• Asian-Australasian Journal of Animal Sciences
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• v.2 no.4
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• pp.583-590
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• 1989

Increasing levels of ammonia-N in the rumen fluid used for in vitro incubation were achieved by supplementation of the ration of the donor cows with urea and by addition of urea either with or without glucose to the rumen fluid after collection. The ration of the donor animals consisted of wheat straw (80%) and maize silage (20%). During the second half of the experiment the basal ration was supplemented with a mineral mixture. Wheat straw, Guinea grass and two rice straw varieties were incubated with the various kinds of rumen fluid. Parameters studied were: solubility, apparent organic matter disappearance after 48 hours of incubation ($OMD_{48}$), rate of organic matter degradation from 0 to 24 hours of incubation ($k_1$) and from 24 to 95 hours ($k_2$). The concentration of ammonia-N in the rumen fluid at which 95% of the maximal $OMD_{48}$ and k1 were reached (88.2 and 100.0 mg/l) were independent of the feed. With regard to the $k_2$ the required ammonia-N concentration to reach 95% of the maximal $k_2$ differed per feed. Mineral supplementation increased the OMD48 and $k_1$, but not the solubility and $k_2$. Glucose addition in combination with urea had no beneficial effect compared to urea supplementation alone.

• Journal of Pharmaceutical Investigation
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• v.19 no.4
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• pp.195-202
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• 1989

In attempt to improve the chemotherapeutic activity of adriamycin, adriamycin-entrapped HSA microspheres were prepared and investigated by the various in vitro experiments. The shape, surface characteristics and size distribution of HSA microspheres are observed by scanning electron microscopy. The in vitro drug release, albumin matrix degradation by protease of HSA microspheres were studied. The shape of HSA microspheres were spherical and the surface was smooth and compact. The size of HSA microspheres ranged from 0.4 to $2.5\;{\mu}m$ and have average diameters of 0.5 to $0.7\;{\mu}m$. The size distribution of HSA microspheres prepared by ultrasonication was mainly affected by albumin concentration and heating time in the process of hardening. In in vitro, almost all adriamycin was released from HSA microspheres for 8 hr. Analysis of the resulting adriamycin release profiles demonstrated that adriamycin is released from the microspheres in two distinct steps, a fast phase (until 30 min) followed by a much slower sustained release phase. Drug release, which is due to diffusion, was depended on the rate of matrix hydration. Drug release was largely affected by albumin concentration and heating temperature during the process of hardening. Albumin matrix degradation of HSA microspheres was affected by heating temperature and albumin concentration. Higher temperature and longer times generally produce harder, less porous, and slowly degradable microspheres.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.5
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• pp.199-203
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• 2004

Feasibility of 3Y-TZP for dental implant abutment was evaluated under the Hertzian cyclic fatigue by examining the extent of the indentation damage and strength degradation. Fatigue test was conducted at contact loads of 500 to 3000 N and up to $10^6$ cycles in exact in vitro environments. At 500 N, no strength degradation and crack generation was observed up to $5\times10^5$ contact cycles. As load rose, the dramatic reduction in strength was observed when the damage transition from ring to radial crack occurred. The. extent of strength degradation was more pronounced in vitro environment probably due to chemical corrosion of artificial saliva through cracks introduced during large numbers of contacts.

• Journal of the Korean Ceramic Society
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• v.41 no.1
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• pp.69-75
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• 2004

The degree of the indentation damage and strength degradation for 3Y-TZP ceramics and (Y,Nb)-TZP/$Al_2O_3$ dental implant composites was investigated under the Hertzian cyclic fatigue. Fatigue tests were conducted at contact loads of 500 to 3000 N and up to $10^6$ cycles in exact in vitro environments. At 500 N, no strength degradation and crack generation was observed up to $5{\times}10^5$ contact cycles. Fatigue properties of 3Y-TZP ceramics was superior to (Y,Nb)-TZP/ㅍ composites due to stress relief caused by the phase transformation from tettagonal to monoclinic phase. As contact load increased, the drastic reduction in strength was found when the damage transition from ring to radial crack occurred. The extent of strength degradation was more pronounced in vitro environments probably due to chemical corrosion of artificial saliva through cracks introduced during large numbers of contacts.

• BMB Reports
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• v.34 no.2
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• pp.118-122
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• 2001

The translocation of ribose-binding protein (RBP) into the inverted membrane vesicles (IMV) of Escherichia coli and eukaryotic microsomes was studied using the in vitro translation/translocation system. It was found that RBP was translocated into heterologous eukaryotic microsomes co-translationally, as well as post-translationally However, RBP was translocated only past-translationally into IMV. Degradation fragments of RBP with the molar mass of 14 and 16 kDa were produced during the translocation into IMV However, the amount of the degradation products decreased and the mature form of RBP appeared in the presence of phenylmethylsulfonyl fluoride (PMSF). PMSF and GTP accelerated the translocation of RBF It was also found that SecB enhanced the post-translational translocation of RBP It appears that RBP is translocated via at least two targeting paths.

• Korean Journal of Organic Agriculture
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• v.26 no.2
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• pp.281-296
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• 2018

This study was conducted to evaluate the effect of different processing of rice on rumen fermentation in in vitro and in situ experiments. Different processing treatments (extruding, roasting, and steaming) were used in this study and all treatments were ground through a cyclone mill (Foss, Hillerød, Denmark) fitted with a 1 mm screen. Non-treated rice was considered to a control substrate. Then, all treatments were used in in vitro and in situ experiments. Total gas production and dry matter digestibility in control were lower than any other treatment at all incubation times (P<0.01). The lowest ammonia nitrogen ($NH_3-N$) concentration was observed in control among treatments at 6, 12, and 24 h incubation (P<0.01). Extruding had a highest total volatile fatty acids (VFA) concentration at 6, 12 h incubation (P<0.01) and Steaming exhibited a highest total VFA at 24 h (P<0.01). The lowest total VFA concentration was observed in control at 6, 12, and 24 h (P<0.01). In an in situ, The highest value of soluble fraction, degradation rates, effective degradability was observed in extruding (P<0.01). It was considered that feed processing increased dry matter digestibility, total VFA concentration, and decreased pH as well as $NH_3-N$ concentration indicating that processing may increase nutrient degradation of rice in the rumen.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.343-345
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• 1989

• Journal of Korean Dental Science
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• v.14 no.1
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• pp.12-25
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• 2021

Purpose: (i) To evaluate the biologic properties of a bi-layered 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride-cross-linked collagen membrane (CCM) in vitro. (ii) To assess the efficacy of CCM for localized bone regeneration in vivo. Materials and Methods: Biodegradation of CCM compared to a native collagen membrane (NCM) was assessed in vitro. In vivo, twelve male New Zealand White rabbits were used. Four calvarial, circular defects (diameter 8 mm) were created in each animal. The sites were randomly allocated to i) CCM+biphasic calcium phosphate (BCP) (CCM-BCP group), ii) CCM alone (CCM), iii) BCP alone (BCP) and, iv) negative control (control). Animals were sacrificed at 2 (n=6) and 8 weeks (n=6). Outcome measures included: micro-computed tomography (μCT) analysis (total augmented volume [TAV], new bone volume) and histomorphometry (total augmented area [TAA], newly formed bone, remaining membrane thickness [RMT]). Result: CCM was more resistant to degradation than NCM. μCT analysis showed CCM-BCP (196.43±25.30 mm³) and BCP (206.23±39.13 mm³) groups had significantly (P<0.01) larger TAV than the control (149.72±12.28 mm³) after 8 weeks. Histomorphometrically, CCM-BCP group (17.75±5.97 mm²) had significantly (P<0.01) greater TAA compared to the CCM group (7.74±2.25 mm²) and the control (8.13±1.81 mm²) after 8 weeks. After 8 weeks, RMT was reduced by 67%. Conclusion: CCM can be a favorable choice of barrier membrane when performing guided bone regeneration (GBR) in localized bone defects. CCM has better resistance to degradation than the natural collagen membrane, in vitro. In vivo, CCM provides an advantageous integration of prolonged barrier function and biocompatibility for GBR.

• Animal Bioscience
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• v.35 no.3
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• pp.422-433
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• 2022

Objective: Two follow-up studies (exp. 1 and 2) were conducted to determine the effects of L-glutamine (L-Gln) supplementation on degradation and rumen fermentation characteristics in vitro. Methods: First, rumen liquor from three cannulated cows was used to test L-Gln (50 mM) degradation rate and ammonia-N production at 6, 12, 24, 36, and 48 h after incubation (exp. 1). Second, rumen liquor from two cannulated steers was used to assess the effects of five levels of L-Gln including 0% (control), 0.5%, 1%, 2%, and 3% at 0, 3, 6, 12, 24, 36, and 48 h after incubation on fermentation characteristics, gas production, and degradability of nutrients (exp. 2). Results: In exp. 1, L-Gln degradation rate and ammonia-N concentrations increased over time (p<0.001). In exp. 2, pH was reduced significantly as incubation time elapsed (p<0.001). Total gas production tended to increase in all groups as incubation time increased. Acetate and propionate tended to increase by increasing glutamine (Gln) levels, whereas levels of total volatile fatty acids (VFAs) were the highest in 0.5% and 3% Gln groups (p<0.001). The branched-chain VFA showed both linear and quadratic effects showing the lowest values in the 1% Gln group particularly after 6 h incubation (p<0.001). L-Gln increased crude protein degradability (p<0.001), showing the highest degradability in the 0.5% Gln group regardless of incubation time (p<0.05). Degradability of acid detergent fiber and neutral detergent fiber showed a similar pattern showing the highest values in 0.5% Gln group (p<0.10). Conclusion: Although L-Gln showed no toxicity when it was supplemented at high dosages (2% to 3% of DM), 0.5% L-Gln demonstrated the positive effects on main factors including VFAs production in-vitro. The results of this study need to be verified in further in-vivo study.

• Korean Journal of Agricultural Science
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• v.26 no.2
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• pp.25-32
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• 1999

An in vitro study was conducted to examine the effects of the addition of activated charcoal (AC) on the ruminal fermentation characteristics, nutrient disappearance, and ruminal gas production. AC was added at the levels of 0.00, 0.25, and 0.50 % to each of the four types of diets (roughage/concentrate ratio : 8/2, 6/4, 4/6 and 2/8), respectively. Although not significant, ruminal pH tended to increase by adding AC, and as the concentrate level increased, ruminal pH decreased (P<0.05). Acetate concentration and acetate/propionate molar ratio tended to decrease in AC diets. but molar % of propionate tended to increase by the addition of AC. Ruminal degradation of dry matter, crude protein, NDF, ADF, and hemicellulose in AC diets tended to increase than in non-AC diet, however, no tendency in ruminal degradation of crude fat was observed. As the concentrate level increased, rumunal degradation of dry matter and nutrients in AC diets increased significantly(P<0.05). Ruminal gas production tended to decrease in the 0.50 % AC diets, however, it tended to increase in high roughage diets. Although there appeared some beneficial effects in adding AC to ruminant diets in this study, more works should be done with AC before we can make clear conclusion on the use of AC in the ruminant diets.