• Title/Summary/Keyword: stem flow

Search Result 230, Processing Time 0.03 seconds

Multiple Dissecting Aneurysms of the PICA Trunk - Case Report - (다발성 후하소뇌동맥 해리성 동맥류 - 증 례 보 고 -)

  • Kim, Jong Tae;Kim, Han Kyu
    • Journal of Korean Neurosurgical Society
    • /
    • v.30 no.1
    • /
    • pp.66-72
    • /
    • 2001
  • Apatient with multiple dissecting aneurysms of a posterior inferior cerebellar artery trunk who presented with SAH is reported. A 58-year-old woman presented with sudden occipital headache, dizziness and vomiting. The intial vertebral angiography revealed a suspicious pearl and string sign at the proximal posterior inferior cerebellar artery(PICA) segment. After 2 weeks, follow up angiography showed a progression of the proximal PICA dissection and newly developed dissecting aneurysm of the distal PICA segment. A far lateral suboccipital transcondylar appoach confirmed two dissecting aneurysms at distant sites of the PICA trunk. The dissection segments were wrapped with muslin wrap, which preserved the flow through the PICA and brain stem perforators. The angiographys at 3 weeks and 6 months after operation revealed serial disappearance of the dissecting aneurysms which is distal to proximal. The diagnosis, course and treatment of the dissecting aneurysms of the PICA are discussed with literature review.

  • PDF

Novel Reproductive Techniques in Swine Production - A Review

  • Okere, C.;Nelson, L.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.3
    • /
    • pp.445-452
    • /
    • 2002
  • The main objective of modern reproductive technologies in pig reproduction is to increase reproductive efficiency and rates of genetic improvement. They also offer potential for greatly extending the multiplication and transport of genetic materials and the conservation of unique genetic resources in reasonably available forms for possible future use. The development and refinement of these technologies is concentrating on gamete and embryo collection, sorting and preservation, in vitro production of embryos, culturing, manipulation of embryos (splitting, nuclear transfer, production of chimeras, establishment embryo stem cells, and gene transfer) and embryo transfer. Also, the development of these novel technologies is facilitated by modern equipment for ultrasonography, microscopy, cryopreservation, endoscopy, and flow cytometry, microinjectiors, micromanipulators and centrifugation. The real impact on herd productivity will come from combining new reproductive techniques with powerful DNA technologies. The new reproductive techniques will allow a rapid turnover of generations, whereas the DNA technology can provide selection, which does not need phenotypic information when the selection decisions are made.

Determination of Hyperin in Acanthopanax senticosus and A. sessiliflorus by HPLC (HPLC에 의한 가시오가피 및 오가피 중 Hyperin의 정량)

  • 이상현;정하숙;신국현;김박광
    • YAKHAK HOEJI
    • /
    • v.48 no.4
    • /
    • pp.231-235
    • /
    • 2004
  • A new high performance liquid chromatographic method was applied for the determination of hyperin in Acanthopanax senticosus and A sessiliflorus. The stationary phase used was $\beta$-Bondapak $C_{18}$ reverse-phase column and a mobile phase program was a gradient of acetonitrile and distilled water at a flow rate of 1.0 ml/min. Hyperin was detected at 210 nm, and the analysis was successfully carried out within 20 min. Hyperin was detected in the one year-grown and two years-grown stem of A senticosus (0.47 and 0.13 mg/g, respectively) and A sessiliflorus (0.14 and 0.03 mg/g, respectively). Hyperin was detected in the main and branch root of A sessiliflorus (0.30 and 0.09 mg/g, respectively). But there is no detection of hyperin in the main and branch root of A senticosus.

Preparation, Characterization, and Catalytic Applications of Graphene-palladium Nanocomposites

  • Hong, Yeong-Guk;Yu, Se-Hui;Park, Jun-Beom
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2012.02a
    • /
    • pp.262-262
    • /
    • 2012
  • Modifications of graphenes have been studied for catalytic applications due to their advantages such as high surface area, conductivity and thermal stability. In this research, individual graphene oxide (GO) sheets were exfoliated from graphite using Hummers and Offeman method. Pd nano-particles were deposited on the GO surface using Pd2+ ion exchange where hydroxyl groups on the GO act as nucleation sites of Pd nanoparticles and their dispersions. The thermal treatments of the Pd-GO in H2 flow produced Pd-Graphene nanocomposites. Their catalytic performances in Sonogashira reaction were investigated. Morphological and chemical structures of the GO, Pd-GO, and Pd-Graphene were investigated using FT-IR, XRD, TEM, STEM, and XPS. The catalytic performances have been investigated using microwave reactor.

  • PDF

Nanostructured Polymer Electrolytes for Li-Batteries and Fuel Cells

  • Park, Mun-Jeong
    • Proceedings of the Materials Research Society of Korea Conference
    • /
    • 2012.05a
    • /
    • pp.71.2-71.2
    • /
    • 2012
  • There are rising demands for developing more efficient energy materials to stem the depletion of fossil fuels, which have prompted significant research efforts on proton exchange fuel cells (PEFCs) and lithium ion batteries (LIBs). To date, both PEFCs and LIBs are being widely developed to power small electronics, however, their utilization to medium-large sized electric power resources such as vehicle and stationary energy storage systems still appears distant. These technologies increasingly rely upon polymer electrolyte membranes (PEMs) that transport ions from the anode to the cathode to balance the flow of electrons in an external circuit, and therefore play a central role in determining the efficiency of the devices; as ion transport is a kinetic bottleneck compared to electrical conductivity, enormous efforts have been devoted to improving the transport properties of PEMs. In present study, we carried out an in-depth analysis of the morphology effects on transport properties of PEMs. How parameters such as self-assembled nanostructures, domain sizes, and domain orientations affect conductivities of PEMs will be presented.

  • PDF

Potential How Analysis for a Hull with the Transom Stern (트랜섬 선미를 가지는 선형의 포텐셜 유동해석)

  • 최희종;전호환
    • Journal of Ocean Engineering and Technology
    • /
    • v.15 no.1
    • /
    • pp.1-6
    • /
    • 2001
  • This study focuses on the potential flow analysis for a hull with the transom stern. The method is based on a low order panel method. The Kelvin type free-surface boundary condition which is known to better fit experimental data for a high speed is applied. To treat a dry transom stern effect a special treatment for the free-surface boundary condition is adopted at the free-surface region after the transom stern. Trim and sinkage, which are important in high speed ships, are considered by an iterative method. Pressure and momentum approaches are used to calculate the wave resistance. Numerical calculations are performed for Athena hull and these results are compared with the experimental data and also other computational results.

  • PDF

Hematopoiesis Activity of Sambucus javanica on Chloramphenicol-induced Aplastic Anemia Mouse Model

  • Putra, Wira Eka;Rifa'i, Muhaimin
    • Natural Product Sciences
    • /
    • v.25 no.1
    • /
    • pp.59-63
    • /
    • 2019
  • Hematopoiesis has a pivotal role in the maintenance of body homeostasis. Ironically, several hematological disorder caused by chemicals, drugs, and other environmental factors lead to severe bone marrow failure. Current treatments like stem cell transplantation and immunosuppression remain ineffective to ameliorate this diseases. Therefore, a newtreatment to overcome this entity is necessary, one of them by promoting the usage of medicinal plants. Thus, this study aimed to evaluate the hematopoiesis potency of S. javanica berries and leaves extracts in chloramphenicol (CMP)-induced aplastic anemia mice model. In this present study, several types of blood progenitor cell such as $TER-119^+VLA-4^+$ erythrocytes lineage, $Gr-1^+$ granulocytes, and $B220^+$ B-cell progenitor cells were evaluated by flow cytometry analysis. Accordingly, we revealed that S. javanica berries and leaves extracts significantly promoted $TER-119^+VLA-4^+$ erythrocytes lineage and $Gr-1^+$ granulocytes after exposed by CMP. Thus, these results suggested that S. javanica berries and leaves extracts might have hematopoiesis activity in CMP-induced aplastic anemia mice model.

A Study of Sap Movement in Mulberry (Morus species) Stem in Spring (뽕나무의 춘기 수액이동에 관한 연구)

  • Lee, Won-Ju;Min, Yeong-Sang;Choe, Yeong-Cheol
    • Journal of Sericultural and Entomological Science
    • /
    • v.32 no.2
    • /
    • pp.85-88
    • /
    • 1990
  • Sap flow in mulberry (Morus species) trees was observed for one month from mid-March in 1981, 1982 and 1990. The results were : 1. Sap flow at 20cm soil depth occurred on April 8, 1981 at 10.1$^{\circ}C$, on April 2, 1982 at 8.3$^{\circ}C$ and March 25, 1990 at 8.7$^{\circ}C$. The data showed a range of 1.8$^{\circ}C$ and 15 days. 2. Water content of the wood decreased with decreasing soil temperature under 8$^{\circ}C$, whereas water content of the cortex remained constant or increased. Water may move form wood to cortex when it was insufficient in cortex. 3. Sap flow at 20cm soil depth occurred when accumulated soil temperature after March 1 about 180$^{\circ}C$.

  • PDF

Apoptosis-Inducing Activity of Galloylglucoses from Juglans mandshurica in Human Promyeloid Leukemic HL-60 Cells

  • Min, Byung-Sun;Kwon, Ok-Kyoung;Park, Bo-Young;Kim, Young-Ho;Hattori, Masao;Joung, Hyouk;Lee, Hyeong-Kyu
    • Natural Product Sciences
    • /
    • v.10 no.1
    • /
    • pp.48-53
    • /
    • 2004
  • Two galloyl monosaccharides, 1,2,6-trigalloylglucose (1, TRgG) and 1,2,3,6- tetragalloylglucose (2, TEgG), were isolated from the stem-bark of Juglans mandshurica. Two galloylglucoses showed cytotoxic effects on human promyelocytic leukemia HL-60 cells. In order to elucidate their mechanism of action, we have investigated the flow cytometric analysis after Annexin V-FITC and PI staining, caspase-3 activity, and internucleosomal DNA fragmentation in HL-60 cells. HL-60 cells treated with both compounds 1 and 2 at 150 and $100\;{\mu}M$, respectively, led to a morphological features of apoptosis, such as plasma membrane blebbing and cell shrinkage. TRgG (1) and TEgG (2) increased the percentage of $FITC^+\;and\;FITC^+PI^+$ cells in flow cytometry after Annexin V-FITC and PI staining. The increase of apoptotic cells was preceded by the activation of caspase-3 reported to play a central role in apoptotic process and inducing internucleosomal DNA fragmentation. TEgG (2) showed to have stronger apoptosis inducing activity in HL-60 cell lines as compared with TRgG (1).

T Lymphocyte Subsets and Cytokines in Rats Transplanted with Adipose-Derived Mesenchymal Stem Cells and Acellular Nerve for Repairing the Nerve Defects

  • Jiang, Liang-fu;Chen, Ou;Chu, Ting-gang;Ding, Jian;Yu, Qing
    • Journal of Korean Neurosurgical Society
    • /
    • v.58 no.2
    • /
    • pp.101-106
    • /
    • 2015
  • Objective : The aim of this study was to explore the immunity in rats transplanted with adipose-derived mesenchymal stem cells (ADSCs) and acellular nerve (ACN) for repairing sciatic nerve defects. Methods : ADSCs were isolated from the adipose tissues of Wistar rats. Sprague-Dawley rats were used to establish a sciatic nerve defect model and then divided into four groups, according to the following methods : Group A, allogenic nerve graft; Group B, allograft with ACN; Group C, allograft ADSCs+ACN, and Group D, nerve autograft. Results : At the day before transplantation and 3, 7, 14, and 28 days after transplantation, orbital venous blood of the Sprague-Dawley rats in each group was collected to detect the proportion of $CD3^+$, $CD4^+$, and $CD8^+$ subsets using flow cytometry and to determine the serum concentration of interleukin-2 (IL-2), tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) and $interferon-{\gamma}$ ($IFN-{\gamma}$) using enzyme-linked immunosorbent assay (ELISA). At each postoperative time point, the proportion of $CD3^+$, $CD4^+$, and $CD8^+$ subsets and the serum concentration of IL-2, $TNF-{\alpha}$, and $IFN-{\gamma}$ in group C were all near to those in group B and group D, in which no statistically significant difference was observed. As compared with group A, the proportion of $CD3^+$, $CD4^+$, and $CD8^+$ subsets and the serum concentration of IL-2, $TNF-{\alpha}$, and $IFN-{\gamma}$ were significantly reduced in group C (p<0.05). Conclusion : The artificial nerve established with ADSCs and ACN has no obvious allograft rejection for repairing rat nerve defects.