• The Korean Journal of Physiology and Pharmacology
• /
• 제20권2호
• /
• pp.185-192
• /
• 2016

Ampicillin, a ${\beta}$-lactam antibiotic, dose-dependently protects neurons against ischemic brain injury. The present study was performed to investigate the neuroprotective mechanism of ampicillin in a mouse model of transient global forebrain ischemia. Male C57BL/6 mice were anesthetized with halothane and subjected to bilateral common carotid artery occlusion for 40 min. Before transient forebrain ischemia, ampicillin (200 mg/kg, intraperitoneally [i.p.]) or penicillin G (6,000 U/kg or 20,000 U/kg, i.p.) was administered daily for 5 days. The pretreatment with ampicillin but not with penicillin G significantly attenuated neuronal damage in the hippocampal CA1 subfield. Mechanistically, the increased activity of matrix metalloproteinases (MMPs) following forebrain ischemia was also attenuated by ampicillin treatment. In addition, the ampicillin treatment reversed increased immunoreactivities to glial fibrillary acidic protein and isolectin B4, markers of astrocytes and microglia, respectively. Furthermore, the ampicillin treatment significantly increased the level of glutamate transporter-1, and dihydrokainic acid (DHK, 10 mg/kg, i.p.), an inhibitor of glutamate transporter-1 (GLT-1), reversed the neuroprotective effect of ampicillin. Taken together, these data indicate that ampicillin provides neuroprotection against ischemia-reperfusion brain injury, possibly through inducing the GLT-1 protein and inhibiting the activity of MMP in the mouse hippocampus.

• Molecular & Cellular Toxicology
• /
• 제3권3호
• /
• pp.165-171
• /
• 2007

Mitomycin C (MMC), an antitumor antibiotic isolated from Streptomyces caespitosus, is used in chemotherapy of gastric, bladder and colorectal cancer. MMC is activated in vivo to alkylate and crosslink DNA, via G-G interstrand bonds, thereby inhibiting DNA synthesis and transcription. This study investigates gene expression changes in response to MMC treatment in order to elucidate the mechanisms of MMC-induced toxicity. MMC was admistered with single dose (0.32 and 1.6 ${\mu}M$) to TK6 cells. Applied Biosystem's DNA chips were used for identifying the gene expression profile by MMC-induced toxicity. We identified up- or down-regulated 90 genes including cyclin M2, cyclin-dependent kinase inhibitor 1A (p21, cip1), programmed cell death 1, tumor necrosis factor (ligand) superfamily, member 9, et al. The regulated genes by MMC associated with the biological pathways apoptosis signaling pathway. Further characterization of these candidate markers related to the toxicity will be useful to understand the detailed mechanism of action of MMC.

• Clinical and Experimental Pediatrics
• /
• 제63권2호
• /
• pp.48-51
• /
• 2020

Background: The etiopathogenesis of late preterm (LPT) birth is undetermined. Placental histopathology, which reflects an adverse intrauterine environment and is reportedly associated with preterm labor and neonatal morbidities, has not been studied in LPT infants. Purpose: We investigated placental pathological lesion as markers of an adverse intrauterine environment during LPT labor. Methods: This retrospective case-control study compared placental histopathological and clinical variables between LPT and term neonates. Placental variables included chorioamnionitis, funisitis, hemorrhage, abruption, infarction, calcification, and syncytial knots. Maternal variables included age, substance abuse, pregnancyassociated diabetes mellitus and hypertension, duration of rupture of membrane, antibiotic use, and magnesium sulfate, whereas, those of neonates included gestational age, birth weight, race, sex, and Apgar scores. Standard statistical proedures were applied to analyze the data. Results: Chorioamnionitis (50% vs. 17.8%, P<0.001) and funisitis (20% vs. 4.4%, P=0.002) were more common in term infants. Placental infarction rate was insignificantly higher in LPT infants (25.6% vs. 14.3%, P=0.08). The mothers in the LPT group were older (30.4 years vs. 28.1 years, P=0.05; odds ratio [OR], 1.06; 95% confidence interval [CI], 0.998-1.12, P=0.056) and more often suffered from hypertension (28.9 vs. 12.9 %, P=0.02), and received magnesium sulfate (48.9 vs. 20%, P< 0.001; OR, 2.86; 95% CI, 1.12-7.29, P<0.05). Duration of rupture of membrane was higher in term infants (13.6 hours vs. 9.1 hours, P<0.001). Chorioamnionitis (OR, 0.33; 95% CI, 0.13-0.79; P<0.05) was associated with a lower risk of LPT delivery. Conclusion: Placental infection is not a risk factor for LPT births. There is a nonsignificant predominance of vascular anomalies in LPT placentas. Higher maternal age, magnesium sulfate therapy, and maternal hypertension are clinical risk factors for LPT labor.

• Clinical and Experimental Pediatrics
• /
• 제57권4호
• /
• pp.186-192
• /
• 2014

Purpose: The prevalence of macrolide-resistant Mycoplasma pneumoniae (MRMP) has increased worldwide. The aim of this study was to estimate the proportion of MRMP in a tertiary hospital in Korea, and to find potential laboratory markers that could be used to predict the efficacy of macrolides in children with MRMP pneumonia. Methods: A total of 95 patients with M. pneumoniae pneumonia were enrolled in this study. Detection of MRMP was based on the results of specific point mutations in domain V of the 23S rRNA gene. The medical records of these patients were reviewed retrospectively and the clinical course and laboratory data were compared. Results: The proportion of patients with MRMP was 51.6% and all MRMP isolates had the A2063G point mutation. The MRMP group had longer hospital stay and febrile period after initiation of macrolides. The levels of serum C-reactive protein (CRP) and interleukin-18 in nasopharyngeal aspirate were significantly higher in patients who did not respond to macrolide treatment. CRP was the only significant factor in predicting the efficacy of macrolides in patients with MRMP pneumonia. The area under the curve for CRP was 0.69 in receiver operating characteristic curve analysis, indicating reasonable discriminative power, and the optimal cutoff value was 40.7 mg/L. Conclusion: The proportion of patients with MRMP was high, suggesting that the prevalence of MRMP is rising rapidly in Korea. Serum CRP could be a useful marker for predicting the efficacy of macrolides and helping clinicians make better clinical decisions in children with MRMP pneumonia.

• 한국미생물·생명공학회지
• /
• 제13권2호
• /
• pp.163-167
• /
• 1985

유전물질이 쉽게 교환될 수 없는 세균의 유전학적 연구와 새로운 균주개발에 유용한 protoplast 융합을 Streptococcus lactis에 적용하기 위하여 UV를 사용하여 streptomycin (200$\mu\textrm{g}$/$m\ell$)과 refampicin(200 $\mu\textrm{g}$/$m\ell$)에 각각 내성을 나타내는 변이주를 분리하였으며 이 변이주들을 사용하여 Protoplast 융합의 영향인자를 검토하였다. 두 약제내성 변이주의 Protoplast를 1:1의 비율로 혼합하고 CaCl$_2$와 polyethylene glycol(PEG)로 처리하여 융합세포를 얻을 수 있었으며, 이 때 CaCl$_2$의 최적 처리농도는 150nM (최종농도 : 25mM)이었 고 40% (w/v)의 PEG 4,000으로 2분간 처리하는 것이 가장 좋았다. 융합빈도는 최대 6.26$\times$$10^{-5}$이었다. Mating에 의한 약제내성 유전자의 재조합 현상은 일어나지 않았다.

• Molecules and Cells
• /
• 제43권12호
• /
• pp.989-1001
• /
• 2020

Salmonella enterica serovar Typhimurium (S. Typhimurium) is a facultative intracellular pathogen that causes salmonellosis and mortality worldwide. S. Typhimurium infects macrophages and survives within phagosomes by avoiding the phagosome-lysosome fusion system. Phagosomes sequentially acquire different Rab GTPases during maturation and eventually fuse with acidic lysosomes. Lysophosphatidylcholine (LPC) is a bioactive lipid that is associated with the generation of chemoattractants and reactive oxygen species (ROS). In our previous study, LPC controlled the intracellular growth of Mycobacterium tuberculosis by promoting phagosome maturation. In this study, to verify whether LPC enhances phagosome maturation and regulates the intracellular growth of S. Typhimurium, macrophages were infected with S. Typhimurium. LPC decreased the intracellular bacterial burden, but it did not induce cytotoxicity in S. Typhimurium-infected cells. In addition, combined administration of LPC and antibiotic significantly reduced the bacterial burden in the spleen and the liver. The ratios of the colocalization of intracellular S. Typhimurium with phagosome maturation markers, such as early endosome antigen 1 (EEA1) and lysosome-associated membrane protein 1 (LAMP-1), were significantly increased in LPC-treated cells. The expression level of cleaved cathepsin D was rapidly increased in LPC-treated cells during S. Typhimurium infection. Treatment with LPC enhanced ROS production, but it did not affect nitric oxide production in S. Typhimurium-infected cells. LPC also rapidly triggered the phosphorylation of IκBα during S. Typhimurium infection. These results suggest that LPC can improve phagosome maturation via ROS-induced activation of NF-κB pathway and thus may be developed as a therapeutic agent to control S. Typhimurium growth.

• Journal of Veterinary Science
• /
• 제25권1호
• /
• pp.11.1-11.16
• /
• 2024

Background: Canine parvoviral enteritis (CPE) is a fatal disease worldwide. The treatment of CPE is based mainly on supportive and symptomatic treatment. Antiviral addition to the treatment may result in a higher survival. Objectives: This study evaluated the effects of antiviral treatments with a standardized treatment (ST) on the clinical and inflammatory response of dogs with naturally occurring CPE. Methods: Twenty-eight dogs with CPE caused by canine parvovirus type 2 were divided randomly into treatment groups. The ST group received fluid, antibiotic, antiemetic, and deworming treatments. The antiviral treatment groups received the same ST with an additional antiviral drug, recombinant feline interferon omega (rFeIFN-ω), oseltamivir (OSEL) or famciclovir (FAM). Results: Compared to the healthy control, the tumor necrosis factor-α, interleukin-1β, interferon (IFN)-α, IFN-γ, haptoglobin, and C-reactive protein values were high (p < 0.05) on day zero. At presentation, mild lymphopenia, neutropenia, and a high neutrophil to lymphocyte (LYM) ratio (NLR) were also observed. Adding rFeIFN-ω to the ST produced the best improvement in the clinical score with a decreased NLR, while leucocytes remained low and inflammatory markers stayed high on day three. The survival rates of the groups were 85.7% in ST+IFN, 71.4% in ST+OSEL, 71.4% in ST+FAM, and 57.1% in ST groups on day seven. Conclusions: Antiviral drugs may be valuable in treating CPE to improve the clinical signs and survival. In addition, the decrease in NLR in favor of LYM may be an indicator of the early prognosis before the improvement of leukocytes, cytokines, and acute phase proteins in CPE.

• 한국식품영양과학회지
• /
• 제39권10호
• /
• pp.1565-1572
• /
• 2010

본 총설에서는 동물실험에 이어 인체중재연구에서 양파의 유효성을 검증하고 단편적인 효능 검색 외에 활성물질의 분리, 동정 및 작용기작에 대한 구명연구를 위해 양파의 심혈관계 질환 및 항산화 효과에 대한 기존 중재연구를 종합하여 제시하고자 하였다. 양파의 심혈관계 질환 개선 효과는 대부분의 인체중재연구에서 혈중 콜레스테롤과 중성지방 저하 또는 혈소판 응집 저해 및 혈전 용해 활성 촉진 작용을 통해 입증되었다. 특히 이러한 유효성은 이미 혈중 지질 농도가 높아 혈액 유동성이 낮아진 대상자에게 약 300 g의 양파를 최소 12주 이상 제공할 때 효과적인 것으로 사료된다. 또한 공급되는 양파의 산지, 시료 제조 방법, 공급되는 시료양 및 기간과 중재 기간 동안 개인의 식사 조정과 같은 다양한 실험 조건의 차이가 결과에 영향을 준 것으로 사료되므로 이에 대한 엄격한 기준 및 관리가 필요할 것으로 보인다. 한편 양파는 LDL 산화 억제에는 직접적으로 작용하지 못하는 것으로 보이며 이는 쿼세틴이 단백질과 친화성이 높은 특성에서 기인된 것으로 사료된다. 그러나 양파의 항산화 효과를 전적으로 부인하기보다는 항산화 효과를 반영할 수 있는 보다 효과적인 분석 지표 선정 혹은 항산화 관련 유전자의 발현을 확인하는 등 새로운 분석 기술의 적용이 고려되어야 할 것으로 사료된다.

• 농약과학회지
• /
• 제14권2호
• /
• pp.148-156
• /
• 2010

마늘 저장병을 일으키는 푸른곰팡이병의 생물적 방제를 위하여 마늘 근면으로부터 부패억제효과가 우수한 Pantoea agglomerans S59-4(Pa59-4)를 선발하였다. 길항균 Pa59-4의 푸른곰팡이병에 대한 적정처리농도는 $10^7\sim10^8$ cfu/$m\ell$이었으며, Pa59-4의 처리효과는 병원균의 접종농도가 증가됨에 따라 감소되었다. 길항균 Pa59-4의 현탁액에 마늘을 침지 처리할 경우 저장 중 부패를 90%억제하였으며, 종구 분의 처리하여 파종하였을 때에도 무처리구 부패율이 86.7%인데 비해 Pa59-4 처리시 부패율이 23.1%로 부패를 현저히 감소시켰다. 마늘처리부위에서의 길항균의 밀도변동을 알아보기 위하여 항생제 마커로서 pimaricin과 vancomycin을 선발하였고 이들 항생제가 포함된 배지상에서 길항균 Pa59-4의 밀도변동을 저온조건과 상온조건으로 나누어 조사하였을 때 상처를 낸 마늘표면에서는 처리 후 30일까지도 밀도가 계속하여 증가하였으며, 저온 조건하에서는 처리 후 15일까지 증가하다가 그 이후에는 감소되는 것으로 나타났다. 길항균 Pa59-4의 산업화를 위하여 증량 제로 white carbon을 첨가하여 만든 미생물제제를 처리할 경우 저장 중 마늘부패를 40~50% 줄일 수 있었다. 이상의 결과로써 길항균 Pa59-4는 마늘저장 중 부패를 줄일 수 있는 유망한 길항균으로 판단되었다.

• Tuberculosis and Respiratory Diseases
• /
• 제66권5호
• /
• pp.358-364
• /
• 2009

연구배경: 폐렴의 치료는 해당 지역사회의 역학 자료, 항생제에 대한 감수성, 임상양상 등에 따라 적절한 항생제를 선택하는 것이 중요하다. 한반도 남단의 섬지역인 제주지역에서 이와 같은 연구가 시행된 바가 없다. 제주 지역에서 발생한 지역사회 획득 폐렴의 임상양상과 원인균을 전향적으로 조사하여, 향후 적절한 항생제를 선택할 수 있는 자료로 활용하고자 연구를 시행하였다. 방 법: 임상양상으로 지역사회획득폐렴을 진단 받은 환자를 대상으로 전향적으로 원인균 동정을 위해 객담 도말 및 배양검사, Streptococcus pneumoniae, Legionella 등 항원검사, Mycoplasma, Chlamydia 등에 대한 항체검사를 시행하였다. 진단 당시의 임상 양상, 검사실 자료, 초기 경험적 항생제 치료의 실패 여부 등을 분석하였다. 결 과: 203명(평균 64세)의 지역사회 획득 폐렴 환자로부터 10균주의 원인균(90명, 동정률 44.3%)이 동정되었다. 30명(33.3%)에서 두 개 이상의 세균이 동정된 다세균 감염이었다. S. pneumoniae, M. pneumoniae, C. pneumoniae, S. aureus, P. aeruginosa 등의 순으로 동정되었다. 초기 치료 실패로 항균제를 변경한 예가 약 1/4이었으며, 다세균 감염, 흉수, 높은 염증반응수치 등이 초기 치료실패의 위험요인이었다. 환자들로부터 분리된 30균주의 S. pneumoniae에서 penicillin (53.3%), macrolides (66.3%) 등에 대해 항생제 비감수성을 보였으며, levofloxacin과 ceftriaxone에 대해서는 항생제 감수성을 보였다. 결 론: 제주지역 지역사회획득 폐렴의 원인균은 S. pneumoniae이 가장 흔하고, M. pneumoniae, C. pneumoniae, S. aureus, 그람음성간균 등의 순이다. 초기 항생제 치료시 항생제 내성을 고려하여 약제를 선택해야 하며, 초기 치료 실패가 높은 임상양상에 주의를 요한다. 제주지역 지역사회획득 폐렴의 치료로 2-3세대 세팔로스포린 또는 호흡기계 퀴놀론 등을 초기 경험적 항생제로 추천한다.