• Journal of Microbiology and Biotechnology
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• 제25권3호
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• pp.366-374
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• 2015

Herein, we established a repeated-batch process for ethanol production from glycerol by immobilized Pachysolen tannophilus. The aim of this study was to develop a more practical and applicable ethanol production process for biofuel. In particular, using industrial-grade medium ingredients, the microaeration rate was optimized for maximization of the ethanol production, and the relevant metabolic parameters were then analyzed. The microaeration rate of 0.11 vvm, which is far lower than those occurring in a shaking flask culture, was found to be the optimal value for ethanol production from glycerol. In addition, it was found that, among those tested, Celite was a more appropriate carrier for the immobilization of P. tannophilus to induce production of ethanol from glycerol. Finally, through a repeated-batch culture, the ethanol yield (Y_e/g) of 0.126 ± 0.017 g-ethanol/g-glycerol (n = 4) was obtained, and this value was remarkably comparable with a previous report. In the future, it is expected that the results of this study will be applied for the development of a more practical and profitable long-term ethanol production process, thanks to the industrial-grade medium preparation, simple immobilization method, and easy repeated-batch operation.

• Journal of Korean Neurosurgical Society
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• 제59권3호
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• pp.259-268
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• 2016

Objective : Accumulation of advanced glycation end-products (AGE) and mitochondrial glycation is importantly implicated in the pathological changes of the brain associated with diabetic complications, Alzheimer disease, and aging. The present study was undertaken to determine whether sildenafil, a type 5 phosphodiesterase type (PDE-5) inhibitor, has beneficial effect on neuronal cells challenged with AGE-induced oxidative stress to preserve their mitochondrial functional integrity. Methods : HT-22 hippocampal neuronal cells were exposed to AGE and changes in the mitochondrial functional parameters were determined. Pretreatment of cells with sildenafil effectively ameliorated these AGE-induced deterioration of mitochondrial functional integrity. Results : AGE-treated cells lost their mitochondrial functional integrity which was estimated by their MTT reduction ability and intracellular ATP concentration. These cells exhibited stimulated generation of reactive oxygen species (ROS), disruption of mitochondrial membrane potential, induction of mitochondrial permeability transition, and release of the cytochrome C, activation of the caspase-3 accompanied by apoptosis. Western blot analyses and qRT-PCR demonstrated that sildenafil increased the expression level of the heme oxygenase-1 (HO-1). CoPP and bilirubin, an inducer of HO-1 and a metabolic product of HO-1, respectively, provided a similar protective effects. On the contrary, the HO-1 inhibitor ZnPP IX blocked the effect of sildenafil. Transfection with HO-1 siRNA significantly reduced the protective effect of sildenafil on the loss of MTT reduction ability and MPT induction in AGE-treated cells. Conclusion : Taken together, our results suggested that sildenafil provides beneficial effect to protect the HT-22 hippocampal neuronal cells against AGE-induced deterioration of mitochondrial integrity, and upregulation of HO-1 is involved in the underlying mechanism.

• 한국토양비료학회지
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• 제44권1호
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• pp.146-159
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• 2011

The continuous increase in the production of metals and their subsequent release into the environment has lead to increased concentration of these elements in agricultural soils. Because microbes are involved in almost every chemical transformations taking place in the soil, considerable attention has been given to assessing their responses to metal contaminants. Short-term and long-term exposures to toxic metals have been shown to reduce microbial diversity, biomass and activities in the soil. Several studies show that microbial parameters like basal respiration, metabolic quotient, and enzymatic activities, including those of oxidoreductases and those involved in the cycle of C, N, P and other elements, exhibit sensitivity to soil metal concentrations. These have been therefore, regarded as good indices for assessing the impact of metal contaminants to the soil. Metal contamination has also been extensively shown to decrease species diversity and cause shifts in microbial community structure. Biochemical and molecular techniques that are currently being employed to detect these changes are continuously challenged by several limiting factors, although showing some degree of sensitivity and efficiency. Variations and inconsistencies in the responses of bioindicators to metal stress in the soil can also be explained by differences in bioavailability of the metal to the microorganisms. This, in turn, is influenced by soil characteristics such as CEC, pH, soil particles and other factors. Therefore, aside from selecting the appropriate techniques to better understand microbial responses to metals, it is also important to understand the prevalent environmental conditions that interplay to bring about observed changes in any given soil parameter.

• Clinical and Experimental Reproductive Medicine
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• 제45권2호
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• pp.82-87
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• 2018

Objective: Concerns about the safety of assisted reproductive technology (ART) have been raised, as some studies have shown elevated incidence rates of childhood cancer, asthma, allergies, and other diseases in ART-conceived babies. Findings regarding the health of ART-conceived babies are controversial. The present study was conducted to evaluate the prooxidant-antioxidant balance (PAB) in in vitro fertilization (IVF)-conceived mice in comparison to naturally conceived offspring. Methods: Mice (6-8 weeks) were divided into two groups (IVF-conceived and naturally conceived) matched by sex, age, weight, and litter size. A 1-mL blood sample was taken and the sera were separated. The oxidant-antioxidant balance was evaluated using a fast and reliable PAB assay. The results were expressed as $mean{\pm}standard$ deviation. Results: The mean PAB values (HK units) in the IVF-conceived and naturally conceived groups were $59.70{\pm}22.30$ and $54.70{\pm}18.22$, respectively (p= 0.82). Conclusion: Since free radicals contribute to several pathological conditions and antioxidants play an important protective role against oxidative stress, evaluating the oxidant-antioxidant balance is very important. Although the results of this study showed that the quality of the defense mechanism against free radicals was not significantly different between the IVF-conceived and naturally conceived mice, other parameters of metabolic dysfunction need to be measured.

• Parasites, Hosts and Diseases
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• 제51권2호
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• pp.165-175
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• 2013

The fear that schistosomes will become resistant to praziquantel (PZQ) motivates the search for alternatives to treat schistosomiasis. The antimalarials quinine (QN) and halofantrine (HF) possess moderate antischistosomal properties. The major metabolic pathway of QN and HF is through cytochrome P450 (CYP) 3A4. Accordingly, this study investigates the effects of CYP3A4 inhibitor, ketoconazole (KTZ), on the antischistosomal potential of these quinolines against Schistosoma mansoni infection by evaluating parasitological, histopathological, and biochemical parameters. Mice were classified into 7 groups: uninfected untreated (I), infected untreated (II), infected treated orally with PZQ (1,000 mg/kg) (III), QN (400 mg/kg) (IV), KTZ (10 mg/kg)+QN as group IV (V), HF (400 mg/kg) (VI), and KTZ (as group V)+HF (as group VI) (VII). KTZ plus QN or HF produced more inhibition (P<0.05) in hepatic CYP450 (85.7% and 83.8%) and CYT b5 (75.5% and 73.5%) activities, respectively, than in groups treated with QN or HF alone. This was accompanied with more reduction in female (89.0% and 79.3%), total worms (81.4% and 70.3%), and eggs burden (hepatic; 83.8%, 66.0% and intestinal; 68%, 64.5%), respectively, and encountering the granulomatous reaction to parasite eggs trapped in the liver. QN and HF significantly (P<0.05) elevated malondialdehyde levels when used alone or with KTZ. Meanwhile, KTZ plus QN or HF restored serum levels of ALT, albumin, and reduced hepatic glutathione (KTZ+HF) to their control values. KTZ enhanced the therapeutic antischistosomal potential of QN and HF over each drug alone. Moreover, the effect of KTZ+QN was more evident than KTZ+HF.

• Archives of Pharmacal Research
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• 제26권11호
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• pp.979-983
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• 2003

The pharmacokinetic of tolbutamide was studied after the oral administration to normal rabbits or rabbits with mild to medium folate-induced renal failure. The plasma concentrations of tolbutamide were significantly elevated (p<0.05) during 9 to 24 h in rabbits with mild or medium folate-induced renal failure. Consequently, the area under the plasma concentration-time curves (AUC) was significantly higher in mild (p<0.05) and medium (p<0.01) folate-induced renal failure rabbits (i.e., 2906 $\mu$g/mL$.$h for mild renal failure and 4074 $\mu$g/mL$.$h for moderate renal failure) than that in normal rabbits (i.e., 2295 $\mu$g/mL$.$h). The cumulative urinary excretion of tolbutamide was significantly depressed (p<0.05) in medium folate-induced renal failure rabbits (i.e., 3.3 mg) compared with that in normal rabbits (i.e., 5.9 mg). The elimination rate constant (Kel) of tolbutamide was significantly decreased in medium renal failure rabbits (i.e., 0.027 $h^{-1}$) than that in normal rabbits (i.e., 0.044 $h^{-1}$ ); As a result, the terminal half-life of tolbutamide in medium folate-induced renal failure rabbits (i.e., 25.5 h) was significantly longer (p<0.01) than that in normal rabbits (i.e., 15.7 h). The change in pharmacokinetic parameters is consistent with the hypothesis that the alteration is mediated by the depressed metabolic elimination of the drug by the induction of renal failure. Therefore, these observations indicated that the dosage adjustment may be necessary for tolbutamide in patients with renal insufficiency.

• Safety and Health at Work
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• 제8권2호
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• pp.183-188
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• 2017

Background: Recommendations have been proposed for minimum aerobic fitness among firefighters but it is unclear if those criteria relate to performance on the fireground. Less fit individuals fatigue more quickly than fit individuals when working at comparable intensity and may have gait changes, increasing risk of falls. We evaluated the effect of fatigue during a live burn evolution on gait parameters and functional balance comparing them to aerobic fitness levels. Methods: A total of 24 firefighters had gait and balance tested before and after a live burn evolution. Data were stratified by aerobic fitness of greater/less than 14 metabolic equivalents (METs). Results: Analysis of gait cycles measurements before and after the live burn evolution revealed that single leg stance, cycle, and swing time decreased (p < 0.05) but there were no differences in the other measures. There were no differences in time to complete the functional balance test, or errors committed before or after a live burn evolution. When firefighters were sorted by fitness level of 14 METs, there were no differences for errors or time before or after the live burn evolution. Balance data were analyzed using a linear regression. Individuals with lower fitness levels required more time to complete the test. Conclusion: A 14-MET criterion failed to distinguish gait or balance characteristics in this group. However, less fit firefighters did require more time to complete the balance test (p = 0.003). Aerobic fitness alone does not predict gait changes among firefighters following a live burn evolution but does appear to influence functional balance.

• 한국환경농학회지
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• 제31권3호
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• pp.264-270
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• 2012

본 연구에서는 포공영의 에탄올 추출물의 중금속 중독에 의한 손상 억제 효과를 측정하였다. 현대 사회에서 환경으로부터 오염이 우려되는 납과 수은을 실험동물에 노출시켰고, 납과 수은에 노출된 흰쥐에서 포공영이 이러한 중금속 노출로 영향을 받는 체중변화, 간 및 신장에 미치는 영향을 혈액세포분석 및 혈액 내의 생화학적 분자에 대한 조사하였다. 실험 결과, 포공영을 투여 받은 실험군은 중금속 투여로 인하여 발생하는 체중감소의 개선효과가 나타났고, 혈액세포의 변화에 있어서도 중금속 노출로 감소되었던 RBC의 수를 증가시켰고, 증가된 WBC 및 platelet의 수를 정상수준으로 회복시켰다. 간 및 신장의 손상 지표들로 측정한 Bilirubin, ALP, GOT, GPT, LDH, ceatinine 및 BUN에 있어서도 중금속 노출로 증가된 수치를 농도의존적으로 감소시켰다. 또한 혈액내에서의 중금속 잔존량을 측정한 결과, 포공영 추출물 투여로 인하여 농도의존적으로 그 잔존량이 감소하였다. 따라서, 포공영 에탄올 추출물은 체내 노출된 납과 수은에 대한 독성을 완화시켜주는 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권9호
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• pp.1291-1296
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• 2003

Effects of feeding of 9.95 mg free gossypol/kg live weight through cottonseed meal (CSM) were studied in 20 intact male calves fed barley or sorghum as source of cereal during the experimental duration of 210 days. Serum concentration of total protein, albumin, globulin and their ratio did not vary because of protein (gossypol) or cereal sources. Serum level of cholesterol and urea were lower (p<0.05) in sorghum than barley fed calves. Feeding of gossypol through CSM enhanced (p<0.05) serum cholesterol. An interaction between protein and period was observed with respect to serum concentrations of urea, creatinine and alanine transferase. The levels of serum creatinine and alanine transferase increased (p<0.05) following 120 days of experimental feeding in calves fed CSM diets compared to the control animals fed groundnut meal diets. No effect of feeding gossypol was, however, evident on the serum enzymes viz. alanine and aspartate transferases and alkaline phosphatase. Moreover, the source of cereal and protein did not appear to influence the metabolic profile of the calves. Humoral immune response, measured through antibody titre against Brucella abortus S99 innoculation, revealed a delayed and depressed seroreactivity indicative of immunocompromisation because of the phytotoxin gossypol. In conclusion, the feeding of gossypol at the designated levels, although had no deleterious clinico-biochemical manifestations, affected the humoral immune response of the calves.

• Asian-Australasian Journal of Animal Sciences
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• 제33권12호
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• pp.2039-2049
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• 2020

Objective: This study was conducted to provide models to accurately predict nitrogen (N) and phosphorus (P) excretion of dairy cows on smallholder farms in Indonesia based on readily available farm data. Methods: The generic model in this study is based on the principles of the Lucas equation, describing the relation between dry matter intake (DMI) and faecal N excretion to predict the quantity of faecal N (Q_FN). Excretion of urinary N and faecal P were calculated based on National Research Council recommendations for dairy cows. A farm survey was conducted to collect input parameters for the models. The data set was used to calibrate the model to predict Q_FN for the specific case. The model was validated by comparing the predicted quantity of faecal N with the actual quantity of faecal N (Q_FNACT) based on measurements, and the calibrated model was compared to the Lucas equation. The models were used to predict N and P excretion of all 144 dairy cows in the data set. Results: Our estimate of true N digestibility equalled the standard value of 92% in the original Lucas equation, whereas our estimate of metabolic faecal N was -0.60 g/100 g DMI, with the standard value being -0.61 g/100 g DMI. Results of the model validation showed that the R² was 0.63, the MAE was 15 g/animal/d (17% from Q_FNACT), and the RMSE was 20 g/animal/d (22% from Q_FNACT). We predicted that the total N excretion of dairy cows in Indonesia was on average 197 g/animal/d, whereas P excretion was on average 56 g/animal/d. Conclusion: The proposed models can be used with reasonable accuracy to predict N and P excretion of dairy cattle on smallholder farms in Indonesia, which can contribute to improving manure management and reduce environmental issues related to nutrient losses.