• 제목/요약/키워드: In-vitro study

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미세튜브 내부를 흐르는 혈액유동의 유변학적 특성에 대한 in-vitro 연구 (In-vitro Study on Hemorheological Behaviors of Blood Flow Through a Micro Tube)

  • 강명진;지호성
    • 대한의용생체공학회:의공학회지
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    • 제31권2호
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    • pp.99-105
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    • 2010
  • In order to obtain velocity profile of blood flow with high spatial resolution, a micro PIV technique consisted of a fluorescent microscope, double-pulsed YAG laser, cooled CCD camera was applied to in-vitro blood flow experiment through a micro round tube of a diameter $100{\mu}m$. Velocity distributions of blood flow for rabbit were obtained. The viscosity profiles for shear rate were found at flowing condition. To provide hemorheological characteristics of blood flow, the viscosities for shear rate were evaluated. The viscosity of blood also steeply increase by decreasing shear rate resulting in Non-Newtonian flow, especially in low shear rate region caused by RBC rheological properties. The results show typical characteristics of Non-Newtonian characteristics from the results of velocity profile and viscosity for blood flow. From the inflection points, cell free layer and two-phase flow consisted with plasma and suspensions including RBCs can be separated.

Abridged Region from Escherichia coli Periplasmic Stress Sensor DegS Acts as Plasminogen Activator In Vitro

  • Junpeng, Yan;Ko, Juho;Qi, Yipeng
    • Journal of Microbiology and Biotechnology
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    • 제17권4호
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    • pp.594-599
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    • 2007
  • It is well known that the Escherichia coli inner membrane-bound protease DegS is a periplasmic stress sensor for unfolded outer membrane proteins (OMPs). Previous studies have also shown that the outer membrane protease OmpT activates plasminogen in vitro and this may be exploited by bacteria in the course of pathogenesis. However, there has been no research on the plasminogen activation ability of the important periplasmic protein DegS. Accordingly, in this study, the whole-length and truncated degS genes were separately overexpressed in Escherichia coli, the recombinant proteins purified by affinity chromatography, and their plasminogen activator role tested in vitro. The results suggested that the whole-length DegS was able to activate plasminogen on a plasma plate. The truncated form of DegS (residues 80-345), designated ${\Delta}DegS$, also acted as a plasminogen activator, as confirmed by different assays. The serine protease property of ${\Delta}DegS$ was verified based on the complete inhibition of its enzyme activity by PMSF (phenylmethanesulfonyl fluoride). Therefore, the present results indicate that DegS is a plasminogen activator in vitro.

In vitro Skin Irritation Test of Honeypolis using Human Skin Model

  • Woo, SoonOk;Han, Sangmi;Hong, Inpyo;Kim, Sung-kuk
    • 한국양봉학회지
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    • 제33권4호
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    • pp.277-282
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    • 2018
  • Ethanol extracted propolis (EEP) was mixed with honey (honeypolis) to dissolve well in water and in vitro skin irritation test was conducted. In vitro method is designed to predict and classify the skin irritation potential of a chemical by assessment of its effect on $EpiDerm^{TM}$, a reconstituted three-dimensional human epidermis model. Cytotoxicity is expressed as the reduction of mitochondrial dehydrogenase activity measured by formazan production from MTT after a 60 min exposure period. In this study under the given conditions honeypolis showed no irritant effects. Honeypolis meets acceptance criteria if: mean absolute OD 570 nm of the three negative control tissues is ${\geq}0.8$ and ${\leq}2.8$, mean relative tissue viability of the three positive control tissues is ${\leq}20%$, standard deviation of relative tissue viability obtained from each three concurrently tested tissues is ${\leq}18%$. Honeypolis is therefore classified as "non-irritant" in accordance with UN GHS "No Category".

Effects of astaxanthin on antioxidant capacity of golden pompano (Trachinotus ovatus) in vivo and in vitro

  • Xie, Jia-jun;Chen, Xu;Niu, Jin;Wang, Jun;Wang, Yun;Liu, Qiang-qiang
    • Fisheries and Aquatic Sciences
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    • 제20권4호
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    • pp.6.1-6.8
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    • 2017
  • The objective of this research was to study the effect of astaxanthin (AST) on growth performance and antioxidant capacity in golden pompano (Trachinotus ovatus) both in vivo and in vitro. In the in vivo study, two diets were formulated with or without astaxanthin supplementation (D1 and D2; 0 and 200 mg/kg) to feed fish for 6 weeks. In the in vitro study, cells from hepatopancreas of golden pompano were isolated and four treatments with or without astaxanthin and $H_2O_2$ supplementation were applied (control group: without both astaxanthin and $H_2O_2$ treated; $H_2O_2$ group: just with $H_2O_2$ treated; $H_2O_2$ + AST group: with both astaxanthin and $H_2O_2$treated; AST group: just with AST treated). Results of the in vivo study showed that weight gain (WG) and special growth rate (SGR) significantly increased with astaxanthin supplemented (P < 0.05). Feed conversion ratio (FCR) of fish fed D2 diet was significantly lower than that of fish fed D1 diet (P < 0.05). Hepatic total antioxidant capacity (T-AOC) and the reduced glutathione (GSH) of golden pompano fed D2 diet were significant higher than those of fish fed D1 diet (P < 0.05). Superoxide dismutase (SOD) was significantly declined as astaxanthin was supplemented (P < 0.05). Results of the in vitro study showed that the cell viability of $H_2O_2$ group was 52.37% compared to the control group, and it was significantly elevated to 84.18% by astaxanthin supplementation ($H_2O_2$ + AST group) (P < 0.05). The total antioxidant capacity (T-AOC) and the reduced glutathione (GSH) of cell were significant decreased by oxidative stress from $H_2O_2$ (P < 0.05), but it could be raised by astaxanthin supplementation ($H_2O_2$ vs $H_2O_2$ + AST), and the malondialdehyde (MDA) was significant higher in $H_2O_2$ group (P < 0.05) and astaxanthin supplementation could alleviate the cells from lipid peroxidation injury. In conclusion, dietary astaxanthin supplementation can improve the growth performance of golden pompano. Moreover, astaxanthin can improve the golden pompano hepatic antioxidant capacity both in vivo and in vitro study by eliminating the reactive oxygen species.

비스에칠헥실옥시페놀메톡시페닐트리아진(BEMT)을 봉입한 고형지질나노입자(Solid Lipid Nano-particle)의 화장품 응용 (Cosmetic Application of Bis-ethylhexyloxyphenolmethoxyphenyltriazine (BEMT) Loaded Solid Lipid Nano-particle (SLN))

  • 이근수;이동환;표형배;최태부
    • 대한화장품학회지
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    • 제33권4호
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    • pp.219-225
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    • 2007
  • 비스에칠헥실옥시페놀메톡시페닐트리아진(Bis-ethylhexyloxyphenolmeth oxyphenyltrizine; BEMT)은 식품의약품안전청 고시 기능성 원료로 자외선 차단 제품에 널리 사용되는 UVA와 UVB의 화학적 자외선 흡수제이다. 그러나 BEMT는 실제 적용에 있어 여러 가지 결점이 있어 사용이 제한되고 있다. 본 연구의 목적은 BEMT가 적용된 고형지질나노입자(BEMT- SLN)의 자외선차단제품 응용에 있다. 제조된 고형지질나노입자의 입도는 약 330 nm, 봉입율은 93.3 %, 결정화지표는 4.3 %였다. In vitro 방출 및 투과 실험 결과에서, BEMT는 SLN보다 O/W 에멀젼이 대체로 높았다. In vivo 실험에서 SLN의 BEMT 방출비는 80 % 감소하였다. 또한 in vitro UV 방어 효과 실험에서 SLN이 적용된 처방의 자외선방어지수(SPF) 값은 약 2.5배 증가하였다. 결국 SLN은 BEMT를 효과적으로 봉입하고 있었으며, 자외선 차단 상승 효과를 나타낸다.

약물의 in vitro 투과 실험을 위한 사람의 비강점막상피세포 단층막의 일차배양 (Primary Culture of Human Nasal Epithelial Cell Monolayer for In Vitro Drug Transport Studies)

  • 유진욱;김유선;이민기;노환중;이치호;김대덕
    • Journal of Pharmaceutical Investigation
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    • 제32권1호
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    • pp.21-26
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    • 2002
  • The primary culture of human nasal epithelial cell monolayer was performed on a Transwell. The effect of various factors on the tight junction formation was observed in order to develop an in vitro experimental system for nasal transport studies. Human nasal epithelial cells, collected from human normal inferior turbinates, were plated onto diverse inserts. After 4 days, media of the apical surface was removed for air-liquid interface (ALI) culture. Morphological characteristics was observed by transmission electron microscopy (TEM). A polyester membrane of $0.4\;{\mu}m$ pore size was determined as the most effective insert based on the change in the transepithelial electric resistance (TEER) value as well as the $^{14}C-mannitol$ transport study. The ALI method was effective in developing the tight junction as observed in the further increase in the TEER value and reduction in the permeability coefficient $(P_{app})$ of $^{14}C-mannitol$ transport. Results of the transport study of a model drug, budesonide, showed that the primary culture system developed in this study could be further developed and applied for in vitro nasal transport studies.

Effects of Sodium Nitroprusside and Nitric Oxide on In Vitro Maturation of Canine Oocytes

  • Park, Ji-Hoon;Lee, Bong-Koo;Chung, Young-Ho;Rhee, Man-Hee;Kim, S.K.
    • Reproductive and Developmental Biology
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    • 제35권4호
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    • pp.469-473
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    • 2011
  • These study was carried out to investigate the effects of the supplementation with sodium nitroprusside (SN) and nitric oxide (NO) of canine oocytes on IVM rates. Oocytes were incubated in TCM-199 supplement with at 0.03~0.10 mM SN and 0.3~1.0 mM NO for 48 hrs. Oocytes were transferred to 50 ul drops of maturation medium covered mineral oil and cultured in a $CO_2$ incubator (5% $CO_2$, 95% air, $38^{\circ}C$). The in vitro maturation rate of oocytes cultured for 48 hrs in TCM-199 medium supplement with 0.03, 0.05, 0.07, 0.10 mM SN were $25.9{\pm}3.5%$, $36.4{\pm}3.2%$, $33.3{\pm}3.5%$, $28.8{\m}3.2%$, respectively. The in vitro maturation rate of oocytes cultured for 48 hrs in TCM-199 medium supplement with 0.03~0.07 mM SN were significantly increased compare to the control ($26.0{\pm}2.2%$). The in vitro maturation rates of oocytes cultured for 48 hrs in TCM-199 medium supplement with 0.3, 0.5, 0.7, 1.0 mM NO were $28.0{\pm}4.2%$, $36.5{\pm}3.6%$, $30.0{\pm}3.8%$, $19.2{\pm}3.5%$, respectively. The in vitro maturation rate of oocytes in TCM-199 medium supplemented with 0.3 and 0.5 mM NO were significantly increased compare to the control ($26.0{\pm}2.2%$). The in vitro maturation rates of oocytes cultured for 12~48 hrs in TCM-199 medium supplement with 0.05 mM SN were $26.0{\pm}3.2%$, $28.0{\pm}3.4%$, $38.0{\pm}3.2%$, respectively. The in vitro maturation rate of oocytes cultured for 12~48 hrs in TCM-199 medium supplement with 0.5 mM NO were $22.0{\pm}3.0%$, $30.0{\pm}3.8%$, $36.0{\pm}4.2%$, respectively. These result was significantly increased compare to the control.

The EphA8 Receptor Phosphorylates and Activates Low Molecular Weight Phosphotyrosine Protein Phosphatase in Vitro

  • Park, Soo-Chul
    • BMB Reports
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    • 제36권3호
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    • pp.288-293
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    • 2003
  • Low molecular weight phosphotyrosine protein phosphatase (LMW-PTP) has been implicated in modulating the EphB1-mediated signaling pathway. In this study, we demonstrated that the EphA8 receptor phosphorylates LMW-PTP in vitro. In addition, we discovered that mixing these two proteins leads to EphA8 dephosphorylation in the absence of phosphatase inhibitors. Finally, we demonstrated that LMW-PTP, modified by the EphA8 autokinase activity, possesses enhanced catalytic activity in vitro. These results suggest that LMW-PTP may also participate in a feedback-control mechanism of the EphA8 receptor autokinase activity in vivo.

Preliminary Study on the Antisnake Venom Activity of Alcoholic Root Extract of Clerodendrum viscosum (Vent.) in Naja naja Venom

  • Lobo, Richard;Punitha, I.S.R.;Rajendran, K.;Shirwaikar, Arun;Shirwaikar, Annie
    • Natural Product Sciences
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    • 제12권3호
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    • pp.153-156
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    • 2006
  • The antisnake venom activity of Clerodendrum viscosum Vent. (Fam. Verbenaceae), a plant traditionally used in India for the treatment of snake bite was evaluated by in vitro and in vivo methods. While in vitro studies were performed using human blood, in vivo studies were carried out using mice administered three different i.p doses of the extract, 5 min before the administration of Naja naja snake venom. The results of the in vitro studies showed that the extract probably interacts with but does not stabilize membrane protein. In the in vivo studies the extract showed significant antisnake venom activity, which may be attributed to its possible interference with the acetylcholine receptor sites. Hence the present investigation justifies the traditional use of Clerodendrum viscosum (C. viscosum) as antisnake venom.

Cumulus and granulosa cell biomarkers: a good predictor for successful oocyte and embryo developmental competence in human in vitro fertilization

  • Yu, Eun Jeong;Lyu, Sang Woo
    • Journal of Genetic Medicine
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    • 제18권1호
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    • pp.1-7
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    • 2021
  • The oocyte quality is of great importance in infertility as it reflects the follicle developmental potential and further affects the embryo development, clinical pregnancy outcomes. The analysis of gene expression in somatic cells is an important study to better clinical in vitro fertilization (IVF) outcomes in embryo selection reflecting the appropriate communication between the oocyte and somatic cells. Specifically, somatic cell transcriptomic technology can help assess biomarkers of oocyte and embryo ability. The present article aims to overview the basic aspect of folliculogenesis and review studies involving changes in candidate gene expression of cumulus or granulosa cell related to clinical outcomes in human IVF.