200 research outputs found
Phenylalanine ammonia-lyase expression and pyranocoumarin accumulation in Angelica gigas plantlets exposed to light-emitting diodes
Angelica gigas (Dang Gui) is an important medicinal plant. In this study, we examined the accumulation of pyranocoumarin (decursin and decursinol angelate) and the expression of phenylalanine ammonia-lyase (PAL) in Korean angelica plantlet grown under different light-emitting diodes (LEDs) (red, orange, green, blue, and white). Three weeks after LED exposure (WAE), the transcript levels of phenylalanine ammonia-lyase mRNA in seedlings grown under orange LEDs were 4-, 18-, and 7-fold higher than those in seedlings grown under green, blue, and white LEDs, respectively. The decursinol angelate content was almost double than the decursin content. The highest levels of decursin (3.2 mg/g dry weight) and decursinol angelate (6 mg/g dry weight) were detected in plants grown under orange LEDs, at 2 WAE. Therefore, we suggest that orange LEDs may affect decursin and decursinol angelate accumulation. The findings of this study could help to determine an effective strategy for producing secondary metabolites in A. gigas using LED technology
DEL ์ ํ๊ตฌ์ ์ํ ํญ-D ๋์ข ๋ฉด์ญ
Extremely weak D variants called DEL are serologically detectable only by adsorption-elution techniques. A nucleotide change of exon 9 in RHD gene, RHD (K409K, 1227G>A) allelic variant is present in almost all the DEL individuals of East Asians. No DEL phenotype has yet been shown to induce a primary alloanti-D immunization in East Asia. A 68-yr-old D-negative Korean man was negative for anti-D at admission, and he developed alloanti-D after transfusion of red blood cells (RBC) from 4 apparently D-negative donors. Four donors who typed D-negative by routine serologic test were analyzed by real-time PCR for RHD gene and RHD (K409K). One donor was found to have RHD (K409K), This is the first case in which DEL RBCs with RHD (K409K) induced a primary alloanti-D immunization in Asian population. Because the DEL phenotype can induce an anti-D immunization in D-negative recipients, further discussion is needed whether RhD negative donors should be screened by molecular method and what an efficient genotyping method is for detecting the RHD gene carriers in Korea. (Korean J Lab Med 2009;29:361-5)Polin H, 2009, TRANSFUSION, V49, P676, DOI 10.1111/j.1537-2995.2008.02046.xFlegel WA, 2009, TRANSFUSION, V49, P465, DOI 10.1111/j.1537-2995.2008.01975.xSun CF, 2008, ANN CLIN LAB SCI, V38, P258Richard M, 2007, TRANSFUSION, V47, P852, DOI 10.1111/j.1537-2995.2007.01199.xLuettringhaus TA, 2006, TRANSFUSION, V46, P2128, DOI 10.1111/j.1537-2995.2006.01042.xYasuda H, 2005, TRANSFUSION, V45, P1581, DOI 10.1111/j.1537-2995.2005.00579.xWagner T, 2005, TRANSFUSION, V45, P520Gassner C, 2005, TRANSFUSION, V45, P527Kim JY, 2005, TRANSFUSION, V45, P345WAGNER FF, 2001, BMC GENET, V2, P10Avent ND, 2000, BLOOD, V95, P375Aubin JT, 1997, BRIT J HAEMATOL, V98, P356Okuda H, 1997, J CLIN INVEST, V100, P373Avent ND, 1997, BLOOD, V89, P2568HWANG YS, 1996, KOREAN J BLOOD TRANS, V7, P233DANIELS G, 1995, HUMAN BLOOD GROUPSMAK KH, 1993, TRANSFUSION, V33, P348LINCHU M, 1988, TRANSFUSION, V28, P350
Real-Time PCR Method for HPV DNA Detection
Human papillomavirus (HPV) infection is an important etiologic factor in cervical carcinogenesis. Various HPV DNA detection methods have been evaluated for clinicopathological level. For the specimens with normal cytological finding, discrepancies among the detection methods were frequently found and adequate interpretation can be difficult. 6,322 clinical specimens were submitted and evaluated for real-time PCR and Hybrid Capture 2 (HC2). 573 positive or "Not Detected but Amplified" (NDBA) specimens by real-time PCR were additionally tested using genetic analyzer. For the reliability of real-time PCR, 325 retests were performed. Optimal cut-off cycle threshold ( ) value was evaluated also. 78.7% of submitted specimens showed normal or nonspecific cytological finding. The distributions of HPV types by real-time PCR were not different between positive and NDBA cases. For positive cases by fragment analysis, concordance rates with real-time PCR and HC2 were 94.2% and 84.2%. In NDBA cases, fragment analysis and real-time PCR showed identical results in 77.0% and HC2 revealed 27.6% of concordance with fragment analysis. Optimal cut-off value was different for HPV types. NDBA results in real-time PCR should be regarded as equivocal, not negative. The adjustment of cut-off value for HPV types will be helpful for the appropriate result interpretation
Usefulness of Multiplex Real-Time PCR for Simultaneous Pathogen Detection and Resistance Profiling of Staphylococcal Bacteremia
Staphylococci are the leading cause of nosocomial blood stream infections. Fast and accurate identification of staphylococci and confirmation of their methicillin resistance are crucial for immediate treatment with effective antibiotics. A multiplex real-time PCR assay that targets mecA, femA specific for S. aureus, femA specific for S. epidermidis, 16S rRNA for universal bacteria, and 16S rRNA specific for staphylococci was developed and evaluated with 290 clinical blood culture samples containing Grampositive cocci in clusters (GPCC). For the 262 blood cultures identified to the species level with the MicroScan WalkAway system (Siemens Healthcare Diagnostics, USA), the direct real-time PCR assay of positive blood cultures showed very good agreement for the categorization of staphylococci into methicillin-resistant S. aureus (MRSA), methicillin-susceptible S. aureus (MSSA), methicillin-resistant S. epidermidis (MRSE), methicillin-susceptible S. epidermidis (MSSE), methicillin-resistant non-S. epidermidis CoNS (MRCoNS), and methicillin-susceptible non-S. epidermidis CoNS (MSCoNS) ( = 0.9313). The direct multiplex real-time PCR assay of positive blood cultures containing GPCC can provide essential information at the critical point of infection with a turnaround time of no more than 4 h. Further studies should evaluate the clinical outcome of using this rapid real-time PCR assay in glycopeptide antibiotic therapy in clinical settings
The Relationship between Lewis/Secretor Genotypes and Serum Carbohydrate Antigen 19-9 Levels in a Korean Population
Background : The Lewis histo-blood group system consists of 2 major antigens-Le(a) and Le(b)-and a sialyl Lewis antigen-carbohyd rate antigen (CA) 19-9. We investigated the distribution of Lewis genotypes and evaluated the relationship between the Lewis/Secretor genotypes and the serum level of CA 19-9 in a Korean population to identify whether the serum CA 19-9 levels are influenced by the Lewis/Secretor genotypes. Methods : The study included 242 individuals who had no malignancies. Lewis genotyping was performed for the 59T>G, 508G>A and 1067T>A polymorphic sites. The Secretor genotype was determined through analysis of the 357C>T and 385A>T polymorphic sites and the fusion gene. Serum CA 19-9 level was analyzed using an electrochemiluminescence immunoassay. Results : Individuals carrying the 3 common genotypes-Le/Le, Le/le(59,508), and Le/le(59,1067)-accounted for 95% of the study population. In the Korean population, the allelic frequencies of Le, Le(59)le(59,508) and le(59,1067) were 0.731, 0.010, 0.223, and 0.035, respectiveiy. We found a significant difference in serum CA 19-9 concentrations among the 9 LewislSecretor genotype groups (P<0.001). The serum CA 19-9 levels in subjects with genotype groups 1 and 2 (Le/- and se/se) were higher than those with genotype groups 3-6 (Le/- and Se/-; 15.63 vs 6.64 kU/L, P<0.001). Conclusions : Le/Le(59,508), and Le/le(59,1067) are frequent Lewis genotypes in Koreans. Because serum CA 19-9 levels are significantly influenced by the LewislSecretor genotypes, caution is suggested when interpreting the serum CA 19-9 levels. (Korean J Lab Med 2010;30:51-7)SONG SY, 2008, KOREAN J HEMATOL, V43, P34Park KU, 2005, ANN HEMATOL, V84, P656, DOI 10.1007/s00277-005-1041-5Hayashi N, 2004, PATHOBIOLOGY, V71, P26, DOI 10.1159/000072959Hamajima N, 2002, J MOL DIAGN, V4, P103HAMAJIMA N, 2002, GASTRIC CANCER, V5, P194Liu TC, 2000, ANN HEMATOL, V79, P599Lamerz R, 1999, ANN ONCOL, V10, P145Vestergaard EM, 1999, CLIN CHEM, V45, P54Liu YH, 1999, J HUM GENET, V44, P181Kim MJ, 2002, YONSEI MED J, V43, P427SHIBATA A, 2003, GASTRIC CANCER, V6, P8Liu YH, 1999, J FORENSIC SCI, V44, P82Liu YH, 1998, HUM GENET, V103, P204Pang H, 1998, HUM GENET, V102, P675Narimatsu H, 1998, CANCER RES, V58, P512Liu YH, 1996, J FORENSIC SCI, V41, P1018Koda Y, 1996, AM J HUM GENET, V59, P343Kudo T, 1996, J BIOL CHEM, V271, P9830ROUQUIER S, 1995, J BIOL CHEM, V270, P4632KELLY RJ, 1995, J BIOL CHEM, V270, P4640NISHIHARA S, 1994, J BIOL CHEM, V269, P29271MOLLICONE R, 1994, J BIOL CHEM, V269, P20987
Enhanced metabolic flux of methylerythritol phosphate (MEP) pathway by overexpression of Ginkgo biloba 1-Hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate Reductase 1 (GbHDR1) gene in poplar
Terpenoids are of great interests in a broad range of health-beneficial biological activities and various industrial applications. In plants, terpenoids are synthesized by two distinct pathways, methylerythritol phosphate (MEP) and mevalonate pathways in a separate location. MEP pathway supplies isoprene precursors isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP) of terpenoid biosynthesis in plant plastids. The MEP pathway has been an engineering target to increase the metabolic flux towards higher terpenoid production in plants. 1-Hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate reductase (HDR) is the terminal step of the MEP pathway to regulate the terpenoid biosynthesis and is encoded by three paralogous genes in Ginkgo biloba. In this study, we assessed the effect of overexpression of GbHDR1 on terpenoid metabolism in poplar plants. Overexpression of GbHDR1 in poplar plants accelerated growth and delayed winter-bud formation. Transcript levels of gibberellin, chlorophylls, and carotenoid biosynthetic genes in GbHDR1-overexpressing (GbHDR1ox) poplars were up-regulated, suggesting metabolic flux enhancement. Moreover, enhanced contents of chlorophylls and carotenoids in the leaves of the GbHDR1ox plants resulted in a higher photosynthetic rate as a consequence. Therefore, we expect the GbHDR1 overexpression will be a desirable engineering point of the MEP pathway for enhancing terpenoid metabolic flux and production in plants.This work was supported by the National Research Foundation of Korea (NRF) grant (2021R1A5A8029490); the Korea Foundation for Women In Science, Engineering and Technology (WISET) Returners into R&D Program grant; the intramural grant (2Z06670) from the Korea Institute of Science and Technology (KIST), Republic of Korea
Hemolytic Disease of the Newborn Associated with Anti-Jr(a) Alloimmunization in a Twin Pregnancy: The First Case Report in Korea
Jr(a) is a high-frequency antigen found in all ethnic groups. However, the clinical significance of the anti-Jr(a) antibody has remained controversial. Most studies have reported mild hemolytic disease of the newborn and fetus (HDNF) in Jr(a)-positive patients. Recently, fatal cases of HDNF have also been reported. We report the first case of HDNF caused by anti-Jr(a) alloimmunization in twins in Korea. A 33-yr-old nulliparous woman with no history of transfusion or amniocentesis was admitted at the 32nd week of gestation because of vaginal bleeding caused by placenta previa. Anti-Jr(a) antibodies were detected in a routine laboratory examination. An emergency cesarean section was performed at the 34th week of gestation, and 2 premature infant twins were delivered. Laboratory examination showed positive direct antiglobulin test and Jr(a+) phenotype in the red blood cells and the presence of anti-Jr(a) antibodies in the serum in both neonates. The infants underwent phototherapy for neonatal jaundice; this was followed by conservative management. They showed no further complications and were discharged on the 19th postpartum day. Preparative management to ensure the availability of Jr(a-) blood, via autologous donation, and close fetal monitoring must be performed even in cases of first pregnancy in Jr(a-) women. (Korean J Lab Med 2010;30:511-5)Arriaga F, 2009, TRANSFUSION, V49, P813, DOI 10.1111/j.1537-2995.2009.02118.xPeyrard T, 2008, TRANSFUSION, V48, P1906, DOI 10.1111/j.1537-2995.2008.01787.xROBACK JD, 2008, TECHNICAL MANUAL, P411CHUNG HJ, 2007, KOREAN J BLOOD TRANS, V18, P111Ishihara Y, 2006, FETAL DIAGN THER, V21, P269, DOI 10.1159/000091354Daniels GL, 2004, VOX SANG, V87, P304Kwon MY, 2004, TRANSFUSION, V44, P197Bellver-Pradas J, 2001, AM J OBSTET GYNECOL, V184, P75STROUP M, 1970, P 23 ANN M AM ASS BL, P86KIM DW, 1995, ELS APPL ELECT MAT, V6, P185MIYAZAKI T, 1994, VOX SANG, V66, P51OGASAWARA K, 1990, ACTA HAEMATOL JAPON, V53, P1131GARRATTY G, 1990, TRANSFUS MED REV, V4, P297NANCE SJ, 1987, TRANSFUSION, V27, P449BACON J, 1986, TRANSFUSION, V26, P543LEVENE C, 1986, TRANSFUSION, V26, P119TAKABAYASHI T, 1985, TOHOKU J EXP MED, V145, P97TOY P, 1981, VOX SANG, V41, P40ORRICK LR, 1980, AM J OBSTET GYNECOL, V137, P135NAKAJIMA H, 1978, VOX SANG, V35, P265VEDO M, 1978, TRANSFUSION, V18, P569TRITCHLER JE, 1977, TRANSFUSION, V17, P177KENDALL AG, 1976, TRANSFUSION, V16, P646
Can a routine follow-up blood culture be justified in Klebsiella pneumoniae bacteremia? a retrospective caseโcontrol study
Background : The need for mandatory confirmation of negative conversion in Klebsiella pneumoniae bacteremia (KpB) has not been adequately addressed. We conducted a retrospective caseโcontrol study of adult patients with KpB over a 5-year period in two tertiary-care hospitals to determine the risk factors for persistent bacteremia and to reevaluate the necessity of follow-up blood culture in KpB.
Methods : Persistent KpB is defined as the finding of K. pneumoniae in more than two separate blood-culture samples for longer than a two-day period in a single episode. The case- and control-groups were patients with persistent and non-persistent KpB, respectively, and they were matched 1-to-3 according to age and gender.
Results : Among 1068 KpB episodes analyzed after excluding polymicrobial infection and repeated KpB, follow-up blood cultures were performed in 862 cases (80.7%), 62 of which (7.2%) were persistent. Independent risk factors for persistence were intra-abdominal infection, higher Charlsons comorbidity weighted index score, prior solid organ transplantation, and unfavorable treatment response, which was defined as positivity for at least two parameters among fever, leukocytosis, and no decrease of C-reactive protein on the second day after initial culture. A proposed scoring system using four variables, namely, intra-abdominal infection, nosocomial KpB, fever and lack of C-reactive protein decrease, the last two being assessed on the second day after the initial blood culture, showed that only 4.9% of the patients with no risk factors or with only intra-abdominal infection had persistent KpB.
Conclusions : Though persistent KpB is uncommon, follow-up blood culture was performed in as many as 80% of the cases in this study. A more careful clinical assessment is warranted to reduce the cost and patient inconvenience involved in follow-up blood culture.Peer Reviewe
Toll-like receptor 2 downregulation and cytokine dysregulation predict mortality in patients with Staphylococcus aureus bacteremia
Background
Staphylococcus aureus bacteremia (SAB) presents heterogeneously, owing to the differences in underlying host conditions and immune responses. Although Toll-like receptor 2 (TLR2) is important in recognizing S. aureus, its function during S. aureus infection remains controversial. We aimed to examine the association of TLR2 expression and associated cytokine responses with clinical SAB outcomes.
Methods
Patients from a prospective SAB cohort at two tertiary-care medical centers were enrolled. Blood was sampled at several timepoints (โค5 d, 6โ9 d, 10โ13 d, 14โ19 d, andโโฅโ20 d) after SAB onset. TLR2 mRNA levels were determined via real-time PCR and serum tumor necrosis factor [TNF]-ฮฑ, interleukin [IL]-6, and IL-10 levels were analyzed with multiplex-high-sensitivity electrochemiluminescent ELISA.
Results
TLR2 levels varied among 59 SAB patients. On days 2โ5, TLR2 levels were significantly higher in SAB survivors than in healthy controls (pโ=โ0.040) and slightly but not significantly higher than non-survivors (pโ=โ0.120), and SAB patients dying within 7 d had lower TLR2 levels than survivors (Pโ=โ0.077) although statistically insignificant. IL-6 and IL-10 levels were significantly higher in non-survivors than in survivors on days 2โ5 post-bacteremia (Pโ=โ0.010 and Pโ=โ0.021, respectively), and those dying within 7 d of SAB (nโ=โ3) displayed significantly higher IL-10/TNF-ฮฑ ratios than the survivors did (Pโ=โ0.007).
Conclusion
TLR2 downregulation and IL-6 and IL-10 concentrations suggestive of immune dysregulation during early bacteremia may be associated with mortality from SAB. TLR2 expression levels and associated cytokine reactions during early-phase SAB may be potential prognostic factors in SAB, although larger studies are warranted.This study was supported by a research grant (13โ2014-002) from Seoul National University Bundang Hospital (Seongnam, South Korea). The funder had no role in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript
Genetic evidence of illegal trade in protected whales links Japan with the US and South Korea
We report on genetic identification of โwhale meatโ purchased in sushi restaurants in Los Angeles, CA (USA) in October 2009 and in Seoul, South Korea in June and September 2009. Phylogenetic analyses of mtDNA cytochrome b sequences confirmed that the products included three species of whale currently killed in the controversial scientific whaling programme of Japan, but which are protected from international trade: the fin, sei and Antarctic minke. The DNA profile of the fin whale sold in Seoul established a match to products purchased previously in Japan in September 2007, confirming unauthorized trade between these two countries. Following species identification, these products were handed over to the appropriate national or local authorities for further investigation. The illegal trade of products from protected species of whales, presumably taken under a national permit for scientific research, is a timely reminder of the need for independent, transparent and robust monitoring of any future whaling
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