• The Korean Journal of Physiology
• /
• 제7권1호
• /
• pp.23-31
• /
• 1973

Numerous factors concern with the absorption of substances through the membrane of the gastrointestinal tract. To simplify the experimental condition, present work has been restricted to observe the disappearance rate of substance from the intestinal loop which was made in the jejunum, 70 cm apart from the pylorus of the adult rabbit. The purpose of the study is to clarify the absorption of urea through the jejunal wall is solely attributable to the concentration difference between the luminal fluid and plasma, and to observe the effect of adding red pepper upon the rate of absorption. The rabbits were anesthetized with nembutal, 35mg/kg I.V. Jejunal loop was made by ligating at 2 spots, 70 cm and 80cm apart from the pylorus. After rinsing with normal saline solution through the polyethylene tubing inserted from the end of the loop, 8 ml of test solution was placed through the same tubing. The test solution contained 200 mg% of urea and 150mg% of polyethylene glycol(M.W. 4,000) in normal saline solution. Right after placing the test solution the first specimen was taken through the tubing, and successive samplings were performed at 5, 10, 20, and 30 minutes. Logarithm of the difference of urea concentration between the luminal fluid and plasma was plotted against time elapsed after the onset of the experiment. If straight line is revealed, it would verify the nature of transport mechanism as diffusion, obeying the Fick's principle. The concentration of polyethylene glycol (PEG) was also measured in order to examine the change in the volume. PEG was used as the marker substance because it is not absorbable in the intestinal tract. Consequently the concentration of PEG relates inversely to the volume of the loop. Instantaneous concentration of urea in the loop times the volume will give the amount of urea remaining in the luminal fluid. The change in the amount of any substance is directly relate to the volume of the compartment and differs from the change in the concentration which is independent of the volume. After completion of the experiment without red pepper, it was added in the test solution and was centrifuged after thorough mixing. Supernatant of the mixture was placed in the loop and similar sampling were performed with the same time intervals that of previous run in order to observe the effects of the red pepper on the passive transport of the water soluble small substance, urea. The results obtained were as follows: 1. Logarithm of the concentration difference of urea between the luminal fluid and plasma was diminished exponentially as time elapsed. The decay constant in the experiment without red pepper was 0.0563/min. By adding red pepper in the test solution as much as the concentration rose to 4,000 mg% and 8,000 mg%, the decay constants were lowered to 0.0493/min and to 0.0506/min, respectively. The time interval by which the concentration difference dropped to one half of the initial value was prolonged. Without red pepper the half concentration time was 13.30 minutes, and by adding extract of red pepper, 15.31 minutes and 15.71 minutes were revealed. 2. The profile of the diminishing rate of tile amount of urea was quite different from that of the concentration because of the change in the volume of the loop during the observed period. 3. By adding the extract of red pepper, it slowed down the rate of absorption of urea in the intestinal loop, suggesting an increase in the diffusional barrier. 4. Larger dosage of red pepper brought an increase in the secretion of intestinal fluid with concomitant expansion of the luminal volume, and the retardation of the absorption of urea was noticed. This effect was largely dependent on the sensitivity of the individual animal to the red pepper, extract. The amount of urea remained after 10 minutes interval was 55.5% of the initial amount in the experiment without red pepper. On the other hand it was not consistent after administration of red pepper, showing 50.6% and 66.5% of the initial figures by adding 400 mg and 800 mg of red pepper in the test solution, respectively. It was postulated that symptom of diarrhea often encountered by taking a hot (red pepper) food might be attributable to the increase of secretion and the retardation of absorption in the intestinal tract.

• Asian-Australasian Journal of Animal Sciences
• /
• 제25권10호
• /
• pp.1389-1394
• /
• 2012

Sheanut cake (SNC), expeller (SNE) and solvent extractions (SNSE) samples were evaluated to determine their suitability in animal feeding. The CP content was highest in SNSE (16.2%) followed by SNE (14.7%) and SNC (11.6%). However, metabolizable energy (ME, MJ/kg) was maximum in SNC (8.2) followed by SNE (7.9) and SNSE (7.0). The tannin phenol content was about 7.0 per cent and mostly in the form of hydrolyzable tannin (HT), whereas condensed tannin (CT) was less than one per cent. The in vitro gas production profiles indicated similar y max (maximum potential of gas production) among the 3 by-products. However, the rate of degradation (k) was maximum in SNC followed by SNE and SNSE. The $t^{1/2}$ (time taken for reaching half asymptote) was lowest in SNC (14.4 h) followed by SNE (18.7 h) and SNSE (21.9 h). The increment in the in vitro gas volume (ml/200 mg DM) with PEG (polyethylene glycol)-6000 (as a tannin binder) addition was 12.0 in SNC, 9.6 in SNE and 11.0 in SNSE, respectively. The highest ratio of $CH_4$ (ml) reduction per ml of the total gas, an indicator of the potential of tannin, was recorded in SNE (0.482) followed by SNC (0.301) and SNSE (0.261). There was significant (p<0.05) reduction in entodinia population and total protozoa population. Differential protozoa counts revealed that Entodinia populations increased to a greater extent than Holotricha when PEG was added. This is the first report on the antimethanogenic property of sheanut byproducts. It could be concluded that all the three forms of SN byproducts are medium source of protein and energy for ruminants. There is a great potential for SN by-products to be incorporated in ruminant feeding not only as a source of energy and protein, but also to protect the protein from rumen degradation and suppress enteric methanogenesis.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2005년도 생물공학의 동향(XVI)
• /
• pp.152-156
• /
• 2005

본 연구에서 수행한 avermectin 생산을 위한 배지 최적화에서 기존의 총 avermectin의 함량 10 mg/L를 470 mg/L까지 증가시켰으며, 이 중 광범위 활성을 가지는 avermectin B1도 50%에 달했다. 최적화된 배지 조성은 50 g/L fructose, 30 g/L malt extract, 5 g/L casamino acid, 2.5 g/L PEG 3,350, and 1 g/L $K_{2}HPO_{4}$이다. $K_{2}HPO_{4}$와 fructose, malt extract가 avermectin 생합성에 크게 작용하는 것으로 추정된다.

• 한국염색가공학회지
• /
• 제13권6호
• /
• pp.33-33
• /
• 2001

The physical properties and the dyeability of the easily dyeable polyester yarn(EDY) were investigated and compared with those of regular polyester (REG-PET). The EDY, copolymerized with small amount of polyethylene glycol(PEG), showed higher intensity of aliphatic CH peak in IR spectrum, lower density and lower compactness than those of the REG-PET from the analysis of IR, density gradient column and XRD respectively. In the physical properties, the EDY has lowers $T_g,\;T_m$, specific stress and initial modulus, and also has higher strain than that of the REG-PET. The EDY can be dyed under atmospheric pressure and its dyeing rate was faster than REG-PET due to low $T_d$, and this seems to be caused by the increased flexibility of Polymer chain in amorphous region of the EDY due to the copolymerization of PEG.ns being within the experimental error, the average values of lifetim.
$\tau$(t) are taken for further calculations. Rate constants such as Stern-Volmer quenching constants K$_{sv}$, quenching rate parameters k$_q$ and k''$_q$, static quenching constant V and kinetic distance r are determined using the modified Stern-Volmer eq.
tion and sphere of action static quenching model. In order to see whether the reactions are diffusion limited, equations k$_q$ = e$^{-Eq/RT}$ and k''$_q$ = e$^{-Eq/RT}$ are used to determine the values of E$_q$ and E''$_q$, the activati.
energies for collisional quenching and the values of E$_q$ are 14.53, 17.28 and 16.20 kJ mole$^{-1}$ for MPNO1, MPNO2 and 2-PI respectively and the values of E''$_q$ are 14.62 and 17.73 for MPNO1 and MPNO2 respectively. From the magnitudes of various quantities it has.
een concluded that the reactions are diffusion limited and the observed positive deviations in the S-V plot are due to static and dynamic quenching.

• 한국작물학회지
• /
• 제38권6호
• /
• pp.507-512
• /
• 1993

담배종자는 매우 미세하기 때문에 육묘과정에서 많은 노동력이 소요된다. 또 담배종자는 보통 2월 하순경부터 조기에 파종하는 경향이므로 저온조건에서의 발아의 안정성이 요구된다. 따라서 저온조건에서 발아가 촉진되고 또한 균일한 묘를 확보하기 위한 기술은 담배종자를 묘상에 직파했을 경우에 반드시 필요한 요건이 된다. 따라서 본시험에서는 파종 전에 담배종자를 여러 가지 방법으로 전처이하여 발아속도의 촉진 및 묘의 균일성에 미치는 영향 등을 조사하여 육묘의 성력화를 위한 기초자료를 제공하고자 하였다. 1. 파종 전 처리로 인하여 최종 발아율에는 영향을 미치지 않았으나 발아속도, 온실에서의 출현속도는 SMP, PEG, DPI처리에서 모두 향상되었으며 특히 SMP처리에서 월등하였다. 2. SMP처리에서 묘의 생장도 가장 켰고 아울러 묘가 가장 균일하였다. 3. SMP처리시 처리재료로 사용된 Agro-Lig의 수분함량은 일정량이상일 경우에 전처리효과에 큰 영향이 없는 것으로 나타났고 처리시의 온도는 높은 온도(2$0^{\circ}C$)에서 처리한 것이 낮은 온도(15$^{\circ}C$)에서 처리한 것보다 정의 방향으로 발아속도 및 출현속도에 영향이 켰다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권23호
• /
• pp.10281-10287
• /
• 2015

Background: Development of a nanosized polymeric delivery system for erlotinib was the main objective of this research. Materials and Methods: Poly caprolactone-polyethylene glycol-polycaprolactone (PCEC) copolymers with different compositions were synthesized via ring opening polymerization. Formation of triblock copolymers was confirmed by HNMR as well as FT-IR. Erlotinib loaded nanoparticles were prepared by means of synthesized copolymers with solvent displacement method. Results: Physicochemical properties of obtained polymeric nanoparticles were dependent on composition of used copolymers. Size of particles was decreased with decreasing the PCL/PEG molar ratio in used copolymers. Encapsulation efficiency of prepared formulations was declined by decreasing their particle size. Drug release behavior from the prepared nanoparticles exhibited a sustained pattern without a burst release. From the release profiles, it can be found that erlotinib release rate from polymeric nanoparticles is decreased by increase of CL/PEG molar ratio of prepared block copolymers. Based on MTT assay results, cell growth inhibition of erlotinib has a dose and time dependent pattern. After 72 hours of exposure, the 50% inhibitory concentration (IC50) of erlotinib hydrochloride was appeared to be $14.8{\mu}M$. Conclusions: From the obtained results, it can be concluded that the prepared PCEC nanoparticles in this study might have the potential to be considered as delivery system for erlotinib.

• 한국미생물·생명공학회지
• /
• 제19권4호
• /
• pp.356-361
• /
• 1991

식물근부병의 방제균으로 선발된 Bacillus subtilis YBL-7의 식물부균 Fusarium solani에 대한 길항력을 유전공학적 조작에 의해 다목적으로 증강시킬 수 있는지를 타진하기 위해 외부유전자인 Bacillus pasteurii의 urease 유전자를 생물방제균 B.subtilis YBL-7내 도입자하고자 시도하였다. 외부 urease 유전자는 B.pasteurii의 urease gene을 shuttle vector인 pGR71의 HindII site에 삽입하여 E.coli내에서 발현시킨 pGU66을 사용하여 형질전환시켰으며 이때의 최적 형질전환조건과 도입된 urease 유전자의 발현을 조사해 보았다.

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제6권5호
• /
• pp.326-331
• /
• 2001

With the aim of developing of pH-sensitive controlled drug release system, a poly(Llysine) (PLL) based cationic semi-interpenetrating polymer network (semi-IPN) has been synthesized. This cationic hydrogel was designed to swell at lower pH and de-swell at higher pH and therefore be applicable for achieving regulated drug release at a specific pH range. In addition to the pH sensitivity, this hydrogel was anticipated to interact with an ionic drug, providing another means to regulate the release rate of ionic drugs. This semi-IPN hydrogel was prepared using a free-radical polymerization method and by crosslinking of the polyethylene glycol (PEG)-methacrylate polymer through the PLL network. The two polymers were penetrated with each other via interpolymer complexation to yield the semi-IPN structures. The PLL hydrogel thus prepared showed dynamic swelling/de-swelling behavior in response to pH change, and such a behavior was influenced by both the concentrations of PLL and PEG-methacrylate. Drug release from this semi-IPN hydrogel was also investigated using a model protein drug, streptokinase. Streptokinase release was found to be dependent on its ionic interaction with the PLL backbones as well as on the swelling of the semi-IPN hydrogel. These results suggest that a PLL semi-IPN hydrogel could potentially be used as a drug delivery platform to modulate drug release by pH-sensitivity and ionic interaction.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• 제19권3호
• /
• pp.153-161
• /
• 2016

This paper covers algorithms for the management of regurgitation, constipation and infantile colic in infants. Anti-regurgitation formula may be considered in infants with troublesome regurgitation, while diagnostic investigations or drug therapy are not indicated in the absence of warning signs. Although probiotics have shown some positive evidence for the management of functional gastrointestinal disorders (FGIDs), the evidence is not strong enough to make a recommendation. A partially hydrolyzed infant formula with prebiotics and ${\beta}$-palmitate may be considered as a dietary intervention for functional constipation in formula fed infants. Lactulose has been shown to be effective and safe in infants younger than 6 months that are constipated. Macrogol (polyethylene glycol, PEG) is not approved for use in infants less than 6 months of age. However, PEG is preferred over lactulose in infants >6 months of age. Limited data suggests that infant formula with a partial hydrolysate, galacto-oligosaccharides/fructo-oligosaccharides, added ${\beta}$-palmitate may be of benefit in reducing infantile colic in formula fed infants in cases where cow's milk protein allergy (CMPA) is not suspected. Evidence suggests that the use of extensively hydrolyzed infant formula for a formula-fed baby and a cow's milk free diet for a breastfeeding mother may be beneficial to decrease infantile colic if CMPA is suspected. None of the FGIDs is a reason to stop breastfeeding.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• 제23권1호
• /
• pp.26-34
• /
• 2020

Purpose: To compare the clinical features, diagnostic findings, and medications of children with infrequent bowel movements or fecal soiling. Methods: This study enrolled 333 children (189 male; age range, 1 month to 18 years) diagnosed with functional constipation by Rome III or IV criteria. We classified them into 3 groups (infrequent bowel movement without fecal soiling [G3-a], infrequent bowel movement with fecal soiling [G3-b], and fecal soiling only [G3-c]) and into 2 subgroups of fecal soiling (G2-b) or not (G2-a). Retrospective data on clinical characteristics, colon transit time (CTT) test results, and medications were collected. The Wilcoxon rank-sum test, Kruskal-Wallis test, Chi-square test, and Fisher's exact test were used for the statistical analysis. Results: The median age (months) and interquartile range (IQR) was 33 (45) in G3-a, 54 (40) in G3-b, and 73 (48) in G3-c (p<0.0001). G3-c had the latest onset (median, 18; IQR, 18; p=0.0219) and longest symptom duration (24 [24], p=0.0148). PEG 4000 was used in 60.6% (G3-a), 96.8% (G3-b), and 83.2% (G3-c) of patients (p<0.0001). The median age (months) and IQR were 33.0 (45.0) in G2-a and 63.5 (52.5) in G2-b (p<0.0001). G2-b had later onset (median, 12; IQR, 19.5; p=0.0062) and longer symptom duration than G2-a (24 [12], p=0.0070). PEG 4000 was used in 60.6% (G2-a) and 88.3% (G2-b) of children (p<0.0001). No statistically significant intergroup differences were seen in maintenance laxative dose, CTT, or CTT type. Conclusion: Infrequent bowel movement and fecal soiling represent the advanced stage of chronic functional constipation.