• 제목/요약/키워드: globules

검색결과 137건 처리시간 0.025초

유지방구막의 주요 성분인 PAS-4 당단백질의 구조 해석 (Structural Analysis of PAS-4 Glycoprotein from Milk Fat Globule Membrane)

  • 황보식
    • Journal of Dairy Science and Biotechnology
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    • 제15권1호
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    • pp.27-32
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    • 1997
  • Most lipids in milk are dispetsed as the form of fat globules. Apical portion of plasma membrane is coated with fat globules, which are synthesized from mammary epithelial cells and then secreted into the lumen. The unique phenomenon in separation of the plasma membrane from the cell is observed only in mammary system. It has been suggested that milk fat globule membrane(MFGM) is formed from endoplasmic reticulum, Golgi apparatus, secretory granule to plasma membrane. For this reason MFGM is important for nuderstanding the structure and function of biological membrane. Because MFGM also plays an important role in inhibition of lipase action, stimulation of nutrient digestion and absorption, emulsion or function as natural liposome, study of the major components in MFGM will provide the opportunity for more broad industrial uses of MFGM in the future.

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EFFECTS OF DIFFERENTIAL ROTATION ON THE CO LINE PROFILES

  • Park, Y.S.;Yun, H.S.;Hong, S.S.;Lee, H.M.
    • 천문학회지
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    • 제25권2호
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    • pp.67-78
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    • 1992
  • Effects of cloud rotation 011 the profiles of CO J=$1{\rightarrow}0$ lines arc investigated by theoretically general ing line profiles under physical conditions similar to t he ones in large globules. The synthesized profiles are presented and their characteristics are discussed. It is found that when the Doppler shift of the observed CO lines is interpreted as the rotation velocity, the optically thin $^{13}CO$ lines underestimate the rotation velocity by up to 10 percents, while the self-reversed optically thick $^{12}CO$ lines overestimate the velocity up to 20 percents. The optically thin line is shown to be of use in probing the distribution of rotation velocity in dark globules.

Roles of Milk Fat Globule Membrane on Fat Digestion and Infant Nutrition

  • Chai, Changhoon;Oh, Sejong;Imm, Jee-Young
    • 한국축산식품학회지
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    • 제42권3호
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    • pp.351-371
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    • 2022
  • Milk fats are present as globules emulsified in the aqueous phase of milk and stabilized by a delicate membrane architecture called milk fat globule membrane (MFGM). The unique structure and composition of the MFGM play an important role in fat digestion and the metabolic programming of neonates. The objective of this review is to compare the structure, composition, and physicochemical characteristics of fat globules in human milk, bovine milk, and infant formula. It provides an overview of the fat digestion process and enzymes in healthy infants, and describes the possible roles of the MFGM in association with factors affecting fat digestion. Lastly, the health benefits of the MFGM on infant nutrition and future perspectives are discussed with a focus on brain development, metabolic response, and gut health.

Effect of the Difference in the High Molecular Weight Fraction of Whey Between Cow's Milk and Goat's Milk on Creaming Phenomenon

  • Masuda, T.;Taniguchi, T.;Suzuki, K.;Sakai, T.;Morichi, T.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권3호
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    • pp.351-357
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    • 2001
  • The rapid formation of a cream line cannot be observed in raw goat's milk standing at a low temperature. Although the poor creaming ability of goat's milk has been considered to be due to the small size of milk fat globules and the lack of euglobulin capable of being adsorbed on milk fat globules, there is much left to study. The present work attempted to elucidate a factor for poor creaming ability of goat's milk. The creaming ability of the experimental milks reconstituted from creams and skim milks separated from cow's milk or goat's milk was measured by the volume of the cream layer and the fat content of bottom layer. The polypeptides composition of the P1 the fraction (i.e., the high molecular weight fraction eluted near the void volume obtained by the gel filtration of whey) and milk fat globule membrane prepared from both milks were compared. It was found that the promotion of creaming originated from goat's skim milk was lower than that from cow's skim milk. The P1 fraction in goat's skim milk was less than that in cow's skim milk. The polypeptide (M.W. $4.3{\times}10^4$), found in the P1 fraction of cow's milk was not found in the P1 fraction of goat's milk. It is suggested that the poor creaming ability of goat milk is caused mainly by the difference from cow milk in the amount and the composition of the P1 fraction.

Ultrastructural Studies on Oocyte Differentiation and Vitellogenesis in the Oocytes of Female Kareius bicoloratus in Western Korea

  • Jun, Je-Cheon;Gang, Hee Woong;Lee, Ki-Young
    • 한국발생생물학회지:발생과생식
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    • 제22권3호
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    • pp.213-223
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    • 2018
  • Ultrastructural studies on oocyte differentiation and vitellogenesis in the oocytes of female Kareius bicoloratus were investigated by transmission electron microscopy. The Golgi complex in the cytoplasm is involved in the formation of yolk vesicles that contain yolk carbohydrates in the yolk vesicle of oocytes in the early vitellogenic phase. In this phase, many pinocytotic vesicles (PVs), which are formed by pinocytosis, contain yolk precursors (exogenous substances). These substances are associated with exogenous heterosynthetic vitellogenesis. In yolked oocytes in the late vitellogenic phase, two morphologically different bodies, which formed by modified mitochondria, appear in oocytes. One is a multivesicular body (synthesized by autosynthetic vitellogenesis), and the other is a yolk precursor (an exogenous substance formed by heterosynthetic vitellogenesis). The multivesicular bodies (MVB) are taken into the yolk precursors (YP) and are transformed into primary yolk globules. However, after the YP mix with exogenous PVs near the zona pellucida, they are transformed into primary yolk globules. Vitellogenesis of this species occurs via endogenous autosynthesis and exogenous heterogenesis. Vitellogenesis occurs through endogenous autosynthesis, which involves the combined activity of the Golgi complex, mitochondria and MVB formed by modified mitochondria. However, heterosynthesis involves pinocytotic incorporation of extraovarian precursors (such as vitellogenin in the liver) into the zona pellucida (via granulosa cells and thecal cells) of the yolked oocyte.

난소에서 발생한 내배엽동 종양의 복수의 세포학적 소견 - 1례 보고 - (Cytologic Features of Endodermal Sinus Tumor of Ovary in the Ascitic Fluid - Report of a Case -)

  • 정은선;김영신;강창석;심상인
    • 대한세포병리학회지
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    • 제6권2호
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    • pp.204-208
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    • 1995
  • The cytologic findings of endodermal sinus tumor of the ovary are reported. The cytologic preperations were obtained from ascitic specimens. The findings on Papanicolaou-stained smears included a clean background and poorly preserved atypical cells loosely arranged in irregular or papillary groups. At high magnification, the cells had ill-defined and microvacuolated cytoplasms, with an increased nuclear-cytoplasmic ratio and prominent nucleoli. Hyaline globules characteristic of the alpha-fetoprotein (AFP)-synthesizing cells of endodermal sinus tumor were observed within the cells with periodic-acid-Schiff(PAS) stain. The presence of PAS-positive hyaline globules can be regarded, therefore, as a diagnostic clue to endodermal sinus tumor in an appropriate clinical setting and in the presence of AFP production. The cytologic findings in a cell block is important, in addition to smears, to obtain more diagnostic clues. A preliminary cytomorphologic diagnosis of this highly malignant tumor is valuable as a guide in planning further immunocytochemical and serologic studies.

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Quality characteristics of plant-based whipped cream with ultrasonicated pea protein

  • Insun Kim;Kwang-Deog Moon
    • 한국식품저장유통학회지
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    • 제31권1호
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    • pp.64-79
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    • 2024
  • The rise in popularity of vegetarian and plant-based diets has led to extensive research into plant-based whipped creams. Whipped cream is an oil-in-water emulsion that creates foam through whipping, stabilizing the foam with proteins and fats. Pea protein is an excellent emulsifier and foaming agent among plant-based proteins, but its application in whipped cream is currently limited. The objective of this study was to investigate the quality characteristics of plant-based whipped cream made with ultrasonicated pea protein. The whipped creams were evaluated based on their quality characteristics. A commercially available dairy whipped cream (CON) was used as a control. Plant-based creams were evaluated using pea protein solution, cocoa butter, and canola oil to produce un-ultrasonicated pea protein whipped cream (PP) and ultrasonicated pea protein whipped cream (UPP) at 360 W for 6 min. UPP significantly reduced whipping time and foam drainage compared with CON and PP, resulting in significantly increased overrun, fat destabilization, and hardness. Optical microscopy showed that UPP had smaller fat globules and bubble size than PP. The fat globules of UPP and CON were mostly below 5 ㎛, whereas those of PP were distributed at 5-20 ㎛. Finally, ultrasonication significantly improved the overrun, foam drainage, fat destabilization, and hardness of UPP, which are significant quality characteristics of whipped creams. Therefore, ultrasonicated plant-based pea protein whipped cream is believed to be a viable alternative to dairy whipped cream.

면역황금표지법에 의한 일록춘폐흡충의 발육단계별 항원성부위 (Ultrastructural antigenic localization in Paragonimus iloktsuenesis during developmental stage by immunogold labeling method)

  • 김훈식;이옥란
    • Parasites, Hosts and Diseases
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    • 제33권4호
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    • pp.365-376
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    • 1995
  • 일록춘폐흡충(Poragonimus iloktsuenensis)의 표피층, 장상피층 및 난황선의 조직항원 성을 발육단계별로, 면역황금표지법(immunogoldlabelingmethod)으로 관찰하였다. 일록춘폐흡충 으로 감염건 횐쥐(Sprague-Dawley)로 부터, 감염후 2주 3주, 4주, 5주 및 33주에 적출한 충체를 항원으로 사용하였고, 감염 후 10주의 흰쥐혈청을 항체로 사용하였다 조직항원성은 조직에 표지된 황금입자로 판정하였다. 표피층은 유약충으로부터 성충에 이르는 발육과정중 전반적으로 황금입자 표지가 많지 않았고 충체가 성숙되어감에 따라서 황금입자 표지가 다소 드물어지는 경향이 있었으나, 충체 개체별 항원 강도에 차이가 많았다. 장상피층과 난황선은 충체의 발육단계에 관계없이 많은 수의 황금입자가 표지되어 강한 항원성을 나타내었다. 이 실험의 결과, 일록춘폐흡충의 표피층 장강피층, 및 난황선은 중요한 조직항원 부위로 보이나, 표피층은 항원성이 낮은 편이고, 발육단계 및 개체별로 항인강도에 차이가 있었다. 장상피층 및 난황선도 개체별로 황금입자 표지강포에 다소의 차이는 있었으나 충체의 발육단계에 관계없이 계속해서 강한 항원성이 유지되는 조직부위로 보인다.

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Tin Pest 방지 솔더합금의 크리프 특성 (Creep Deformation Behaviors of Tin Pest Resistant Solder Alloys)

  • 김성범;유진;손윤철
    • 마이크로전자및패키징학회지
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    • 제12권1호
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    • pp.47-52
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    • 2005
  • 전세계 전자패키지 산업에서 납(Pb) 사용에 대한 환경규제 움직임이 본격화되고 있어 새로운 무연솔더의 개발이 활발히 이루어지고 있다. 게다가 무연솔더의 신뢰성에 대한정보가 아직까지 많이 부족한 실정이다 무연솔더의 신뢰성에 영향을 줄수 있는 것 중의 하나가 Sn pest라고 알려진 동소체 변태이다. Sn pest가 형성될 때 동반되는 부피의 증가는 솔더 조인트의 신뢰성을 저하시킨다. 이미 보고된 바에 따르면, Sn 고용도가 있는 원소(Pb, Bi, Sb)들을 첨가시킬 경우 Sn pest가 효과적으로 억제된다. 그러나 Sn pest를 억제하는 합금에 대한 기계적인 특성에 연구가 거의 이루어지지 않았다. 본 연구에서는 Sn과 Sn-0.7Cu를 기반으로 하여 Bi, Sb을 첨가한 솔더 합금을 사용하여 lap shear크리프 실험을 하였다. 본 연구에서 사용한 합금들의 변형율은 전체적으로 Sn-3.5Ag를 기반으로 하는 합금들보다 높았다. 파괴까지 이르는 변형량은 Sn-0.5Bi가 가장 크고 Sn-0.7Cu-0.5Sb 합금이 가장 작았는데 이러한 경향은 Sn-0.5Bi 합금의 파단면에 Sn globules이 길게 늘어나 있고 Sn-0.7Cu-0.5Sb 합금에서는 더 짧은 Sn globules 이 관찰되는 결과와 일치하였다.

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