• Title/Summary/Keyword: termination

Search Result 1,180, Processing Time 0.04 seconds

The Effect of Organic solvents on Interrupting Diapause Initiation in Prospective Diapause Eggs of Bombyx mori. (가잠란의 휴면개시조지에 관한 유기용매의 효과)

  • 김삼은
    • Journal of Sericultural and Entomological Science
    • /
    • v.27 no.1
    • /
    • pp.24-30
    • /
    • 1985
  • The effect of some organic solvents on interrupting diapause of Bombyx mori eggs was examined to provide a clue to the mechanism of diapause initiation. Methyl alcohol and benzene proved to be efficient in developing the prospective diapause eggs upto the stage of hatching or body pigmentation of the embryos. On the other hand, most of the eggs soaked in chloroform and mixture solution of chloroform-methyl alcohol (2:1) died in the early embryonic developmental stage with yellow or red brown colours, and the egg weights decreased upto ca. 40% of the original weight 8 days after the treatments. Methyl alcohol treatment for 2, 5 and 10 min to the 5hr-old-eggs led to empergence of the larvae, with high incidence (70∼80%) in the race of Kumchu X Chonghwa and with low indidence (1∼4%) in Daezo. The effect of same treatment to 20hr old eggs decreased to ca. 10% in the emergence of larvae in Kumchn X Chonghwa and increased to 20∼30% in Daezo, while the effect disappeared shortly after the diapause initiation (48hr-old-eggs). Considering the high dependency upon the egg age of the sensitivity to solvents, it was supposed that initiation and termination of diapause may be controlled by different mechanism. It was also suspected that the solvents exert their effect on the permeability of the eggshell.

  • PDF

Single Extrahepatic Portosystemic Shunt in 3 Dogs: CT Findings and Progress (3마리의 개에서 발생한 단일 간외성 문맥전신 단락 증례)

  • Lee, Hee-Chun;Ji, Chang-Moo;Moon, Jong-Hyun;Cho, Kyu-Woan;Kim, Young-Ki;Kang, Byeong-Teck;Jung, Dong-In
    • Journal of Veterinary Clinics
    • /
    • v.29 no.6
    • /
    • pp.488-493
    • /
    • 2012
  • Two Maltese (2-year-old, intact female and 4-month-old, intact female) and a Pekingese (10-year-old, intact male) dogs were referred due to vomiting, anorexia, head-pressing and hypersalivation. Physical examinations, complete blood count, serum chemical analysis, radiography, ultrasonography and computed tomography (CT) were evaluated. Laboratory findings in these dogs included high hepatic enzyme, serum bile acid and ammonia concentration. Microhepatia was found on abdominal radiographs in two dogs. The existence of portosystemic shunt was presented in abdominal ultrasonography. The shunt vessel was identified in all dogs by CT imaging. Based on three-dimensional CT reconstruction, the origin and termination of each shunt vessel were defined certainly. In consequence, each dog was diagnosed single extrahepatic portosystemic shunt. After diagnosis, surgical treatment was performed in all dogs. This case report describes clinical finding, imaging characteristics, and three-dimensional CT imaging of single extrahepatic portosystemic shunt cases.

An experimental study on the biological safety and compatability of P.V.C. made in Korea (한국산 P.V.C.의 생물학적 안정도 및 적합성에 대한 실험적 고찰)

  • Sun, Kyung
    • Journal of Chest Surgery
    • /
    • v.17 no.1
    • /
    • pp.157-166
    • /
    • 1984
  • These biologic test procedures are designed to test the suitability of P.V.C. made in Korea intended for parenteral preparation, which were based on the U.S. Pharmacopeia XIX "Biologic Test-Plastic Container", Official from July 1, 1975. Healthy adult human blood and rabbits weighing 2\ulcorner.2Kg were used for test materials. Sample P.V.C. were sampled from the medical equipments made in Korea randomly and Control P.V.C. were sampled from the standardized Cobe and Polystan P.V.C. tubes. P.V.C. extract was prepared from a homogeneous P.V.C. samples by incubating 60 square centimeters of the sample per 20 millimeters of sterile pyrogen-free saline at 70\ulcorner for 72 hours or autoclaving at 120\ulcorner for 1 hour. The Implantation Test was designed to evaluate the reaction of living tissue to the plastic by the method of the implantation of the Sample itself into animal tissue. The Systemic Injection Test, the Intracutaneous Test, and the remainders were designed to determine the biological response of animals to plastics by the single-dose injection of specific extracts prepared from a Sample. The results are as follows; 1.Implantation Test - No significant difference for reactions was noted between the Sample treated animal and the Control after 72 hours of implantation. 2.Systemic Toxicity Injection Test - No sign of toxicity and/or death immediately after injection and at 4, 24, 48 hours respectfully after injection. 3.Intracutaneous Test - None of the animals treated with the Sample showed a significantly greater reaction than the observed in the animals treated with Blank. 4.Pyrogen Assay-Only one animal treated with the Sample showed the maximal rise of rectal temperature about 0.2\ulcorner after 3 hours of injection, but remainders showed no change. 5.Hemolytic Index - The positive Control tube of distilled water exhibited complete hemolysis while the negative Control tube and P.V.C. extract were negative demonstrating no hemolysis. 6.Cell Morphology of Erythrocytes and Leukocytes on Stored, Heparinized Human Blood -- There was no significant difference in the morphology of either the Control or Sample extract. 7.Clotting Mechanism of Human Blood in vitro - After allowing to the P.V.C. extract at room temperature for 5 Hours and at 10\ulcorner for 24 hours, there was no appreciable difference in Prothrombin Time under these conditions. 8.Clotting Mechanism of Rabbit in vivo - At the termination of 5 days after intraperitoneal injection of the P.V.C. extract, no significant changes in Clotting Time were observed. According to the above results, it could be concluded that the P.V.C. made in Korea was acceptable for parenteral preparation, especially treated with physiologic saline and/or human blood.man blood.

  • PDF

Characterization, Cloning and Expression of the Ferritin Gene from the Korean Polychaete, Periserrula leucophryna

  • Jeong Byeong Ryong;Chung Su-Mi;Baek Nam Joo;Koo Kwang Bon;Baik Hyung Suk;Joo Han-Seung;Chang Chung-Soon;Choi Jang Won
    • Journal of Microbiology
    • /
    • v.44 no.1
    • /
    • pp.54-63
    • /
    • 2006
  • Ferritin is a major eukaryotic protein and in humans is the protein of iron storage. A partial gene fragment of ferritin (255 bp) taken from the total RNA of Periserrula leucophryna, was amplified by RT-PCR using oligonucleotide primers designed from the conserved metal binding domain of eukaryotic ferritin and confirmed by DNA sequencing. Using the $^{32}P-labeled$ partial ferritin cDNA fragment, 28 different clones were obtained by the screening of the P. leucophryna cDNA library prepared in the Uni-ZAP XR vector, sequenced and characterized. The longest clone was named the PLF (Periserrula leucophryna ferritin) gene and the nucleotide and amino acid sequences of this novel gene were deposited in the GenBank databases with accession numbers DQ207752 and ABA55730, respectively. The entire cDNA of PLF clone was 1109 bp (CDS: 129-653), including a coding nucleotide sequence of 525 bp, a 5' -untranslated region of 128 bp, and a 3'-noncoding region of 456 bp. The 5'-UTR contains a putative iron responsive element (IRE) sequence. Ferritin has an open reading frame encoding a polypeptide of 174 amino acids including a hydrophobic signal peptide of 17 amino acids. The predicted molecular weights of the immature and mature ferritin were calculated to be 20.3 kDa and 18.2 kDa, respectively. The region encoding the mature ferritin was subcloned into the pT7-7 expression vector after PCR amplification using the designed primers and included the initiation and termination codons; the recombinant clones were expressed in E. coli BL21(DE3) or E. coli BL21(DE3)pLysE. SDS-PAGE and western blot analysis showed that a ferritin of approximately 18 kDa (mature form) was produced and that by iron staining in native PAGE, it is likely that the recombinant ferritin is correctly folded and assembled into a homopolymer composed of a single subunit.

Genenation of structural diversity in polyketides by combinatorial biosynthesis of polyketides: Part I. Generation of multiple bioactive macrolides by hybrid modular polyketide synthases in Streptomyces venezuelae, Part II. Production of novel rifamycins by combinatorial biosynthesis

  • Yoon, Yeo-Joon
    • Proceedings of the Korean Society for Applied Microbiology Conference
    • /
    • 2002.10a
    • /
    • pp.18-25
    • /
    • 2002
  • The pikromycin biosynthetic system in Streptomyces venezuleae is unique for its ability to produce two groups of antibiotics that include the 12-membered ring macrolides methymycin and neomethymycin, and the 14-membered ring macrolides narbomycin and pikromycin. The metabolic pathway also contains two post polyketide-modification enzymes, a glycosyltransferase and P450 hydroxylase that have unusually broad substrate specificities. In order to explore further the substrate flexibility of these enzymes a series of hybrid polyketide synthases were constructed and their metabolic products characterized. The plasmid-based replacement of the multifunctional protein subunits of the pikromycin PKS in S. venezuelae by the corresponding subunits from heterologous modular PKSs resulted in recombinant strains that produce both 12- and 14-membered ring macrolactones with predicted structural alterations. In all cases, novel macrolactones were produced and further modified by the DesVII glycosyltransferase and PikC hydroxylase leading to biologically active macrolide structures. These results demonstrate that hybrid PKSs in S. venezuelae can produce a multiplicity of new macrolactones that are modified further by the highly flexible DesVII glycosyltransferase and PikC hydroxylase tailoring enzymes. This work demonstrates the unique capacity of the S. venezuelae pikromycin pathway to expand the toolbox of combinatorial biosynthesis and to accelerate the creation of novel biologically active natural products. The polyketide backbone of rifamycin B is assembled through successive condensation and ${\beta}$-carbonyl processing of the extender units by the modular rifamycin PKS. The eighth module, in the RifD protein, contains nonfunctional DH domain and functional KR domain, which specify the reduction of the ${\beta}$-carbonyl group resulting in the C-21 bydroxyl of rifamycin B. A four amino acid substitution and one amino acid deletion were introduced in the putative NADPH binding motif in the proposed KR domain encoded by rifD. This strategy of mutation was based on the amino acid sequences of the corresponding motif of the KR domain of module 3 in the RifA protein, which is believed dysfunctional, so as to introduce a minimum alteration and retain the reading frame intact, yet ensure loss of function. The resulting strain produces linear polyketides, from tetraketide to octaketide, which are also produced by a rifD disrupted mutant as a consequence of premature termination of polyketide assembly. Much of the structural diversity within the polyketide superfamily of natural products is due to the ability of PKSs to vary the reduction level of every other alternate carbon atom in the backbone. Thus, the ability to introduce heterologous reductive segments such as ketoreductase (KR), dehydratase (DH), and enoylreductase (ER) into modules that naturally lack these activities would increase the power of the combinatorial biosynthetic toolbox. The dehydratase domain of module 7 of the rifamycin PKS, which is predicted to be nonfunctional in view of the sequence of the apparent active site, was replaced with its functional homolog from module 7 of rapamycin-producing polyketide synthase. The resulting mutant strain behaved like a rifC disrupted mutant, i.e., it accumulated the heptaketide intermediate and its precursors. This result points out a major difficulty we have encountered with all the Amycolatopsis mediterranei strain containing hybrid polyketide synthases: all the engineered strains prepared so far accumulate a plethora of products derived from the polyketide chain assembly intermediates as major products instead of just analogs of rifamycin B or its ansamycin precursors.

  • PDF

Effects of electroacupuncture on the expression of iNOS in Nuclei of solitary tract and Rostral ventrolateral medulla in spontaneously hypertensive rats (전침자극이 자연 발증 고혈압 흰쥐의 혈압 조절 중추에서 iNOS의 발현에 미치는 영향)

  • Hwang, Hye-Suk;Kim, Yu-Sung;Lee, Ji-Eun;Han, Kyung-Ju;Choi, Sun-Mi;Koo, Sung-Tae
    • Korean Journal of Oriental Medicine
    • /
    • v.12 no.3 s.18
    • /
    • pp.59-67
    • /
    • 2006
  • Aims: Acupuncture has been used for the treatment of essential hypertension, but the efficacy and the mechanism of acupuncture in prevention of hypertension are still unclear. We tested the hypothesis that electroacupuncture (EA) applied to Baekhoe (GV20) changes NO/NOS system during development of hypertension in spontaneously hypertensive rats (SHR), and thereby causes the delay of development of hypertension in SHR. Methods: The male SHR rats in the developmental stages of hypertension (7-8 weeks) were randomly divided into three groups (control group, GV20 acupuncture group, and tail acupuncture group). And the age matched Wistar Koyto Rats (WKY) were randomly divided into two groups (nagative control, GV20 acupuncture group). EA treatments (10Hz, 1mA, 0.1ms) were carried out for 25 min/day for five consecutive days. The systolic blood pressure (SBP) was determined in conscious rats by the tail-cuff method using automatic BP mornitoring system. We investigated the activations of inducible NO synthase (iNOS) in nuclei of solitary tract (NTS) and rostral ventrolateral medulla (RVLM) of SHR by the western blotting method. Results: The SBP after the termination of EA stimulation applied to the GV20 was stabilized at $169.14{\pm}3.67$ mmHg which is lower value than that of the control group. The SBP of control group was elevated to $178.14{\pm}3.49$ mmHg. In addition, we evaluated NOS activity as well as iNOS protein expression of NTS and RVLM in both of SHR and WKY. The iNOS activity in NTS was significantly higher in SHR than in WKY. Furthermore, the iNOS activity of NTS showed significant decreases in EA groups compare to that of non treated SHR group. Although iNOS expression of RVLM showed non significant changes between SHR and WKY, EA significantly enhanced the iNOS expression in SHR. Our data support the hypothesis that delayed development of hypertension and altered iNOS expression of NTS and RVLM by EA stimulations in SHR rats. Conclusions: The findings demonstrate that acupuncture can change NO/NOS system in NTS and RVLM, and exert beneficial role on development of hypertension.

  • PDF

A Single Nucleotide Deletion resulting in Frameshift in Two Korean Neonates with Thyroxine-Binding Globulin Deficiency (단일 뉴클레오타이드 결손으로 인한 Frameshift 돌연변이로 규명된 티록신결합글로불린 결핍증 1례)

  • Park, Sang-Joon;Suh, Jin-Soon;Jung, Min-Ho;Lee, Hee-Jin;Suh, Byung-Kyu;Lee, Won-Bae;Lee, Byung-Churl
    • Clinical and Experimental Pediatrics
    • /
    • v.48 no.11
    • /
    • pp.1252-1255
    • /
    • 2005
  • Abnormalities in the levels of thyroxine-binding globulin (TBG) are not associated with clinical disease and they do not require treatment. Congenital TBG deficiency is inherited in an X-linked manner. To date, some complete and partial TBG variants and one polymorphism have been identified by analysis of the TBG gene. Two male neonates were referred to us because of their low $T_4$ levels that were noted on the neonatal screening test. They showed normal levels of free $T_4$ and TSH. Their serum TBG was not detectable and those values of their parents were within the normal ranges. The genomic DNA was extracted from their white blood cells and the four coding exons of the TBG gene were amplified by using polymerase chain reaction. Sequencing of the four coding regions and all the intron/exon junctions revealed a single nucleotide deletion of the first base of the codon 352 of the mature protein in both of the neonates. This mutation resulted in a frameshift and a premature stop codon (TGA) 374. Their mothers were shown to be heterozygotes. We detected a single nucleotide deletion resulting in a frameshift in two male Korean neonates who had complete TBG deficiency.

A Study on Trends for Reforming the Rule of Warranty in English Insurance Contract Law (영국 보험계약법 상 담보법원칙의 개혁동향에 관한 연구)

  • Shin, Gun-Hoon
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
    • /
    • v.55
    • /
    • pp.209-240
    • /
    • 2012
  • Since the age of Lord Mansfield, who laid the foundation of the modern English insurance contract law in the second part of the 18th century, English insurance law has developed a unique rule of warranty. Lord Mansfield adopted very different approach and afforded such a strict legal character to insurance warranty, because the promise, given by the insured, played an important role for the insurer to assess the scope of the risk insured at that time. It is still important that the insured keep his promises strictly to the insurer under the insurance contract, but legal environments have changed dramatically since the times of Lord Mansfield. English Law Commission proposed some proposals for reforming the warranty regime to reflect the changes of legal environment in CP 2007. This article is, therefore, designed to examine the proposals and consider their legal and practical implications. The proposals of Law Commission is summarized as following. First, in CP 2007, Law Commission made two principal proposals for reform of the law on warranty. The first is that the insurer should not be entitled to rely on a breach of warranty unless the insured has been provided with a witten statement of what they have undertaken under warranty. The second is that the insurer should not be entitled to reject a claim on the ground that the insured has breached a warranty unless there was a causal connection between the breach and the loss. Secondly, for consumer insurance, the rule requiring a causal connection would be mandatory, whereas for business insurance, it would be possible for the parties to agree on the effect a breach of warranty should have, provided they use clear language to express their intentions. Thirdly, where the insured contracted on the insurer's written standard terms of business, some statutory controls would be afforded to the contract to ensure that the cover was not substantially different from what the insured reasonably expected. Finally, Law Commission propose that a breach of warranty give the insurer the right to terminate the contract, rather than automatically discharging it from liability, but (unless otherwise agreed) only if the breach has sufficiently serious consequences to justify termination under the general law of contract. Having evaluated the proposals of the Law Commission and considered their legal and practical implications, it is quite clear that the proposed rule interfere with freedom of contract and create legal uncertainty. But change can not made without any victims, so Law Commission's attempt to change severe and injust aspects of the warranty regime would be very welcomed and respected.

  • PDF

A Study of the Summary Trial System's Reform Measures (현행 즉결심판제도의 개선방안 연구)

  • Kwak, Young-Kil
    • Korean Security Journal
    • /
    • no.13
    • /
    • pp.47-70
    • /
    • 2007
  • The criminal procedure is based upon two ideal values, or 'speedy trial and economy of litigation' and 'finding truth and guarantee of human rights', which are conflicting each other. The so called summary trial system, a simplified procedure through which a judge handles clearly obvious and minor offences in a quick and efficient manner, has its essential purpose of termination lawsuits promptly and freeing suspects or defendants from criminal procedure at the earliest possible moment. But its excessive emphasis on this purport is very likely to result in insufficient examination and inadequate protection of suspects' or defendants' rights. Therefore, the summary trial system needs a variety of safeguards to prevent these feasible - but undesirable - effects. From this point of view, we should objectively review the current summary trial system. The main object of this study is to investigate what problems the system has both in institution and in practice, and to suggest legal measures, including the abolition of it, to improve the simplified procedure. In conclusion, the summary trial system should be maintained because it has still more merits than faults. And these defects will be able to be overcome by reform measures ; for example, the introduction of the right to opt between the summary procedure and the formal trial, the abolition of detention and so on.

  • PDF

Adenosine $^{99m}Tc-MIBI$ Scintigraphy in the Diagnosis of Coronary Artery Disease: Comparison with Exercise $^{99m}Tc-MIBI$ Scintigraphy (관상동맥 질환에서의 Adenosine 부하 $^{99m}Tc-MIBI$ 심근 스캔의 진단적 가치 : 운동 부하 $^{99m}Tc-MIBI$ 심근 스캔과의 비교)

  • Kang, Seung-Wan;Woo, Eon-Jo;Chae, Sung-Chull;Jun, Jae-Eun;Park, Wee-Hyun;Chung, Byung-Cheon;Choi, Chung-Il;Lee, Jae-Tae;Lee, Kyu-Bo
    • The Korean Journal of Nuclear Medicine
    • /
    • v.26 no.1
    • /
    • pp.72-81
    • /
    • 1992
  • Pharmacologic coronary vasodilation in conjunction with myocardial scintigraphy has become an accepted alternative to dynamic exercise testing for the diagnosis of coronary artery disease. Although dipyridamole has traditionally been used for this purpose, it causes frequent side effect, which at times can be life-threatening. Moreover, dipyridamole dose not elicit maximal coronary vasodilation in a substantial number of patients receiving the usual i.v. dose. Adenosine is an endogenously produced compound that has significant effects as a coronary vasodilator and rapid onset action and extremely short half-life (< 10 seconds). The diagnostic accuracy and safety profile of adenosine $^{99m}Tc-MIBI$ myocardial scintigraphy were evaluated and comparison with exercise $^{99m}Tc-MIBI$ was performed. Twenty-eight subjects underwent $^{99m}Tc-MIBI$ imaging after adenosine infusion and exercise $^{99m}Tc-MIBI$ imaging. Adenosine was infused intravenously at a dose of 0.14mg/kg/body weight per minute for 6 min and MIBI was injected at 3 minute. Adenosine caused an incerease in heart rate ($64{\pm}12$ at baseline versus $74{\pm}16$ beats/min at peak effect, p<0.001), a mild decrease in systolic and diastolic blood pressure and a slightly increase in PR interval(p; NS). Side effects were reported in 92% of patients and were mostly mild in nature and promptly resolved within 1 or 2 minutes of termination of adenosine infusion. Facial flushing (53%), chest pain (36%), mild dyspnea (39%), headache (21%), throat discomfort (21%) were frequent symptoms. ST segment depression (> 1 mm) and second degree AV block in electrocardiography occured in 11% of the patients, respectively. The overall sensitivity and specificity for individual coronary stenoses in 16 patients underwent coronary angiography were 88% and 95%, respectively. The agreement ratio of segmental perfusion between adenosine and exercise images was 92% (Kappa index=0.82). In conclusion, $^{99m}Tc-MIBI$ myocardial perfusion scintigraphy with intravenous adenosine is a feasible, safe and highly accurate noninvasive technique for the detection of coronary artery disease and results are at least comparable with those of exercise $^{99m}Tc-MIBI$ scintigraphy.

  • PDF