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1

Vero cell assay for rapid detection of Clostridium perfringens enterotoxin.  

PubMed Central

A rapid assay which measured the biological activity of Clostridium perfringens enterotoxin was developed. The method involved the rapid killing of Vero cells by enterotoxin produced by C. perfringens grown in Duncan and Strong sporulation medium. Serial dilutions of toxin were added to Vero cells either in suspension or grown as monolayers in wells of a 96-well cell tissue culture cluster plate. Vital staining of Vero cells with neutral red, followed by extraction of the dye, allowed toxin levels to be determined either visually or by optical density measurements with a micro-ELISA M580 computer program. The toxin produced was confirmed as different from the Vero toxin of Escherichia coli and the alpha and theta toxins of C. perfringens.

Mahony, D E; Gilliatt, E; Dawson, S; Stockdale, E; Lee, S H

1989-01-01

2

Arenoviruses in Vero Cells: Ultrastructural Studies  

PubMed Central

Thin-section electron microscopy was carried out on Vero green monkey kidney cell cultures infected with some viruses of the newly constituted arenovirus group. Junin, Machupo, Amapari, Pichinde, Parana, Tamiami, and Latino viruses were morphologically identical and indistinguishable from lymphocytic choriomeningitis virus, the prototype virus of the group. Virus particles were round, oval, or pleomorphic, 60 to 280 nm in diameter, and matured via budding from plasma membranes. Most characteristically, particles contained various amounts of homogeneous, 20- to 25-nm, dense granules; these granules in large masses also formed distinctive intracytoplasmic inclusions. In negative-contrast preparations from infected Vero cell culture supernatant fluids, several of the viruses appeared as pleomorphic membrane-bound forms with rather pronounced surface projections. Most particles were between 90 and 220 nm in diameter, although some reached 350 nm in their longest dimension. Internal structure was not resolved by negative-contrast electron microscopy. All observations supported the current delineation of a distinct arenovirus group. Images

Murphy, Frederick A.; Webb, Patricia A.; Johnson, Karl M.; Whitfield, Sylvia G.; Chappell, W. Adrian

1970-01-01

3

Arenoviruses in Vero cells: ultrastructural studies.  

PubMed

Thin-section electron microscopy was carried out on Vero green monkey kidney cell cultures infected with some viruses of the newly constituted arenovirus group. Junin, Machupo, Amapari, Pichinde, Parana, Tamiami, and Latino viruses were morphologically identical and indistinguishable from lymphocytic choriomeningitis virus, the prototype virus of the group. Virus particles were round, oval, or pleomorphic, 60 to 280 nm in diameter, and matured via budding from plasma membranes. Most characteristically, particles contained various amounts of homogeneous, 20- to 25-nm, dense granules; these granules in large masses also formed distinctive intracytoplasmic inclusions. In negative-contrast preparations from infected Vero cell culture supernatant fluids, several of the viruses appeared as pleomorphic membrane-bound forms with rather pronounced surface projections. Most particles were between 90 and 220 nm in diameter, although some reached 350 nm in their longest dimension. Internal structure was not resolved by negative-contrast electron microscopy. All observations supported the current delineation of a distinct arenovirus group. PMID:5497898

Murphy, F A; Webb, P A; Johnson, K M; Whitfield, S G; Chappell, W A

1970-10-01

4

Oxidative Stress in Vero Cells Infected with Vesicular Stomatitis Virus  

Microsoft Academic Search

Viral-induced apoptosis might be mediated by oxidative stress. It has already been described that cell death in vesicular stomatitis virus (VSV)-infected cells occurs by apoptosis. In this study, oxidative stress parameters present in VSV-infected Vero cells were analyzed. Lipid peroxides (LP) were evaluated in cellular extracts and expressed as thiobarbituric acid-reactive substances. LP levels exhibited a rise at different times

Diego A. Riva; María C. Ríos de Molina; Iara Rocchetta; Elizabeth Gerhardt; Félix C. Coulombié; Susana E. Mersich

2006-01-01

5

A Vero cell method for potency testing of diphtheria vaccines.  

PubMed

A collaborative study on the evaluation of an alternative functional assay to the Ph. Eur. in vivo challenge procedure for potency determination of diphtheria toxoid vaccines was initiated in January 2001. This study is an extension of the collaborative study for the validation of serological methods for potency testing of tetanus toxoid vaccines for human use. The primary aim was to examine whether a Vero cell assay is a valid alternative to the Ph. Eur. in vivo challenge methods for potency determination of the diphtheria toxoid component of combined vaccines. The study also investigated whether sera from the same immunised guinea pigs can be used for potency determination of both the diphtheria and the tetanus toxoid components. The project was divided into three parts. In part I, summarised in this publication, the operating procedures for the methods and the optimal vaccine dilutions for the immunisation of guinea pigs were established. From the results of the part I study, performed in two laboratories, the correlation co-efficients between the Vero cell method and the challenge assay were considered satisfactory to warrant continuing with the next phase. Comparable diphtheria potency estimates were obtained in the two assays for four vaccines of different activities (range ca. 20-200 IU/ml). The study also provided preliminary information that sera from the same guinea pigs may also be used for potency determination of both diphtheria and tetanus toxoid components of vaccines by ELISA. PMID:12678233

Winsnes, R; Sesardic, D; Daas, A; Rigsby, P

2002-01-01

6

Receptor-binding properties of modern human influenza viruses primarily isolated in Vero and MDCK cells and chicken embryonated eggs  

Microsoft Academic Search

To study the receptor specificity of modern human influenza H1N1 and H3N2 viruses, the analogs of natural receptors, namely sialyloligosaccharides conjugated with high molecular weight (about 1500 kDa) polyacrylamide as biotinylated and label-free probes, have been used. Viruses isolated from clinical specimens were grown in African green monkey kidney (Vero) or Madin–Darby canine kidney (MDCK) cells and chicken embryonated eggs.

Larisa Mochalova; Alexandra Gambaryan; Julia Romanova; Alexander Tuzikov; Alexander Chinarev; Dietmar Katinger; Herman Katinger; Andrej Egorov; Nicolai Bovin

2003-01-01

7

Development of a Vero cell DNA reference standard for residual DNA measurement in China.  

PubMed

This collaborative study developed a Vero cell DNA reference for standardizing dot blot hybridization, an assay widely employed to measure residual DNA contents of viral vaccines prepared with Vero cells. High purity of Vero cell DNA was extracted and characterized by Hind III enzyme digestion and DNA sequencing. Then, with a cooperative calibration, the concentration of Vero cell DNA reference bulk solution was determined (64.0 ± 1.9 ?g/mL, OD 260/OD 280 = 1.87) and diluted (40 ng/mL) with Tris-EDTA buffer containing bovine serum albumin as freeze-dried excipients. With industrial filling apparatus, the diluted bulk was loaded into ampoules (0.5 mL each) which were heat sealed after nitrogen filling. Finally, a collaborative study showed that the Vero cell DNA reference could reach a sensitivity of 1 to 5 pg/dot and maintained good stability after accelerated destruction test. The successful establishment of the Vero cell DNA quantitative reference will facilitate the standardization of dot blot hybridization for testing residual host cell DNA. PMID:23291952

Cao, Shouchun; Dong, Guanmu; Tang, Jianrong; Li, Jia; Liu, Jinghua; Shi, Leitai; Li, Changgui; Wang, Junzhi

2013-01-04

8

The spike protein of severe acute respiratory syndrome (SARS) is cleaved in virus infected Vero-E6 cells.  

PubMed

Spike protein is one of the major structural proteins of severe acute respiratory syndrome-coronavirus. It is essential for the interaction of the virons with host cell receptors and subsequent fusion of the viral envelop with host cell membrane to allow infection. Some spike proteins of coronavirus, such as MHV, HCoV-OC43, AIBV and BcoV, are proteolytically cleaved into two subunits, S1 and S2. In contrast, TGV, FIPV and HCoV-229E are not. Many studies have shown that the cleavage of spike protein seriously affects its function. In order to investigate the maturation and proteolytic processing of the S protein of SARS CoV, we generated S1 and S2 subunit specific antibodies (Abs) as well as N, E and 3CL protein-specific Abs. Our results showed that the antibodies could efficiently and specifically bind to their corresponding proteins from E.coli expressed or lysate of SARS-CoV infected Vero-E6 cells by Western blot analysis. Furthermore, the anti-S1 and S2 Abs were proved to be capable of binding to SARS CoV under electron microscope observation. When S2 Ab was used to perform immune precipitation with lysate of SARS-CoV infected cells, a cleaved S2 fragment was detected with S2-specific mAb by Western blot analysis. The data demonstrated that the cleavage of S protein was observed in the lysate, indicating that proteolytic processing of S protein is present in host cells. PMID:15450134

Wu, Xiao Dong; Shang, Bo; Yang, Rui Fu; Yu, Hao; Ma, Zhi Hai; Shen, Xu; Ji, Yong Yong; Lin, Ying; Wu, Ya Di; Lin, Guo Mei; Tian, Lin; Gan, Xiao Qing; Yang, Sheng; Jiang, Wei Hong; Dai, Er Hei; Wang, Xiao Yi; Jiang, Hua Liang; Xie, You Hua; Zhu, Xue Liang; Pei, Gang; Li, Lin; Wu, Jia Rui; Sun, Bing

2004-10-01

9

Pre-clinical development of cell culture (Vero)-derived H5N1 pandemic vaccines.  

PubMed

The rapid spread of avian influenza (H5N1) and its transmission to humans has raised the possibility of an imminent pandemic and concerns over the ability of standard influenza vaccine production methods to supply sufficient amounts of an effective vaccine. We report here on a robust and flexible strategy which uses wild-type virus grown in a continuous cell culture (Vero) system to produce an inactivated whole virus vaccine. Candidate vaccines based on clade 1 and clade 2 influenza H5N1 strains, produced at a variety of manufacturing scales, were demonstrated to be highly immunogenic in animal models without the need for adjuvant. The vaccines induce cross-neutralising antibodies and are protective in a mouse challenge model not only against the homologous virus but against other H5N1 strains, including those from other clades. These data indicate that cell culture-grown, whole virus vaccines, based on the wild-type virus, allow the rapid high-yield production of a candidate pandemic vaccine. PMID:18953724

Howard, M Keith; Kistner, Otfried; Barrett, P Noel

2008-05-01

10

Development of a mammalian cell (Vero) derived candidate influenza virus vaccine  

Microsoft Academic Search

Influenza vaccine production is dependent on the availability of embryonated hen eggs for virus growth. This is an extremely cumbersome system with many disadvantages with respect to selection of virus variants and presence of adventitious viruses. We have developed an alternative cell culture system which allows rapid production of large volumes of vaccine. The World Health Organisation (WHO) approved Vero

O Kistner; P. N. Barrett; W. Mundt; M. Reiter; S. Schober-Bendixen; F. Dorner

1998-01-01

11

Possible involvement of receptors in the entry of Kunjin virus into Vero cells  

Microsoft Academic Search

Summary The results obtained from electron microscopy, adsorbed and internalised virus assays and immunofluorescence studies supported that the most likely mode of entry of Kunjin virus into Vero cells was by receptor-mediated endocytosis. This was deduced indirectly from the time sequence of events that occurred. Electron microscopy revealed that endocytosis of the virus through coated vesicles had occurred. The adsorbed

Mah Lee Ng; Lionel C. L. Lau

1988-01-01

12

Preparation and evaluation of Vero-cell infectious bursal disease vaccine in Pakistan  

Microsoft Academic Search

The present work was carried out to develop an effective vaccine to control infectious bursal disease (IBD). The very virulent infectious bursal disease virus (vvIBDV) was adapted to grow in Vero-cell line after three serial passages. The virus was then attenuated by further serial passages and pathogenicity of different passages was determined in broiler chicks free from antibodies against IBDV.

Muhammad Hidayat Rasool; Iftikhar Hussain

2006-01-01

13

Rose bengal inhibits herpes simplex virus replication in vero and human corneal epithelial cells in vitro.  

PubMed

Rose bengal dye is thought to highlight corneal lesions induced by herpes simplex virus type 1 (HSV-1) by virtue of its binding to dead or dying HSV-1-infected epithelial cells. However, whether rose bengal binds specifically to damaged versus normal corneal epithelial cells is unclear. To determine the binding properties of rose bengal, the authors compared binding of the dye to HSV-1-infected and uninfected cells, determined the cellular binding sites of the dye, and investigated the effects of rose bengal on HSV-1 replication in dye-treated cells in vitro. Spectrophotometric analysis revealed that uninfected and infected Vero cells bound equivalent amounts of dye at several times post inoculation, indicating that rose bengal does not preferentially bind to HSV-1-infected cells. By light microscopy, rose bengal was found to bind to the cell nuclei and perinuclear region of human corneal epithelial cells (HCEC) and Vero cells. Pretreatment of Vero and HCEC with different concentrations of rose bengal and exposure to 148 microW/cm2 of white light for 2 min reduced the ability of both cell types to support HSV-1 replication. Vero cells, in the absence of rose bengal, supported HSV-1 replication, whereas pre-treatment with 0.05% rose bengal reduced the yield of HSV-1 by 99.99% (P less than 0.000001) and 1% rose bengal completely prevented HSV replication. HCEC supported HSV-1 replication in the absence of rose bengal, but pre-treatment with 1% or 0.05% rose bengal completely prevented HSV-1 replication (P less than 0.000001).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1321799

Chodosh, J; Banks, M C; Stroop, W G

1992-07-01

14

Vero cell platform in vaccine production: moving towards cell culture-based viral vaccines.  

PubMed

The development of cell culture systems for virus propagation has led to major advances in virus vaccine development. Primary and diploid cell culture systems are now being replaced by the use of continuous cell lines (CCLs). These substrates are gaining increasing acceptance from regulatory authorities as improved screening technologies remove fears regarding their potential oncogenic properties. The Vero cell line is the most widely accepted CCL by regulatory authorities and has been used for over 30 years for the production of polio and rabies virus vaccines. The recent licensure of a Vero cell-derived live virus vaccine (ACAM2000, smallpox vaccine) has coincided with an explosion in the development of a range of new viral vaccines, ranging from live-attenuated pediatric vaccines against rotavirus infections to inactivated whole-virus vaccines against H5N1 pandemic influenza. These developments have illustrated the value of this cell culture platform in the rapid development of vaccines against a range of virus diseases. PMID:19397417

Barrett, P Noel; Mundt, Wolfgang; Kistner, Otfried; Howard, M Keith

2009-05-01

15

Oral efficacy of Vero cell attenuated porcine epidemic diarrhea virus DR13 strain  

Microsoft Academic Search

A Vero cell attenuated porcine epidemic diarrhea virus (PEDV) strain, DR13, was distinguished from wild-type PEDV using restric- tion enzyme fragment length polymorphism (RFLP). Cell attenuated DR13 was orally or intramuscularly (IM) administered to late-term pregnant sows, and mortality resulting from the highly virulent PEDV challenge was investigated in passively immunized suckling piglets of the two different groups. The mortality

D. S. Song; J. S. Oh; B. K. Kang; J. S. Yang; H. J. Moon; H. S. Yoo; Y. S. Jang; B. K. Park

2006-01-01

16

Oral efficacy of Vero cell attenuated porcine epidemic diarrhea virus DR13 strain  

Microsoft Academic Search

A Vero cell attenuated porcine epidemic diarrhea virus (PEDV) strain, DR13, was distinguished from wild-type PEDV using restriction enzyme fragment length polymorphism (RFLP). Cell attenuated DR13 was orally or intramuscularly (IM) administered to late-term pregnant sows, and mortality resulting from the highly virulent PEDV challenge was investigated in passively immunized suckling piglets of the two different groups. The mortality rate

D. S. Song; J. S. Oh; B. K. Kang; J. S. Yang; H. J. Moon; H. S. Yoo; Y. S. Jang; B. K. Park

2007-01-01

17

Formation of varicella-zoster virus antigens in infected Vero cells.  

PubMed

The formation of varicella-zoster (V-Z) virus-associated antigens was studied in V-Z virus-infected Vero cells by means of indirect immunofluorescence. Early antigen (EA) was first detected inside V-Z virus-infected Vero cells 4 to 6 hr after infection, whereas surface membrane antigen (SMA) was expressed on the outer surface of infected cells 2 to 3 hr later than EA, and intranuclear late antigen (LA) was detected several hours later than SMA antigen. EA expression was not inhibited by cytosine arabinoside (Ara-C) treatment, whereas LA formation was completely blocked by Ara-C. The presence of two components of SMA early SMA (ESMA) and late SMA (LSMA), was suggested by this difference in susceptibility to Ara-C. The formation of all viral antigens, EA, SMA, and LA, was blocked by inhibitors of RNA and protein synthesis. PMID:3003545

Takayama, M; Oya, A

1985-01-01

18

Increased response of Vero cells to PHBV matrices treated by plasma.  

PubMed

The copolymers poly(3-hydroxybutyric acid-co-3-hydroxyvaleric acid) (PHBV) are being intensely studied as a tissue engineering substrate. It is known that poly 3-hydroxybutyric acids (PHBs) and their copolymers are quite hydrophobic polyesters. Plasma-surface modification is an effective and economical surface treatment technique for many materials and of growing interest in biomedical engineering. In this study we investigate the advantages of oxygen and nitrogen plasma treatment to modify the PHBV surface to enable the acceleration of Vero cell adhesion and proliferation. PHBV was dissolved in methylene chloride at room temperature. The PHBV membranes were modified by oxygen or nitrogen-plasma treatments using a plasma generator. The membranes were sterilized by UV irradiation for 30 min and placed in 96-well plates. Vero cells were seeded onto the membranes and their proliferation onto the matrices was also determined by cytotoxicity and cell adhesion assay. After 2, 24, 48 and 120 h of incubation, growth of fibroblasts on matrices was observed by scanning electron microscopy (SEM). The analyses of the membranes indicated that the plasma treatment decreased the contact angle and increased the surface roughness; it also changed surface morphology, and consequently, enhanced the hydrophilic behavior of PHBV polymers. SEM analysis of Vero cells adhered to PHBV treated by plasma showed that the modified surface had allowed better cell attachment, spreading and growth than the untreated membrane. This combination of surface treatment and polymer chemistry is a valuable guide to prepare an appropriate surface for tissue engineering application. PMID:17619989

Lucchesi, Carolina; Ferreira, Betina M P; Duek, Eliana A R; Santos, Arnaldo R; Joazeiro, Paulo P

2007-07-10

19

Equine herpes virus type 1 (EHV1) infection induces alterations in the cytoskeleton of Vero cells but not apoptosis  

Microsoft Academic Search

Summary.  ?Effects of infection with two different strains of equine herpes virus type 1 (EHV-1; Piber 178\\/83, Kentucky D) on the cytoskeleton\\u000a of Vero cells were investigated immunohistochemically, and evaluated by confocal laser scanning microscopy. Twenty four hours\\u000a post EHV-1 infection the assembly of the microtubulus system of Vero cells was heavily disturbed. The Golgi region was dispersed\\u000a into vesicles spread

I. Walter; N. Nowotny

1999-01-01

20

Protective effect of zinc chloride against cobalt chloride-induced cytotoxicity on vero cells: preliminary results.  

PubMed

The aim of this study was to investigate the possible time- and dose-dependent cytotoxic effects of cobalt chloride on Vero cells. The cultured cells were incubated with different concentrations of cobalt chloride ranging from 0.5 to 1,000 ?M, and cytotoxicity was determined by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) and resazurin assays. Possible protective effects of vitamin E, coenzyme Q(10), and zinc chloride were also tested in this system. A gradual decrease in cell proliferation was observed at concentrations ~? 200 ?M in incubation periods of 24, 48, 72, and 96 h with MTT assay. Exposure of cells to 500 and 1,000 ?M cobalt chloride caused significant decrease in cell survival. A biphasic survival profile of cells was observed at 1-25 ?M concentration range following 96 h of incubation. With resazurin assay, cytotoxicity profile of CoCl(2) was found comparable to the results of MTT assay, particularly at high concentrations and long incubation periods. Dose-dependent cytotoxicity was noted following exposure of cells to ? 250 ?M of CoCl(2) for 24 h and ? 100 ?M concentrations of CoCl(2) for 48-96 h. Pretreatment of cells with ZnCl(2) for 4 or 24 h provided significant protection against cobalt chloride-induced cytotoxicity when measured with MTT assay. However, vitamin E or coenzyme Q(10) was not protective. CoCl(2) had dose- and time-dependent cytotoxic effects in Vero cells. Preventive effect of ZnCl(2) against CoCl(2)-induced cytotoxicity should be considered in detail to define exact mechanism of toxicity in Vero cells. PMID:22281816

Gürbay, Aylin

2012-01-27

21

Cytotoxicity of methanol extracts of Elaeis guineensis on MCF-7 and Vero cell lines  

PubMed Central

Objective To investigate the cytotoxic effect of Elaeis guineensis methanol extract on MCF-7 and Vero cell. Methods In vitro cytotoxicity was evaluated in by MTT assay. Cell morphological changes were observed by using light microscope. Results The MTT assay indicated that methanol extract of the plant exhibited significant cytotoxic effects on MCF-7. Morphological alteration of the cell lines after exposure with Elaeis guineensis extract were observed under phase contrast microscope in the dose dependent manner. Conclusions The results suggest the probable use of the Elaeis guineensis methanol extract in preparing recipes for cancer-related ailments. Further studies on isolation of metabolites and their in vivo cytotoxicity are under investigation.

Vijayarathna, Soundararajan; Sasidharan, Sreenivasan

2012-01-01

22

Immunofluorescent sites in vero cells infected with the flavivirus Kunjin  

Microsoft Academic Search

Summary The sites of replication and of accumulation of viral macromolecules were examined using fluorescent antibodies to viral products and to cell organelles. Synthesis of envelope protein and its accumulation in a narrow rim around the nucleus were detected at 4 hours post infection; concurrently, a progressive change was observed in the rough endoplasmic reticulum from a fine to a

Mah Lee Ng; J. S. Pedersen; Ban Hock Toh; E. G. Westaway

1983-01-01

23

Intracellular location of Bartonella henselae cocultivated with Vero cells and used for an indirect fluorescent-antibody test.  

PubMed Central

Bartonella henselae, the major causative agent of cat scratch disease, was cocultivated with Vero cells on chamber slides and visualized by indirect immunofluorescence by using a patient serum containing specific antibodies. Confocal microscopy localized the granular B. henselae-specific fluorescence mainly around the nuclei of Vero cells. By transmission electron microscopy, these granules were identified as clusters of multiple intracellular organisms. Fixed slides with the monolayers of Vero cells with intracellular B. henselae were used for an indirect fluorescent-antibody test to investigate the seroprevalence of specific immunoglobulin G in 100 serum samples from blood donors. Seventy-four serum samples were negative; 19, 3, and 4 were positive at dilutions of 1:64, 1:128, and 1:256, respectively. In our population, a serum titer of 1:256 or greater should stimulate further investigations. Moreover, elucidation of the mechanism by which B. henselae enters the cells may help to understand the pathogenesis of cat scratch disease.

Zbinden, R; Hochli, M; Nadal, D

1995-01-01

24

Diphtheria toxin-induced channels in Vero cells selective for monovalent cations  

SciTech Connect

Ion fluxes associated with translocation of diphtheria toxin across the surface membrane of Vero cells were studied. When cells with surface-bound toxin were exposed to low pH to induce toxin entry, the cells became permeable to Na+, K+, H+, choline+, and glucosamine+. There was no increased permeability to Cl-, SO4(-2), glucose, or sucrose, whereas the uptake of /sup 45/Ca2+ was slightly increased. The influx of Ca2+, which appears to be different from that of monovalent cations, was reduced by several inhibitors of anion transport and by verapamil, Mn2+, Co2+, and Ca2+, but not by Mg2+. The toxin-induced fluxes of N+, K+, and protons were inhibited by Cd2+. Cd2+ also protected the cells against intoxication by diphtheria toxin, suggesting that the open cation-selective channel is required for toxin translocation. The involvement of the toxin receptor is discussed.

Sandvig, K.; Olsnes, S.

1988-09-05

25

Vero-cell rabies vaccine produced using serum-free medium.  

PubMed

A new rabies vaccine was developed from Vero cells adhered to microcarriers, cultivated in a bioreactor in serum-free medium and infected with the PV/VERO-Paris rabies virus strain. The viral suspensions were concentrated by tangential filtration, purified by chromatography and inactivated with beta-propiolactone. In immunogenicity studies performed in mice immunized with three doses of the new vaccine (seven batches) and the commercial Verorab and HDCV, mean titers of neutralizing antibodies of 10.3-34.6, 6.54 and 9.36 IU/ml were found, respectively. The vaccine presented stability during 14 months at 2-8 degrees C, 30 days at 37 degrees C and 8 h at 45 degrees C. The use of serum-free medium facilitated the downstream process leading to residual cellular DNA values <22.8 pg per dose of vaccine in all produced batches. The effective immunogenicity induced in mice by this vaccine, the degree of purity of the product, the high antigen yield and the reduction of the cost of the product due to the virus production and purification processes, makes this technology very important for countries where rabies presents a great public health problem. PMID:15530700

Frazatti-Gallina, Neuza M; Mourão-Fuches, Regina M; Paoli, Rosana L; Silva, Maria L N; Miyaki, Cosue; Valentini, Elizabeth J G; Raw, Isaias; Higashi, Hisako G

2004-12-01

26

[Inhibition of the accumulation of the Lassa virus in Vero cells by immune gamma globulin and complement].  

PubMed

Specific inhibition of Lassa virus replication in Vero cells was found to be better achieved with immune gamma globulin in combination with complement than with gamma globulin alone. According to the authors, the inhibitory effect of these preparations is due to the cyto-destructive action of antibodies and complement on the infected cells. PMID:6208692

Vladyko, A S; Rogacheva, T A; Orlova, S V; Votiakov, V I

27

In vitro efficacy of nitro- and bromo-thiazolyl-salicylamide compounds (thiazolides) against Besnoitia besnoiti infection in Vero cells.  

PubMed

Nitazoxanide (NTZ) and its deacetylated metabolite tizoxanide (TIZ) exhibit considerable in vitro activity against Besnoitia besnoiti tachyzoites grown in Vero cells. Real-time-PCR was used to assess B. besnoiti tachyzoite adhesion, invasion, and intracellular proliferation in vitro. A number of NTZ-derivatives, including Rm4822 and Rm4803, were generated, in which the thiazole-ring-associated nitro-group was replaced by a bromo-moiety. We here show that replacement of the nitro-group on the thiazole ring with a bromo (as it occurs in Rm4822) does not impair the efficacy of the drug, but methylation of the salicylate ring at the ortho-position in a bromo-derivative (Rm4803) results in complete abrogation of the antiparasitic activity. Treatment of extracellular B. besnoiti tachyzoites with NTZ has an inhibitory effect on host cell invasion, while treatments with TIZ, Rm4822 do not. TEM demonstrates that the effects of Rm4822 treatment upon the parasites are similar to the damage induced by NTZ. This includes increased vacuolization of the parasite cytoplasm, and loss of the structural integrity of the parasitophorous vacuole and its membrane. Thus, Rm4822, due to the absence of a potentially mutagenic nitro-group, may represent an important potential addition to the anti-parasitic arsenal for food animal production, especially in cattle. PMID:17306057

Cortes, H C E; Mueller, N; Esposito, M; Leitão, A; Naguleswaran, A; Hemphill, A

2007-02-19

28

RNA interference targeting virion core protein ORF095 inhibits Goatpox virus replication in Vero cells  

PubMed Central

Background Goatpox is an economically important disease in goat and sheep-producing areas of the world. Many vaccine strategies developed to control the disease are not yet completely successful. Hairpin expression vectors have been used to induce gene silencing in a large number of studies on viruses. However, none of these studies has been attempted to study GTPV. In the interest of exploiting improved methods to control goat pox, it is participated that RNAi may provide effective protection against GTPV. In this study we show the suppression of Goatpox virus (GTPV) replication via knockdown of virion core protein using RNA interference. Results Four short interfering RNA (siRNA) sequences (siRNA-61, siRNA-70, siRNA-165 and siRNA-296) against a region of GTPV ORF095 were selected. Sense and antisense siRNA-encoding sequences separated by a hairpin loop sequence were designed as short hairpin RNA (shRNA) expression cassettes under the control of a human U6 promoter. ORF095 amplicon was generated using PCR, and then cloned into pEGFP-N1 vector, named as p095/EGFP. p095/EGFP and each of the siRNA expression cassettes (p61, p70, p165 and p296) were co-transfected into BHK-21 cells. Fluorescence detection, flow cytometric analysis, retro transcription PCR (RT-PCR) and real time PCR were used to check the efficiency of RNAi. The results showed that the ORF095-specific siRNA-70 effectively down-regulated the expression of ORF095. When Vero cells were transfected with shRNA expression vectors (p61/GFP, p70/GFP, p165/GFP and p296/GFP) and then infected with GTPV, GTPV-ORF095-70 was found to be the most effective inhibition site in decreasing cytopathic effect (CPE) induced by GTPV. The results presented here indicated that DNA-based siRNA could effectively inhibit the replication of GTPV (approximately 463. 5-fold reduction of viral titers) on Vero cells. Conclusions This study demonstrates that vector-based shRNA methodology can effectively inhibit GTPV replication on Vero cells. Simultaneously, this work represents a strategy for controlling goatpox, potentially facilitating new experimental approaches in the analysis of both viral and cellular gene functions during of GTPV infection.

2012-01-01

29

Adaptation of High-Growth Influenza H5N1 Vaccine Virus in Vero Cells: Implications for Pandemic Preparedness  

PubMed Central

Current egg-based influenza vaccine production technology can't promptly meet the global demand during an influenza pandemic as shown in the 2009 H1N1 pandemic. Moreover, its manufacturing capacity would be vulnerable during pandemics caused by highly pathogenic avian influenza viruses. Therefore, vaccine production using mammalian cell technology is becoming attractive. Current influenza H5N1 vaccine strain (NIBRG-14), a reassortant virus between A/Vietnam/1194/2004 (H5N1) virus and egg-adapted high-growth A/PR/8/1934 virus, could grow efficiently in eggs and MDCK cells but not Vero cells which is the most popular cell line for manufacturing human vaccines. After serial passages and plaque purifications of the NIBRG-14 vaccine virus in Vero cells, one high-growth virus strain (Vero-15) was generated and can grow over 108 TCID50/ml. In conclusion, one high-growth H5N1 vaccine virus was generated in Vero cells, which can be used to manufacture influenza H5N1 vaccines and prepare reassortant vaccine viruses for other influenza A subtypes.

Huang, Mei-Liang; Yeh, Wei-Zhou; Weng, Tsai-Chuan; Chen, Yu-Shuan; Chong, Pele; Lee, Min-Shi

2011-01-01

30

Safety and immunogenicity of inactivated, Vero cell culture-derived whole virus influenza A\\/H5N1 vaccine given alone or with aluminum hydroxide adjuvant in healthy adults  

Microsoft Academic Search

Dosage-sparing strategies, adjuvants and alternative substrates for vaccine production are being explored for influenza vaccine development. We assessed the safety and immunogenicity of a Vero cell culture-grown inactivated whole virus influenza A\\/H5N1 vaccine with or without aluminum hydroxide adjuvant [Al(OH)3] in healthy young adults. Vaccines were well tolerated, but injection site discomfort was more frequent in groups receiving Al(OH)3. Dose-related

Wendy A. Keitel; Cornelia L. Dekker; ChrisAnna Mink; James D. Campbell; Kathryn M. Edwards; Shital M. Patel; Dora Y. Ho; Helen K. Talbot; Kuo Guo; Diana L. Noah; Heather Hill

2009-01-01

31

Promising Rabies Vaccine for Postexposure Prophylaxis in Developing Countries, a Purified Vero Cell Vaccine Produced in China?  

PubMed Central

We evaluated the immunogenicity, safety, and antibody persistence of a Vero cell rabies vaccine manufactured in China, compared with those of Verorab. Adequate titers of antibody were observed for the two vaccines. ChengDa rabies vaccine could be a promising alternative vaccine for many developing countries which cannot afford expensive rabies vaccines.

Wang, Chuanlin; Zhang, Xiaowei; Song, Qingkun; Tang, Kun

2010-01-01

32

Promising rabies vaccine for postexposure prophylaxis in developing countries, a purified vero cell vaccine produced in china.  

PubMed

We evaluated the immunogenicity, safety, and antibody persistence of a Vero cell rabies vaccine manufactured in China, compared with those of Verorab. Adequate titers of antibody were observed for the two vaccines. ChengDa rabies vaccine could be a promising alternative vaccine for many developing countries which cannot afford expensive rabies vaccines. PMID:20147495

Wang, Chuanlin; Zhang, Xiaowei; Song, Qingkun; Tang, Kun

2010-02-10

33

Safety and efficacy of purified vero cell rabies vaccine given intramuscularly and intradermally. (Results of a prospective randomized trial)  

Microsoft Academic Search

Objectives: to determine adverse reactions as a result of pre- and post-exposure rabies vaccination, using the conventional intramuscular, and reduced dose intradermal regimens and purified Vero cell rabies vaccine. Design: a prospective and randomized study of patients exposed to rabies and of subjects in need of pre-exposure rabies vaccination. Setting: a metropolitan rabies control center in a canine rabies endemic

W. Jaiiaroensup; J. Lang; P. Thipkong; O. Wimalaratne; P. Samranwataya; A. Saikasem; S. Chareonwai; W. Yenmuang; S. Prakongsri; V. Sitprija; H. Wilde

1998-01-01

34

The spike protein of severe acute respiratory syndrome (SARS) is cleaved in virus infected Vero-E6 cells  

Microsoft Academic Search

Spike protein is one of the major structural proteins of severe acute respiratory syndrome-coronavirus. It is essential for the interaction of the virons with host cell receptors and subsequent fusion of the viral envelop with host cell membrane to allow infection. Some spike proteins of coronavirus, such as MHV, HCoV-OC43, AIBV and BcoV, are proteolytically cleaved into two subunits, S1

Xiao Dong WU; Bo SHANG; Rui Fu YANG; Hao YU; Zhi Hai MA; Xu SHEN; Yong Yong JI; Ying LIN; Ya Di WU; Guo Mei LIN; Lin TIAN; Xiao Qing GAN; Sheng YANG; Wei Hong JIANG; Er Hei DAI; Xiao Yi WANG; Hua Liang JIANG; You Hua XIE; Xue Liang ZHU; Gang PEI; Lin LI; Jia Rui WU; Bing SUN

2004-01-01

35

Chemical Mutagenesis of Dengue Virus Type 4 Yields Mutant Viruses Which Are Temperature Sensitive in Vero Cells or Human Liver Cells and Attenuated in Mice  

PubMed Central

A recombinant live attenuated dengue virus type 4 (DEN4) vaccine candidate, 2A?30, was found previously to be generally well tolerated in humans, but a rash and an elevation of liver enzymes in the serum occurred in some vaccinees. 2A?30, a non-temperature-sensitive (non-ts) virus, contains a 30-nucleotide deletion (?30) in the 3? untranslated region (UTR) of the viral genome. In the present study, chemical mutagenesis of DEN4 was utilized to generate attenuating mutations which may be useful in further attenuation of the 2A?30 candidate vaccine. Wild-type DEN4 2A virus was grown in Vero cells in the presence of 5-fluorouracil, and a panel of 1,248 clones were isolated. Twenty ts mutant viruses were identified that were ts in both simian Vero and human liver HuH-7 cells (n = 13) or only in HuH-7 cells (n = 7). Each of the 20 ts mutant viruses possessed an attenuation phenotype, as indicated by restricted replication in the brains of 7-day-old mice. The complete nucleotide sequence of the 20 ts mutant viruses identified nucleotide substitutions in structural and nonstructural genes as well as in the 5? and 3? UTRs, with more than one change occurring, in general, per mutant virus. A ts mutation in the NS3 protein (nucleotide position 4995) was introduced into a recombinant DEN4 virus possessing the ?30 deletion, thereby creating rDEN4?30-4995, a recombinant virus which is ts and more attenuated than rDEN4?30 virus in the brains of mice. We are assembling a menu of attenuating mutations that should be useful in generating satisfactorily attenuated recombinant dengue vaccine viruses and in increasing our understanding of the pathogenesis of dengue virus.

Blaney, Joseph E.; Johnson, Daniel H.; Firestone, Cai-Yen; Hanson, Christopher T.; Murphy, Brian R.; Whitehead, Stephen S.

2001-01-01

36

Generation of Recombinant Arenavirus for Vaccine Development in FDA-Approved Vero Cells.  

PubMed

The development and implementation of arenavirus reverse genetics represents a significant breakthrough in the arenavirus field (4). The use of cell-based arenavirus minigenome systems together with the ability to generate recombinant infectious arenaviruses with predetermined mutations in their genomes has facilitated the investigation of the contribution of viral determinants to the different steps of the arenavirus life cycle, as well as virus-host interactions and mechanisms of arenavirus pathogenesis (1, 3, 11) . In addition, the development of trisegmented arenaviruses has permitted the use of the arenavirus genome to express additional foreign genes of interest, thus opening the possibility of arenavirus-based vaccine vector applications (5) . Likewise, the development of single-cycle infectious arenaviruses capable of expressing reporter genes provides a new experimental tool to improve the safety of research involving highly pathogenic human arenaviruses (16) . The generation of recombinant arenaviruses using plasmid-based reverse genetics techniques has so far relied on the use of rodent cell lines (7,19) , which poses some barriers for the development of Food and Drug Administration (FDA)-licensed vaccine or vaccine vectors. To overcome this obstacle, we describe here the efficient generation of recombinant arenaviruses in FDA-approved Vero cells. PMID:23928556

Cheng, Benson Y H; Ortiz-Riaño, Emilio; de la Torre, Juan Carlos; Martínez-Sobrido, Luis

2013-08-01

37

Evaluation of antiviral activities of curcumin derivatives against HSV-1 in Vero cell line.  

PubMed

Antiviral drug resistance is one of the most common problems in medicine, and, therefore, finding new antiviral agents, especially from natural resources, seems to be necessary. This study was designed to assay the antiviral activity of curcumin and its new derivatives like gallium-curcumin and Cu-curcumin on replication of HSV-1 in cell culture. The research was performed as an in vitro study in which the antiviral activity of different concentrations of three substances including curcumin, Gallium-curcumin and Cu-curcumin were tested on HSV-1. The cytotoxicity of the tested compounds was also evaluated on the Vero cell line. The CC50 values for curcumin, gallium-curcumin and Cu-curcumin were 484.2 microg/mL, 255.8 microg/mL and 326.6 microg/mL, respectively, and the respective IC50 values 33.0 microg/mL, 13.9 microg/mL and 23.1 microg/mL. The calculated SI values were 14.6, 18.4 and 14.1, respectively. The results showed that curcumin and its new derivatives have remarkable antiviral effects on HSV-1 in cell culture. PMID:21299124

Zandi, Keivan; Ramedani, Elissa; Mohammadi, Khosro; Tajbakhsh, Saeed; Deilami, Iman; Rastian, Zahra; Fouladvand, Moradali; Yousefi, Forough; Farshadpour, Fatemeh

2010-12-01

38

Assessment of in vitro prophylactic and therapeutic efficacy of chloroquine against Chikungunya virus in vero cells.  

PubMed

The resurgence of Chikungunya virus (CHIKV) in the form of unprecedented and explosive epidemics in India and the Indian Ocean islands after a gap of 32 years is a major public health concern. Currently, there is no specific therapy available to treat CHIKV infection. In the present study, the in vitro prophylactic and therapeutic effects of chloroquine on CHIKV replication in Vero cells were investigated. Inhibitory effects were observed when chloroquine was administered pre-infection, post-infection, and concurrent with infection, suggesting that chloroquine has prophylactic and therapeutic potential. The inhibitory effects were confirmed by performing a plaque reduction neutralization test (PRNT), real-time reverse transcriptase (RT)-PCR analysis of viral RNA levels, and cell viability assays. Chloroquine diminished CHIKV infection in a dose-dependent manner, with an effective concentration range of 5-20 microM. Concurrent addition of drug with virus, or treatment of cells prior to infection drastically reduced virus infectivity and viral genome copy number by >/=99.99%. The maximum inhibitory effect of chloroquine was observed within 1-3 hr post-infection (hpi), and treatment was ineffective once the virus successfully passed through the early stages of infection. The mechanism of inhibition of virus activity by chloroquine involved impaired endosomal-mediated virus entry during early stages of virus replication, most likely through the prevention of endocytosis and/or endosomal acidification, based on a comparative evaluation using ammonium chloride, a known lysosomotropic agent. PMID:20336760

Khan, Mohsin; Santhosh, S R; Tiwari, Mugdha; Lakshmana Rao, P V; Parida, Manmohan

2010-05-01

39

Production in Vero cells of an inactivated rabies vaccine from strain FRV/K for animal and human use.  

PubMed

A new concentrated and purified rabies vaccine was produced in Vero cells. Two rabies virus strains, the fixed rabies virus Pasteur (FRV) and Pittman Moore (PM) were adapted to Vero cells by 20 cycles of alternating passages in the brain of weaning mice. Intracerebral (i.c.) inoculation of weaning mice was followed then by 17 and 20 serial passages in Vero cells of RFV and PM strains, respectively. The adapted strains designated as FRV/K and PM/K gave titres of 10(6) +/- 1.5 log (LD50/ml for i.c. inoculated mice) in several harvests taken from one infected cell culture. Pooled harvests were concentrated 20-fold by ultrafiltration and were tested as animal vaccine after inactivation with beta-propiolactone (BPL). Another vaccine preparation destined for human use, in addition to concentration and inactivation, was also purified by gel filtration. Control tests revealed that the antigenic content of different strain FRV/K harvests was very high in comparison with that of strain PM/K and the reference tissue culture vaccine (RIV, Netherland). In sheep the antibody response induced by the FRV/K strain was very high; serum neutralizing index (NI) higher than 4 was reached 40 days after the second vaccine dose, whereas the vaccine preparation from strain PM/K gave NI of 2.3 and the reference vaccine NI of 3.8, respectively. Safety tests in rabbits and guinea pigs showed neither pyrogenicity nor toxicity. PMID:2892381

el-Karamany, R M

1987-08-01

40

Inhibition of toll-like receptor 2-mediated NF-kappaB activation in Vero cells with herpesvirus of turkeys.  

PubMed

In a previous study, vaccination with a live bivalent vaccine consisting of herpesvirus of turkeys (HVT) and SB-1 was found to be associated with distinct cytokine expression patterns and the modulation of cytokine responses in the spleen. This vaccine could play a role in mediating protection against infection with the RB1B strain of Marek's disease virus. In the present study, vectors for chicken Toll-like receptor 1 (chTLR1) and 2 (chTLR2) expression were constructed and transfected into Vero cells. Nuclear factor kappa light-chain enhancer of activated B cell (NF-kappaB) activation was detected after HVT infection. Compared with normal Vero cells, NF-kappaB activation was significantly inhibited by HVT in Vero cells transfected with chTLR1-1, chTLR1-2, or both. The results demonstrate the significant characteristics of HVT in activating TLR2 signaling. chTLR1 plays a key role in TLR2 subfamily-mediated NF-kappaB inhibition after HVT infection. PMID:23901754

Yang, Qingli; Chen, Hao; Wei, Tianchao; Wei, Ping

2013-06-01

41

Metabolic pathways of N-methanocarbathymidine, a novel antiviral agent, in native and herpes simplex virus type 1 infected Vero cells  

Microsoft Academic Search

N-Methanocarbathymidine ((N)-MCT), a thymidine analog incorporating a pseudosugar with a fixed Northern conformation, exhibits potent antiherpetic activity against herpes simplex virus types 1 (HSV-1) and 2 (HSV-2). This study contrasts the metabolic pathway of (N)-MCT and the well-known antiherpetic agent ganciclovir (GCV) in HSV-1-infected and uninfected Vero cells. Treatment of HSV-1 infected Vero cells immediately after viral infection with (N)-MCT

Livnat Zalah; Mahmoud Huleihel; Esther Manor; Alexander Konson; Harry Ford; Victor E Marquez; David G Johns; Riad Agbaria

2002-01-01

42

Herpes Simplex Virus Glycoprotein gA/B: Evidence that the Infected Vero Cell Products Comap and Arise by Proteolysis  

PubMed Central

We recently reported (Pereira et al., Proc. Natl. Acad. Sci. U.S.A. 78:5202-5206, 1981) that herpes simplex virus 1 and 2 glycoproteins, previously designated gA and gB, could not be differentiated by a bank of independently derived type-specific and type-common monoclonal antibodies. We also reported that from lysates of infected Vero cells, all but one monoclonal antibody precipitated gA/B glycoproteins which had faster electrophoretic mobility than the corresponding infected HEp-2 cell glycoproteins and a set of three small polypeptides which we designated g(A + B) reactive polypeptides 1, 2, and 3. Antibody H368, the single exception, failed to react with the gA/B glycoproteins or related antigens accumulating in infected Vero cells. In this paper, we report the following results. (i) The high-apparent-molecular-weight gA/B glycoproteins accumulating in infected HEp-2 cells were cleaved by a proteolytic enzyme contained in Vero cell lysates to yield more rapidly migrating proteins that were indistinguishable from authentic Vero cell gA/B glycoproteins. Like its authentic counterpart, the cleaved gA/B glycoproteins failed to react with H368 monocolonal antibody. In addition, the lysate cleaved HEp-2 cell gA/B glycoproteins into g(A + B) reactive polypeptides 2 and 3. (ii) The proteolytic activity contained in the uninfected cell lysates was inhibited by N-?-p-tosyl-l-lysine chloromethyl ketone and is therefore trypsin-like. (iii) Pulse-chase experiments indicated that the cleavage of gA/B glycoproteins occurred during or soon after translation but that the accumulation of g(A + B) reactive polypeptide 1 was a consequence of a delayed processing event. (iv) Analysis of herpes simplex virus 1 × herpes simplex virus 2 recombinants indicated that the determinants of type-specific immune reactivity and electrophoretic mobility of gA/B glycoproteins and g(A + B) polypeptides map near the right terminus of herpes simplex virus 1 BamHI-G. Images

Pereira, Lenore; Dondero, Dale; Roizman, Bernard

1982-01-01

43

Herpes simplex virus glycoprotein gA/B: evidence that the infected Vero cell products comap and arise by proteolysis.  

PubMed

We recently reported (Pereira et al., Proc. Natl. Acad. Sci. U.S.A. 78:5202-5206, 1981) that herpes simplex virus 1 and 2 glycoproteins, previously designated gA and gB, could not be differentiated by a bank of independently derived type-specific and type-common monoclonal antibodies. We also reported that from lysates of infected Vero cells, all but one monoclonal antibody precipitated gA/B glycoproteins which had faster electrophoretic mobility than the corresponding infected HEp-2 cell glycoproteins and a set of three small polypeptides which we designated g(A + B) reactive polypeptides 1, 2, and 3. Antibody H368, the single exception, failed to react with the gA/B glycoproteins or related antigens accumulating in infected Vero cells. In this paper, we report the following results. (i) The high-apparent-molecular-weight gA/B glycoproteins accumulating in infected HEp-2 cells were cleaved by a proteolytic enzyme contained in Vero cell lysates to yield more rapidly migrating proteins that were indistinguishable from authentic Vero cell gA/B glycoproteins. Like its authentic counterpart, the cleaved gA/B glycoproteins failed to react with H368 monocolonal antibody. In addition, the lysate cleaved HEp-2 cell gA/B glycoproteins into g(A + B) reactive polypeptides 2 and 3. (ii) The proteolytic activity contained in the uninfected cell lysates was inhibited by N-alpha-p-tosyl-l-lysine chloromethyl ketone and is therefore trypsin-like. (iii) Pulse-chase experiments indicated that the cleavage of gA/B glycoproteins occurred during or soon after translation but that the accumulation of g(A + B) reactive polypeptide 1 was a consequence of a delayed processing event. (iv) Analysis of herpes simplex virus 1 x herpes simplex virus 2 recombinants indicated that the determinants of type-specific immune reactivity and electrophoretic mobility of gA/B glycoproteins and g(A + B) polypeptides map near the right terminus of herpes simplex virus 1 BamHI-G. PMID:6292507

Pereira, L; Dondero, D; Roizman, B

1982-10-01

44

In Vitro Induction of Neospora caninum Bradyzoites in Vero Cells Reveals Differential Antigen Expression, Localization, and Host-Cell Recognition of Tachyzoites and Bradyzoites  

PubMed Central

We report on an optimized method for the in vitro culture of tissue cyst-forming Neospora caninum bradyzoites in Vero cells and the separation of viable parasites from host cells. Treatment of tachyzoite-infected Vero cell cultures with 17 ?M sodium nitroprusside for 8 days severely scaled down parasite proliferation, led to reduced expression of tachyzoite surface antigens, and induced the expression of the bradyzoite marker NcBAG1 and the cyst wall antigen recognized by the monoclonal antibody MAbCC2. Transmission electron microscopy demonstrated that intracellular parasites were located within parasitophorous vacuoles that were surrounded by a cyst wall-like structure, and the dense granule antigens NcGRA1, NcGRA2, and NcGRA7 were incorporated into the cyst wall. Adhesion-invasion assays employing purified tachyzoites and bradyzoites showed that tachyzoites adhered to, and invaded, Vero cells with higher efficiency than bradyzoites. However, removal of terminal sialic acid residues from either the host cell or the parasite surface increased the invasion of Vero cells by bradyzoites, but not tachyzoites.

Vonlaufen, Nathalie; Guetg, Nicole; Naguleswaran, Arunasalam; Muller, Norbert; Bjorkman, Camilla; Schares, Gereon; von Blumroeder, Daniela; Ellis, John; Hemphill, Andrew

2004-01-01

45

Invasion of Vero cells and induction of apoptosis in macrophages by pathogenic Leptospira interrogans are correlated with virulence.  

PubMed Central

Interactions of virulent Leptospira interrogans serovar icterohaemorrhagiae strain Verdun with Vero cells (African green monkey kidney fibroblasts) and a monocyte-macrophage-like cell line (J774A.1) were assayed by a double-fluorescence immunolabelling method. Infectivity profiles were investigated according to (i) the duration of contact between leptospires and eukaryotic cells and (ii) the number of in vitro passages after primary isolation from lethally infected guinea pigs. Comparative experiments were conducted with the corresponding high-passage avirulent variant and the saprophytic leptospire Leptospira biflexa Patoc I. In Vero cells, virulent leptospires were quickly internalized from 20 min postinfection, whereas avirulent and saprophytic strains remained extracellularly located. In addition, the virulent strain demonstrated an ability to actively invade the monocyte-macrophage-like J774A.1 cells during the early stages of contact and to induce programmed cell death, as shown by the detection of oligonucleosomes in a quantitative sandwich enzyme immunoassay. In both cellular systems, subsequent in vitro subcultures demonstrated a progressive decrease of the invasiveness, pointing out the necessity of using primocultures of Leptospira for virulence studies. Invasiveness of virulent leptospires was significantly inhibited with monodansylcadaverine, indicating that internalization was dependent on receptor-mediated endocytosis. Invasion of epithelial cells and induction of apoptosis in macrophages may be related to the pathogenicity of Leptospira, and both could contribute to its ability to survive in the host and to escape from the immune response.

Merien, F; Baranton, G; Perolat, P

1997-01-01

46

Production and evaluation of a chromatographically purified Vero cell rabies vaccine (PVRV) in China using microcarrier technology  

PubMed Central

China is a high population country with millions of animal bite cases every year; thus, it is necessary to explore and develop more effective and productive rabies vaccines for human use. To establish a safe, effective, inexpensive and high-yield rabies vaccine, a non-adjuvant purified Vero cell rabies vaccine produced in the SPEEDA PVRV microcarrier bioreactor was developed by Liaoning Chengda Biology Co. Ltd. in China. This vaccine was produced using Vero cells that were cultured in a microcarrier bioreactor. A microcarrier bioreactor containing 25 g/L of Cytodex-1 was used for perfusion culture. The Vero cell culture density was up to 1.2–1.5 × 107 cells/ml, viruses could be constantly harvested for 18–22 days, and the resulting vaccine immunizing potency was ? 4.5 IU/ml. Vaccine safety and immunogenicity post-immunization were also assessed. A total of 602 volunteers were enrolled and divided into two groups that were vaccinated with either SPEEDA PVRV or VERORAB PVRV on days 0, 3, 7, 14 and 28. All subjects vaccinated with SPEEDA PVRV showed no serious local or systemic adverse effects. The positive conversion rate of serum neutralizing antibodies against the rabies virus reached 100% in both the test and control groups (inoculated with VERORAB PVRV) at 14 days and 45 days after vaccination, and no significant difference was found between the neutralizing antibody geometric mean titers (GMTs) of the two groups. SPEEDA PVRV is appropriate for mass production and shows satisfactory clinical safety and immunogenicity for human post-exposure prophylaxis of rabies.

Yu, Pengcheng; Huang, Ying; Zhang, Yibin; Tang, Qing; Liang, Guodong

2012-01-01

47

Safety and immunogenicity of two freeze-dried Vero cell rabies vaccines for human use in post-exposure prophylaxis.  

PubMed

To provide basis for human rabies vaccination in China, the safety and immunogenicity of two freeze-dried Vero cell rabies vaccines for human use were assessed. A total of 250 volunteers were enrolled and divided into two groups: volunteers in Group A (n=200) were vaccinated five doses of Speeda Vero cell rabies vaccine manufactured by Liaoning Chengda Biotechnology Co. Ltd. on day 0, 3, 7, 14, 28 after exposure. Volunteers in Group B (n=50) were treated with Verorab Vero cell rabies vaccine manufactured by Sanofi Pasteur on the same schedule. The local and systematic adverse reactions were observed. Serum neutralizing antibody levels of 80 individuals in Group A and 50 individuals in Group B were tested with RFFIT on day 7, 14, 45, 180, 360 after the first dose. The seroconversion rates in Groups A and B were 40.3% and 37.0% on day 7 after the first dose, 95.5% and 97.7% on day 14, 100% and 100% on day 45, 100% and 100% on day 180, 89.1% and 89.5% on day 360 respectively, indicating no significant differences between the two groups. And no significant differences were found between the neutralizing antibody geometric mean titers (GMTs) of the two groups on day 7, 14, 45, 180 and 360 after the first dose, with the GMTs of day 14, 45, 180 and 360 all higher than 0.5IU/ml. Antibody levels of the two groups peaked around 2 weeks after the full vaccination program, followed by a 55% decrease up to day 180 and another 76% decrease up to day 360. Both groups experienced occasions of transient fever, rash, edema, and scleroma after vaccination. Neither group had any severe adverse reactions. It was concluded that both vaccines showed satisfactory safety and immunogenicity. Booster vaccination is recommended following another exposure after six months since the full vaccination program. PMID:21296694

Wang, Ling-yun; Sun, Mei-ping; Zhang, Xue-chun; Suo, Luo-dan; Xu, Ruo-hui; Zou, Yan-jie; Zuo, Li-bo; Qi, Hua

2011-02-03

48

Antioxidant and antigenotoxic role of recombinant human erythropoeitin against alkylating agents: cisplatin and mitomycin C in cultured Vero cells.  

PubMed

Cisplatin (CDDP) and mitomycin C (MMC), two alkylating agents used against various solid tumours, are a common source of acute kidney injury. Thus, strategies for minimizing CDDP and MMC toxicity are of a clinical interest. In this study, we aimed to investigate the protective role of recombinant human erythropoietin (rhEPO) against oxidative stress and genotoxicity induced by CDDP and MMC in cultured Vero cells. Three types of treatments were performed: (i) cells were treated with rhEPO 24?h before exposure to CDDP/MMC (pre-treatment), (ii) cells were treated with rhEPO and CDDP/MMC simultaneously (co-treatment), (iii) cells were treated with rhEPO 24?h after exposure to CDDP/MMC (post-treatment). Our results showed that rhEPO decreased the reactive oxygen species levels, the malondialdehyde levels and ameliorated glutathione (reduced and oxidized glutathione) modulation induced by CDDP and MMC in cultured Vero cells. Furthermore, rhEPO administration prevented alkylating agents-induced DNA damage accessed by comet test. Altogether, our results suggested a protective role of rhEPO, against CDDP- and MMC-induced oxidative stress and genotoxicity, especially in pre-treatment condition. PMID:23970409

Rjiba-Touati, Karima; Ayed-Boussema, Imen; Soualeh, Nidhal; Achour, Abdellatif; Bacha, Hassen; Abid, Salwa

2013-08-01

49

High cell density perfusion cultures of anchorage-dependent Vero cells in a depth filter perfusion system.  

PubMed

A depth filter perfusion system (DFPS) with polypropylene fibers had been demonstrated to support high density cultures of anchorage-independent hybridoma cells. The DFPS provides advantages of high surface-to-volume ratio of 450-600 cm(2)/cm(3), low cost set-up, easy operation and scale-up. To test the feasibility of using DFPS for high density cultures of anchorage-dependent cells, Vero cells were cultivated in the DFPS. Gelatin coating on polypropylene fibers in the DFPS was necessary to promote cell attachment and growth. Dissolved oxygen (DO) concentrations could be controlled by sparging air into the reservoir vessel through a filter sparger. When DO concentration was controlled above 40% of air saturation in the DFPS with 40 ?m pore size, the maximum cell concentration as estimated on specific lactate production rate, was 3.81×10(7) cells/ml of the total reactor volume. This viable cell concentration is approximately 18 times higher than that obtained in a T-flask batch culture. Taken together, the results obtained here showed the potential of DFPS for high-density cultures of anchorage-dependent cells. PMID:22358557

Choi, S K; Chang, H N; Lee, G M; Kim, I H; Oh, D J

1995-10-01

50

Evaluation of the serum-free medium MDSS2 for the production of poliovirus on vero cells in bioreactors  

Microsoft Academic Search

The serum-free medium MDSS2 (Merten et al., 1994), was used for cultivating Vero cells as well as for producing poliovirus\\u000a (Sabin type 1) in static and in perfused micro-carrier cultures. At slightly different growth rates of 0.0120\\/h and 0.0106\\/h,\\u000a respectively, static cultures in serum-containing (SCM) and serum-free (SFM) medium produced titers of 106.75 and 106.67 TCID50 per 50 µl; signifying

O.-W. Merten; R. Wu; E. Couvé; R. Crainic

1997-01-01

51

Preclinical evaluation of Vaxfectin(®)-adjuvanted Vero cell-derived seasonal split and pandemic whole virus influenza vaccines.  

PubMed

Increasing the potency and supply of seasonal and pandemic influenza vaccines remains an important unmet medical need which may be effectively accomplished with adjuvanted egg- or cell culture-derived vaccines. Vaxfectin(®), a cationic lipid-based adjuvant with a favorable safety profile in phase 1 plasmid DNA vaccines trials, was tested in combination with seasonal split, trivalent and pandemic whole virus, monovalent influenza vaccines produced in Vero cell cultures. Comparison of hemagglutination inhibition (HI) antibody titers in Vaxfectin(®)-adjuvanted to nonadjuvanted vaccinated mice and guinea pigs revealed 3- to 20-fold increases in antibody titers against each of the trivalent influenza virus vaccine strains and 2- to 8-fold increases in antibody titers against the monovalent H5N1 influenza virus vaccine strain. With the vaccine doses tested, comparable antibody responses were induced with formulations that were freshly prepared or refrigerated at conventional 2-8°C storage conditions for up to 6 mo. Comparison of T-cell frequencies measured by interferon-gamma ELISPOT assay between groups revealed increases of between 2- to 10-fold for each of the adjuvanted trivalent strains and up to 22-fold higher with monovalent H5N1 strain. Both trivalent and monovalent vaccines were easy to formulate with Vaxfectin(®) by simple mixing. These preclinical data support further testing of Vaxfectin(®)-adjuvanted Vero cell culture vaccines toward clinical studies designed to assess safety and immunogenicity of these vaccines in humans. PMID:23857272

Smith, Larry R; Wodal, Walter; Crowe, Brian A; Kerschbaum, Astrid; Bruehl, Peter; Schwendinger, Michael G; Savidis-Dacho, Helga; Sullivan, Sean M; Shlapobersky, Mark; Hartikka, Jukka; Rolland, Alain; Barrett, P Noel; Kistner, Otfried

2013-03-06

52

Adaptation of yellow fever virus 17D to Vero cells is associated with mutations in structural and non-structural protein genes.  

PubMed

Serial passaging of yellow fever virus 17D in Vero cells was employed to derive seed material for a novel inactivated vaccine, XRX-001. Two independent passaging series identified a novel lysine to arginine mutation at amino acid 160 of the envelope protein, a surface-exposed residue in structural domain I. A third passage series resulted in an isoleucine to methionine mutation at residue 113 of the NS4B protein, a central membrane spanning region of the protein which has previously been associated with Vero cell adaptation of other mosquito-borne flaviviruses. These studies confirm that flavivirus adaptation to growth in Vero cells can be mediated by structural or non-structural protein mutations. PMID:23602827

Beasley, David W C; Morin, Merribeth; Lamb, Ashley R; Hayman, Edward; Watts, Douglas M; Lee, Cynthia K; Trent, Dennis W; Monath, Thomas P

2013-04-16

53

[The morphological and karyological characteristics of MDCK and vero (B) cells cultures on plant hydrolyzate-based nutrient media].  

PubMed

MDCK and Vero (B) cell cultures were propagated during 10 passages in the experimental nutrient media containing the soybean powder hydrolyzate prepared using trypsin and bromelain enzymes and the rice powder hydrolysate prepared with trypsin and in the control DMEM and SFM4 MegaVir media. The karyological, morphological, and proliferative characteristics of continuous cultures were examined and compared. The experimental media supplied with 3% fetal bovine serum (FBS) (Gibco, U.S.A.) showed high growth-enhancing properties and failed to affect their morphology. After propagated during 10 passages in the experimental media preserved a stable karyotype. MDCK cell cultures in the nutrient media based on rice and soybean powder hydrolyzates low (2%) in FBS caused no substantial changes in the proliferation indices and morphological and karyological characteristics of cell cultures. PMID:21545033

Mikhailova, G R; Mazurkova, N A; Podchernyaeva, R Ya; Ryabchikova, E I; Troshkova, G P; Shishkina, L N

54

Enhanced Growth of Influenza Vaccine Seed Viruses in Vero Cells Mediated by Broadening the Optimal pH Range for Virus Membrane Fusion  

PubMed Central

Vaccination is one of the most effective preventive measures to combat influenza. Prospectively, cell culture-based influenza vaccines play an important role for robust vaccine production in both normal settings and urgent situations, such as during the 2009 pandemic. African green monkey Vero cells are recommended by the World Health Organization as a safe substrate for influenza vaccine production for human use. However, the growth of influenza vaccine seed viruses is occasionally suboptimal in Vero cells, which places limitations on their usefulness for enhanced vaccine production. Here, we present a strategy for the development of vaccine seed viruses with enhanced growth in Vero cells by changing an amino acid residue in the stem region of the HA2 subunit of the hemagglutinin (HA) molecule. This mutation optimized the pH for HA-mediated membrane fusion in Vero cells and enhanced virus growth 100 to 1,000 times in the cell line, providing a promising strategy for cell culture-based influenza vaccines.

Murakami, Shin; Ito, Mutsumi; Takano, Ryo; Katsura, Hiroaki; Shimojima, Masayuki

2012-01-01

55

Inhibition of dengue NS2B-NS3 protease and viral replication in Vero cells by recombinant retrocyclin-1  

PubMed Central

Background Global resurgence of dengue virus infections in many of the tropical and subtropical countries is a major concern. Therefore, there is an urgent need for the development of successful drugs that are both economical and offer a long-lasting protection. The viral NS2B-NS3 serine protease (NS2B-NS3pro) is a promising target for the development of drug-like inhibitors, which are not available at the moment. In this study, we report retrocyclin-1 (RC-1) production in E. coli as a recombinant peptide to test against dengue NS2B-NS3pro. Methods Dengue NS2B-NS3pro was produced as a recombinant single chain protein in E. coli and purified by Ni+ affinity chromatography. The RC-1 peptide was produced in E. coli and the tri-disulphide bonds were reformed in a diluted alkaline environment. Protease assay was performed using a fluorogenic peptide substrate and measured by fluorescence spectrometry. Real-time PCR was used for quantification of dengue serotype 2 (DENV-2) viral RNA produced in Vero cells. Results The RC-1 peptide inhibited the activity of recombinant NS2B-NS3pro with different values at 50% inhibitory concentration (IC50) which are temperature dependent (28°C, 46.1?±?1.7 ?M; 37°C, 21.4?±?1.6 ?M; 40°C, 14.1?±?1.2 ?M). The presence of RC-1 significantly reduced viral replication in Vero cells infected with DENV-2 at simultaneous treatment after 48 hrs (70%) and 75 hrs (85%). Furthermore, moderate reduction in viral replication was observed at pre-treatment mode after 48 hrs (40%) and 72 hrs (38%) and post-treatment at 48 hrs (30%) and 72 hrs (45%). Conclusion Recombinant RC-1 inhibits DENV-2 replication in Vero cells by interfering with the activity of its serine protease. Thus, we propose that recombinant RC-1 is a potent, cost-effective dengue virus inhibitor. Therefore, it is suitable to consider RC-1 as a new candidate for drug development against dengue infection.

2012-01-01

56

Non-linear relationships between aflatoxin B? levels and the biological response of monkey kidney vero cells.  

PubMed

Aflatoxin-producing fungi contaminate food and feed during pre-harvest, storage and processing periods. Once consumed, aflatoxins (AFs) accumulate in tissues, causing illnesses in animals and humans. Most human exposure to AF seems to be a result of consumption of contaminated plant and animal products. The policy of blending and dilution of grain containing higher levels of aflatoxins with uncontaminated grains for use in animal feed implicitly assumes that the deleterious effects of low levels of the toxins are linearly correlated to concentration. This assumption may not be justified, since it involves extrapolation of these nontoxic levels in feed, which are not of further concern. To develop a better understanding of the significance of low dose effects, in the present study, we developed quantitative methods for the detection of biologically active aflatoxin B? (AFB1) in Vero cells by two independent assays: the green fluorescent protein (GFP) assay, as a measure of protein synthesis by the cells, and the microculture tetrazolium (MTT) assay, as a measure of cell viability. The results demonstrate a non-linear dose-response relationship at the cellular level. AFB1 at low concentrations has an opposite biological effect to higher doses that inhibit protein synthesis. Additional studies showed that heat does not affect the stability of AFB1 in milk and that the Vero cell model can be used to determine the presence of bioactive AFB1 in spiked beef, lamb and turkey meat. The implication of the results for the cumulative effects of low amounts of AFB1 in numerous foods is discussed. PMID:23949006

Rasooly, Reuven; Hernlem, Bradley; He, Xiaohua; Friedman, Mendel

2013-08-14

57

Non-Linear Relationships between Aflatoxin B1 Levels and the Biological Response of Monkey Kidney Vero Cells  

PubMed Central

Aflatoxin-producing fungi contaminate food and feed during pre-harvest, storage and processing periods. Once consumed, aflatoxins (AFs) accumulate in tissues, causing illnesses in animals and humans. Most human exposure to AF seems to be a result of consumption of contaminated plant and animal products. The policy of blending and dilution of grain containing higher levels of aflatoxins with uncontaminated grains for use in animal feed implicitly assumes that the deleterious effects of low levels of the toxins are linearly correlated to concentration. This assumption may not be justified, since it involves extrapolation of these nontoxic levels in feed, which are not of further concern. To develop a better understanding of the significance of low dose effects, in the present study, we developed quantitative methods for the detection of biologically active aflatoxin B1 (AFB1) in Vero cells by two independent assays: the green fluorescent protein (GFP) assay, as a measure of protein synthesis by the cells, and the microculture tetrazolium (MTT) assay, as a measure of cell viability. The results demonstrate a non-linear dose-response relationship at the cellular level. AFB1 at low concentrations has an opposite biological effect to higher doses that inhibit protein synthesis. Additional studies showed that heat does not affect the stability of AFB1 in milk and that the Vero cell model can be used to determine the presence of bioactive AFB1 in spiked beef, lamb and turkey meat. The implication of the results for the cumulative effects of low amounts of AFB1 in numerous foods is discussed.

Rasooly, Reuven; Hernlem, Bradley; He, Xiaohua; Friedman, Mendel

2013-01-01

58

Comparison of Madin-Darby Canine Kidney Cells (MDCK) with a Green Monkey Continuous Cell Line (Vero) and Human Lung Embryonated Cells (MRC5) in the Isolation of Influenza A Virus from Nasopharyngeal Aspirates by Shell Vial Culture  

Microsoft Academic Search

We report a comparative study of the MDCK, Vero, and MRC-5 cell lines in the isolation of the influenza A (IA) virus. We studied 746 samples in which 63 IA viruses were isolated. The MDCK line displayed 100% sensitivity, the Vero line displayed 71.4%, and the MRC-5 displayed 57.1%. The MDCK line showed a statistically significant difference with respect to

JORDI REINA; VICTORIA FERNANDEZ-BACA; ISABEL BLANCO; MARIA MUNAR

1997-01-01

59

Differentiation of a Vero cell adapted porcine epidemic diarrhea virus from Korean field strains by restriction fragment length polymorphism analysis of ORF 3  

Microsoft Academic Search

A porcine epidemic diarrhea virus (PEDV) designated DR13 was isolated in Vero cells and serially passaged by level 100. The virus was titrated at regular intervals of the passage level. Open reading frame (ORF) 3 sequences of the virus at passage levels 20, 40, 60, 80, and 100 were aligned and compared using a computer software program. Suitability of the

D. S Song; J. S Yang; J. S Oh; J. H Han; B. K Park

2003-01-01

60

Samarangenin B from Limonium sinense suppresses herpes simplex virus type 1 replication in Vero cells by regulation of viral macromolecular synthesis.  

PubMed

Inhibitory effects of ethanolic extracts from 10 Chinese herbs on herpes simplex virus type 1 (HSV-1) replication were investigated. By a bioassay-guided fractionation procedure, samarangenin B (Sam B) was isolated from Limonium sinense; Sam B significantly suppressed HSV-1 multiplication in Vero cells without apparent cytotoxicity. Time-of-addition experiments suggested that the inhibitory action of Sam B on HSV-1 replication was not due to the blocking of virus adsorption. In an attempt to further localize the point in the HSV-1 replication cycle where arrest occurred, a set of key regulatory events leading to viral multiplication was examined, including viral immediate-early (alpha), early (beta), and late (gamma) gene expression and DNA replication. Results indicated that levels of glycoprotein B (gB), gC, gD, gG, and infected-cell protein 5 (ICP5) expression and gB mRNA expression in Vero cells were impeded by Sam B. Data from PCR showed that replication of HSV-1 DNA in Vero cells was arrested by Sam B. Furthermore, Sam B decreased DNA polymerase, ICP0, and ICP4 gene expression in Vero cells. Results of an electrophoretic mobility shift assay demonstrated that Sam B interrupted the formation of an alpha-trans-induction factor/C1/Oct-1/GARAT multiprotein complex. The mechanisms of antiviral action of Sam B seem to be mediated, at least in part, by inhibiting HSV-1 alpha gene expression, including expression of the ICP0 and ICP4 genes, by blocking beta transcripts such as DNA polymerase mRNA, and by arresting HSV-1 DNA synthesis and structural protein expression in Vero cells. These results show that Sam B is an antiviral agent against HSV-1 replication. PMID:12183238

Kuo, Yuh-Chi; Lin, Lie-Chwen; Tsai, Wei-Jern; Chou, Cheng-Jen; Kung, Szu-Hao; Ho, Yen-Hui

2002-09-01

61

Letter to Sponsors Using Vero Cells as a Cell Substrate for ...  

Center for Biologics Evaluation and Research (CBER)

... The term "EOPC" is meant to include cells at ... preferably be described in terms of population ... of Vaccines Research and Review Center for Biologics ... More results from www.fda.gov/biologicsbloodvaccines/safetyavailability

62

Immunogenicity and safety in adults of a new chromatographically purified Vero-cell rabies vaccine (CPRV): a randomized, double-blind trial with purified Vero-cell rabies vaccine (PVRV).  

PubMed

Recent improvements in chromatographic purification procedures have made it possible to develop a new chromatographically purified rabies vaccine (CPRV) by further purifying the current rabies vaccine prepared from Vero-cell culture (Verorab; Pasteur Mérieux Connaught). The immunogenicity and safety of primary immunization, followed by a booster at one year, with CPRV was compared to that of the purified Vero cell vaccine (PVRV) in a randomized, double-blind study carried out at four veterinary schools in France. A total of 330 healthy, male and female, first-year veterinary students, aged at least 18 years and who required pre-exposure rabies prophylaxis, were enrolled in this study. Included subjects were randomly assigned either CPRV (n = 163) or PVRV (n = 167) to be given as a primary immunization series of three intramuscular injections (D0, D7, D28), followed by a booster after 1 year (D365). Blood samples for serological analysis were taken at D0 (before first injection), D28, D42, D180, D365 (before booster) and D379. All subjects developed a strong immune response to the primary series, and at D42, all subjects had seroconverted for rabies neutralizing antibody (serum titre > or = 0.5 IU/ml). The rabies virus-neutralizing antibody GMT value at D42 in the CPRV group (23.0 IU/ml) was non-inferior to that in the PVRV group (29.6 IU/ml), according to a one-sided non-inferiority test. While antibody titres tended to decrease over the period of follow-up, at D365 (before booster), 97.5% subjects in the CPRV group and 98.8% of subjects in the PVRV group remained seroconverted. After booster, although the rabies antibody GMT value in the CPRV group was lower than that in the PVRV group, all subjects in both groups were seroconverted, and the difference is probably not clinically important. The incidence of local and systemic reactions tended to decrease with each dose during the primary immunization series, followed by a slight increase after booster (significant time-effect in an exploratory logistic regression analysis). Although mild or moderate local reactions tended to be more frequent after injection with CPRV compared to PVRV, systemic reactions were reported less often (significant group-effects in exploratory logistic regression analyses). One serious adverse event possibly related to vaccine occurred during this study (severe asthenia after the third dose of PVRV). This comparative study in healthy young adults demonstrates that the new chromatographically purified rabies vaccine is as immunogenic as PVRV, and seems to be associated with fewer systemic reactions. PMID:10403033

Lang, J; Cetre, J C; Picot, N; Lanta, M; Briantais, P; Vital, S; Le Mener, V; Lutsch, C; Rotivel, Y

1998-12-01

63

Vero cells co-infected with Chlamydia trachomatis and herpes simplex virus type 2: a scanning and transmission electron microscope study.  

PubMed

Vero (African Green Monkey Kidney) cells infected with Chlamydia trachomatis (serovar L2) (CT-L2) for 48 hr and superinfected with herpes simplex virus type 2 (HSV-2) were fixed 24 hr later and examined with the transmission electron microscope (TEM) and scanning electron microscope (SEM). Ultrastructural examination of the co-infected cells showed that, although many CT-L2 inclusions were present, most were empty of reticulate bodies or elementary bodies. However, large numbers of viruses were observed in the co-infected Vero cells and, in some instances, were seen inside the CT-L2 inclusions. SEM studies of the co-infected cells revealed a swelling and rounding up of the Vero cells typical of a CT-L2 or HSV-2 infection. The outer surface of the co-infected cells were covered with many long microvilli typical of HSV-2 infection with only a few surface protruberances similar to those found in CT-L2 infected cells. PMID:2545004

Pontefract, R D; Ng, C W; Bergeron, G

64

JNK and PI3k\\/Akt signaling pathways are required for establishing persistent SARS-CoV infection in Vero E6 cells  

Microsoft Academic Search

Persistence was established after most of the SARS-CoV-infected Vero E6 cells died. RNA of the defective interfering virus was not observed in the persistently infected cells by Northern blot analysis. SARS-CoV diluted to 2 PFU failed to establish persistence, suggesting that some particular viruses in the seed virus did not induce persistent infection. Interestingly, a viral receptor, angiotensin converting enzyme

Tetsuya Mizutani; Shuetsu Fukushi; Masayuki Saijo; Ichiro Kurane; Shigeru Morikawa

2005-01-01

65

Morphological Analysis of the Transfer of VSV ts-045 G Glycoprotein from the Endoplasmic Reticulum to the Intermediate Compartment in Vero Cells  

Microsoft Academic Search

Vero cells were infected with the ts-045 strain of vesicular stomatitis virus, and the cells were incubated at 39°C to accumulate the mutant G glycoprotein in the ER as a misfolded aggregate. Cycloheximide was added to the culture medium 3.5 h after infection to prevent further protein synthesis, and the temperature was lowered to 10, 15, or 31°C. At these

Lavinia Vittoria Lotti; Maria Rosaria Torrisi; Maria Carmen Erra; Stefano Bonatti

1996-01-01

66

Autophagic cell death is induced by acetone and ethyl acetate extracts from Eupatorium odoratum in vitro: effects on MCF-7 and vero cell lines.  

PubMed

Eupatorium odoratum (EO) contains many biologically active compounds, the anticancer effects of which are not well documented. This study evaluates the cytotoxic effects and mechanism of action of EO extracts on MCF-7 and Vero cell lines. Evaluation of the cytotoxic activity using MTT assay, morphological alterations, and apoptosis were carried out. Autophagy was evaluated by LC3-A protein expression. Cytotoxic activity, membrane blebbing and ballooning at 24 hours, replacement by mass vacuolation, and double membrane vesicles mimicking autophagy and cell death were observed in the cancer cells. No apoptosis was observed by DNA fragmentation assay. Overexpression of LC3-A protein indicated autophagic cell death. Cell cycle analysis showed G0 and G2/M arrest. The Vero cells did not show significant cell death at concentrations <100??g/mL. These results thus suggest that acetone and ethyl acetate extracts of EO induce cell death through induction of autophagy and hold potential for development as potential anticancer drugs. PMID:22666123

Harun, Faizah Bt; Syed Sahil Jamalullail, Syed Mohsin; Yin, Khoo Boon; Othman, Zulkhairi; Tilwari, Anita; Balaram, Prabha

2012-04-30

67

Apoptosis induction in BEFV-infected Vero and MDBK cells through Src-dependent JNK activation regulates caspase-3 and mitochondria pathways  

PubMed Central

Our previous report demonstrated that bovine ephemeral fever virus (BEFV)-infected cultured cells could induce caspase-dependent apoptosis. This study aims to further elucidate how BEFV activates the caspase cascade in bovine cells. BEFV replicated and induced apoptosis in Vero and Madin-Darby bovine kidney (MDBK) cells, and a kinetic study showed a higher efficiency of replication and a greater apoptosis induction ability of BEFV in Vero cells. Src and c-Jun N-terminal kinase (JNK) inhibitor, but not extracellular signal-regulated kinase (ERK) or p38 inhibitor, alleviated BEFV-mediated cytopathic effect and apoptosis. In BEFV-infected Vero and MDBK cells, BEFV directly induced Src tyrosine-418 phosphorylation and JNK phosphorylation and kinase activity, which was inhibited specifically by SU6656 and SP600125, respectively. The caspase cascade and its downstream effectors, Poly (ADP-ribose) polymerase (PARP) and DFF45, were also activated simultaneously upon BEFV infection. In addition, cytochrome c, but not Smac/DIABLO, was released gradually from mitochondria after BEFV infection. SU6656 suppressed Src, JNK, and caspase-3 and -9 activation, as well as PARP and DFF45 cleavage; SP600125 reduced JNK and caspase-3 and -9 activation, as well as PARP and DFF45 cleavage. Taken together, these results strongly support the hypothesis that a Src-dependent JNK signaling pathway plays a key role in BEFV-induced apoptosis. The molecular mechanism identified in our study may provide useful information for the treatment of BEFV.

Chen, Chun-Yen; Chang, Chin-Yang; Liu, Hung-Jen; Liao, Ming-Huei; Chang, Chi-I; Hsu, Jue-Liang; Shih, Wen-Ling

2009-01-01

68

Microarray and real-time RT-PCR analyses of differential human gene expression patterns induced by severe acute respiratory syndrome (SARS) coronavirus infection of Vero cells  

Microsoft Academic Search

Vero E6 African green monkey kidney cells are highly susceptible to infection with the newly emerging severe acute respiratory syndrome coronavirus (SARS-CoV), and they are permissive for rapid viral replication, with resultant cytopathic effects. We employed cDNA microarray analysis to characterize the cellular transcriptional responses of homologous human genes at 12 h post-infection. Seventy mRNA transcripts belonging to various functional classes

W. F. Leong; H. C. Tan; E. E. Ooi; D. R. Koh; Vincent T. K. Chow

2005-01-01

69

In vitro susceptibilities of Bartonella and Rickettsia spp. to fluoroquinolone antibiotics as determined by immunofluorescent antibody analysis of infected Vero cell monolayers  

Microsoft Academic Search

The in vitro susceptibilities of Bartonella and Rickettsia spp. to different concentrations of ciprofloxacin, levofloxacin, ofloxacin and sparfloxacin in Vero cell cultures, were determined by enumeration of immunofluorescent-stained bacilli. After incubation in a CO2-enriched atmosphere, inocula were replaced and tested with media containing 12 different concentrations of each antibiotic in replicate for each species and the monolayers were re-incubated. Growth

Timothy J Ives; Eric L Marston; Russell L Regnery; John D Butts

2001-01-01

70

A vero cell-derived whole-virus H5N1 vaccine effectively induces neuraminidase-inhibiting antibodies.  

PubMed

A Vero cell-derived whole-virus H5N1 influenza vaccine has been shown to induce neutralizing antibodies directed against the hemagglutinin (HA) protein of diverse H5N1 strains in animal studies and clinical trials. However, neuraminidase-inhibiting (NAi) antibodies can reduce viral spread and may be of particular importance in the event of an H5N1 pandemic, where immunity due to HA antibodies is likely absent in the general population. Here we demonstrate the effective induction of NAi antibody titers after H5N1 vaccination in humans. In contrast to the immune response directed toward HA, a single vaccine dose induced a strong NAi response that was not significantly boosted by a second dose, most probably due to priming by previous vaccination or infection with seasonal influenza viruses. After 2 immunizations, seroconversion rates based on antibody titers against HA and NA were similar, indicating the induction of equally strong immune responses against both proteins by this H5N1 vaccine. PMID:22090447

Fritz, Richard; Sabarth, Nicolas; Kiermayr, Stefan; Hohenadl, Christine; Howard, M Keith; Ilk, Reinhard; Kistner, Otfried; Ehrlich, Hartmut J; Barrett, P Noel; Kreil, Thomas R

2011-11-16

71

Bicarbonate/chloride antiport in Vero cells: II. Mechanisms for bicarbonate-dependent regulation of intracellular pH  

SciTech Connect

The rates of bicarbonate-dependent uptake and efflux of /sup 22/Na/sup +/ in Vero cells were studied and compared with the uptake and efflux of /sup 36/Cl/sup -/. Both processes were strongly inhibited by DIDS. Whereas the transport of chloride increased approximately ten-fold when the internal pH was increased over a narrow range around neutrality, the uptake of Na/sup +/ was much less affected by changes in pH. The bicarbonate-linked uptake of /sup 22/Na/sup +/ was dependent on internal Cl- but not on internal Na/sup +/. At a constant external concentration of HCO/sub 3/-, the amount of /sup 22/Na/sup +/ associated with the cells increased when the internal concentration of HCO/sub 3/- decreased and vice versa, which is compatible with the possibility that the ion pair NaCO/sub 3/- is the transported species and that the transport is symmetric across the membrane. Bicarbonate inhibited the uptake of /sup 36/Cl/sup -/ both in the absence and presence of Na/sup +/. At alkaline internal pH, HCO/sub 3/- stimulated the efflux of /sup 36/Cl/sup -/ from preloaded cells, while at acidic internal pH both Na/sup +/ and HCO/sub 3/- were required to induce /sup 36/Cl/sup -/ efflux. We propose a model for how bicarbonate-dependent regulation of the internal pH may occur. This model implies the existence of two bicarbonate transport mechanisms that, under physiological conditions, transport OH(-)-equivalents in opposite directions across the plasma membrane.

Olsnes, S.; Ludt, J.; Tonnessen, T.I.; Sandvig, K.

1987-08-01

72

Immunogenicity and safety of purified Vero-cell rabies vaccine in severely rabies-exposed patients in China.  

PubMed

The immunogenicity and safety of a purified Vero-cell rabies vaccine (PVRV, VERORAB; Aventis Pasteur, France) were evaluated in 171 patients treated for severe exposure to rabies (WHO category III contacts) at the Shandong Provincial Antiepidemic Station in Jinan and an EPI center in Ping Yin, China. Post-exposure treatment consisted of a single dose of equine rabies immunoglobulin (ERIG, 40 IU/kg body weight) on Day (D) 0, and intra-muscular administration of PVRV on D 0, 3, 7, 14 and 28. Antirabies antibody levels were evaluated on D 0, 7, 14, 28, 90 and 180 using the rapid fluorescent focus inhibition test. By D 14 all subjects had seroconverted (> or = 0.5 IU/ml), with a geometric mean titer of 50.3 IU/ml. Antibody titers remained above the seroprotection threshold in all patients for 3 months, and in 98.2% of subjects for 6 months. All patients were still alive 6 months after the start of treatment. PVRV and ERIG were shown to be well tolerated and no serious adverse events were observed. Following PVRV administration, 12 patients (7.0%) had at least one local reaction (mostly pruritus, erythematous rash and pain). Fourteen patients (8.2%) developed local reactions at the site of ERIG administration. Twelve patients (7.0%) developed systemic reactions following post-exposure treatment, the most frequent of which were pruritus, rash and vertigo. This study demonstrates that PVRV is immunogenic and safe in Chinese patients treated according to WHO recommendations for severe rabies exposure. PMID:11127328

Wang, X J; Lang, J; Tao, X R; Shu, J D; Le Mener, V; Wood, S C; Huang, J T; Zhao, S L

2000-06-01

73

Degradation of cellular mRNAs induced by a virion-associated factor during herpes simplex virus infection of Vero cells.  

PubMed Central

We have used Northern blot hybridization to study the accumulation of specific cellular mRNAs in Vero cells infected with herpes simplex virus (HSV) type 1 or type 2. HSV-1 infection decreased the cytoplasmic levels of beta- and gamma-actin, beta-tubulin, and histone H3 and H4 mRNAs, though not all at the same rate. HSV-2 infection resulted in a more rapid decrease in actin and histone mRNA levels compared with HSV-1 infection. The turnover rate of each type of mRNA studied was accelerated in HSV-infected cells compared with the rate in uninfected cells. Cellular mRNA degradation was induced by HSV infection under conditions of (i) inhibition of de novo protein synthesis, (ii) inhibition of de novo RNA synthesis, (iii) infection with HSV-1(17) tsK, which fails to produce early and late viral gene products at the nonpermissive temperature, and (iv) infection with purified virions in the presence of actinomycin D. We have concluded that, in Vero cells, cellular mRNA degradation is induced by a factor associated with the infecting HSV virion and thus does not require de novo RNA or protein synthesis. Despite the overall inhibition of cellular mRNA accumulation, a novel 2.2-kilobase cytoplasmic actin transcript was produced in HSV-infected cells when viral gene expression was allowed. The level of accumulation of cytoplasmic host mRNAs was compared with the rate of cellular protein synthesis under different conditions of infection. This analysis suggests that both HSV-1 and HSV-2 require an additional function(s) to completely inhibit cellular protein synthesis. Images

Schek, N; Bachenheimer, S L

1985-01-01

74

Preparation and characterization of an anti-inflammatory agent based on a zinc-layered hydroxide-salicylate nanohybrid and its effect on viability of Vero-3 cells.  

PubMed

A new organic-inorganic nanohybrid based on zinc-layered hydroxide intercalated with an anti-inflammatory agent was synthesized through direct reaction of salicylic acid at various concentrations with commercially available zinc oxide. The basal spacing of the pure phase nanohybrid was 15.73 Å, with the salicylate anions arranged in a monolayer form and an angle of 57 degrees between the zinc-layered hydroxide interlayers. Fourier transform infrared study further confirmed intercalation of salicylate into the interlayers of zinc-layered hydroxide. The loading of salicylate in the nanohybrid was estimated to be around 29.66%, and the nanohybrid exhibited the properties of a mesoporous-type material, with greatly enhanced thermal stability of the salicylate compared with its free counterpart. In vitro cytotoxicity assay revealed that free salicylic acid, pure zinc oxide, and the nanohybrid have a mild effect on viability of African green monkey kidney (Vero-3) cells. PMID:23345976

Ramli, Munirah; Hussein, Mohd Zobir; Yusoff, Khatijah

2013-01-16

75

Rapid screening of serum-free media for the growth of adherent Vero cells by using a small-scale and non-invasive tool.  

PubMed

The paper proposes a rapid screening method for a first step improvement of an animal component-free medium dedicated to the growth of the anchorage-dependent Vero cell line. A new, rapid, and non-invasive technique is presented to specifically monitor cultures of adherent cells in 96-well plates. The operating conditions of an image analyzer are adapted to take into account the decrease of cell size when the attached cell density increases. An experimental design is carried out to assess the influence of ten component groups in the original medium. Two groups including protein extracts, growth factor, insulin, glucose, and pyruvate show significant positive effects. The groups with vitamins and molecules related to nitrogenous bases display a less pronounced influence. The mixture of amino acids, B(1) vitamin, magnesium sulfate, and sodium phosphate as well as the couple sodium citrate and ferric chloride lead to a downward trend. The screening results are proved to be scalable in stirred cultures with cells on microcarriers. An improved serum-free medium, with some component groups being removed or added, can be rapidly formulated to reach respectively similar or 1.6 times higher cell density than in the original medium. The results from this global approach could be helpful to further focus experiments on identified medium components. PMID:19504358

Petiot, Emma; Fournier, Frantz; Gény, Cécile; Pinton, Hervé; Marc, Annie

2009-06-09

76

Antibody response of patients after postexposure rabies vaccination with small intradermal doses of purified chick embryo cell vaccine or purified Vero cell rabies vaccine.  

PubMed Central

Although the introduction of tissue culture vaccines for rabies has dramatically improved the immunogenicity and safety of rabies vaccines, they are often prohibitively expensive for developing countries. To examine whether smaller doses of these vaccines could be used, we tested the safety and immunogenicity of purified chick embryo cell vaccine (PCECV) on 211 patients in Thailand with World Health Organization (WHO) category II and III exposures to rabies. The patients presented at two Thai hospitals and were randomized into three groups. Patients in Group 1 received 0.1 ml PCECV intradermally at two sites on days 0, 3, 7, and at one site on days 30 and 90. Group 2 was treated similarly, except that purified Vero cell rabies vaccine (PVRV) was used instead of PCECV. Group 3 received 1.0 ml PCECV intramuscularly on days 0, 3, 7, 14, 30 and 90. After 0, 3, 7, 14, 30 and 90 days serum was collected from the subjects and the geometric mean titres (GMTs) of rabies virus neutralizing antibody determined. After 14 days the GMT of 59 patients vaccinated intradermally with PCECV was equivalent to that of patients who received PVRV. Adverse reactions were more frequent in patients who received vaccines intradermally, indicating the reactions were associated with the route of injection, rather than the vaccine per se. We conclude that PCECV is a safe and highly immunogenic vaccine for postexposure rabies vaccination when administered intradermally in 0.1-ml doses using the two-site method ("2,2,2,0,1,1") recommended by WHO.

Briggs, D. J.; Banzhoff, A.; Nicolay, U.; Sirikwin, S.; Dumavibhat, B.; Tongswas, S.; Wasi, C.

2000-01-01

77

In vitro assessment of the cytotoxicity of nisin, pediocin, and selected colicins on simian virus 40-transfected human colon and Vero monkey kidney cells with trypan blue staining viability assays.  

PubMed

Gram-positive bacterial bacteriocins (nisin and pediocin) and gram-negative bacterial bacteriocins (colicins [Col] E1, E3, E6, E7, and K) were evaluated for cytotoxicity against cultured simian virus 40-transfected human colon (SV40-HC) and Vero monkey kidney (Vero) cells. Bacteriocin-treated cells were assessed for viability by trypan blue staining. Monolayers of SV40-HC and Vero cells were cultured in tissue culture plates (35 degrees C, 10% CO2 in humidified air) with the use of Dulbecco's modified Eagle's medium supplemented with 10% (vol/vol) calf serum. Actively growing cells in the log phase (ca. 10(4) cells per ml) were treated with individual partially purified bacteriocin preparations at 170, 350, and 700 activity units per ml. Duplicate culture plates for each bacteriocin treatment and untreated controls were withdrawn after 16, 32, and 48 h of incubation. Cells were dissociated with trypsin and treated with trypan blue and were then counted in a hemocytometer with the use of a phase-contrast microscope. Viability assays indicated dose-dependent toxicity for some bacteriocins. Nisin, pediocin, and Col E6 were the most cytotoxic bacteriocins; SV40-HC cells demonstrated greater sensitivity than Vero cells did. Some bacteriocins can be toxic to mammalian cells; therefore, bacteriocins intended for use as biopreservatives must be evaluated for toxicity to mammalian cells and for other toxicities. Col E1, Col E3, Col E7, and Col K demonstrated little toxicity at the activities tested, indicating that they are safe and thus have potential for use as food biopreservatives. PMID:12747695

Murinda, S E; Rashid, K A; Roberts, R F

2003-05-01

78

ACAM2000 clonal Vero cell culture vaccinia virus (New York City Board of Health strain)--a second-generation smallpox vaccine for biological defense.  

PubMed

The threat of smallpox as a biological weapon has spurred efforts to create stockpiles of vaccine for emergency preparedness. In lieu of preparing vaccine in animal skin (the original method), we cloned vaccinia virus (New York City Board of Health strain, Dryvax by plaque purification and amplified the clone in cell culture. The overarching goal was to produce a modern vaccine that was equivalent to the currently licensed Dryvax in its preclinical and clinical properties, and could thus reliably protect humans against smallpox. A variety of clones were evaluated, and many were unacceptably virulent in animal models. One clonal virus (ACAM1000) was selected and produced at clinical grade in MRC-5 human diploid cells. ACAM1000 was comparable to Dryvax in immunogenicity and protective activity but was less neurovirulent for mice and nonhuman primates. To meet requirements for large quantities of vaccine after the events of September 11th 2001, the ACAM1000 master virus seed was used to prepare vaccine (designated ACAM2000) at large scale in Vero cells under serum-free conditions. The genomes of ACAM1000 and ACAM2000 had identical nucleotide sequences, and the vaccines had comparable biological phenotypes. ACAM1000 and ACAM2000 were evaluated in three Phase 1 clinical trials. The vaccines produced major cutaneous reactions and evoked neutralizing antibody and cell-mediated immune responses in the vast majority of subjects and had a reactogenicity profile similar to that of Dryvax. PMID:15491873

Monath, Thomas P; Caldwell, Joseph R; Mundt, Wolfgang; Fusco, Joan; Johnson, Casey S; Buller, Mark; Liu, Jian; Gardner, Bridget; Downing, Greg; Blum, Paul S; Kemp, Tracy; Nichols, Richard; Weltzin, Richard

2004-10-01

79

Inhibition of Cytotoxicity of Shiga Toxin of Escherichia coli O157:H7 on Vero Cells by Prosopis alba Griseb (Fabaceae) and Ziziphus mistol Griseb (Rhamnaceae) Extracts.  

PubMed

The capacity of Prosopis alba Griseb. and Ziziphus mistol Griseb. fruit extracts to inhibit the toxic action of Shiga toxin (Stx) was investigated. Purification of Stx from Escherichia coli O157:H7 was performed by saline precipitation and affinity chromatography using a column with globotriaosylceramide, while the fruits were subjected to ethanolic or aqueous extractions. The protective action of both fruits was determined by pre-, co-, and postincubation of one 50% cytotoxic dose per ml of Stx with different concentrations of ethanolic and aqueous extracts in confluent monolayers of Vero cells for 72 h at 37°C (5% CO2). The inhibition of the cytotoxic effect of Stx by fruit extracts was determined by the neutral red vital staining technique. The extraction of the polyphenols and flavonoids was effective, and more polyphenols per milligram of dissolved solids were obtained from P. alba than from Z. mistol. However, there were more flavonoids in Z. mistol than in P. alba. Components of both fruits increased the viability of cells treated with Stx when the extracts were preincubated with Stx for 1 h before being applied to the cell cultures, with the ethanolic extract of P. alba showing 95% cell viability at a concentration of 2.45 mg/ml. The extracts were less effective in protecting cells when Stx, extracts, and cells were coincubated together without a previous incubation of Stx; only the concentrations of 19.46 mg/ml for the P. alba aqueous extract and 3.75 mg/ml for the Z. mistol ethanolic extract resulted in the inhibition of cytotoxicity, with 52 and 56% cell viability occurring, respectively. Investigation into this difference in the protection of cells indicated that the protein molecule of Stx suffered degradation to advanced oxidative protein products during preincubation with extracts, principally with P. alba, which exhibited a greater amount of nonflavonoid polyphenols than Z. mistol. The prooxidant action on Stx favored the cells and enhanced the protective action of both fruits. PMID:24112573

Pellarín, M G; Albrecht, C; Rojas, M J; Aguilar, J J; Konigheim, B S; Paraje, M G; Albesa, I; Eraso, A J

2013-10-01

80

Cytotoxic effects of Eryngium kotschyi and Eryngium maritimum on Hep2, HepG2, Vero and U138 MG cell lines.  

PubMed

Abstract Context: Eryngium maritimum L. and the endemic Eryngium kotschyi Boiss. of the Apiaceae family are used for antiinflammatory, antivenom, antinociceptive and diuretic purposes in folk medicine in Turkey. Objective: This study investigated the cytotoxic effects of the plant extracts belonging to Eryngium L. genus on various cell lines. Materials and methods: Cytotoxic activites of the lyophilized aqueous aereal and root parts of the plant extracts on human hepatocellular carcinoma (HepG2), human laryngeal epidermoid carcinoma (Hep2), human glioma (U138-MG) and African green monkey kidney epithelial (Vero) cell lines at 8.33-266.62?µg/ml concentrations were analyzed by lactate dehydrogenase (LDH) leakage and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) cell viability assays. Results: Inhibitory concentration 50 (IC50) values were found <100?µg/ml in most cases varying around 16.33-125.66?µg/ml. IC50 values for E. kostchyi and E. maritimum root parts on Hep2 cells (32.86 and 30.25?µg/ml, respectively), E. kotschyi aereal, E. maritimum aereal and root parts on HepG2 cells (31.75, 32.42 and 35.01?µg/ml, respectively) by MTT assay were found to be close to the US National Cancer Institute (NCI) recommendations (IC50?cells. The lowest IC50 values according to the LDH method were observed in Hep2 cells and the highest in U138-MG cells. Root parts were found to be more toxic than aereal parts for both plants in both methods in general. Discussion and conclusion: Both plant extracts exerted cytotoxic activity aganist Hep2 and HepG2 cells, with low IC50 values defining their promising anticancer property according to NCI; however, further analysis are needed to confirm their activity. PMID:24028780

Yurdakök, Begüm; Baydan, Emine

2013-09-12

81

Lactobacillus plantarum isolated from kefir protects vero cells from cytotoxicity by type-II shiga toxin from Escherichia coli O157:H7.  

PubMed

Kefir is a fermented-milk beverage originating and widely consumed in the Caucasus as well as in Eastern Europe and is a source of bacteria with potential probiotic properties. Enterohaemorrhagic Escherichia coli producing Shiga toxin is commonly associated with food-transmitted diseases; the most prevalent serotype causing epidemics is Esch. coli O157:H7. The aim of this study was to evaluate the antagonism of Lactobacillus plantarum isolated from kefir against the action on Vero cells of supernatants of the Esch. coli O157:H7 strain 69160 expressing the type-II Shiga toxin (Stx2) and to study the role of the Lactobacillus cell wall in that inhibition. Spent culture supernatants of Esch. coli O157:H7 strain 69160 led to cytotoxic effects on cultured eukaryotic cells as evidenced by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide-cleavage assay or by lactate-dehyrogenase release. Lb. plantarum CIDCA 83114 reduced the cytotoxic activity of Stx present in strain-69160 supernatants, and this protection was markedly higher than those of Lactobacillus kefir CIDCA 83113 and 8348 and Lb. delbrueckii subsp. bulgaricus CIDCA 333. This antagonism of cytotoxicity was mimicked by Lb. plantarum cell walls but was reduced after heating or protease treatments, thus indicating a protein or peptide as being involved in the protection mechanism. The cell surface of the lactobacilli bound the subunit B of Stx thereby decreasing the cytotoxicity. These interactions could constitute the first step in preventing the damage induced by Esch. coli O157:H7 supernatants, thus representing a valuable means of potentially mitigating the noxious effects of this food pathogen. PMID:23186804

Kakisu, Emiliano; Abraham, Analía G; Farinati, Carla Tironi; Ibarra, Cristina; De Antoni, Graciela L

2012-11-27

82

Selection of Escherichia coli heat-labile toxin (LT) inhibitors using both the GM1-ELISA and the cAMP vero cell assay.  

PubMed

Weaned piglets are very susceptible to diarrhea caused by enterotoxigenic Escherichia coli. In the past, various natural components were proposed to have beneficial effects by reducing the effects of diarrheal infectious diseases in humans and animals, and thus may represent an alternative for the use of (prophylactic) antibiotics. Alternatives may inactivate enterotoxigenic Escherichia coli heat-labile toxin (LT) by interfering with toxin binding to the cellular receptor GM1. In this study, various plants and other natural substances were tested for inhibitory properties, in the GM1 binding assay, and in the LT-induced cAMP production in Vero cells. The toxic dose of each compound was determined in a cell viability assay, and the highest nontoxic concentrations were used in the GM1 and cAMP assays. Results demonstrated that only d-(+)-galactose, lactose, N-acetyl-d-galactosamine, and two tea extracts were able to inhibit the binding of LT to its GM1 receptor. In the cAMP assay, only the two tea extracts showed inhibitory activity. This shows that d-(+)-galactose, lactose, and N-acetyl-d-galactosamine can indeed inhibit LT binding to GM1 based on structural homology with GM1 in the absence of living cells. However, in the cAMP assay, d-(+)-galactose, and lactose, N-acetyl-d-galactosamine are apparently metabolized to below their effective inhibitory concentration, likely predicting limited practical applicability in vivo. Both tea extracts maintained their activity in the presence of cells. The active compounds in both are probably polyphenols, which are not easily metabolized, and most likely work by aggregating the toxin. In conclusion, the combination of methods used here is a convenient and fast method for preselecting natural substances containing potentially toxin-binding compounds. Furthermore, if antidiarrhea activity is attributed to compounds found inactive here, their activity is unlikely based on interference with toxin binding. PMID:23692076

Verhelst, Roderick; Schroyen, Martine; Buys, Nadine; Niewold, Theo

2013-05-21

83

A herpes simplex virus 2 glycoprotein D mutant generated by bacterial artificial chromosome mutagenesis is severely impaired for infecting neuronal cells and infects only Vero cells expressing exogenous HVEM.  

PubMed

We constructed a herpes simplex virus 2 (HSV-2) bacterial artificial chromosome (BAC) clone, bHSV2-BAC38, which contains full-length HSV-2 inserted into a BAC vector. Unlike previously reported HSV-2 BAC clones, the virus genome inserted into this BAC clone has no known gene disruptions. Virus derived from the BAC clone had a wild-type phenotype for growth in vitro and for acute infection, latency, and reactivation in mice. HVEM, expressed on epithelial cells and lymphocytes, and nectin-1, expressed on neurons and epithelial cells, are the two principal receptors used by HSV to enter cells. We used the HSV-2 BAC clone to construct an HSV-2 glycoprotein D mutant (HSV2-gD27) with point mutations in amino acids 215, 222, and 223, which are critical for the interaction of gD with nectin-1. HSV2-gD27 infected cells expressing HVEM, including a human epithelial cell line. However, the virus lost the ability to infect cells expressing only nectin-1, including neuronal cell lines, and did not infect ganglia in mice. Surprisingly, we found that HSV2-gD27 could not infect Vero cells unless we transduced the cells with a retrovirus expressing HVEM. High-level expression of HVEM in Vero cells also resulted in increased syncytia and enhanced cell-to-cell spread in cells infected with wild-type HSV-2. The inability of the HSV2-gD27 mutant to infect neuronal cells in vitro or sensory ganglia in mice after intramuscular inoculation suggests that this HSV-2 mutant might be an attractive candidate for a live attenuated HSV-2 vaccine. PMID:22993162

Wang, Kening; Kappel, Justin D; Canders, Caleb; Davila, Wilmer F; Sayre, Dean; Chavez, Mayra; Pesnicak, Lesley; Cohen, Jeffrey I

2012-09-19

84

A Herpes Simplex Virus 2 Glycoprotein D Mutant Generated by Bacterial Artificial Chromosome Mutagenesis Is Severely Impaired for Infecting Neuronal Cells and Infects Only Vero Cells Expressing Exogenous HVEM  

PubMed Central

We constructed a herpes simplex virus 2 (HSV-2) bacterial artificial chromosome (BAC) clone, bHSV2-BAC38, which contains full-length HSV-2 inserted into a BAC vector. Unlike previously reported HSV-2 BAC clones, the virus genome inserted into this BAC clone has no known gene disruptions. Virus derived from the BAC clone had a wild-type phenotype for growth in vitro and for acute infection, latency, and reactivation in mice. HVEM, expressed on epithelial cells and lymphocytes, and nectin-1, expressed on neurons and epithelial cells, are the two principal receptors used by HSV to enter cells. We used the HSV-2 BAC clone to construct an HSV-2 glycoprotein D mutant (HSV2-gD27) with point mutations in amino acids 215, 222, and 223, which are critical for the interaction of gD with nectin-1. HSV2-gD27 infected cells expressing HVEM, including a human epithelial cell line. However, the virus lost the ability to infect cells expressing only nectin-1, including neuronal cell lines, and did not infect ganglia in mice. Surprisingly, we found that HSV2-gD27 could not infect Vero cells unless we transduced the cells with a retrovirus expressing HVEM. High-level expression of HVEM in Vero cells also resulted in increased syncytia and enhanced cell-to-cell spread in cells infected with wild-type HSV-2. The inability of the HSV2-gD27 mutant to infect neuronal cells in vitro or sensory ganglia in mice after intramuscular inoculation suggests that this HSV-2 mutant might be an attractive candidate for a live attenuated HSV-2 vaccine.

Kappel, Justin D.; Canders, Caleb; Davila, Wilmer F.; Sayre, Dean; Chavez, Mayra; Pesnicak, Lesley; Cohen, Jeffrey I.

2012-01-01

85

Adherence of Vero cytotoxin-producing Escherichia cobof serotype 0 157: H7 to human epithelial cells in tissue culture: role of outer membranes as bacterial ad hesins  

Microsoft Academic Search

Summary. Escherichia coli of serotype 01 57 : H7 are Vero cytotoxin-producing enteric pathogens that have recently been associated with outbreaks of haemorrhagic colitis, sporadic cases of haemorrhagic colitis and with the haemolytic uraemic syndrome. The organisms demonstrate attaching and effacing binding to the caecum and colon of orally infected gnotobiotic piglets, chickens and infant rabbits. E. coli 01 57

P. M. SHERMAN

1988-01-01

86

Bovine Milk Inhibits Both Adhesion of Helicobacter pylori to Sulfatide and Helicobacter pylori-Induced Vacuolation of Vero Cells  

Microsoft Academic Search

Adhesion of Helicobacter pylori to gastricmucosal cells is an initial important step incolonization and infection. To study adhesion, weinvestigated whether milk inhibits the adhesion ofHelicobacter pylori to sulfatide, an acidicglycosphingolipid that exists in human gastric mucosaand to which Helicobacter pylori adheres. As a measureof functional significance, we also studied whether milkinhibits Helicobacter pylori-induced vacuolation of Verocells. We used sulfatide-coated polystyrene

Yoshiyuki Hata; Toru Kita; Motonobu Murakami

1999-01-01

87

Complete genome sequence of a Vero cell-adapted isolate of porcine epidemic diarrhea virus in eastern China.  

PubMed

In early 2012, a widespread porcine epidemic diarrhea virus (PEDV) occurred in eastern China. A cell-adapted isolate, SD-M, was at the four-passage level of virulent field strain SD, which was isolated from a 2-day-old dead suckling piglet that had suffered from severe diarrhea in Shandong Province, China. We report here the complete genome sequence of SD-M. This sequence will promote a better understanding of the molecular pathogenesis of PEDV. PMID:23166259

Zhao, Mengjiao; Sun, Zhen; Zhang, Yue; Wang, Guisheng; Wang, Hui; Yang, Fangfang; Tian, Fulin; Jiang, Shijin

2012-12-01

88

Vero response to a cytotoxin of Escherichia coli.  

PubMed Central

A cytotoxin was found in culture filtrates of a number of Escherichia coli strains that differed from the known heat-stable and heat-labile enterotoxins of E. coli. It was cytotoxic for Vero but not for Y-1 or CHO cells, and its effect on Vero was distinctly different from that of heat-labile enterotoxin. It was labile to heat and antigenically different from heat-labile enterotoxin, and membrane filtration indicated a molecular weight of 10,000 to 30,000. Images

Konowalchuk, J; Speirs, J I; Stavric, S

1977-01-01

89

Cell culture (Vero) derived whole virus (H5N1) vaccine based on wild-type virus strain induces cross-protective immune responses  

Microsoft Academic Search

The rapid spread and the transmission to humans of avian influenza virus (H5N1) have induced world-wide fears of a new pandemic and raised concerns over the ability of standard influenza vaccine production methods to rapidly supply sufficient amounts of an effective vaccine. We report here on a robust and flexible strategy which uses wild-type virus grown in a continuous cell

Otfried Kistner; M. Keith Howard; Martin Spruth; Walter Wodal; Peter Brühl; Marijan Gerencer; Brian A. Crowe; Helga Savidis-Dacho; Ian Livey; Manfred Reiter; Ines Mayerhofer; Christa Tauer; Leopold Grillberger; Wolfgang Mundt; Falko G. Falkner; P. Noel Barrett

2007-01-01

90

In Vitro Susceptibilities ofBartonella henselae,B. quintana, B. elizabethae,Rickettsia rickettsii,R. conorii,R. akari, andR. prowazekii to Macrolide Antibiotics as Determined by Immunofluorescent Antibody Analysis of Infected Vero Cell Monolayers  

Microsoft Academic Search

The in vitro susceptibilities ofBartonella(Rochalimaea)henselae,B. quintana,B. elizabethae,Rickettsia akari, R. conorii,R. prowazekii, andR. rickettsiito different concentrations of azithromycin, clarithromycin, dirithro- mycin,erythromycin,androxithromycininVerocellcultureswereevaluated.BartonellaandRickettsiaspp.were allowed to initiate infection of the antibiotic-free Vero cell monolayers, which were maintained in 16-chamber microscope slides in the absence of antibiotics at 32& Ci n aC O 2-enriched atmosphere. The monolayers were then incubated fo r3ht oallow for initial

TIMOTHY J. IVES; PABLO MANZEWITSCH; RUSSELL L. REGNERY; JOHN D. BUTTS; ANDMIZANU KEBEDE

1997-01-01

91

The Products of the Herpes Simplex Virus Type 1 Immediate-Early US1/US1.5 Genes Downregulate Levels of S-Phase-Specific Cyclins and Facilitate Virus Replication in S-Phase Vero Cells  

PubMed Central

Herpes simplex virus type 1 ICP22?/US1.5? mutants initiate viral gene expression in all cells; however, in most cell types, the replication process stalls due to an inability to express ?2 late proteins. Although the function of ICP22/US1.5 has not been established, it has been suggested that these proteins activate, induce, or repress the activity of cellular proteins during infection. In this study, we hypothesized that cell cycle-associated proteins are targets of ICP22/US1.5. For this purpose, we first isolated and characterized an ICP22?/US1.5? mutant virus, 22/n199. Like other ICP22?/US1.5? mutants, 22/n199 replicates in a cell-type-specific manner and fails to induce efficient ?2 late gene expression in restrictive cells. Although synchronization of restrictive human embryonic lung cells in each phase of the cell cycle did not overcome the growth restrictions of 22/n199, synchronization of permissive Vero cells in S phase rendered them less able to support 22/n199 plaque formation and replication. Consistent with this finding, expression of cellular S-phase cyclins was altered in an ICP22/US1.5-dependent manner specifically when S-phase Vero cells were infected. Collectively, these observations support the notion that ICP22/US1.5 deregulates the cell cycle upon infection of S-phase permissive cells by altering expression of key cell cycle regulatory proteins either directly or indirectly.

Orlando, Joseph S.; Astor, Todd L.; Rundle, Scott A.; Schaffer, Priscilla A.

2006-01-01

92

Hydrodynamic effects on BHK cells grown as suspended natural aggregates.  

PubMed

Baby hamster kidney (BHK) cell aggregates grown in stirred vessels with different working volumes and impeller sizes were characterized. Using batch cultures, the range of agitation rates studied (25-100 rpm) led to aggregates with maximum sizes of 150 mum. Necrotic centers were not observed and cell specific productivity was independent of aggregate size. High cell viability was found for both single and adherent cells without an increase in cell death when agitation rate was increased. The increase in agitation rate affected aggregates by reducing their size and increasing their concentration and cell concentration in aggregates, while increasing the fraction of free cells in suspension. The experimental relationship between aggregate size and power dissipation rate per unit of mass was close to -1/4, suggesting a correlation with a critical turbulence microscale; this was independent of vessel scale and impeller geometry over the range investigated. Viscous stresses in the viscous dissipation subrange (below Kolmogoroff eddies) appear to be responsible for aggregate breakage. Under intense agitation BHK cells grown in the absence of microcarriers existed as aggregates without cell damage, whereas cells grown on the surface of microcarriers were largely reduced. This is a clear advantage for scaleup purposes if aggregates are used as a natural immobilization system in stirred vessels. (c) 1995 John Wiley & Sons, Inc. PMID:18623322

Moreira, J L; Alves, P M; Aunins, J G; Carrondo, M J

1995-05-20

93

Diatom Cells Grown and Baked on a Functionalized Mica Surface  

Microsoft Academic Search

We demonstrate the cultivation of diatom cells on a functionalized mica surface and the preparation of frustules on a mica\\u000a surface by baking. Diatom cells were successfully grown on a mica surface treated with 3-aminopropyltriethoxysilane. After\\u000a baking at 400?C for 2 h, frustule structures without the organic components of the diatom cells were successfully observed\\u000a by scanning electron microscopy and atomic

Kazuo Umemura; Yusuke Noguchi; Takuya Ichinose; Yo Hirose; Reiko Kuroda; Shigeki Mayama

2008-01-01

94

Comparison of the antiproliferative activity of crude ethanol extracts of nine salvia species grown in Jordan against breast cancer cell line models  

PubMed Central

Background: The antiproliferative activity of Salvia species grown in Jordan has not been fully evaluated yet. The aim of this work was to study the antiproliferative activity of crude ethanol extracts from nine Salvia species grown in Jordan against a panel of breast cancer cell lines. Material and Methods: Cytotoxic activity was evaluated in human tumor models of breast cancer; MCF-7, T47D, ZR-75-1, and BT 474 by the sulforhodamine B assay. In addition, the extracts were evaluated using a non-transformed cell line (Vero) and normal fibroblast cells in order to demonstrate their selectivity and safety. Results: From the nice ethanol extracts under investigation, those of S. dominica and S. fruticosa showed an inhibitory concentration of 50% of cells (IC50) in concentrations less than 30?g/mL against the four cell lines under investigation. S. syriaca and S. hormium showed an IC50 below 30?g/ml for two out of the four cell lines. S. fruticosa, S. hormium and S. syriaca showed selectivity in their antiproliferative activity against estrogen receptor positive cell lines with minimal toxicity against normal human periodontal fibroblasts. Phytochemical screening using thin layer chromatography indicated the presence of terpenoids, flavonoids and coumarins in all examined extracts. Conclusion: Three of the plant extracts under investigation exhibited antiproliferative activity against breast cancer cells and were shown to be safe and selective. These could be considered as a potential source for novel anticancer therapy.

Abu-Dahab, Rana; Afifi, Fatma; Kasabri, Violet; Majdalawi, Lara; Naffa, Randa

2012-01-01

95

Heteroepitaxially grown InP solar cells  

Microsoft Academic Search

The properties of InP solar cells, processed by OMCVD on silicon substrates with an intermediate GaAs layer (InP\\/GaAs\\/Si) and on GaAs substrates (InP\\/GaAs), were determined before and after irradiation with 10-MeV protons. The preirradiation transport properties were found to be influenced largely by dislocations occurring at the InP-GaAs interface. A carrier removal rate of 1.8×103 cm-1 was observed after irradiation

I. Weinberg; C. K. Swartz; D. J. Brinker; D. M. Wilt

1990-01-01

96

Diatom cells grown and baked on a functionalized mica surface.  

PubMed

We demonstrate the cultivation of diatom cells on a functionalized mica surface and the preparation of frustules on a mica surface by baking. Diatom cells were successfully grown on a mica surface treated with 3-aminopropyltriethoxysilane. After baking at 400 degrees C for 2 h, frustule structures without the organic components of the diatom cells were successfully observed by scanning electron microscopy and atomic force microscopy. Furthermore, the frustules deformed and became slender when a sample was baked at 800 degrees C for 2 h. Our method is effective for the direct characterization of frustule structures and physical properties without changing the configuration of the diatom cells grown on the mica surface. PMID:19669502

Umemura, Kazuo; Noguchi, Yusuke; Ichinose, Takuya; Hirose, Yo; Kuroda, Reiko; Mayama, Shigeki

2008-06-24

97

Genetic Basis of Attenuation of Dengue Virus Type 4 Small Plaque Mutants with Restricted Replication in Suckling Mice and in SCID Mice Transplanted with Human Liver Cells  

Microsoft Academic Search

Mutations that restrict replication of dengue virus have been sought for the generation of recombinant live-attenuated dengue virus vaccines. Dengue virus type 4 (DEN4) was previously grown in Vero cells in the presence of 5-fluorouracil, and the characterization of 1248 mutagenized, Vero cell passaged clones identified 20 temperature-sensitive (ts) mutant viruses that were attenuated (att) in suckling mouse brain (J.

Joseph E. Blaney; Daniel H. Johnson; Gracielle G. Manipon; Cai-Yen Firestone; Christopher T. Hanson; Brian R. Murphy; Stephen S. Whitehead

2002-01-01

98

A comparative study on the safety and immunogenicity of Purified duck embryo vaccine [corrected] (PDEV, Vaxirab) with purified chick embryo cell vaccine (PCEC, Rabipur) and purifed vero cell rabies vaccine (PVRV, Verorab).  

PubMed

Rabies is a fatal but preventable disease. Cell culture vaccines (CCV) and purified duck embryo vaccines (PDEV) are currently recommended by WHO for post-exposure prophylaxis. In India, a PDEV (Vaxirab) is being manufactured and is in use since 2003. In the present study, we have evaluated the safety, immunogenicity and tolerance of this vaccine with two other WHO approved CCVs, viz., purified chick embryo cell vaccine (PCEC, Rabipur) and purified vero cell rabies vaccine (PVRV, Veroroab). This study was an open label, randomized phase IV comparative clinical trial. A total of 152 people bitten by dogs and other animals were recruited from 4 different centres from India. They were randomly assigned to receive one of the vaccines by Essen intramuscular regimen (52 subjects received Vaxirab and 50 each Rabipur and Verorab) and rabies immunoglobulin was also administered in all category III exposures. Their blood samples were collected on day 0 (prior to vaccination), 14, 28, 90 and 180. Side effects if any were monitored. The rabies neutralizing antibody titers in their blood samples were estimated by the rapid fluorescent focus inhibition test (RFFIT). Subjects in all three groups had neutralizing antibody titers by day 14 (>0.5 IU/mL) and geometric mean titers (GMT) observed for different vaccines on all days tested did not vary significantly (p>0.5). Side effects observed were minimal and did not vary significantly among the groups. The results of the present study indicate that PDEV (Vaxirab) is as safe, tolerable and immunogenic as both PCEC (Rabipur) and PVRV (Verorab). Thus this vaccine can be a good alternative to WHO approved CCVs for rabies post-exposure prophylaxis. PMID:19818720

Ashwathnarayana, Doddabele Hanumantaiah; Madhusudana, Shampur Narayana; Sampath, Gadey; Sathpathy, Durga Madhab; Mankeshwar, Ranjit; Ravish, Haradana Halli Shankariah; Ullas, Padinjaremattathil Thankappan; Behra, Tapas Ranjan; Sudarshan, Mysore Kalappa; Gangaboraiah; Shamanna, Manjula

2009-10-08

99

Opposite effects of two different strains of equine herpesvirus 1 infection on cytoskeleton composition in equine dermal ED and African green monkey kidney Vero cell lines: application of scanning cytometry and confocal-microscopy-based image analysis in a quantitative study.  

PubMed

Viruses can reorganize the cytoskeleton and restructure the host cell transport machinery. During infection viruses use different cellular cues and signals to enlist the cytoskeleton for their mission. However, each virus specifically affects the cytoskeleton structure. Thus, the aim of our study was to investigate the cytoskeletal changes in homologous equine dermal (ED) and heterologous Vero cell lines infected with either equine herpesvirus 1 (EHV-1) strain Rac-H or Jan-E. We found that Rac-H strain disrupted actin fibers and reduced F-actin level in ED cells, whereas the virus did not influence Vero cell cytoskeleton. Conversely, the Jan-E strain induced polymerization of both F-actin and MT in Vero cells, but not in ED cells. Confocal-microscopy analysis revealed that alpha-tubulin colocalized with viral antigen in ED cells infected with either Rac-H or Jan-E viruses. Alterations in F-actin and alpha-tubulin were evaluated by confocal microscopy, Microimage analysis and scanning cytometry. This unique combination allowed precise interpretation of confocal-based images showing the cellular events induced by EHV-1. We conclude that examination of viral-induced pathogenic effects in species specific cell lines is more symptomatic than in heterologous cell lines. PMID:20349252

Turowska, A; Pajak, B; Godlewski, M M; Dzieciatkowski, T; Chmielewska, A; Tucholska, A; Banbura, M

2010-03-28

100

SEM of Vesicular Stomatitis Virus Infection in Cell Cultures Grown on Aluminum Foil.  

National Technical Information Service (NTIS)

The scanning electron microscope (SEM) was used to study vesicular stomatitis virus (VSV) infection of cells grown in culture. First attempts to resolve virions on the surface of cells grown on glass were unsuccessful because of electron charging. Aluminu...

J. D. White A. T. McManus

1975-01-01

101

Opposite effects of two different strains of equine herpesvirus 1 infection on cytoskeleton composition in equine dermal ED and African green monkey kidney Vero cell lines: application of scanning cytometry and confocal-microscopy-based image analysis in a quantitative study  

Microsoft Academic Search

Viruses can reorganize the cytoskeleton and restructure the host cell transport machinery. During infection viruses use different\\u000a cellular cues and signals to enlist the cytoskeleton for their mission. However, each virus specifically affects the cytoskeleton\\u000a structure. Thus, the aim of our study was to investigate the cytoskeletal changes in homologous equine dermal (ED) and heterologous\\u000a Vero cell lines infected with

A. Turowska; B. Pajak; M. M. Godlewski; T. Dzieci?tkowski; A. Chmielewska; A. Tucholska; M. Banbura

2010-01-01

102

Pandemic influenza A H1N1 vaccine in recipients of solid organ transplants: immunogenicity and tolerability outcomes after vero cell derived, non-adjuvanted, whole-virion vaccination.  

PubMed

During the 2009/10 pandemic of influenza A (H1N1), the American Society of Transplantation and other health organizations recommended that immunocompromised patients should be vaccinated as the key preventive measure. Since there are no data available for the immunogenicity of the unadjuvanted pandemic influenza vaccine in immunocompromised patients - as opposed to the adjuvanted preparation - the objective of this study was to evaluate the immunogenicity of an adjuvant-free H1N1 vaccine in recipients of solid organ transplants. Patients were recruited at the Vienna General Hospital, Austria. The vaccination schedule consisted of 2 doses of a whole-virion, vero cell derived, inactivated, non-adjuvanted influenza A/California/07/2009 (H1N1) vaccine given with an interval of 3 weeks. A hemagglutination inhibition (HI) assay on blood samples obtained prior to the first and after each vaccination was used for serologic analysis. The primary immunologic endpoint was the seroconversion rate, defined as the proportion of subjects with an individual 4-fold increase in HI titer of at least 1:40. In addition, virus-specific IgG antibodies to the pandemic H1N1 strain were measured using a commercially available ELISA. Twenty-five organ transplant patients (16 males, 9 females) aged 25-79 years were vaccinated and provided blood samples for serologic analysis. The time elapsed since transplantation was 10 months to 25 years (mean: 9 years; 95% CI 6-13 years). The vaccine was well tolerated and no local adverse events were noticed. After two vaccinations 37% of the patients demonstrated seroconversion in the HI assay as defined above and 70% had virus-specific IgG antibodies. Among the HI vaccine responders were 6 of 14 heart transplant recipients and 1 of 4 liver transplant recipients. The number and type of immunosuppressive agents did not significantly differ in their effect on the immune response. Our results show that the novel vero cell derived and adjuvant-free pandemic A/California/07/2009 (H1N1) influenza vaccine induced limited but measurable immune responses in adult recipients of solid organ transplants. PMID:21803100

Lagler, Heimo; Wenisch, Judith M; Tobudic, Selma; Gualdoni, Guido A; Rödler, Susanne; Rasoul-Rockenschaub, Susanne; Jaksch, Peter; Redlberger-Fritz, Monika; Popow-Kraupp, Theresia; Burgmann, Heinz

2011-07-29

103

Polycrystalline MBE-grown GaAs for solar cells  

SciTech Connect

This paper will discuss initial studies of thin-film GaAs grown by molecular-beam epitaxy for use in developing a thin-film GaAs solar cell. Photocurrent and photoluminescence intensity are related to the material morphology as a function of growth conditions. Growth temperature and V/III ratio have a dramatic effect on the photocurrent. However, it seems likely that even after optimizing such growth parameters, it will be necessary to provide substrates that can provide templates to enhance grain size from the start of thin-film growth.

Friedman, D. J.; Kurtz, Sarah R.; Kibbler, A. E.; Al-Jassim, M.; Jones, K.; Keyes, B.; Matson, R. [National Renewable Energy Laboratory, 1617 Cole Blvd., Golden, Colorado 80401 (United States)

1997-02-15

104

Gene therapy with cytokine-transfected xenogenic cells (Vero-IL-2) in patients with metastatic solid tumors: mechanism(s) of elimination of the transgene-carrying cells  

Microsoft Academic Search

Eleven patients with advanced cancer were treated in a clinical gene therapy trial by repeated intra- tumoral injections\\u000a with different doses of xenogenic fibroblasts secreting high amounts of human interleukin-2 (Vero-IL2). Treatments in a total\\u000a of 14 courses were well tolerated and resulted in clinical responses and measurable biological effects. Together with increases\\u000a in serum interleukin-2 (IL-2), modifications of the

Peter Jantscheff; Richard Herrmann; Giulio Spagnoli; Jürgen Reuter; Majid Mehtali; Michael Courtney; Christoph Rochlitz

1999-01-01

105

Photosynthetic Characteristics of Photoautotrophically Grown Tobacco Callus Cells 1  

PubMed Central

Haploid callus cells of tobacco (Nicotiana tabacum) were grown photoautotrophically on a solid agar medium in the absence of sucrose in Petri plates in an atmosphere of 1% or 3% CO2 in air. The averages of dry weight increases for four to five consecutive passages were 2.3- to 3.6-fold per 3-week passage for different subclones. Photosynthetic 14CO2 assimilation was maximum at about 1% CO2 with half-maximal rates obtained at 0.2% CO2. At saturating CO2 concentration the average rate of CO2 fixation was about 5 ?mole per gram fresh weight per hour or about 125 ?mole per mg of chlorophyll per hour. The existence of an active photorespiratory system in these tissues was established in a number of independent ways. The photosynthetic rate in 0.18% CO2 was inhibited 38 to 50% in 100% O2 compared with 21% O2. Glycolate accumulated at a constant rate in the presence of 5 mm ?-hydroxy-2-pyridinemethanesulfonic acid for 20 minutes in light. This rate was rapid relative to the photosynthetic rate. Glycolate synthesis was three times faster in autotrophic than in heterotrophic cells. [1-14C]Glycolate was rapidly metabolized and the products included 14CO2, [14C]glycine, and [14C]serine, thus demonstrating an active glycolate pathway. Photorespiration was demonstrated directly by measurement of an O2-dependent release of 14CO2 in the light from callus that fixed 14CO2 for about 22 hours. Autotrophic growth in 60% O2 and 0.03% CO2 was slowed and ceased entirely after two or three passages, while heterotrophic growth was unaffected by 60% O2 in the atmosphere. The method of growing autotrophic callus which has an active photorespiratory system should facilitate the selection and analysis of photosynthetic mutants in which photorespiration is regulated.

Berlyn, Mary B.; Zelitch, Israel; Beaudette, Pamela D.

1978-01-01

106

Microbial oxidation of cumene by octane-grown cells  

Microsoft Academic Search

Previously, we reported that eight glucose-grown microbial cultures out of 1229 screened oxidize the alkyl side-chain of 2-phenylpropane (cumene) stereospecifically. Now, we have adapted these cultures to grow on n-octane and found that their cumene oxidation activities increased more than 30 times. We also found an additional 11 cultures (ten bacteria, one actinomycete) that oxidized cumene when grown on octane

C. T. Hou; M. A. Jackson; M. O. Bagby; L. A. Becker

1994-01-01

107

Immunogenicity and effectiveness of post-exposure rabies prophylaxis with a new chromatographically purified Vero-cell rabies vaccine (CPRV): a two-stage randomised clinical trial in the Philippines.  

PubMed

Recent improvements in chromatographic purification procedures have made it possible to develop a new chromatographically purified rabies vaccine (CPRV) by further purifying the current rabies vaccine prepared from Vero-cell culture (PVRV) (Verorab; Pasteur Merieux Connaught). The immunogenicity and effectiveness of post-exposure rabies prophylaxis with this new vaccine were evaluated in a two-stage clinical trial conducted in the Philippines. In both study stages. post-exposure treatment consisted of five injections of vaccine [(D)ays 0, 3, 7, 14, 28], together with a dose of rabies immunoglobulin (RIG) of equine or human origin on D0. In stage 1, 231 subjects with low-risk rabies exposure (WHO category I or II), and who had a negative ERIG skin test, were treated with either CPRV (n = 114) or PVRV (n = 117). By D14, all subjects in each group had achieved rabies antibody titres over ten times that recommended by the WHO as indicating seroconversion (> or = 0.5 IU/ml). The kinetics of the immune response to vaccination were very similar in the two groups, and at D28, the immunogenicity of CPRV was equivalent to that of PVRV (one-sided equivalence test). Following these positive results, 132 subjects with severe rabies exposure were included in the second stage of this trial. All were scheduled to receive four vaccine doses with CPRV. After D14, only those 57 patients with confirmed rabies exposure (animal with positive FA test) and seven patients for whom rabies exposure could not be excluded (animal lost or not tested) completed the treatment and were followed for one year to assess survival. After 1 year, 62 patients treated for confirmed or possible severe rabies exposure had been examined and were still alive. Two patients contacted by letter and telephone confirmed good health 7 and 16 months after exposure. No severe local or systemic reactions were reported in either stage of the study, and no treatment-related serious adverse event occurred. This two-stage clinical trial attests to the safety and satisfactory immunogenicity of CPRV in post-exposure rabies treatment, and confirms the effectiveness of a new rabies vaccine in patients with severe confirmed exposure. PMID:10708006

Quiambao, B P; Lang, J; Vital, S; Montalban, C G; Le Mener, V; Wood, S C; Miranda, E

2000-02-25

108

Comparison of cytochromes from anaerobically and aerobically grown cells of Pseudomonas perfectomarinus  

Microsoft Academic Search

Pseudomonas perfectomarinus (ATCC 14405) is a facultative anaerobe capable of either oxygen respiration or anaerobic nitrate respiration, i.e., denitrification. A comparative study of the electron transfer components of cells revealed five c-type cytochromes and cytochrome cd in the soluble fraction from anaerobically grown cells and four c-type cytochromes in the soluble fraction from anaerobically grown cells. Purification procedures yielded three

M. C. Liu; W. J. Payne; H. D. Jr. Peck; J. LeGall

1983-01-01

109

Interaction between Wall Deposition and Cell Elongation in Dark-Grown Hypocotyl Cells in Arabidopsis1  

PubMed Central

A central problem in plant biology is how cell expansion is coordinated with wall synthesis. We have studied growth and wall deposition in epidermal cells of dark-grown Arabidopsis hypocotyls. Cells elongated in a biphasic pattern, slowly first and rapidly thereafter. The growth acceleration was initiated at the hypocotyl base and propagated acropetally. Using transmission and scanning electron microscopy, we analyzed walls in slowly and rapidly growing cells in 4-d-old dark-grown seedlings. We observed thick walls in slowly growing cells and thin walls in rapidly growing cells, which indicates that the rate of cell wall synthesis was not coupled to the cell elongation rate. The thick walls showed a polylamellated architecture, whereas polysaccharides in thin walls were axially oriented. Interestingly, innermost cellulose microfibrils were transversely oriented in both slowly and rapidly growing cells. This suggested that transversely deposited microfibrils reoriented in deeper layers of the expanding wall. No growth acceleration, only slow growth, was observed in the cellulose synthase mutant cesA6prc1-1 or in seedlings, which had been treated with the cellulose synthesis inhibitor isoxaben. In these seedlings, innermost microfibrils were transversely oriented and not randomized as has been reported for other cellulose-deficient mutants or following treatment with dichlorobenzonitrile. Interestingly, isoxaben treatment after the initiation of the growth acceleration in the hypocotyl did not affect subsequent cell elongation. Together, these results show that rapid cell elongation, which involves extensive remodeling of the cell wall polymer network, depends on normal cellulose deposition during the slow growth phase.

Refregier, Guislaine; Pelletier, Sandra; Jaillard, Danielle; Hofte, Herman

2004-01-01

110

Application of Optical Trapping for Cells Grown on Plates: Optimization of PCR and Fidelity of DNA Sequencing of p53 Gene from a Single Cell  

Microsoft Academic Search

Background: Optical trapping has traditionally been used to visually select and isolate nonadherent cells grown in suspension because cells grown in monolayers will rapidly reattach to surfaces if suspended in solu- tion. We explored methods to slow cell reattachment that are also compatible with high-fidelity PCR. Methods: Using HeLa cells grown on plates and sus- pended after trypsinization, we measured

James M. Gale; Christopher P. Romero; Gregory B. Tafoya; Jerome Conia

111

Comparison of cytochromes from anaerobically and aerobically grown cells of Pseudomonas perfectomarinus  

SciTech Connect

Pseudomonas perfectomarinus (ATCC 14405) is a facultative anaerobe capable of either oxygen respiration or anaerobic nitrate respiration, i.e., denitrification. A comparative study of the electron transfer components of cells revealed five c-type cytochromes and cytochrome cd in the soluble fraction from anaerobically grown cells and four c-type cytochromes in the soluble fraction from anaerobically grown cells. Purification procedures yielded three c-type cytochromes (designated c-551, c-554, and acidic c-type) from both kinds of cells as indicated by similarities in absorption spectra, molecular weight, and electrophoretic mobility. Cytochrome cd, a diheme c-type cytochrome (cytochrome c-552), and a spilt-..cap alpha..-c-type cytochrome with a low ratio of ..cap alpha.. to ..beta.. absorption peak heights was uniquely present in the aerobically grown cells. Liquid N/sub 2/ temperature absorption spectroscopy on the membrane fraction from anaerobically grown cells revealed residual cytochrome cd as well as differences in the relative amounts of c-type and b-type cytochromes in membranes prepared from cells grown under the two different conditions. 28 references, 3 figures, 3 tables.

Liu, M.C.; Payne, W.J.; Peck, H.D. Jr.; LeGall, J.

1983-04-01

112

Efficacy and safety of cell associated vaccines against Marek's disease virus grown in a continuous cell line from chickens  

Microsoft Academic Search

The Marek's disease virus (MDV) vaccine strains CVI 988 and herpes virus of turkeys (HVT) strain FC126, usually are grown in primary chicken embryo fibroblasts (CEF). We found that the strains could be grown also in the so-called JBJ-1 cell line to titres in the same range as when chicken embryo fibroblasts were used. The JBJ-1 cell line is a

Harm Geerligs; Sandra Quanz; Brenda Suurland; Ine E. M. Spijkers; Jeff Rodenberg; Frans G. Davelaar; Berend Jongsma; Mahesh Kumar

2008-01-01

113

Electron microscopic investigations of zymomonas mobilis cells grown in low and high glucose concentrations  

Microsoft Academic Search

Zymomonas mobilis cells grown in the presence of low and high glucose concentrations were examined by electron microscopy. Using ultrathin sectioning and agar diffusion method, significant changes in morphology were observed. Although the fine structure resembles that of a typical gram-negative bacterium, changes in glucose concentration and phases of growth lead to large cell wall vesicle or blebs formation. The

Horst W. Doelle; Hansdiirgen Preusser; Heidi Rostek

1982-01-01

114

RADIATION-INDUCED CHROMOSOME ABERRATIONS IN HUMAN FETAL CELLS GROWN IN VITRO  

Microsoft Academic Search

Diploid human cells (from fetal lung and brain) grown in. vitro were ; irradiated with Co⁶° gamma rays. The effect of radiation was measured by ; recording postmetaphase chromosomal aberrations in cell cultures fixed and ; stained 24 and 48 hr after acute irradiation. Spontaneous aberration frequencies ; were determined in matched control cultures. The frequency of spontaneous ; aberrations

Boeok

1962-01-01

115

Single cell protein production by photosynthetic bacteria grown on the clarified effluents of biogas plant  

Microsoft Academic Search

Anaerobically digested cow dung was separated by centrifugation into solid residue and liquid supernatant fractions. Clarified supernatant fraction, rich in volatile fatty acids, supported the growth of photosynthetic bacteria. Single cell protein from different photosynthetic bacteria, grown on clarified supernatant, was found to be rich in essential and sulphur amino acids. Rhodopseudomonas capsulata produced the best single cell protein.

Sudhanshu Vrati; G. B. Pant

1984-01-01

116

Changing cell-wall compositions in hypocotyls of dark-grown bean seedlings  

Microsoft Academic Search

Hypocotyls of dark-grown 6-day-old seedlings of Phaseolus vulgaris L. proved to be sufficiently homogeneous to permit studies relating the rate of cell elongation to the composition of the primary cell walls. Whereas the levels of cellulose and uronic acids remained practically constant during and after cell extension, all other components showed major or minor changes. Cell-wall protein, as such, decreased

G. J. Holst; F. M. Klis; F. Bouman; D. Stegwee

1980-01-01

117

Efficacy and safety of cell associated vaccines against Marek's disease virus grown in a continuous cell line from chickens.  

PubMed

The Marek's disease virus (MDV) vaccine strains CVI 988 and herpes virus of turkeys (HVT) strain FC126, usually are grown in primary chicken embryo fibroblasts (CEF). We found that the strains could be grown also in the so-called JBJ-1 cell line to titres in the same range as when chicken embryo fibroblasts were used. The JBJ-1 cell line is a fibroblast-like continuous chicken cell line, which can be grown in flat bottom tissue culture flasks, roller bottles and on micro carriers. We investigated the efficacy of experimental CVI 988 vaccines grown in JBJ-1 cells and the efficacy of combinations of CVI 988 grown in JBJ-1 cells with HVT FC 126 also grown in JBJ-1 cells. The study was performed in accordance with European Pharmacopoeia monograph 0589 for live MDV disease vaccines. Groups of 1-day-old SPF chicks were vaccinated subcutaneously or intramuscularly, with 10(2.5) TCID50 per dose of CVI 988 alone or in combination with 500PFU per dose of HVT. As a control a group vaccinated with CVI 988 grown in CEF was included. One group was not vaccinated. Five days after vaccination all chickens were challenged with the very virulent MDV strain RB1B. After challenge the chickens were observed for a period of 70 days for signs of Marek's disease (MD). The protection induced by CVI 988 grown in JBJ-1 cells and the combination of CVI 988 and HVT-FC126 both grown in JBJ-1 cells, amply complied with the requirements of the European Pharmacopoeia which prescribes that the protection index should be at least 80%. The safety of the vaccines grown in JBJ-1 cells was tested in a field study in commercial layer chickens. No signs of MD were noticed during the study and no other signs attributable to the vaccine. It is concluded that the JBJ-1 cell line is a suitable substrate for the current vaccines against MD. PMID:18706949

Geerligs, Harm; Quanz, Sandra; Suurland, Brenda; Spijkers, Ine E M; Rodenberg, Jeff; Davelaar, Frans G; Jongsma, Berend; Kumar, Mahesh

2008-08-14

118

Iron content of Saccharomyces cerevisiae cells grown under iron-deficient and iron-overload conditions.  

PubMed

Fermenting cells were grown under Fe-deficient and Fe-overload conditions, and their Fe contents were examined using biophysical spectroscopies. The high-affinity Fe import pathway was active only in Fe-deficient cells. Such cells contained ~150 ?M Fe, distributed primarily into nonheme high-spin (NHHS) Fe(II) species and mitochondrial Fe. Most NHHS Fe(II) was not located in mitochondria, and its function is unknown. Mitochondria isolated from Fe-deficient cells contained [Fe(4)S(4)](2+) clusters, low- and high-spin hemes, S = (1)/(2) [Fe(2)S(2)](+) clusters, NHHS Fe(II) species, and [Fe(2)S(2)](2+) clusters. The presence of [Fe(2)S(2)](2+) clusters was unprecedented; their presence in previous samples was obscured by the spectroscopic signature of Fe(III) nanoparticles, which are absent in Fe-deficient cells. Whether Fe-deficient cells were grown under fermenting or respirofermenting conditions had no effect on Fe content; such cells prioritized their use of Fe to essential forms devoid of nanoparticles and vacuolar Fe. The majority of Mn ions in wild-type yeast cells was electron paramagnetic resonance-active Mn(II) and not located in mitochondria or vacuoles. Fermenting cells grown on Fe-sufficient and Fe-overloaded medium contained 400-450 ?M Fe. In these cells, the concentration of nonmitochondrial NHHS Fe(II) declined 3-fold, relative to that in Fe-deficient cells, whereas the concentration of vacuolar NHHS Fe(III) increased to a limiting cellular concentration of ~300 ?M. Isolated mitochondria contained more NHHS Fe(II) ions and substantial amounts of Fe(III) nanoparticles. The Fe contents of cells grown with excessive Fe in the medium were similar over a 250-fold change in nutrient Fe levels. The ability to limit Fe import prevents cells from becoming overloaded with Fe. PMID:23253189

Holmes-Hampton, Gregory P; Jhurry, Nema D; McCormick, Sean P; Lindahl, Paul A

2012-12-19

119

Endocytic activity of Sertoli cells grown in bicameral culture chambers  

SciTech Connect

Immature rat Sertoli cells were cultured for 7 to 14 days on Millipore filters impregnated with a reconstituted basement membrane extract in dual-environment (bicameral) culture chambers. Electron microscopy of the cultured cells revealed the presence of rod-shaped mitochondria, Golgi apparatus, rough endoplasmic reticulum, and Sertoli-Sertoli tight junctions, typical of these cells in vivo. The endocytic activity of both the apical and basal surfaces of the Sertoli cells was examined by either adding alpha 2-macroglobulin (alpha 2-M) conjugated to 20 nm gold particles to the apical chamber or by adding /sup 125/I labeled alpha 2-M to the basal chamber. During endocytosis from the apical surface of Sertoli cells, the alpha 2-M-gold particles were bound initially to coated pits and then internalized into coated vesicles within 5 minutes. After 10 minutes, the alpha 2-M-gold was found in multi-vesicular bodies (MVBs) and by 30 minutes it was present in the lysosomes. The proportion of alpha 2-M-gold found within endocytic cell organelles after 1 hour of uptake was used to estimate the approximate time that this ligand spent in each type of organelle. The alpha 2-M-gold was present in coated pits, coated vesicles, multivesicular bodies, and lysosomes for approximately 3, 11, 22, and 24 minutes, respectively. This indicates that the initial stages of endocytosis are rapid, whereas MVBs and lysosomes are relatively long-lived.

Dai, R.X.; Djakiew, D.; Dym, M.

1987-07-01

120

Response of cells persistently infected with arenaviruses to superinfection with homotypic and heterotypic viruses.  

PubMed

Vero cell cultures persistently infected with the arenaviruses Junin, Pichinde, Tacaribe, and Tamiami were established and designated Vero-Jun, Vero-Pic, Vero-Tac, and Vero-Tam, respectively. Two types of carrier cultures could be easily distinguished: Vero-Jun and Vero-Tac systems were characterized by a lack of infectious virus production after a few cell transfers, whereas a more productive state with continuous release of virus was observed in Vero-Pic and Vero-Tam cultures. These differences appeared to be related to resistance of the culture to viral superinfection. In fact, Vero-Jun and Vero-Tac cultures totally excluded only the replication of the serologically more closely related arenaviruses Amapari, Junin, or Tacaribe, while the refractoriness of Vero-Pic and Vero-Tam cultures was extended to most of the virus group members. The resistance of Vero-Jun cells to superinfection by Junin or Tacaribe virus could be ascribed to the production of specific uv-resistant Junin interfering particles, which showed a specific range of interference against Junin and Tacaribe viruses. Interfering particles against homotypic and heterotypic arenaviruses were isolated from Vero-Pic cultures. However, the degree of interference developed by these Pic-interfering particles was not enough to fully explain reinfecting virus exclusion from Vero-Pic cultures. Viral susceptibility of persistent cultures is proposed as a useful tool to examine relationships of members of the arenavirus group. PMID:6312683

Damonte, E B; Mersich, S E; Coto, C E

1983-09-01

121

Lipid composition of Geotrichum candidum single cell protein grown in continuous submerged culture  

Microsoft Academic Search

Continuous cultivation of Geotricum candidum grown on orange peel extracts produced a high-protein, low-lipid content single cell protein which could be utilized as feed or proteic extract source. The lipid content, ca 4%, was very low compared with the data available in the literature, a result which might be attributed to the fermentation conditions employed in this study. The lipid

M. Ziino; R. B. Lo Curto; F. Salvo; D. Signorino; B. Chiofalo; D. Giuffrida

1999-01-01

122

Electrophysiological properties of tissue cultured heart cells grown in a linear array  

Microsoft Academic Search

Summary Embryonic chick heart cells were grown in tissue culture on an oriented substrate (channels cut in an agar coated slide), so that they formed narrow (5–100 µ) strands of arbitrary length. The electrical properties of these strands were examined using intracellular microelectrodes ac and dc cable studies were performed to determine the passive cable parameters. Quantitative histology, using light

Frederick Sachs

1976-01-01

123

Plastid distribution in columella cells of a starchless Arabidopsis mutant grown in microgravity.  

PubMed

Wild-type and starchless Arabidopsis thaliana mutant seedlings (TC7) were grown and fixed in the microgravity environment of a U.S. Space Shuttle spaceflight. Computer image analysis of longitudinal sections from columella cells suggest a different plastid positioning mechanism for mutant and wild-type in the absence of gravity. PMID:9177036

Hilaire, E; Paulsen, A Q; Brown, C S; Guikema, J A

1997-04-01

124

Comparison of electrogenic capabilities of microbial fuel cell with different light power on algae grown cathode.  

PubMed

Electricity generation capabilities of microbial fuel cell with different light power on algae grown cathode were compared. Results showed that microbial fuel cell with 6 and 12W power of light always produced higher voltage and power density than with 18 and 26W. Similarly, microbial fuel cell with 6 and 12W of light power always displayed higher Coulombic efficiency and specific power than the one with 18 and 26W. The results also showed that microbial fuel cell with covered anodic chamber always displayed higher voltage, power density, Coulombic efficiency and specific power than the one without covered anodic chamber. Binary quadratic equations can be used to express the relationships between the light power and the voltage, power density, Coulombic efficiency and specific power. Although lower power of light on algae grown cathode and covering anodic chamber will increase system's electricity production, they will not significantly reduce its internal resistance. PMID:22929741

Juang, D F; Lee, C H; Hsueh, S C

2012-07-21

125

Detailed structural and quantitative analysis reveals the spatial organization of the cell walls of in vivo grown Mycobacterium leprae and in vitro grown Mycobacterium tuberculosis.  

PubMed

The cell wall of mycobacteria consists of an outer membrane, analogous to that of gram-negative bacteria, attached to the peptidoglycan (PG) via a connecting polysaccharide arabinogalactan (AG). Although the primary structure of these components is fairly well deciphered, issues such as the coverage of the PG layer by covalently attached mycolates in the outer membrane and the spatial details of the mycolic acid attachment to the arabinan have remained unknown. It is also not understood how these components work together to lead to the classical acid-fast staining of mycobacteria. Because the majority of Mycobacterium tuberculosis bacteria in established experimental animal infections are acid-fast negative, clearly cell wall changes are occurring. To address both the spatial properties of mycobacterial cell walls and to begin to study the differences between bacteria grown in animals and cultures, the cell walls of Mycobacterium leprae grown in armadillos was characterized and compared with that of M. tuberculosis grown in culture. Most fundamentally, it was determined that the cell wall of M. leprae contained significantly more mycolic acids attached to PG than that of in vitro grown M. tuberculosis (mycolate:PG ratios of 21:10 versus 16:10, respectively). In keeping with this difference, more arabinogalactan (AG) molecules, linking the mycolic acids to PG, were found. Differences in the structures of the AG were also found; the AG of M. leprae is smaller than that of M. tuberculosis, although the same basic structural motifs are retained. PMID:21555513

Bhamidi, Suresh; Scherman, Michael S; Jones, Victoria; Crick, Dean C; Belisle, John T; Brennan, Patrick J; McNeil, Michael R

2011-05-09

126

Performance Degradation of Czochralski-Grown Silicon Solar Cells by Means of Current Injection  

Microsoft Academic Search

Performance degradation of Czochralski-grown silicon (Cz-Si) solar cells caused by forward bias voltage application has been investigated. Because of the similarity to light-induced degradation, comparative experiments are carried out on the phenomena. Cell performance decay time evaluations reveal that current injection has a weaker effect on the degradation than illumination in the low-injection region. A difference in the energy of

Hiroshi Hashigami; Marwan Dhamrin; Tadashi Saitoh

2002-01-01

127

Tensile forces enhance prostaglandin E synthesis in osteoblastic cells grown on collagen ribbons  

Microsoft Academic Search

Summary  An experimental system has been developed to examine the prostaglandin (PG) production induced by tensile mechanical forces\\u000a in bone cells cultured on collagen ribbons. Fetal rat calvaria cells (osteoblast-enriched) were grown on collagen ribbons.\\u000a The collagen ribbons were stretched under culture conditions in a machine that recorded force and displacement. Repeated stretching\\u000a of the collagen ribbons (8 times, 5–10%, over

Chih-Ko Yeh; Gideon A. Rodan

1984-01-01

128

Comparison of Planktonic and Biofilm Cultures of Pseudomonas fluorescens DSM 8341 Cells Grown on Fluoroacetate?  

PubMed Central

Comparisons between the physiological properties of Pseudomonas fluorescens biofilm cells grown in a tubular biofilm reactor and planktonic cells grown in a chemostat were performed. Fluoroacetate was the sole carbon source for all experiments. The performance of cells was assessed using cell cycle kinetics and by determining specific fluoroacetate utilization rates. Cell cycle kinetics were studied by flow cytometry in conjunction with the fluorescent stain propidium iodide. Determination of the DNA content of planktonic and biofilm cultures showed little difference between the two modes of growth. Cultures with comparable specific glycolate utilization rates had similar percentages of cells in the B phase of the cell cycle, indicating similar growth rates. Specific fluoroacetate utilization rates showed the performance of planktonic cells to be superior to that of biofilm cells, with more fluoroacetate utilized per cell at similar specific fluoroacetate loading rates. A consequence of this decreased biofilm performance was the accumulation of glycolate in the effluent of biofilm cultures. This accumulation of glycolate was not observed in the effluent of planktonic cultures. Spatial stratification of oxygen within the biofilm was identified as a possible explanation for the overflow metabolism of glycolate and the decreased performance of the biofilm cells.

Heffernan, Barry; Murphy, Cormac D.; Casey, Eoin

2009-01-01

129

The growth and morphology of FRTL-5 thyroid epithelial cells grown as multicellular spheroids in vitro  

Microsoft Academic Search

Summary  FRTL-5 cells, a diploid line of differentiated rat thyroid epithelial cells, have been grown as multicellular spheroids in\\u000a spinner culture. Spheroids were initiated by seeding FRTL-5 cells either into Lab-Tek dishes or culture flasks with a 0.5%\\u000a agar base. Thyroid stimulating hormone (TSH, >1.0 mU\\/ml) was required for initial cell aggregation and spheroid growth. After\\u000a 1 wk cellular aggregates were

R. Timothy Mulcahy; Wayne A. Rosenkrans; David P. Penney; Robert A. Cooper

1985-01-01

130

Alteration of ATPase activity and duplex DNA in corneal cells grown in high glucose media.  

PubMed

An investigation was made on the possible effects of high levels (450 mg/dl) of glucose on the activities of Na,K-ATPase [E.C. (Enzyme Commission) 3.6.1.37] and Mg-ATPase (E.C. 3.6.1.4) in plasma membrane preparations of bovine corneal endothelial cells grown in tissue culture. The activities of these enzymes were compared with the activities of the same enzymes from cells grown in low or "fasting" levels (90 mg/dl) of glucose. All activities were assayed from cells that were secondary cultures (15-25 days after trypsinization). The results indicated a 76% decrease in activity for Na,K-ATPase (0.04 units in high glucose vs. 0.17 units in low glucose). The activity for Mg-ATPase also decreased by 33% (0.24 units in high glucose vs. 0.36 units in low glucose). A t-test for significance indicated that the loss of activity in both enzymes was highly significant (p < 0.001) in the high glucose media. Assays for ATPase activity of plasma membranes were also made directly in high glucose after removal of the membranes from cells grown in low-glucose media. However, those membrane ATPases showed no significant decrease in activity. Tests for DNA damage of cells grown in the presence of high levels of glucose indicated a 15.5% change (decrease) in the amount of double-stranded DNA remaining after alkali treatment. This change was highly significant also (p < 0.001). These data suggest that the diabetic state may negatively affect membrane-bound ATPases of the corneal endothelium and further point to the possibility of an altered synthetic rate of ATPase polypeptides as a result of DNA damage. PMID:8393396

Whikehart, D R; Montgomery, B; Angelos, P; Sorna, D

1993-07-01

131

Morphological and ultrastructural changes in vegetative cells and heterocysts of Anabaena variabilis grown with fructose.  

PubMed Central

The morphology and ultrastructure of Anabaena variabilis grown in medium with and without 40 mM fructose were compared. Vegetative cells and young heterocysts in fructose-supplemented medium were significantly larger, were filled with glycogen granules, and had fewer thylakoids. Developing heterocysts contained large numbers of glycogen granules well into mature stages, and envelope formation was precocious. As heterocysts enlarged in fructose medium, their shape became more broadly oblong compared with the more rectangular heterocysts in fructose-free medium. Images

Lang, N J; Krupp, J M; Koller, A L

1987-01-01

132

Sensitivity of Candida Albicans Biofilm Cells Grown on Denture Acrylic to Antifungal Proteins and Chlorhexidine  

PubMed Central

Objectives Candida albicans cells form biofilms on polymeric surfaces of dentures and other prostheses introduced into the oral cavity. Many biofilm microorganisms exhibit resistance to antimicrobial agents; C. albicans cells may also develop resistance to naturally-occurring antifungal peptides in human saliva including histatins (Hsts) and defensins (hBDs). Therefore, we evaluated Hst 5 activity on C. albicans biofilm cells compared to planktonic cells and measured whether surface treatment of denture acrylic with Hst 5, hBD-3, or chlorhexidine gluconate could inhibit in vitro biofilm development. Methods Acrylic disks were preconditioned with 500 ?l saliva for 30 min, and inoculated with C. albicans cells (106 cells/ml) for 1 h, at 37 °C. Non-adherent cells were removed by washing and disks and were incubated in YPD growth medium for 24, 48, and 72 h at 37 °C. Candidacidal assays were performed on 48-hour-biofilms and on planktonically-grown cells using Hst 5 (15.5 ?M, 31.25 ?M, 62 ?M). Cell adhesion was compared on disks pre-coated with 0.12% chlorhexidine gluconate, 50 ?M Hst 5, or 0.6 ?M hBD-3 after 24 h, 48 h, and 72 h growth. Results No significant difference was observed in sensitivity to Hst 5 of biofilm cells compared to planktonic cells (p > 0.05). Pre-coating disks with hBD-3 did not inhibit biofilm development; however, Hst 5 significantly inhibited biofilm development at 72 h, while 0.12% chlorhexidine significantly inhibited biofilm development at all time intervals (p < 0.05). Conclusions C. albicans biofilm cells grown on denture acrylic are sensitive to killing by Hst 5. Surface coating acrylic with chlorhexidine or Hst 5 effectively inhibits biofilm growth and has potential therapeutic application.

Pusateri, Christopher R.; Monaco, Edward A.; Edgerton, Mira

2009-01-01

133

Epitaxial Crystal Silicon Absorber Layers and Solar Cells Grown at 1.8 Microns per Minute  

SciTech Connect

We have grown device-quality epitaxial silicon thin films at growth rates up to 1.85 {micro}m/min, using hot-wire chemical vapor deposition from silane, at substrate temperatures below 750 C. At these rates, which are more than 30 times faster than those used by the amorphous and nanocrystalline Si industry, capital costs for large-scale solar cell production would be dramatically reduced, even for cell absorber layers up to 10 {micro}m thick. We achieved high growth rates by optimizing the three key parameters: silane flow, depletion, and filament geometry, based on our model developed earlier. Hydrogen coverage of the filament surface likely limits silane decomposition and growth rate at high system pressures. No considerable deterioration in PV device performance is observed when grown at high rate, provided that the epitaxial growth is initiated at low rate. A simple mesa device structure (wafer/epi Si/a-Si(i)/a-Si:H(p)/ITO) with a 2.3 {micro}m thick epitaxial silicon absorber layer was grown at 0.7 {micro}m/min. The finished device had an open-circuit voltage of 0.424 V without hydrogenation treatment.

Bobela, D. C.; Teplin, C. W.; Young, D. L.; Branz, H. M.; Stradins, P.

2011-01-01

134

Manipulation of Fatty Acid Composition in Animal Cells Grown in Culture*  

PubMed Central

The fatty acid composition of animal cells cultured in serum-free medium can be manipulated when the synthesis of endogenous fatty acids is inhibited by a biotin analog and fatty acids are supplied in the medium as detergent esters of Tween. When mouse LM cells were grown in medium supplemented with Tween-19:0 (an ester of Tween and nonadecanoic acid), odd chain fatty acid content of cellular phospholipids and neutral lipids increased from 1% to 75%. Concurrently, the saturated fatty acid content increased from 27% to 85%. Similar alterations in fatty acid content have been observed when BHK21 cells are subjected to the same enrichment regime. The ability to control the fatty acid composition of cultured animal cells is a prerequisite to investigations into the role of the membrane lipid physical state in processes unique to these cells. Images

Wisnieski, Bernadine J.; Williams, Robert E.; Fox, C. Fred

1973-01-01

135

Light-triggered organization of the stigma in dark-grown nondividing cells of Euglena gracilis.  

PubMed

Dark-grown cells of Euglena gracilis Klebs var. bacillaris Cori contain amorphous stigma material. When these cells are placed on resting medium for 3 days in darkness, the cells cease division; the organization of a normal stigma from the amorphous material requires continuous illumination for 72-96 hr. We have now found that if dark-grown cells are placed on resting medium for 8 days, a 40-min light pulse is sufficient to cause normal organization of the stigma in a subsequent 72-hr dark period. Thus stigma development is light-dependent at 3 days of resting but becomes light-triggered at 8 days. Other examples of light-triggered phenomena in Euglena are discussed and a model based on turnover of protein molecules repressing development that are ordinarily removed by exposure to light is presented; it is suggested that as the cells become more starved their ability to replace repressor molecules removed by light becomes limited and the system thereby becomes light-triggered rather than light-dependent. PMID:3938992

Osafune, T; Alhadeff, M; Schiff, J A

136

Influence of Cell Volume in Multicell Transplant Flats on the Growth of Organically Grown Seedlings of Medicinal Plants  

Microsoft Academic Search

Multi-cell transplant flats were compared to determine the influence of cell volume on the growth and nutritional condition of seedlings of angelica (Angelica archangelica L.), horehound (Marrubium vulgare L.) and thyme (Thymus vulgaris L.) grown in organic media. Plant growth and mineral concentration generally increased with cell volume, though the effect varied with different plant species. An increase in cell

E. Herrera; N. Tremblay; A. Gosselin

1996-01-01

137

Comparison of saftey and immunogenicity of purified chick embryo cell rabies vaccine (PCECV) and purified vero cell rabies vaccine (PVRV) using the Thai Red Cross intradermal regimen at a dose of 0.1 ML.  

PubMed

Intradermal (ID) vaccination with modern cell culture rabies vaccines is a means to significantly reduce the cost of post-exposure prophylaxis as compared to intramuscular vaccination. In this study we evaluated the efficacy, immunogenicity and tolerability of PCECV and PVRV administered ID in doses of 0.1 mL per site according to the 2-site Thai Red Cross (TRC) regimen. Patients with WHO category III exposure to suspect or laboratory proven rabid animals were administered either PCECV (n = 58) or PVRV (n = 52) ID at a dose of 0.1 mL per site at two sites on days 0, 3 and 7 and at one site on days 30 and 90. Serum samples were withdrawn on days 0, 14, 30, 90 and 180 and rabies virus neutralizing antibody (RVNA) titers were determined by rapid fluorescent focus inhibition test (RFFIT). Patients who were exposed to laboratory confirmed rabid animals were followed up for one year after exposure. All 110 patients developed RVNA titers above 0.5 IU/mL by day 14. Adequate titers >0.5 IU/mL were maintained up to day 180. Both vaccines induced equivalent RVNA titers at all time points and were well tolerated. Five subjects who were bitten by laboratory confirmed rabid dogs were alive and healthy one year after exposure. As demonstrated, PCECV and PVRV are both immunogenic, efficacious and well tolerated when administered in the TRC post-exposure prophylaxis regimen in ID doses of 0.1 mL as recommended by WHO guidelines. The use of PCECV in this regimen may prove more economical in developing countries like India. PMID:17035734

Madhusudana, Shampur N; Sanjay, Thitamaranahalli V; Mahendra, Bangalore J; Sudarshan, Mysore K; Narayana, Doddabele H Ashwath; Giri, Anand; Muhamuda, Kader; Ravi, Vasanthapuram; Vakil, Hoshang B; Malerczyk, Cladius

138

Binding of metals by cell walls of Cunninghamella blakesleeana grown in the presence of copper or cobalt  

Microsoft Academic Search

The binding of metals by cell walls isolated from Cunninghamella blakesleeana grown in the presence of inhibitory concentration of Cu or Co and which had altered chemical compositions was compared with the binding by control cell walls. The Co-cell walls, which had higher contents of phosphate and chitosan, bound more Cu and Co. Although the Vmax for Cu and Co

G. Venkateswerlu; G. Stotzky

1989-01-01

139

Mesenchymal traits are selected along with stem features in breast cancer cells grown as mammospheres.  

PubMed

Increasing evidence indicates that invasive properties of breast cancers rely on gain of mesenchymal and stem features, which has suggested that the dual targeting of these phenotypes may represent an appealing therapeutic strategy. It is known that the fraction of stem cells can be enriched by culturing breast cancer cells as mammospheres (MS), but whether these pro-stem conditions favor also the expansion of cells provided of mesenchymal features is still undefined. In the attempt to shed light on this issue, we compared the phenotypes of a panel of 10 breast cancer cell lines representative of distinct subtypes (luminal, HER2-positive, basal-like and claudin-low), grown in adherent conditions and as mammospheres. Under MS-proficient conditions, the increment in the fraction of stem-like cells was associated to upregulation of the mesenchymal marker Vimentin and downregulation of the epithelial markers expressed by luminal cells (E-cadherin, KRT18, KRT19, ESR1). Luminal cells tended also to upregulate the myoepithelial marker CD10. Taken together, our data indicate that MS-proficient conditions do favor mesenchymal/myoepithelial features, and indicate that the use of mammospheres as an in vitro tumor model may efficiently allow the exploitation of therapeutic approaches aimed at targeting aggressive tumors that have undergone epithelial-to-mesenchymal transition PMID:23095640

Borgna, Silvia; Armellin, Michela; di Gennaro, Alessandra; Maestro, Roberta; Santarosa, Manuela

2012-10-24

140

Mesenchymal traits are selected along with stem features in breast cancer cells grown as mammospheres  

PubMed Central

Increasing evidence indicates that invasive properties of breast cancers rely on gain of mesenchymal and stem features, which has suggested that the dual targeting of these phenotypes may represent an appealing therapeutic strategy. It is known that the fraction of stem cells can be enriched by culturing breast cancer cells as mammospheres (MS), but whether these pro-stem conditions favor also the expansion of cells provided of mesenchymal features is still undefined. In the attempt to shed light on this issue, we compared the phenotypes of a panel of 10 breast cancer cell lines representative of distinct subtypes (luminal, HER2-positive, basal-like and claudin-low), grown in adherent conditions and as mammospheres. Under MS-proficient conditions, the increment in the fraction of stem-like cells was associated to upregulation of the mesenchymal marker Vimentin and downregulation of the epithelial markers expressed by luminal cells (E-cadherin, KRT18, KRT19, ESR1). Luminal cells tended also to upregulate the myoepithelial marker CD10. Taken together, our data indicate that MS-proficient conditions do favor mesenchymal/myoepithelial features, and indicate that the use of mammospheres as an in vitro tumor model may efficiently allow the exploitation of therapeutic approaches aimed at targeting aggressive tumors that have undergone epithelial-to-mesenchymal transition.

Borgna, Silvia; Armellin, Michela; di Gennaro, Alessandra; Maestro, Roberta; Santarosa, Manuela

2012-01-01

141

Enhanced chemoresistance of squamous carcinoma cells grown in 3D cryogenic electrospun scaffolds.  

PubMed

It is critically important to study head and neck squamous cell carcinoma tumorigenic mechanisms in order to gain a better understanding of tumor development, progression, and treatment. Unfortunately, a representative three-dimensional (3D) model for these evaluations has yet to be developed. The purpose of this study was to replicate tumor extracellular matrix (ECM) morphology utilizing electrospinning technology. First, the tumor ECM was evaluated by decellularizing tumor samples and analyzing the fibrous structure of the ECM by scanning electron microscopy. Cryogenic electrospun silk scaffolds were then fabricated to mimic the tumor ECM, and were found to be similar in fiber orientation and fiber dimensions to the native tumor ECM. Tumor cells were cultured on these ECM mimicking scaffolds and compared to an in vivo model of the same derivative human tumor in terms of proliferation and differentiation. The tumor cells in the 3D model show similar phenotypes to those found in vivo, contrasting to the same cells grown in two-dimensional (2D) culture. The sensitivity of the tumor cells to paclitaxel was compared between 2D culture and 3D culture. The results indicate that increased drug concentrations, orders of magnitude higher than the IC90 for 2D culture, had minimal effects on HN12 cell viability in the 3D model. In conclusion, an in vitro tumor model has been developed that will allow for a better understanding of tumor biology and aid chemotherapeutic drug development and accurate evaluation of drug efficacy. PMID:24057893

Bulysheva, Anna A; Bowlin, Gary L; Petrova, Stella P; Yeudall, W Andrew

2013-09-20

142

Effect of illumination conditions on Czochralski-grown silicon solar cell degradation  

NASA Astrophysics Data System (ADS)

The substitutional B-interstitial O-related defects induced under an illumination, specific to B-doped Czochralski-grown silicon (Cz-Si), results in a solar cell efficiency loss of up to 3%. For a fundamental interpretation, the relationship between the solar cell performance and the minority-carrier lifetime degradation, and influence of the illumination conditions were investigated. A simulation of the cell performance degradation clearly represented that the degradation was explained as a result of the carrier diffusion length degradation. From a spectroscopic illumination investigation, the degradation was found to be independent of the stress-light wavelength. A blue light illumination on a solar cell resulted in the red response degradation, suggesting that the injected carriers activated the defect in the bulk. However, the correlation between carrier injection level and the cell performance decay time was nonlinear. The observed decay times were almost independent of the illumination intensity in the range of 1 to 100 mW/cm2. This trend appeared more significantly on cells with a higher base resistivity. From the experimental results, the role of excess carriers in the defect activation was discussed.

Hashigami, Hiroshi; Itakura, Yu; Saitoh, Tadashi

2003-04-01

143

Differential response in downstream processing of CHO cells grown under mild hypothermic conditions.  

PubMed

The manufacture of complex therapeutic proteins using mammalian cells is well established, with several strategies developed to improve productivity. The application of sustained mild hypothermic conditions during culture has been associated with increases in product titre and improved product quality. However, despite associated cell physiological effects, very few studies have investigated the impact on downstream processing (DSP). Characterisation of cells grown under mild hypothermic conditions demonstrated that the stationary phase was prolonged by delaying the onset of apoptosis. This enabled cells to maintain viability for extended periods of time and increase volumetric productivity from 0.74 g L(-1) to 1.02 g L(-1) . However, host cell proteins, measured by ELISA, increased by ~50%, attributed to the extended time course and higher peak and harvest cell densities. The individual components making up this impurity, as determined by SELDI-TOF MS and 2D-PAGE, were shown to be largely comparable. Under mild hypothermic conditions cells were less shear sensitive than those maintained at 37°C, enhancing the preliminary primary recovery step. Adaptive changes in membrane fluidity were further investigated by adopting a pronounced temperature shift immediately prior to primary recovery and the improvement observed suggests that such a strategy may be implementable when shear sensitivity is of concern. Early and late apoptotic cells were particularly susceptible to shear, at either temperature, even under the lowest shear rate investigated. These findings demonstrate the importance of considering the impact of cell culture strategies and cell physiology on DSP, by implementing a range of experimental methods for process characterisation. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 2013. PMID:23509041

Tait, A S; Tarrant, R D R; Velez-Suberbie, M L; Spencer, D I R; Bracewell, D G

2013-03-19

144

Differential response in downstream processing of CHO cells grown under mild hypothermic conditions.  

PubMed

The manufacture of complex therapeutic proteins using mammalian cells is well established, with several strategies developed to improve productivity. The application of sustained mild hypothermic conditions during culture has been associated with increases in product titer and improved product quality. However, despite associated cell physiological effects, very few studies have investigated the impact on downstream processing (DSP). Characterization of cells grown under mild hypothermic conditions demonstrated that the stationary phase was prolonged by delaying the onset of apoptosis. This enabled cells to maintain viability for extended periods and increase volumetric productivity from 0.74 to 1.02 g L(-1) . However, host cell proteins, measured by ELISA, increased by ?50%, attributed to the extended time course and higher peak and harvest cell densities. The individual components making up this impurity, as determined by SELDI-TOF MS and 2D-PAGE, were shown to be largely comparable. Under mild hypothermic conditions, cells were less shear sensitive than those maintained at 37°C, enhancing the preliminary primary recovery step. Adaptive changes in membrane fluidity were further investigated by adopting a pronounced temperature shift immediately prior to primary recovery and the improvement observed suggests that such a strategy may be implementable when shear sensitivity is of concern. Early and late apoptotic cells were particularly susceptible to shear, at either temperature, even under the lowest shear rate investigated. These findings demonstrate the importance of considering the impact of cell culture strategies and cell physiology on DSP, by implementing a range of experimental methods for process characterization. PMID:23636936

Tait, Andrew S; Tarrant, Richard D R; Velez-Suberbie, M Lourdes; Spencer, Daniel I R; Bracewell, Daniel G

2013-05-02

145

Quantitative analysis of cell walls of nutritionally variant streptococci grown under various growth conditions.  

PubMed Central

Strains of nutritionally variant streptococci are usually isolated from patients with subacute bacterial endocarditis. Only recently have these strains been subdivided into three serotypes; however, no group-specific antigen has been described. To understand the immunochemical basis for the serology of these microorganisms as well as set the groundwork for adherence studies, quantitative analysis of the cell walls of nutritionally variant streptococci was undertaken. The bacteria were grown in semisynthetic medium or pyridoxal-supplemented Todd-Hewitt broth and harvested during the exponential or stationary phase. Cell walls were isolated and analyzed for amino sugars, sugars, polyalcohols, amino acids, and phosphorus by gas chromatography, high-pressure liquid chromatography, or colorimetric assays. The peptidoglycans of the cell walls of the prototype strains from the three serotypes were representative of other streptococcal cell walls, including the presence of alanine as the possible cross-bridge. The composition of the peptidoglycan was similar for all three strains and included a decreased concentration of peptidoglycan in their cell walls during the stationary phase. Glucosamine, glucose, galactose, ribitol, and a small amount of rhamnose were found in each of the cell wall polysaccharides. Galactosamine was only found in serotype II and III cell walls and might be responsible for the previously described cross-reaction between these strains. The concentration of the other sugars and amino sugars varied in each of the cell wall preparations, depending on the growth conditions. Finally, all three strains expressed both ribitol and phosphorus in their cell walls, characteristic of the presence of a ribitol teichoic acid. Therefore the cell wall composition of the nutritionally variant streptococci varies depending on the growth conditions, and their composition appears similar to that of strains of Streptococcus mitis.

van de Rijn, I

1985-01-01

146

Highly parallel introduction of nucleic acids into mammalian cells grown in microwell arrays.  

PubMed

High-throughput cell-based screens of genome-size collections of cDNAs and siRNAs have become a powerful tool to annotate the mammalian genome, enabling the discovery of novel genes associated with normal cellular processes and pathogenic states, and the unravelling of genetic networks and signaling pathways in a systems biology approach. However, the capital expenses and the cost of reagents necessary to perform such large screens have limited application of this technology. Efforts to miniaturize the screening process have centered on the development of cellular microarrays created on microscope slides that use chemical means to introduce exogenous genetic material into mammalian cells. While this work has demonstrated the feasibility of screening in very small formats, the use of chemical transfection reagents (effective only in a subset of cell lines and not on primary cells) and the lack of defined borders between cells grown in adjacent microspots containing different genetic material (to prevent cell migration and to aid spot location recognition during imaging and phenotype deconvolution) have hampered the spread of this screening technology. Here, we describe proof-of-principles experiments to circumvent these drawbacks. We have created microwell arrays on an electroporation-ready transparent substrate and established procedures to achieve highly efficient parallel introduction of exogenous molecules into human cell lines and primary mouse macrophages. The microwells confine cells and offer multiple advantages during imaging and phenotype analysis. We have also developed a simple method to load this 484-microwell array with libraries of nucleic acids using a standard microarrayer. These advances can be elaborated upon to form the basis of a miniaturized high-throughput functional genomics screening platform to carry out genome-size screens in a variety of mammalian cells that may eventually become a mainstream tool for life science research. PMID:20024036

Jain, Tilak; McBride, Ryan; Head, Steven; Saez, Enrique

2009-10-13

147

Enterotoxin production by Vibrio cholerae and Vibrio mimicus grown in continuous culture with microbial cell recycle.  

PubMed Central

We have examined the effect of complete cell recycle on the production of cholera toxin (CT) by Vibrio cholerae and CT-like toxin by Vibrio mimicus in continuous culture fermentations. Complete cell recycle was obtained by filtering culture fluids through Amicon hollow fibers with an exclusion limit of 100,000 daltons (H1P100-20) and returning the concentrated cell slurry to the fermentor. A single 1-liter laboratory fermentor system modified with this recycle loop was capable of producing over 20 liters of cell-free culture filtrate per day. Toxin production in this system was compared with yields obtained in traditional continuous cultures and in shake flask cultures. Yields of CT from V. cholerae 569B in the recycle fermentor were highest at the highest dilution rate employed (1.0 vol/vol per h). The use of complete cell recycle dramatically increased yields over those obtained in continuous culture and equaled those obtained in shake flasks. The concentration of CT in the filtrate was slightly less than half of that measured in culture fluids sampled at the same time. Similarly, V. mimicus 61892 grown in the presence of 50 micrograms of lincomycin per ml produced 280 ng of CT per ml in the recycle fermentor, compared with 210 ng/ml in shake flasks under optimal conditions. The sterile filtrate from this fermentation contained 110 ng/ml.

Spira, W M; Fedorka-Cray, P J

1983-01-01

148

PEDF and VEGF-A Output from Human Retinal Pigment Epithelial Cells Grown on Novel Microcarriers  

PubMed Central

Human retinal pigment epithelial (hRPE) cells have been tested as a cell-based therapy for Parkinson's disease but will require additional study before further clinical trials can be planned. We now show that the long-term survival and neurotrophic potential of hRPE cells can be enhanced by the use of FDA-approved plastic-based microcarriers compared to a gelatin-based microcarrier as used in failed clinical trials. The hRPE cells grown on these plastic-based microcarriers display several important characteristics of hRPE found in vivo: (1) characteristic morphological features, (2) accumulation of melanin pigment, and (3) high levels of production of the neurotrophic factors pigment epithelium-derived factor (PEDF) and vascular endothelial growth factor-A (VEGF-A). Growth of hRPE cells on plastic-based microcarriers led to sustained levels (>1?ng/ml) of PEDF and VEGF-A in conditioned media for two months. We also show that the expression of VEGF-A and PEDF is reciprocally regulated by activation of the GPR143 pathway. GPR143 is activated by L-DOPA (1??M) which decreased VEGF-A secretion as opposed to the previously reported increase in PEDF secretion. The hRPE microcarriers are therefore novel candidate delivery systems for achieving long-term delivery of the neuroprotective factors PEDF and VEGF-A, which could have a value in neurodegenerative conditions such as Parkinson's disease.

Falk, Torsten; Congrove, Nicole R.; Zhang, Shiling; McCourt, Alexander D.; Sherman, Scott J.; McKay, Brian S.

2012-01-01

149

Survival in seawater of Escherichia coli cells grown in marine sediments containing glycine betaine.  

PubMed Central

Considering both the protective effect of glycine betaine (GB) on enteric bacteria grown at high osmolarity and the possible presence of GB in marine sediments, we have analyzed the survival, in nutrient-free seawater, of Escherichia coli cells incubated in sediments supplemented with GB or not supplemented and measured the efficiency of GB uptake systems and the expression of proP and proU genes in both seawater and sediments. We did this by using strains harboring proP-lacZ and proU-lacZ operon or gene fusions. We found that the uptake of GB and the expression of both proP and proU were very weak in seawater. The survival ability of cells in seawater supplemented with GB was a linear function of GB concentration, although the overall protection by the osmolyte was low. In sediments, proP expression was weak and GB uptake and proU expression were variable, possibly depending on the availability of organic nutrients. In a sediment with a high total organic carbon content, GB uptake was very high and proU expression was enhanced; cells previously incubated in this sediment showed a higher resistance to decay in seawater. GB might therefore play a significant role in the long-term maintenance of enteric bacterial cells in some marine sediments.

Gauthier, M J; Le Rudulier, D

1990-01-01

150

Electrochemically grown ZnO nanorods for hybrid solar cell applications  

SciTech Connect

A hybrid solar cell is designed and proposed as a feasible and reasonable alternative, according to acquired efficiency with the employment of zinc oxide (ZnO) nanorods and ZnO thin films at the same time. Both of these ZnO structures were grown electrochemically and poly(3-hexylthiophene):phenyl-C61-butyric acid methyl ester; (P3HT:PCBM) was used as an active polymer blend, which was found to be compatible to prepared indium-tin-oxide (ITO) substrate base. This ITO base was introduced with mentioned ZnO structure in such a way that, the most efficient configuration was optimized to be ITO/ZnO film/ZnO nanorod/P3HT: PCBM/Ag. Efficiency of this optimized device is found to be 2.44%. All ZnO works were carried out electrochemically, that is indeed for the first time and at relatively lower temperatures. (author)

Hames, Yakup [Department of Electrical-Electronics Engineering, Mustafa Kemal University, 31040 Hatay (Turkey); Alpaslan, Zuehal; Koesemen, Arif; San, Sait Eren; Yerli, Yusuf [Department of Physics, Gebze Institute of Technology, 41400 Gebze (Turkey)

2010-03-15

151

Apical and basolateral endocytosis in Madin-Darby canine kidney (MDCK) cells grown on nitrocellulose filters.  

PubMed Central

Madin-Darby canine kidney (MDCK) cells (strain I) grown on 0.45 micron pore size nitrocellulose filters formed monolayers which were highly polarized and had high transepithelial electrical resistance (greater than 3000 ohm X cm2). Morphometric analysis showed that the area of the basolateral surface domain was 7.6 times larger than that of the apical. The uptake of fluid-phase markers [3H]inulin and horseradish peroxidase (HRP) was studied from the apical and the basal side of the monolayer. Uptake of [3H]inulin was biphasic and the rate during the first 40 min corresponded to a fluid phase uptake of 20.5 X 10(-8) nl/min per cell from the basolateral side, and 1.0 X 10(-8) nl/min per cell from the apical side. Electron micrographs of the monolayers after HRP uptake showed that the marker was rapidly delivered into endosome-like vesicles and into multivesicular bodies. No labelling of the Golgi complex could be observed during 2 h of uptake. Evidence was obtained for the transport of fluid phase markers across the cell. HRP and fluorescein isothiocyanate-dextran crossed the monolayers in either direction at a rate corresponding to approximately 3 X 10(-8) nl of fluid/min/cell. Adding the transcytosis rate to the rate of fluid accumulation into the cell yielded a total basolateral endocytic rate which was 6-fold greater than the apical rate. When the uptake rates were normalized for membrane area the apical and basolateral endocytic rates were about equal per unit cell surface area. Images Fig. 1. Fig. 2. Fig. 4. Fig. 5. Fig. 6. Fig. 7. Fig. 8. Fig. 1.

von Bonsdorff, C H; Fuller, S D; Simons, K

1985-01-01

152

Spheroid Formation and Enhanced Cardiomyogenic Potential of Adipose-Derived Stem Cells Grown on Chitosan  

PubMed Central

Abstract Mesenchymal stem cells may differentiate into cardiomyocytes and participate in local tissue repair after heart injury. In the current study, rat adipose-derived adult stem cells (ASCs) grown on chitosan membranes were observed to form cell spheroids after 3 days. The cell seeding density and surface modification of chitosan with Arg-Gly-Asp–containing peptide had an influence on the sizes of ASC spheroids. In the absence of induction, these spheroids showed an increased level of cardiac marker gene expression (Gata4, Nkx2-5, Myh6, and Tnnt2) more than 20-fold versus cells on the tissue culture polystyrene (TCPS) dish. Induction by 5-azacytidine or p38 MAP kinase inhibitor (SB202190) did not further increase the cardiac marker gene expression of these spheroids. Moreover, the enhanced cardiomyogenic potential of the spheroids was highly associated with the chitosan substrates. When ASC spheroids were plated onto TCPS with either basal or cardiac induction medium for 9 days, the spheroids spread into a monolayer and the positive effect on cardiomyogenic marker gene expression disappeared. The possible role of calcium ion and the up-regulation of adhesion molecule P-selectin and chemokine receptor Cxcr4 were demonstrated in ASC spheroids. Applying these spheroids to the chronic myocardial infarction animal model showed better functional recovery versus single cells after 12 weeks. Taken together, this study suggested that the ASC spheroids on chitosan may form as a result of calcium ion signaling, and the transplantation of these spheroids may offer a simple method to enhance the efficiency of stem cell–based therapy in myocardial infarction.

Liu, Bing-Hsien; Yeh, Hsi-Yi; Lin, Yu-Chun; Wang, Min-Hsiung; Chen, David C.; Lee, Bo-Hua

2013-01-01

153

Membrane-DNA attachment sites in Streptococcus faecalis cells grown at different rates.  

PubMed Central

The M-band technique was used to assess the number of attachment points of DNA to the cell membrane of Streptococcus faecalis grown at three different rates. Cells were X irradiated in liquid nitrogen and then analyzed simultaneously for the introduction of double-strand breaks into the chromosome and the degree of removal of DNA from the cell membrane (M band). Consideration of the data from these experiments and of the topology of the bacterial chromosome resulted in a reevaluation of former quantitative models. Our results are consistent with a semiquantitative model in which the bacterial chromosome is organized around a core structure. We interpret our data to mean that the core is attached to the membrane and that the complexity of the core changes more drastically with growth rate than does the number of membrane-DNA attachment points. An alternative model in which RNA hybridizes with DNA containing single- and double-strand breaks is also discussed. In any event, the complexity of these interactions precludes a reliable estimate of the number of membrane-DNA attachment sites.

Parks, L C; Rigney, D; Daneo-Moore, L; Higgins, M L

1982-01-01

154

Differentiated lines of cells from rabbit renal medullary thick ascending limbs grown on amnion.  

PubMed

Previously we grew differentiated primary epithelial tissue cultures from rabbit renal medullary thick ascending limbs but were unable to subculture them into lines. Now, following the use of amnion as a support during the initial passages, two cell lines have grown from single fragments of medullary thick ascending limbs. Cells have now been in culture past 12 passages over more than 2 yr. On confluence they formed morphologically differentiated epithelial monolayers with polarization of the cells visible on electron microscopy. They had apical zonula occludens and microvilli, lateral cellular interdigitations, and basal membranes flat against the support. "Domes" often were visible when the epithelia formed on dishes, indicative of salt and water transport. Other functional differentiation in some passages of one line or the other included presence of Tamm-Horsfall protein (demonstrated by immunofluorescence) or transepithelial voltage oriented apical surface positive. Both the Tamm-Horsfall protein and the voltage are normally expressed by intact medullary thick ascending limbs and are characteristic of this particular nephron segment. PMID:3893152

Green, N; Algren, A; Hoyer, J; Triche, T; Burg, M

1985-07-01

155

Mycobacterium tuberculosis isolates grown under oxygen deprivation invade pulmonary epithelial cells.  

PubMed

Mycobacterium tuberculosis has the ability to adapt to and survive under different environmental conditions, including oxygen deprivation. To better understand the pathogenesis of M. tuberculosis, we studied the invasion of human alveolar (A549) and human bronchial (BBM) epithelial cell lines by M. tuberculosis isolates cultured under oxygen deprivation. We used isolates belonging to the Beijing and F15/LAM4/KZN families, isolates with unique DNA fingerprints and the laboratory strains H37Rv and H37Ra. We determined that: (1) M. tuberculosis bacilli grown under oxygen deprivation invade epithelial cells, (2) the invasion capacity of all 17 isolates differed, and (3) oxygen deprivation influenced the invasion capacity of these isolates. All isolates invaded the A549 more effectively than the BBM cells. Three of the F15/LAM4/KZN isolates, two of which had extensively drug resistance (XDR) profiles, were at least twice as invasive (?33%) as the most invasive Beijing isolate (15%) (P < 0.05). We conclude that for a more comprehensive understanding of the pathogenesis of M. tuberculosis, studies should include isolates that have been cultured under oxygen deprivation. PMID:22579984

Ashiru, Olubisi T; Pillay, Manormoney; Sturm, A Willem

2012-05-08

156

Improved lentiviral gene transfer into human embryonic stem cells grown in co-culture with murine feeder and stroma cells.  

PubMed

Genetic modification of human embryonic stem cells (hESCs) using biophysical DNA transfection methods are hampered by the very low single cell survival rate and cloning efficiency of hESCs. Lentiviral gene transfer strategies are widely used to genetically modify hESCs but limited transduction efficiencies in the presence of feeder or stroma cells present problems, particularly if vesicular stomatitis virus glycoprotein (VSV-G) pseudotyped viral particles are applied. Here, we investigated whether the recently described semen derived enhancer of virus infection (SEVI) and alternative viral envelope proteins derived from either Gibbon ape leukaemia virus (GALV) or feline leukaemia virus (RD114) are applicable for transducing hESCs during co-culture with feeder or stroma cells. Our first set of experiments demonstrates that SEVI has no toxic effect on murine or hESCs and that exposure to SEVI does not interfere with the pluripotency-associated phenotype. Focusing on hESCs, we were able to further demonstrate that SEVI increases the transduction efficiencies of GALV and RD114 pseudotyped lentiviral vectors. More importantly, aiming at targeted differentiation of hESCs into functional somatic cell types, GALV pseudotyped lentiviral particles could efficiently and exclusively transduce hESCs grown in co-culture with OP9-GFP stroma cells (which were often used to induce differentiation into haematopoietic derivatives). PMID:21812756

Wurm, Melanie; Gross, Benjamin; Sgodda, Malte; Ständker, Ludger; Müller, Thomas; Forssmann, Wolf-Georg; Horn, Peter A; Blasczyk, Rainer; Cantz, Tobias

2011-08-04

157

Eight-cell parthenotes originated from in vitro grown sheep preantral follicles.  

PubMed

We investigated the effect of the leukemia inhibitory factor (LIF) alone or in association with follicle-stimulating hormone (FSH) on the in vitro growth and antrum formation of sheep preantral follicles. To evaluate oocyte quality, parthenogenetic activation of the oocytes recovered from in vitro grown preantral follicles was performed. Preantral follicles >110 ?m in diameter were isolated and cultured for 18 days in basic medium either alone (control) or supplemented with LIF (10 or 50 ng/mL) in the absence or presence of FSH. Every 6 days the follicular survival, growth, and antrum formation were evaluated. When compared to control (P < .05), antrum formation was increased in follicles cultured in the presence of LIF10 and FSH. At the end of the culture, the oocytes underwent in vitro maturation (IVM); their viability and chromatin configuration were assessed. Although IVM was not affect by the treatments (P > .05), the numerically highest maturation rates (29.63%) were obtained when follicles were cultured in 50 ng/mL LIF (LIF50). Therefore, their oocytes were submitted to parthenogenetic activation; from which 58.3% of the mature oocytes resulted in 8-cell stage parthenotes. In conclusion, although LIF10 + FSH increases antrum formation when compared to a nonsupplemented medium (minimum essential medium), oocytes from sheep preantral follicles are capable of growing and maturing in vitro independent of LIF addition to the medium, which resulted in the formation of 8-cell parthenotes. PMID:22562971

Luz, V B; Araújo, V R; Duarte, A B G; Celestino, J J H; Silva, T F P; Magalhães-Padilha, D M; Chaves, R N; Brito, I R; Almeida, A P; Campello, C C; Feltrin, C; Bertolini, M; Santos, R R; Figueiredo, J R

2012-05-04

158

Epoxidation of Short-Chain Alkenes by Resting-Cell Suspensions of Propane-Grown Bacteria  

PubMed Central

Sixteen new cultures of propane-utilizing bacteria were isolated from lake water from Warinanco Park, Linden, N.J. and from lake and soil samples from Bayway Refinery, Linden, N.J. In addition, 19 known cultures obtained from culture collections were also found to be able to grow on propane as the sole carbon and energy source. In addition to their ability to oxidize n-alkanes, resting-cell suspensions of both new cultures and known cultures grown on propane oxidize short-chain alkenes to their corresponding 1,2-epoxides. Among the substrate alkenes, propylene was oxidized at the highest rate. In contrast to the case with methylotrophic bacteria, the product epoxides are further metabolized. Propane and other gaseous n-alkanes inhibit the epoxidation of propylene. The optimum conditions for in vivo epoxidation are described. Results from inhibition studies indicate that a propane monooxygenase system catalyzes both the epoxidation and hydroxylation reactions. Experiments with cell-free extracts show that both hydroxylation and epoxidation activities are located in the soluble fraction obtained after 80,000 × g centrifugation.

Hou, Ching T.; Patel, Ramesh; Laskin, Allen I.; Barnabe, Nancy; Barist, Irene

1983-01-01

159

Radial junction amorphous silicon solar cells on PECVD-grown silicon nanowires.  

PubMed

Constructing radial junction hydrogenated amorphous silicon (a-Si:H) solar cells on top of silicon nanowires (SiNWs) represents a promising approach towards high performance and cost-effective thin film photovoltaics. We here develop an all-in situ strategy to grow SiNWs, via a vapour-liquid-solid (VLS) mechanism on top of ZnO-coated glass substrate, in a plasma-enhanced chemical vapour deposition (PECVD) reactor. Controlling the distribution of indium catalyst drops allows us to tailor the as-grown SiNW arrays into suitable size and density, which in turn results in both a sufficient light trapping effect and a suitable arrangement allowing for conformal coverage of SiNWs by subsequent a-Si:H layers. We then demonstrate the fabrication of radial junction solar cells and carry on a parametric study designed to shed light on the absorption and quantum efficiency response, as functions of the intrinsic a-Si:H layer thickness and the density of SiNWs. These results lay a solid foundation for future structural optimization and performance ramp-up of the radial junction thin film a-Si:H photovoltaics. PMID:22539188

Yu, Linwei; O'Donnell, Benedict; Foldyna, Martin; Roca i Cabarrocas, Pere

2012-04-27

160

Biotransformation of Hydroxylaminobenzene and Aminophenol by Pseudomonas putida 2NP8 Cells Grown in the Presence of 3Nitrophenol  

Microsoft Academic Search

Biotransformation products of hydroxylaminobenzene and aminophenol produced by 3-nitrophenol-grown cells of Pseudomonas putida 2NP8, a strain grown on 2- and 3-nitrophenol, were characterized. Ammonia, 2-aminophenol, 4-aminophenol, 4-benzoquinone, N-acetyl-4-aminophenol, N-acetyl-2-aminophenol, 2-amino- phenoxazine-3-one, 4-hydroquinone, and catechol were produced from hydroxylaminobenzene. Ammonia, N-acetyl-2-aminophenol, and 2-aminophenoxazine-3-one were produced from 2-aminophenol. All of these metabolites were also found in the nitrobenzene transformation medium, and this

JIAN-SHEN ZHAO; AJAY SINGH; XIAO-DONG HUANG; OWEN P. WARD

2000-01-01

161

Significant changes in cell and chloroplast development in young wheat leaves (Triticum aestivum cv Hereward) grown in elevated COâ  

Microsoft Academic Search

Cell and chloroplast development were characterized in young Triticum aestivum cv Hereward leaves grown at ambient (350 μL L⁻¹) or at elevated (650 μL L⁻¹) COâ. In elevated COâ, cell and chloroplast expansion was accelerated by 10 and 25%, respectively, in the first leaf of 7-d-old wheat plants without disruption to the leaf developmental pattern. Elevated COâ did not affect

Elizabeth J. Robertson; R. M. Leech

1995-01-01

162

Antioxidant activity of Haematococcus pluvialis cells grown in continuous culture as a function of their carotenoid and fatty acid content  

Microsoft Academic Search

The influence of culture conditions on the quality of Haematococcus pluvialis biomass is assessed. Continuously grown cells have been characterised with respect to their astaxanthin, fatty acid content,\\u000a and antioxidant activity and compared with those of non-growing haematocysts. Moderate limitation of nitrate availability\\u000a (1.7 mM) under continuous growth conditions favoured the production of reddish palmelloid cells whose extracts possessed antioxidant\\u000a activity

M. C. Cerón; M. C. García-Malea; J. Rivas; F. G. Acien; J. M. Fernandez; E. Del Río; M. G. Guerrero; E. Molina

2007-01-01

163

Comparative analysis of Cryptococcus neoformans acid-resistant particles generated from pigmented cells grown in different laccase substrates  

Microsoft Academic Search

Cryptococcus neoformans produces pigments in vitro in the presence of exogenous substrate. We characterized acid-resistant particles isolated from pigmented cells grown in l-dopa, methyl-dopa, (?)-epinephrine or (?)-norepinephrine. The goals of this study were to determine whether pigments made from each of these substrates were melanins and the consequences of pigmentation on related cell characteristics. The greatest yield of acid-resistant particles

Javier Garcia-Rivera; Helene C. Eisenman; Joshua D. Nosanchuk; Philip Aisen; Oscar Zaragoza; Tiffany Moadel; Ekaterina Dadachova; Arturo Casadevall

2005-01-01

164

Antrodia camphorata Grown on Germinated Brown Rice Suppresses Melanoma Cell Proliferation by Inducing Apoptosis and Cell Differentiation and Tumor Growth  

PubMed Central

Antrodia camphorata grown on germinated brown rice (CBR) was prepared to suppress melanoma development. CBR extracts were divided into hexane, EtOAc, BuOH, and water fractions. Among all the fractions, EtOAc fraction showed the best suppressive effect on B16F10 melanoma cell proliferation by CCK-8 assay. It also showed the increased cell death and the changed cellular morphology after CBR treatment. Annexin V-FITC/PI, flow cytometry, and western blotting were performed to elucidate anticancer activity of CBR. The results showed that CBR induced p53-mediated apoptotic cell death of B16F10. CBR EtOAc treatment increased melanin content and melanogenesis-related proteins of MITF and TRP-1 expressions, which supports its anticancer activity. Its potential as an anticancer agent was further investigated in tumor-xenografted mouse model. In melanoma-xenografted mouse model, melanoma tumor growth was significantly suppressed under CBR EtOAc fraction treatment. HPLC analysis of CBR extract showed peak of adenosine. In conclusion, CBR extracts notably inhibited B16F10 melanoma cell proliferation through the p53-mediated apoptosis induction and increased melanogenesis. These findings suggest that CBR EtOAc fraction can act as an effective anticancer agent to treat melanoma.

Song, Minjung; Park, Dong Ki; Park, Hye-Jin

2013-01-01

165

Antrodia camphorata Grown on Germinated Brown Rice Suppresses Melanoma Cell Proliferation by Inducing Apoptosis and Cell Differentiation and Tumor Growth.  

PubMed

Antrodia camphorata grown on germinated brown rice (CBR) was prepared to suppress melanoma development. CBR extracts were divided into hexane, EtOAc, BuOH, and water fractions. Among all the fractions, EtOAc fraction showed the best suppressive effect on B16F10 melanoma cell proliferation by CCK-8 assay. It also showed the increased cell death and the changed cellular morphology after CBR treatment. Annexin V-FITC/PI, flow cytometry, and western blotting were performed to elucidate anticancer activity of CBR. The results showed that CBR induced p53-mediated apoptotic cell death of B16F10. CBR EtOAc treatment increased melanin content and melanogenesis-related proteins of MITF and TRP-1 expressions, which supports its anticancer activity. Its potential as an anticancer agent was further investigated in tumor-xenografted mouse model. In melanoma-xenografted mouse model, melanoma tumor growth was significantly suppressed under CBR EtOAc fraction treatment. HPLC analysis of CBR extract showed peak of adenosine. In conclusion, CBR extracts notably inhibited B16F10 melanoma cell proliferation through the p53-mediated apoptosis induction and increased melanogenesis. These findings suggest that CBR EtOAc fraction can act as an effective anticancer agent to treat melanoma. PMID:23533475

Song, Minjung; Park, Dong Ki; Park, Hye-Jin

2013-02-25

166

Dark hexose metabolism by photoautotrophically and heterotrophically grown cells of the blue-green alga (Cyanobacterium) Nostoc sp. strain Mac.  

PubMed Central

Photoautotrophically grown cells of the blue-green alga (cyanobacterium) Nostoc sp. strain Mac assimilated and oxidized both glucose and fructose in the dark at different rates. The rate of fructose metabolism in these cells could be stimulated by casein hydrolysate, the effect being most pronounced at low sugar concentrations. This stimulation was not seen in cells grown heterotrophically in the dark, suggesting that it is a transitory phenomenon which disappears during the autotrophy-heterotrophy growth transition. The stimulation of fructose assimilation by casein hydrolysate was abolished by chloramphenicol or streptomycin, suggesting there are rate-limiting steps in protein biosynthesis in the dark that ultimately lead to inhibition of fructose uptake. Glucose metabolism did not show these phenomena, indicating there are differences in the metabolism of the two sugars.

Bottomley, P J; van Baalen, C

1978-01-01

167

Biotransformation of D-Limonene to (+) trans-Carveol by Toluene-Grown Rhodococcus opacus PWD4 Cells  

Microsoft Academic Search

yield was 94 to 97%. Toluene was found to be a strong competitive inhibitor of the D-limonene conversion. Glucose-grown cells did not form any trans-carveol from D-limonene. These results suggest that one of the enzymes involved in toluene degradation is responsible for this allylic monohydroxylation. Another toluene degrader (Rhodococcus globerulus PWD8) had a lower specific activity but was found to

WOUTER A. DUETZ; ANN H. M. FJALLMAN; SHUYU REN; CATHERINE JOURDAT; BERNARD WITHOLT

2001-01-01

168

Adhesion of oxide scales grown on ferritic stainless steels in solid oxide fuel cells temperature and atmosphere conditions  

Microsoft Academic Search

Adhesion of thermal oxide scales grown at 800°C on ferritic stainless steels F18TNb (AISI 441) and F18MT (AISI 444) proposed as interconnectors in solid oxide fuel cells (SOFCs) was investigated. The effect of oxidising atmosphere – synthetic air or 2% H2O in H2 as the representative cathode and anode atmosphere respectively – was considered. Using a room temperature tensile test

S. Chandra-Ambhorn; Y. Wouters; L. Antoni; F. Toscan; A. Galerie

2007-01-01

169

Expression of photosynthesis genes in the cyanobacteriumSynechocystis sp. PCC 6803:psaA-psaB andpsbA transcripts accumulate in dark-grown cells  

Microsoft Academic Search

We have cloned and sequenced thepsaA andpsaB genes from the unicellular cyanobacteriumSynechocystis sp. PCC 6803. These genes are arranged in tandem, are co-transcribed, and are highly homologous to thepsaA andpsaB genes previously characterized. RNA was isolated from light-grown cells, from cells put in total darkness with and without glucose, and from cells grown under light-activated heterotrophic growth (LAHG) conditions. Quantitation

Lawrence B. Smart; Lee McIntosh

1991-01-01

170

Influence of different yeast cell-wall mutants on performance and protection against pathogenic bacteria ( Vibrio campbellii) in gnotobiotically-grown Artemia  

Microsoft Academic Search

A selection of isogenic yeast strains (with deletion for genes involved in cell-wall synthesis) was used to evaluate their nutritional and immunostimulatory characteristics for gnotobiotically-grown Artemia. In the first set of experiments the nutritional value of isogenic yeast strains (effected in mannoproteins, glucan, chitin and cell-wall bound protein synthesis) for gnotobiotically-grown Artemia was studied. Yeast cell-wall mutants were always better

Siyavash Soltanian; Jean Dhont; Patrick Sorgeloos; Peter Bossier

2007-01-01

171

Estimating the cell density and invasive radius of three-dimensional glioblastoma tumor spheroids grown in vitro  

NASA Astrophysics Data System (ADS)

To gain insight into brain tumor invasion, experiments are conducted on multicellular tumor spheroids grown in collagen gel. Typically, a radius of invasion is reported, which is obtained by human measurement. We present a simple, heuristic algorithm for automated invasive radii estimation (AIRE) that uses local fluctuations of the image intensity. We then derive an analytical expression relating the image graininess to the cell density for a model imaging system. The result agrees with the experiment up to a multiplicative constant and thus describes a novel method for estimating the cell density from bright-field images.

Stein, Andrew M.; Nowicki, Michal O.; Demuth, Tim; Berens, Michael E.; Lawler, Sean E.; Chiocca, E. Antonio; Sander, Leonard M.

2007-08-01

172

Epitaxial Crystal Silicon Absorber Layers and Solar Cells Grown at 1.8 Microns per Minute: Preprint  

SciTech Connect

We have grown device-quality epitaxial silicon thin films at growth rates up to 1.8 ?m/min, using hot-wire chemical vapor deposition from silane at substrate temperatures below 750 degrees C. At these rates, which are more than 30 times faster than those used by the amorphous and nanocrystalline Si industry, capital costs for large-scale solar cell production would be dramatically reduced, even for cell absorber layers up to 10 ?m thick. We achieved high growth rates by optimizing the three key parameters: silane flow, depletion, and filament geometry, based on our model developed earlier. Hydrogen coverage of the filament surface likely limits silane decomposition and growth rate at high system pressures. No considerable deterioration in PV device performance is observed when grown at high rate, provided that the epitaxial growth is initiated at low rate. A simple mesa device structure (wafer/epi Si/a-Si(i)/a-Si:H(p)/ITO) with a 2.3 um epitaxial silicon absorber layer was grown at 700 nm/min. The finished device had an open-circuit voltage of 0.424 V without hydrogenation treatment.

Bobela, D. C.; Teplin, C. W.; Young, D. L.; Branz, H. M.; Stradins, P.

2011-07-01

173

Significant Changes in Cell and Chloroplast Development in Young Wheat Leaves (Triticum aestivum cv Hereward) Grown in Elevated CO2.  

PubMed Central

Cell and chloroplast development were characterized in young Triticum aestivum cv Hereward leaves grown at ambient (350 [mu]L L-1) or at elevated (650 [mu]L L-1) CO2. In elevated CO2, cell and chloroplast expansion was accelerated by 10 and 25%, respectively, in the first leaf of 7-d-old wheat plants without disruption to the leaf developmental pattern. Elevated CO2 did not affect the number of chloroplasts in relation to mesophyll cell size or the linear relationship between chloroplast number or size and mesophyll cell size. No major changes in leaf anatomy or in chloroplast ultrastructure were detected as a result of growth in elevated CO2, but there was a marked reduction in starch accumulation. In leaf sections fluorescently tagged antisera were used to visualize and quantitate the amount of cytochrome f, the [alpha]- and [beta]-subunits of the coupling factor 1 in ATP synthase, D1 protein of the photosystem II reaction center, the 33-kD protein of the extrinsic oxygen-evolving complex, subunit II of photosystem I, and ribulose-1,5-bisphosphate carboxylase/oxygenase. A significant finding was that in 10 to 20% of the mesophyll cells grown in elevated CO2 the 33-kD protein of the extrinsic oxygen-evolving complex of photosystem II and cytochrome f were deficient by 75%, but the other proteins accumulated normally.

Robertson, E. J.; Leech, R. M.

1995-01-01

174

Utilization of metabolic energy under saline conditions: changes in properties of ATP dependent enzymes in plant cells grown under saline conditions  

Microsoft Academic Search

The effect of growth in saline medium on the activity of two ATP utilizing enzymes was studied. Hexokinase in carrot (Daucus\\u000a carota L.) cells grown in suspension culture either in the absence or presence of 150 ml NaCl, and tonoplast H+-ATPase in tobacco (Nicotiana tabacum L. cv. Wisconsin 38) cells grown in suspension culture either in the absence of presence

M. Reuveni

1992-01-01

175

Improved guggulsterone production from sugars, precursors, and morphactin in cell cultures of Commiphora wightii grown in shake flasks and a bioreactor  

Microsoft Academic Search

Cell cultures of Commiphora wightii (Arnott.) Bhandari were grown in shake flasks and a bioreactor and an increase in guggulsterone accumulation up to 18 ?g\\u000a l?1 was recorded in cells grown in the production medium containing a combination of sucrose:glucose (4% total), precursors (phenylalanine,\\u000a pyruvic acid, xylose, and sodium acetate), morphactin, and 2iP. A yield of 10 g l?1 biomass and ?200 ?g

Meeta Mathur; K. G. Ramawat

2008-01-01

176

Glycosylation and biological activity of CAMPATH-1H expressed in different cell lines and grown under different culture conditions.  

PubMed

CAMPATH-1H (where CAMPATH is a trade mark of Wellcome group companies), a humanized IgG antibody used in the therapy of lymphoma, leukaemia and rheumatoid arthritis, has been expressed in Chinese hamster ovary, Y0 myeloma and NS0 myeloma cell lines. These engineered cell lines were grown under different culture conditions, and the antibody isolated and purified. N-Linked oligosaccharides, on the CH2 heavy chain region of the antibody, were isolated and analysed by hydrazinolysis, high-performance anion-exchange chromatography with pulsed amperometric detection, laser-desorption mass spectrometry and sequential exoglycosidase treatment. Both the glycosylation pattern and the biological activity of CAMPATH-1H, as measured by antibody-dependent cell-mediated cytotoxicity, were markedly affected by the cell line used to express the antibody. It is concluded that glycosylation of the antibody may be important in the clinical outcome of therapy. PMID:8720080

Lifely, M R; Hale, C; Boyce, S; Keen, M J; Phillips, J

1995-12-01

177

Composite electrodes made of Pt nanoparticles deposited on carbon nanotubes grown on fuel cell backings  

Microsoft Academic Search

Multiwalled carbon nanotubes (MWCNTs), with typical lengths of 20 ?m and diameters of 40 nm, have been grown directly on carbon paper backing. A sulfonic acid–silicate intermediate was used to deposit Pt particles on the MWCNTs in order to obtain an electrode that could be used in electrocatalysis. The electrical path between the Pt nanoparticles (1.2±0.3 nm in size) and

X. Sun; R. Li; D. Villers; J. P. Dodelet; S. Désilets

2003-01-01

178

mtDNA depletion confers specific gene expression profiles in human cells grown in culture and in xenograft  

PubMed Central

Background Interactions between the gene products encoded by the mitochondrial and nuclear genomes play critical roles in eukaryotic cellular function. However, the effects mitochondrial DNA (mtDNA) levels have on the nuclear transcriptome have not been defined under physiological conditions. In order to address this issue, we characterized the gene expression profiles of A549 lung cancer cells and their mtDNA-depleted ?0 counterparts grown in culture and as tumor xenografts in immune-deficient mice. Results Cultured A549 ?0 cells were respiration-deficient and showed enhanced levels of transcripts relevant to metal homeostasis, initiation of the epithelial-mesenchymal transition, and glucuronidation pathways. Several well-established HIF-regulated transcripts showed increased or decreased abundance relative to the parental cell line. Furthermore, growth in culture versus xenograft has a significantly greater influence on expression profiles, including transcripts involved in mitochondrial structure and both aerobic and anaerobic energy metabolism. However, both in vitro and in vivo, mtDNA levels explained the majority of the variance observed in the expression of transcripts in glucuronidation, tRNA synthetase, and immune surveillance related pathways. mtDNA levels in A549 xenografts also affected the expression of genes, such as AMACR and PHYH, involved in peroxisomal lipid metabolic pathways. Conclusion We have identified mtDNA-dependent gene expression profiles that are shared in cultured cells and in xenografts. These profiles indicate that mtDNA-depleted cells could provide informative model systems for the testing the efficacy of select classes of therapeutics, such as anti-angiogenesis agents. Furthermore, mtDNA-depleted cells grown culture and in xenografts provide a powerful means to investigate possible relationships between mitochondrial activity and gene expression profiles in normal and pathological cells.

Magda, Darren; Lecane, Philip; Prescott, Julia; Thiemann, Patricia; Ma, Xuan; Dranchak, Patricia K; Toleno, Donna M; Ramaswamy, Krishna; Siegmund, Kimberly D; Hacia, Joseph G

2008-01-01

179

VIPARnd - GeVero® tool in planning of TPS scheduled brain tumour radiotherapy  

NASA Astrophysics Data System (ADS)

In this paper, VIPARnd - GeVero® tool is presented for the first time in an application to a brain tumour radiotherapy. Whereas usefulness of VIPARnd polymer gel in various radiotherapy techniques has recently been confirmed, GeVero® software for calculation of MRI polymer gel data and comparison with TPS dose distribution simulation is now examined. The results demonstrate satisfactory agreement between polymer gel dosimetry-MRI and TPS dose distributions and prove helpfulness of the software and VIPARnd polymer gel in radiotherapy dosimetry. It is also believed that the software facilitates data processing and therefore should be of further support in po-gel dosimetry studies.

Kozicki, Marek; Maras, Piotr; Rybka, Krzysztof; Biega?ski, Tadeusz

2009-05-01

180

2.0–2.1 eV GaxIn1?xP solar cells grown on relaxed GaAsP step grades  

Microsoft Academic Search

A high quality solar cell with a bandgap in the range of 2.0-2.1 eV may enable the development of four- and five-junction solar cells for terrestrial and space applications. In this paper we describe a set of 2.0-2.1 eV nVp solar cells fabricated from Gaxln1-xP and grown on compositional step-grades of GaAs1-yPy, on GaAs substrates. Cells were grown by atmospheric

Myles A. Steiner; Ryan M. France; Mark W. Wanlass; John F. Geisz; Waldo J. Olavarria; Jeffrey J. Carapella; Anna Duda; Manuel J. Romero; Carl R. Osterwald; Paul Ciszek; Darius Kuciauskas

2010-01-01

181

"allometry" Deterministic Approaches in Cell Size, Cell Number and Crude Fiber Content Related to the Physical Quality of Kangkong (Ipomoea reptans) Grown Under Different Plant Density Pressures  

NASA Astrophysics Data System (ADS)

Kangkong, especially the upland type (Ipomoea reptans) is popularly consumed as a vegetable dish in the South East Asian countries for its quality related to Vitamins (A and C) and crude fiber contents. Higher fiber contents would prevent from the occurrence of colon cancer and diverticular disease. With young stem edible portion, its cell number and size contribute to the stem crude fiber content. The mathematical approach of allometry of cell size, number, and fiber content of stem could be used in determining the 'best' plant density pressure in producing the quality young stem to be consumed. Basically, allometry is the ratio of relative increment (growth or change) rates of two parameters, or the change rate associated to the log of measured variables relationship. Kangkog grown equal or lower than 55 plants m-2 produced bigger individual plant and good quality (physical) kangkong leafy vegetable, but with lower total yield per unit area as compared to those grown at higher densities.

Selamat, A.; Atiman, S. A.; Puteh, A.; Abdullah, N. A. P.; Mohamed, M. T. M.; Zulkeefli, A. A.; Othman, S.

182

Comprehensive Housing Market Analysis: Sebastian-Vero Beach, Floria As of April 1, 2008.  

National Technical Information Service (NTIS)

The Sebastian-Vero Beach, Florida Housing Market Area (HMA) consists of Indian River County on the Atlantic coast of Florida. The HMA is located approximately 125 miles north of Miami- Fort Lauderdale and 75 miles south of Cape Canaveral. Major industries...

2008-01-01

183

Phosgene effects on F-actin in cells grown from pulmonary tissues  

SciTech Connect

Confocal laser microscopy has been used to study the effects of phosgene on cells of the lung. Results suggest that the F-actin cytoskeleton is a molecular target and sensitive indicator of phosgene toxicity. Ovine pulmonary artery endothelial cells, exposed at 0.145 to 5.39 x LCT(50) for sheep (3300 ppm.min) showed dose response decreases in F-actin content. Doses of 0.145 and 0.265 LCT(50) caused a significant (p < .01) 25% and 42% decrease in average F-actin per cell. Dense peripheral bands (DPBs) became indistinct at > or = 1.2 LCT(50) and disappeared at > or = 2.3 LCT(50). Organization of stress fibers was parallel to the cell's long axis and was not disrupted by < 1.21 LCT(50). In secretory cells from rat tracheal explants, studies indicate a threshold of resistance to phosgene at doses < 0.2 LCT(50). However, phosgene in excess of 0.2 LCT(50) produced precipitous decreases in secretory cell F-actin. Mature, contiguous populations of untreated secretory cells contained well defined DPBs and tightly connected cell-to-cell boundaries. Exposures to 1.0 and 1.5 LCT(50) did not disrupt boundaries between secretory cells but did cause separation of boundaries between secretory and other cell types. We conclude that concentration and organization are separate aspects of phosgene's effects on F-actin and that the lesions produced are cell-type specific.

Werrlein, R.J.; Madren-Whalley, J.; Kirby, S.D.

1993-05-13

184

Surface-passivated GaAsP single-nanowire solar cells exceeding 10% efficiency grown on silicon  

NASA Astrophysics Data System (ADS)

Continued development of high-efficiency multi-junction solar cells requires growth of lattice-mismatched materials. Today, the need for lattice matching both restricts the bandgap combinations available for multi-junctions solar cells and prohibits monolithic integration of high-efficiency III-V materials with low-cost silicon solar cells. The use of III-V nanowires is the only known method for circumventing this lattice-matching constraint, and therefore it is necessary to develop growth of nanowires with bandgaps >1.4?eV. Here we present the first gold-free gallium arsenide phosphide nanowires grown on silicon by means of direct epitaxial growth. We demonstrate that their bandgap can be controlled during growth and fabricate core-shell nanowire solar cells. We further demonstrate that surface passivation is of crucial importance to reach high efficiencies, and present a record efficiency of 10.2% for a core-shell single-nanowire solar cell.

Holm, Jeppe V.; Jørgensen, Henrik I.; Krogstrup, Peter; Nygård, Jesper; Liu, Huiyun; Aagesen, Martin

2013-02-01

185

Relationship between Rejection of Several Syngeneic Tumors and Retrovirus Production by 5-Bromodeoxyuridine-grown Melanoma Cells: Lack of Protection in Natural Killer-deficient Beige Mice1  

Microsoft Academic Search

Bromodeoxyuridine-grown B16 melanoma cells (C3471) im munize mice against not only the parent melanoma but also two other C57BL\\/6 tumors: a mammary adenocarcinoma and a methylcholanthrene-induced sarcoma. We have shown that the endogenous retrovirus induced in C3471 cells by bromo- deoxyuridine can persistently infect feral mouse (SCi) cells and that they then become as efficient as C3471 cells in preventing

Selma Silagi; Theresa A. Calvelli

186

N-Linked glycans on dengue viruses grown in mammalian and insect cells  

PubMed Central

This study compared the ability of mosquito and mammalian cell-derived dengue virus (DENV) to infect human dendritic cell-specific ICAM3-grabbing non-integrin (DC-SIGN)-expressing cells and characterized the structure of envelope (E) protein N-linked glycans on DENV derived from the two cell types. DENVs derived from both cell types were equally effective at infecting DC-SIGN-expressing human monocytes and dendritic cells. The N-linked glycans on mosquito cell-derived virus were a mix of high-mannose and paucimannose glycans. In virus derived from mammalian cells, the N-linked glycans were a mix of high-mannose and complex glycans. These results indicate that N-linked glycans are incompletely processed during DENV egress from cells, resulting in high-mannose glycans on viruses derived from both cell types. Studies with full-length and truncated E protein demonstrated that incomplete processing was most likely a result of the poor accessibility of glycans on the membrane-anchored protein.

Hacker, Kari; White, Laura; de Silva, Aravinda M.

2009-01-01

187

Positioning effects on quantum dot solar cells grown by molecular beam epitaxy  

SciTech Connect

We report current-voltage and spectral response characteristics of high density InAs/GaAs quantum dot (QD) solar cells with different positions where dots are located. The short circuit current density (J{sub sc}), open circuit voltage (V{sub oc}), and external quantum efficiency of these cells under air mass 1.5 are presented and compared with a GaAs reference cell. An extended photoresponse in contrast to the GaAs reference cell was confirmed for all these cells. The effect of inserting QD layers into emitter and base region on device performance is shown. The J{sub sc} is reduced, while the V{sub oc} is maintained. The cell with QDs located toward the base side shows better performance, confirmed by both current-voltage and spectral response measurements.

Zhou, D.; Sharma, G.; Fimland, B. O. [Department of Electronics and Telecommunications, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim (Norway); Vullum, P. E.; Thomassen, S. F.; Holmestad, R.; Reenaas, T. W. [Department of Physics, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim (Norway)

2010-02-22

188

Positioning effects on quantum dot solar cells grown by molecular beam epitaxy  

NASA Astrophysics Data System (ADS)

We report current-voltage and spectral response characteristics of high density InAs/GaAs quantum dot (QD) solar cells with different positions where dots are located. The short circuit current density (Jsc), open circuit voltage (Voc), and external quantum efficiency of these cells under air mass 1.5 are presented and compared with a GaAs reference cell. An extended photoresponse in contrast to the GaAs reference cell was confirmed for all these cells. The effect of inserting QD layers into emitter and base region on device performance is shown. The Jsc is reduced, while the Voc is maintained. The cell with QDs located toward the base side shows better performance, confirmed by both current-voltage and spectral response measurements.

Zhou, D.; Vullum, P. E.; Sharma, G.; Thomassen, S. F.; Holmestad, R.; Reenaas, T. W.; Fimland, B. O.

2010-02-01

189

Thyrotropin dependent and independent thyroid cell lines selected from FRTL-5 derived tumors grown in nude mice  

SciTech Connect

FRTL-5 cells were used to set up a thyroid tumor model system in C3H nu/nu mice. FRTL-5 tumors could be grown in nude mice provided serum TSH levels were elevated. Persistent TSH elevation was obtained by administration of Na131I, rendering the mice hypothyroid. After 4 weeks FRTL-5 cells were injected sc resulting in tumor growth within 2 weeks in eight out of eight mice. Although the tumors showed an apparently undifferentiated histology, lacking normal follicular structures, they were functional since the tumors were capable of concentrating (131)iodine, as demonstrated by nuclear imaging. From one of the tumors a new cell line was isolated (FRTL-5/T) that, like the parental FRTL-5 cell line, was TSH dependent for growth. In a control group of six euthyroid nude mice FRTL-5 tumor growth could not be obtained with one exception. After 3 months one animal developed a small tumor that grew rapidly thereafter. This tumor was easily transplantable in other euthyroid nude mice, showed an undifferentiated histology, and was nonfunctional, as it could not concentrate (131)iodine. From this tumor two cell lines were derived: one cultured in the presence of TSH (FRTL-5/TP) and one in the absence of TSH (FRTL-5/TA). The cell lines were analyzed for TSH responsive functions and TSH receptor expression. Responsiveness to TSH in FRTL-5/T and the parental FRTL-5 cell line were similar for most thyroid specific functions tested. However, FRTL-5/T was less sensitive than FRTL-5 for TSH induced (3H)thymidine incorporation. Both cell lines had two classes of TSH binding sites with high and low affinity respectively. FRTL-5/TP and FRTL-5/TA were both able to grow in TSH free medium and were nonresponsive to TSH in vitro, as tested for (3H)thymidine and (3H)uridine incorporation, iodine uptake, thyroglobulin iodination, and thyroglobulin secretion.

Ossendorp, F.A.; Bruning, P.F.; Schuuring, E.M.; Van Den Brink, J.A.; van der Heide, D.; De Vijlder, J.J.; De Bruin, T.W. (Netherlands Cancer Institute, Amsterdam (Netherlands))

1990-07-01

190

Stable ciliary activity in human nasal epithelial cells grown in a perfusion system  

Microsoft Academic Search

Purpose: Explore the usefulness of a perfusion system in order to establish human nasal epithelial cell cultures suitable for long-term in vitro ciliary beat frequency (CBF) and cilio-toxicity studies. Methods: The cells were obtained by protease digestion of nasal biopsy material. The cells were plated at a density of 0.8-1 × 106\\/cm2 on Vitrogen-coated polyethylene terephthalate membranes, and cultured under

S. Dimova; V. Vlaeminck; M BREWSTER; M NOPPE; M JORISSEN; P AUGUSTIJNS

2005-01-01

191

Effect of Hypergravity on Localization Calcium Ions in Plant Cells Grown in Vivo and in Vitro  

NASA Astrophysics Data System (ADS)

Using plant callus tissues and Arabidopsis thaliana plants as model systems we have been investigated the effect of hypergravity on the localization and relative content of calcium ions in photosynthesizing cells. The tobacco callus cells in log stage of growth and mesophyll cells from developed A. thaliana leaves were used in the experiments. Plant samples were exposed to hypergravity at 6.5 g, 10g and 14 g for 15-60 min. After centrifugation, dye Fluo-4 was loaded in the control leaves and the centrifuged samples by the standard cytochemical method. Observation of calcium fluorescence was carried out with a laser confocal microscope LSM 5 Pascal at the excitation wave 488 nm (by the argon laser), at emission wavelength 516 nm. The data of the calcium ion distribution and quantification in cells were obtained using software "Pascal" (Carl Zeiss). The effect of hypergravity on redistribution of calcium ions in plant cells has been established. This effect is depended from exposure time and from the value of hypergravity. The cells cultivated in vitro is showed fast response to hypergravity influence. Plasmolysis cells and calcium domains formation have been observed in most of callus cells. This influence was like to that, which was wrote in Funaria hygrometrica protonema cells after 8.5 g influence (Sytnik et al., 1984). Leaf cells of A. thaliana were of less responsively to hypergravity than callus cells. Sytnik K, Kordyum E, Nedukha O. et al. 1984. Plant Cell Under Change of Geophysical Factors. Kiev: Naukova Dumka, 1-134 p.

Nedukha, Olena

192

Serum-Free Grown MDCK Cells: An Alternative for Influenza Vaccine Virus Production  

Microsoft Academic Search

Adaptation of MDCK cells to serum-free conditions was performed using UltraMDCK medium (BioWHITTAKER).\\u000a \\u000a Growth properties and karyotype stability of MDCK cells were monitored over a one year period of cultivation in Ultra-MDCK.\\u000a Scaling up of adapted cells to spinner culture was achieved using several porous \\/ non porous microcarriers.\\u000a \\u000a \\u000a \\u000a Adapted MDCK cells were tested for their suitability to replicate influenza

N. Kessler; G. Thomas; L. Gerentes; M. Aymard

193

Heteroepitaxial film silicon solar cell grown on Ni-W foils  

SciTech Connect

Today, silicon-wafer-based technology dominates the photovoltaic (PV) industry because it enables high efficiency, is produced from abundant, non-toxic materials and is proven in the PV marketplace.[1] However, costs associated with the wafer itself limit ultimate cost reductions.[1,2] PV based on absorber layers of crystalline Si with only 2 to 10 m thickness are a promising route to reduce these costs, while maintaining efficiencies above 15%.[3-5] With the goal of fabricating low-cost film crystalline Si (c-Si), recent research has explored wafer peeling,[6,7] crystallization of amorphous silicon films on glass,[4,8-10] and seed and epitaxy approaches.[3,5,11] In this third approach, one initially forms a seed layer that establishes the grain size and crystalline order. The Si layer is then grown heteroepitaxially on the seed layer, so that it replicates the seed crystal structure. In all of these film c-Si approaches, the critical challenge is to grow c-Si with adequate material quality: specifically, the diffusion length (LD) must be at least three times the film thickness.[12] In polycrystalline Si films, grain boundaries (GBs) are recombination-active and significantly reduce LD. This adverse effects of GBs motivates research into growth of large grained c-Si [13,14] (for a low density of GBs) and biaxially-textured c-Si [11] (for low-angle GBs).

Wee, Sung Hun [ORNL; Cantoni, Claudia [ORNL; Fanning, Thomas [Ampulse Corporation; Teplin, Charles [National Renewable Energy Laboratory (NREL); Bogorin, Daniela Florentina [ORNL; Bornstein, Jon [Ampulse Corporation; Bowers, Karen [Ampulse Corporation; Schroeter, [Ampulse Corporation; Hasoon, Falah [National Renewable Energy Laboratory (NREL); Branz, Howard [National Renewable Energy Laboratory (NREL); Paranthaman, Mariappan Parans [ORNL; Goyal, Amit [ORNL

2013-01-01

194

Antisense oligodeoxynucleotides targeting ATM strengthen apoptosis of laryngeal squamous cell carcinoma grown in nude mice  

PubMed Central

Background To conserve laryngeal function and elevate living quality of laryngeal squamous cell carcinoma (LSCC) patients, we designed antisense oligodeoxynucleotides (AS-ODNs) to reduce expression of ATM and to enhance the apoptosis of hep-2 (Human epidermoid laryngeal carcinoma) cells to radiation in vitro and in vivo. Methods The expression of ATM mRNA and protein in hep-2 cells were examined by real-time quantitative PCR and western blotting respectively. Clonogenic survival assay was carried out to detect the survival ability of hep-2 cells after irradiation, and analyzed the cell apoptosis by flow cytometry. The volume of solid tumors was measured, while TUNEL assay and western blotting used to analyze cell apoptosis and protein expression after irradiation. Results The relative ATM mRNA and protein expression in hep-2 cells treated with ATM AS-ODNs were decreased to 11.03 ± 2.51% and 48.14 ± 5.53% of that in untreated cells respectively (P <0.05). After irradiation, the survival fraction (SF) of cells treated with ATM AS-ODNs was lower than that of other groups at the same dose of radiation (P < 0.05). The inhibition rate in hep-2 cells solid tumor exposed to X-ray alone was 5.95 ± 4.52%, while it was 34.28 ± 2.43% in the group which irradiated in combination with the treatment of ATM AS-ODNs (P < 0.05). The apoptotic index for the group irradiated in combination with ATM AS-ODNs injection was 17.12 ± 4.2%, which was significantly higher than that of others (P < 0.05). Conclusion AS-ODNs of ATM reduce ATM expression and enhance hep-2 cells apoptosis to radiation in vitro and in vivo.

2011-01-01

195

MG63 Osteoblast-Like Cells Exhibit Different Behavior when Grown on Electrospun Collagen Matrix versus Electrospun Gelatin Matrix  

PubMed Central

Electrospinning is a simple and efficient method of fabricating a non-woven polymeric nanofiber matrix. However, using fluorinated alcohols as a solvent for the electrospinning of proteins often results in protein denaturation. TEM and circular dichroism analysis indicated a massive loss of triple-helical collagen from an electrospun collagen (EC) matrix, and the random coils were similar to those found in gelatin. Nevertheless, from mechanical testing we found the Young's modulus and ultimate tensile stresses of EC matrices were significantly higher than electrospun gelatin (EG) matrices because matrix stiffness can affect many cell behaviors such as cell adhesion, proliferation and differentiation. We hypothesize that the difference of matrix stiffness between EC and EG will affect intracellular signaling through the mechano-transducers Rho kinase (ROCK) and focal adhesion kinase (FAK) and subsequently regulates the osteogenic phenotype of MG63 osteoblast-like cells. From the results, we found there was no significant difference between the EC and EG matrices with respect to either cell attachment or proliferation rate. However, the gene expression levels of OPN, type I collagen, ALP, and OCN were significantly higher in MG63 osteoblast-like cells grown on the EC than in those grown on the EG. In addition, the phosphorylation levels of Y397-FAK, ERK1/2, BSP, and OPN proteins, as well as ALP activity, were also higher on the EC than on the EG. We further inhibited ROCK activation with Y27632 during differentiation to investigate its effects on matrix-mediated osteogenic differentiation. Results showed the extent of mineralization was decreased with inhibition after induction. Moreover, there is no significant difference between EC and EG. From the results of the protein levels of phosphorylated Y397-FAK, ERK1/2, BSP and OPN, ALP activity and mineral deposition, we speculate that the mechanism that influences the osteogenic differentiation of MG63 osteoblast-like cells on EC and EG is matrix stiffness and via ROCK-FAK-ERK1/2.

Tsai, Shiao-Wen; Liou, Hau-Min; Lin, Cheng-Jie; Kuo, Ko-Liang; Hung, Yi-Sheng; Weng, Ru-Chun; Hsu, Fu-Yin

2012-01-01

196

Identification of an anticancer compound against HT-29 cells from Phellinus linteus grown on germinated brown rice  

PubMed Central

Objective To isolate and identify the anticancer compound against proliferation of human colon cancer cells from ethyl acetate (EtOAC) extract of Phellinus linteus grown on germinated brown rice (PB). Methods EtOAC extract of PB was partitioned with n-hexane, EtOAC, and water-saturated n-butanol. Anticancer compound of n-hexane layer was isolated and identified by HPLC and NMR, respectively. Cytotoxicity against HT-29 cells was tested by SRB assay. Results The n-hexane layer obtained after solvent fractionation of PB EtOAC extracts showed a potent anticancer activity against the HT-29 cell line. Atractylenolide I, a eudesmane-type sesquiterpene lactone, a major anticancer substance of PB, was isolated from the n-hexane layer by silica gel column chromatography and preparative-HPLC. This structure was elucidated by one- and two-dimensional NMR spectroscopic data. Atractylenolide I has not been reported in mushrooms or rice as of yet. The isolated compound dose-dependently inhibited the growth of HT-29 human colon cancer cells. Conclusions Atractylenolide I might contribute to the anticancer effect of PB.

Jeon, Tae-Il; Jung, Chang-Hwa; Cho, Jeong-Yong; Park, Dong Ki; Moon, Jae-Hak

2013-01-01

197

Behavior of Murine Renal Carcinoma Cells Grown in Ectopic or Orthotopic Sites in Syngeneic Mice  

Microsoft Academic Search

We examined whether the organ microenvironment modulates the metastatic behavior and the response to doxorubicin (DXR) in murine renal carcinoma (RENCA) cells. Tumor cells were injected into kidney (orthotopic) and subcutis (ectopic) of syngeneic mice. Lung metastases developed in up to 57% (17\\/30) of animals having kidney tumors but not in those with skin tumors. Tumors growing in the kidney

Kwang-Sung Ahn; Yoo-Sun Jung; Jhingook Kim; Hyunah Lee; Sung-Soo Yoon

2001-01-01

198

Changes in levels of cell wall constituents in wheat seedlings grown under continuous hypergravity conditions  

NASA Astrophysics Data System (ADS)

Effects of continuous hypergravity stimuli on the amounts and composition of cell wall constituents were investigated in wheat shoots. Hypergravity (300 g) treatment for three days after germination increased the net amount of cell wall polysaccharides such as hemicellulose and cellulose, but reduced the shoot elongation. As a result, the amount of cell wall polysaccharides per unit length of shoot increased under hypergravity. The hemicellulose fraction contained polysaccharides in the middle and low molecular mass range (5 kDa-1 MDa) and increased in response to hypergravity. Also, the amounts of arabinose (Ara) and xylose (Xyl), the major sugar components of the hemicellulose fraction, increased under hypergravity conditions. In addition to wall polysaccharides, hypergravity increased the amounts of cell wall-bound phenolic acids, such as ferulic acid (FA) and diferulic acid (DFA). Furthermore, the activity of phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) was enhanced under hypergravity conditions. These results suggest that continuous hypergravity stimulates the synthesis of cell wall constituents, especially hemicellulosic arabinoxylans and cell wall-bound FA and DFA in wheat shoots. The increased PAL activity may promote the formation of FA and DFA. These changes in cell wall architecture may be involved in making rigid and tough cell walls under hypergravity conditions and thereby contribute to the ability of plant to sustain their structures against gravitational stimuli.

Wakabayashi, K.; Soga, K.; Kamisaka, S.; Hoson, T.

199

Behavior of murine renal carcinoma cells grown in ectopic or orthotopic sites in syngeneic mice.  

PubMed

We examined whether the organ microenvironment modulates the metastatic behavior and the response to doxorubicin (DXR) in murine renal carcinoma (RENCA) cells. Tumor cells were injected into kidney (orthotopic) and subcutis (ectopic) of syngeneic mice. Lung metastases developed in up to 57% (17/30) of animals having kidney tumors but not in those with skin tumors. Tumors growing in the kidney were more resistant to DXR than tumors growing in the subcutis when mice were given intravenous injections of DXR (8 mg/kg) on days 8 and 15 after implantation. In addition, tumor cells cultured from kidney tumors were initially more resistant to DXR than tumor cells cultured from subcutis tumors. After tumor cells were passaged in vitro, all cells exhibited a similar sensitivity to DXR. Additionally, we examined the expression levels of mdr1, EGFR and type IV collagenase by an in situ mRNA hybridization technique. A higher mRNA expression for type IV collagenase and EGFR was found in kidney tumors than in subcutis tumors. These results demonstrate that the organ environment influences the drug responsiveness and the expression of metastasis-related genes in murine renal carcinoma cells. PMID:11275792

Ahn, K S; Jung, Y S; Kim, J; Lee, H; Yoon, S S

200

Enhanced-depletion-width GaInNAs solar cells grown by molecular-beam epitaxy  

Microsoft Academic Search

GaInNAs, potentially useful in a 4-junction GaInP2\\/GaAs\\/GaInNAs\\/Ge solar cell, suffers from very low minority-carrier collection lengths. To date, the currents available from GaInNAs solar cells are not high enough to increase the efficiency of a 3-junction device by adding this fourth junction. Here, we grow p-i-n GaInNAs solar cells by MBE with wide, intrinsic base layers and internal QE's near

Aaron J. Ptak; Daniel J. Friedman; Sarah Kurtz; James Kiehl

2005-01-01

201

Effect of Pentagastrin on Gastric Mucosal Cells Grown in Tissue Culture.  

National Technical Information Service (NTIS)

Numerous studies have shown that chronic administration of pentagastrin leads to parietal cell hyperplasia in the rat. This indicates that gastrin may have a proliferative as well as a secretory effect on gastric mucosa. Primary explants of rat and human ...

L. R. Miller E. D. Jacobson L. R. Johnson

1972-01-01

202

In vitro studies of cells grown on the superconductor PrO(x)FeAs.  

PubMed

The recent discovery of arsenic-based high temperature superconductors has reignited interest in the study of superconductor: biological interfaces. However, the new superconductor materials involve the chemistry of arsenic and their toxicity remains unclear [Hand, E., 2008. Nature 452 (24), 922]. In this study the possible adverse effects of this new family of superconductors on cells have been examined. Cell culture studies in conjunction with microscopy and viability assays were employed to examine the influence of arsenic-based superconductor PrO(x)FeAs (x=0.75) material in vitro. Imaging data revealed that cells were well adhered and spread on the surface of the superconductor. Furthermore, cytotoxicity studies showed that cells were unaffected during the time-course of the experiments, providing support for the biocompatibility aspects of PrO(x)FeAs-based superconductor material. PMID:19179084

Yang, Shaoguang; Xie, Yuxuan; Yang, Wenrong; Zheng, Rongkun; Stevens, Frankie; Korkmaz, Emine; Weiss, Anthony S; Ringer, Simon P; Braet, Filip

2008-12-25

203

Feasibility of using thin crystalline silicon films epitaxially grown at 165 °C in solar cells: A computer simulation study  

NASA Astrophysics Data System (ADS)

We have previously reported on the successful deposition of heterojunction solar cells whose thin intrinsic crystalline absorber layer is grown using the standard radio frequency plasma enhanced chemical vapour deposition process at 165 °C on highly doped P-type (100) crystalline silicon substrates. The structure had an N-doped hydrogenated amorphous silicon emitter deposited on top of the intrinsic epitaxial silicon layer. However to form the basis of a solar cell, the epitaxial silicon film must be chiefly responsible for the photo-generated current of the structure and not the underlying crystalline silicon substrate. In this article we use detailed electrical-optical modelling to calculate the minimum thickness of the epitaxial silicon layer for this to happen. We have also investigated by modelling the influence of the a-Si:H/epitaxial-Si and epitaxial-Si/c-Si interface defects, the thickness of the epitaxial silicon layer and its volume defect density on cell performance. Finally by varying the input parameters and considering various light-trapping schemes, we show that it is possible to attain a conversion efficiency in excess of 13% using only a 5 micron thick epitaxial silicon layer.

Chakraborty, S.; Cariou, R.; Labrune, M.; Cabarrocas, P. Roca i.; Chatterjee, P.

2013-04-01

204

1H NMR Investigations of Tumor Spheroids Grown from a Human Glioma Biopsy or from a Human Malignant Glioma Cell Line  

Microsoft Academic Search

Three-dimensional spherical aggregates of cells, grown from a permanent human malignant glioma cell line (multicellular GaMG spheroids) and from a human glioma biopsy (fragment spheroids), were investigated by 1H NMR spectroscopy. In addition, 1H NMR spectra of biopsy specimens immediately after explantation and of cell monolayers from primary passage and passage 5 were acquired and compared to those of fragment

K. Kotitschke; J. C. Tonn; R. Goldbrunner; U. Bogdahn; A. Haase

1995-01-01

205

A comparative study on proliferation, macromolecular synthesis and energy metabolism of in vitro-grown ehrlich ascites tumor cells in the presence of glucosone, galactosone and methylglyoxal  

Microsoft Academic Search

Summary 1.Proliferation of in vitro grown Ehrlich ascites tumor cells is completely inhibited by 0.2–0.4 mM methylglyoxal and 1–2mM glucosone or galactosone without severely affecting viability (dye exclusion test); no phase-specific arrest of cell growth is observed.2.Incorporation of [14C] thymidine into the acid-insoluble fraction of the cells decreases within a few minutes to less than 50% of that in controls

K. A. Reiffen; F. Schneider

1984-01-01

206

Optimization towards high density quantum dots for intermediate band solar cells grown by molecular beam epitaxy  

SciTech Connect

We report high density quantum dots (QDs) formation with optimized growth temperature and V/III ratio. At lower growth temperature, QD density is increased, due to smaller surface migration length of In adatoms. With higher V/III, the QD density is higher but it results in large clusters formation and decreases the QD uniformity. The QD solar cell was fabricated and examined. An extended spectral response in contrast to the GaAs reference cell was presented but the external quantum efficiency at energies higher than GaAs band gap is reduced, resulting from the degradation for the emitter above the strained QD layers.

Zhou, D.; Sharma, G.; Fimland, B. O. [Department of Electronics and Telecommunications, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim (Norway); Thomassen, S. F.; Reenaas, T. W. [Department of Physics, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim (Norway)

2010-02-08

207

Optimization towards high density quantum dots for intermediate band solar cells grown by molecular beam epitaxy  

NASA Astrophysics Data System (ADS)

We report high density quantum dots (QDs) formation with optimized growth temperature and V/III ratio. At lower growth temperature, QD density is increased, due to smaller surface migration length of In adatoms. With higher V/III, the QD density is higher but it results in large clusters formation and decreases the QD uniformity. The QD solar cell was fabricated and examined. An extended spectral response in contrast to the GaAs reference cell was presented but the external quantum efficiency at energies higher than GaAs band gap is reduced, resulting from the degradation for the emitter above the strained QD layers.

Zhou, D.; Sharma, G.; Thomassen, S. F.; Reenaas, T. W.; Fimland, B. O.

2010-02-01

208

Clonal vaccinia virus grown in cell culture as a new smallpox vaccine  

Microsoft Academic Search

Although the smallpox virus was eradicated over 20 years ago, its potential release through bioterrorism has generated renewed interest in vaccination. To develop a modern smallpox vaccine, we have adapted vaccinia virus that was derived from the existing Dryvax vaccine for growth in a human diploid cell line. We characterized six cloned and one uncloned vaccine candidates. One clone, designated

Jian Liu; Konstantin V Pugachev; Gwendolyn A Myers; Brie Coughlin; Paul S Blum; Richard Nichols; Casey Johnson; John Cruz; Jeffrey S Kennedy; Francis A Ennis; Richard Weltzin; Thomas P Monath

2003-01-01

209

Pulmonary Microvascular Endothelial Cells Form a Tighter Monolayer When Grown in Chronic Hypoxia  

Microsoft Academic Search

Unique among the vascular beds, loss of endothelial integrity in the pulmonary microcirculation due to injury can lead to rapidly fatal hypoxemia. The ability to regain confluence and re-establish barrier function is central to restoring proper gas exchange. The adult respiratory distress syndrome (ARDS) is a heterogeneous disease, however, meaning that endothelial cells within different regions of thelungdonotlikelyseethesameoxygentensionastheyattemptto proliferate and

Victor Solodushko; James C. Parker; Brian Fouty

2007-01-01

210

Heteroepitaxial Film Silicon Solar Cell Grown on Ni-W Foils  

SciTech Connect

Heteroepitaxial semiconductor films on low-cost, flexible metal foil templates are a potential route to inexpensive, high-efficiency solar cells. Here, we report epitaxial growth of Si films on low-cost, flexible, biaxially-textured Ni-W substrates. A robust buffer architecture comprised of multiple epitaxial oxide layers has been developed to grow high quality, heteroepitaxial Si films without any undesired reaction between the Si film and the metal substrate and with a single biaxial texture. XRD analysis including {omega}-scans, {phi}-scans, and pole figures confirms that the buffers and silicon are all epitaxial, with excellent cube-on-cube epitaxy. A photo-conversion efficiency of 1.1% is demonstrated from a proof-of-concept heteroepitaxial film Si solar cell.

Wee, S. H.; Cantoni, C.; Fanning, T. R.; Teplin, C. W.; Bogorin, D. F.; Bornstein, J.; Bowers, K.; Schroeter, P.; Hasoon, F.; Branz, H. M.; Paranthaman, M. P.; Goyal, A.

2012-03-01

211

Open circuit voltage in homojunction and heterojunction silicon solar cells grown by VHF-PECVD  

Microsoft Academic Search

We present homojunction and ?c-Si\\/a-Si:H\\/c-Si heterojunction silicon solar cells fabricated by PECVD. The H2 dilution used during the i-layer growth strongly affects the device efficiency. While intermediate H2 dilution of the gas mixture results in Voc degradation, the best Voc is obtained under zero or very high (=99.4%) H2 dilution, resulting in totally amorphous or epitaxial i-layer respectively. A maximum

R. Rizzoli; E Centurioni; J Plá; C Summonte; A Migliori; A Desalvo; F Zignani

2002-01-01

212

Biological characteristics of mesenchymal stem cells grown on different topographical nanofibrous poly-L-lactide meshes.  

PubMed

The nanotopographical features of artificial scaffolds have complex effects on the biological characteristics of stem cells. They influence cell adhesion, spreading, proliferation, and differentiation; however we have limited knowledge on how these processes occur under nanotopographical cues. In this study, two kinds of electrospun nanofibrous meshes with different fiber arrangements (totally non-woven and lattice-like) were fabricated and used for in vitro culture of mesenchymal stem cells (MSCs). By comparing the characteristic marks related to osteogenic differentiation, we found that with prolonged culture time, osteopontin (OPN), osteocalcin (OCN) and alkaline phosphatase (ALP), as well as related genes (Runx2 and Colla genes), were all expressed at higher levels on lattice-like nanofibrous meshes than on non-woven ones. These results indicated that the lattice-like nanofibrous mesh activated the osteogenic differentiation of MSCs owing to changes in cell morphology directed by nanofiber orientations. Compared with pure non-woven nanofibrous meshes, lattice-like ones possessed a combined structure of parallel, magnetic-line-like, and non-woven regions. MSCs adhering onto them had upregulated expression levels of integrin subunits a5 and b1, and activated downstream signaling pathways of Ras homolog gene family member A (RhoA) and extracellular signal-regulated kinase (ERK). When the specific inhibitors PD98059 and Y27632 were used to inhibit phosphorylated ERK and p160 ROCKII activity, respectively, F-actin became disordered and the expression level of Runx2 was downregulated. Thus, we concluded that the scaffold nanotopography may modulate the microenvironment of MSCs and promote their osteogenic differentiation through the RhoA and ERK signaling pathways. These findings provided valuable information on the selection of artificial matrices suitable for MSCs application in bone tissue engineering. PMID:24015505

Zhu, Jingxian; Cai, Qing; Zhang, Xin; Hu, Xiaoqing; Li, La; Wang, Weiping; Shao, Zhenxing; Dai, Linghui; Cheng, Liyuan; Yang, Xiaoping; Zhou, Chunyan; Ao, Yingfang

2013-10-01

213

Thermal stability and inactivation of hepatitis C virus grown in cell culture  

Microsoft Academic Search

BACKGROUND: Hepatitis C virus (HCV) is a blood-borne flavivirus that infects many millions of people worldwide. Relatively little is known, however, concerning the stability of HCV and reliable procedures for inactivating this virus. METHODS: In the current study, the thermostability of cell culture-derived HCV (HCVcc, JFH-1 strain) under different environmental temperatures (37°C, room temperature, and 4°C) and the ability of

Hongshuo Song; Jin Li; Shuang Shi; Ling Yan; Hui Zhuang; Kui Li

2010-01-01

214

Area specific resistance of oxide scales grown on ferritic alloys for solid oxide fuel cell interconnects  

Microsoft Academic Search

Planar solid oxide fuel cells (SOFC) are considered to be power generators with high efficiency and low emission at small power units (1–200kWel). Many prototype systems are already successfully realized. For mass production the costs have to be reduced and the long-term stability has to be enhanced. Power losses <0.5%\\/1000h is the target value for stacks in stationary SOFC-based power

Stefan Megel; Egle Girdauskaite; Viktar Sauchuk; Mihails Kusnezoff; Alexander Michaelis

2011-01-01

215

Amorphous silicon solar cells on natively textured ZnO grown by PECVD  

Microsoft Academic Search

Natively textured ZnO layers deposited by the expanding thermal plasma CVD technique between 150 and 350°C at a deposition rate between 0.65 and 0.75 nm\\/s have been investigated with respect to their suitability as front electrode material for amorphous silicon pin solar cells in comparison to reference SnO2:F (Asahi U-type). At higher substrate temperature and with growing thickness, the surface

J. Löffler; R Groenen; J. L Linden; M. C. M van de Sanden; R. E. I Schropp

2001-01-01

216

Altered Calcium Dynamics in Cardiac Cells Grown on Silane-Modified Surfaces  

PubMed Central

Chemically defined surfaces were created using self-assembled monolayers (SAMs) of hydrophobic and hydrophilic silanes as models for implant coatings, and the morphology and physiology of cardiac myocytes plated on these surfaces were studied in vitro. We focused on changes in intracellular Ca2+ because of its essential role in regulating heart cell function. The SAM-modified coverslips were analyzed using X-ray Photoelectron Spectroscopy to verify composition. The morphology and physiology of the cardiac cells were examined using fluorescence microscopy and intracellular Ca2+ imaging. The imaging experiments used the fluorescent ratiometric dye fura-2, AM to establish both the resting Ca2+ concentration and the dynamic responses to electrical stimulation. A significant difference in excitation-induced Ca2+ changes on the different silanated surfaces was observed. However, no significant change was noted based on the morphological analysis. This result implies a difference in internal Ca2+ dynamics, and thus cardiac function, occurs when the composition of the surface is different, and this effect is independent of cellular morphology. This finding has implications for histological examination of tissues surrounding implants, the choice of materials that could be beneficial as implant coatings and understanding of cell-surface interactions in cardiac systems.

Ravenscroft-Chang, Melissa S.; Stohlman, Jayna; Molnar, Peter; Natarajan, Anupama; Canavan, Heather E.; Teliska, Maggie; Stancescu, Maria; Krauthamer, Victor; Hickman, J.J.

2013-01-01

217

Induction of IL8 expression by Cordyceps militaris grown on germinated soybeans through lipid rafts formation and signaling pathways via ERK and JNK in A549 cells  

Microsoft Academic Search

Aim of the studyIn order to elucidate immunoregulatory mechanisms of Cordyceps militaris, a methanol extract of Cordyceps militaris grown on germinated soybeans was prepared and its immunoregulatory effect in the human lung epithelial cells was investigated by examining its ability to induce IL-8 expression.

Ji Young Han; Jintaek Im; Jung Nam Choi; Choong Hwan Lee; Hye Jin Park; Dong Ki Park; Cheol-Heui Yun; Seung Hyun Han

2010-01-01

218

Proteomic analysis of Clostridium thermocellum ATCC 27405 reveals the upregulation of an alternative transhydrogenase-malate pathway and nitrogen assimilation in cells grown on cellulose.  

PubMed

Clostridium thermocellum is a Gram-positive thermophilic anaerobic bacterium with the ability to directly convert cellulosic biomass into useful products such as ethanol and hydrogen. In this study, a quantitative comparative proteomic analysis of the organism was performed to identify proteins and biochemical pathways that are differentially utilized by the organism after growth on cellobiose or cellulose. The cytoplasmic and membrane proteomes of C. thermocellum grown on cellulose or cellobiose were quantitatively compared using a metabolic (15)N isotope labelling method in conjunction with nanoLC-ESI-MS/MS (liquid chromatography - electrospray ionization - tandem mass spectrometry). In total, 1255 proteins were identified in the study, and 129 of those were able to have their relative abundance per cell compared in at least one cellular compartment in response to the substrate provided. This study reveals that cells grown on cellulose increase their abundance of phosphoenolpyruvate carboxykinase while decreasing the abundance of pyruvate dikinase and oxaloacetate decarboxylase, suggesting that the organism diverts carbon flow into a transhydrogenase-malate pathway that can increase the production of the biosynthetic intermediates NADPH and GTP. Glutamate dehydrogenase was also found to have increased abundance in cellulose-grown cells, suggesting that the assimilation of ammonia is upregulated in cells grown on the cellulosic substrates. The results illustrate a mechanism by which C. thermocellum can divert carbon into alternative pathways for the purpose of producing biosynthetic intermediates necessary to respond to growth on cellulose, including transhydrogenation of NADH to NADPH and increased nitrogen assimilation. PMID:23210995

Burton, Euan; Martin, Vincent J J

2012-11-01

219

Generation and annihilation of boron-oxygen related defects in boron-doped Czochralski-grown Si solar cells  

NASA Astrophysics Data System (ADS)

Defects that reduce the minority-carrier lifetime in silicon crystal are produced by minority-carrier injection (forward bias or light illumination) when the boron-doped Czochralski-grown silicon (Cz-Si) is used as a solar cell material. The number of induced defects is determined from changes in open-circuit voltage (VOC) of the cells. It increases with the carrier injection time, and then becomes saturated. The saturated value increases as the ambient temperature increases, during the carrier injection. These defects are observed to be vanished by thermal annealing at 200 °C for 20 min, indicating that they are in an unstable state and that some of them are annihilated even during the carrier injection. Therefore, the total number of induced defects to be determined by the difference between the generation and the annihilation rates. The activation energies for the generation process and annihilation process are evaluated to be 0.77 eV and 0.32 eV, respectively.

Vu, Tuong Khanh; Ohshita, Yoshio; Araki, Kenji; Yamaguchi, Masafumi

2002-04-01

220

Melanoma Spheroids Grown Under Neural Crest Cell Conditions Are Highly Plastic Migratory\\/Invasive Tumor Cells Endowed with Immunomodulator Function  

Microsoft Academic Search

Background: The aggressiveness of melanoma tumors is likely to rely on their well-recognized heterogeneity and plasticity. Melanoma comprises multi-subpopulations of cancer cells some of which may possess stem cell-like properties. Although useful, the sphere-formation assay to identify stem cell-like or tumor initiating cell subpopulations in melanoma has been challenged, and it is unclear if this model can predict a functional

Kiran Ramgolam; Jessica Lauriol; Claude Lalou; Laura Lauden; Laurence Michel; Abdel-Majid Khatib; Fawzi Aoudjit; Dominique Charron; Catherine Alcaide-Loridan; Reem; Pierre de la Grange

2011-01-01

221

Positron annihilation spectroscopy of AlGaAs/GaAs interfaces in metalorganic chemical vapor deposition grown GaAs heterojunction solar cells  

SciTech Connect

The defect density profile of high-efficiency epitaxial metalorganic chemical vapor deposition (MOCVD) grown GaAs heterojunction solar cell structures has been characterized using a variable-energy positron beam. Spatial defect changes, film thickness variations, and possibly interfacial space charge and disorder may be resolved from annihilation characteristics by control of the implantation depth of positrons. Correlations were made relating positron annihilation spectroscopy (PAS) measurements to surface photovoltage data, band bending, and known MOCVD growth parameter variations. Based upon these correlations, it is expected that PAS may provide a valuable means for probing defect profiles that may affect the electrical and optical response of MOCVD-grown semiconductor materials.

DeWald, A.B.; Frost, R.L.; Ringel, S.A.; Schaffer, J.P.; Rohatgi, A.; Nielsen, B.; Lynn, K.G.

1988-07-01

222

Development of a cell culture system susceptible to measles, canine distemper, and rinderpest viruses  

Microsoft Academic Search

Summary Three strains of chick embryo adapted canine distemper virus (Lederle, Wisconsin, and Onderstepoort strains) and chick embryo adapted LA strain of rinderpest virus were easily adapted to an established line of African green monkey kidney cells (Vero cells), which has been routinely employed for the titration of measles virus. By using these Vero cell adapted strains of canine distemper

A. Shishido; K. Yamanouchi; M. Hikita; T. Sato; A. Fukuda; F. Kobune

1967-01-01

223

Chloroplast RNA populations in dark-grown, light-grown, and greening Euglena gracilis.  

PubMed

RNA preparations from dark-grown, light-grown, and greening Euglena gracilis have been compared by polyacrylamide gel electrophoresis and by hybridization to Euglena chloroplast DNA. Chloroplast ribosomal RNA is not detected in dark-grown cells; its abundance increases in greening cells over a 72 hr period until the concentration characteristic of light-grown cells is reached. Other RNA species complementary to chloroplast DNA are present in comparable abundance in light-grown, dark-grown, and greening cells. PMID:5002821

Brown, R D; Haselkorn, R

1971-10-01

224

Kinetic study of phenol hydroxylase and catechol 1,2-dioxygenase biosynthesis by Candida tropicalis cells grown on different phenolic substrates  

Microsoft Academic Search

When Candida tropicalis was grown on phenol, catechol or resorcinol, the highest levels of specific activity of phenol hydroxylase (EC. 1.14.13.7) and catechol 1,2-dioxygenase (EC. 1.13.11.1) were attained with phenol. With the three aromatic compounds tested, the yeast cells exhibited sharp peaks of specific activity of both enzymes at particular incubation times. Phenol-induced cells containing high levels of both enzymes

Deifilia Ahuatzi-chacón; Guadalupe Ordorica-morales; Nora Ruiz-ordaz; Eliseo Cristiani-urbina; Cleotilde Juárez-ramírez; Juvencio Galíndez-mayer

2004-01-01

225

Nucleus image properties and cell death in MCF10F cells grown on slide substrates differing in nature and size  

Microsoft Academic Search

Summary  The immortalized human breast epithelial cell line MCF-10F is an important tool for studies on experimental tumorigenesis\\u000a induced by drugs, transfected Ha-ras oncogene, and hormones. Considering that many relevant data have thus far been established only for MCF-10F cells cultivated\\u000a on glass, and that there are data showing different cell death ratios for tumorigenic cells obtained from benzo[a]pyrene (BP)-transformed\\u000a MCF-10F

Maria Luiza S. Mello; M. H. Lareef; A. B. Santos; J. Russo; B. C. Vidal

2005-01-01

226

Clonal vaccinia virus grown in cell culture fully protects monkeys from lethal monkeypox challenge.  

PubMed

The potential use of smallpox as an agent of bioterrorism has renewed interest in the development of a modern vaccine capable of replacing the standard Dryvax vaccine. Vaccinia virus (ACAM2000), clonally isolated from Dryvax and manufactured in cell culture, was tested for immunogenicity and protective activity in a non-human primate model. Cynomolgus monkeys vaccinated with ACAM2000, Dryvax, or ACAM2000 diluent (control) were challenged 2 months post-vaccination with a lethal, intravenous dose of monkeypox virus. ACAM2000 proved immunogenic and efficacious in protecting against lethal monkeypox challenge, as evident from a lack of post-challenge viral replication, and the absence of any significant clinical signs attributable to monkeypox infection. This protection correlated (with) neutralizing antibody titers equivalent to those generated in the Dryvax group post-vaccination, as well as a similar significant increase in the presence of neutralizing antibodies post-challenge. Control animals showed no signs of vaccine-induced seroconversion, displayed post-challenge tissue-associated viral replication and viremia, and developed severe monkeypox-specific clinical symptoms. The protective efficacy of ACAM2000 was found to be equivalent to the currently approved vaccine, Dryvax. PMID:18077063

Marriott, Kathleen A; Parkinson, Christopher V; Morefield, Samantha I; Davenport, Robert; Nichols, Richard; Monath, Thomas P

2007-11-20

227

Analysis of the 5'UTR of HCV genotype 3 grown in vitro in human B cells, T cells, and macrophages  

PubMed Central

Background Previously, we have reported the isolation and molecular characterization of human Hepatitis C virus genotype 1 (HCV-1) from infected patients. We are now reporting an analysis of HCV obtained from patients infected with HCV genotype 3 (HCV-3) as diagnosed by clinical laboratories. Results HCV was cultured in vitro using our system. HCV RNA was isolated from patients' blood and from HCV cultured in various cell types for up to three months. The 5'UTR of these isolates were used for comparisons. Results revealed a number of sequence changes as compared to the serum RNA. The HCV RNA produced efficiently by infected macrophages, B-cells, and T-cells had sequences similar to HCV-1, which suggests that selection of the variants was performed at the level of macrophages. Virus with sequences similar to HCV-1 replicated better in macrophages than HCV having a 5'UTR similar to HCV-3. Conclusions Although HCV-3 replicates in cell types such as B-cells, T-cells, and macrophages, it may require a different primary cell type for the same purpose. Therefore, in our opinion, HCV-3 does not replicate efficiently in macrophages, and patients infected with HCV-3 may contain a population of HCV-1 in their blood.

2010-01-01

228

Role of proteases in the release of porcine epidemic diarrhea virus from infected cells.  

PubMed

Porcine epidemic diarrhea virus (PEDV), a causative agent of pig diarrhea, requires a protease(s) for multicycle replication in cultured cells. However, the potential role of proteases in the infection process remains unclear. In order to explore this, we used two different approaches: we infected either Vero cells in the presence of trypsin or Vero cells that constitutively express the membrane-associated protease TMPRSS2 (Vero/TMPRSS2 cells). We found that PEDV infection was enhanced, and viruses were efficiently released into the culture fluid, from Vero cells infected in the presence of protease, while in cells without protease, the virus grew, but its release into the culture fluid was strongly hampered. Cell-to-cell fusion of PEDV-infected cells and cleavage of the spike (S) protein were observed in cells with protease. When infected Vero cells were cultured for 3 days in the absence of trypsin but were then treated transiently with trypsin, infectious viruses were immediately released from infected cells. In addition, treatment of infected Vero/TMPRSS2 cells with the protease inhibitor leupeptin strongly blocked the release of virus into the culture fluid. Under electron microscopy, PEDV-infected Vero cells, as well as PEDV-infected Vero/TMPRSS2 cells treated with leupeptin, retained huge clusters of virions on their surfaces, while such clusters were rarely seen in the presence of trypsin and the absence of leupeptin in Vero and Vero/TMPRSS2 cells, respectively. Thus, the present study indicates that proteases play an important role in the release of PEDV virions clustered on cells after replication occurs. This unique observation in coronavirus infection suggests that the actions of proteases are reminiscent of that of the influenza virus neuraminidase protein. PMID:21613395

Shirato, Kazuya; Matsuyama, Shutoku; Ujike, Makoto; Taguchi, Fumihiro

2011-05-25

229

Chloroplast RNA Populations in Dark-Grown, Light-Grown, and Greening Euglena gracilis  

Microsoft Academic Search

RNA preparations from dark-grown, light-grown, and greening Euglena gracilis have been compared by polyacrylamide gel electrophoresis and by hybridization to Euglena chloroplast DNA. Chloroplast ribosomal RNA is not detected in dark-grown cells; its abundance increases in greening cells over a 72 hr period until the concentration characteristic of light-grown cells is reached. Other RNA species complementary to chloroplast DNA are

Ronald D. Brown; Robert Haselkorn

1971-01-01

230

Rhizopus oligosporus grown on natural rubber waste serum for production of single cell protein: a preliminary study  

Microsoft Academic Search

Maximum production of mycelium and utilization of total organic carbon byR. oligosporus grown on natural rubber waste serum was achieved at 28°C with an inoculum size of 7.5% (v\\/v) and grown for 144 h with an initial pH of 4.0. The maximum production of total crude protein, however, was when culture medium was inoculated with 2% (v\\/v) of spore suspension

M. S. Mahat; I. C. MacRae

1992-01-01

231

Influence of different yeast cell-wall mutants on performance and protection against pathogenic bacteria (Vibrio campbellii) in gnotobiotically-grown Artemia.  

PubMed

A selection of isogenic yeast strains (with deletion for genes involved in cell-wall synthesis) was used to evaluate their nutritional and immunostimulatory characteristics for gnotobiotically-grown Artemia. In the first set of experiments the nutritional value of isogenic yeast strains (effected in mannoproteins, glucan, chitin and cell-wall bound protein synthesis) for gnotobiotically-grown Artemia was studied. Yeast cell-wall mutants were always better feed for Artemia than the isogenic wild type mainly because they supported a higher survival but not a stronger individual growth. The difference in Artemia performance between WT and mutants feeding was reduced when stationary-phase grown cells were used. These results suggest that any mutation affecting the yeast cell-wall make-up is sufficient to improve the digestibility in Artemia. The second set of experiments, investigates the use of a small amount of yeast cells in gnotobiotic Artemia to overcome pathogenicity of Vibrio campbellii (VC). Among all yeast cell strains used in this study, only mnn9 yeast (less cell-wall bound mannoproteins and more glucan and chitin) seems to completely protect Artemia against the pathogen. Incomplete protection against the pathogen was obtained by the gas1 and chs3 mutants, which are lacking the gene for a particular cell-wall protein and chitin synthesis, respectively, resulting in more glucan. The result with the chs3 mutant is of particular interest, as its nutritional value for Artemia is comparable to the wild type. Hence, only with the chs3 strain, in contrast to the gas1 or mnn9 strains, the temporary protection to VC is not concomitant with a better growth performance under non-challenged conditions, suggesting non-interference of general nutritional effects. PMID:17240162

Soltanian, Siyavash; Dhont, Jean; Sorgeloos, Patrick; Bossier, Peter

2006-10-11

232

'Pseudomonas aeruginosa' Exotoxin: Effect on Cell Cultures.  

National Technical Information Service (NTIS)

An exotoxin, toxic to both mice and cultured cells, was isolated from cultures of Pseudomonas aeruginosa. Relatively small amounts of the exotoxin inhibited the uptake of uridine and amino acids by Vero cells. Within limits, this toxic action was reversib...

O. R. Pavlovskis F. B. Gordon

1972-01-01

233

Metabolic characteristics and lipid composition of yeastlike cells and mycelium of Mucor circinelloides var. lusitanicus INMI grown at a high glucose content in the medium  

Microsoft Academic Search

It is shown that the fungus Mucor circinelloides var. lusitanicus INMI grown under aerobic conditions in a medium with a high glucose concentration (20%) is capable of both yeastlike and\\u000a mycelial growth. In the mycelium, the activity of NAD-dependent isocitrate dehydrogenase was more than twice as high as in\\u000a yeastlike cells, whereas the isocitrate lyase activity was lower. A number

I. S. Mysyakina; N. S. Funtikova

2008-01-01

234

Effects of indoleacetic acid on the quantity of mitochondria, microbodies, and plastids in the apical and expanding cells of dark-grown oat coleoptiles  

Microsoft Academic Search

We determined the number of mitochondria, microbodies, and plastids in dark-grown oat (Avena sativa) coleoptiles following incubation in indoleacetic acid (IAA) for a period of 60 minutes at 6-minute intervals. In the apical outer epidermis of coleoptiles, the mitochondria increased from 31.4 to 35 per cell section with a 6-minute incubation in IAA, and this trend persisted over the 60-minute

J. Shen-Miller; S. R. Gawlik

1977-01-01

235

Efficient hydrogen photoproduction by synchronously grown cells of a marine cyanobacterium, Synechococcus sp. Miami BG 043511, under high cell density conditions  

SciTech Connect

The capability of hydrogen photoproduction under high cell density conditions was examined using synchronously grown cells of nitrogen-fixing Synechococcus sp. Miami BG 043511. Optimum hydrogen yield was obtained when vessels contained 0.2 to 0.3 mg chlorophyll a in 3-mL cell suspension. During a 24-h incubation period, an initial phase of hydrogen and carbon dioxide production and a subsequent phase of carbon dioxide uptake and oxygen production were observed; hence, hydrogen and oxygen accumulated as major products after 24 h. After the initial 24-h incubation, as high as 7.4 and 3.7 mL of hydrogen and oxygen, respectively, accumulated in vessels with 22-mL gas phase. This indicated that the pressure in the flask increased to 1.5 atmosphere. Energy conversion efficiency based on photosynthetically active radiation (25) (W/m[sup 2]) was about 2.6%. However, increased pressure somehow reduced the duration of hydrogen production. Duration of hydrogen and oxygen production was prolonged by periodical gas replacement during incubation.

Kumazawa, S.; Mitsui, A. (Univ. of Miami, FL (United States). School of Marine and Atmospheric Science)

1994-09-20

236

Sub-genomic RNA in Moloney leukemia virus grown in lymphoid-derived cell lines consists primarily of homologous viral RNA.  

PubMed Central

Moloney murine leukemia virus (MoMuLV) grown in 2 lymphoid-derived murine cell lines (JLS-V9 and TB) contained 2 size classes of RNA subunits: 2.8 +/- 0.4 x 10(6) (n = 30) and 1.6 +/- 0.1 x 10(6) (n = 15) daltons. Detectable levels of low molecular weight viral RNA (LMW vRNA) were not present in MoMuLV grown in mouse embryo fibroblasts, nor rat cells, nor was it produced by them when they were infected with MoMuLV containing both species of vRNA. DNA probes complementary to both subunits were synthesized separately using purified reverse transcriptase (R.T.) and calf thymus DNA as primer. Polyadenylated LMW vRNA was selected and, by molecular hybridization was found to be completely homologous with the large RNA subunit. This was confirmed using cDNA probes representing defined regions of the genome. The LMW vRNA therefore contains multiple subsets of the viral RNA, which could correspond to multiple deletion mutants possibly generated by an efficient RNA splicing mechanism. In addition, low levels of non-homologous virus-like RNA were detected in MoMuLV grown in TB (2%) AND NIH/3T3 cells (0.4%).

Ball, J K; Dekaban, G A; Loosmore, S M; Chan, S K; McCarter, J A

1979-01-01

237

CARCINOGENESIS OR TUMOURIGENICITY TESTING OF ANIMAL CELL LINES FOR VACCINE PREPARATION BY COLONY FORMATION ON SOFT AGAR AND BY AGGLUTINATION UNDER PLANT LECTINS  

Microsoft Academic Search

The carcinogenic or tumourigenic testing of seven animal kidney cell lines (F-81, CRFK, MDCK, Vero, Vero-2 cell line, MA-104 and BHK-21) established in China, were carried out in more than 700 nude mice for colony formation in soft agar and for agglutination under different density of plant lectins. Tests showed that there were correlation between cell line chromosome number variations

De-Li Zhang; Shang-Gao Liu; Long-Fei Yan; Liu-Jin Li; Gao-Sheng Huang; Fu-De Fang; Geng-Tian Xia; Xu-Yu He; Bu-Xian Gao; Xiao-Hong Bai; Wei Wang; Pei-Guo Ding

2001-01-01

238

Isolation of porcine epidemic diarrhea virus in porcine cell cultures and experimental infection of pigs of different ages  

Microsoft Academic Search

This paper describes the isolation of porcine epidemic diarrhea (PED) virus in Vero and porcine cell cultures, and the influence of age on disease in experimental infection. PED virus was isolated from the small intestine of piglets inoculated with PED samples and cultured in Vero, porcine bladder and kidney cells propagated in collagen-coated tissue culture plates in maintenance medium (MM)

Isao Shibata; Tomoyuki Tsuda; Masahumi Mori; Masaaki Ono; Masuo Sueyoshi; Katsuyoshi Uruno

2000-01-01

239

Effect of Benzyladenine, 2,4-Dichlorophenoxyacetic Acid, and d-Glucose on myo-Inositol Metabolism in Acer pseudoplatanus L. Cells Grown in Suspension Culture 1  

PubMed Central

Suspension cultures of Acer pseudoplatanus L. cells grown for 15 days in medium (T. Murashige and F. Skoog. 1962. Physiol. Plant. 15: 473-497) contained 3% sucrose, 1 mg/l 6-benzylaminopurine (BA), and 0.1 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D), referred to here as normal media, removed newly added myo-inositol-2-3H up to 100 mg/l in 24 hours and utilized up to 20% of this cyclitol for pectin biosynthesis. When the BA content of the growth medium was raised 10-fold, uptake of myo-inositol was drastically reduced and very little was available for pectin biosynthesis. Neither cell growth as measured by packed cell volume or by dry weight, nor monomer composition of pectic polysaccharides was affected by the increased level of cytokinin. Increasing, 2,4-d 10-fold instead of BA had little or no effect on myo-inositol uptake, although it did reduce the amount of myo-inositol utilized for pectin biosynthesis. Cells grown 15 days in normal media failed to remove added myo-inositol if 3% d-glucose was included. The net result was similar to that found in cells grown in the high BA condition. If a trace amount of d-galactose-1-14C was supplied to cells after 15 days of growth in normal, high BA, or high 2,4-d media, there was no significant variation in uptake and utilization of label among the three growth conditions.

Verma, Devi C.; Tavares, James; Loewus, Frank A.

1976-01-01

240

Use of cyanobacterial gas vesicles as oxygen carriers in cell culture.  

PubMed

The gas vesicles isolated from the cells of filamentous cyanobacterium Anabaena flos-aquae were treated and sterilized with glutaraldehyde and then evaluated for their effectiveness as gas carriers in cell culture. Anchorage-dependent Vero cells were grown in a packed bed of microcarrier beads under the perfusion of Dulbecco's Modified Eagle's Medium with 1% serum. The culture medium supplemented with 1.8% (v/v) gas vesicles was found to support a 30% higher maximum glucose utilization rate than the same medium without gas vesicles. The gas vesicle suspension was confirmed to have no apparent effects on cell metabolism in T-flask cultures. The study results indicated that the gas vesicles, with high oxygen carrying capacity, can be used to increase the oxygen supply in cell culture systems. PMID:19002872

Sundararajan, Anand; Ju, Lu-Kwang

2007-02-20

241

The ethyl acetate extract of Phellinus linteus grown on germinated brown rice induces G0/G1 cell cycle arrest and apoptosis in human colon carcinoma HT29 cells.  

PubMed

It is well known that Phellinus linteus has a variety of biological functions, such as antitumor and immunomodulating activities. In our previous studies, we developed a P. linteus grown on germinated brown rice (PBR) and found that organic solvent extracts of PBR possessed immunomodulating activity to regulate a balance of cytokine network in mice. The components of PBR are ergosterol peroxide, gamma-aminobutyric acid (GABA) and Beta-glucan. In this study, we demonstrate that an organic solvent extract of P. linteus grown on PBR induced apoptotic cell death through the induction of G(0)/G(1) arrest of cell cycle and the apoptosis via DNA fragmentation in human colon carcinoma HT-29 cells. Cell death induced by the extract of P. linteus grown on PBR was shown to be associated with the upregulation of p21(CIP1/WAF1), the downregulation of cyclin D1, anti-apoptotic protein, Bcl-2, the release of cytochrome c, and the activation of caspase-9, caspase-3 and caspase-8. This study suggests that the ethyl acetate extract of P. linteus grown on PBR induces apoptosis accompanied by cell cycle arrest at G(0)/G(1) phase and regulates apoptosis-regulatory proteins, which may be applicable to anticancer therapy. PMID:19998418

Park, Hye-Jin; Choi, Se Young; Hong, Se Mi; Hwang, Sung Gu; Park, Dong Ki

2010-07-01

242

Mitochondrial membrane potential measurement of H9c2 cells grown in high-glucose and galactose-containing media does not provide additional predictivity towards mitochondrial assessment.  

PubMed

Drug-induced mitochondrial toxicity is a contributing factor to many organ toxicities. The fact that some, but not all members of a particular drug class can induce mitochondrial dysfunction has necessitated the need for predictive screens within the drug development process. One of these screens is a cell viability assay done in two types of media, one containing high-glucose, the other, galactose. Since galactose-grown cells are more susceptible to mitochondrial toxicants than high-glucose-grown cells, this assay distinguishes compounds that cause toxicity primarily through mitochondrial targets from those that cause multifactorial toxicity. However, the assay does not show if compounds that cause multifactorial toxicity cause impairment on mitochondria. To address this problem, we investigated if multiplexing the assay with mitochondrial membrane potential measurements using the fluorescent dye, JC-1, could provide further information. We tested 28 drugs in the multiplexed assay and found that, although mitochondrial toxicants could be detected, no additional information was revealed about compounds that caused multifactorial toxicity. Hence, measurements with JC-1 did not provide additional information beyond what was detected using the cell viability assay. We conclude that even though the multiplexed assay is useful for HTS applications, it provides no additional value over the high-glucose-galactose cell viability assay. PMID:21126567

Rana, Payal; Nadanaciva, Sashi; Will, Yvonne

2010-11-30

243

Recombinant Wild-Type and Edmonston Strain Measles Viruses Bearing Heterologous H Proteins: Role of H Protein in Cell Fusion and Host Cell Specificity  

Microsoft Academic Search

Wild-type measles virus (MV) isolated from B95a cells has a restricted host cell specificity and hardly replicates in Vero cells, whereas the laboratory strain Edmonston (Ed) replicates in a variety of cell types including Vero cells. To investigate the role of H protein in the differential MV host cell specificity and cell fusion activity, H proteins of wild-type MV (IC-B)

Kaoru Takeuchi; Makoto Takeda; Naoko Miyajima; Fumio Kobune; Kiyoshi Tanabayashi; Masato Tashiro

2002-01-01

244

Synergistic Effect of Dual Interfacial Modifications with Room-Temperature-Grown Epitaxial ZnO and Adsorbed Indoline Dye for ZnO Nanorod Array/P3HT Hybrid Solar Cell.  

PubMed

ZnO nanorod (NR)/poly(3-hexylthiophene) (P3HT) hybrid solar cells with interfacial modifications are investigated in this work. The ZnO NR arrays are modified with room-temperature (RT)-grown epitaxial ZnO shells or/and D149 dye molecules prior to the P3HT infiltration. A synergistic effect of the dual modifications on the efficiency of the ZnO NR/P3HT solar cell is observed. The open-circuit voltage and fill factor are considerable improved through the RT-grown ZnO and D149 modifications in sequence on the ZnO NR array, which brings about a 2-fold enhancement of the efficiency of the ZnO NR/P3HT solar cell. We suggested that the more suitable surface of RT-grown ZnO for D149 adsorption, the chemical compatibility of D149 and P3HT, and the elevated conduction band edge of the RT-grown ZnO/D149-modified ZnO NR array construct the superior interfacial morphology and energetics in the RT-grown ZnO/D149-modified ZnO NR/P3HT hybrid solar cell, resulting in the synergistic effect on the cell efficiency. An efficiency of 1.16% is obtained in the RT-grown ZnO/D149-modified ZnO NR/P3HT solar cell. PMID:23937447

Chen, Dian-Wei; Wang, Ting-Chung; Liao, Wen-Pin; Wu, Jih-Jen

2013-08-26

245

Earliest art in the Americas: incised image of a proboscidean on a mineralized extinct animal bone from Vero Beach, Florida  

Microsoft Academic Search

A fragmented fossil bone incised with the figure of a proboscidean was recently found at Vero Beach, Florida near the location where Late Pleistocene fauna and human bones were recovered from 1913 to 1916. This engraving may represent the oldest and only existing example of Terminal Pleistocene art depicting a proboscidean in the Americas. Because of the uniqueness, rarity, and

Barbara A. Purdy; Kevin S. Jones; John J. Mecholsky; Gerald Bourne; Richard C. Hulbert; Bruce J. MacFadden; Krista L. Church; Michael W. Warren; Thomas F. Jorstad; Dennis J. Stanford; Melvin J. Wachowiak; Robert J. Speakman

2011-01-01

246

Power recovery of radiation damaged MOCVD grown indium phosphide on silicon solar cells through argon-ion laser annealing. Master`s thesis  

SciTech Connect

This thesis reports the results of a laser annealing technique used to remove defect sites from radiation damaged indium phosphide on silicon MOCVD grown solar cells. This involves the illumination of damaged solar cells with a continuous wave laser to produce a large forward-biased current. The InP/Si cells were irradiated with 1 MeV electrons to a given fluence, and tested for degradation. Light from an argon laser was used to illuminate four cells with an irradiance of 2.5 W/sq cm, producing a current density 3 to 5 times larger than AMO conditions. Cells were annealed at 19 deg C with the laser and at 25 deg C under AMO conditions. Annealing under laser illumination of n/p-type cells resulted in recovery of 48%. P/n type cells lost 4 to 12% of the assumed degradaton. Annealing under AMO conditions resulted in power recovery of 70% in n/p type cells. P/n-type cells recovered approximately 16% of lost power. Results indicate that significant power recovery results from the annealing of defects within n/p type InP/Si solar cells.

Boyer, L.L.

1996-06-01

247

Production of single-cell oil from prickly-pear juice fermentation by Cryptococcus curvatus grown in batch culture  

Microsoft Academic Search

The biomass of Cryptococcus curvatus, an oleaginous yeast, reached 11 g\\/l and accumulated 46% (w\\/w) lipid when grown for 35 h in batch culture on diluted (25%) prickly-pear juice. The C:N ratio of the juice was about 50 g\\/g. The efficiency of substrate conversion was 0.48 g\\/g for biomass and 0.22 g\\/g for lipids. The extracted lipids were mainly oleic

M. Hassan; P. J. Blanc; A. Pareilleux; G. Goma

1994-01-01

248

P-cracker cell temperature effects on the optical properties of AlGaInP:Be layers grown by SSMBE  

NASA Astrophysics Data System (ADS)

The optical properties of Be-doped Al0.2Ga0.3In0.5P layers grown on GaAs by solid source molecular beam epitaxy have been studied. In particular, we investigated a set of heavy doped samples grown at different phosphorous cracking temperatures (PCT). The analysis of the 15 K-PL spectra showed three strong transitions below the AlGaInP band edge associated to Be acceptor levels (A0, X), shallow impurities (A, X) and a broad signal related with oxygen deep levels (O, DL). The Photoluminescence (PL) spectra from samples dramatically change as the PCT is increased, in such a way that in the spectrum from the sample grown at the highest P-cracking zone temperature, the (O, DL) intensity is visibly dominant. Besides, we found that despite that the Be cell temperature being maintained at 1015 °C for all the samples, the Be-doping concentration is reduced as the PCT is increased. Therefore, as PCT increases, the active Be-concentration decreases as a consequence of Be-compensation with O. This phenomena is reflected in the PL properties of the samples as a reduction of the (A0, X) intensity. The rocking curves of the (0 0 4) planes obtained by high resolution X-ray diffraction (HRXRD) justify the inclusion of impurities and the reduction of the crystal quality of the sample grown at the highest PCT. This work shows that the incorporation of defects during the growth of the AlGaInP:Be films due to O contamination can be reduced using low PCT.

Soubervielle-Montalvo, C.; Hernández, I. C.; Sheldon, M.; Gorbatchev, A. Yu.; Rodríguez, A. G.; de Anda, F.; Zamora-Peredo, L.; Méndez-García, V. H.

2007-04-01

249

Activity of plasma membrane H+ATPase and expression of PMA1 and PMA2 genes in Saccharomyces cerevisiae cells grown at optimal and low pH  

Microsoft Academic Search

Cells of Saccharomyces cerevisiae grown in media with an initial pH of 2.5–6.0, acidified with a strong acid (HCl), exhibited the highest plasma membrane H+-ATPase-specific activity at an initial pH of 6.0. At a lower pH (above pH 2.5) ATPase activity (62–83% of the maximum level)\\u000a still allowed optimal growth. At pH 2.5, ATPase activity was about 30% of the

V. Carmelo; P. Bogaerts; I. Sá-Correia

1996-01-01

250

Mitochondria Increase Three-Fold and Mitochondrial Proteins and Lipid Change Dramatically in Postmeristematic Cells in Young Wheat Leaves Grown in Elevated CO2.  

PubMed Central

A dramatic stimulation in mitochondrial biogenesis during the very early stages of leaf development was observed in young wheat plants (Triticum aestivum cv Hereward) grown in elevated CO2 (650 [mu]L L-1). An almost 3-fold increase in the number of mitochondria was observed in the very young leaf cells at the base of the first leaf of a 7-d-old wheat plant. In the same cells large increases in the accumulation of a mitochondrial chaperonin protein and the mitochondrial 2-oxoglutarate dehydrogenase complex and pyruvate dehydrogenase complex were detected by immunolabeling. Furthermore, the basal segment also shows a large increase in the rate of radiolabeling of diphosphatidylglycerol, a lipid confined to the inner mitochondrial membrane. This dramatic response in very young leaf cells to elevated CO2 suggests that the numerous documented positive effects of elevated CO2 on wheat leaf development are initiated as early as 12 h postmitosis.

Robertson, E. J.; Williams, M.; Harwood, J. L.; Lindsay, J. G.; Leaver, C. J.; Leech, R. M.

1995-01-01

251

Human Lung Cancer Cells Grown in an Ex Vivo 3D Lung Model Produce Matrix Metalloproteinases Not Produced in 2D Culture  

PubMed Central

We compared the growth of human lung cancer cells in an ex vivo three-dimensional (3D) lung model and 2D culture to determine which better mimics lung cancer growth in patients. A549 cells were grown in an ex vivo 3D lung model and in 2D culture for 15 days. We measured the size and formation of tumor nodules and counted the cells after 15 days. We also stained the tissue/cells for Ki-67, and Caspase-3. We measured matrix metalloproteinase (MMP) levels in the conditioned media and in blood plasma from patients with adenocarcinoma of the lung. Organized tumor nodules with intact vascular space formed in the ex vivo 3D lung model but not in 2D culture. Proliferation and apoptosis were greater in the ex vivo 3D lung model compared to the 2D culture. After 15 days, there were significantly more cells in the 2D culture than the 3D model. MMP-1, MMP-9, and MMP-10 production were significantly greater in the ex vivo 3D lung model. There was no production of MMP-9 in the 2D culture. The patient samples contained MMP-1, MMP-2, MMP-9, and MMP-10. The human lung cancer cells grown on ex vivo 3D model form perfusable nodules that grow over time. It also produced MMPs that were not produced in 2D culture but seen in human lung cancer patients. The ex vivo 3D lung model may more closely mimic the biology of human lung cancer development than the 2D culture.

Mishra, Dhruva K.; Sakamoto, Jason H.; Thrall, Michael J.; Baird, Brandi N.; Blackmon, Shanda H.; Ferrari, Mauro; Kurie, Jonathan M.; Kim, Min P.

2012-01-01

252

Effects of three-dimensional culturing on osteosarcoma cells grown in a fibrous matrix: analyses of cell morphology, cell cycle, and apoptosis.  

PubMed

Osteosarcoma cells were cultured in stirred tank bioreactors with either a fibrous matrix or nonporous microcarriers to study the environmental effects on cell growth, morphology, cell cycle, and apoptosis. Cell cycle and apoptosis were analyzed using flow cytometry and visualized using confocal laser scanning microscopy and fluorescence microscopy. The three-dimensional (3-D) fibrous culture had better cell growth and higher metabolic rates than the two-dimensional (2-D) microcarrier culture because cells in the fibrous matrix were protected from shear stress and had lower apoptosis and cell death even under suboptimal conditions (e.g., nutrient depletion). The polyester fibrous matrix used in this study also exhibited the capability of selectively retaining viable and nonapoptotic cells and disposing apoptotic and nonviable cells. Consequently, very few apoptotic cells were found in the fibrous matrix even in the long-term (1 month) T-flask culture. In the continuous culture with packed fibrous matrixes for cell support, most cells were arrested in the G1/G0 phase after 4 days. Decreasing the dissolved oxygen level from 60 to 10% air saturation did not significantly change cell cycle and apoptosis, which remained low at approximately 15%. These results could explain why the fibrous bed bioreactor had good long-term stability and was advantageous for production of non-growth-associated proteins by animal cell cultures. PMID:14524722

Chen, Chunnuan; Chen, Kathryn; Yang, Shang-Tian

253

Significant changes in cell and chloroplast development in young wheat leaves (Triticum aestivum cv Hereward) grown in elevated CO{sub 2}  

SciTech Connect

Cell and chloroplast development were characterized in young Triticum aestivum cv Hereward leaves grown at ambient (350 {mu}L L{sup {minus}1}) or at elevated (650 {mu}L L{sup {minus}1}) CO{sub 2}. In elevated CO{sub 2}, cell and chloroplast expansion was accelerated by 10 and 25%, respectively, in the first leaf of 7-d-old wheat plants without disruption to the leaf developmental pattern. Elevated CO{sub 2} did not affect the number of chloroplasts in relation to mesophyll cell size or the linear relationship between chloroplast number or size and mesophyll cell size. No major changes in leaf anatomy or in chloroplast ultrastructure were detected as a result of growth in elevated CO{sub 2}, but there was a marked reduction in starch accumulation. In leaf sections fluorescently tagged antisera were used to visualize and quantitate the amount of cytochrome f, the {alpha}- and {beta}-subunits of the coupling factor 1 in ATP synthase, D1 protein of the photosystem II reaction center, the 33-kD protein of the extrinsic oxygen-evolving complex, subunit II of photosystem I, and ribulose-1,5-biphosphate carboxylase/oxygenase. A significant finding was that in 10 to 20% of the mesophyll cells grown in elevated CO{sub 2} the 33-kD protein of the extrinsic oxygen-evolving complex of photosystem II and cytochrome f were deficient by 75%, but the other proteins accumulated normally. 29 refs., 6 figs., 2 tabs.

Robertson, E.J.; Leech, R.M. [Univ. of York, Heslington (United Kingdom)

1995-01-01

254

Development of an IR-transparent, inverted-grown, thin-film, Al[sub 0. 34]Ga[sub 0. 66]As/GaAs cascade solar cell  

SciTech Connect

Inverted growth and the development of associated cell processing, are likely to offer a significant degree of freedom for improving the performance of many III-V multijunction cascades and open new avenues for advanced multijunction concepts. This is especially true for the development of high-efficiency Al[sub 0.37]Ga[sub 0.63]As/GaAs cascades where the high growth temperatures required for the AlGaAs top cell growth can cause the deterioration of the tunnel junction interconnect. In the approach of inverted-grown AlGaAs/GaAs cascade cells, the AlGaAs top cell is grown first at 780 [degree]C and the GaAs tunnel junction and bottom cell are grown at 675 [degree]C. After the inverted growth, the AlGaAs/GaAs cascade structure is selectively removed from the parent substrate. The feasibility of inverted growth is demonstrated by a fully-processed, inverted-grown, thin film GaAs cell with a 1-sun AM1.5 efficiency of 20.3%. Also, an inverted-grown, thin-film, Al[sub 0.34]Ga[sub 0.66]As/GaAs cascade with AM1.5 efficiencies of 19.9% and 21% at 1-sun and 7-suns, respectively, has been obtained.

Venkatasubramanian, R.; Timmons, M.L.; Sharps, P.R.; Colpitts, T.S.; Hills, J.S.; Hancock, J.; Hutchby, J.A. (Research Triangle Institute, Research Triangle Park, NC 27709 (United States))

1992-12-01

255

Autologous transplantation of ex vivo expanded bone marrow cells grown from small aliquots after high-dose chemotherapy for breast cancer.  

PubMed

The collection of small aliquots of bone marrow (BM), followed by ex vivo expansion for autologous transplantation may be less morbid, and more cost-effective, than typical BM or blood stem cell harvesting. Passive elimination of contaminating tumor cells during expansion could reduce reinoculation risks. Nineteen breast cancer patients underwent autotransplants exclusively using ex vivo expanded small aliquot BM cells (900-1200 x 10(6)). BM was expanded in media containing recombinant flt3 ligand, erythropoietin, and PIXY321, using stromal-based perfusion bioreactors for 12 days, and infused after high-dose chemotherapy. Correlations between cell dose and engraftment times were determined, and immunocytochemical tumor cell assays were performed before and after expansion. The median volume of BM expanded was 36.7 mL (range 15.8-87.0). Engraftment of neutrophils greater than 500/microL and platelets greater than 20,000/microL were 16 (13-24) and 24 (19-45) days, respectively; 1 patient had delayed platelet engraftment, even after infusion of back-up BM. Hematopoiesis is maintained at 24 months, despite posttransplant radiotherapy in 18 of the 19 patients. Transplanted CD34(+)/Lin(-) (lineage negative) cell dose correlated with neutrophil and platelet engraftment, with patients receiving greater than 2.0 x 10(5) CD34(+)/Lin(-) cells per kilogram, engrafting by day 28. Tumor cells were observed in 1 of the 19 patients before expansion, and in none of the 19 patients after expansion. It is feasible to perform autotransplants solely with BM cells grown ex vivo in perfusion bioreactors from a small aliquot. Engraftment times are similar to those of a typical 1000 to 1500 mL BM autotransplant. If verified, this procedure could reduce the risk of tumor cell reinoculation with autotransplants and may be valuable in settings in which small stem cell doses are available, eg, cord blood transplants. (Blood. 2000;95:2169-2174) PMID:10706891

Stiff, P; Chen, B; Franklin, W; Oldenberg, D; Hsi, E; Bayer, R; Shpall, E; Douville, J; Mandalam, R; Malhotra, D; Muller, T; Armstrong, R D; Smith, A

2000-03-15

256

GROWTH CHARACTERISTICS, MORPHOLOGY, AND PHOSPHOLIPID COMPOSITION OF HUMAN TYPE 2 PULMONARY ALVEOLAR CELLS GROWN IN A COLLAGEN-FREE MICROENVIRONMENT  

EPA Science Inventory

Human lung epithelial cells have been cultured and characterized for phospholipid content. Any residual fibroblasts were removed by selective trypsinization within the first 48 hours in culture. Epithelial cells were serially subpassaged when cultures reached ca. 80% confluency. ...

257

[New russian myorelaxant vero-pipecuronium (pipecuronium bromide) used for the anesthetic management of operations on the thorax and abdomen organs].  

PubMed

The experience of clinical use of the new Russian myorelaxant of the non-depolarizing action vero-pipecuronium (pipecuronium bromided) manufactured by "Veropharm" is described. Vero-pipecuronium was found to ensure splendid and good conditions for the intubation of the trachea and to maintain reliably myorelaxation. The recommended doses and availability of an antidote (prozerine) provide for a sufficiently controllable myorelaxation. Vero-pipecuronium does not virtually exert any effect on the parameters of hemodynamics and can be successfully used in patients with a high anesthetic risk including heart surgeries. Thus, Russian vero-pipecuronium has now an effective and safe myorelaxant manufactured inside the country, whose parameters are not inferior to those of pipecuronium bromide (arduan) manufactured by "Gedeon Richter", Hungary. Since the described drug is made in Russia, one can hope it will be highly effective both economically and pharmacologically. PMID:15573726

Buniatian, A A; Vyzhigina, M A; Mizikov, V M; Deshko, Iu V; Kozhevnikov, V A; Zhukova, S G; Batchaev, Sh S

258

Health assessment for Piper Aircraft Corporation, Indian River County, Vero Beach, Florida, Region 4. CERCLIS No. FLD004054284. Preliminary report  

SciTech Connect

The Piper Aircraft Corporation/Vero Beach Water and Sewer Department National Priorities List Site covers 8 acres in Vero Beach, Indiana River County, Florida. The facility began assembling and painting light aircraft in 1957. Chemicals utilized in these operations are stored on-site in underground storage tanks. In 1978, routine sampling and analysis of the city water supply revealed the presence of four volatile organic compounds: trichloroethene, 1,1-dichloroethene, cis/trans-1,2-dichloroethene and vinyl chloride. Based on available information, the site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substance via contaminated groundwater, aerated groundwater that is being discharged to the surface water, and air contaminants released from the groundwater aeration process.

Not Available

1989-04-19

259

Sensitive and rapid detection of Vero toxin-producing Escherichia coli using loop-mediated isothermal amplification  

Microsoft Academic Search

A loop-mediated isothermal amplification (LAMP) assay was developed to detect Vero toxin (VT)-producing Escherichia coli rapidly (within 60 min). The 24 strains of VT-producing E. coli were successfully amplified, but 6 strains of non-VT-producing E. coli and 46 bacterial species other than E. coli were not. The sensitivity of the LAMP assay was found to be >0.7 c.f.u. per test

Yukiko Hara-Kudo; Jiro Nemoto; Kayoko Ohtsuka; Yuko Segawa; Kosuke Takatori; Tadashi Kojima; Masanari Ikedo

2007-01-01

260

A foodborne outbreak of Vero cytotoxin-producing Escherichia coli O157:H-phage type 8 in hospital  

Microsoft Academic Search

This paper describes the epidemiological and microbiological aspects of the largest outbreak of Vero cytotoxin-producing Escherichia coli O157 (VTEC O157) infection in a hospital setting in which the route of transmission was foodborne. The outbreak, which was caused by a relatively uncommon phage type of VTEC O157, occurred in four geriatric continuing care wards in May 1997. The total number

S. J. O'Brien; P. S. Murdoch; A. H. Riley; I. King; M. Barr; S. Murdoch; A. Greig; R. Main; W. J. Reilly; F. M. Thomson-Carter

2001-01-01

261

Global gene expression profiles of canine macrophages and canine mammary cancer cells grown as a co-culture in vitro  

PubMed Central

Background Solid tumours comprise various cells, including cancer cells, resident stromal cells, migratory haemopoietic cells and other. These cells regulate tumour growth and metastasis. Macrophages constitute probably the most important element of all interactions within the tumour microenvironment. However, the molecular mechanism, that guides tumour environment, still remains unknown. Exploring the underlying molecular mechanisms that orchestrate these phenomena has been the aim of our study. A co-culture of canine mammary cancer cells and macrophages was established and maintained for 72 hrs. Having sorted the cells, gene expression in cancer cells and macrophages, using DNA microarrays, was examined. The results were confirmed using real-time qPCR and confocal microscopy. Moreover, their ability for migration and invasion has been assessed. Results Microarray analysis showed that the up-regulated genes in the cancer cell lines are involved in 15 highly over-manifested pathways. The pathways that drew our diligent attention included: the inflammation pathway mediated by chemokine and cytokine, the Toll receptor signalling pathway and the B cell activation. The up-regulated genes in the macrophages were involved in only 18 significantly over-manifested pathways: the angiogenesis, the p53 pathway feedback loops2 and the Wnt signalling pathway. The microarray analysis revealed that co-culturing of cancer cells with macrophages initiated the myeloid-specific antigen expression in cancer cells, as well as cytokine/chemokine genes expression. This finding was confirmed at mRNA and protein level. Moreover, we showed that macrophages increase cancer migration and invasion. Conclusions The presence of macrophages in the cancer environment induces acquisition of the macrophage phenotype (specific antigens and chemokines/cytokines expression) in cancer cells. We presumed that cancer cells also acquire other myeloid features, such as: capabilities of cell rolling, spreading, migration and matrix invasion (what has also been confirmed by our results). It may, perhaps, be the result of myeloid-cancer cell hybrid formation, or cancer cells mimicking macrophages phenotype, owing to various proteins secreted by macrophages.

2012-01-01

262

Growth characteristics, morphology, and phospholipid composition of human type II pulmonary alveolar cells grown in a collagen-free microenvironment  

Microsoft Academic Search

Summary  Human lung epithelial cells have been isolated and maintained in pure culture and characterized during their time in culture.\\u000a Any residual fibroblasts were removed by selective trypsinization within the first 48 h in culture and the residual epithelial\\u000a cells from the primary culture grew to confluent density. The epithelial cells at Passage 2 or greater were serially subpassaged\\u000a when cultures

George E. Milo; G. Adolph Ackerman; Ronald L. Sanders

1984-01-01

263

Effects of radiation of InP cells epitaxially grown on Si and GaAs substrates  

Microsoft Academic Search

The properties of heteroepitaxial InP cells were determined both before and after 10-MeV proton irradiations. Numerical values, obtained for the diffusion and recombination components of the reverse saturation currents, were found to be consistent with the distribution of dislocations. The radiation resistance of the heteroepitaxial cells was significantly greater than that observed for n\\/p homoepitaxial InP cells. The carrier removal

I. Weinberg; C. K. Swartz; D. J. Brinker; D. M. Wilt

1990-01-01

264

Effects of radiation of InP cells epitaxially grown on Si and GaAs substrates  

Microsoft Academic Search

The properties of heteroepitaxial InP solar cells were determined both before and after 10 MeV proton irradiations. Numerical values, obtained for the diffusion and recombination components of the reverse saturation currents, were found to be consistent with the distribution of dislocations. The radiation resistance of the heteroepitaxial cells was significantly greater than that observed for n\\/p homoepitaxial InP cells. The

I. Weinberg; C. K. Swartz; D. J. Brinker; D. M. Wilt

1990-01-01

265

Influence of sodium and potassium ions on acid production by washed cells of Streptococcus mutans ingbritt and Streptococcus sanguis NCTC 7865 grown in a chemostat.  

PubMed

A comparison was made of acid production by cells of Streptococcus mutans Ingbritt and S. sanguis NCTC 7865 that had been washed twice and incubated in different concentrations of sodium and potassium ions. Organisms were grown under defined conditions in a chemostat under both glucose limitation and glucose excess conditions at a dilution rate of 0.1 h(-1) (mean generation time, 6.9 h). Acid production after a pulse of glucose, sucrose, and fructose was measured by pH fall experiments and as a rate at pH 7.0. S. mutans produced more acid than S. sanguis as measured by either criterion, although statistically faster rates of acid production and lower terminal pH values were obtained when cells of both species were suspended in KCl rather than in NaCl, with 200 mM KCl resulting in the lowest terminal pH in pH fall experiments. Sodium ions inhibited acid production: 183 mM NaCl reduced the glycolytic rates of S. mutans and S. sanguis metabolizing glucose at pH 7.0 in 135 mM KCl by 39 and 33%, respectively. The most pronounced stimulatory effect of potassium on acid production was by washed cells of S. sanguis that had been grown under arginine and under phosphate limitation. The pH fell by a further 0.86 and 1.21 pH units, respectively, and to below the critical pH for enamel demineralization when these cells were metabolizing glucose in 135 mM KCl compared with the same concentration of NaCl. This enhancement of acid production was not due to potassium translocation, as had been suggested previously, because no movement of potassium ions across the cell membrane could be detected. An alternative explanation is proposed in which sodium ions are excluded from the cell at the expense of membrane energy, i.e., the proton motive force, which could otherwise be used for the transport of sugars. PMID:7085068

Marsh, P D; Williamson, M I; Keevil, C W; McDermid, A S; Ellwood, D C

1982-05-01

266

Photocurrent enhancement in In0.53Ga0.47As solar cells grown on InP/SiO2/Si transferred epitaxial templates  

NASA Astrophysics Data System (ADS)

InP/Si engineered substrates formed by wafer bonding and layer transfer have the potential to significantly reduce the cost and weight of III-V compound semiconductor solar cells. InP/Si substrates were prepared by He implantation of InP prior to bonding to a thermally oxidized Si substrate and annealing to exfoliate an InP thin film. Following thinning of the transferred InP film to remove surface damage caused by the implantation and exfoliation process, InGaAs solar cells lattice-matched to bulk InP were grown on these substrates using metal-organic chemical vapor deposition. The photovoltaic current-voltage characteristics of the InGaAs cells fabricated on the wafer-bonded InP/Si substrates were comparable to those synthesized on commercially available epi-ready InP substrates, and had a ~20% higher short-circuit current which we attribute to the high reflectivity of the InP/SiO2/Si bonding interface. This work provides an initial demonstration of wafer-bonded InP/Si substrates as an alternative to bulk InP substrates for solar cell applications.

Zahler, James M.; Tanabe, Katsuaki; Ladous, Corinne; Pinnington, Tom; Newman, Frederick D.; Atwater, Harry A.

2007-09-01

267

Behaviour of proplastids and their nucleoids in dark-organotrophically grown cells of Euglena gracilis transferred to an inorganic medium  

Microsoft Academic Search

Euglena gracilis Z cells in the stationary phase of dark-organotrophic growth in a culture without agitation were rich in lipid, and contained six to eight proplastids dispersed in the cytoplasm (A-type proplastids). When these cells were transferred to an inorganic medium and aerated in darkness, they showed, with the disappearance of lipid, diphasic increase in number after an induction phase,

Shinya Tsukada; Tomoko Ehara; Shuji Sumida; Tetsuaki Osafune; Eiji Hase

1986-01-01

268

PERTURBATION OF ? 1 INTEGRIN FUNCTION USING ANTISENSE OR FUNCTION-BLOCKING ANTIBODIES ON CORNEAL CELLS GROWN ON FIBRONECTIN AND TENASCIN  

Microsoft Academic Search

During corneal development, neural crest derivatives from the periocular mesenchyme migrate into the cornea and differentiate into corneal fibroblasts. During this time, these cells interact with a variety of extracellular matrices for proper orientation and development. In the present studies, we have examined the interaction of ?1 integrins on periocular mesenchyme cells (POM) and corneal fibroblasts (CF) with fibronectin and

Kathleen J. Doane; Raka Bhattacharya; Jeff Marchant

2002-01-01

269

Effects of the aspect ratio on the dye adsorption of ZnO nanorods grown by using a sonochemical method for dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

Well-aligned ZnO nanorods for the photoelectrode of dye-sensitized solar cells (DSSCs) were grown via a sonochemical method, and the effects of their aspect ratios on the dye adsorption in DSSCs were studied. The control of the aspect ratio of well-aligned ZnO nanorods was performed by tuning the mole concentration of zinc acetate dehydrate in the range of 0.04-0.06M. The dye amounts adsorbed in the ZnO nanorods were estimated from the UV-Visible absorbance by using the Beer-Lambert law. The efficiency of DSSCs with ZnO nanorods was measured to investigate the effects of the aspect ratio of the ZnO nanorods on the dye adsorption properties. A change in the aspect ratio of the ZnO nanorods was founded to yield a change in their dye adsorption ability, resulting in a change in the efficiency of the DSSCs.

Choi, Seok Cheol; Yun, Won Suk; Sohn, Sang Ho; Oh, Sang Jin

2012-11-01

270

Growth Yields and Maintenance Coefficients of Unadapted and NaCl-Adapted Tobacco Cells Grown in Semicontinuous Culture 1  

PubMed Central

Comparison of carbon utilization between unadapted and NaCl (428 millimolar) adapted tobacco (Nicotiana tabacum L.) cells under substrate limited growth conditions was facilitated using semicontinuous culture. Growth yields (Yg) and maintenance coefficients (m) of unadapted and NaCl adapted cells were similar, indicating that the efficiency of carbon utilization for growth was not altered as a result of salt adaptation and that no additional metabolic costs were associated with growth of adapted cells in the presence of a high concentration (428 millimolar) of NaCl. The Yg (0.588 grams organic dry weight gain per gram sugar uptake) and m values (0.117 grams sugar uptake per gram organic dry weight per day) were comparable in spite of substantial physiological and biochemical differences that exist between unadapted and NaCl adapted cells. Apparently, a metabolic homeostasis governs biomass production of cells before and after adaptation to salinity.

Schnapp, Sherry Rae; Curtis, Wayne R.; Bressan, Ray A.; Hasegawa, Paul M.

1991-01-01

271

Microtubules are stabilized in confluent epithelial cells but not in fibroblasts  

PubMed Central

Rhodamine-tagged tubulin was microinjected into epithelial cells (MDCK) and fibroblasts (Vero) to characterize the dynamic properties of labeled microtubules in sparse and confluent cells. Fringe pattern fluorescence photobleaching revealed two components with distinct dynamic properties. About one-third of the injected tubulin diffused rapidly in the cytoplasm with a diffusion coefficient of 1.3-1.6 x 10(- 8) cm2/s. This pool of soluble cytoplasmic tubulin was increased to greater than 80% when cells were treated with nocodazole, or reduced to approximately 20% upon treatment of cells with taxol. Fluorescence recovery of the remaining two-thirds of labeled tubulin occurred with an average half-time (t1/2) of 9-11 min. This pool corresponds to labeled tubulin associated with microtubules, since it was sensitive to treatment of cells with nocodazole and since taxol increased its average t1/2 to greater than 22 min. Movement of photobleached microtubules in the cytoplasm with rates of several micrometers per minute was shown using very small interfringe distances. A significant change in the dynamic properties of microtubules occurred when MDCK cells reached confluency. On a cell average, microtubule half-life was increased about twofold to approximately 16 min. In fact, two populations of cells were detected with respect to their microtubule turnover rates, one with a t1/2 of approximately 9 min and one with a t1/2 of greater than 25 min. Correspondingly, the rate of incorporation of microinjected tubulin into interphase microtubules was reduced about twofold in confluent MDCK cells. In contrast to the MDCK cells, no difference in microtubule dynamics was observed in sparse and confluent populations of Vero fibroblasts, where the average microtubule half- life was approximately 10 min. Thus, microtubules are significantly stabilized in epithelial but not fibroblastic cells grown to confluency.

1990-01-01

272

Stability of single and tandem junction a-Si:H solar cells grown using the ECR process  

SciTech Connect

The authors report on the fabrication and stability tests of single junction a-Si:H, and tandem junction a-Si:H/A-Si:H solar cells using the ECR process under high hydrogen dilution (H-ECR process). They show that devices with high fill factors can be made using the H-ECR process. They also report on the stability studies of the solar cells under 1 and 2-sun illumination conditions. The solar cells show very little degradation even after 500 hours of illumination under 2 x sunlight illumination.

Dalal, V.L.; Maxson, T.; Girvan, R.; Haroon, S.

1997-07-01

273

Morphological, Biological, and Biochemical Characteristics of Human Bladder Transitional Cell Carcinomas Grown in Tissue Culture and in Nude Mice1  

Microsoft Academic Search

The morphological, biological, biochemical, and karyotypic characteristics of four human bladder transitional cell carcinoma lines, SW-780, SW-800, SW-1738, and SW-1710, were investi gated. In tissue culture, each cell line presented a distinct phen- otypic expression. All but line SW-1710 grew when transplanted in the nude mouse. Light and electron microscopic studies showed morphological characteristics similar to the tumors of origin,

Aikaterini A. Kyriazis; Andreas P. Kyriazis; William B. McCombs; Ward D. Peterson

274

Growth-related glycogen levels of human intestine carcinoma cell lines grown in vitro and in vivo in nude mice.  

PubMed

The relationship known to exist in vitro between glycogen accumulation and the growth of malignant human intestine epithelial cells was investigated in vivo. The glycogen concentration of 7 human intestine carcinoma cell lines (Caco-2, HT-29, HRT-18, HCT-8R, CO-115, SW-480, and HuTu 80) was measured during cell growth for the in vitro series and during the course of tumor growth for the in vivo series. The glycogen stores were compared for these cells in vitro and after their injection in noninbred Swiss athymic nude mice. The tumors and cultured cells were ranked identically on the basis of glycogen level (Caco-2 > HRT-18 > HT-29 > HCT-8R > CO-115 > SW-480 > HuTu 80). Values for the tumors ranged from 128.8 +/- 10.8 micrograms glycogen/mg protein for Caco-2 tumors down to 2.9 +/- 0.9 micrograms for HuTu 80 tumors; similar values were found for the exponentially growing corresponding cultured cells. The tumor glycogen concentration was independent of the host's nutritional state: Glycogen concentration differed from one type of tumor to another despite its constant level in the liver; fasting did not cause tumor glycogenolysis. By the two experimental approaches, results varied during the growth phases: Stationary phase glycogen concentration increased threefold to fourfold for all cultured cell lines; tumor glycogen concentration, by contrast, was stable throughout the growth period. An inverse relationship was nonetheless found between the rate of tumor growth and tumor glycogen concentration; the highest glycogen content was associated with the slowest growing tumors, and conversely. Apparently, elevated glycogen concentration is regularly associated with decreased cell division rates in vitro and in vivo. PMID:6933258

Rousset, M; Dussaulx, E; Chevalier, G; Zweibaum, A

1980-11-01

275

Suppression of cell wall stiffening along coleoptiles of wheat ( Triticum aestivum L.) seedlings grown under osmotic stress conditions  

Microsoft Academic Search

Effects of polyethylene glycol (PEG)-induced osmotic stress on the mechanical properties of cell walls and the levels of their\\u000a components were investigated along intact wheat (Triticum aestivum L.) coleoptiles. Stress-relaxation analysis showed that the cell walls of stressed coleoptiles were loosened as compared\\u000a with those of unstressed ones not only in the apical but in the basal regions. The amounts

Kazuyuki Wakabayashi; Takayuki Hoson; Seiichiro Kamisaka

1997-01-01

276

Lactoferrin inhibits herpes simplex virus type 1 adsorption to Vero cells  

Microsoft Academic Search

This paper describes the ability of human and bovine lactoferrins (HLf; BLf), iron-binding proteins belonging to the non-immune defense system, to interfere with herpes simplex virus type 1 (HSV-1) infection. Since lactoferrins are known to bind to heparan sulphate proteoglycans and to low density lipoprotein receptor, which in turn act as binding sites for the initial interaction of HSV-1 with

Magda Marchetti; Catia Longhi; Maria Pia Conte; Silvia Pisani; Piera Valenti; Lucilla Seganti

1996-01-01

277

Inhibition of Puumala and Tula Hantaviruses in Vero Cells by MxA Protein  

Microsoft Academic Search

Human MxA protein is a type I interferon-inducible intracytoplasmic protein, which mediates antiviral actions against a variety of negative-strand RNA viruses including influenza A, measles, and vesicular stomatitis viruses. Recently, it has also been shown that several members of theBunyaviridaefamily are inhibited by MxA protein. The hantavirus genus in theBunyaviridaefamily includes important human pathogenic viruses, e.g., Puumala (PUUV), Hantaan, and

Mari Kanerva; Krister Melén; Antti Vaheri; Ilkka Julkunen

1996-01-01

278

Effects of Indoleacetic Acid on the Quantity of Mitochondria, Microbodies, and Plastids in the Apical and Expanding Cells of Dark-grown Oat Coleoptiles.  

PubMed

We determined the number of mitochondria, microbodies, and plastids in dark-grown oat (Avena sativa) coleoptiles following incubation in indoleacetic acid (IAA) for a period of 60 minutes at 6-minute intervals. In the apical outer epidermis of coleoptiles, the mitochondria increased from 31.4 to 35 per cell section with a 6-minute incubation in IAA, and this trend persisted over the 60-minute incubation. Neither the microbodies, plastids, nor the dicytosomes (Gawlik and Miller 1974 Plant Physiol 54:217-221) responded to the hormone. The apical parenchyma showed no change in quantity of any of the organelles including the dictyosomes during IAA incubation. The quick response of mitochondria in the coleoptile tip could be interpreted as an association of this organelle with hormone transport, growth, or perhaps with gravity perception. In the subapical expansion region, IAA caused significant reductions of mitochondria, microbodies, and dictyosomes in the outer epidermis compared to the control, the timing of which preceded the IAA-induced elongation and of geotropism. The fast response of organelles in the various cells is probably a change in organelle volume rather than number. That microbodies show a response to the plant hormone in the permanently achlorophyllous epidermis indicates that these organelles, in addition to their peroxisomal functions in green leaves, also may have a growth regulation function. IAA treatment was without effect on the quantity of the various types of plastids (including the amyloplasts) in the different oat coleoptile cells. PMID:16660086

Shen-Miller, J; Gawlik, S R

1977-08-01

279

Inductively coupled plasma grown semiconductor films for low cost solar cells with improved light-soaking stability  

NASA Astrophysics Data System (ADS)

We investigate the performance of a single-junction amorphous Si (a-Si) solar cell fabricated with inductively coupled plasma (ICP) deposition technique. The high-density plasma resulting from high dissociation capacity of ICP enables good-quality hydrogenated Si films to be synthesized at low temperatures. High-density ICP also promotes the diffusion of reactive radicals on substrates and forms a-Si:H films with low defect density (~3 × 1015 cm-3). We demonstrate single-junction a-Si solar cells with a conversion efficiency of 9.6% and improved light-soaking stability. This low thermal-budget thin-film technique could open up the feasibility of efficient thin film solar cells on flexible substrates.

Shen, Chang-Hong; Shieh, Jia-Min; Huang, Jung Y.; Kuo, Hao-Chung; Hsu, Chih-Wei; Dai, Bau-Tong; Lee, Ching-Ting; Pan, Ci-Ling; Yang, Fu-Liang

2011-07-01

280

Bioactive metabolite production and stress-related hormones in Devil's claw cell suspension cultures grown in bioreactors.  

PubMed

In a previous report, we showed that cell cultures of Harpagophytum procumbens, a South African plant with high medicinal value, accumulate high amounts of anti-inflammatory phenylethanoid glycosides during cultivation in shake-flasks. The aim of the present study was to transfer the phenylethanoid biosynthetic process to a 3-L stirred tank reactor and a 1-L glass-column bioreactor (operated with pulsed aeration). We found that, with stepwise increases in aeration, the stirred tank reactor yielded similar productivities of verbascoside (the major phenylethanoid glycoside in the cells) to those reported for shake-flask cultures (55.68 vs. 54.78 mg verbascoside/L/day, respectively). Transfer in the pulse-aerated column reactor resulted in 165.42 mg verbascoside/L/day, one of the highest yields reported to date. Further, to evaluate the physiological status of the suspended cells in the bioreactors cultures, we examined their hormone levels and compared them to those of cells in shake-flask cultures. While indole-3-acetic acid levels did not differ significantly between the bioreactor and shake-flask cultures, there were considerable differences in their levels of abscisic, jasmonic, and salicylic acids. These results are discussed with respect to relative stress levels in the different cultivation systems. PMID:21104241

Georgiev, Milen; Ludwig-Müller, Jutta; Weber, Jost; Stancheva, Nina; Bley, Thomas

2010-11-23

281

Discovery of Novel Human and Animal Cells Infected by the Severe Acute Respiratory Syndrome Coronavirus by Replication-Specific Multiplex Reverse Transcription-PCR  

Microsoft Academic Search

The severe acute respiratory syndrome coronavirus (SARS-CoV) is the causative agent of the recent out- break of severe acute respiratory syndrome. VeroE6 cells, fetal rhesus monkey kidney cells, and human peripheral blood mononuclear cells were the only cells known to be susceptible to SARS-CoV. We developed a multiplex reverse transcription-PCR assay to analyze the susceptibility of cells derived from a

Laura Gillim-Ross; Jill Taylor; David R. Scholl; Jared Ridenour; Paul S. Masters; David E. Wentworth

2004-01-01

282

Broad visible emission from GaN nanowires grown on n-Si (1 1 1) substrate by PVD for solar cell application  

NASA Astrophysics Data System (ADS)

Nanostructured gallium nitrides (GaNs) were grown on a catalyst-free Si (1 1 1) substrates using physical vapor deposition via thermal evaporation of GaN powder at 1150 °C in the absence of NH3 gas for different deposition time. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometer (EDX) results indicated that the growth of GaN nanostructure varies with deposition time. Both X-ray diffraction (XRD) patterns and Raman spectra reveals a hexagonal GaN with wurtzite structure. Photoluminescence (PL) showed that the UV emission was suppressed, and the visible band emission was enhanced with increasing deposition time. Enhancement of visible band emission from the GaN NWs is due to the increasement of deep level states, which was resulted from growth process. Current-voltage (IV) characteristics of GaN/Si heterostructure were measured and good rectifying behavior was observed for this photodiode (PD). The forward current under illumination was almost three times than that in the dark current at +5 V. Responsivity of the photodetector was 10.5 A/W at range from 350 nm to 500 nm, which rapidly increased to 13.6 A/W at 700 nm. We found that the fabricated photodiode PD has an infra-red (IR) photoresponse behavior. The analysis of optical and electrical properties indications that the grown GaN in the absent of NH3 is a promising optical material and has potential applications in photo voltage solar cell.

Saron, K. M. A.; Hashim, M. R.

2013-04-01

283

Biofilm-grown Mycoplasma mycoides subsp. mycoides SC exhibit both phenotypic and genotypic variation compared with planktonic cells.  

PubMed

Biofilm formation where bacterial cells adhere to a surface and surround themselves in a polysaccharide matrix is thought to be an important factor in disease initiation and persistence for many bacterial species. We have examined biofilm formation by Mycoplasma mycoides subsp. mycoides small colony using a simple model without an air/liquid interface and have found that adherent Mmm SC was more resistant to many stresses, including heat, osmotic shock and oxidative stress. Biofilms of Mmm SC also exhibited remarkable persistence and were able to survive for up to 20 weeks in stationary phase. Significant variation was seen between Mmm SC strains in their ability to form a biofilm and the morphology of the biofilm produced with some strains unable to produce microcolonies. Proteomic analysis found that a number of proteins linked to adherence were over-expressed in biofilms compared with planktonic cells. PMID:18191921

McAuliffe, Laura; Ayling, Roger D; Ellis, Richard J; Nicholas, Robin A J

2007-12-04

284

Bioactive metabolite production and stress-related hormones in Devil’s claw cell suspension cultures grown in bioreactors  

Microsoft Academic Search

In a previous report, we showed that cell cultures of Harpagophytum procumbens, a South African plant with high medicinal value, accumulate high amounts of anti-inflammatory phenylethanoid glycosides\\u000a during cultivation in shake-flasks. The aim of the present study was to transfer the phenylethanoid biosynthetic process to\\u000a a 3-L stirred tank reactor and a 1-L glass-column bioreactor (operated with pulsed aeration). We

Milen Georgiev; Jutta Ludwig-Müller; Jost Weber; Nina Stancheva; Thomas Bley

2011-01-01

285

Production of single cell protein through fermentation of a perennial grass grown on saline lands with Cellulomonas biazotea  

Microsoft Academic Search

Microbial protein from alkali-treated Leptochloa fusca (kaller grass) was produced by growing Cellulomonasbiazoteain shake flasks and in an aerated 6-l fermentor. Single cell protein, produced in the fermentor contained 56.10 ± 4.64, 60.00 ± 5.04, 11.50 ± 1.34, 12.95 ± 1.24, 3.50 ± 0.24 and 1.00 ± 0.44 true protein, crude protein, crude fibre, ash, cellulose and RNA content respectively.

M. Ibrahim Rajoka

2005-01-01

286

Aquaporin functionality in relation to H+-ATPase activity in root cells of Capsicum annuum grown under salinity.  

PubMed

As water and nutrient uptake should be related in the response of plants to salinity, the aim of this paper is to establish whether or not aquaporin functionality is related to H+-ATPase activity in root cells of pepper (Capsicum annuum L.) plants. Thus, H+-ATPase activity was measured in plasma membrane vesicles isolated from roots and aquaporin functionality was measured using a cell pressure probe in intact roots. Salinity was applied as 60 mM NaCl or 60 mM KCl, to determine which ion (Na+, K+ or Cl-) is producing the effects. We also investigated whether the effects of both salts were ameliorated by Ca2+. Similar results were obtained for cell hydraulic conductivity, Lpc, and H+-ATPase activity, large reductions in the presence at NaCl or KCl and an ameliorative effect of Ca2+. However, fusicoccin (an activator of H+-ATPase) did not alter osmotic water permeability of protoplasts isolated from roots. Addition of Hg2+ inhibited both ATPase and aquaporins, but ATPase also contains Hg-binding sites. Therefore, the results indicate that H+-ATPase and aquaporin activities may not be related in pepper plants. PMID:12654042

Martínez-Ballesta, M. Carmen; Martínez, Vicente; Carvajal, Micaela

2003-03-01

287

Antiallergic activity of novel isoflavone methyl-glycosides from Cordyceps militaris grown on germinated soybeans in antigen-stimulated mast cells.  

PubMed

Isoflavones are known to possess immunomodulating and antiallergic activities. Previously we identified novel isoflavone methyl-glycosides (daidzein 7-O-?-d-glucoside 4?-O-methylate (CDGM), glycitein 7-O-?-D-glucoside 4?-O-methylate (CGLM), genistein 7-O-?-D-glucoside 4?-O-methylate (CGNMI) and genistein 4'-O-?-D-glucoside 4?-O-methylate (CGNMII)) from Cordyceps militaris grown on germinated soybeans (GSC). The biological activity of novel isoflavone methyl-glycosides, however, remains unknown. In this study, CGNMII showed the strongest inhibition of degranulation. Additionally, the release of interleukin (IL)-4 and tumor necrosis factor (TNF)-? was decreased by CGNMII in antigen-stimulated RBL-2H3 cells. To elucidate the antiallergic mechanism of CGNMII, we examined whether it affected levels of signaling molecules responsible for degranulation. The levels of activated Lyn, Syk, PLC?1 and LAT proteins were reduced in CGNMII treated RBL-2H3 cells. CGNMII also inhibited the activation of AKT and ERK1/2 proteins. These results suggest that CGNMII might be used as a therapeutic agent for allergic diseases. PMID:22296272

Park, Dong Ki; Choi, Wahn Soo; Park, Hye-Jin

2012-02-21

288

Microbial growth on C1 compounds. Synthesis of cell constituents by methane- and methanol-grown Pseudomonas methanica  

PubMed Central

1. A study has been made of the incorporation of carbon from [14C]methane, [14C]methanol and [14C]bicarbonate by cultures of Pseudomonas methanica growing on methane, and [14C]methanol by cultures of the same organism growing on methanol. 2. The distribution of radioactivity within the non-volatile constituents of the ethanol-soluble fractions of the cells, after incubation with labelled compound for periods up to 3min., has been analysed by chromatography and radioautography. 3. Over 90% of the radioactivity fixed from [14C]methane or [14C]methanol at the earliest times of sampling appeared in phosphorylated compounds. Glucose phosphate and fructose phosphate together constituted the largest part of the radioactive phosphates (70–90%); phosphoglycerate was a relatively minor component (2–17%). Other compounds becoming labelled during the incubation included glycine, serine, glutamate, aspartate, malate, citrate and alanine. 4. The first stable products of [14C]bicarbonate fixation were malate and aspartate (containing between them over 90% of the total radioactivity fixed at the earliest times of sampling). 5. The percentage of the total radioactivity fixed that was contained in each of the radioactive compounds has been plotted against time. The slopes of the curves obtained show that hexose phosphates are primary stable products of [14C]methane and [14C]methanol incorporation and that aspartate and malate are primary stable products of [14C]bicarbonate incorporation. 6. No carboxydismutase activity has been found in cell-free extracts of the organism. This fact, together with the other findings, shows that an autotrophic metabolism involving the ribulose diphosphate cycle of carbon dioxide fixation cannot be operating.

Johnson, Patricia A.; Quayle, J. R.

1965-01-01

289

Cordyceps militaris Grown on Germinated Soybean Induces G2/M Cell Cycle Arrest through Downregulation of Cyclin B1 and Cdc25c in Human Colon Cancer HT-29 Cells  

PubMed Central

Cordyceps militaris (CM) is an insect-borne fungus that has been used in traditional Chinese medicine because of its wide range of pharmacological activities. In this paper, we studied CM grown on germinated soybean (GSC) and investigated the possible mechanisms underlying antiproliferative effect of GSC on HT-29 human colon cancer cells. In comparison with CM extracts and germinated soybean (GS) BuOH extracts, BuOH extracts of GSC showed remarkable inhibitory and antiproliferative effects on HT-29 colon cancer cells. After GSC treatment, HT-29 cells became smaller and irregular in shape. High G2/M phase cell populations were observed in the GSC-treated group. The levels of cyclin B1 and Cdc25 in the GSC-treated group were lower than those in the control group. These findings suggest that GSC BuOH extracts might act as an effective anti-proliferative agent by inducing G2/M cell cycle arrest in colon cancer cells.

Mollah, Mohammad Lalmoddin; Park, Dong Ki; Park, Hye-Jin

2012-01-01

290

Antioxidant Response to NaCl Stress in a Control and an NaCl-Tolerant Cotton Cell Line Grown in the Presence of Paraquat, Buthionine Sulfoximine, and Exogenous Glutathione.  

PubMed Central

A cotton (Gossypium hirsutum L.) control and NaCl-tolerant cell line (cv Coker 312) were grown on media with or without NaCl in the presence or absence of paraquat, buthionine sulfoximine, and oxidized glutathione. On medium with 150 mM NaCl the NaCl-tolerant cell line exhibited no reduction in growth, whereas a 96% reduction was observed in the control line. The NaCl-tolerant cell line that was grown on 150 mM NaCl exhibited significantly greater catalase (341%), peroxidase (319%), glutathione reductase (287%), ascorbate peroxidase (450%), [gamma]-glutamylcysteine synthetase (224%), and glutathione S-transferase (500%) activities than the intolerant control. The NaCl-tolerant cell line had a significantly lower dehydroascorbic acid/ascorbic acid ratio. Paraquat reduced growth by 20 and 53.7%, respectively, in the NaCl-tolerant and control cell line. The NaCl-tolerant cell line also showed a slight tolerance to buthionine sulfoximine. In the buthionine sulfoximine experiments reduced glutathione restored growth in both cell lines, whereas oxidized glutathione restored growth only in the NaCl-tolerant cell line. These data indicate that the NaCl-tolerant cell line exhibited a cross-tolerance to a variety of stress variables and had a more active ascorbate-glutathione cycle.

Gossett, D. R.; Banks, S. W.; Millhollon, E. P.; Lucas, M. C.

1996-01-01

291

Predictive uncertainty in infrared marker-based dynamic tumor tracking with Vero4DRT.  

PubMed

Purpose: To quantify the predictive uncertainty in infrared (IR)-marker-based dynamic tumor tracking irradiation (IR Tracking) with Vero4DRT (MHI-TM2000) for lung cancer using logfiles.Methods: A total of 110 logfiles for 10 patients with lung cancer who underwent IR Tracking were analyzed. Before beam delivery, external IR markers and implanted gold markers were monitored for 40 s with the IR camera every 16.7 ms and with an orthogonal kV x-ray imaging subsystem every 80 or 160 ms. A predictive model [four-dimensional (4D) model] was then created to correlate the positions of the IR markers (PIR) with the three-dimensional (3D) positions of the tumor indicated by the implanted gold markers (Pdetect). The sequence of these processes was defined as 4D modeling. During beam delivery, the 4D model predicted the future 3D target positions (Ppredict) from the PIR in real-time, and the gimbaled x-ray head then tracked the target continuously. In clinical practice, the authors updated the 4D model at least once during each treatment session to improve its predictive accuracy. This study evaluated the predictive errors in 4D modeling (E4DM) and those resulting from the baseline drift of PIR and Pdetect during a treatment session (EBD). E4DM was defined as the difference between Ppredict and Pdetect in 4D modeling, and EBD was defined as the mean difference between Ppredict calculated from PIR in updated 4D modeling using (a) a 4D model created from training data before the model update and (b) an updated 4D model created from new training data.Results: The mean E4DM was 0.0 mm with the exception of one logfile. Standard deviations of E4DM ranged from 0.1 to 1.0, 0.1 to 1.6, and 0.2 to 1.3 mm in the left-right (LR), anterior-posterior (AP), and superior-inferior (SI) directions, respectively. The median elapsed time before updating the 4D model was 13 (range, 2-33) min, and the median frequency of 4D modeling was twice (range, 2-3 times) per treatment session. EBD ranged from -1.0 to 1.0, -2.1 to 3.3, and -2.0 to 3.5 mm in the LR, AP, and SI directions, respectively. EBD was highly correlated with BDdetect in the LR (R = -0.83) and AP directions (R = -0.88), but not in the SI direction (R = -0.40). Meanwhile, EBD was highly correlated with BDIR in the SI direction (R = -0.67), but not in the LR (R = 0.15) or AP (R = -0.11) direction. If the 4D model was not updated in the presence of intrafractional baseline drift, the predicted target position deviated from the detected target position systematically.Conclusions: Application of IR Tracking substantially reduced the geometric error caused by respiratory motion; however, an intrafractional error due to baseline drift of >3 mm was occasionally observed. To compensate for EBD, the authors recommend checking the target and IR marker positions constantly and updating the 4D model several times during a treatment session. PMID:24007138

Akimoto, Mami; Nakamura, Mitsuhiro; Mukumoto, Nobutaka; Tanabe, Hiroaki; Yamada, Masahiro; Matsuo, Yukinori; Monzen, Hajime; Mizowaki, Takashi; Kokubo, Masaki; Hiraoka, Masahiro

2013-09-01

292

Comparison of initial feasibility of host cell lines for viral vaccine production.  

PubMed

In order to reduce the time required for the development and production of viral vaccines, host cell lines should be available as expression systems for production of viral vaccines against groups of viral pathogens. A selection of cell lines was compared for their initial feasibility as expression system for the replication of polioviruses, influenza A viruses and respiratory syncytial virus (wild type strain A2). Six adherent cell lines (Vero, HEK-293, MRC-5, CHO-K1, BHK-21 c13, MDCK) and six single cell suspension cell lines (CAP, AGE1.CR.HS, sCHO-K1, BHK-21 c13 2p, MDCK SFS) were studied for their ability to propagate viruses. First, maximum cell densities were determined. Second, virus receptor expression and polarization of the cell lines regarding receptor distribution of eight different viruses were monitored using flow cytometry and immunocytochemistry. Organization of the actin cytoskeleton was studied by transfection of the cells with Lifeact™, a construct coding for actin-EGFP. Finally, the ability to produce virus progeny of the viruses studied was assayed for each cell line. The results suggest that single cell suspension cell lines grown on serum free medium are the best candidates to serve as host cell lines for virus replication. PMID:23684847

Vlecken, Danielle H W; Pelgrim, Ralf P M; Ruminski, Slawomir; Bakker, Wilfried A M; van der Pol, Leo A

2013-05-14

293

A rapid method for the differentiation of yeast cells grown under carbon and nitrogen-limited conditions by means of partial least squares discriminant analysis employing infrared micro-spectroscopic data of entire yeast cells  

PubMed Central

This paper shows the ease of application and usefulness of mid-IR measurements for the investigation of orthogonal cell states on the example of the analysis of Pichia pastoris cells. A rapid method for the discrimination of entire yeast cells grown under carbon and nitrogen-limited conditions based on the direct acquisition of mid-IR spectra and partial least squares discriminant analysis (PLS-DA) is described. The obtained PLS-DA model was extensively validated employing two different validation strategies: (i) statistical validation employing a method based on permutation testing and (ii) external validation splitting the available data into two independent sub-sets. The Variable Importance in Projection scores of the PLS-DA model provided deeper insight into the differences between the two investigated states. Hence, we demonstrate the feasibility of a method which uses IR spectra from intact cells that may be employed in a second step as an in-line tool in process development and process control along Quality by Design principles.

Kuligowski, Julia; Quintas, Guillermo; Herwig, Christoph; Lendl, Bernhard

2012-01-01

294

Impact of trichloroethylene contaminated groundwater discharged to the main canal and Indian River lagoon, Vero Beach, Florida  

SciTech Connect

Groundwater highly contaminated with trichloroethylene (TCE) from a leaky storage tank was detected in Vero Beach, Florida in 1978. Aware of this problem, the local and state authorities gave permission to pump out the contaminated water as a means of reducing concentrations in the aquifer. The water was air sprayed to strip the organic compounds and subsequently discharged and mixed by means of a hydraulic pump in the drainage canal. The average discharge rate of contaminated water into the canal was approximately 0.2 million gallons per day. This project was initiated to determine the spatial distribution of pollutants in the canal and river as well as rainfall and canal flow rate effects on water, sediment, and biological organisms. Prior to flushing the well, a baseline survey of trichloroethylene and other related compounds in the canal and river was performed.

Wang, T.; Lenahan, R.; Kanik, M.

1985-04-01

295

Growth and characterization of Czochralski-grown n and p-type GaAs for space solar cell substrates. Final Report, 29 May 1981-28 May 1982  

SciTech Connect

Progress in LEC (liquid encapsulated Czochralski) crystal growth techniques for producing high-quality, 3-inch-diameter, n- and p-type GaAs crystals suitable for solar cell applications is described. The LEC crystals with low dislocation densities and background impurities, high electrical mobilities, good dopant uniformity, and long diffusion lengths were reproducibly grown through control of the material synthesis, growth and doping conditions. The capability for producing these large-area, high-quality substrates should positively impact the manufacturability of highly efficiency, low cost, radiation-hard GaAs solar cells.

Chen, R.T.

1983-06-01

296

Estrogen induction of progestophilins in rat estrogen-sensitive cells grown in media supplemented with sera from castrated rats and from rats bearing an alpha-fetoprotein-secreting hepatoma.  

PubMed

The purpose of this work was to study the effect of alpha-fetoprotein (AFP) over cell multiplication and the induction of an estradiol-17 beta (E2)-dependent marker, i.e., progestophilins in E-sensitive cells C2(9)RAP derived from a W/Fu rat pituitary tumor. These cells proliferate in isogeneic hosts under the influence of E2, while they proliferate in culture regardless of the presence of E2. C2(9)RAP cells were grown in medium supplemented with 10% horse serum. Progestophilin levels were measured 48 h after adding serum (20% horse, or castrated rat, or AFP-secreting tumor-bearing rat) and estrogen to the 10% horse serum-supplemented medium in which the cells were growing. Maximal induction of progestophilins was obtained at 3 X 10(-10) M E2 in cells grown in medium containing horse or castrated rat serum. In contrast, maximal induction of progestophilins required 3 X 10(-8) M E2 in cells grown in medium supplemented with the serum of Morris hepatoma 7777-bearing rats. This serum contained AFP levels comparable to those present at birth in the rat. 11-Methoxy-17 beta ethynylestradiol (R2858), a synthetic estrogen with little affinity for AFP, was also tested for its ability to induce progestophilins. The degree of maximal induction of progestophilins expressed as percentage of the respective control, was similar for all experimental groups, both with E2 and with R2858. In addition, we compared the free E2 levels in the culture medium with the progestophilin levels and the cell proliferation rate. We found that the progestophilin levels were maximal at free E2 concentrations above 11 pg E2/ml, whereas there was no correlation between the free E2 levels and the proliferation rate. Moreover, the proliferation rate of cells in medium supplemented with horse or castrated rat serum was maximal at concentrations of free E2 below 0.4 pg/ml; whereas cell proliferation was inhibited with hepatoma serum even at concentrations of free E2 of 44 pg/ml. We conclude that the effect of hepatoma serum on the E2 induction of progestophilins seems to be mediated by the effect of AFP on the availability of free estrogen, since it is abolished by the addition of both natural and synthetic estrogens. The inhibitory effect of hepatoma serum upon cell proliferation is not reversed by estrogens and thus seems to be mediated by mechanisms other than E2 trapping by AFP. PMID:6198194

Soto, A M; Lee, H; Siiteri, P K; Murai, J T; Sonnenschein, C

1984-02-01

297

Adaptation of the Lapinized Rinderpest Virus to in vitro Growth and Attenuation of Its Virulence in Rabbits  

Microsoft Academic Search

SUMMARY A lapinized rinderpest virus, the L strain, which is virulent in rabbits and had been grown only in rabbits, was adapted to grow in Vero cells by the fusion of Vero cells with virus-infected rabbit spleen cells in the presence of polyethylene glycol, and subsequently passaged in Veto cells by co-culture technique. After several passages, free virus was produced

HIROSHI ISHII; YASUHIRO YOSHIKAWA; KAZUYA YAMANOUCHI

1986-01-01

298

Graphic Grown Up  

ERIC Educational Resources Information Center

It's no secret that children and YAs are clued in to graphic novels (GNs) and that comics-loving adults are positively giddy that this format is getting the recognition it deserves. Still, there is a whole swath of library card-carrying grown-up readers out there with no idea where to start. Splashy movies such as "300" and "Spider-Man" and their…

Kim, Ann

2009-01-01

299

Graphic Grown Up  

ERIC Educational Resources Information Center

|It's no secret that children and YAs are clued in to graphic novels (GNs) and that comics-loving adults are positively giddy that this format is getting the recognition it deserves. Still, there is a whole swath of library card-carrying grown-up readers out there with no idea where to start. Splashy movies such as "300" and "Spider-Man" and their…

Kim, Ann

2009-01-01

300

Improved photoresponsivity of semiconducting BaSi2 epitaxial films grown on a tunnel junction for thin-film solar cells  

NASA Astrophysics Data System (ADS)

The highest photoresponsivity and an internal quantum efficiency exceeding 70% at 1.55 eV were achieved for 400 nm thick undoped n-type BaSi2 epitaxial layers formed on a n+-BaSi2/p+-Si tunnel junction (TJ) on Si(111). The diffusion of Sb atoms was effectively suppressed by an intermediate polycrystalline Si layer grown by solid phase epitaxy, located between the TJ and undoped BaSi2 layers.

Du, Weijie; Suzuno, Mitsushi; Ajmal Khan, M.; Toh, Katsuaki; Baba, Masakazu; Nakamura, Kotaro; Toko, Kaoru; Usami, Noritaka; Suemasu, Takashi

2012-04-01

301

Synthesis and characterization of platinum nanoparticles on in situ grown carbon nanotubes based carbon paper for proton exchange membrane fuel cell cathode  

Microsoft Academic Search

Multi-walled carbon nanotubes (MWCNTs) based micro-porous layer on the carbon paper substrates was prepared by in situ growth in a chemical vapor deposition setup. Platinum nanoparticles were deposited on in situ grown MWCNTs\\/carbon paper by a wet chemistry route at <100°C. The in situ MWCNTs\\/carbon paper was initially surface modified by silane derivative to incorporate sulfonic acid–silicate intermediate groups which

V. Kamavaram; V. Veedu; A. M. Kannan

2009-01-01

302

Poliovirus Vaccine Inactivated (Monkey Kidney Cell) (IPOL)  

Center for Biologics Evaluation and Research (CBER)

Text Version... as the current vaccine except the cell 'substrate was ... the vaccine l!Iade in Vero cells were carried ... Hopkins study by a follow-up telephone' call with ... More results from www.fda.gov/downloads/biologicsbloodvaccines/vaccines

303

Improved photoresponsivity of semiconducting BaSi{sub 2} epitaxial films grown on a tunnel junction for thin-film solar cells  

SciTech Connect

The highest photoresponsivity and an internal quantum efficiency exceeding 70% at 1.55 eV were achieved for 400 nm thick undoped n-type BaSi{sub 2} epitaxial layers formed on a n{sup +}-BaSi{sub 2}/p{sup +}-Si tunnel junction (TJ) on Si(111). The diffusion of Sb atoms was effectively suppressed by an intermediate polycrystalline Si layer grown by solid phase epitaxy, located between the TJ and undoped BaSi{sub 2} layers.

Du, Weijie; Suzuno, Mitsushi; Ajmal Khan, M.; Toh, Katsuaki; Baba, Masakazu; Nakamura, Kotaro; Toko, Kaoru [Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennohdai, Tsukuba, Ibaraki 305-8573 (Japan); Usami, Noritaka [Institute for Materials Research, Tohoku University, Sendai, Miyagi 980-8577 (Japan); Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075 (Japan); Suemasu, Takashi [Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennohdai, Tsukuba, Ibaraki 305-8573 (Japan); Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075 (Japan)

2012-04-09

304

Adaptation of Puumala Hantavirus to Cell Culture Is Associated with Point Mutations in the Coding Region of the L Segment and in the Noncoding Regions of the S Segment  

Microsoft Academic Search

We previously developed a model for studies on hantavirus host adaptation and initiated genetic analysis of Puumala virus variants passaged in colonized bank voles and in cultured Vero E6 cells. With the data presented in this paper, the sequence comparison of the wild-type and Vero E6-adapted variants of Puumala virus, strain Kazan, has been completed. The only amino acid substitution

Kirill Nemirov; A. Lundkvist; A. Vaheri; A. Plyusnin

2003-01-01

305

Free amino acid and phenolic contents and antioxidative and cancer cell-inhibiting activities of extracts of 11 greenhouse-grown tomato varieties and 13 tomato-based foods.  

PubMed

Tomato (Solanum lycopersicum) plants synthesize nutrients, pigments, and bioactive compounds that benefit nutrition and human health. The nature and concentrations of these compounds are strongly influenced by varietal factors such as size and color as well as by processing. To better understand how these factors affect the concentration of nutrients and bioactive compounds, we analyzed 11 Korean tomato varieties grown under the same greenhouse conditions and 13 processed commercial tomato products for free amino acids and amino acid metabolites by HPLC, for individual phenolics by HPLC-MS, for total phenolics by the Folin-Ciocalteu method, for antioxidative activity by the FRAP and DPPH methods, and for cancer cell-inhibiting effects by the MTT assay. We also determined the protein content of the tomatoes by an automated Kjeldahl method. The results show that there is a broad range of bioactive compounds across tomato varieties and products. Small tomatoes had higher contents of bioactive compounds than the large ones. The content of phenolic compounds of processed products was lower than that of fresh tomatoes. Tomato extracts promoted growth in normal liver (Chang) cells, had little effect in normal lung (Hel299) cells, mildly inhibited growth of lung cancer (A549) cells, and first promoted and then, at higher concentrations, inhibited growth in lymphoma (U937) cells. The relationship of cell growth to measured constituents was not apparent. Dietary and health aspects of the results are discussed. PMID:22070764

Choi, Suk-Hyun; Kim, Hyen-Ryung; Kim, Hyun-Jeong; Lee, In-Seon; Kozukue, Nobuyuki; Levin, Carol E; Friedman, Mendel

2011-11-17

306

Compartmentation of metals in foliage of Populus tremula grown on soils with mixed contamination. II. Zinc binding inside leaf cell organelles.  

PubMed

The phytoextraction potential of plants for removing heavy metals from polluted soils is determined by their capacity to store contaminants in aboveground organs and complex them safely. In this study, the metal compartmentation, elemental composition of zinc deposits and zinc complexation within leaves from poplars grown on soil with mixed metal contamination was analysed combining several histochemical and microanalytical approaches. Zinc was the only heavy metal detected and was stored in several organelles in the form of globoid deposits showing ?-metachromasy. It was associated to oxygen anions and different cations, noteworthy phosphorous. The deposit structure, elemental composition and element ratios indicated that zinc was chelated by phytic acid ligands. Maturation processes in vacuolar vs. cytoplasmic deposits were suggested by differences in size and amounts of complexed zinc. Hence, zinc complexation by phytate contributed to metal detoxification and accumulation in foliage but could not prevent toxicity reactions therein. PMID:20427108

Vollenweider, Pierre; Bernasconi, Petra; Gautschi, Hans-Peter; Menard, Terry; Frey, Beat; Günthardt-Goerg, Madeleine S

2010-04-28

307

Antiviral activity of Aloe vera against herpes simplex virus type 2: An in vitro study  

Microsoft Academic Search

In this study we tested the antiviral activity of a crude hot glycerine extract of Aloe vera gel which was grown in Bushehr (Southwest of Iran) against HSV-2 replication in Vero cell line. The extract showed antiviral activity against HSV-2 not only before attachment and entry of virus to the Vero cells but also on post attachment stages of virus

Moloud Abbas; Persian Gulf

308

Ability of inhibitors of glycosylation and protein synthesis to sensitize cells to abrin, ricin, Shigella toxin, and Pseudomonas toxin.  

PubMed

A number of compounds that interfere with glycoprotein synthesis and transport have been tested for their ability to sensitize cells to cancerostatic protein toxins. Tunicamycin, swainsonine, cycloheximide, and puromycin sensitized Vero cells and HeLa cells to abrin and ricin, as we have found previously with monensin (K. Sandvig and S. Olsnes, J. Biol. Chem., 257: 7504-7513, 1982). Cycloheximide, but not swainsonine, sensitized Vero cells to Pseudomonas exotoxin A and Shigella toxin. The ability of ricin to intoxicate cells was much lower at 19 degrees C than at 37 degrees C and there was almost no sensitizing effect of cycloheximide and monensin at 19 degrees C. Studies by electron microscopy showed that ricin conjugated to horseradish peroxidase appeared in trans Golgi elements in Vero cells. Possibly, transport of ricin into the cytosol requires passage through the Golgi apparatus. The possibility that the sensitizing agents here described may be valuable in enhancing the action of immunotoxins is discussed. PMID:3096563

Sandvig, K; Tønnessen, T I; Olsnes, S

1986-12-01

309

Hydrothermally grown upright-standing nanoporous nanosheets of iodine-doped ZnO (ZnO:I) nanocrystallites for a high-efficiency dye-sensitized solar cell.  

PubMed

Upright-standing nanoporous nanosheets of iodine-doped ZnO (ZnO:I) nanocrsytallites were grown hydrothermally at low temperature and studied as dye-sensitized solar-cell electrodes. The highest overall energy-conversion efficiency of ~6.6% was achieved with the film consisted of nanosheets of ZnO:I nanocrystallites. This efficiency was significantly improved than the 3.2% achieved for ZnO:I films only including nanosized crystallites, and higher than the 2.4% for undoped ZnO nanosheet film. The nanosheets of ZnO:I nanocrsytallites were proven to be positive in causing light scattering in a broad wavelength region and, therefore, enhancing the light harvesting capability of the photoelectrode film and thus, promotes the solar cell performance. The fabricated cells exhibited highly durable cell performances, even after a month under atmospheric conditions. Electrochemical impedance spectroscopy (EIS) data confirmed that iodine doping was helpful to lower the recombination resistance and prolonged electron lifetime of the ZnO:I cells, hence diminishing the recombination process. The efficiency achieved for the best DSSC in this work was much better than ever reported for a ZnO-based DSSC. PMID:23510487

Mahmood, Khalid; Kang, Hyun Wook; Park, Seung Bin; Sung, Hyung Jin

2013-04-02

310

A polysaccharide fraction from medicinal herb Prunella vulgaris downregulates the expression of herpes simplex virus antigen in Vero cells  

Microsoft Academic Search

Herpes simplex viruses (HSV) are pathogenic. With the emergence of drug-resistant strains of HSV, new antiviral agents, especially those with different modes of action, are urgently needed. Prunella vulgaris L. (Labiatae), a perennial plant commonly found in China and Europe, has long been used as a folk medicine to cure ailments. In this study, a polysaccharide fraction was prepared from

Lawrence Chi-Ming Chiu; Wen Zhu; Vincent Eng-Choon Ooi

2004-01-01

311

Characterization of the 3a Protein of SARS-associated Coronavirus in Infected Vero E6 Cells and SARS Patients  

Microsoft Academic Search

Proteomics was used to identify a protein encoded by ORF 3a in a SARS-associated coronavirus (SARS-CoV). Immuno-blotting revealed that interchain disulfide bonds might be formed between this protein and the spike protein. ELISA indicated that sera from SARS patients have significant positive reactions with synthesized peptides derived from the 3a protein. These results are concordant with that of a spike

Rong Zeng; Rui-Fu Yang; Mu-De Shi; Man-Rong Jiang; You-Hua Xie; Hong-Qiang Ruan; Xiao-Sheng Jiang; Lv Shi; Hu Zhou; Lei Zhang; Xiao-Dong Wu; Ying Lin; Yong-Yong Ji; Lei Xiong; Yan Jin; Er-Hei Dai; Xiao-Yi Wang; Bin-Ying Si; Jin Wang; Hong-Xia Wang; Cui-E Wang; Yong-Hua Gan; Yu-Chuan Li; Ju-Tian Cao; Jiang-Ping Zuo; Shi-Fang Shan; En Xie; Song-Hua Chen; Zhi-Qin Jiang; Xi Zhang; Yuan Wang; Gang Pei; Bing Sun; Jia-Rui Wu

2004-01-01

312

Virological and Serological Findings in Rousettus aegyptiacus Experimentally Inoculated with Vero Cells-Adapted Hogan Strain of Marburg Virus  

PubMed Central

The Egyptian fruit bat, Rousettus aegyptiacus, is currently regarded as a potential reservoir host for Marburg virus (MARV). However, the modes of transmission, the level of viral replication, tissue tropism and viral shedding pattern remains to be described. Captive-bred R. aegyptiacus, including adult males, females and pups were exposed to MARV by different inoculation routes. Blood, tissues, feces and urine from 9 bats inoculated by combination of nasal and oral routes were all negative for the virus and ELISA IgG antibody could not be demonstrated for up to 21 days post inoculation (p.i.). In 21 bats inoculated by a combination of intraperitoneal/subcutaneous route, viremia and the presence of MARV in different tissues was detected on days 2–9 p.i., and IgG antibody on days 9–21 p.i. In 3 bats inoculated subcutaneously, viremia was detected on days 5 and 8 (termination of experiment), with virus isolation from different organs. MARV could not be detected in urine, feces or oral swabs in any of the 3 experimental groups. However, it was detected in tissues which might contribute to horizontal or vertical transmission, e.g. lung, intestines, kidney, bladder, salivary glands, and female reproductive tract. Viremia lasting at least 5 days could also facilitate MARV mechanical transmission by blood sucking arthropods and infections of susceptible vertebrate hosts by direct contact with infected blood. All bats were clinically normal and no gross pathology was identified on post mortem examination. This work confirms the susceptibility of R. aegyptiacus to infection with MARV irrespective of sex and age and contributes to establishing a bat-filovirus experimental model. Further studies are required to uncover the mode of MARV transmission, and to investigate the putative role of R. aegyptiacus as a reservoir host.

Paweska, Janusz T.; Jansen van Vuren, Petrus; Masumu, Justin; Leman, Patricia A.; Grobbelaar, Antoinette A.; Birkhead, Monica; Clift, Sarah; Swanepoel, Robert; Kemp, Alan

2012-01-01

313

Antiviral and cytotoxic activity of netropsin derivatives in vero cells infected with vaccinia virus and herpes simplex virus type I  

Microsoft Academic Search

Currently, the population has not been vaccinated against variola virus; as a result, children and the majority of adult population younger than 27?30 years old are not immune to smallpox. In view of this, designing and synthesis of new compound that can effectively inhibit reproduction of orthopox viruses is a relevant problem of both theoretical and practical significance. The relevance

V. L. Andronova; S. L. Grokhovsky; A. N. Surovaya; V. S. Arkhipova; G. V. Gursky; G. A. Galegov

2008-01-01

314

A new isoflavone glycitein 7-O-beta-D-glucoside 4''-O-methylate, isolated from Cordyceps militaris grown on germinated soybeans extract, inhibits EGF-induced mucus hypersecretion in the human lung mucoepidermoid cells.  

PubMed

A new isoflavone glycitein 7-O-beta-d-glucoside 4''-O-methylate (CGLM) has been isolated recently from Cordyceps militaris grown on germinated soybean extract and has antioxidant activity. In the present study, CGLM was investigated for its suppression of airway mucous hyper-secretion in epidermal growth factor (EGF)-treated human lung mucoepidermoid cells. NCI-H292 cells were treated with CGLM for 1?h, followed by EGF treatment for 24?h. The decrease in cyclooxygenase-2 (COX-2) production was correlated with reduced levels of protein and mRNA of inducible matrix metalloproteinase 9 (MMP-9) and also MUC5AC gene expression. CGLM directly inhibited down-regulated NF-?B activity, and significantly inhibited the phosphorylation of p38 and ERK1/2 (p42/p44) in NCI-H292 cells. These results suggest that CGLM protects NCI-H292 cells from EGF-induced damage by down-regulation of COX-2, MMP-9 and MUC5AC gene expression, mediated via blocking the NF-kappa-B and p38/ERK MAPK pathways. PMID:22407817

Kim, Jung-Hee; Park, Dong Ki; Lee, Choong Hwan; Yoon, Do-Young

2012-03-09

315

A Molecular Mimic of Phosphorylated Prolactin Markedly Reduced Tumor Incidence and Size When DU145 Human Prostate Cancer Cells Were Grown in Nude Mice1  

Microsoft Academic Search

Others have demonstrated the presence of an autocrine prolactin (PRL) growth loop in the normal human prostate. In this study we have used three human prostate cancer cell lines but have focused on the androgen- independent human prostate cancer cell line, DU145, to ask: (a) whether this autocrine growth loop is maintained beyond the loss of androgen sensitivity in the

Xiaolei Xu; Eva Kreye; C. Benson Kuo; Ameae M. Walker

2001-01-01

316

Autologous transplantation of ex vivo expanded bone marrow cells grown from small aliquots after high-dose chemotherapy for breast cancer  

Microsoft Academic Search

The collection of small aliquots of bone marrow (BM), followed by ex vivo expan- sion for autologous transplantation may be less morbid, and more cost-effective, than typical BM or blood stem cell harvesting. Passive elimination of con- taminating tumor cells during expansion could reduce reinoculation risks. Nine- teen breast cancer patients underwent autotransplants exclusively using ex vivo expanded small aliquot

Patrick Stiff; Bohao Chen; Wilbur Franklin; David Oldenberg; Eric Hsi; Robert Bayer; Elizabeth Shpall; Judy Douville; Ramkumar Mandalam; Deepak Malhotra; Thomas Muller; R. Douglas; Alan Smith

317

Synergistic effect of CMP/KDO synthase inhibitors with antimicrobial agents on inhibition of production and release of Vero toxin by enterohaemorrhagic Escherichia coli O157:H7.  

PubMed

Synergistic effect of CMP/KDO synthase inhibitors in LPS biosynthesis of Gram-negative bacteria with kanamycin (KM) and fosfomycin (FOM) on the production and release of Vero toxins (VTs) by Escherichia coli O157 was evaluated in vitro. While CMP/KDO synthase inhibitors, KM and FOM showed no inhibitory effect on the production/release of VTs by themselves alone, both KM and FOM showed the remarkable inhibition of VT2 release through synergistic collaboration with CMP:KDO synthase inhibitor. PMID:14698183

Kondo, Ken-ichiro; Doi, Hiroyasu; Adachi, Hayamitsu; Nishimura, Yoshio

2004-01-19

318

Establishment of cell lines with increased susceptibility to EV71/CA16 by stable overexpression of SCARB2  

PubMed Central

Background Human enterovirus type 71 (EV71) and Coxsackievirus A group type 16 (CA16) belong to human Enterovirus species A of the family Picornaviridae. These viruses are recognized as the major pathogens responsible for epidemics of hand-foot-mouth disease (HFMD), which presents with fever and vesicular eruptions of palms, soles of the feet or mouth. Human scavenger receptor class B, member 2 (SCARB2) has been identified as the receptor for both EV71 and CA16, as overexpression of SCARB2 in cells can enhance virus replication significantly. Methods In this study, we used a lentivirus packaging vector to transduce the SCARB2 gene into human embryonic kidney cells (293), human rhabdomyosarcoma cells (RD) and African green monkey kidney cells (Vero) to create stable expression lines. Expression of SCARB2 in the resulting three transgenic cell lines was confirmed by real-time RT-PCR, immunofluorescence and flow cytometry. Results Levels of SCARB2 mRNA determined by real-time RT-PCR in 293-SCARB2 (293S) or RD-SCARB2 (RDS) transgenic cell lines were approximately 2?×?102 times higher than those in 293 and RD cells, respectively, and three times higher in Vero-SCARB2 (VeroS) than in Vero cells. Furthermore, EV71 and CA16 virus titers in 293S and RDS cells were 102–103-fold higher (detected in RD cell) than those in the parental cells, and a 10-fold higher titer of EV71 was achieved in VeroS cells compared with that in Vero cells. Conclusions We established for the first time three cell lines stably overexpressing SCARB2, which showed drastic increases in susceptibility to EV71/CA16 infection. These optimal cell lines may be utilized to develop inactivated vaccines for EV71/CA16 and facilitate rapid detection and isolation of HFMD pathogens or other Enterovirus serotypes. Furthermore, these stable cell lines also can serve as tools to facilitate drug screenings as well as molecular studies on virus-host interactions and pathogenesis of causative agents for HFMD.

2013-01-01

319

Effects of 16,16-dimethyl prostaglandin E 2 on glycoprotein and lipid synthesis of gastric epithelial cells grown in a primary culture  

Microsoft Academic Search

Summary  We investigated the biosynthesis of phospholipid, neutral lipids, glycoproteins, and DNA in primary cultures of rat oxyntic\\u000a mucosal cells. In addition, responses of these biosynthetic pathways to the gastric protective agent 16,16-dimethyl prostaglandin\\u000a E2 (dmPGE2) were studied. Cultured gastric cells under control conditions synthesized glycoprotein in a linear manner over time. The\\u000a cells responded to dmPGE2 with an increase in

Elizabeth J. Dial; Ya-Chu J. Kao; Lenard M. Lichtenberger

1991-01-01

320

Role of P13 Kinase Signaling Pathways in Polarity Determination of Human Mammary Epithelial Cells Grown in Three-Dimensional Extracellular Matrix.  

National Technical Information Service (NTIS)

Loss of tissue polarity and increased proliferation are the characteristic alterations of the breast tumor phenotype. To investigate these processes, we have used a three-dimensional (3D) culture system in which malignant human breast cells can be reverte...

H. Liu

2004-01-01

321

Similarity in Several Properties of Psychrophilic Bacteria Grown at Low and Moderate Temperatures1  

PubMed Central

Several properties of psychrophilic pseudomonads were studied with cells grown in batch culture in nutrient broth at 2 and 30 C. No differences were observed in the size, catalase activity, deoxyribonucleic acid, ribonucleic acid, or protein content of cells grown at either temperature. The importance of comparing physiologically similar cells is discussed. Images

Frank, Hilmer A.; Reid, Ann; Santo, Leatrice M.; Lum, Norma A.; Sandler, Sandra T.

1972-01-01

322

Studies on the respiratory system of aerobically (Dark) and anaerobically (Light) grown Rhodospirillum rubrum  

Microsoft Academic Search

1.A major part of the respiratory activity of light grown cells of Rhodospirillum rubrum is associated with a system identical with that found in dark grown cells.2.The specific activity of NADH and succinate dehydrogenase and cytochrome c reductase on a protein basis is the same in the particulate fraction from photosynthetic and aerobic cells. In contrast, the NADH and succinate

A. Thore; D. L. Keister; A. San Pietro

1969-01-01

323

Effects of 12-O-tetradecanoylphorbol-13-acetate in combination with gemcitabine on Panc-1 pancreatic cancer cells cultured in vitro or Panc-1 tumors grown in immunodeficient mice.  

PubMed

In the present study, the effects of 12-O-tetra-decanoylphorbol-13-acetate (TPA) alone or in combination with gemcitabine on the growth of Panc-1 pancreatic cancer cells cultured in vitro or grown in NCr immunodeficient nude mice were investigated. Combinations of TPA and gemcitabine synergi-stically inhibited the growth and induced apoptosis in Panc-1 cells. The combination of TPA (0.16 nM) and gemcitabine (0.5 µM) induced a marked increase in phosphorylated c-Jun NH2-terminal kinase (JNK) in the Panc-1 cells. In animal experiments, NCr nude mice with established Panc-1 tumors received daily intraperitoneal (i.p.) injections of TPA (50 ng/g body weight/day) or gemcitabine (0.5 µg/g body weight/day) alone or in combination for 26 days. Treatment with daily i.p. injections of low doses of TPA or gemcitabine alone had a modest inhibitory effect on the growth of the tumors. However, the combination of low doses of TPA and gemcitabine more potently inhibited the growth of Panc-1 tumors than either agent used individually. Treatment with TPA or gemcitabine alone or in combination did not affect the body weight of the animals. Clinical trials with TPA alone or in combination with gemcitabine on patients with pancreatic cancer are warranted in order to confirm our results. PMID:23041978

Zheng, Xi; Cui, Xiao-Xing; Gao, Zhi; Verano, Michael; Huang, Mou-Tuan; Liu, Yue; Rabson, Arnold B; Conney, Allan H

2012-10-04

324

Protein and phosphoprotein levels in glioma and adenocarcinoma cell lines grown in normoxia and hypoxia in monolayer and three-dimensional cultures  

PubMed Central

Background Three dimensional (3D) growths of cancer cells in vitro are more reflective of in situ cancer cell growth than growth in monolayer (2D). The present study is designed to determine changes in protein and phosphoprotein that reflect adaptation of tumor cells to 3D as compared to 2D. Since relative hypoxia is a common feature of most solid tumors, the present study also aims to look at the impact of transition from normoxia to hypoxia in these two growth conditions. Results Using reverse-phase protein arrays, we compared levels of 121 different phosphorylated and non-phosphorylated proteins in 5 glioma and 6 adenocarcinoma lines under conditions of 3D and monolayer culture in normoxia and hypoxia. A three-way analysis of variance showed levels of 82 antibodies differed between media (2D vs. 3D) and 49 differed between treatments (hypoxia vs. normoxia). Comparing 2D to 3D growth, 7 proteins were commonly (i.e., > 50% of tumors) elevated in 3D: FAK, AKT, Src, GSK3??, TSC2, p38, and NF??p65. Conversely, 7 other proteins are commonly decreased: ATRIP, ATR, ?-catenin, BCL-X, cyclin B1, Egr-1, and HIF-1?. Comparing normoxia to hypoxia, only NCKIPSD was commonly elevated in hypoxia; 6 proteins were decreased: cyclin B1, 4EBP1(Ser65), c-Myc, SMAD3(Ser423), S6(Ser235), and S6(Ser240). Hypoxia affected glioma cell lines differently from adenocarcinoma cell lines: 8 proteins were increased in gliomas (BAX, caspase 7, HIF-1?, c-JUN, MEK1, PARP 1 cleaved, Src, and VEGFR2) and none in adenocarcinomas. Conclusions We identified subsets of proteins with clearly concordant/discordant behavior between gliomas and adenocarcinomas. In general, monolayer to 3D culture differences are clearer than normoxia to hypoxia differences, with anti-apoptotic, cytoskeletal rearrangement and cell survival pathways emphasized in the former and mTOR pathway, transcription, cell-cycle arrest modulation, and increased cell motility in the latter.

2012-01-01

325

A Novel Culture System Shows that Stem Cells Can be Grown in 3D and Under Physiologic Pulsatile Conditions for Tissue Engineering of Vascular Grafts  

Microsoft Academic Search

Background. Currently available vascular grafts have been limited by variable patency rates, material avail- ability, and immunological rejection. The creation of a tissue-engineered vascular graft (TEVG) from autolo- gous stem cells would potentially overcome these limi- tations. As a first step in creating a completely autolo- gous TEVG, our objective was to develop a novel system for culturing undifferentiated mouse

Peyman Benharash; Mahncy Mehrotra

2006-01-01

326

Growth characteristics and protein profiles of prototype and wild-type rat coronavirus isolates grown in a cloned subline of mouse fibroblasts (L2p.176 cells)  

Microsoft Academic Search

Rat coronaviruses (RCVs) infect laboratory rats and confound biomedical research results. In vitro systems developed so far have limited the growth in knowledge about RCVs by not permitting generation of plaque-cloned virus stocks, reliable isolation of RCVs from rat tissues, or growth of high titered stocks of all isolates. Due to the fact that less than 20% of L2(Percy) cells

Diane J. Gaertner; Susan R. Compton; Deborah F. Winograd; Abigail L. Smith

1996-01-01

327

Ion distribution measured by electron probe X-ray microanalysis in apoplastic and symplastic pathways in root cells in sunflower plants grown in saline medium.  

PubMed

Little is known about how salinity affects ions distribution in root apoplast and symplast. Using x-ray microanalysis, ions distribution and the relative contribution of apoplastic and symplastic pathways for delivery of ions to root xylem were studied in sunflower plants exposed to moderate salinity (EC=6). Cortical cells provided a considerably extended Na(+) and Cl(-) storage facility. Their contents are greater in cytoplasm (root symplast) as compared to those in intercellular spaces (root apoplast). Hence, in this level of salinity, salt damage in sunflower is not dehydration due to extracellular accumulation of sodium and chloride ions, as suggested in the Oertli hypothesis. On the other hand, reduction in calcium content due to salinity in intercellular space is less than reduction in the cytoplasm of cortical cells. It seems that sodium inhibits the radial movement of calcium in symplastic pathway more than in the apoplastic pathway. The cell wall seems to have an important role in providing calcium for the apoplastic pathway. Redistribution of calcium from the cell wall to intercellular space is because of its tendency towards xylem through the apoplastic pathway. This might be a strategy to enhance loading of calcium to xylem elements and to reduce calcium deficiency in young leaves under salinity. This phenomenon may be able to increase salt tolerance in sunflower plants. Supplemental calcium has been found to be effective in reducing radial transport of Na(+) across the root cells and their loading into the xylem, but not sodium absorption. Supplemental calcium enhanced Ca(2+) uptake and influx into roots and transport to stele. PMID:22922196

Ebrahimi, Reza; Bhatla, S C

2012-09-01

328

Infection with Langat Flavivirus or expression of the envelope protein induces apoptotic cell death.  

PubMed

Langat (LGT) flavivirus, derived from infectious full-length cDNA clone 636, was investigated for its apoptotic activities in mouse neuroblastoma (Neuro-2a) and simian kidney (Vero and LLC-MK(2)) cells. The hallmark of apoptosis, cleavage of cellular DNA, was observed 48 h after infection of Vero, LLC-MK(2), and Neuro-2a cells by electrophoresis analysis. Apoptosis in infected cells was also confirmed by TUNEL assay. LGT-infected Neuro-2a cells showed an increase in caspase-3-like protease (DEVDase) activity. Expression of the major envelope glycoprotein (E) alone reduced cell viability in both Vero and Neuro-2a cells, and the baculovirus P35 protein, which inhibits multiple caspases, completely blocked this effect. Cleavage of cellular DNA was observed in E gene-transfected Vero cells by TUNEL assay. Expression of E protein or caspase-9 resulted in activation of caspase-3-like proteases in Neuro-2a cells. The caspase-3-like protease specific inhibitor, Ac-DEVD-CHO peptide, partially inhibited E protein- or caspase-9-induced apoptosis in Neuro-2a cells. These observations indicate that infection of cells with LGT virus or expression of LGT virus E protein induces apoptosis through a caspase-3-like protease pathway. PMID:11485400

Prikhod'ko, G G; Prikhod'ko, E A; Cohen, J I; Pletnev, A G

2001-08-01

329

Alterations of leaf cell ultrastructures and AFLP DNA profiles in Earth-grown tomato plants propagated from long-term six years Mir-flown seeds  

Microsoft Academic Search

Leaf cell ultrastructures and DNA variations in the firstand the second-generation of Earthgrown tomato (Lycopersicon esculentun Mill) plants that had been endured a long-term six years spaceflight in the Mir were compared to their ground-based control plants, under observations with a Transmission Electron Microscope and the Amplification Fragment Length Polymorphism (AFLP) analysis. For alterations in the morphological ultrastructures, one plant

Min Liu; Huai Xue; Yi Pan; Chunhua Zhang; Jinying Lu

2008-01-01

330

Choline metabolism and membrane formation in rat hepatoma cells grown in suspension culture. 111. Choline transport and uptake by simple diffusion and lack of direct exchange with phosphatidylcholine  

Microsoft Academic Search

The initial rate of incorporation of methyl- labeled choline into the acid-soluble pool (phosphorylcholine) of Novikoff hepatoma cells growing in suspension culture was investigated as a function of the choline concentration in the medium. Below, but not above, 20 PM, choline incorporation followed simple Michaelis-Menten kinetics at 24, 33, or 37OC with an apparent K, of 4-7 PM, and the

PETER G. W. PLAGEMAEN

331

Photocurrent enhancement in In0.53Ga0.47As solar cells grown on InP\\/SiO2\\/Si transferred epitaxial templates  

Microsoft Academic Search

InP\\/Si engineered substrates formed by wafer bonding and layer transfer have the potential to significantly reduce the cost and weight of III-V compound semiconductor solar cells. InP\\/Si substrates were prepared by He implantation of InP prior to bonding to a thermally oxidized Si substrate and annealing to exfoliate an InP thin film. Following thinning of the transferred InP film to

James M. Zahler; Katsuaki Tanabe; Corinne Ladous; Tom Pinnington; Frederick D. Newman; Harry A. Atwater

2007-01-01

332

Nucleolus in clinostat-grown plants  

SciTech Connect

The clinostat is an apparatus that is used to mimic zero gravity in studies of plant growth in the absence of gravitropic response. Clinostat-grown tissue cultures of carrot exhibit significant increases both in the number of nuclei containing more than one nucleolus and in nucleolar volume. Oat seedlings germinated and grown on clinostats exhibit a decreased rate of shoot elongation, increased tissue sensitivity to applied auxin, and an increased response to gravitropic stimulation. Clinostat treatment clearly affects plant metabolism. The nucleolus is the region in the nucleus where ribosome synthesis and assembly take place. The 18S, 5.8S, and 25S ribosomal genes, in tandem units, are located in the nucleolus. Ribosomes orchestrate the production of all proteins that are necessary for the maintenance of cell growth, development, and survival. A full study of the effects of nullification of gravitropism, by clinostat rotation, on nucleolar development in barley has been initiated. The authors study developmental changes of nucleolar number and diameter in clinostat-grown root tissues. Preliminary results show that barley roots exhibit changes in nucleolar number and diameter. Growth rates of barley root and shoot also appear to be reduced, in measurements of both length and weight.

Shen-Miller, J.; Dannenhoffer, J. (Univ. of California, Los Angeles (United States)); Hinchman, R. (Argonne National Lab., IL (United States))

1991-05-01

333

[Growth of Coxiella burnetii in selected cell cultures].  

PubMed

Usefulness of monolayer cell cultures for C. burnetii multiplication was evaluated. Continuous Vero cell line and primary cell (cultures cell culture of monkey kidney Cercopithecus aethiops, cell culture of chicken fibroblasts, diploid cell line of human embryo) was inoculated for this purpose. Two Coxiella burnetii strains suspensions were used as inoculum of standard Henzerling strain and Zamo?? strain isolated from an area of Poland. Primary cell lines were characterized by considerable degree of sensitivity to, C. burnetii infection, and at the same time, the most sensitive was the line derived from monkey kidney. Progressive vacuolisation of infected culture cells was designated as cytopathic effect. Henzerling strain showed higher infectivity (4.7 x 10(8) PFU/ml) for chicken fibroblasts as compared to Zamo?? strain (8.7 x 10(6) PFU/ml). On the other hand both strains induced cytopathic effect in Vero cell line without degeneration of host cells. PMID:2087134

Rumin, W; Kruszewska, D; Sadowski, W; Tylewska-Wierzbanowska, S

1990-01-01

334

The application of bovine brain microvessel endothelial-cell monolayers grown onto polycarbonate membranes in vitro to estimate the potential permeability of solutes through the blood-brain barrier.  

PubMed

Previously our laboratory (Rim et al., Int. J. Pharm. 32:79-84. 1986) described an in vitro blood-brain barrier (BBB) model consisting of cultured bovine brain microvessel endothelial cells (BMECs) grown onto regenerated cellulose acetate membranes. However, the utility of this in vitro BBB model system was limited because the regenerated cellulose acetate membrane and not the monolayer of bovine BMECs was rate limiting for the permeability of very lipophilic compounds. Therefore, in this study we have evaluated polycarbonate membranes as supports for growing bovine BMECs and for conducting in vitro drug permeability studies. Bovine BMECs were cultured on collagen-coated polycarbonate membranes (13-mm diameter, 12-microns pore size) which were then mounted into side-by-side diffusion cells for transport studies. The permeabilities of a series of solutes of varying lipophilicity (progesterone, estrone, testosterone, haloperidol, propranolol, antipyrine, caffeine, urea, acyclovir, ganciclovir, ribavirin, and glycerol) were determined and an excellent correlation (r = 0.97) was established between the permeability coefficients of the solutes and their log partition coefficients (PC)/(MW)1/2. These results suggest that bovine BMECs cultured onto polycarbonate membranes can be used as an in vitro model system for estimating the potential permeability of a solute through the BBB in vivo. PMID:2798313

Shah, M V; Audus, K L; Borchardt, R T

1989-07-01

335

In situ grown vertically oriented CuInS2 nanosheets and their high catalytic activity as counter electrodes in dye-sensitized solar cells.  

PubMed

Vertically oriented CuInS(2) nanosheet thin films were prepared via a facile one-step solvothermal process and used in dye-sensitized solar cells (DSSCs) as counter electrodes. The catalytic activity of the CuInS(2) films based on different precursor concentrations was investigated using electrochemical methods. DSSCs based on optimized CuInS(2) thin film as counter electrodes reached a power conversion efficiency of 6.33%, comparable to that of sputtering Pt (6.07%). PMID:23388681

Yang, Jie; Bao, Chunxiong; Zhang, Jiyuan; Yu, Tao; Huang, Huan; Wei, Yulong; Gao, Hao; Fu, Gao; Liu, Jianguo; Zou, Zhigang

2013-03-11

336

Detection of the quantity of kinesin and microgravity-sensitive kinesin genes in rat bone marrow stromal cells grown in a simulated microgravity environment  

NASA Astrophysics Data System (ADS)

Kinesin and kinesin-like proteins (KLPs) constitute a superfamily of microtubule motor proteins found in all eukaryotic organisms. Members of the kinesin superfamily are known to play important roles in many fundamental cellular and developmental processes. To date, few published studies have reported on the effects of microgravity on kinesin expression. In this paper, we describe the expression pattern and microgravity-sensitive genes of kinesin in rat bone marrow stromal cells cultured in a ground-based rotating bioreactor. The quantity of kinesin under the clinorotation condition was examined by immunoblot analysis with anti-kinesin. Furthermore, the distribution of kinesin at various times during clinorotation was determined by dual immunostaining, using anti-kinesin monoclonal antibody or anti-?-tubulin monoclonal antibody. In terms of kinesin quantity, we found that the ratios of the amounts of clinorotated/stationary KLPs decreased from clinorotation day 5 to day 10, although it increased on days 2 and 3. Immunofluorescence analysis revealed that kinesin in the nucleus was the first to be affected by simulated microgravity, following the kinesin at the periphery that was affected at various times during clinorotation. Real-time RT-PCR analysis of kinesin mRNA expression was performed and led to the identification of 3 microgravity-sensitive kinesin genes: KIF9, KIFC1, and KIF21A. Our results suggest that kinesin has a distinct expression pattern, and the identification of microgravity-sensitive kinesin genes offers insight into fundamental cell biology.

Ni, Chengzhi; Wang, Chunyan; Li, Yuan; Li, Yinghui; Dai, Zhongquan; Zhao, Dongming; Sun, Hongyi; Wu, Bin

2011-06-01

337

Fermentation characteristics of Fusariumoxysporum grown on acetate.  

PubMed

In this study, the growth characteristics of Fusariumoxysporum were evaluated in minimal medium using acetate or different mixtures of acetate and glucose as carbon source. The minimum inhibitory concentration (MIC) of acetic acid that F.oxysporum cells could tolerate was 0.8%w/v while glucose was consumed preferentially to acetate. The activity of isocitrate lyase was high when cells were grown on acetate and acetate plus glucose indicating an activation of the glyoxylate cycle. Investigation of the metabolic fingerprinting and footprinting revealed higher levels of intracellular and extracellular TCA cycle intermediates when F.oxysporum cells were grown on mixtures of acetate and glucose compared to growth on only glucose. Our data support the hypothesis that a higher flux through TCA cycle during acetate consumption could significantly increase the pool of NADH, resulting in the activation of succinate-propionate pathway which consumes reducing power (NADH) via conversion of succinate to propionyl-CoA and produce propionate. PMID:18304808

Panagiotou, Gianni; Pachidou, Fotini; Petroutsos, Dimitris; Olsson, Lisbeth; Christakopoulos, Paul

2008-03-04

338

Formation Mechanism of Crack and Pore Occurred in a Zirconia Electrolyte Film Having Solid Oxide Fuel Cell Grown by ECR Plasma CVD Method  

NASA Astrophysics Data System (ADS)

Formation mechanism of a crack and pore occurred in zirconia electrolyte film having solid oxide fuel cell, that the film prepared by the microwave plasma-enhanced chemical vapor deposition, was studied based on dependence on annealing treatment and substrate temperature. It is found that a crack and pore is restrained at annealing treatment in a vacuum, although it occurs in atmospheric. A crack is formed at grain boundary by occurrence of pore in the film, and a large crack observes at a higher substrate temperature. Moreover in the film prepared without substrate heating, a crack and pore did not also occur at annealing treatment. As a result, it is supposed that formation of a crack and pore is occurred at getting oxygen gas or moisture in atmospheric into the film.

Semizo, Makoto; Miich, Tomoaki; Nagata, Akiyoshi

339

Enhancement of chemotaxis in Spirochaeta aurantia grown under conditions of nutrient limitation.  

PubMed Central

Spirochaeta aurantia M1 cells were grown in a chemostat under conditions of energy and carbon source limitation. The chemotactic responses of the chemostat-grown cells were compared with those of S. aurantia cells grown in batch culture in the presence of excess energy and carbon source. Chemotactic responses were measured by determining the number of cells that entered a capillary tube containing a solution of attractant. S. aurantia cells grown in the chemostat under energy and carbon source limitation exhibited enhanced chemotactic responses and detected lower concentrations of attractant, as compared with cells grown in batch culture. The chemotactic response toward an attractant was specifically enhanced when that attractant was the growth-limiting energy and carbon source. The medium used contained either D-glucose or D-xylose as the sole energy and carbon source. Cells had the greatest chemotactic response toward glucose when grown at a dilution rate (D) of 0.045 h-1 under glucose limitation and toward xylose when grown at D = 0.06 h-1 under xylose limitation. When cells were grown under glucose limitation (D = 0.045 h-1), they sensed concentrations of attractant (glucose) ca. 1,000 times lower than those sensed by batch-grown cells. A similar enhancement of sensing ability (toward xylose) was observed in cells grown under xylose limitation. The results indicated that S. aurantia cells are able to regulate their chemosensory system in response to nutrient limitation. Maximum enhancement of chemotaxis occurs in cells growing at very low concentrations of energy and carbon source. Most likely, this property provides the spirochetes with competitive advantages when the availability of nutrients becomes severely limited in their habitats.

Terracciano, J S; Canale-Parola, E

1984-01-01

340

The initiation of neurite outgrowth by sympathetic neurons grown in vitro does not depend on assembly of microtubules [published erratum appears in J Cell Biol 1995 Feb;128(3):443  

PubMed Central

Neurite formation by dissociated chick sympathetic neurons in vitro begins when one of the many filopodia that emanate from the cell body of a neuron is invaded by cytoplasm containing microtubules and other components of axoplasm (Smith, 1994). This study was undertaken to determine whether this process depends on assembly of microtubules. To inhibit microtubule assembly, neurons were grown in medium containing nocodazole or colchicine. In one series of experiments, neurons first were exposed to the microtubule-stabilizing drug, taxol, so that existing microtubules would remain intact while assembly of new microtubules was inhibited. The ability of neurons to form neurites was assessed by time-lapse video microscopy. Neurons subsequently were stained with antibodies against the tyrosinated and acetylated forms of alpha-tubulin and examined by laser confocal microscopy to visualize microtubules. Neurons were able to form short processes despite inhibition of microtubule assembly and they did so in a way that closely resembled process formation in control medium. Processes formed by neurons that had not been pretreated with taxol were devoid of microtubules. However, microtubules were present in processes of taxol- pretreated neurons. These microtubules contained acetylated alpha- tubulin, as is typical of stable microtubules, but not tyrosinated alpha-tubulin, the form present in recently assembled microtubules. These findings show that the initial steps in neurite formation do not depend on microtubule assembly and suggest that microtubules assembled in the cell body can be translocated into developing neurites as they emerge. The results are compatible with models of neurite formation which postulate that cytoplasm from the cell body is transported into filopodia by actomyosin-based motility mechanisms.

1994-01-01

341

Carbon-13 nuclear-magnetic-resonance spectroscopy of whole cells and of cytochrome C from Neurospora crass grown with (S-Me-13C)methionine.  

PubMed Central

Neurospora crassa cytochrome C biosynthetically labelled with [S-Me-13C]methionine was prepared and analysed by 13C nuclear-magnetic-resonance spectroscopy. The methyl group of methionine is extensively incorporated into an N-trimethyl-lysine-72 residue arise from S-adenosylmethionine transmethylation, and that the methyl carbons of methionine residues are sufficiently close to the haem centre to experience chemical shifts from the ring currents of the tetrapyrrole pi electrons and broadening due to binding of methionine-80 with the haem, as well as interaction of the S-E113C]methyl groups with the paramagnetic iron centre. Although whole cells of the labelled Neurospora produced a 13C resonance at the expected position for the methionyl methyl group most of the methyl label was diverted into N-tetra-alkyl ammonium compounds. After an active state of growth these labelled N-methyl compounds appear, in the main, to be low-molecular-weight derivatives of choline which, if associated with membrane, are in a sufficiently fluid environment to have short rotational correlation times. During a subsequent dormant growth period these compounds become associated to some extent with relatively more immobile phases as a result of membrane binding or an increase in membrane rigidity.

Eakin, R T; Morgan, L O

1975-01-01

342

RICKETTSIAL PHOSPHOLIPASE A 2 AS A PATHOGENIC MECHANISM IN A MODEL OF CELL INJURY BY TYPHUS AND SPOTTED FEVER GROUP RICKETTSIAE  

Microsoft Academic Search

Phospholipase A2 activity by typhus group rickettsiae causes hemolysis in vitro. Rickettsial phospholi- pase A2 has been proposed to mediate entry into the host cell, escape from the phagosome, and cause injury to host cells by both typhus and spotted fever group rickettsiae. In a rickettsial contact-associated cytotoxicity model, the interaction of Rickettsia prowazekii or R. conorii with Vero cells

DAVID H. WALKER; HUI-MIN FENG; VSEVOLOD L. POPOV

2001-01-01

343

Immunocytochemical study on the cytoplasmic side of cell membranes infected with vesicular stomatitis virus by quick-freezing and deep-etching replica method  

Microsoft Academic Search

Summary Synthesized N protein of vesicular stomatitis virus (VSV) is associated with replicated viral genomes in the infected cells. The cytoplasmic side of cell membranes was examined by quick-freezing and deep-etching replica method, in order to clarify the localization of VSV genomes. Control or infected monolayer Vero cells were fixed in 2% paraformaldehyde, scraped and centrifuged to make pellets. A

S. Ohno

1985-01-01

344

Feasibility evaluation of a new irradiation technique: three-dimensional unicursal irradiation with the Vero4DRT (MHI-TM2000).  

PubMed

The Vero4DRT (MHI-TM2000) is a newly designed unique image-guided radiotherapy system consisting of an O-ring gantry. This system can realize a new irradiation technique in which both the gantry head and O-ring continuously and simultaneously rotate around the inner circumference of the O-ring and the vertical axis of the O-ring, respectively, during irradiation. This technique creates three-dimensional (3D) rotational dynamic conformal arc irradiation, which we term '3D unicursal irradiation'. The aim of this study was to present the concept and to estimate feasibility and potential advantages of the new irradiation technique. Collision maps were developed for the technique and a 3D unicursal plan was experimentally created in reference to the collision map for a pancreatic cancer case. Thereafter, dosimetric comparisons among the 3D unicursal, a two-dimensionally rotational dynamic conformal arc irradiation (2D-DCART), and an intensity-modulated radiation therapy (IMRT) plan were conducted. Dose volume data of the 3D unicursal plan were comparable or improved compared to those of the 2D-DCART and IMRT plans with respect to both the target and the organs at risk. The expected monitor unit (MU) number for the 3D unicursal plan was only 7% higher and 22.1% lower than the MUs for the 2D-DCART plan and IMRT plan, respectively. It is expected that the 3D unicursal irradiation technique has potential advantages in both treatment time and dose distribution, which should be validated under various conditions with a future version of the Vero4DRT fully implemented the function. PMID:22923744

Mizowaki, Takashi; Takayama, Kenji; Nagano, Kazuo; Miyabe, Yuki; Matsuo, Yukinori; Kaneko, Shuji; Kokubo, Masaki; Hiraoka, Masahiro

2012-08-24

345

Feasibility evaluation of a new irradiation technique: three-dimensional unicursal irradiation with the Vero4DRT (MHI-TM2000)  

PubMed Central

The Vero4DRT (MHI-TM2000) is a newly designed unique image-guided radiotherapy system consisting of an O-ring gantry. This system can realize a new irradiation technique in which both the gantry head and O-ring continuously and simultaneously rotate around the inner circumference of the O-ring and the vertical axis of the O-ring, respectively, during irradiation. This technique creates three-dimensional (3D) rotational dynamic conformal arc irradiation, which we term ‘3D unicursal irradiation’. The aim of this study was to present the concept and to estimate feasibility and potential advantages of the new irradiation technique. Collision maps were developed for the technique and a 3D unicursal plan was experimentally created in reference to the collision map for a pancreatic cancer case. Thereafter, dosimetric comparisons among the 3D unicursal, a two-dimensionally rotational dynamic conformal arc irradiation (2D–DCART), and an intensity-modulated radiation therapy (IMRT) plan were conducted. Dose volume data of the 3D unicursal plan were comparable or improved compared to those of the 2D–DCART and IMRT plans with respect to both the target and the organs at risk. The expected monitor unit (MU) number for the 3D unicursal plan was only 7% higher and 22.1% lower than the MUs for the 2D–DCART plan and IMRT plan, respectively. It is expected that the 3D unicursal irradiation technique has potential advantages in both treatment time and dose distribution, which should be validated under various conditions with a future version of the Vero4DRT fully implemented the function.

Mizowaki, Takashi; Takayama, Kenji; Nagano, Kazuo; Miyabe, Yuki; Matsuo, Yukinori; Kaneko, Shuji; Kokubo, Masaki; Hiraoka, Masahiro

2013-01-01

346

Evidence that an internal carbonic anhydrase is present in 5% CO/sub 2/-grown and air-grown Chlamydomonas. [Chlamydomonas reinhardtii  

SciTech Connect

Inorganic carbon (C/sub i/) uptake was measured in wild-type cells of Chlamydomonas reinhardtii, and in cia-3, a mutant strain of C. reinhardtii that cannot grow with air levels of CO/sub 2/. Both air-grown cells, that have a CO/sub 2/ concentrating system, and 5% CO/sub 2/-grown cells that do not have this system, were used. When the external pH was 5.1 or 7.3, air-grown, wild-type cells accumulated inorganic carbon (C/sub i/) and this accumulation was enhanced when the permeant carbonic anhydrase inhibitor, ethoxyzolamide, was added. When the external pH was 5.1, 5% CO/sub 2/-grown cells also accumulated some C/sub i/, although not as much as air-grown cells and this accumulation was stimulated by the addition of ethoxyzolamide. At the same time, ethoxyzolamide inhibited CO/sub 2/ fixation by high CO/sub 2/-grown, wild-type cells at both pH 5.1 and 7.3. These observations imply that 5% CO/sub 2/-grown, wild-type cells, have a physiologically important internal carbonic anhydrase, although the major carbonic anhydrase located in the periplasmic space is only present in air-grown cells. Inorganic carbon uptake by cia-3 cells supported this conclusion. This mutant strain, which is thought to lack an internal carbonic anhydrase, was unaffected by ethoxyzolamide at pH 5.1. Other physiological characteristics of cia-3 resemble those of wild-type cells that have been treated with ethoxyzolamide. It is concluded that an internal carbonic anhydrase is under different regulatory control than the periplasmic carbonic anhydrase.

Moroney, J.V.; Togasaki, R.K.; Husic, H.D.; Tolbert, N.E.

1987-07-01

347

Microevolution of Type 3 Sabin Strain of Poliovirus in Cell Cultures and Its Implications for Oral Poliovirus Vaccine Quality Control  

Microsoft Academic Search

Screening for sequence heterogeneities in Sabin Type 3 strains of attenuated poliovirus demonstrated mutations that consistently accumulate to significant levels following 10 passages in cultures of primary African green monkey kidney (AGMK) cells or continuous cultures of Vero cells. Fourteen newly identified mutations were quantified by mutant analysis by PCR and restriction enzyme cleavage in passages and in batches of

Gennady V. Rezapkin; Laurie P. Norwood; Rolf E. Taffs; Eugenia M. Dragunsky; Inessa S. Levenbook; Konstantin M. Chumakov

1995-01-01

348

Simultaneous Tracking of Capsid, Tegument, and Envelope Protein Localization in Living Cells Infected with Triply Fluorescent Herpes Simplex Virus 1  

Microsoft Academic Search

cyan fluorescent proteins, respectively. The recombinant virus enabled us to monitor the dynamics of these capsid, tegument, and envelope proteins simultaneously in the same live HSV-1-infected cells and to visualize single extracellular virions with three different fluorescent emissions. In Vero cells infected by the triply fluorescent virus, multiple cytoplasmic compartments were found to be induced close to the basal surfaces

Ken Sugimoto; M. Uema; H. Sagara; Michiko Tanaka; T. Sata; Yasuhiro Hashimoto; Yasushi Kawaguchi

2008-01-01

349

Growth characteristics of porcine chlamydial strains in different cell culture systems and comparison with ovine and avian chlamydial strains  

Microsoft Academic Search

Porcine Chlamydiaceae were cultivated under various culture conditions and we compared their growth characteristics with those of ruminant and avian strains.The combination of centrifugation assisted cell culture infection and cycloheximide treatment of Vero cell coverslip cultures provided the highest inclusion numbers with all chlamydial strains. Interestingly, the use of Iscove's modified Dulbecco's medium instead of Eagle's minimal essential medium significantly

Irene Schiller; Andrea Schifferli; Petra Gysling; Andreas Pospischil

2004-01-01

350

Influence of yeast quality on performance of gnotobiotically grown Artemia  

Microsoft Academic Search

Using axenically grown Artemia, a model system was developed to evaluate the effect of bacteria on the survival and development of this crustacean. Two strains of baker's yeast (Saccharomyces cerevisiae) were used in all experiments as feed for Artemia: a wild-type strain and its mnn9 mutant, defective in the synthesis of mannoproteins in the outer cell wall. The genetic background,

Antonio Marques; Jean-Marie François; Jean Dhont; Peter Bossier; Patrick Sorgeloos

2004-01-01

351

Authentication of the R06E Fruit Bat Cell Line  

PubMed Central

Fruit bats and insectivorous bats are believed to provide a natural reservoir for a wide variety of infectious diseases. Several lines of evidence, including the successful isolation of infectious viruses, indicate that Marburg virus and Ravn virus have found a major reservoir in colonies of the Egyptian rousette (Rousettus aegyptiacus). To facilitate molecular studies on virus-reservoir host interactions and isolation of viruses from environmental samples, we established cell lines from primary cells of this animal. The cell lines were given to several laboratories until we realized that a contamination with Vero cells in one of the cultures had occurred. Here we describe a general diagnostic procedure for identification of cross-species contamination with the focus on Vero and Rousettus cell lines, and summarize newly discovered properties of the cell lines that may pertain to pathogen discovery.

Jordan, Ingo; Munster, Vincent J.; Sandig, Volker

2012-01-01

352

Isolation of Hokkaido virus, genus Hantavirus, using a newly established cell line derived from the kidney of the grey red-backed vole (Myodes rufocanus bedfordiae).  

PubMed

Hantaviruses belong to the family Bunyaviridae and are maintained in wild rodents. Although Vero E6 cells, which originate from African green monkey kidney, are used widely in hantavirus research, isolation of hantaviruses from this cell line is difficult. To develop an efficient method of propagation and isolation of hantaviruses we established a novel cell line, MRK101, derived from the kidney of the grey red-backed vole (Myodes rufocanus bedfordiae), the natural host of Hokkaido virus (HOKV). The MRK101 cells showed a significantly higher susceptibility to Puumala virus (PUUV) hosted by Myodes glareolus than Vero E6 cells. Viral nucleocapsid protein in PUUV-infected MRK101 cells was detected earlier than in Vero E6 cells, and the viral titre in the culture fluid of MRK101 cells was higher than that of Vero E6 cells during the early phase of infection. In contrast, MRK101 cells showed no susceptibility to Hantaan virus. HOKV, which has not been isolated to date, was isolated successfully using MRK101 cells. Moreover, the newly isolated HOKV was successfully propagated in MRK101, but not Vero E6, cells. Phylogenic analyses of the S (small), M (medium) and L (large) segment sequences revealed that HOKV is related most closely to PUUV, but is distinct from other hantaviruses. These data suggest that the MRK101 cell line is a useful tool for the isolation and propagation of hantaviruses. Moreover, this is (to our knowledge) the first report of hantavirus isolation in a cell line that originated from the natural host. PMID:22791608

Sanada, Takahiro; Seto, Takahiro; Ozaki, Yuka; Saasa, Ngonda; Yoshimatsu, Kumiko; Arikawa, Jiro; Yoshii, Kentaro; Kariwa, Hiroaki

2012-07-12

353

Thermal stability of corrugated epitaxial graphene grown on Re(0001).  

PubMed

We report on a novel approach to determine the relationship between the corrugation and the thermal stability of epitaxial graphene grown on a strongly interacting substrate. According to our density functional theory calculations, the C single layer grown on Re(0001) is strongly corrugated, with a buckling of 1.6 Å, yielding a simulated C 1s core level spectrum which is in excellent agreement with the experimental one. We found that corrugation is closely knit with the thermal stability of the C network: C-C bond breaking is favored in the strongly buckled regions of the moiré cell, though it requires the presence of diffusing graphene layer vacancies. PMID:21699318

Miniussi, E; Pozzo, M; Baraldi, A; Vesselli, E; Zhan, R R; Comelli, G; Mente?, T O; Niño, M A; Locatelli, A; Lizzit, S; Alfè, D

2011-05-25

354

Thermal Stability of Corrugated Epitaxial Graphene Grown on Re(0001)  

NASA Astrophysics Data System (ADS)

We report on a novel approach to determine the relationship between the corrugation and the thermal stability of epitaxial graphene grown on a strongly interacting substrate. According to our density functional theory calculations, the C single layer grown on Re(0001) is strongly corrugated, with a buckling of 1.6 Å, yielding a simulated C 1s core level spectrum which is in excellent agreement with the experimental one. We found that corrugation is closely knit with the thermal stability of the C network: C-C bond breaking is favored in the strongly buckled regions of the moiré cell, though it requires the presence of diffusing graphene layer vacancies.

Miniussi, E.; Pozzo, M.; Baraldi, A.; Vesselli, E.; Zhan, R. R.; Comelli, G.; Mente?, T. O.; Niño, M. A.; Locatelli, A.; Lizzit, S.; Alfè, D.

2011-05-01

355

Early activation of the mitochondrial apoptotic pathway in Vesicular Stomatitis Virus-infected cells  

Microsoft Academic Search

Vesicular Stomatitis Virus (VSV) has been shown to induce apoptosis in a caspase-dependent manner, but the precise apoptotic pathway remains unknown. We found that caspases 9 and 3, but not caspase 8, were activated during VSV-induced apoptosis in infected Vero cells. Since caspase 9 is related to the mitochondrial apoptotic pathway, we analyzed some mitochondrial events such as changes in

Patricia Gadaleta; Ximena Perfetti; Susana Mersich; Félix Coulombié

2005-01-01

356

Caveolin-1 is incorporated into mature respiratory syncytial virus particles during virus assembly on the surface of virus-infected cells  

Microsoft Academic Search

We have employed immunofluorescence microscopy and transmission electron microscopy to examine the assembly and maturation of respiratory syncytial virus (RSV) in the Vero cell line C1008. RSV matures at the apical cell surface in a filamentous form that extends from the plasma membrane. We observed that inclusion bodies containing viral ribonucleoprotein (RNP) cores predominantly appeared immediately below the plasma membrane,

Gaie Brown; James Aitken; Richard J. Sugrue

357

Chemical surface passivation of silicon nanowires grown by APCVD  

Microsoft Academic Search

Silicon nanowires (SiNWs) are attractive candidate for solar cells and surface passivation has been recognized an important fabrication steps solar cells. The SiNWs were grown on p-type Si (100) substrate by atmospheric pressure chemical vapour deposition. Field emission scanning electron microscopy, Raman spectroscopy and Fourier transform infrared spectroscopy were used to study the atomic bonding and microstructural aspect of silicon

Bhabani S. Swain; Bibhu P. Swain; Nong M. Hwang

2010-01-01

358

The expression of native and cultured RPE grown on different matrices.  

PubMed

The purpose of this work was to determine the expression profiles of retinal pigment epithelial (RPE) cells grown on different matrices and to assess the degree of culture-induced artifact by comparing the profiles to native RPE. Visually confluent ARPE-19 cells were grown on plastic, Matrigel, collagen I, collagen IV, laminin, and fibronectin for 1 wk, and serum was withdrawn for 3 days. Morphologically normal, macular RPE cells were laser-capture microdissected from three human eye globes. Total RNA was extracted from 5,000 cells and reverse transcribed, and radiolabeled cDNA probes were hybridized to an array containing 4,325 known genes. Arrays were assessed by cluster analysis and significance analysis of microarrays (SAM). Real-time RT-PCR was used to validate differentially expressed genes. Despite similar morphology, ARPE-19 demonstrated different expression profiles when grown on different matrices. Cluster analysis showed that cells grown on collagen IV, laminin, and fibronectin had similar profiles that were distinct from cells grown on collagen I. Cells grown on plastic clustered closest to native RPE. This expression pattern was confirmed with supervised cluster analyses. The number of differentially expressed genes, function of differentially expressed genes, and profile of expressed and unexpressed genes suggest that the overall expression profile of cultured cells is significantly different from native RPE. RPE cells grown on collagen IV, laminin, and fibronectin have profiles more similar than cells grown on plastic, Matrigel, or collagen I. The overall mRNA phenotype, however, is different from morphologically normal, native macular RPE. PMID:14982971

Tian, Jane; Ishibashi, Kazuki; Handa, James T

2004-04-13

359

Pathogenicity of Listeria monocytogenes grown on crabmeat.  

PubMed Central

The pathogenicity of Listeria monocytogenes as influenced by growth on crabmeat at 5 and 10 degrees C was studied. Crabmeat was inoculated with L. monocytogenes V7 (ca. 10(4) CFU/g) and incubated for up to 14 days at 5 and 10 degrees C. At selected incubation times, L. monocytogenes was removed from crabmeat by washing with 0.1 M potassium phosphate buffer (pH 7.0), and populations were determined by surface plating on LiCl-phenylethanol-moxalactam agar. Buffered suspensions were then centrifuged, and the resulting pellets were suspended in phosphate buffer containing 10% glycerol and stored at -18 degrees C. Thawed, diluted suspensions of cells were tested for pathogenicity by intraperitoneal injection into immunocompromised and nonimmunocompromised mice. L. monocytogenes cells recovered from crabmeat and then recultured in tryptose phosphate broth (TPB), as well as cells which had not been passed through crabmeat but had been cultured in TPB, were likewise harvested, suspended in buffered 10% glycerol, frozen, thawed, diluted, and tested for pathogenicity by intraperitoneal injection. Growth on crabmeat at 5 and 10 degrees C did not have a significant effect on pathogenicity. The population of L. monocytogenes necessary to kill about 50% of the immunocompromised mice in each test set within 7 days was about 10(4) CFU, and this result was not significantly affected by storage temperature of the crabmeat or type of substrate, i.e., crabmeat or TPB, on which it had grown.

Brackett, R E; Beuchat, L R

1990-01-01

360

Effects of Ammonia and Volatile Fatty Acids Produced by Oral Bacteria on Tissue Culture Cells  

Microsoft Academic Search

Culture filtrates of several bacterial species isolated from the oral cavity were tested for their effects on two types of tissue culture cells: Vero cells, the continuous cell line of African green monkey kidney cells; and chondrocytes, isolated from 15-day-old chick embryo tibiae. Only a limited number of bacterial species — i.e., the asaccharolytic black-pigmented Bacteroides species and Fusobacterium species

T. J. M. van Steenbergern; L. M. S. van der Mispel; J. de Graaff

1986-01-01

361

Comparative analysis of the lipids of Acinetobacter species grown on hexadecane.  

PubMed Central

A comparative analysis of the cellular and extracellular lipids of Acinetobacter species HO1-N indicated basic physiological differences in hexadecane-grown cells. The cellular lipids obtained from hexadecane-grown cells were characterized by 3- and 18-fold increases in the phospholipid fraction and the mono- and diglyceride fraction, respectively, over that obtained from nutrient broth-yeast extract-grown cells. The cellular-associated pools of hexadecane were shown to comprise approximately 8% of the dry cell weight of hexadecane-grown cells. The extracellular lipids obtained from the culture broths of hexadecane-grown cells were comprised of triglyceride, mono- and diglyceride, free fatty acid, and wax ester. These lipids were either absent or present in minor concentrations in the culture broths of nutrient broth-yeast extract-grown cells. The exponential growth of Acinetobacter sp. on hexadecane was characterized by the significant accumulation of free fatty acid, monoglyceride, and diglyceride in the culture medium. Wax ester was shown to represent a minor portion of the extracellular lipids during the exponential growth phase, appearing in significant proportion only after the culture had entered the stationary phase of growth.

Makula, R A; Lockwood, P J; Finnerty, W R

1975-01-01

362

Diverse apoptotic pathways in enterovirus 71-infected cells  

Microsoft Academic Search

Mechanisms related to the neuropathogenesis of enterovirus 71 infection remain unclear. This investigation conducts a comprehensive\\u000a study of the apoptotic pathways in neural and non-neural cells following enterovirus 71 infection. Infections with enterovirus\\u000a 71 not only induce classical cytopathic effects in SF268 (human glioblastoma), SK-N-MC (human neuroblastoma), RD, and Vero\\u000a cells, but also induce classic signs of apoptosis in all

Shih-Cheng Chang; Jing-Yi Lin; Lily Yen-Cheng Lo; Mei-Ling Li; Shin-Ru Shih

2004-01-01

363

Vesicular Stomatitis Virus Maturation Sites in Six Different Host Cells  

Microsoft Academic Search

SUMMARY Six different cell types, L, Vero, HeLa, BHKzI, PK(H13) and CF, were infected with vesicular stomatitis virus. A minimum of IOO individual virus-containing cells of each type was scored for the sites of viral maturation as observed by electron microscopy of thin sections. The principal site of viral maturation was the intra- cytoplasmic vacuolar membranes for PK(H13) and the

Y. C. Zee; A. J. Hackett; L. Talens

1970-01-01

364

Altered interaction of the matrix protein with the cytoplasmic tail of hemagglutinin modulates measles virus growth by affecting virus assembly and cell-cell fusion.  

PubMed

Clinical isolates of measles virus (MV) use signaling lymphocyte activation molecule (SLAM) as a cellular receptor, whereas vaccine and laboratory strains may utilize the ubiquitously expressed CD46 as an additional receptor. MVs also infect, albeit inefficiently, SLAM(-) cells, via a SLAM- and CD46-independent pathway. Our previous study with recombinant chimeric viruses revealed that not only the receptor-binding hemagglutinin (H) but also the matrix (M) protein of the Edmonston vaccine strain can confer on an MV clinical isolate the ability to grow well in SLAM(-) Vero cells. Two substitutions (P64S and E89K) in the M protein which are present in many vaccine strains were found to be responsible for the efficient growth of recombinant virus in Vero cells. Here we show that the P64S and E89K substitutions allow a strong interaction of the M protein with the cytoplasmic tail of the H protein, thereby enhancing the assembly of infectious particles in Vero cells. These substitutions, however, are not necessarily advantageous for MVs, as they inhibit SLAM-dependent cell-cell fusion, thus reducing virus growth in SLAM(+) B-lymphoblastoid B95a cells. When the cytoplasmic tail of the H protein is deleted, a virus with an M protein possessing the P64S and E89K substitutions no longer grows well in Vero cells yet causes cell-cell fusion and replicates efficiently in B95a cells. These results reveal a novel mechanism of adaptation and attenuation of MV in which the altered interaction of the M protein with the cytoplasmic tail of the H protein modulates MV growth in different cell types. PMID:17442724

Tahara, Maino; Takeda, Makoto; Yanagi, Yusuke

2007-04-18

365

Pullulan production by Aureobasidium pullulans grown on ethanol stillage as a nitrogen source.  

PubMed

Pullulan production by Aureobasidium pullulans strain RP-1 using thin stillage from fuel ethanol production as a nitrogen source was studied in a medium using corn syrup as a carbon source. The use of 1% thin stillage as a nitrogen source instead of ammonium sulphate elevated polysaccharide production by strain RP-1 cells when grown on a concentration of up to 7.5% corn syrup, independent of yeast extract supplementation. Dry weights of cells grown in medium containing ammonium sulphate as the nitrogen source were higher than the stillage-grown cells after 7 days of growth. The viscosity of the polysaccharide on day 7 was higher for cells grown on thin stillage rather than ammonium sulphate as a nitrogen source. The pullulan content of the polysaccharide elaborated by ammonium sulphate-grown cells on day 7 was higher than the pullulan content of polysaccharide produced by stillage-grown cells regardless of whether yeast extract was added to the culture medium. PMID:9121381

West, T P; Strohfus, B

1996-01-01

366

Variations of two pools of glycogen and carbohydrate in Saccharomyces cerevisiae grown with various ethanol concentrations.  

PubMed

Glycogen, a major reservoir of energy in Saccharomyces cerevisiae, is found to be present as soluble and membrane-bound insoluble pools. Yeast cells can store excess glycogen when grown in media with higher concentration of sugar or when subjected to nutritional stress conditions. Saccharomyces cerevisiae NCIM-3300 was grown in media having ethanol concentrations up to 12% (v/v). The effects of externally added ethanol on glycogen and other carbohydrate content of yeast were studied by using alkali digestion process. Fermentative activities of cells grown in the presence of various ethanol concentrations (2-8% v/v) exhibited increase in values of glycogen and other carbohydrate, whereas cells grown with higher concentrations of ethanol (10-12% v/v) exhibited depletion in glycogen and carbohydrate content along with decrease in cell weight. Such inhibitory effect of ethanol was also exhibited in terms of reduction in total cell count of yeast grown in media with 2-16% (v/v) ethanol and 8% (w/v) sugar. These data suggest that, as the plasma membrane is a prime target for ethanol action, membrane-bound insoluble glycogen might play a protective role in combating ethanol stress. Elevated level of cell-surface alpha-glucans in yeast grown with ethanol, as measured by using amyloglucosidase treatment, confirms the correlation between ethanol and glycogen. PMID:20373126

Dake, M S; Jadhv, J P; Patil, N B

2010-04-07

367

Carbonic anhydrase activity in acetate grown Methanosarcina barkeri  

Microsoft Academic Search

Cell extracts (27000xg supernatant) of acetate grown Methanosarcina barkeri were found to have carbonic anhydrase activity (0.41 U\\/mg protein), which was lost upon heating or incubation with proteinase K. The activity was inhibited by Diamox (apparent Ki=0.5 mM), by azide (apparent Ki=1 mM), and by cyanide (apparent Ki=0.02 mM). These and other properties indicate that the archaebacterium contains the enzyme

Marion Karrasch; Michael Bott; Rudolf K. Thauer

1989-01-01

368

Performance of six cell lines in the suspension-infection test used for the detection of herpes simplex virus  

Microsoft Academic Search

Six cell lines were assessed in the suspension-infection (SI) test for suitability for the rapid culture of herpes simplex virus (HSV). For the SI test, the specimen was combined in growth medium with trypsinized, suspended culture cells before allowing the cells to settle into a monolayer growth pattern. The cells tested in the SI assay were MV1-Lu, vero, C1008, BSC-1,

Teresa Rich; F. Brent Johnson

1998-01-01

369

Cell culture adaptation of Puumala hantavirus changes the infectivity for its natural reservoir, Clethrionomys glareolus, and leads to accumulation of mutants with altered genomic RNA S segment.  

PubMed Central

This paper reports the establishment of a model for hantavirus host adaptation. Wild-type (wt) (bank vole-passaged) and Vero E6 cell-cultured variants of Puumala virus strain Kazan were analyzed for their virologic and genetic properties. The wt variant was well adapted for reproduction in bank voles but not in cell culture, while the Vero E6 strains replicated to much higher efficiency in cell culture but did not reproducibly infect bank voles. Comparison of the consensus sequences of the respective viral genomes revealed no differences in the coding region of the S gene. However, the noncoding regions of the S gene were found to be different at positions 26 and 1577. In one additional and independent adaptation experiment, all analyzed cDNA clones from the Vero E6-adapted variant were found to carry substitutions at position 1580 of the S segment, just 3 nucleotides downstream of the mutation observed in the first adaptation. No differences were found in the consensus sequences of the entire M segments from the wt and the Vero E6-adapted variants. The results indicated different impacts of the S and the M genomic segments for the adaptation process and selective advantages for the variants that carried altered noncoding sequences of the S segment. We conclude that the isolation in cell culture resulted in a phenotypically and genotypically altered hantavirus.

Lundkvist, A; Cheng, Y; Sjolander, K B; Niklasson, B; Vaheri, A; Plyusnin, A

1997-01-01

370

A Novel Cell-Based Method to Detect Shiga Toxin 2 from Escherichia coli O157:H7 and Inhibitors of Toxin Activity  

Technology Transfer Automated Retrieval System (TEKTRAN)

Escherichia coli O157:H7 is a leading cause of foodborne illness. This human pathogen produces Shiga toxins (Stx1 and Stx2) which inhibit protein synthesis by inactivating ribosome function. The present study describes a novel cell-based assay to detect Stxs and inhibitors of Stx activity. A Vero...

371

Listeria monocytogenes grown at 7° C shows reduced acid survival and an altered transcriptional response to acid shock compared to L. monocytogenes grown at 37° C.  

PubMed

Survival of the food-borne pathogen Listeria monocytogenes in acidic environments (e.g., in the human stomach) is vital to its transmission. Refrigerated, ready-to-eat foods have been sources of listeriosis outbreaks. The purpose of this study was to determine whether growth at a low temperature (i.e., 7°C) affects L. monocytogenes survival or gene transcription after exposure to a simulated gastric environment (i.e., acid shock at 37°C). L. monocytogenes cells grown at 7°C were less resistant to artificial gastric fluid (AGF) or acidified brain heart infusion broth (ABHI) than bacteria grown at higher temperatures (i.e., 30°C or 37°C). For L. monocytogenes grown at 7°C, stationary-phase cells were more resistant to ABHI than log-phase cells, indicating that both temperature and growth phase affect acid survival. Microarray transcriptomic analysis revealed that the number and functional categories of genes differentially expressed after acid shock differed according to both growth temperature and growth phase. The acid response of L. monocytogenes grown to log phase at 37°C involved stress-related transcriptional regulators (i.e., ?(B), ?(H), CtsR, and HrcA), some of which have been implicated in adaptation to the intracellular environment. In contrast, for bacteria grown at 7°C to stationary phase, acid exposure did not result in differential expression of the stress regulons examined. However, two large operons encoding bacteriophage-like proteins were induced, suggesting lysogenic prophage induction. The adaptive transcriptional response observed in 37°C-grown cells was largely absent in 7°C-grown cells, suggesting that temperatures commonly encountered during food storage and distribution affect the ability of L. monocytogenes to survive gastric passage and ultimately cause disease. PMID:22447604

Ivy, R A; Wiedmann, M; Boor, K J

2012-03-23

372

Rapid detection of respiratory syncytial virus and influenza A virus in cell cultures by immunoperoxidase staining with monoclonal antibodies.  

PubMed

Peroxidase-labeled monoclonal antibodies against respiratory syncytial virus (RSV) and influenza A virus were used for immunoperoxidase staining (IPS) of cell cultures inoculated with nasopharyngeal aspirates. Cells were grown in 24-well plates, and specimens were inoculated by low-speed centrifugation. Cultures were incubated for 2 days at 37 degrees C and then fixed, stained, and observed by light microscopy. IPS was compared with standard virus isolation by using cultures of human diploid fibroblasts and Vero, HEp-2, and HeLa cell lines for RSV and Madin-Darby canine kidney cells for influenza A virus; these cultures were inoculated with specimens that were previously stored at -70 degrees C. Of 40 known RSV-positive specimens, 30 were found to be positive on reinoculation by both methods, and an additional 5 specimens were found to be positive by IPS only. Of 190 specimens tested for influenza A virus, 14 were positive by IPS and in tubes, and a further 8 specimens were positive by IPS only. IPS was also compared with direct detection of viral antigens in nasopharyngeal aspirates by a time-resolved fluoroimmunoassay (TR-FIA). Fresh nasopharyngeal aspirates were inoculated into human diploid fibroblasts and Madin-Darby canine kidney cells and tested for RSV and influenza A virus, respectively, by IPS. Of 110 specimens tested for RSV, 37 were positive in total, 32 were positive by IPS, and 33 were positive by TR-FIA. Of 150 specimens tested for influenza A virus, 39 were positive in total, 35 were positive by IPS, and 34 were positive by TR-FIA. IPS of cultures inoculated by centrifugation and incubated for 2 days is a sensitive method for the diagnosis of respiratory virus infections, and 24-well plates allow for the easy processing of a large number of specimens. PMID:2199488

Waris, M; Ziegler, T; Kivivirta, M; Ruuskanen, O

1990-06-01

373

Influence of osmolarity on lipopolysaccharides and virulence of Aeromonas hydrophila serotype O:34 strains grown at 37 degrees C.  

PubMed Central

Growth of Aeromonas hydrophila serotype O:34 strains at 37 degrees C at low and high osmolarity resulted in changes in the lipopolysaccharide (LPS) and virulence of the strains tested. We previously described the effect of growth temperature on LPS and virulence of these strains (S. Merino et al., Infect. Immun. 60:4343-4349, 1992). The effect of osmolarity can be observed when the cells grow at 37 degrees C but not when they grow at 20 degrees C. Purified LPS from cells cultivated at 37 degrees C and high osmolarity was smooth, while the LPS extracted from the cells cultivated at low osmolarity was rough. Furthermore, the strains were more virulent for fish and mice when they were grown at high osmolarity than when they were grown at low osmolarity and also showed increased extracellular activities when they were grown at high osmolarity. Finally, cells grown at high osmolarity showed better adhesion to HEp-2 cells than the same cells grown at low osmolarity, and furthermore the cells grown at high osmolarity were resistant to the bactericidal activity of nonimmune serum, while the same cells grown at low osmolarity were sensitive.

Aguilar, A; Merino, S; Rubires, X; Tomas, J M

1997-01-01

374

Phorbol ester induces the rapid processing of cell surface heparin-binding EGF-like growth factor: conversion from juxtacrine to paracrine growth factor activity.  

PubMed Central

Vero cell heparin-binding epidermal growth factor-like growth factor (HB-EGF) is synthesized as a 20- to 30-kDa membrane-anchored HB-EGF precursor (proHB-EGF). Localization and processing of proHB-EGF, both constitutive and 12-O-tetradecanoylphorbol 13-acetate (TPA)-inducible, was examined in Vero cells overexpressing recombinant HB-EGF (Vero H cells). Flow cytometry and fluorescence immunostaining demonstrated that Vero cell proHB-EGF is cell surface-associated and localized at the interface of cell to cell contact. Cell surface biotinylation and immunoprecipitation detected a 20- to 30-kDa heterogeneous proHB-EGF species. Vero H cell surface proHB-EGF turned over constitutively with a half-life of 1.5 h. Some of the 20- to 30-kDa cell surface-associated proHB-EGF was processed and a 14-kDa species of bioactive HB-EGF was released slowly, but most of the proHB-EGF was internalized, displaying a diffuse immunofluorescent staining pattern and accumulation of proHB-EGF in endosomes. Addition of TPA induced a rapid processing of proHB-EGF at a Pro148-Val149 site with a half-life of 7min. The TPA effect was abrogated by the protein kinase C inhibitors, staurosporine and H7. Kinetic analysis showed that loss of cell surface proHB-EGF is maximal at 30 min after addition of TPA and that proHB-EGF is resynthesized and the initial cell surface levels are regained within 12-24 h. Loss of cell surface proHB-EGF was concomitant with appearance of 14- and 19-kDa soluble HB-EGF species in conditioned medium. Vero H cell-associated proHB-EGF is a juxtacrine growth factor for EP170.7 cells in coculture. Processing of proHB-EGF resulted in loss of juxtacrine activity and a simultaneous increase in soluble HB-EGF paracrine mitogenic activity. It was concluded that processing regulates HB-EGF bioactivity by converting it from a cell-surface juxtacrine growth factor to a processed, released soluble paracrine growth factor. Images

Goishi, K; Higashiyama, S; Klagsbrun, M; Nakano, N; Umata, T; Ishikawa, M; Mekada, E; Taniguchi, N

1995-01-01

375

MBE grown iron-based nanostructures  

NASA Astrophysics Data System (ADS)

Interest in magnetic nanostructures has increased rapidly because of their potential applications in a number of magnetic nanotechnologies such as high-density magnetic recording media, magnetic field sensors, magnetic nanoprobes for spin-polarized microscopy and cell manipulation in biomedical technology. Successful incorporation of ferromagnetic nanostructures in semiconductors may open a new area in spintronic applications. In this study, two kinds of Fe-based nanostructures were grown by the molecular beam epitaxy (MBE) technique, namely, Fe quantum dots (QDs) and Fe nanowires (NWs). For Fe QDs, a multilayer magnetic QD sample containing 5 layers of Fe QDs embedded in 6 layers of ZnS spacer was grown on a GaP(100) substrate. High resolution transmission electron microscopy (HRTEM) observations reveal that the Fe QDs are single crystalline with spherical shape of diameters around 3 to 4 nm and area density of 1.5 x 1012 cm-2 . Its zero-field cooled (ZFC) and field cooled (FC) curves measured at low field (100 Oe) show the magnetic relaxation effect with a blocking temperature around 26 K. The hysteresis loop measured at 5 K shows a coercivity of 83 Oe, confirming the slow relaxation process and coercivity enhancement attributed to the nanoparticle nature of the sample. To study the transport property of Fe QDs, a Au/ZnS/Fe-QDs/ZnS/n+-GaAs Schottky-barrier structure containing 5 layers of Fe QDs was fabricated on a n+-GaAs(100) substrate. Its current-voltage (I-V) characteristics measured from 5 to 295 K display negative differential resistance (NDR) for temperature . 50 K, which is caused by the presence of Fe QDs. The highest peak-to-valley current ratio obtained at 5 K is as high as 15:1. Staircase-like I-V characteristic was also observed at low temperature in some devices fabricated from this structure. Possible mechanisms that can account for the observed unusual I-V characteristics in this structure were discussed. Two types of self-assembled Fe NWs were grown on ZnS/GaP(100) surface under high growth/annealing temperature. The Type-A Fe NWs orient along the ZnS[110] direction with irregular shape, while the type-B Fe NWs orient along either the ZnS[180] or [810] direction with seemingly straight shape. Detailed HRTEM and selected area diffraction (SAD) studies reveal that both types were single-crystalline with their elongated axis along the Fe<100> direction family possibly due to the fact that the easy axis of Fe is along this direction. We have proposed a mean-field model to explain the slight misalignment of the type-B Fe NWs. The I-V characteristic of a single type-B Fe NW measured at room temperature displays a straight line nature corresponding to a resistivity about 2.3 x 10-7Om.

Lok, Shu Kin

376

Nuclear factor of activated T-cells (NFAT) plays a role in SV40 infection  

SciTech Connect

Recent evidence highlighted a role for the transcription factor, nuclear factor of activated T-cells (NFAT), in the transcription of the human polyomavirus JCV. Here we show that NFAT is also important in the transcriptional control of the related polyomavirus, Simian Virus 40 (SV40). Inhibition of NFAT activity reduced SV40 infection of Vero, 293A, and HeLa cells, and this block occurred at the stage of viral transcription. Both NFAT3 and NFAT4 bound to the SV40 promoter through {kappa}B sites located within the 72 bp repeated enhancer region. In Vero cells, NFAT was involved in late transcription, but in HeLa and 293A cells both early and late viral transcription required NFAT activity. SV40 large T-Ag was found to increase NFAT activity and provided a positive feedback loop to transactivate the SV40 promoter.

Manley, Kate [Graduate Program in Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02912 (United States); O'Hara, Bethany A. [Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02912 (United States); Atwood, Walter J. [Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI 02912 (United States)], E-mail: Walter_Atwood@Brown.edu

2008-03-01

377

Is cell death induced by nematocysts extract of medusa pelagia noctiluca related to oxidative stress?  

PubMed

Pelagia noctiluca, a jellyfish widely distributed in the Mediterranean waters, especially in coastal areas of Tunisia, has garnered attention because of its stinging capacity and the resulting public health hazard. Crude extracts of P. noctiluca nematocysts have been tested for their cytotoxicity on Vero cells. Our results clearly showed that nematocysts induced cell mortality in a dose- and time-dependent manner. A cytoprotective effect against cell mortality was obtained when Vero cells were treated with Vitamin E. This process was further confirmed by the generation of reactive oxygen species (ROS) and the induction of Hsp 70 and 27 protein expressions. Thus, our findings suggested that oxidative stress is involved in the toxicity of pelagia nematocysts and may therefore constitute the major mechanism of this medusa nematocysts toxicity. © 2011 Wiley Periodicals, Inc. Environ Toxicol 28: 498-506, 2013. PMID:21809431

Ayed, Yosra; Chayma, Bouaziz; Hayla, Abassi; Abid, Salwa; Bacha, Hassen

2011-08-01

378

Effect of high salinity on tracheary element differentiation in light-grown callus of Mesembryanthemum crystallinum  

Microsoft Academic Search

This study investigated the inhibitory effects of NaCl on tracheary element (TE) differentiation in light-grown callus of\\u000a ice plant Mesembryanthemum crystallinum L., a halophyte which adaptes well to saline environments. When ice plant callus was grown in a modified Linsmaier-Bednar\\u000a and Skoog culture medium containing no NaCl (control medium), up to 20% of ice plant cells differentiated into tracheary elements

Hungchen Emilie Yen; Shi-Kae Yen

1999-01-01

379

Variations of two pools of glycogen and carbohydrate in Saccharomyces cerevisiae grown with various ethanol concentrations  

Microsoft Academic Search

Glycogen, a major reservoir of energy in Saccharomyces cerevisiae, is found to be present as soluble and membrane-bound insoluble pools. Yeast cells can store excess glycogen when grown in\\u000a media with higher concentration of sugar or when subjected to nutritional stress conditions. Saccharomyces cerevisiae NCIM-3300 was grown in media having ethanol concentrations up to 12% (v\\/v). The effects of externally

M. S. Dake; J. P. Jadhv; N. B. Patil

2010-01-01

380

Application of cell culture enrichment for improving the sensitivity of mycoplasma detection methods based on nucleic acid amplification technology (NAT)  

Microsoft Academic Search

Herein, we present data demonstrating that the application of initial cell culture enrichment could significantly improve\\u000a mycoplasma testing methods based on the nucleic acid amplification technology (NAT) including a polymerase chain reaction\\u000a (PCR)\\/microarray method. The results of the study using Vero cells demonstrated that this cell culture is able (1) to support\\u000a efficient growth of mycoplasmas of primary interest, i.e.,

Hyesuk Kong; Dmitriy V. Volokhov; Joseph George; Pranvera Ikonomi; Donna Chandler; Christine Anderson; Vladimir Chizhikov

2007-01-01

381

The U L13 Protein Kinase and the Infected Cell Type Are Determinants of Posttranslational Modification of ICP0  

Microsoft Academic Search

The herpes simplex virus infected-cell protein 0 (ICP0) acts as a promiscuous transactivator of genes introduced into eukaryotic cells by transfection or infection. The protein is highly posttranslationally modified by phosphorylation and nucleotidylylation. We have examined the electrophoretic mobility and phosphorylation of ICP0 in Vero and rabbit skin cells infected with wild-type virus or viruses from which the UL13 gene

William O. Ogle; Teresa I. Ng; Kara L. Carter; Bernard Roizman

1997-01-01

382

NUTRITION OF CONTAINER-GROWN CHRISTMAS CACTI  

Microsoft Academic Search

The effect of nitrogen (N), phosphorus (P), potassium (K) and lime additions to container-grown Schlumbergera x buckleyi were examined in two experiments. In each case rooted cuttings were grown in peat\\/perlite (1:1, v\\/v), with three plants per pot, for 17 months in a heated greenhouse. Foliage growth and flowering were strongly enhanced by added N and fertilization of between 1800

M. I. Spurway; M. B. Thomas

2001-01-01

383

Polymorphs of Rubrene Crystal Grown from Solution  

NASA Astrophysics Data System (ADS)

Single crystals of rubrene were grown by slow cooling of solutions in various solvents. Hexagonal single crystals were obtained from p-xylene, whereas parallelogram-shaped crystals were grown from aniline. Both types of crystal were obtained from propan-1-ol. Single-crystal X-ray diffraction analyses showed that the hexagonal and parallelogram-shaped crystals belonged to the orthorhombic system and the triclinic system, respectively. The triclinic crystals showed much poorer carrier mobilities than did the orthorhombic crystals.

Matsukawa, Takeshi; Yoshimura, Masashi; Uchiyama, Masahito; Yamagishi, Masakazu; Nakao, Akiko; Takahashi, Yoshinori; Takeya, Junichi; Kitaoka, Yasuo; Mori, Yusuke; Sasaki, Takatomo

2010-08-01

384

A Simple Serum-free Freezing Medium for Serum-free Cultured Cells  

Microsoft Academic Search

Because the presence of serum in cell culture raises safety problems for the production of biologicals, we have developed a serum-free medium (SFM) for the cryopreservation of animal cells. This medium is based on the SFM MDSS2, to which 10% dimethylsulfoxide (DMSO) and 0·1% methylcellulose or 3% polyvinyl pyrrolidone or no other additive than DMSO were added. Both, Vero and

O.-W. Merten; S. Petres; E. Couvé

1995-01-01

385

Clonogenic Assay of Type A Influenza Viruses Reveals Noninfectious Cell-Killing (Apoptosis-Inducing) Particles  

Microsoft Academic Search

Clonogenic (single-cell plating) assays were used to define and quantify subpopulations of two genetically closely related variants of influenza virus A\\/TK\\/OR\\/71 that differed primarily in the size of the NS1 gene product; they expressed a full-size (amino acids (aa) 1 to 230) or truncated (aa 1 to 124) NS1 protein. Monolayers of Vero cells were infected with different amounts of

John M. Ngunjiri; Margaret J. Sekellick; Philip I. Marcus

2008-01-01

386

Adaptation to cell culture induces functional differences in measles virus proteins  

Microsoft Academic Search

BACKGROUND: Live, attenuated measles virus (MeV) vaccine strains were generated by adaptation to cell culture. The genetic basis for the attenuation of the vaccine strains is unknown. We previously reported that adaptation of a pathogenic, wild-type MeV to Vero cells or primary chicken embryo fibroblasts (CEFs) resulted in a loss of pathogenicity in rhesus macaques. The CEF-adapted virus (D-CEF) contained

Bettina Bankamp; Judith M Fontana; William J Bellini; Paul A Rota

2008-01-01

387

Investigation of the Cytotoxicity of Antimicrobial Peptide P40 on Eukaryotic Cells  

Microsoft Academic Search

The in vitro cytotoxicity of the antimicrobial peptide P40 was investigated. The food grade bacteriocin nisin was also analyzed\\u000a for comparison. VERO cells were treated with different concentrations (0.02–2.5 ?g ml?1) of nisin and P40, and cell viability and plasma membrane integrity were checked by MTT, neutral red uptake (NRU), and lactate\\u000a dehydrogenase (LDH) assays. In MTT and NRU assays the EC50

Rodrigo A. Vaucher; Mario L. Teixeira; Adriano Brandelli

2010-01-01

388

Generation of influenza vaccine viruses on Vero cells by reverse genetics: an H5N1 candidate vaccine strain produced under a quality system  

Microsoft Academic Search

Human influenza vaccine reference strains are prepared as required when an antigenically new strain is recommended by WHO for inclusion in the vaccine. Currently, for influenza A, these strains are produced by a double infection of embryonated hens’ eggs using the recommended strain and the laboratory strain PR8 which grows to high titre in eggs, in order to produce a

Carolyn Nicolson; Diane Major; John M. Wood; James S. Robertson

2005-01-01

389

Dermacentor marginatus and Ixodes ricinus ticks versus L929 and Vero cell lines in Rickettsia slovaca life cycle evaluated by quantitative real time PCR  

Microsoft Academic Search

Ticks transmit many different pathogens to animals, humans and their pets. Rickettsia slovaca, as a member of the spotted-fever-group rickettsiae is an agent of the human disease Tick-borne lymphadenopathy (TIBOLA),\\u000a also called Dermacentor-borne necrosis erythema and lymphadenopathy (DEBONEL), which occurs from the Mediterranean to central Europe, transmitted\\u000a by Dermacentor reticulatus and Dermacentor marginatus (Acari: Ixodidae). In this study, quantitative real

Vojtech Boldiš; Eva Špitalská

2010-01-01

390

Enhanced capacity of DNA repair in human cytomegalovirus-infected cells  

SciTech Connect

Plaque formation in Vero cells by UV-irradiated herpes simplex virus was enhanced by infection with human cytomegalovirus (HCMV), UV irradiation, or treatment with methylmethanesulfonate. Preinfection of Vero cells with HCMV enhanced reactivation of UV-irradiated herpes simplex virus more significantly than did treatment with UV or methylmethanesulfonate alone. A similar enhancement by HCMV was observed in human embryonic fibroblasts, but not in xeroderma pigmentosum (XP12BE) cells. It was also found that HCMV infection enhanced hydroxyurea-resistant DNA synthesis induced by UV light or methylmethanesulfonate. Alkaline sucrose gradient sedimentation analysis revealed an enhanced rate of synthesis of all size classes of DNA in UV-irradiated HCMV-infected Vero cells. However, HCMV infection did not induce repairable lesions in cellular DNA and did not significantly inhibit host cell DNA synthesis, unlike UV or methylmethanesulfonate. These results indicate that HCMV enhanced DNA repair capacity in the host cells without producing detectable lesions in cellular DNA and without inhibiting DNA synthesis. This repair appeared to be error proof for UV-damaged herpes simplex virus DNA when tested with herpes simplex virus thymidine kinase-negative mutants.

Nishiyama, Y.; Rapp, F.

1981-04-01

391

DEGENERATION AND REGENERATION OF CHLOROPLASTS IN EUGLENA GRACILIS GROWN IN THE PRESENCE OF ACETATE: ULTRASTRUCTURAL EVIDENCE  

Microsoft Academic Search

SUMMARY When green cells of Euglena gracilis, strain Z, were light-grown for several months on a solid medium containing an excess of sodium acetate (1-0% instead of the normal 01 %) , some 30% of the cells were colourless. The 'acetate-bleached' organisms, isolated by plating methods and subsequently incubated in the light in a liquid medium, regained the capacity to

GIAN LUIGI VANNINI

392

Consumption choices concerning the genetically engineered, organically grown, and traditionally grown foods: An experiment  

Microsoft Academic Search

While debate over the new agricultural biotechnology has been relatively muted, food may come under increased scrutiny when consumers confront new products. The American public may demand regulations such as labeling. To test the influence of defining\\/labeling products, an experiment gave subjects choices between organically and traditionally grown or between genetically engineered and traditionally grown food for lunch. Logistic regression

Patrick Stewart

2000-01-01

393

Nutritional studies with Pseudomonas aeruginosa grown on inorganic sulfur sources.  

PubMed Central

Pseudomonas aeruginosa was grown on a succinate-basal salts medium supplemented with various inorganic sulfur compounds as its sole source of sulfur. The organism was able to grow on the sodium salts of sulfide, thiosulfate, tetrathionate, dithionite, metabisulfite, sulfite, or sulfate, but not on those of dithionate. Analyses of the culture media after 24 h of growth indicated accumulation of sulfate from each inorganic sulfur source except sulfate. Manometric studies with resting cells obtained by growth on each of these sulfur sources yielded net oxygen uptake for all substrates except sulfite and dithionate. Similar results were obtained with extracts from these cells by spectrophotometric techniques. Thiosulfate oxidase activity appeared to be induced by growth on sulfide, thiosulfate, or tetrathionate, with little or no activity observed when cells were grown on inorganic sulfur sources of higher oxidative states. Metabisulfite oxidase appeared to be associated with growth on all inorganic sulfur compounds. Rhodanese activity appeared to be constitutively present, and its activity, observed only in soluble fraction, seemed independent of the growth medium employed. Thiosulfate and tetrathionate oxidase activities were studied in greater detail than some of the other sulfur oxidases, and both were found to be distributed between particulate and soluble fractions.

Schook, L B; Berk, R S

1978-01-01

394

Marine diatoms grown in chemostats under silicate or ammonium limitation. III. Cellular chemical composition and morphology of Chaetoceros debilis, Skeletonema costatum , and Thalassiosira gravida  

Microsoft Academic Search

Three marine diatoms, Skeletonema costatum, Chaetoceros debilis, and Thalassiosira gravida were grown under no limitation and ammonium or silicate limitation or starvation. Changes in cell morphology were documented with photomicrographs of ammonium and silicate-limited and non-limited cells, and correlated with observed changes in chemical composition. Cultures grown under silicate starvation or limitation showed an increase in particulate carbon, nitrogen and

P. J. Harrison; H. L. Conway; R. W. Holmes; C. O. Davis

1977-01-01

395

Wood quality from fast-grown plantations  

SciTech Connect

As forestry becomes more intensive and as forestry operations move toward the tropical areas, an increasing proportion of the wood available to the industry will come from young, fast-grown plantations. The wood of such trees, especially from the conifers, is so different that it will have a major effect on utilization and product standards. Acceptability of wood from fast-grown plantations will change as solid wood and paper quality standards change. Some of the primary effects on wood and products from fast-grown plantations are discussed in this paper. The wood is very suitable for some products and poor for others. The paper reports on conifers and hardwoods separately, with a large section on Eucalyptus.

Zobel, B.

1981-01-01

396

Inorganic nanostructures grown on graphene layers  

NASA Astrophysics Data System (ADS)

This article presents a review of current research activities on the hybrid heterostructures of inorganic nanostructures grown directly on graphene layers, which can be categorized primarily as zero-dimensional nanoparticles; one-dimensional nanorods, nanowires, and nanotubes; and two-dimensional nanowalls. For the hybrid structures, the nanostructures exhibit excellent material characteristics including high carrier mobility and radiative recombination rate as well as long-term stability while graphene films show good optical transparency, mechanical flexibility, and electrical conductivity. Accordingly, the versatile and fascinating properties of the nanostructures grown on graphene layers make it possible to fabricate high-performance optoelectronic and electronic devices even in transferable, flexible, or stretchable forms. Here, we review preparation methods and possible device applications of the hybrid structures consisting of various types of inorganic nanostructures grown on graphene layers.

Park, Won Il; Lee, Chul-Ho; Lee, Jung Min; Kim, Nam-Jung; Yi, Gyu-Chul

2011-09-01

397

Antibacterial effect of theaflavin, polyphenon 60 (Camellia sinensis) and Euphorbia hirta on Shigella spp.--a cell culture study.  

PubMed

Antibacterial effect of compounds extracted from Camellia sinensis L. and the methanol extract of Euphorbia hirta L. were studied against dysentery causing Shigella spp. using the Vero cell line. Cytotoxicity studies of the extracts were performed using the cell line and the non-cytotoxic concentration of the extract was tested for antibacterial activity against the cytopathic dose of the pathogen. These extracts were found to be non-cytotoxic and effective antibacterial agents. PMID:8847884

Vijaya, K; Ananthan, S; Nalini, R

1995-12-01

398

Inhibition of West Nile virus replication in cells stably transfected with vector-based shRNA expression system  

Microsoft Academic Search

In this study, the efficacies of short hairpin RNAs (shRNAs) targeting different regions of West Nile virus (WNV) strain Sarafend genome were investigated. Short hairpin RNAs targeting Capsid, NS2B and NS4B genes were cloned into pSilencer™ 3.1-H1 neo and designated as pshCapsid, pshNS2B and pshNS4B, respectively. Vero cells that were positively transfected were selected for creating stable cell lines expressing

S. P. Ong; J. J. H. Chu; M. L. Ng

2008-01-01

399

Mixed infections in vitro with different Chlamydiaceae strains and a cell culture adapted porcine epidemic diarrhea virus  

Microsoft Academic Search

Assuming a synergistic or additive effect of Chlamydiaceae in coexistence with other enteropathogenic agents, the viral\\/bacterial interaction between a cell culture adapted porcine epidemic diarrhea virus (ca-PEDV) and different Chlamydiaceae strains was studied in vitro. Vero cells were dually infected with ca-PEDV and one of the three chlamydial strains Chlamydia trachomatis S45, Chlamydophila abortus S26\\/3 or Chlamydophila pecorum 1710S. Three

Angela Stuedli; Paula Grest; Irene Schiller; Andreas Pospischil

2005-01-01

400

A comparison of fermentation in the cyanobacterium Microcystis PCC7806 grown under a light\\/dark cycle and continuous light  

Microsoft Academic Search

The cyanobacterium Microcystis PCC7806, grown under continuous light, fermented endogenously stored glycogen to equimolar amounts of acetate and ethanol when incubated anaerobically in the dark. In addition, H-2, CO2 and some L-lactate were produced. This fermentation pattern differed from that displayed by cells which had been grown under an alternating light\\/dark (16\\/8 h) cycle. Such cells produced much more ethanol

ROY MOEZELAAR; LUCAS J. STAL

1997-01-01

401

Catalysis of an isotopic exchange between CO 2 and the carboxyl group of acetate by Methanosarcina barkeri grown on acetate  

Microsoft Academic Search

Cell suspensions of Methanosarcina barkeri (strain Fusaro) grown on acetate were found to catalyze the formation of methane and CO2 from acetate (30–40 nmol\\/min·mg protein) and an isotopic exchange between the carboxyl group of acetate and 14CO2 (30–40 nmol\\/min·mg protein). An isotopic exchange between [14C]-formate and acetate was not observed. Cells grown on methanol mediated neither methane formation from acetate

Bernhard Eikmanns; Rudolf K. Thauer

1984-01-01

402

Oxidation Properties of Vapor Grown Graphite Fibers.  

National Technical Information Service (NTIS)

The oxidation behavior of a novel carbon fiber has been determined using a Thermogravimetric Analysis (TGA) technique in flowing air (52 ml/min) at temperatures ranging from 500 to 1100 C. The oxidation rates of three preparations of vapor grown carbon fi...

M. L. Lake R. Y. Lin J. K. Hickok K. K. Brito

1988-01-01

403

Melt-Grown Oxide-Metal Composites.  

National Technical Information Service (NTIS)

This research is designed to develop melt-grown oxide-metal composite structures for high field electron emission testing. A number of refractory oxide-metal mixtures (i.e. UO2-W, stabilized ZrO2 and HfO2-W, UO2-Ta, and the rare earth oxides of Gd2O3, Nd2...

A. T. Chapman J. F. Benzel J. K. Cochran R. K. Feeney F. W. Long

1973-01-01

404

Consumer Attitudes Toward Organically Grown Lettuce  

Microsoft Academic Search

This research shows that approximately 29 percent of lettuce purchasers in California expect to purchase an organically grown lettuce product in the future. Organic lettuce purchasers are more likely to be female, have a higher household income and a higher level of education. Consumers are concerned with the freshness, quality, price, and environmental impact of the lettuce they purchase. The

Marianne McGarry; Bradey Johnson Wolf; Kerry Cochran; Lynn Hamilton

405

Detection of some dengue-2 virus antigens in infected cells using immuno-microscopy  

Microsoft Academic Search

Summary Immunoelectron microscopy was used to detect the distribution of some dengue-2 virus proteins in infected Vero andAedes albopictus (C 6\\/36) cells. It was found that the envelope protein (GP 60) was located in clumps on the surface of plasma membrane, and accumulated very little in the infected cytoplasm. However no envelopment of dengue-2 virus nucleocapsids through the plasma membranes

Mah Lee Ng; Linda C. Corner

1989-01-01

406

The potency of acyclovir can be markedly different in different cell types  

Microsoft Academic Search

Acyclovir is an acyclic guanine analog with a considerable activity against herpes simplex viruses. We studied the antiherpetic activity of acyclovir in macrophages and fibroblast cell lines. Utilising a plaque reduction assay we found that acyclovir potently inhibited the HSV-1 replication in macrophages (EC50 = 0.0025 ?M) compared to Vero (EC50 = 8.5 ?M) and MRC-5 (EC50 = 3.3 ?M)

Giorgio Brandi; Giuditta F. Schiavano; Emanuela Balestra; Barbara Tavazzi; Carlo-Federico Perno; Mauro Magnani

2001-01-01

407

Strain Variation in Glycosaminoglycan Recognition Influences Cell-Type-Specific Binding by Lyme Disease Spirochetes  

Microsoft Academic Search

Lyme disease, a chronic multisystemic disorder that can affect the skin, heart, joints, and nervous system is caused by Borrelia burgdorferi sensu lato. Lyme disease spirochetes were previously shown to bind glycosamino- glycans (GAGs). In the current study, the GAG-binding properties of eight Lyme disease strains were deter- mined. Binding by two high-passage HB19 derivatives to Vero cells could not

NIKHAT PARVEEN; DOUGLAS ROBBINS; JOHN M. LEONG

1999-01-01

408

Catabolic enzymes of the acetogen Butyribacterium methylotrophicum grown on single-carbon substrates.  

PubMed Central

When grown on formate, formate-CO, and methanol-CO, Butyribacterium methylotrophicum contained high levels of tetrahydrofolate (H4folate) and required enzymes, carbon monoxide dehydrogenase, formate dehydrogenase, and hydrogenase. The activities of methylene-H4folate reductase were comparable to other H4 folate activities (which ranged from 0.55 to 9.28 mumol/min per mg of protein) when measured by an improved procedure. The H4folate activities in formate-grown cells were twice those found in formate-CO-grown cells. This result correlated with a growth yield on formate that was one-half that on formate-CO. The stoichiometry of the formyl-H4folate synthetase reaction was 1 mol of ATP per 1 mol of formate. The methylene-H4folate dehydrogenase was NAD+ dependent. We conclude that B. methylotrophicum utilizes these enzymes in homoacetogenic catabolism.

Kerby, R; Zeikus, J G

1987-01-01

409

Novel, anionic, antiviral septapeptides from mosquito cells also protect monkey cells against dengue virus.  

PubMed

We have shown previously that ultrafiltrates (5 kDa cutoff) of cell-free medium from mosquito cell cultures persistently infected with DENV serotype 2 (DENV-2) contained a novel antiviral agent (called viprolaxikine) that could protect pre-treated, naïve mosquito cells from DENV infection. Here, we show that viprolaxikine also reduced DENV-2 titers by almost 4 logs (>99.9%) when compared to Vero cells mock-treated with ultrafiltrates from cultures of uninfected mosquito cells. Protease treatment removed the anti-DENV-2 activity. Pre-incubation for 48-h was required to obtain the maximum, dose-dependent protection against DENV-2, indicating that the antiviral activity was based on the interaction between Vero cells and viprolaxikine rather than direct action of viprolaxikine on DENV-2. Activity was highest against DENV-2, but there was also significant activity against the 3 other DENV serotypes. LC-MS-MS analysis revealed that the active viprolaxikine fraction contained anionic, antiviral peptides, each comprised of 7 amino acids (DDHELQD, DETELQD and DEVMLQD or DEVLMQD) and with a common sequence motif of D-D/E-X-X-X-Q-D. These sequences do not occur in the dengue virus genome, suggesting that the peptides are produced by the host insect cells when persistently infected with DENV-2. These peptides represent a new class of anionic, insect-derived, antiviral peptides with activity against a flavivirus in both mammalian and insect cells. PMID:23603496

Laosutthipong, Chaowanee; Kanthong, Nipaporn; Flegel, Timothy W

2013-04-17

410

Novel Cell-Based Method To Detect Shiga Toxin 2 from Escherichia coli O157:H7 and Inhibitors of Toxin Activity  

Microsoft Academic Search

Escherichia coli O157:H7 is a leading cause of food-borne illness. This human pathogen produces Shiga toxins (Stx1 and Stx2) which inhibit protein synthesis by inactivating ribosome function. The present study describes a novel cell-based assay to detect Stx2 and inhibitors of toxin activity. A Vero cell line harboring a destabilized variant (half-life, 2 h) of the enhanced green fluorescent protein

Beatriz Quinones; Shane Massey; Mendel Friedman; Michelle S. Swimley; Ken Teter

2009-01-01

411

The Herpes Simplex Virus Type 1 Regulatory Protein ICP27 Is Required for the Prevention of Apoptosis in Infected Human Cells  

Microsoft Academic Search

The herpes simplex virus type 1 (HSV-1) ICP27 protein is an immediate-early or a protein which is essential for the optimal expression of late genes as well as the synthesis of viral DNA in cultures of Vero cells. Our specific goal was to characterize the replication of a virus incapable of synthesizing ICP27 in cultured human cells. We found that

MARTINE AUBERT; JOHN A. BLAHO

1999-01-01

412

Influence of Na on Cu(In,Ga)Se2 solar cells grown on polyimide substrates at low temperature: Impact on the Cu(In,Ga)Se2\\/Mo interface  

Microsoft Academic Search

There are still open questions regarding the nature of the positive effect of the presence of Na on the performance of Cu(In,Ga)Se2 based, chalcopyrite thin film solar cells, especially at low processing temperatures. Studying Cu(In,Ga)Se2 thin film devices fabricated from low-temperature coevaporated absorbers on polyimide substrates by admittance and J-V-T measurements, characteristic properties are identified for different amounts of Na

R. Caballero; C. A. Kaufmann; T. Eisenbarth; A. Grimm; I. Lauermann; T. Unold; R. Klenk; H. W. Schock

2010-01-01

413

Counting molecular-beam grown graphene layers  

NASA Astrophysics Data System (ADS)

We have used the ratio of the integrated intensity of graphene's Raman G peak to that of the silicon substrate's first-order optical phonon peak, accurately to determine the number of graphene layers across our molecular-beam (MB) grown graphene films. We find that these results agree well both, with those from our own exfoliated single and few-layer graphene flakes, and with the results of Koh et al. [ACS Nano 5, 269 (2011)]. We hence distinguish regions of single-, bi-, tri-, four-layer, etc., graphene, consecutively, as we scan coarsely across our MB-grown graphene. This is the first, but crucial, step to being able to grow, by such molecular-beam-techniques, a specified number of large-area graphene layers, to order.

Plaut, Annette S.; Wurstbauer, Ulrich; Pinczuk, Aron; Garcia, Jorge M.; Pfeiffer, Loren N.

2013-06-01

414

Production of buffalo embryos using oocytes from in vitro grown preantral follicles.  

PubMed

The present study examines the use of buffalo preantral follicles as a source of oocytes for in vitro embryo production. Preantral follicles were isolated from abattoir-derived buffalo ovaries and were grown for 100 days in five different culture systems: (1) minimum essential medium (MEM); (2) coconut water; (3) MEM + ovarian mesenchymal cell (OMC) co-culture; (4) MEM + granulosa cell (GC) co-culture; or (5) MEM + cumulus cell (CC) co-culture. Low growth rates for the preantral follicles were observed when follicles were cultured in MEM or coconut water medium. Moderate growth rates were seen for OMC and GC co-cultures, and high rates of growth were observed when follicles were grown in CC co-culture. The survival of preantral follicles was low in the MEM culture (<25%), but was over 75% in the other culture systems. Oocytes were not recovered from the MEM group, while an oocyte recovery rate of 80-100% was observed when the follicles were cultured with coconut water/somatic cells. Transferable embryos could be produced only with the oocytes obtained from preantral follicles grown in the OMC and CC co-culture systems. This study demonstrates, for the first time, that it is possible to produce buffalo embryos by in vitro fertilization of oocytes derived from in vitro grown preantral follicles. PMID:18221582

Gupta, P S P; Ramesh, H S; Manjunatha, B M; Nandi, S; Ravindra, J P

2008-02-01

415

Cytochemical localization of catalase activity in methanol-grown Hansenula polymorpha  

Microsoft Academic Search

The localization of peroxidase activity in methanol-grown cells of the yeast Hansenula polymorpha has been studied by a method based on cytochemical staining with diaminobenzidine (DAB). The oxidation product of DAB occurred in microbodies, which characteristically develop during growth on methanol, and in the intracristate space of the mitochondria.

J. P. van Dijken; M. Veenhuis; C. A. Vermeulen; W. Harder

1975-01-01

416

The incorporation of erbium into molecular beam epitaxy grown gallium arsenide  

Microsoft Academic Search

Erbium-doped gallium arsenide has been grown by molecular beam epitaxy under varying growth conditions and analysed by secondary ion mass spectrometry. The concentration of erbium incorporated into the gallium arsenide lattice for a given effusion cell temperature has been found to vary considerably with the V : III (As : Ga) flux ratio. Higher levels of erbium incorporation occur when

P. Rutter; K. E. Singer; A. R. Peaker

1997-01-01

417

Carbon Nanocapsules Grown on Carbon Fibers  

NASA Astrophysics Data System (ADS)

Carbon nanocapsules grown on pitch-based carbon fibers were investigated by high-resolution electron microscopy. It was found that they were formed during heating up to 2000° C in 1 atm N2 gas. Two types of nanocapsules were found: one was a capsule enclosing a CaS single crystal and the other was a cubic hollow capsule. The growth mechanism of these carbon nanocapsules was discussed by comparing the structures of particles formed at several temperatures.

Kusunoki, Michiko; Ikuhara, Yuichi; Kon, Jun-ichi

1995-03-01