Molecular Insights into Abiotic Stresses in Mango

Mango (Mangifera indica L.) is one of the most economically important fruit crops across the world, mainly in the tropics and subtropics of Asia, Africa, and Central and South America. Abiotic stresses are the prominent hindrance that can adversely affect the growth, development, and significant yield loss of mango trees. Understanding the molecular physiological mechanisms underlying abiotic stress responses in mango is highly intricate. Therefore, to gain insights into the molecular basis and to alleviate the abiotic stress responses to enhance the yield in the mere future, the use of high-throughput frontier approaches should be tied along with the baseline investigations. Taking these gaps into account, this comprehensive review mainly speculates to provide detailed mechanisms and impacts on physiological and biochemical alterations in mango under abiotic stress responses. In addition, the review emphasizes the promising omics approaches in unraveling the candidate genes and transcription factors (TFs) responsible for abiotic stresses. Furthermore, this review also summarizes the role of different types of biostimulants in improving the abiotic stress responses in mango. These studies can be undertaken to recognize the roadblocks and avenues for enhancing abiotic stress tolerance in mango cultivars. Potential investigations pointed out the implementation of powerful and essential tools to uncover novel insights and approaches to integrate the existing literature and advancements to decipher the abiotic stress mechanisms in mango. Furthermore, this review serves as a notable pioneer for researchers working on mango stress physiology using integrative approaches.

First report of root mat disease in a hydroponic tomato production system caused by rhizogenic Agrobacterium biovar 1 in South Korea

In June 2019, root mat disease was observed in hydroponically cultivated tomatoes in Jinju, South Korea, which occurred in at least 30% of the plants in the greenhouse. To isolate the causal bacteria, 10 g of infested tomato root mat sample was ground with 50 mL of sterile water. A 100-µL aliquot of the homogenate was serially diluted and spread on Mannitol-Glutamate (MG) medium amended with 0.1% yeast extract (MGY) and incubated at 28°C for 48 hours. Fifteen dominant colonies that formed on the MGY medium were purified and subjected to diagnostic polymerase chain reaction (PCR) based on the virD2-ipt gene loci. Because Ti-plasmid harbors both virD2 and ipt genes, Ri-plasmid-borne Agrobacterium species with only virD2 can be differentiated using virD2-ipt PCR. To amplify virD2, the primers 5'-ATG CCC GAT CGA GCT CAA GT-3' and 5'-TCG TCT GGC TGA CTT TCG TCA TAA-3' were used; for ipt amplification, the primers 5'-GAT CG(G/C) GTC CAA TG(C/T) TGT-3' and 5'-GAT ATC CAT CGA TC(T/C) CTT-3' were used. Amplification involved an initial 94°C for 1 min and then 40 cycles at 94°C, 50°C, and 72°C for 1 min at each temperature, with a final 5-min extension at 72°C. For three strains (GNIY2, J10, and J11), virD2 PCR products, but no ipt PCR products, were identified, indicating that three strains are Ri-plasmid-borne Agrobacterium species. A pathogenicity test was performed on 2-week-old tomato plants. Bacteria isolates (GNIY2, J10, and J11) cultured overnight in LB were made into a bacterial suspension (107 cfu/mL) in 50 mM phosphate buffer. Five tomato seedling roots were cut with sterilized scissors and soaked in each bacterial suspension for 1 hour. Phosphate buffer was used as a negative control. The inoculated tomato seedlings were transplanted in new pots and placed in a greenhouse with 25°C day and 20°C night temperature set points in natural light. After 9 weeks, all inoculated tomato plants produced overgrown roots, while the negative control plants had no symptoms. To satisfy Koch's postulates, re-isolation was performed from the diseased tomato and was the re-isolated bacteria were subject to partial 16S rDNA sequencing. Biovar tests performed as previously described revealed that all three isolates were biovar 1. A representative strain (GNIY2) was deposited in the Korean Agricultural Culture Collection (KACC 21759). To confirm the identity, four housekeeping genes of KACC 21759 were sequenced (16S rRNA, trpE, rpoB, and recA) and deposited in GenBank (accession nos. MT071560, MT444428, MT444429, and MT444430). Multilocus sequence analysis performed as previously described showed that the KACC 21759 strain was grouped in Agrobacterium genomospecies 4. This is the first report on mat root disease caused by Agrobacterium biovar 1 in hydroponic tomatoes in South Korea.

847Interim analysis of the device-detected cardiac tachyarrhythmic events and sleep-disordered breathing (DEDiCATES)" study; focused on baseline characteristics

Funding Acknowledgements

This work is supported by Boston Scientific.

Background/introduction: Sleep-disordered breathing (SDB) is one of the common comorbidities in cardiac implantable electronic devices (CIED) patients. It’s feasible to detect SDB using specialized diagnostic function of CIEDs showing comparable performance in diagnostic accuracy of SDB to conventional polysomnography. To date, few studies have investigated the prognostic value of CIED-detected SDB in cardiovascular risk.

Purpose

In the Device-Detected CArdiac Tachyarrhythmic events and Sleep-disordered breathing (DEDiCATES) study, we aim to determine whether device-detected sleep-disordered breathing (SDB) events are associated with increased risk of cardiac arrhythmias or other cardiovascular (CV) outcomes. Here, we present interim baseline data of the study population to investigate the baseline prevalence and severity of device-detected SDB in CIED patients.

Methods

The study was designed as a prospective, multicenter, and observational study to include 600 patients. Eligible patients have dual chamber CIEDs with SDB detection function which reports the average number of sleep disturbance events per hour per night in the form of a Respiratory Disturbance Index (RDI). The daily RDI values were collected to measure the severity and burden of SDB. The baseline severity of SDB was determined according to RDI data recorded during the first 1 week, 1 month, and 3 ± 1 months after CIED implantation; patients with RDI≥ 30/h for at least one night are classified into the severe SDB group. 

Results

A total of 313 patients who completed the first device interrogation at 3 ± 1 months were included for analysis. The mean age and CHA2DS2VASc score were 69 and 3.1, respectively. Forty-nine percent of patients were men, and 35.5% were classified as high risk for SDB by Berlin questionnaire. The rate of severe SDB increased with longer monitoring period (83.8% at 1week, 91.6% at 1 month, and 96.4% at 3 ± 1 months). There was no baseline demographic difference between the severe and non-severe SDB groups, except that baseline body mass index (BMI) was higher in the severe group (24.5% vs. 21.5%, p = 0.01). The mean RDI was 36.3, 34.2, and 33.0 per night during the first 1 week, 1 month, and 3 ± 1 months, respectively. Considering the limitation of the categorical criteria of baseline severity, we arbitrarily reclassified the patients according to median mean RDI value. Men were more frequent and BMI was higher in the above-mean RDI group compared to the below-mean RDI group. Using logistic regression analysis, we identified that BMI and male gender were associated with patients with above-mean RDI.

Conclusions

Conventional categorical classification of SDB severity seems to be limited in its ability to discriminate high risk patients. Thus, more suitable RDI-related variables need to be identified in future outcome analysis.

Abstract Figure. Prevalence of baseline severe SDB

Derivation of trophoblast stem cells from naïve human pluripotent stem cells

Naïve human pluripotent stem cells (hPSCs) provide a unique experimental platform of cell fate decisions during pre-implantation development, but their lineage potential remains incompletely characterized. As naïve hPSCs share transcriptional and epigenomic signatures with trophoblast cells, it has been proposed that the naïve state may have enhanced predisposition for differentiation along this extraembryonic lineage. Here we examined the trophoblast potential of isogenic naïve and primed hPSCs. We found that naïve hPSCs can directly give rise to human trophoblast stem cells (hTSCs) and undergo further differentiation into both extravillous and syncytiotrophoblast. In contrast, primed hPSCs do not support hTSC derivation, but give rise to non-self-renewing cytotrophoblasts in response to BMP4. Global transcriptome and chromatin accessibility analyses indicate that hTSCs derived from naïve hPSCs are similar to blastocyst-derived hTSCs and acquire features of post-implantation trophectoderm. The derivation of hTSCs from naïve hPSCs will enable elucidation of early mechanisms that govern normal human trophoblast development and associated pathologies.

Changes in Total Plate Counts and Quality of Pig Small Intestine by Different Washing and Packaging Methods

Pig small intestine not only is used as food but also for sausage casings production in many countries worldwide. However, it is well recognized that the small intestine is important source of spoilage and pathogenic bacteria. The present study aimed at investigating the effects of different washing and packaging methods on the changes of microbial levels and physicochemical characteristics of pig small intestine. After collecting and trimming off of visible fats, the pig small intestine samples were treated with; (i) different packaging methods: aerobic packaging (AP), skin packaging (SP), and vacuum packaging (VP); and (ii) washing with different concentrations of acetic acid. The treated samples were then stored at 4℃ for 1, 4, 7, and 10 d. At 1-d storage, higher pH value was found in the AP-treated samples, however, after 7 to 10 days the samples treated with SP had higher values compared to the ones treated with AP and VP (p<0.05). Thiobarbituric acid reactive substances values were higher in the AP-treated samples than those of the SP- and VP- treated samples at 7-d storage (p<0.05). At 10th d, total plate counts (TPC) were higher in the control than in the acetic acid-washed samples (p<0.05). Additionally, the TPC was lower in the SP- and VP-treated samples than the AP-treated samples at 7-d storage (p<0.05). These obtained results suggest that the applications of washing with acetic acid solution and/or SP and VP methods could be an effective way to extend the shelf-life of pig small intestine during cold distribution.

Near-infrared angiography for critical limb ischemia in a diabetic murine model

Peripheral arterial disease (PAD) is a highly prevalent disease process that afflicts more than 20% of individuals with diabetes. Progression of PAD in the setting of diabetes can lead to critical limb ischemia (CLI), which is associated with increased risk of wounds, gangrene, and limb loss. Prompt noninvasive evaluation of limbs affected by PAD progression and CLI is currently limited. Here, we evaluate the utility of a custom-designed multispectral imaging system for fluorescence-based near-infrared angiography and compare it to the existing gold standard of laser-scanning Doppler perfusion assessments. Due to its higher resolution and fluorescence sensitivity, near-infrared angiography demonstrates a greater capacity to characterize altered dynamic arterial perfusion in a clinically relevant diabetic murine model for CLI. Furthermore, we demonstrate that our imaging system can accurately track arterial perfusion recovery over time following induced ischemia, and reveal unique phenotypic differences in the setting of diabetes.

A New Chemical Compound, NecroX-7, Acts as a Necrosis Modulator by Inhibiting High-Mobility Group Box 1 Protein Release During Massive Ischemia-Reperfusion Injury

BACKGROUND

Necrotic cell death is common in a wide variety of pathologic conditions, including ischemia-reperfusion (IR) injury. The aim of this study was to develop an IR injury-induced hepatic necrosis model in dogs by means of selective left hepatic inflow occlusion and to test the efficacy of a new chemical compound, NecroX-7, against the IR injury-induced hepatic damage.

METHODS

A group of male Beagle dogs received intravenous infusions of either vehicle or different doses of NecroX-7 (1.5, 4.5, or 13 mg/kg) for a 20-minute period before a 90-minute left hepatic inflow occlusion followed by reperfusion.

RESULTS

The gross morphology in the NecroX-7-treated groups after occlusion appeared to be less congested and less swollen than that in vehicle-treated control group. Circulating alanine transaminase and aspartate transaminase levels in the control group were elevated during the course of IR, and were effectively blocked in the 4.5 and 13 mg/kg NecroX-7-treated groups. The serum levels of high-mobility group box 1 protein showed a peak at 8 hours after occlusion in control group, and this elevation was significantly blunted by 4.5 mg/kg NecroX-7 treatment. Histologic analysis showed a marked ischemia or IR injury-induced hepatocytic degenerations, sinusoidal and portal vein congestions, and inflammatory cell infiltrations in the control group, whereas the treatment groups showed significantly diminished histopathology in a dose-dependent manner.

CONCLUSIONS

These results demonstrated that NecroX-7 attenuated the hepatocyte lethality caused by hepatic IR injury in a large animal setting. We conclude that NecroX-7 may provide a wide variety of therapeutic options for IR injury in human patients.

Abstract 312: Arterial CEPT1 Expression Correlates With Diabetes and Atherosclerotic Occlusive Disease

Choline/ethanolamine phosphotransferase-1 (CEPT1) is a ubiquitously expressed enzyme that catalyzes the final step in synthesis of the majority of mammalian phospholipids, that are known to also impact atheroprogression. We previously found that in the setting of diabetes CEPT1 expression and downstream phospholipid biosynthesis are critically altered in hepatocytes. We therefore hypothesized that in diabetes CEPT1 expression is also altered in arterial tissue, and correlates with disease severity. To test this hypothesis we evaluated CEPT1 protein expression in murine and human arterial tissue in the presence or absence of diabetes, and/or advanced occlusive disease. CEPT1 expression in the aorta of Db/Db mice was 43% increased relative to Wt controls (n=7 per mouse group;p=0.03). On the other hand, CEPT1 expression was not significantly altered in Db/Db myocardial or skeletal muscle (p=0.2 and p=0.09, respectively). To determine whether our findings translate to similar CEPT1 expression patterns in human arterial tissue, we harvested carotid artery intima from 11 diabetic and 7 non-diabetic patients undergoing carotid endarterectomy (CEA). We also harvested peripheral arterial segments with minimal and maximal atherosclerotic occlusive disease from 8 diabetic and 4 non-diabetic patients undergoing lower extremity amputation. Relative to non-diabetic patients, patients who were diabetic had increased CEPT1 expression in CEA tissue (53% increase;p=0.05), and peripheral arterial segments (36% increase;p=0.04). Interestingly, relative to peripheral arteries with minimal atherosclerotic occlusive disease, segments with maximal disease had a two-fold increase in CEPT1 expression (p<0.01). Analysis of maximally diseased peripheral arteries demonstrated significantly higher CEPT1 expression among diabetic patients (34% increase;p=0.03). There was no difference in CEPT1 expression in minimally diseased arteries of diabetic and non-diabetic patients (p=0.1). These findings highlight that increased CEPT1 expression correlates with diabetes and extent of arterial occlusive disease. Furthermore, they argue that CEPT1 is a unique arterial tissue biomarker for occlusive disease severity.

Hepatic differentiation of porcine embryonic stem cells for translational research of hepatocyte transplantation

Porcine embryonic stem cells (ES) are considered attractive preclinical research tools for human liver diseases. Although several studies previously reported generation of porcine ES, none of these studies has described hepatic differentiation from porcine ES. The aim of this study was to generate hepatocytes from porcine ES and analyze their characteristics. We optimized conditions for definitive endoderm induction and developed a 4-step hepatic differentiation protocol. A brief serum-free condition with activin A efficiently induced definitive endoderm differentiation from porcine ES. The porcine ES-derived hepatocyte-like cells highly expressed hepatic markers including albumin and α-fetoprotein, and displayed liver characteristics such as glycogen storage, lipid production, and low-density lipoprotein uptake. For the first time, we describe a highly efficient protocol for hepatic differentiation from porcine ES. Our findings provide valuable information for translational liver research using porcine models, including hepatic regeneration and transplant studies, drug screening, and toxicology.

Abstract POSTER-BIOL-1328: Endothelin-1/endothelin a receptor-mediated biased signaling is a new player in modulating human ovarian cancer cell tumorigenesis

The endothelin-1 (ET-1)/endothelin A receptor (ETAR, a G protein-coupled receptor) axis confers pleiotropic effects on both tumor cells and the tumor microenvironment, modulating chemo-resistance and other tumor-associated processes by activating Gαq- and β-arrestin-mediated pathways. While the precise mechanisms by which these effects occur remain to be elucidated, interference with ETAR signaling has emerged as a promising antitumor strategy in many cancers including ovarian cancer (OC). However, current clinical approaches using ETAR antagonists in the absence of a detailed knowledge of downstream signaling have resulted in multiple adverse side effects and limited therapeutic efficacy. To maximize the safety and efficacy of ETAR-targeted OC therapy, we investigated the role of other G protein subunits such as Gαs in the ETAR-mediated ovarian oncogenic signaling. In HEY (human metastatic OC) cells where the ET-1/ETAR axis is well-characterized, Gαs signaling inhibits ETAR-mediated OC cell migration, wound healing, proliferation and colony formation on soft agar while inducing OC cell apoptosis. Mechanistically, ET-1/ETAR is coupled to Gαs/cAMP signaling in the same ovarian carcinoma-derived cell line. Gαs/cAMP/PKA activation inhibits ETAR-mediated β-arrestin activation of angiogenic/metastatic Calcrl and Icam2 expression. Consistent with our findings, Gαs overexpression is associated with improved survival in OC patients in the analysis of the Cancer Genome Atlas data. In conclusion, our results indicate a novel function for Gαs signaling in ET-1/ETAR-mediated OC oncogenesis and may provide a rationale for a biased signaling mechanism, which selectively activates Gαs-coupled tumor suppressive pathways while blocking Gαq-/β-arrestin-mediated oncogenic pathways, to improve the targeting of the ETAR axis in OC.

Citation Format: Jian-peng Teoh, Kyoung-mi Park, Yongchao Wang, Qiuping Hu, Sangmi Kim, Guangyu Wu, Shuang Huang, Nita Maihle, Il-man Kim. Endothelin-1/endothelin a receptor-mediated biased signaling is a new player in modulating human ovarian cancer cell tumorigenesis [abstract]. In: Proceedings of the 10th Biennial Ovarian Cancer Research Symposium; Sep 8-9, 2014; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2015;21(16 Suppl):Abstract nr POSTER-BIOL-1328.

MicroRNA-150 deletion in mice protects kidney from myocardial infarction-induced acute kidney injury

Despite greater understanding of acute kidney injury (AKI) in animal models, many of the preclinical studies are not translatable. Most of the data were derived from a bilateral renal pedicle clamping model with warm ischemia. However, ischemic injury of the kidney in humans is distinctly different and does not involve clamping of renal vessel. Permanent ligation of the left anterior descending coronary artery model was used to test the role of microRNA (miR)-150 in AKI. Myocardial infarction in this model causes AKI which is similar to human cardiac bypass surgery. Moreover, the time course of serum creatinine and biomarker elevation were also similar to human ischemic injury. Deletion of miR-150 suppressed AKI which was associated with suppression of inflammation and interstitial cell apoptosis. Immunofluorescence staining with endothelial marker and marker of apoptosis suggested that dying cells are mostly endothelial cells with minimal epithelial cell apoptosis in this model. Interestingly, deletion of miR-150 also suppressed interstitial fibrosis. Consistent with protection, miR-150 deletion causes induction of its target gene insulin-like growth factor-1 receptor (IGF-1R) and overexpression of miR-150 in endothelial cells downregulated IGF-1R, suggesting miR-150 may mediate its detrimental effects through suppression of IGF-1R pathways.

Expression pattern analysis of hepatocellular carcinoma tumor markers in viral hepatitis B and C patients undergoing liver transplantation and resection

BACKGROUND

This study was conducted to compare the expression patterns of serum alpha-fetoprotein (AFP) and proteins induced by vitamin K absence or antagonist-II (PIVKA-II) in hepatocellular carcinoma (HCC) patients undergoing liver transplantation (LT) and resection at a high-volume single institution.

METHODS

First, 663 liver transplant recipients with HCC were selected. They were divided into hepatitis B virus (HBV) (n = 628) and hepatitis C virus (HCV) groups (n = 35). Their medical records were retrospectively reviewed. Second, another cohort of 2709 patients who underwent HCC resection included 2258 HBV, 143 HCV, and 308 non-HBV non-HCV (NBNC) patients.

RESULTS

In the transplantation group, pretransplantation AFP level >20 ng/mL was observed in 42.5% of HBV patients and 60% of HCV patients (P = .042). PIVKA-II level >40 mAU/mL was observed in 30.6% of HBV patients and 42.9% of HCV patients (P = .127). In the resection group, a preoperative AFP level >20 ng/mL was observed in 51.7% of HBV patients and 43.3% of HCV patients (P = .052). PIVKA-II level >40 mAU/mL was observed in 59.7% of HBV patients and 56.6% of HCV patients (P = .47). Preoperative AFP level >20 ng/mL and PIVKA-II level >40 mAU/mL were observed in 35.7% and 61% of NBNC patients, respectively. Receiver-operator characteristic curve analyses revealed that the expression pattern of PIVKA-II in patients with elevated AFP level was not predictable and vice versa, regardless of background liver diseases.

CONCLUSIONS

This study indicates that serum AFP and PIVKA-II may be expressed variably regardless of the types of background liver disease. Further large-volume multicenter studies are needed to evaluate the possibility of the etiology-dependent expression of tumor markers.

Distribution Channel and Microbial Characteristics of Pig By-products in Korea

The distribution channel of meat by-products from the pig farm to the final consumer can include a meat processor, wholesale market, wholesaler, retailer, and butcher shop. Bacterial contamination at any of these steps remains to be a serious public health concern. The aim of this study was to evaluate the distribution channel and microbial characteristics of pig by-products in Korea. Upon evaluation of pig by-products in cold storage, we found that the small and large intestine were significantly (p<0.05) higher in pH value compared to the heart and liver. The total plate counts were not significantly different among offals until cold storage for 7 d. The coliform count after 1 d of cold storage was significantly (p<0.05) higher in small and large intestine than in the other organs. The coliform count of heart, liver, and stomach showed a higher coliform count than small and large intestine until 7 d of cold storage. As determined by 16S rRNA sequencing, contamination of major pig by-products with Escherichia coli, Shigella spp., and other bacterial species occurred. Therefore, our results suggest that a more careful washing process is needed to maintain quality and hygiene and to ensure the safety of pig by-products, especially for small and large intestine.

Endothelin-1/endothelin A receptor-mediated biased signaling is a new player in modulating human ovarian cancer cell tumorigenesis

The endothelin-1 (ET-1)/endothelin A receptor (ETAR, a G protein-coupled receptor) axis confers pleiotropic effects on both tumor cells and the tumor microenvironment, modulating chemo-resistance and other tumor-associated processes by activating Gαq- and β-arrestin-mediated pathways. While the precise mechanisms by which these effects occur remain to be elucidated, interference with ETAR signaling has emerged as a promising antitumor strategy in many cancers including ovarian cancer (OC). However, current clinical approaches using ETAR antagonists in the absence of a detailed knowledge of downstream signaling have resulted in multiple adverse side effects and limited therapeutic efficacy. To maximize the safety and efficacy of ETAR-targeted OC therapy, we investigated the role of other G protein subunits such as Gαs in the ETAR-mediated ovarian oncogenic signaling. In HEY (human metastatic OC) cells where the ET-1/ETAR axis is well-characterized, Gαs signaling inhibits ETAR-mediated OC cell migration, wound healing, proliferation and colony formation on soft agar while inducing OC cell apoptosis. Mechanistically, ET-1/ETAR is coupled to Gαs/cAMP signaling in the same ovarian carcinoma-derived cell line. Gαs/cAMP/PKA activation inhibits ETAR-mediated β-arrestin activation of angiogenic/metastatic Calcrl and Icam2 expression. Consistent with our findings, Gαs overexpression is associated with improved survival in OC patients in the analysis of the Cancer Genome Atlas data. In conclusion, our results indicate a novel function for Gαs signaling in ET-1/ETAR-mediated OC oncogenesis and may provide a rationale for a biased signaling mechanism, which selectively activates Gαs-coupled tumor suppressive pathways while blocking Gαq-/β-arrestin-mediated oncogenic pathways, to improve the targeting of the ETAR axis in OC.

Abstract O-3: A β1-Adrenergic Receptor/β-Arrestin1-Regulatable MicroRNA, MiR-150 Protects the Mouse Heart from Ischemic Injury by Repressing Pro-apoptotic Egr2 and P2x7r

MicroRNA (miR)-150 is down-regulated in patients with acute myocardial infarction (AMI), atrial fibrillation, dilated and ischemic cardiomyopathy as well as in various mouse heart failure (HF) models. Circulating miR-150 has been recently proposed as a better biomarker of HF than clinically used markers such as brain natriuretic peptide. We recently showed that β-arrestin1-biased β1-adrenergic receptor (β1AR) cardioprotective signaling activated by the β-arrestin-biased β-blocker, carvedilol (Carv) stimulates the processing of miR-150 in the heart (see figure A). However, the potential role of miR-150 in ischemic injury and HF is unknown. Here, we show that genetic deletion of miR-150 in mice causes abnormalities in cardiac structural and functional remodeling after MI. The cardioprotective roles of miR-150 during ischemic injury were attributed to repression of the pro-apoptotic genes egr2 (zinc binding transcription factor induced by ischemia) and p2x7r (pro-inflammatory ATP receptor) [see figure B]. These findings reveal a pivotal role for miR-150 as a regulator of cardiomyocyte survival during cardiac injury. In conclusion, our study will help to stratify HF patients that may respond better to β-arrestin-biased β-blockers, which is guided by circulating levels of miR-150.

The natural history of arteriovenous access and risk factors associated with access thrombosis after successful kidney transplantation

INTRODUCTION

The purpose of this study was to determine the natural history of arteriovenous (AV) access after successful kidney transplantation (KT) and to identify the risk factors of spontaneous access closure in kidney transplant recipients.

METHODS

We performed a retrospective review of 115 patients who underwent KT with functioning access from June 2010 to July 2012. AV access patency was checked and recorded daily during the hospital stay and at every visit to the outpatient clinic. Patients were divided into 2 groups according to the patency of access, and risk factors of access thrombosis were assessed. Access patency was followed up until patency was lost or the study was closed.

RESULTS

At the end of follow-up, 18 (15.7%) AV accesses had spontaneously closed. Mean time to closure was 119 ± 163 days, and 12 of 18 were closed within 90 days after KT. AV access spontaneously closed in 8.5% of male patients, compared with 27.3% of female patients (P = .007), 12.2% of cases with native access compared with 35.3% of cases with artificial access (P = .016), and 11.3% of cases with wrist access compared with 25.7% of cases with elbow access (P = .049). Spontaneously closed AV accesses tended to have a lower mean access flow compared with functioning accesses (P = .019). On multivariate analysis, female sex and AV access flow volume affected spontaneous AV access closure (odds ratio 4.749, 95% confidence interval 1.919-35.383, P = .008; odds ratio 0.998, 95% confidence interval 0.996-0.999, P = .010, respectively).

CONCLUSIONS

Our results suggest that AV access thrombosis occurs more frequently during the early postoperative period, particularly in female patients or patients with low flow access, whereas it is a rare event in male patients or patients with high access flow, especially in the late postoperative period.

Effects of high pressure processing on fatty acid composition and volatile compounds in Korean native black goat meat

This study investigated the effects of high pressure processing (HPP) on fatty acid composition and volatile compounds in Korean native black goat (KNBG) meat. Fatty acid content in KNBG meat was not significantly (p > 0.05) different among the control goats and those subjected HPP. The 9,12-octadecadienoic acid and octadecanoic acid, well-known causes of off-flavors, were detected from meat of some KNBG. A difference between the control and HPP treatment was observed in the discriminated function analysis using an electronic nose. The results suggest that the volatile compounds in KNBG meat were affected by HPP.

Abstract A44: Endothelin A receptor-mediated biased signaling is a new player in modulating ovarian cancer progression

Ovarian cancer (OC) is the leading cause of gynecological cancer deaths among women in the United States. Although there has been major progress in our understanding of the biology and molecular genetics of OC, mortality rate has not been significantly improved in the past decades. Hence, introduction of new agents and refinement of existing targeted therapies through advancing biological insights are warranted. The endothelin-1 (ET-1)/endothelin A receptor (ETAR, a G protein-coupled receptor [GPCR]) axis confers pleiotropic effects on both tumor cells and tumor microenvironments, modulating epithelial to mesenchymal transition, chemo-resistance, and other tumor-associated processes through activating Gαq- and β-arrestin-mediated pathways. Because ETAR is ubiquitously expressed in the body, the current therapeutic approach to OC using ETAR antagonists without detailed knowledge of downstream signaling is prone to adverse side effects and reduced efficiency. In order to tackle the challenges ahead in terms of successful clinical application, this project seeks to employ the concept of “biased GPCR signaling”, in which β-arrestin-biased ligands and G protein-biased ligands demonstrate unique pharmacological properties that allow selective blocking of undesired complications while maintaining desired effects. The ability of biased ligands to differentially activate different signaling pathways via the same receptor raises the possibility of manipulating existing ETAR antagonists to achieve selective induction of favorable signaling pathways. The roles of individual G protein subunits such as Gαs in ETAR-mediated OC progression were therefore investigated in order to define tumor suppressive and oncogenic downstream effects. We hypothesized that Gαs-coupled signaling of ETAR confers tumor suppressive effects on OC.

Methods: To identify the roles of Gαs and Gαq in ETAR-mediated in vitro tumorigenesis, HEY (human ovarian cancer) cells endogenously overexpressing ETAR were pre-treated with pharmacological agents including forskolin (adenylate cyclase activator inducing PKA signaling), H-89 (PKA inhibitor), PMA (PKC activator), and Ro-318425 (PKC inhibitor) followed by ET-1 stimulation. We then performed cell migration, TUNEL, wound healing, and soft agar assays to test our hypothesis. Genetic gain- and loss-of-function studies using expression plasmids and lentiviral shRNAs for G proteins and β-arrestins were also performed.

Results: Consistent with previous studies, HEY cells treated with ET-1 showed an increase in cell proliferation and migration and ETAR-mediated β-arrestins signaling pathways induced OC cell migration. We also confirmed the oncogenic roles of Gαq-mediated ETAR signaling. Interestingly, Gαs-coupled ETAR signaling was found to inhibit OC cell migration, wound healing and colony formation on soft agars, but induced OC cell apoptosis. Genetic functional studies also demonstrated that ETAR-mediated Gαs signaling pathways inhibited OC cell migration, indicating its novel tumor suppressive effects in OC.

Conclusion: Our data suggest that biased signaling in ETAR is a plausible strategy to refine the existing ETAR antagonists for OC. The identification of Gαs-coupled ETAR signaling as a novel tumor suppressive signaling pathway will contribute to the development of improved ligand therapies for OC with more sustained efficacy. This novel discovery will enable a greater understanding of cancer biology, thereby facilitating the pursuit of biased signaling mechanisms in ETAR-mediated OC therapies.

Citation Format: Jian-peng Teoh, Yongchao Wang, Yaoping Tang, Kyoung-mi Park, Il-man Kim. Endothelin A receptor-mediated biased signaling is a new player in modulating ovarian cancer progression. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: From Concept to Clinic; Sep 18-21, 2013; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2013;19(19 Suppl):Abstract nr A44.

Abstract 057: β-arrestin1-Biased β1-adrenergic Receptor Signaling Regulates MicroRNA Processing

MicroRNAs (miRs) are small, non-coding RNAs that function to post-transcriptionally regulate gene expression. First transcribed as long primary transcripts (pri-miRs), they are processed in the nucleus by Drosha into hairpin intermediates (pre-miRs) and further processed in the cytoplasm by Dicer into mature miRs where they regulate cellular processes following activation by a variety of signals such as those stimulated by β-adrenergic receptors (βARs). Initially discovered to desensitize βAR signaling, β-arrestins are now appreciated to transduce multiple effector pathways independent of G protein-mediated second messenger accumulation, a concept known as biased signaling. We previously showed that the β-arrestin-biased βAR agonist carvedilol activates cellular pathways in the heart. Here, we tested the hypothesis that carvedilol could activate β-arrestin-mediated miR maturation, thereby providing a novel potential mechanism for its cardioprotective effects. In human cells and mouse hearts, carvedilol (Carv) upregulates a subset of mature and pre-miRs but not their pri-miRs in a β1AR-, G protein-coupled receptor kinase (GRK) 5/6- and β-arrestin1-dependent manner (see figure). Mechanistically, β-arrestin1 regulates miR processing by forming a nuclear complex with hnRNPA1, a component of the Drosha microprocessor complex (see figure). In conclusion, our findings indicate a novel function for β1AR-mediated β-arrestin1 signaling in miR biogenesis, which may be linked to its cell survival mechanism and beneficial adaptive remodeling in the failing heart.

Porcine bioengineered scaffolds as new frontiers in regenerative medicine

Porcine organs are attractive for xenotransplantation, if severe immunologic concerns can be overcome. Recently, reengineered organs, with heterologous cellular materials removed but preserved organ architecture and vasculature have been created using small rodents in an effort to produce customized bioengineered organs. However, few studies have been performed to generate bioengineered organs from porcine sources. The aim of this work was to produce 3-D bioengineered scaffolds from major porcine organs, preserving the native morphology and vascular structures with complete removal of cellular and nuclear materials. We decellularized porcine heart, liver, and kidney using a peristaltic pump system with 1% sodium dodecyl sulfate. The preservation of major architecture and vasculature was confirmed by gross findings, ultrasonography, and angiography. Hematoxylin and eosin staining revealed no evidence of nuclear or cytoplasmic residues. Quantitative DNA analysis demonstrated a substantial reduction (0%-8%) of porcine DNA in the scaffolds. These results suggested that 3-D bioengineered scaffolds of porcine organs may have tremendous potential to produce non-immunogenic transplantable organs as well as beneficial tools for biomedical studies on organ re-engineering and repair.

Comparison of open and laparoscopic live donor left lateral sectionectomy

BACKGROUND

The present study was undertaken to determine whether laparoscopic live donor left lateral sectionectomy (LLS) in paediatric liver transplantation is a feasible, safe and reproducible procedure, compared with open live donor left lateral sectionectomy (OLS).

METHODS

A retrospective review was conducted of all consecutive live donor procedures for paediatric liver transplantation performed between May 2008 and October 2009. All live donor hepatectomies were carried out by a single surgeon.

RESULTS

A total of 26 live donor procedures for paediatric liver transplantation were performed, of which 11 were LLS and 11 OLS; four left hepatectomies were excluded. The LLS group had a significantly shorter hospital stay (mean(s.d.) 6·9(0·3) versus 9·8(0·9) days; P = 0·001) and time to oral diet (2·1(0·3) versus 2·7(0·4) days; P = 0·012). Duration of operation, blood loss, warm ischaemia time and out-of-pocket medical costs were comparable between groups. There was no death in either donor group and only one complication, a wound seroma, in the OLS group.

CONCLUSION

LLS seemed to be a safe, feasible and reproducible procedure, and was associated with reduced hospital stay.

Effect of necrosis modulator necrox-7 on hepatic ischemia-reperfusion injury in beagle dogs

OBJECTIVE

The liver is susceptible to ischemia-reperfusion (IR) injury during inflow occlusion for hepatectomy. There is no effective pharmacologic agent available to prevent the release of high-mobility-group box 1 (HMGB1) or to ameliorate IR injury. This pilot study sought to develop a model in beagle dogs for the purpose of testing the efficacy of a necrosis modulator, necrox-7, to prevent hepatic IR injury in beagle dogs.

METHODS

Six male beagle dogs were randomly assigned to the control group (group A; n = 3) or the treatment group (group B; n = 3). Under general anesthesia, group B received intravenous infusion of necrox-7 (13 mg/kg over 20 minutes) followed by 60 minutes of left hepatic inflow occlusion and 60 minutes of reperfusion. Both groups were tested for serum biochemicals, hematology values, liver biopsies, and plasma HMGB1 levels over a 48-hour period.

RESULTS

The maximum alanine transferase (ALT), aspartate transferase (AST), and lactate dehydrogenase (LDH) levels among group A versus group B were: ALT 868.3 ± 337.4 IU/L vs 274.3 ± 72.6 IU/L (P = .041); AST 1,024.7 ± 246.5 IU/L vs 505.3 ± 66.7 IU/L (P = .024); and LDH 962.7 ± 226.2 IU/L vs 552.7 ± 62.4 IU/L (P = .039). Liver biopsy demonstrated marked necrosis and inflammatory infiltrates in group A, whereas group B showed little evidence of IR injury. The plasma HMGB1 concentration was significantly lower among group B versus A.

CONCLUSION

This pilot study developed a hepatic IR injury model, demonstrating that necrox-7 reduced hepatic necrosis secondary to IR injury in a large animal setting.

In vitro inhibitory effects of Wen-pi-tang-Hab-Wu-ling-san on human cytochrome P450 isoforms

WHAT IS KNOWN AND OBJECTIVE

Although Wen-pi-tang-Hab-Wu-ling-san (WHW), an oriental herbal medicine, has been prescribed for the treatment of chronic renal failure (CRF) in Korean clinics, no studies regarding WHW-drug interactions had been reported. The purpose of this study was to evaluate the possibility that WHW inhibits the catalytic activities of major cytochrome P450 (CYP) isoforms.

METHODS

The abilities of various WHW extracts to inhibit phenacetin O-de-ethylation (CYP1A2), tolbutamide 4-methylhydroxylation (CYP2C9), omeprazole 4'-hydroxylation (CYP2C19), dextromethorphan O-demethylation (CYP2D6), chlorzoxazone 6-hydroxylation (CYP2E1) and midazolam 1-hydroxylation (CYP3A4) were assessed using human liver microsomes.

RESULTS AND DISCUSSION

WHW extract at concentrations up to 100 μm showed negligible inhibition of the six CYP isoforms tested (CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4), with apparent IC(50) values (concentration of the inhibitor causing 50% inhibition of the original enzyme activity) of 817.5, 601.6, 521.7, 310.2, 342.8 and 487.0 μg/mL, respectively.

WHAT IS NEW AND CONCLUSION

Our in vitro findings suggest that WHW extract at concentrations corresponding to a clinically recommended dosage range has no notable inhibitory effects on CYP isoforms. Therefore, we believe that WHW extract may be free of drug-herb interactions when co-administered with other medicines. However, in vivo human studies are needed to confirm these results.

The appearance of the adrenal glands on computed tomography in multiple endocrine neoplasia type 1

AIMS

To review the morphology of the adrenal glands in multiple endocrine neoplasia type 1 (MEN1) on computed tomography (CT) to compare the results with established normal values for adrenal size and nodularity and to correlate adrenal size with serum cortisol secretory dynamics.

MATERIALS AND METHODS

Two observers independently reviewed the adrenal CT in 28 patients with MEN1, measuring the maximum width of the body of the gland and the medial and lateral limbs. Incidence and location of nodules >5 mm within the gland were recorded. Following exclusion of known cases of Cushing's syndrome, adrenal gland size was compared with previously documented normative data. Adrenal gland size was compared between patients with normal and abnormal cortisol dynamics.

RESULTS

Comparison of mean adrenal size in MEN1 patients with normative data showed that the adrenal limbs were significantly larger in MEN1 than normal (P<0.0001 in all four limbs). Adrenal body was also significantly larger (P<0.05). Nodules were demonstrated in 17 (60%) of patients (versus 0.4-2% in the normal population). No statistically significant correlation was demonstrated between adrenal limb hyperplasia and abnormal cortisol dynamics.

CONCLUSIONS

In patients with MEN1, adrenal limb hyperplasia and adrenal nodules are significantly more common than in the normal population, a phenomenon not previously documented in a quantitative manner. There was no significant correlation between adrenal limb hyperplasia and abnormal cortisol dynamics.

Molecular variation in pigmentation genes contributing to coat colour in native Korean Hanwoo cattle

Pigmentation genes such as TYR (tyrosinase), TYRP1 (tyrosinase-related protein 1), DCT (previously TYRP2, or tyrosinase-related protein 2), ASIP (agouti) and MC1R (melanocortin receptor 1) play a major role in cattle coat colour. To understand the genotypic profile underlying coat colour in native Korean Hanwoo cattle and Angus black cattle, portions of the above-mentioned genes were amplified. Sequence analysis revealed variation in the TYRP1 (exon 5) and MC1R genes. Restriction enzyme analysis of these two genes could distinguish between different colours of Hanwoo cattle. Quantitative estimates of melanin and eumelanin in hair from three different-coloured Hanwoo phenotypes and Angus black showed significant differences at the breed and phenotypic levels. Finally, sequence variants in MC1R were associated with total melanin and eumelanin in breeds as well as in Hanwoo phenotypes.

Acute symptomatic seizures in CNS infection

To determine the frequency and aetiology of acute symptomatic seizures in central nervous system (CNS) infections and to assess the clinical factors predicting the occurrence of the seizures, we retrospectively reviewed the medical records of patients diagnosed with CNS infections from 2000 to 2005. One hundred and forty-seven patients were included in the study. The clinical variables between those with and without acute symptomatic seizures were compared. Of the 147 patients, 23% (34/147) had acute symptomatic seizures. A significant relation between clinical variables and the occurrence of acute symptomatic seizures was found: encephalitis as the aetiology of the CNS infection, Glasgow Coma Scale (GCS) < or =12, and neurological deficits. By multiple logistic regression analysis, age of onset >42 years, encephalitis, and GCS < or =12 were found to be independently significant clinical variables for predicting the occurrence of acute symptomatic seizures. Encephalitis and GCS < or =12 are significant clinical variables for predicting the occurrence of acute symptomatic seizures in CNS infection, suggesting that patients with a greater extent of parenchymal damage are more vulnerable to acute symptomatic seizures.

Small-sized liver graft does not increase the risk of hepatocellular carcinoma recurrence after living donor liver transplantation

PURPOSE

Following implantation into adult recipients, living donor liver grafts usually undergo liver regeneration. This regeneration process may provoke the growth of occult hepatocellular carcinoma (HCC) cells in the recipient body. To assess the risk of HCC recurrence, we analyzed the influence of graft-recipient weight ratio (GRWR).

METHODS

The 181 recipients with HCC within the University of California at San Francisco (UCSF) criteria were divided into four groups according to GRWR: low GRWR (<0.8; n = 30), mid GRWR (0.8-1.0; n = 65), high GRWR (>1.0; n = 64), and whole liver graft group (>1.5; n = 22).

RESULTS

There were no differences in overall patient survival (P = .105) and recurrence-free survival (P = .406) among these four groups. GRWR <0.8 was not a significant risk factor for HCC recurrence. Similar outcomes were obtained in HCC patients who met the Milan criteria (n = 170).

CONCLUSIONS

We think that small living donor liver graft and subsequent liver regeneration do not increase the risk of posttransplant HCC recurrence when HCC is within the Milan or UCSF criteria.

Suitable whole blood levels 2 hours after neoral in liver transplant patients: experiences at a single center

Whole blood levels 2 hours after Neoral (C2) administration were observed to correlate better with area under the curve (AUC(0-4)) than trough levels (C0), suggesting that C2 may be the best single time point predictor of Neoral absorption. Owing to concerns about drug toxicity due to excessive immunosuppression, C2 adjustments to target blood levels may represent an advance. The present study measured C2 and levels to determine which correlated more closely with AUC(0-4).

METHODS

Between August 2003 and July 2004, 40 adult liver transplantations were performed in our center. All patients received Neoral twice daily. They were maintained at a C0 level of about 200 ng/mL. C0 levels were measured daily. C2 levels were estimated on postoperative days 3, 5, 7, 14, and 28. AUC(0-4) performed on postoperative days 3, 7, and 28 was calculated using the trapezoidal rule.

RESULTS

The mean AUC(0-4), C0, C1, C2, C3, and C4 were 1100.3 +/- 484.8 ng/mL, 197.1 +/- 84.7 ng/mL, 240.7 +/- 166.2 ng/mL, 307.8 +/- 162.6 ng/mL, 302.8 +/- 138.9 ng/mL, and 300.3 +/- 142.8 ng/mL, respectively. C2 correlated with AUC(0-4) (R2 = 0.868: P < .05) better than C0 (R2 = 0.245: P < .05), C1 (R2 = 0.604: P < .05), or C4 (R2 = 0.583: P < .05).

CONCLUSIONS

Neoral dose monitoring according to a mean C2 range of 307.8 +/- 162.6 ng/mL correlated better with AUC(0-4). Further studies are required to determine suitable C2 levels in liver transplant patients.

Evaluation of the methods for pupil size estimation: on the perspective of autonomic activity

The purpose of This work is to find the optimal calculation method about pupil size to estimate an activity of autonomic nerve system. To evaluate its state, we have to calculate an accurate pupil size from the image of free-rotated and yawed eye for 5 minutes. But calculation of the pupil size from image takes a long time. So we suppose three methods which considered cost (time), accuracy and evaluate for each. 'Method' 1 is to calculate the vertical pupil diameter from images, 'method 2' is to calculate the pupil size from whole image (method 2-1; by binarization and method 2-2; by binarization with shape evaluation) and 'method 3', the most accurate method, is from three-dimensional transformation of pupil image. As a result, for seven subjects, each method is takes about 6, 44, 124, 311 minutes to evaluate five-minute images (300,000 pixels/frame, 30 frames/sec). Also, the result of correlation between the parameter Lf/Hf ratio of heart rate variability, commonly used method for estimate the state of autonomic nerve system, and it of pupil size variability is, for each case, 0.34, 0.2, 0.69, 0.69.

Refined Suture Techniques to Prevent Bleeding From Accidental Slippage of Vascular Clamps During Living Donor Hepatectomy

Accidental slippage of vascular clamps during living donor hepatectomy can induce brisk bleeding and even imperil the donor. After practicing more than 1000 cases of living donor hepatectomy, the investigators realized that specialized suture techniques were important to secure the vascular closure to prevent unnecessary bleeding. For secure division of intrahepatic vein branches, we devised a continuous penetration suture method in which the orders of procedures were changed to clamping-closure-cut sequence. For secure division of the main and accessory hepatic vein branches from the inferior vena cava, we applied stay sutures at each corner and midpoint of the hepatic vein stump so as not to permit its slippage. After application of these methods, we did not experience any episode of accidental clamp slippage. We are sure that these suture techniques are beneficial to prevent unnecessary bleeding during living donor hepatectomy and to make surgeons feel at ease during the living donor operation.

A case report of split liver transplantation for two adult recipients in Korea

We report a case of split liver transplantation (SLT) for two adult recipients, which was the first successful case in Korea. The brain-dead donor was a 22-year-old man weighing 65 kg, but his liver volume was estimated as 2120 mL on computed tomographic volumetry. As it seemed to be too large for a 60-kg recipient candidate, SLT was planned after assessment of lobar liver volume and middle hepatic vein anatomy. The right lobe was mobilized first and the liver parenchyma transected along the right border of the middle hepatic vein. The 1240-g right lobe (segments 5 to 8) graft was implanted into a 57-year-old male patient with acute-on-chronic liver failure in the same manner as a living-donor graft. After that, routine procedures of cadaveric multiorgan procurement were performed. The 670-g left lobe (segments 1 to 4) with a retrohepatic vena cava, common bile duct, and aortic patch was implanted into another 37-year-old male recipient. These two recipients recovered uneventfully surviving 12 months to date. We integrated the surgical techniques learned from hundreds of adult-to-adult living donor liver transplants into this first trial of two adult SLT.

Intraoperative assessment of hepatic venous congestion with direct clamping of the hepatic vein trunk for living donor liver transplantation

We devised a hepatic vein clamping method to assess the amount of hepatic venous congestion (HVC) before liver transection. From February 2003 to May 2003, this method was applied to 5 of 58 living donor livers especially to assess donor safety. The left portal vein and proper hepatic artery as well as the middle hepatic vein (MHV)-left hepatic vein (LHV) trunk were clamped simultaneously to assess the HVC in the remnant right lobe before performing extended left lobectomy. As three donors demonstrated the extent of the HVC equivalent to about 40% of the right lobe volume (RLV), their operations proceeded according to the preoperative plan. The territory of HVC after liver transection was the same as that observed with direct clamping of the hepatic vein. However, one donor showed massive HVC more than 50% of RLV and the operative plan was adjusted to harvest only the left lobe without the MHV trunk for donor safety. To assess the HVC in the remnant left lobe, the isolated LHV trunk was occluded after clamping the donor's proper hepatic artery. The whole left lobe except for a small area at the anterior portion of the medial segment became discolored on LHV clamping: the opposite demarcation appeared on MHV clamping. The amount of HVC was so small that we harvested the right lobe with the MHV trunk. All donors and recipients recovered uneventfully. We believe that this direct clamping method makes the assessment of HVC feasible before parenchymal transection of a donor liver.

Novel method for cell immobilization and its application for production of oligosaccharides from sucrose

AIMS

The purpose of the present investigation was to develop a novel method for cell immobilization.

METHODS AND RESULTS

Aureobasidium pullulans cells were mixed with an alginate solution, and the mixture was extruded to form small gel beads as hydrated-immobilized cells. The beads were then placed at -15 degrees C for 6-24 h to induce freeze-dehydration. The freeze-dehydration resulted in shrinkage of beads as a result of water removal reducing bead volume by 82% and bead weight by 85%. The dehydrated beads were successfully used for the production of fructo-oligosaccharides in a model reactor system.

CONCLUSIONS

Dehydrated beads may provide some commercial advantages over conventional immobilized cells.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study shows that bioreactor performance can be improved up to two times by the use of the dehydrated beads.

Kuwanon G: an antibacterial agent from the root bark of Morus alba against oral pathogens

Kuwanon G was isolated from the ethyl acetate fraction of methanol extract of Morus alba and its structure was elucidated by 13C-NMR, 1H-NMR and FAB-MS. Antibacterial activity of kuwanon G was investigated by the minimum inhibitory concentration (MIC) test and the viable cell count method. MIC of kuwanon G against Streptococcus mutans causing dental caries was determined to be 8.0 microg/ml. The bactericidal test showed that kuwanon G completely inactivated S. mutans at the concentration 20 microg/ml in 1 min. Kuwanon G also significantly inhibited the growth of other cariogenic bacteria such as Streptococcus sobrinus and Streptococcus sanguis, and Porpyromonas gingivalis causing periodontitis. Transmission electron microscopy (TEM) of kuwanon G treated cells demonstrated remarkable morphological damage of the cell wall and condensation of the cytoplasm.

Adult-to-adult living donor liver transplantation at the Asan Medical Center, Korea

Between February 1997 and December 2001, 311 adult-to-adult living donor liver transplants (A-A LDLTs) were performed at the Asan Medical Center for patients above 20 years of age. Indications for A-A LDLT were: chronic hepatitis B (203), chronic hepatitis C (5), hepatocellular carcinoma (64), alcoholic cirrhosis (9), cryptogenic cirrhosis (4), secondary biliary cirrhosis (5), primary biliary cirrhosis (1), Wilson' s disease (2), autoimmune hepatitis (1), hepatic tuberculosis (1), cholangiocarcinoma (1), fulminant hepatic failure (14) and primary non-function of cadaveric liver graft (1). Of 311 A-A LDLTs, 36 were of medical high urgency, 20 were for acute and subacute hepatic failure, 15 were for hepato-renal syndrome and 1 was for primary non-function. Recipient age ranged from 27 to 64 years. Donor age ranged from 16 to 62 years. There was no donor mortality. Implanted liver grafts were categorized into seven types: 175 modified right lobe (MRL), 70 left lobe, 32 right lobe, 20 dual grafts, 10 left lobe plus caudate lobe, three extended right lobe and one posterior segment. In MRL, the tributaries of the middle hepatic vein were reconstructed by interpositioning a vein graft. Indication for dual graft implantation was the same as single graft A-A LDLT, and four of 20 were emergency cases. Of 20 dual grafts, 14 received two left lobes, four received a left lobe and a lateral segment, one received a right lobe and a left lobe and one received a lateral segment and a posterior segment. Graft volume ranged from 28% to 83% of the standard liver volume of the recipients. There were 33 (10.6%) in-hospital mortalities (< 4 months) among the 310 patients after 311 A-A LDLTs. Of the 36 patients receiving emergency transplants, 31 survived. These encouraging results justify the expansion of A-A LDLT in coping with increasing demands, even in urgent situations. We have aimed to introduce the establishment of the efficacy of A-A LDLT in various end-stage chronic and acute liver diseases, as well as new technical advances to overcome small graft-size syndrome by using dual-graft implantation and MRL, both of which were first developed in our department.

Self-assembly of one-dimensional coordination polymers from AgX (X = CF(3)SO(3)(-), ClO(4)(-), and NO(3)(-)) and 2-aminomethylpyridinedipropionitrile (2-AMPDPN)

Three novel supramolecules whose topologies depend on the counteranion, [Ag(2-AMPDPN)X] (X = CF(3)SO(3)(-) (1), ClO(4)(-) (2), and NO(3)(-) (3)), have been prepared by the self-assembly of AgX (X = CF(3)SO(3)(-), ClO(4)(-), and NO(3)(-)) with 2-aminomethylpyridinedipropionitrile (2-AMPDPN). The crystal structures reveal different packing arrangements of the one-dimensional infinite coordination polymers. Compound 1 is made up of ladder chains that are interlocked by cyano groups, while the polymeric chain of 2 is isomorphous to 1 except for the Ag-Ag interaction. Compound 3 consists of helical chains that are surrounded by nitrate. The adjacent helical chains are racemic. The structures of 1, 2, and 3 suggest the role that the counterions may play in the network construction.