• Fisheries and Aquatic Sciences
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• 제27권9호
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• pp.614-621
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• 2024

Channel catfish (Ictalurus punctatus), an introduced species in Vietnam, is widely cultured in the Northern provinces. The off-white grub disease in Channel catfish, caused by metacercariae of Dollfustrema bagarii (Digenea: Bucephalidae) lodged in internal organs, often results in heavy economic losses. Up to the present, there have been no specific guidelines for preventing and treating this disease. Here, we explore the potential treatment of infected channel catfish through the injection of Ivermectin. We evaluated the tolerance of channel catfish to the drug and determined the optimal dosage for treating off-white grubs disease. Healthy fish weighing 180-200 g received dosages of up to 3.250 mg/kg of body weight. The median lethal dose (LD₅₀) throughout a 24-hour period was 0.808 mg/kg body weight, with a confidence interval ranging from 0.583 to 1.118 mg/kg body weight. The infected fish used for treatment testing ranged in weight from 400 to 500 g. The value for the 24-hour median effective dose (ED₅₀) was 0.253 mg, and the appropriate therapeutic injection ranged from 0.300 to 0.700 mg per kg of body weight. Flowing the histopathological alterations, after the metacercariae were shriveled and died, the immune cells cleaned and eliminated them from fish.

• 미생물학회지
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• 제29권1호
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• pp.25-33
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• 1991

Antiviral activities of papaverine and nucleoside analogs, 9-[(1,3-dihydroxy-2-propoxy)methyl]guanine (DHPG) and acyclovir, against human cytomegalovirus (HCMV) infection were compared in vitro. Papaverine and DHPG were effective in reducing infectious HCMV yields with $ED_{50}{\s}$ (effective dose 50: the concentraion at which 50% of virus yields was obtained) of approximately 1.02 and $0.45{\mu}{\M}$, respectively; while acyclovir was less effective with an $ED_{50}$ of about $10.4{\mu}{\M}$The relative cytotoxicity of these drugs was evaluated under the same conditions used to measure infectious HCMV yields. Papaverine and DHPG demonstrated little cellular toxicity as measured by their effect on the viability of confluent cells at concentrations in the range of those demonstrating potent inhibition of HCMV replication. Similarly, protein synthesis was largely unaffected by these drugs in stationary mock-infected cells as measured by the incorporation of isotopically labelled amino acids. In contrast, cellular DNA synthesis was invariably reduced in the presence of either drug. HCMV-specific DNA synthesis was also strongly inhibited by papaverine and DHPG.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Current Trends in Toxicological Sciences
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• pp.115-115
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• 2002

The anti-diarrhea and spasmolytic activities of Soonkijangquebo (SKJQB), a Korean herbal anti-diarrhea formulation, were subjected to pharmacological evaluation. SKJQB, at a dose of 50\ulcorner200 mg/kg, inhibited castor oil-induced diarrhea in mice. The median effective dose (ED50) of the anti-diarrhea effect was 93 mg/kg.(omitted)

• Parasites, Hosts and Diseases
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• 제49권1호
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• pp.17-23
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• 2011

The aim of this study was to assess the cytotoxic effects of various concentrations of miltefosine on Leishmania major (MRHO/IR/75/ER) and L. tropica (MHOM/IR/02/Mash10) promastigotes and to observe the programmed cell death features. The colorimetric MTT assay was used to find L. major and L. tropica viability and the obtained results were expressed as 50% inhibitory concentration (IC50). Also, 50% effective doses (ED50) for L. major and L. tropica amastigotes were also determined, Annexin-V FLUOS staining was performed to study the cell death properties of miltefosine using FAGS analysis. Qualitative analysis of the total genomic DNA fragmentation was performed by agarose gel electrophoresis. Furthermore, to observe changes in cell morphology, promastigotes were examined using light microscopy. In both strains of L. major and L. tropica, miltefosine induced dose-dependent death with features of apoptosis, including cell shrinkage, DNA laddering, and externalization of phosphatidylserine. The IC50 was achieved at 22 ${\mu}M$ and 11 ${\mu}M$ for L. major and L. tropica after 48 hr of incubation, respectively. ED50 of L. major and L. tropica amastigotes were 5.7 ${\mu}M$ and 4.2 ${\mu}M$, respectively. Our results indicate that miltefosine induces apoptosis of the causative agent of cutaneous leishmaniasis in a dose-dependent manner. Interestingly, L. major did not display any apoptotic changes when it was exposed to miltefosine in concentrations sufficient to kill L. tropica.

• 대한화학회지
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• 제42권4호
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• pp.378-382
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• 1998

Phenylcyclohexylamine과 dexoxadrol에 대한 정량적 구조-작용 상관관계에 관한 계산을 반경험적 분자궤도법인 PM3와 Hyper Chem 프로그램을 이용하여 수행하였다. 19개의 PCA 유도체들의 프론티어 오비탈 크기와 LogP 값은 운동에 영향을 미치는 독성과 MES 발작 실험에서 $MES\;ED_{50}$과 $TD_{50}$을 예측하는 좋은 매개 변수라는 사실을 알았다.

• 한국토양비료학회지
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• 제45권6호
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• pp.1114-1119
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• 2012

$Ag^+$ 이온을 주성분으로 하는 $Ag^+N$과 $Ag^0$ 나노입자를 주성분으로 하는 $Ag^0NP$의 미생물학적 독성을 Microtox 생물검정법을 이용하여 수용액과 토양에서 용량-반응관계를 이용하여 비교, 평가하였다. 수용액 실험에서 Vibrio fisheri의 50% 발광 저해율을 보여주는 $EC_{50}$ 값은 $Ag^+N$이 $Ag^0NP$ 보다 현저히 낮게 나타나, 이온상태의 $Ag^+N$이 독성이 훨씬 높음을 알 수 있었다. 노출시간이 15분에서 30분으로 증가하면 독성 또한 증가했다. 반대로 토양 추출액 실험에서는 $Ag^+N$의 $ED_{50}$ 값이 $Ag^0NP$의 값 보다 높아, $Ag^+N$의 독성이 더 낮게 나타났다. 이것은 $Ag^+N$의 $Ag^+$가 토양 입자 또는 부식산에 강하게 흡착 되거나, Microtox 희석제 NaCl과 반응하여 난용해성 AgCl 침전물을 형성하여, 토양 추출액 중의 활성 Ag 농도가 감소한 것에 기인하는 것으로 판단되었다. Microtox 분석에 의한 Ag 나노용액의 생물학적 독성은 Ag의 존재형태 ($Ag^+$, $Ag^0$), 반응매질 (수용액, 토양), 노출시간에 따라 서로 상이한 결과를 보여 주었다.

• Applied Biological Chemistry
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• 제44권4호
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• pp.269-272
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• 2001

소나무속의 3수종, 소나무, 리기다소나무 및 잣나무의 부위별 추출물을 병원진균인 Colletotrichum gloeosporioides를 대상으로 항균활성을 조사하였다. 위 균주에 대하여 가장 우수한 항균활성은 잣나무 수피 및 근피 EtOAc 분획분에서 나타났는데 5.0 mg/l 농도에서 각각 98.8%와 100%로 조사되었다. 한편 두 분획분의 위 균주에 대한 $ED_{50}$(median effective dose)는 각각 469 ${\mu}g/ml$및 588 ${\mu}g/ml$로 조사되어 수피 추출물이 보다 낮은 값을 나타내었다. 잣나무 수피 EtOAc 분획분의 다른 병원진균 Alternaria brassicicola 및 Fusarium oxysporum에 대한 $ED_{50}$는 각각 533 ${\mu}g/ml$ 및 2,277 ${\mu}g/ml$로 나타나 이 분획분의 항균활성은 F. oxysporum보다 C. gloeosporiodes나 A. brassicicola이 더 우수한 것으로 조사되었다. 한편 잎 추출물의 경우를 보면, 소나무 잎 EtOAc 분획분은 C. gloeosporiodes에 대하여 5.0 mg/l 농도에서 39.6%의 활성을 보였으나 다른 두 수종의 잎 추출물에서는 추출 용액에 상관없이 거의 활성이 나타나지 않았다. 현재 주요 항균활성 화합물들은 분리, 동정 중에 있다.

• 대한임상독성학회지
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• 제14권1호
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• pp.9-15
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• 2016

Purpose: In most emergency department (ED), sedation is required before carrying out an invasive procedure on a pediatric patient. In the ED setting, it is essential to determine the optimal dose and administration route of CH for successful sedation. The aim of this study was to determine the optimal dose of CH for an invasive procedure and to examine the effectiveness of the drug's different administration routes. Furthermore, in this study, we performed simple survey using questionnaire which composed of Likert-scale to evaluate satisfaction of medical staffs in ED with administration routes. Methods: This study was conducted prospectively. The study participants were pediatric patients under 8 years old who visited the ED in two tertiary hospitals in South Korea within a period of 12 months. Results: Overall, 300 patients were included in this study. The age, sex, and weight of the patients were not shown to influence the sedation time. Chloral hydrate dosage is the independent factor to influence the both sedation and discharge time (p<0.01). In the comparison of the groups, groups 1, 2, and 5 showed no significant difference. On the other hand, groups 3 and 4 were shown to be statistically significantly different from group 1. Conclusion: Up to 100 mg/kg CH is safe to use in the emergency department for pediatric patients, but the initial dose of 50 mg/kg for oral administration should be considered in advance because it can provide safe and effective sedation with a lower possibility of causing an adverse effect.

• The Korean Journal of Pain
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• 제18권2호
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• pp.118-123
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• 2005

Background: A nerve ligation injury may produce a tactile allodynia. The effects of intrathecally delivered lamotrigine on allodynia induced due to fifth and sixth lumbar spinal nerves ligation in rats, using lumbar intrathecal catheters were examined. Methods: Sprague-Dawley rats (body weight 160-180 g) were prepared by tightly ligating the fifth and sixth left lumbar spinal nerves, with the implantation of a chronic intrathecal catheter for drug administration. Mechanical allodynia and allodynic threshold were measured using von Frey filaments and the updown method, respectively. After the baseline hind paw withdrawal thresholds had been obtained, lamotrigine (10, 30, 100 and $300{\mu}g$) was administered intrathecally. Thereafter, the dose-response curves and 50% effective dose ($ED_{50}$) were obtained. Motor dysfunction was assessed by observing the righting/stepping reflex responses and abnormal weight bearing. Results: Intrathecal administration of lamotrigine produced a dose-dependent antiallodynic action ($ED_{50}=61.7{\mu}g$). Mild motor weakness was observed with $300{\mu}g$ lamotrigine, but no severe motor impairment was found. Conclusions: It is suggested that intrathecal lamotrigine could produce moderate antagonism of mechanical allodynia at the spinal level in a rat neuropathic pain model with minimal motor weakness.

• The Korean Journal of Pain
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• 제25권1호
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• pp.1-6
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• 2012

Background: Curcumin has been reported to have anti-inflammatory, antioxidant, antiviral, antifungal, antitumor, and antinociceptive activity when administered systemically. We investigated the analgesic efficacy of intrathecal curcumin in a rat model of inflammatory pain. Methods: Male Sprague Dawley rats were prepared for intrathecal catheterization. Pain was evoked by injection of formalin solution (5%, $50{\mu}l$) into the hind paw. Curcumin doses of 62.5, 125, 250, and $500{\mu}g$were delivered through an intrathecal catheter to examine the flinching responses. The $ED_{50}$ values (half-maximal effective dose) with 95% confidence intervals of curcumin for both phases of the formalin test were calculated from the dose-response lines fitted by least-squares linear regression on a log scale. Results: In rats with intrathecal administration of curcumin, the flinching responses were significantly decreased in both phases. The slope of the regression line was significantly different from zero only in phase 2, and the $ED_{50}$ value (95% confidence interval) of curcumin was $511.4{\mu}g$ (23.5-1126.5). There was no apparent abnormal behavior following the administration of curcumin. Conclusions: Intrathecal administration of curcumin decreased inflammatory pain in rats, and further investigation to elucidate the precise mechanism of spinal action of curcumin is warranted.