ischial containment socket, polycentric knee assembly, endoskeletal shank and multiaxis foot assembly and a knee ankle foot orthosis on the sound side. The difficulties of fitting a functional prosthesis to an insensate limb and the rehabilitation stages leading to functional ambulation are reviewed.

Efficacy of hydrocolloid occlusive dressing technique in decubitus ulcer treatment: a comparative study.

The efficacy of hydrocolloid occlusive dressing technique was compared with that of the conventional wet-to-dry gauze dressing technique in decubitus ulcer of stage I and II. Forty-four patients were randomly divided into two treatment groups and each received treatment according to the two different protocols. As a result, 80.8% of the hydrocolloid occlusive dressing group (group 1) and 77.8% of the conventional wet-to-dry gauze dressing group (group 2) healed completely with no statistically significant difference between the two groups. However, the time required for complete healing was shorter in group 1 with 18.9 days compared to 24.3 days in group 2. Ulcer healing speed was also slightly faster in group 1 with 9.1 mm2/day compared to 7.9 mm2/day for group 2. Average treatment time spent by a medical staff member was significantly shorter in group 1 with 20.4 minutes/day compared to 2017 minutes/day in group 2. The hospital cost of the ulcer treatment was higher in group 2 compared to group 1 even without taking into consideration the medical personnel's labor cost. These results indicate that the hydrocolloid occlusive dressing technique offers less time consuming and less expensive method of treatment compared to the conventional technique in stage I and II decubitus ulcers.

Prospective evaluation of perinatal risk factors for cerebral palsy and delayed development in high risk infants.

Prematurity, intrauterine infection and perinatal brain injury have been reported to be significant risk factors of cerebral palsy (CP). We examined the perinatal predictors of cerebral palsy and delayed development (DD) in 184 high risk infants. Thirty-five infants were diagnosed as cerebral palsy and delayed development at 12 months corrected age. Antenatal, intrapartum, and neonatal factors were prospectively evaluated in 2 groups of high risk infants compared with controls; Group A (n = 79), infants weighing less than 2,000 g; Group B (n = 43), infants weighing 2,000 g or more. In univariate analysis, there were no significant antenatal and intrapartum factors associated with cerebral palsy and delayed development in either group. We found that significant postnatal risk factors of CP in group A included sepsis (p = 0.008), BPD (bronchopulmonary dysplasia) (p = 0.028), IVH (intraventricular hemorrhage) (p = 0.042), ventriculomegaly (VM) (p = 0.001) and a longer duration of mechanical ventilation (p = 0.001); while in group B, sepsis (p = 0.047) and neonatal seizure (p = 0.027) were significant risk factors. In multivariate analysis, sepsis in group B was a moderate risk factor of CP (OR (odds ratio) 1.47; 95% CI (confidence interval) 1.02-2.13). In conclusion, neonatal sepsis may contribute to the development of cerebral palsy and delayed development. We suggest that high risk infants who have sepsis should be carefully followed for cerebral palsy and delayed development. The prevention of cerebral palsy may be feasible by decreasing neonatal risk factors such as sepsis during the neonatal period.

Elective vs. conservative management of ovarian tumors in pregnancy.

OBJECTIVES: To determine optimal management of the ovarian tumors in pregnancy. METHODS: This study included 89 cases of the ovarian tumor in pregnancy that required surgery at Holy Family hospital of the Catholic University from January, 1990 to December, 2001. Among 89 cases, 36 and 53 were emergency and elective surgery, respectively. Student's t-test and the chi(2)-test were used for statistical analysis and a P-value of <0.05 was considered statistically significant. RESULTS: The most common size of torsion of ovarian tumors during pregnancy was 6-10 cm and the incidence was the most frequent during the first trimester of pregnancy. The incidence of preterm delivery (<37 weeks) was higher in emergency surgery, but there was no difference in the gestational age at delivery, also no difference in the birth weight or the method of delivery. CONCLUSIONS: Although surgery for ovarian tumors in pregnancy is delayed until the onset of symptoms, adverse pregnancy outcome is not worsened when compared with that after elective surgery. We propose that conservative management would be used in optimal management of pregnant women with ovarian tumors.

Expression of insulin-like growth factor-II and insulin-like growth factor binding protein-1 in the placental basal plate from pre-eclamptic pregnancies.

OBJECTIVES: To determine whether expressions of insulin-like growth factor-II (IGF-II) and insulin-like growth factor binding protein-1 (IGFBP-1) are altered in pre-eclamptic placenta and to elucidate the possible relationship between their expressions and a mechanism for inadequate trophoblast invasion in pre-eclampsia. METHODS: Placental tissues were obtained at cesarean delivery from five normotensive, nine mild pre-eclamptic and five severe pre-eclamptic women at 33-39 completed weeks of gestation. After total ribonucleic acid was extracted, reverse transcriptase-polymerase chain reaction was performed to determine IGF-II and IGFBP-1 mRNA expression. Product bands were quantitated by scanning densitometry and results were expressed as ratio of cytokines/beta-actin. Western blot analysis was also done to determine IGF-II and IGFBP-1 protein expression. Statistical analysis was determined by Kruskal-Wallis analysis of variance with the Scheffe multiple post-hoc test. RESULTS: The IGF-II mRNA levels of mild and severe pre-eclamptic placenta were significantly lower than that of uncomplicated placenta (P<0.005, P<0.001, respectively), with the level of severe pre-eclamptic placenta being significantly lower than that of mild pre-eclamptic placenta (P<0.05). As for the IGF-II protein expression, a significant decrease was found among the three groups (P<0.001), correlating with the IGF-II mRNA results. However, the mean IGFBP-1 mRNA levels of mild and severe pre-eclamptic placenta were significantly higher than that of uncomplicated placenta (P<0.05, P<0.005, respectively), with the level of severe pre-eclamptic placenta being significantly raised compared with that of mild pre-eclamptic placenta (P<0.05). Finally, a significant increase of IGFBP-1 protein expression was noted among the three groups (P<0.001), correlating with the IGFBP-1 mRNA results. CONCLUSIONS: This study suggests that IGF-II and IGFBP-1 might be associated with the impaired trophoblastic invasion that may lead to pathogenesis of pre-eclampsia.

Spectral analysis of fetal heart rate variability as a predictor of intrapartum fetal distress.

OBJECTIVE: To evaluate the usefulness of power spectral analysis on fetal heart rate variability as a new diagnostic method of fetal distress. STUDY DESIGN: Among 76 pregnant women who underwent computerized electronic fetal monitoring and cord blood gas analysis, we divided them into three groups: normal fetus group (36); presumed distress group (26); and acidemic distress group (14). In order to perform linear analysis on the raw data of the fetal heart rate, after resampling, we performed Fourier transformation and investigated power distributions among very low frequency (VLF), low frequency (LF), high frequency (HF) bands, and autonomic balance (LF/HF). RESULTS: The results of the spectral analysis showed that in normal fetus group, the difference in the distribution of power spectrums of VLF, LF and HF was significantly higher than in presumed distress group and acidemic distress group. In fetal distress, the LF and VLF value (< or = 0.0023, > or = 0.0437) were good predictors (sensitivity 97.5%, 75.0% and specificity 86.1%, 94.4%). The LF value (< or = 0.0013) was a good predictor in fetal acidemia (sensitivity 97.5% and specificity 86.1%). CONCLUSIONS: A computerized spectral analysis of fetal heart rate variation is a good predictor of fetal distress, which is made automatically and objectively.

Statistical analysis of amputations and trends in Korea.

Epidemiological research on amputees is being continued extensively world wide, but there are different epidemiologic reports from country to country. This study undertakes an epidemiologic report of the medical records of amputees in Korea which has developed very rapidly, when compared with other countries. This study included 4258 amputees who either had an amputation and/or received prosthetic training at Yonsei University College of Medicine, Severance Hospital from January 1970 to June 1994. The most common cause of amputation was trauma (66.7%), and the second most common cause was peripheral vascular disease. While amputations due to infection or trauma were the most common in the 1950's, amputations due to peripheral vascular disease have gradually increased until they now make up 23.5% of all amputations in the 1990's. Lower limb amputation, more common than upper limb amputation, accounted for 68.7% of all amputation. Multiple amputation accounted for 9.3% of all amputations, and the occurrence rate of multiple amputation was relatively higher in cases of burn injuries, train accidents, frostbite, and Buerger's disease than in cases brought about by other causes. The various amputation causes change according to the circumstances of the times, as can be seen in this study.

Rehabilitation of a triple amputee including a hip disarticulation.

A multiple amputee more severe than a triple amputee is uncommon. There have been no reports on the rehabilitation outcome of a triple amputee, including hip disarticulation and transtibial amputation. The authors report the rehabilitation of a patient with left hip disarticulation, right trans-tibial amputation, and left trans-humeral amputation due to a train accident. He has successfully completed the rehabilitation programme and has become independent in prosthetic ambulation, activities of daily living, and driving.