• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.285-292
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• 2011

In plants, heteroblasty reflects the morphological adaptation during leaf development according to the external environmental condition and affects the final shape and size of organ. Among parameters displaying heteroblasty, leaf index is an important and typical one to represent the shape and size of simple leaves. Leaf index factor is eventually determined by cell proliferation and cell expansion in leaf blades. Although several regulators and their mechanisms controlling the cell division and cell expansion in leaf development have been studied, it does not fully provide a blueprint of organ formation and morphogenesis during environmental changes. To investigate genes and their mechanisms controlling leaf index during leaf development, we carried out molecular-genetic and physiological experiments using an Arabidopsis mutant. In this study, we identified macrophylla (mac) which had enlarged leaves. In detail, the mac mutant showed alteration in leaf index and cell expansion in direction of width and length, resulting in not only modification of leaf shape but also disruption of heteroblasty. Molecular-genetic studies indicated that mac mutant had point mutation in ROTUDIFOLIA3 (ROT3) gene involved in brassinosteroid biosynthesis and was an allele of rot3-1 mutant. We named it mac/rot3-5 mutant. The expression of ROT3 gene was controlled by negative feedback inhibition by the treatment of brassinosteroid hormone, suggesting that ROT3 gene was involved in brassinosteroid biosynthesis. In dark condition, in addition, the expression of ROT3 gene was up-regulated and mac/rot3-5 mutant showed lower response, compare to wild type in petiole elongation. This study suggests that ROT3 gene has an important role in control of leaf index during leaf expansion process for proper environmental adaptation, such as shade avoidance syndrome, via the control of brassinosteroid biosynthesis.

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.171-182
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• 2018

Papaya (Carica papaya L.) is one of the crops widely planted in tropical and subtropical areas. The papaya fruit has low calories and are plentiful in vitamins A and C and in minerals. A major problem in papaya production is a plant disease caused by the papaya ringspot virus (PRSV). The first PRSV-resistant GM papaya expressing a PRSV coat protein gene was developed by USA scientists in 1992. The first commercial GM papaya cultivars derived from the event was approved by the US government in 1997. Development of transgenic papayas has been focused on vaccine production and limited agricultural traits, including insect and pathogen resistance, long shelf life, and aluminum and herbicide tolerance. Approximately 17 countries, including the USA and China, produced transgenic papayas and/or commercialized them, which provoked studies on biosafety assessment and development of GM-detection technologies. For the biosafety assessment of potential effects on human health, effects of long-term feeding to model animals have been studied in terms of toxicity and allergenicity. Studies on environmental safety assessment include influence on soil-microbial biodiversity and transfer to soil bacteria of GM selection markers. Many countries, such as Korea, the European Union, and Japan, that have strict regulations for GM crops have serious concerns about unintended introduction of GM cultivars and food commodities using unauthorized GM crops. Transgene- and/or GM event-specific molecular markers and technologies for genomics-based detection of unauthorized GM papaya have been developed and have resulted in the robust detection of GM papayas.

• Journal of Chest Surgery
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• v.34 no.9
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• pp.704-710
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• 2001

Background: Extracorporeal circulation using pump-oxygenator is an inevitable process to keep vital sign during cardiac arrest for open heart surgery. However, the diversion of blood through nonendothelialized channels appears to stimulate inflammatory response, and leukocyte activation may lead to cardiopulmonary edema. Our study evaluated the effect of leukocyte-induced cardiopulmonary edema using three different pump-oxygenator priming solutions; non-hemic crystalloid solution ; leukocyte-depleted homologous blood; non leukocyte-depleted homologous blood in priming solutions. Material and Method: Each different priming solution was used on five dogs, and the effect of leukocyte-induced cardiopulmonary edema during cardiopulmonary bypass(CPB) was evaluated. For each dog after 2 hours of exracorporeal circulation and another 4 hours of post-pump period, the dog was sacrificed and its heart and lung tissues were obtained for measuring Wet/Dry ratio. Arterial $O_2$partial pressure(PaO$_2$) and $CO_2$partial pressure(Pa$CO_2$) were checked. For the evaluation of ventilatory function, $CO_2$partial pressure difference between arterial blood (Pa$CO_2$) and exhaled air(Et$CO_2$) was measured. Result: 1. No significant difference was seen in arterial PaO$_2$and Pa$CO_2$among groups. 2. Ventilatory function evaluated by Pa$CO_2$and Et$CO_2$showed no significant difference between non-hemic and blood-mixed priming solution (P<0.05). 3. Cardiac and lung Wet/Dry ratios were remarkedly lower in the leukocyte-depleted group. There was no significant difference between the non-hemic and blood-mixed groups. Conclusion: Based upon this result, we concluded that the leukocyte depletion from homologous blood of CPB priming solution has a beneficial effect in reducing cardiopulmonary edema compared with non leukocyte-depleted or crystalloid priming solutions.

• Journal of Chest Surgery
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• v.32 no.4
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• pp.341-346
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• 1999

Background: Thirty children ranging from 3 to 15 years of age underwent cardiac valve replacement at Dongsan Medical Center from 1982 to 1997. Material and Method: There were 16 boys and 14 girls. The mean age was 12.1. The underlying pathological cause for valve replacement was congenital heart disease in 17 children and acquired heart disease in 13. The valve replaced was mitral in 15 children, aortic in 11, tricuspid in 3, and combined aortic and mitral in 1. Twenty-one mechanical and 10 tissue valves were placed: primary mechanical valve have been utilized since 1985. Eight of ten patients with tissue valves have had successful second valve replacements 4 to 11 years after the initial operation. Result: The operative mortality was 6.7%, but mortality was higher among patients less than 5 years of age and patients who had previous cardiac operations. Of the 28 operative survivors, 4 patients were lost to follow-up: the remaining patients were observed for a total of 2091 patient/months(mean 74.7 months, maximum 187 months). There was one late death from dilated cardiomyopathy after mitral valve replacement in 7 year-old patient with atrioventricular septal defect. After the operation, all patients with mechanical valves were placed on a strict anticoagulant regimen with Coumadin. The actuarial survival rate was 96% at the end of the follow-up. No instance of thromboembolism or major bleeding were observed in the survivors. Conclusion: These results indicate that valve replacement can be performed with low mortality in children, and with satisfactory long-term survival.

• Journal of Chest Surgery
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• v.32 no.4
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• pp.358-363
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• 1999

Background: Recently, many cardiac centers have been using aprotinin to reduce operative bleeding in cardiac operations using cardiopulmonary bypass. A variety of reports have confirmed the effectiveness of the drug in cardiac operations. In addition to the operations which could be considered to cause severe operative bleeding such as redo operation, long cardiopulmonary bypass operation and etc, the use of aprotinin is increasing in the field of primary cardiac operations. Varying doses of regimen have been introduced since the first report by Royston et al, and also various opinions on the effectiveness and safeness of the each regimen have been reported. We reviewed our own experience of the full dose aprotinin regimen(Hammersmith regimen) retrospectively. Material and Method: From October 1994 to February 1998, 40 cases of cardiac operative patients were randomized into two groups: aprotinin group(20 patients) which received a full dose aprotinin regimen and control group(20 patients) which did not receive aprotinin. To evaluate the degree of bleeding decrease, we analysed and compared the amount of postoperative 6 hours and 24 hours bleeding in the each group. To confirm the renal dysfunction, we measured the postoperative creatinine level. Result: In the amount of postoperative 6 hours bleeding, a statistically significant bleeding decrease was demonstrated in the aprotinin group compared to the control group(aprotinin group: 186${\pm}$40cc, control group:409${\pm}$69cc, P=0.010). Similar result was observed in the postoperative 24 hours(aprotinin group:317${\pm}$53cc, control group: 671${\pm}$133cc, P=0.024). Conclusion: We concluded that full dose regimen of aprotinin can remarkably reduce postoperative bleeding in cardiac operations without significant renal dysfunctions.

• Journal of Chest Surgery
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• v.35 no.5
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• pp.329-335
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• 2002

Background: The surgical technique for biventricular assist device(BVAD) implantation has mainly consisted of cannulation procedures. A median sternotomy has been the technique of choice as it gives a surgeon an excellent exposure of the heart. However, considering that most patients require a future sternotomy or already have a previous sternotomy, sternotomy-related complication remains a major concern in BVAD implantation. Based on this consideration as well as the clinical experiences of conventional heart surgery, the authors have hypothesized that the cardiac chambers for BVAD cannulation can be approached from the right side of the heart. The purpose of this studs to develop a novel surgical technique of right thoracotomy for BVAD implantation in an animals study. Material and Method: For last two years, 16 (11 calves, 3 canines, and 2 sheep) out of 30 experimental animals with AnyHeart implantation underwent a right thoracotomy. The device was used as an implantable BVAD in 14 animals, a wearable BVAD in 1, and an implantable LVAD in 1. The chest cavity was entered through the 4th intercostal space or the 5th periosteal bed. As for the BVAD use, a right inflow cannula was inserted into the right atrial free wall and a right outflow cannula was grafted onto the main pulmonary artery. A left inflow cannula was inserted into the interatrial groove and a left outflow cannula was grafted on the innominate artery of the ascending aorta. The connecting tubes were brought out through the thoracotomy wound and connected to the pump located in the subcutaneous pocket at the right flank. Result: Except for the 5 animals for a lilting test or during the early learning curve, all recovered smoothly from the procedures. The inflow drainage allowed the pump output 6.5 L/min at the maximum with 3-3.5 L/min in an average. Of the survivors, there noted no procedure-related mortality or morbidity. Necropsy findings demonstrated the well-positioned cannula tips in the each cardiac chamber

• Nuclear Medicine and Molecular Imaging
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• v.40 no.6
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• pp.316-321
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• 2006

Purpose: Differential diagnosis between arteriovenous (AVMs) aud non-arteriovenous malformations (nAVMs) is important in patients with congenital vascular malformations, because AVMs can cause hemodynamic alteration and require immediate treatment. We investigated whether transarterial lung perfusion scintigraphy (TLPS) was useful for the diagnosis and post-therapeutic evaluation of AVMs in extremities. Materials and Methods: Fifty-seven patients (M:F=26:31, $21{\pm}13$ yr, 9 upper and 48 lower extremities) suspected of congenital vascular malformations in extremities underwent TLPS using $^{99m}Tc-MAA$ before embolization/sclerotherapy. Dose-corrected shunt fraction (SF) was calculated from time-activity curve of the lung. Final diagnosis of AVMs was determined by angiography. in patients with AVMs, follow-up TLPS was done for post-therapeutic evaluation. Results: Sixteen patients (8 upper and 8 lower extremities) had AVMs, while the remaining 41 had nAVMs (1 upper and 40 lower extremities). The mean SF of AVMs on TLPS was significantly higher than that of nAVMs ($66.4{\pm}25.8%\;vs.\;2.8{\pm}4.3%$), p=0.003). The sensitivity, specificity, and accuracy of TLPS (cut-off of SF = 20.0%) in diagnosis of AVMs before treatment were 93.8% (15/16), 100% (41/41) and 98.2% (56/57), respectively. The follow-up TLPS and angiography for post-therapeutic evaluation showed concordant results in 13 of 16 patients (81.3%) with AVMs. The mean SF of TLPS was significantly decreased after embolization/sclerotherapy ($69.5{\pm}24.0%\;vs.\;41.0{\pm}34.7%$, p=0.01). Conclusion: TLPS provides hemodynamic information of AVMs in extremities semiquantitatively. Furthermore, the results of TLPS showed a high concordance rate with angiographic findings. Therefore, TLPS is useful for the diagnosis and post-therapeutic evaluation of AVMs in extremities.

• Journal of Plant Biotechnology
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• v.34 no.4
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• pp.339-346
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• 2007

Pollen germination viability is an essential factor to produce seeds from pollination and fertilization, which are required to maintain plant generation. In this study, we tried to identify the effect of boric acid on pollen germination and tube grouch in non-transgenic and transgenic plants expressing monoclonal antibodies (anti-colorectal cancer mAb CO17-1A, anti-breast cancer mAb BR55, and anti-rabies virus mAb57). The pollen of non-transgenic plant was treated with different concentration of boric acid (0, 5, 10, 15, 20, $40{\mu}g/mL$) in germination buffer to investigate its effect on in vitro pollen germination. At $20{\mu}g/mL$ of boric acid, tile pollen germination rate was the highest (49.5%) compared to other concentrations. In general, the germination rate significantly increased 3-10 folds in boric acid ($20{\mu}g/mL$) treated group in non-transgenic and transgenic plants. Also, the pollen tube length increased in boric acid ($20{\mu}g/mL$) treated groups. In the treated group, the pollen tube length increased until 3 h boric acid treatment and decreased after the 3 h, indicating that the 3 h is the most appropriate incubation time period. Western blot analysis showed that the mAb transgene expression was more stable in leaf than pollen in transgenic plants. This study suggested that $20{\mu}g/mL$ of boric acid is ideal concentration to induce in vitro pollen germination of transgenic plants expressing therapeutic monoclonal antibodies, indicating stable pollination and fertilization in transgenic plants.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.261-271
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• 2016

Citrus is an economically important fruit crop widely growing worldwide. However, citrus production largely depends on natural hybrid selection and bud sport mutation. Unique botanical features including long juvenility, polyembryony, and QTL that controls major agronomic traits can hinder the development of superior variety by conventional breeding. Diverse factors including drastic changes of citrus production environment due to global warming and changes in market trends require systematic molecular breeding program for early selection of elite candidates with target traits, sustainable production of high quality fruits, cultivar diversification, and cost-effective breeding. Since the construction of the first genetic linkage map using isozymes, citrus scientists have constructed linkage maps using various DNA-based markers and developed molecular markers related to biotic and abiotic stresses, polyembryony, fruit coloration, seedlessness, male sterility, acidless, morphology, fruit quality, seed number, yield, early fruit setting traits, and QTL mapping on genetic maps. Genes closely related to CTV resistance and flesh color have been cloned. SSR markers for identifying zygotic and nucellar individuals will contribute to cost-effective breeding. The two high quality citrus reference genomes recently released are being efficiently used for genomics-based molecular breeding such as construction of reference linkage/physical maps and comparative genome mapping. In the near future, the development of DNA molecular markers tightly linked to various agronomic traits and the cloning of useful and/or variant genes will be accelerated through comparative genome analysis using citrus core collection and genome-wide approaches such as genotyping-by-sequencing and genome wide association study.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.347-358
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• 2016

Brassinosteroid (BR), a plant steroid hormone, plays key roles in numerous growth and developmental processes as well as tolerance to both abiotic and biotic stress. To understand the biological networks involved in BR-mediated signaling pathways and stress tolerance, we performed comparative genome-wide transcriptome analysis of a constitutively activated BR bes1-D mutant with an Agilent Arabidopsis $4{\times}44K$ oligo chip. As a result, we newly identified 1,091 (562 up-regulated and 529 down-regulated) significant differentially expressed genes (DEGs). The combination of GO enrichment and protein network analysis revealed that stress-related processes, such as metabolism, development, abiotic/biotic stress, immunity, and defense, were critically linked to BR signaling pathways. Among the identified gene sets, we confirmed more than a 6-fold up-regulation of NB-ARC and FLS2 in bes1-D plants. However, some genes, including TIR1, TSA1 and OCP3, were down-regulated. Consistently, BR-activated plants showed higher tolerance to drought stress and pathogen infection compared to wild-type controls. In this study, we newly developed a useful, comprehensive method for large-scale identification of critical network and gene sets with global transcriptome analysis using a microarray. This study also showed that gain of function in the bes1-D gene can regulate the adaptive response of plants to various stressful conditions.