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1

Response of anther culture in vitro to irradiation of spike and culturing with Al stress in barley  

International Nuclear Information System (INIS)

Spikes of two barley lines treated with 60Co ?-radiation as anther culture materials, the callus induction and green plant regeneration were investigated on the media containing Al. The results showed that the frequency of callus induction was dramatically decreased by irradiation treatment and green plant regeneration was failed at a dose of 10 Gy. The calli was obtained from anthers cultured with Al-medium, and also green plants were regenerated even in higher Al concentration. The frequency of callus induction was reduced in culturing with higher stress of Al, and the green plant regeneration was also decreased. (authors)

2

A survey on the response of some wheat genotypes to haploid production through anther culture system  

International Nuclear Information System (INIS)

An experiment was carried out to investigate the response of five Iranian wheat cultivars (Tajan, Atila, Mahooti, red Bafghi and white Bafghi) and four segregating F 3 wheat lines compared to a tester genotype in another culture system for the purpose of haploid production. Anthers were planted in p 4 induction medium. Cold and gamma radiation pretreatments were also applied to study the stimulating effect on call i/plant lets production. Conventional growth conditions in the green house were not met du c to lack of mean; of controlling day temperature. None of the cultivars were produced call i in p 4 induction medium. The segregating F 3 lines increasing percentages of call i production belonged to lines 2044, 2208, and 2005, respectively. Cold pretreatment showed positive stimulating effect on call i production only in lines 2005, and 2097. The combined pretreatments of segregating lines before being plated in the induction medium had a significant effect in calc production regarding line 2005. In case of line 2044, however, only the gamma radiation dose of 2 Gy combined with the cold pretreatment was true. Line 2097 showed no positive effect of simulation in call i production because of the combined pretreatments. The highest plant let production percentage belonged to line 2005 and followed by lines 2208, and 2044. Considering that the conventional growth conditions for donor plants were not met in the greenhouse, the response to haploid production of wheat genotponse to haploid production of wheat genotypes used in this experiment can not necessarily be true. The optimum donor plant growth conditions is one the principal conditions for obtaining satisfactory results from another culture system to be used in the breeding scheme

3

Response of different genotypes of wheat, rice and black beans to anther, embryo and other tissue cultures  

International Nuclear Information System (INIS)

The objective of the basic studies we have been conducting in our laboratory is to establish callus induction and in vitro plant regeneration protocols starting with several tissues of Guatemalan varieties of wheat (Triticum aesticum L.), rice (Oryza sativa L.) and especially black bean (Phaseolus vulgaris L.) in order to obtain disease resistance, earliness, and dwarf plants. Wheat anthers and immature embryos of varieties Patzun, Comalapa, Chocoyo, and Xequijel cultured in N6, Potato II, and MS basal media supplemented with auxin and cytokinin gave the best responses in callus induction and plant regeneration. Anthers and mature embryos of indica rice varieties Precozicta and Virginai, when cultured in MS, B5, N6, and Potato II basal media with different hormonal combinations gave a good response in callus induction. However, a satisfactory response in plant regeneration was not obtained. With black beans, when hypocotyls and mature embryos of black bean varieties Quinack Che and Parramos were cultured in MS basal medium supplemented with different concentrations of NAA and kinetin, more than 60% callus induction was produced. When Quinack Che calli were transferred to MS basal medium supplemented with 1 mg/l NAA plus 0.5 mg/l BAP, green points of regeneration were visible in these calli. (author). 34 refs, 28 tabs

4

Evaluation of effect of different gamma ray doses on anther culture response in two Iranian wheat landraces  

International Nuclear Information System (INIS)

Wheat according to its importance as a source of food is the most important strategic agricultural product and has the highest level of under planting lands around the world. Double haploid induction methods are able to raise wheat breeding efficiency through decreasing length of breeding programming and increasing selection efficacy. In this experiment for determining the effect of gamma radiation of seeds on anther culture response of wheat, two recalcitrant Iranian wheat landraces, Graecum and Nigricum with no response to anther culture were chosen. Callus induction and plant regeneration traits from anther culture of these landraces and twenty of their random selected mutant genotypes which were produced through seed radiation with 100, 150, 200, 250Gy of gamma ray doses were evaluated. A factorial design based on completely randomized design with five replication was used to compare callus induction and plant regeneration percents of genotypes. Gamma ray doses levels and genotypes were two factors of this experiment which had a significant effect on both of callus induction and plant regeneration traits. An evaluation of the means revealed that the highest level of callus induction is noticed in 200Gy (12.5%) and that of plant induction is noticed in 150Gy (67.28%). the highest mean of callus induction (68.6%) was obtained in genotype L9.200.2 as a mutant of Nigricum landrace and The highest mean of plant induction (93.12%) was obtained in genotype L8.150.1 as a %) was obtained in genotype L8.150.1 as a mutant of Graecum landrace. (author)

5

Regeneration of Eggplant Through Anther Culture  

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The study was conducted to develop a protocol for anther culture of eggplant. Six eggplant cultivars viz., Dohazari, IPM 31, Laffa S, Ishurdi L, ISD-006 and Jessore L were implanted on MS medium with different hormone supplements viz., 2 mg L-1 NAA + 2 mg L-1 BAP, 1 mg L-1 IAA + 2 mg L-1 BAP and 2 mg L-1 2, 4-D + 2 mg L-1 BAP for callus induction. The highest survivability of anthers (35 %) and the highest percentage of callus ...

Khatun, F.; Meah, M. B.; Nasiruddin, K. M.

2006-01-01

6

Attempts to induce haploids in anther cultures of sugar, fodder and wild species of beet  

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Full Text Available In the present investigation, aimed at obtaining beet haploids from anthers, the effect of mineral media, potato and sugar beet extract and p-fluorophenylalanine (PFP in combination with growth substances was tested. Nutrient-starved plants as anther-donors, anther-starvation, cold treatment and photoperiod were also analysed. On all mineral media the anthers produced callus and roots; however, the percentage depended on the combination of growth substances used. The best medium for differentiation was that of Linsmaier and Skoog with 25 µM zeatin or 6-(3-methyl-2-butenylaminopurine with 5 µM naphthalene-l-acetic acid (25.5%. The addition of PFP caused an increase in the percentage of anther differentiation (41.6%. Besides callus and roots on one of the anthers (in ca. 140000 tested, vegetative buds were formed from which numerous plants were obtained (2n. Plant and anther nutrient starvation did not improve the anther response to differentiation, nor did it induce haploid development, similarly as cold treatment of inflorescences or isolated anthers. The anthers of wild species showed lower ability to differentiate than those of sugar or fodder beets. Cytological analyses showed formation of multicellular structures until ca. the 12-th day of anther culture; afterwards, they degenerated.

Janina Rogozi?ska

1982-03-01

7

Induction of haploid morphogenic calluses from in vitro cultured anthers  

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Apricot (Prunus armeniaca) ‘Harcot’ anthers were cultured in vitro for the production of haploid plants. The best androgenic response was achieved with Nitsch and Nitsch (1969) medium, supplemented with 4.52 microM 2,4-D, 4.52 micoM zeatin, 2.85 microM IAA and 40 g l?1 sucrose. Cultures were maintained in the dark for 8 days, at 28 ?C, followed by transfer to a 16-h photoperiod, with 35 micro mm?2 s?1 light intensity and 24/22 ?C day/night temperature. The androgenic response wa...

Peixe, Augusto; Barroso, Joa?o; Potes, Amely; Pais, Maria

2004-01-01

8

Meiosis of anther culture regenerants in asparagus (Asparagus officinalis L.)  

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Pollen mother cells obtained from regenerated plants of asparagus (Asparagus officinalis L.), in a population composed exclusively of male plants, through the process of anther culture from the hybrid G27 X 22-8, were analyzed during meiosis. It was observed that, during theprocess of anther culture by organogenesis, the pollen mother cells of the regenerants had great genomic instability, as evidenced by disturbances in all the meiotic phases of the first and second division. Furthermore, st...

Galli Leonardo; Viégas Judith; Augustin Eliane; Eckert Marcia Ines; Silva João Baptista da

1998-01-01

9

The Direct Regeneration of Maize Haploids Through Anther Culture  

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The genetics of plants regenerated from anther-derived callus was investigated using single crosses & inbreds of maize. Anther culture in maize (Zea mays L.) usually follows an indirect procedure involving callus induction and differentiation on at least two different media. Alternatively, development of a direct procedure by which plantlets can be regenerated directly on one medium seems desirable, if acceptable frequency of plant regeneration could be obtained and an effective pr...

Hassan, L.; Ahmad, S. D.; Okumus, A.

2001-01-01

10

Combined effect of induced mutations and media for improving genetic architecture of brassica through anther culture  

International Nuclear Information System (INIS)

Radiation and media effect on the anther culture response of two brassica napus varieties (i.e. Pak cheen and Salam) were studied. It was observed that low doses of gamma radiation (100-250 rads) enhanced the anther callusing response of the varieties on both of the cultured media. Different genotypic response was observed in case of plant regeneration. In variety Salam Plant lets were regenerated from the calli treated up to the dose of 750 rads. However, in case of variety Pak-cheen the calli could not be differentiated beyond 100 rads. (author)

11

Meiosis of anther culture regenerants in asparagus (Asparagus officinalis L.  

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Full Text Available Pollen mother cells obtained from regenerated plants of asparagus (Asparagus officinalis L., in a population composed exclusively of male plants, through the process of anther culture from the hybrid G27 X 22-8, were analyzed during meiosis. It was observed that, during theprocess of anther culture by organogenesis, the pollen mother cells of the regenerants had great genomic instability, as evidenced by disturbances in all the meiotic phases of the first and second division. Furthermore, structural chromosomal abnormalities, in addition to aneuploidy and polyploidy, were observed.

Galli Leonardo

1998-01-01

12

Effect of the genotype and gamma irradiation on the anther cultures of a 10x10 diallel cross of wheat  

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Anther culture responsiveness, irradiation effect and reciprocal effect were evaluated on ten genotypes (V1-V10) and a 101x0 diallel cross. Gamma irradiation dose of 100 Gy was applied to seeds of parents and F1 cross from which the donor plants were grown. Non-irradiated donor plants were also used for comparison. Anthers were plated on potato-2 callus induction medium and calli formed were transferred to MS medium supplemented with sucrose (3%), indolacetic acid (1.0 mg/L), kinetin (1.0 mg/L), inositol (100 mg/L) and solidified with agar (0.7%). Genotypes showed big differences for callus induction, plant regeneration and anther culturability rate. The most responsive materials were V2, V10 and V5 with 76.0, 27.4 and 10.8 green plants per 100 anthers respectively. No irradiation effect was found for the parents nor the F1 crosses on the pooled data. Mean anther culture response of specific genotypes showed that irradiation significantly increased anther culturability rate of V3 from 0.1 to 27.6 green plants per 100 anthers. No reciprocal effect was observed. (author)

13

The Direct Regeneration of Maize Haploids Through Anther Culture  

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Full Text Available The genetics of plants regenerated from anther-derived callus was investigated using single crosses & inbreds of maize. Anther culture in maize (Zea mays L. usually follows an indirect procedure involving callus induction and differentiation on at least two different media. Alternatively, development of a direct procedure by which plantlets can be regenerated directly on one medium seems desirable, if acceptable frequency of plant regeneration could be obtained and an effective procedure of chromosome doubling of regenerated plantlets is available. Yupie (YP and N6 were used as basal media and 10 growth regulators (2,4-D, kinetin, NAA, IAA, IBA, dicamba, pCPA, 6-BA, 2ip and hypoxanthine were tested to evaluate the feasibility of direct regeneration of haploid plantlets of eight single cross hybrids and four inbred lines. The results indicated that the direct generation of plantlets is feasible through anther culture, though it is genotype and medium dependent. Ten plantlets were regenerated directly from single cross hybrid M60 X M96. The more effective medium was N6 basal medium plus 2,4-D (2.0 mg l-1 and kinetin (1.5 mg l-1. Regeneration frequency (percent of anthers producing plantlets ranged from 1 to 4%.

L. Hassan

2001-01-01

14

Evaluation of androgenic competence through anther culture in common eggplant and related species  

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Anther culture is a convenient technique to obtain androgenic haploid and doubled haploid (DH) plants. In common eggplant (Solanum melongena), this technique has been used to develop DH pure lines for producing uniform F1 hybrid seed of some commercial varieties. However, a comprehensive study of the variation of this useful trait among different materials of common eggplant and related species is still lacking. In this work, we studied the androgenic response of 12 accessions of common eggpl...

Pablo; Prohens Toma?s, Jaime; Segui?-simarro, Jose? M.; Salas Aragon, Pablo

2011-01-01

15

Adapting rice anther culture to gene transformation and RNA interference.  

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Anther culture offers a rapid method of generating homozygous lines for breeding program and genetic analysis. To produce homozygous transgenic lines of rice (Oryza sativa L.) in one step, we developed an efficient protocol of anther-callus-based transformation mediated by Agrobacterium after optimizing several factors influencing efficient transformation, including callus induction and Agrobacterium density for co-cultivation. Using this protocol, we obtained 145 independent green transformants from five cultivars of japonica rice by transformation with a binary vector pCXK1301 bearing the rice gene, Xa21 for resistance to bacterial blight, of which 140 were further confirmed by PCR and Southern hybridization analysis, including haploids (32.1%), diploids (62.1%) and mixoploids (7.5%). Fifteen diploids were found to be doubled haploids, which accounted for 10.7% of the total positive lines. Finally, by including 28 from colchicine induced or spontaneous diploidization of haploids later after transformation, a total of 43 doubled haploids (30.7%) of Xa21 transgenic lines were obtained. We also generated two RNAi transgenic haploids of the rice OsMADS2 gene, a putative redundant gene of OsMADS4 based on their sequence similarity, to investigate its possible roles in rice flower development by this method. Flowers from the two OsMADS2 RNAi transgenic haploids displayed obvious homeotic alternations, in which lodicules were transformed into palea/lemma-like tissues, whereas identities of other floral organs were maintained. The phenotypic alternations were proved to result from specific transcriptional suppression of OsMADS2 gene by the introduced RNAi transgene. The results confirmed that OsMADS2 is involved in lodicule development of rice flower and functionally redundant with OsMADS4 gene. Our results demonstrated that rice anther culture could be adapted to gene transformation and RNAi analysis in rice. PMID:17172048

Chen, Caiyan; Xiao, Han; Zhang, Wenli; Wang, Aiju; Xia, Zhihui; Li, Xiaobing; Zhai, Wenxue; Cheng, Zhukuan; Zhu, Lihuang

2006-10-01

16

Meiosis of anther culture regenerants in asparagus (Asparagus officinalis L.)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Foi analisada a meiose em células mãe de pólen de plantas de aspargo (Asparagus officinalis L.) de uma população composta exclusivamente de plantas masculinas, obtidas através do processo de cultura de anteras do híbrido G27 X 22-8. Foi observado que, durante o processo de cultura de anteras, via ca [...] logênese, as células mãe de pólen dos regenerantes apresentaram grande instabilidade genômica, evidenciada por irregularidades nas fases de diacinese, assim como de metáfase, anáfase, telófase da primeira e segunda divisão meiótica. Além disto, o processo originou anormalidades cromossômicas estruturais em adição às aneuploidias e poliploidias. Abstract in english Pollen mother cells obtained from regenerated plants of asparagus (Asparagus officinalis L.), in a population composed exclusively of male plants, through the process of anther culture from the hybrid G27 X 22-8, were analyzed during meiosis. It was observed that, during theprocess of anther culture [...] by organogenesis, the pollen mother cells of the regenerants had great genomic instability, as evidenced by disturbances in all the meiotic phases of the first and second division. Furthermore, structural chromosomal abnormalities, in addition to aneuploidy and polyploidy, were observed.

Leonardo, Galli; Judith, Viégas; Eliane, Augustin; Marcia Ines, Eckert; João Baptista da, Silva.

1998-03-01

17

Cucumber mosaic virus resistant mutant from tobacco's anthers treated with ? ray through anther culture  

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Flower buds of Nicotiana tabacum cv. K326, NC89 and 8611, in which the microspore is in the phase of single nucleus and the nucleus is on the side, were irradiated with 60Co ?-ray. Plant lets from anther culture were transplanted and inoculated with poisonous fluid of CMV. The results showed that there was an orientation relation between the variation of disease resistance of plants of NC89, 8611 and the dose of 60Co ?-ray. The variation of leaves of plants was analogous to symptom of CMV when the dose was equal to or more than 4, which caused difficulty for selection. When dose was less than 2krad, there was no difference in disease resistance between the plants induced from irradiation of 60Co ?-ray and the control. However, when dose was equal to 2krad, the difference of disease resistance was at the level of significance. CMV-resistant mutants were selected from the population of haploid plant of NC89 and 8611 induced by 2.0 krad of 60Co ? ray

18

Radiation effect in anther cultures of rice variety Krispo-38  

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Seeds of rice variety Krispo-38 were irradiated with 0, 100, 200, 300 and 400 Gy and sown in the greenhouse. Anthers from plants of each treatment containing uninucleate pollen grains were collected and cultured on an N6 agar medium with 5% sucrose concentration and supplemented with 3 mg/l NAA, 1 mg/l kinetin and 1 mg/l 2,4-D. The pollen grains were induced to develop calli. The proportion of anthers that produced calli varied from 0.8% for the 400 Gy treatment to 3.3% for the control. The calli were transferred to N6 medium with 3% sucrose concentration and supplemented with 0.5 mg/l NAA and 1 mg/l kinetin. The proportion of calli that produced green plants varied from 1.9% for the 300 Gy treatment to 10.5% for the 200 Gy one. Plants developed in 2-5 weeks, 101 plants were obtained. (author). 7 refs, 1 tab

19

Additives Promote Adventitious Buds Induction from Anther Culture of Bitter Melon (Momordica charantia L.  

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Full Text Available The effects of growth regulators, Thidiazuron (TDZ, silver nitrate (AgNO3, triacontanol and glutaminate on adventitious buds induction from anther culture of bitter melon (Momordica charantia L. were investigated. It was found that triacontanol was advantageous for buds development and adventitious buds differentiated from anther culture of bitter melon first time. On medium supplemented with glutaminate 0.1 mg L-1, protuberant structures differentiated on the surface of callus. AgNO3 and TDZ has no significant effect on promoting adventitious buds formation from anther culture of bitter melon.

Qian Luo

2012-01-01

20

The Influence of Genotype and Induction Medium on Efficiency of Anther Culture of Hetrotic Indica × Indica Rice Hybrids  

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Full Text Available This study was set up in the research station of Rice Research Institute of Iran (RRII to determine the response of three hetrotic Indica × Indica rice hybrids (Bahar1, IR75221H and IR69688H to anther culture on four induction media (N6, modified N6, chu and modified chu. To evaluate hybrids, the percentage of calluses which had been made from anthers in early uni- to mid- uninucleate stage and the number of regenerated plantlets of calluses in those media were determined. The results indicated that genotype, composition of callus induction medium and their interactions significantly affected callus percentage, total plant regeneration and production of green and albino plants. IR75221H hybrid was considerably superior for callus induction (1/64% and Bahar1 hybrid was the most desirable for producing of green plants (3/43% and total regeneration (12/24%. IR75221H hybrid produced higher albino plant (10/66% and IR69688H hybrid produced lower albino plant (6/45%. The best medium culture in the case of callus induction was modified N6 (2% and total regeneration (21/82% produced green plant (5/6%, and albino plant (16/22% was modified Chu among all media culture. However, genotypes showed different results in each media culture, and responses to hybrid of anther culture was low, but by changing the media culture we increased the response of culture.

A Ebadi

2009-04-01

 
 
 
 
21

Combining Ability and Heritability of Callus Induction and Green-Plant Regeneration in Rice Anther Culture  

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This study was conducted to determine the inheritance of callus induction and plant regeneration in rice anther culture. Low efficiencies of callus induction and green-plant regeneration have limited the application of anther culture in plant breeding programs. Four parents along with six F1 genotypes derived from a four-parent incomplete diallel mating set of two commercial lines (Amol2 and Amol3) and two local cultivars (Ghasroddashti and Rashti) were evaluated for their callus i...

Bagheri, N.; Jelodar, N. B.

2008-01-01

22

Regeneration of plants from anther, callus and protoplast cultures of rice (Oryza sativa L.)  

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The work described in this thesis focuses on the development of fully reproducible systems of plant regeneration through embryogenic callus and totipotent protoplast cultures of rice (Oryza sativa L. cv. Taipei 309). The calli originated from different explants, including excised anthers, isolated microspores, mature seed-embryos, immature seed-embryos and leaf-base meristems. In the callus culture and plant regeneration studies, excised anther-derived callus produced higher numbers of green ...

Nahar, Maksuda Anjuman

1994-01-01

23

Pretreatment Stress Enhances Embryogenic Callus Production in Anther Culture of Sturt’s Desert Pea (Swainsona formosa)  

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The aims of the experiment were to investigate the effect of pretreatment stress on the proliferation of anther-derived embryogenic callus, and its subsequent embryo regeneration in Swainsona formosa. Anthers were pretreated in starvation medium at cold (4 oC) temperature and cultured. Cultures were initially placed in darkness for four weeks, followed by 16-h photoperiod at 25 + 1 oC. The stress pretreatment was found to enhance embryogenic callus formation on cultured anthers. Further, soma...

ZULKARNAIN

2007-01-01

24

Improvement of rice anther culture and application of the technique in mutation breeding  

International Nuclear Information System (INIS)

The ability of callus formation and green plant regeneration was very different for different rice type and varieties in anther culture. The differentiation and regeneration of green plants were obviously improved when the rice anthers at about 30 d after culture on induction medium were irradiated with 20 Gy of ?-rays and calli were cultured on the differentiation medium containing 30 mg/L colchicines. The stimulation effect of ?-irradiation combined with colchicines was much better than that of their single use. Mutation frequency and selective efficiency in M2 were obviously increased by application of the technique

25

The early ontogeny of embryoids and callus from pollen and subsequent organogenesis in anther cultures of Datura metel and rice.  

Science.gov (United States)

Haploidy induction through anther culture has been examined in Datura metel and rice with a view to tracing the precise sequence of development of the pollen, either directly or through an intervening callus, into an embryo and seedling. In D. metel, the vegetative cell of the young pollen grain assumes the major role in formation of embryos whereas the generative cell and its few derivatives degenerate. Embryos and seedlings arising directly from pollen without an intervening callus phase always proved to be haploids, whereas those differentiating from pollen-derived callus gave haploid, diploid and even triploid plants. Cytological analysis of callus tissue showed cells of various ploidy levels ranging from haploid to triploid, and in rare instances even with higher chromosome numbers.In rice anther cultures the embryoids arose from an initial callus phase. Of 15 different rice cultivars tried, only four produced a callus, and in only one, was there differentiation of plants, both haploid and diploid ones. Among other species tried, egg plant has also yielded plantlets through a callus phase whereas only callus production has been achieved in jute, tea and petunia. No response has been obtained in wheat, maize, cotton and coconut.Coconut milk (CM) appears to be the most important component of the medium for the initial induction of embryoids and callus in anther cultures of most of the species tried. However, further growth and differentiation of plants may require a simpler medium; in D. metel, continued culture on CM led to dedifferntiation. PMID:24481698

Iyer, R D; Raina, S K

1972-06-01

26

In vitro Regeneration of Four Ethiopian Varieties of Sesame (Sesamum indicum L. using Anther Culture  

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Full Text Available The study aimed at developing a suitable and reproducible protocol of in vitro regeneration of haploid sesame (Sesamum indicum L. plantlets using anther culture. Anthers of four Ethiopian varieties, namely: Hirhir, Humera-1, Setit-1 and Non-Shatter were cultured in vitro to study their regenerating ability. Murashige and Skoog (MS media supplemented with different concentrations and combinations of plant growth regulators (PGRs were used. The highest callusing (56.20% and callus weight (8.33 g were observed in Hirhir cultured in MS medium supplemented with 2,4-D (2,4 dichlorophenoxyacetic acid at 2.0 mg L-1 + BAP (benzylaminopurine at 1.0 mg L-1. Shooting response was studied using green/friable calli of the varieties cultured in MS medium supplemented with BAP at the concentrations of 0.5, 1.0, 1.5 and 2.0 mg L-1 + NAA (naphthalene acetic acid at 1.0 mg L-1. Calli of Hirhir cultured in MS medium supplemented with BAP at 2.0 mg L-1 + NAA at 1.0 mg L-1 were the best in terms of percentage shooting and number of days to shooting. Non-Shatter showed the weakest response to the same treatment. Rooting of shoots was studied with 0, 0.25, 0.5, 0.75 and 1.0 mg L-1 of IBA + 0.5 mg L-1 of NAA. In this case too, whereas Hirhir cultured in MS medium supplemented with 0.25 mg L-1 IBA (indole-3-butyric acid +0.5 mg L-1 NAA showed the best response –87.15% in mean rooting, 11.66 mm in mean root length and 17.80 in mean days to rooting; Non-Shatter cultured in the same medium yield weakest response. Acclimatization responses of rooted in vitro seedlings were studied in coco peat and soil medium (comprising sand, cow dung and garden soil at a ratio of 2:1:1. Seedlings of Hirhir planted in both media gave better survival rate than that of the other varieties. The survival rates of Hirhir planted in coco peat and soil media were 66.7 and 50.0%, respectively.

M. Yifter

2013-01-01

27

Production of haploids from anther culture of banana [Musa balbisiana (BB)].  

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We report here, for the first time, the production of haploid plants of banana Musa balbisiana (BB). Callus was induced from anthers in which the majority of the microspores were at the uninucleate stage. The frequency of callus induction was 77%. Callus proliferation usually preceded embryo formation. About 8% of the anthers developed androgenic embryos. Of the 147 plantlets obtained, 41 were haploids (n=x=11). The frequency of haploid production depended on genotypes used: 18 haploid plants were produced from genotype Pisang klutuk, 12 from Pisang batu, seven from Pisang klutuk wulung and four from Tani. The frequency of regeneration was 1.1%, which was based on the total number of anthers cultured. Diploid plants (2n=2x=22) were also observed in the regenerated plants. The haploid banana plants that were developed will be important material for the improvement of banana through breeding programmes. PMID:12789424

Assani, A; Bakry, F; Kerbellec, F; Haïcour, R; Wenzel, G; Foroughi-Wehr, B

2003-02-01

28

A Comparison between Wheat and Maize Cross and Anther Culture Method for Production of Wheat Haploid Plants  

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The significance of haploid plants as genetic and plant breeding tools has been recognized for a long time. Haploid production techniques including anther culture, isolated microspore culture and intergeneric hybridization between wheat × Hordeum bulbosum and wheat × maize have been used to produce homozygous lines which accelerate breeding programs. In this study, wheat × maize hybridization and anther culture techniques were used for haploid production in six wheat genotypes. The results...

Ghobadi, C.; Sayed-tabatabaei, B. E.; Mahmoodi-ghehsareh, T.; Mirlohi, A.

2004-01-01

29

A Comparison between Wheat and Maize Cross and Anther Culture Method for Production of Wheat Haploid Plants  

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Full Text Available The significance of haploid plants as genetic and plant breeding tools has been recognized for a long time. Haploid production techniques including anther culture, isolated microspore culture and intergeneric hybridization between wheat × Hordeum bulbosum and wheat × maize have been used to produce homozygous lines which accelerate breeding programs. In this study, wheat × maize hybridization and anther culture techniques were used for haploid production in six wheat genotypes. The results showed that 70.7% of regenerated plants through anther culture were albino plants and only 29.2 % were green, while the plants produced through wheat × maize method were all green. Ploidy variation was not observed in plants regenerated through wheat × maize hybridization. It was concluded that wheat × maize crosses would be an appropriate and practical method for haploid production in different wheat genotypes, which in comparison with the anther culture method has a higher efficiency.

C. Ghobadi

2004-10-01

30

Additives Promote Adventitious Buds Induction from Anther Culture of Bitter Melon (Momordica charantia L.)  

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The effects of growth regulators, Thidiazuron (TDZ), silver nitrate (AgNO3), triacontanol and glutaminate on adventitious buds induction from anther culture of bitter melon (Momordica charantia L.) were investigated. It was found that triacontanol was advantageous for buds development and adventitious buds differentiated from anther culture of bitter melon first time. On medium supplemented with glutaminate 0.1 mg L-1, protuberant structures differentiated on the ...

Qian Luo; Jia Lai; Zesheng Yan; Huanxiu Li; Yi Tang; Li Zhang

2012-01-01

31

Plant regeneration from sorghum anther cultures and field evaluation of progeny.  

Science.gov (United States)

Embryogenic calli were obtained from a hybrid line of Sorghum bicolor (L.) Moench anthers with mid to late uninucleate pollen cultured in N6 medium supplemented with 3.0% sucrose, 2.0 mg/1 2,4-D, 0.8% agar and incubated at 30°C, which was the optimum temperature. The regeneration of embryos was obtained from the embryogenic calli cultured in modified MS medium supplemented with 3.0% sucrose, 2.0 mg/1 BAP combined with 0.3 mg/1 IAA and 0.8% agar. A total of 248 doubled haploids and 12 haploid plants were regenerated. In a subsequent field study, the selfed progeny from anther culture (designated as the anther culture-2, [A2] generation) derived families was compared with both the F2 and the F1 for agronomic and morphological traits. Significant differences were noticed between the family means of both A2 and F2 for all the quantitative traits studied. The distinctive difference in the behavior of the A2 families in comparison with the F2 was established by within family variance, which was significant in F2 for days to 50 per cent flowering, plant height, panicle length, leaf area index, dry matter production, harvest index and grain yield and was non-significant in A2. Male sterility, one of the potentially important traits, currently exploited in the hybrid seed production of cereals, including CSH5 hybrid sorghum and the morphological traits (panicle shape, compactness, grain color, glume color and nature of the leaf sheath) segregated in the F2. Such segregation was not observed within A2 families and they bred true to their respective A1 plants, indicating the rapid attainment of homozygosity/uniformity. The present study establishes the gametophytic origin of anther culture derived families and indicates the possibility of rapid production of homozygous lines which can be used as recombinant inbreds. PMID:24193766

Kumaravadivel, N; Sree Rangasamy, S R

1994-02-01

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Calli Induction through Anther Culture in Peach-Tomato Plants (Solanum sessiliflorum Dunal  

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Full Text Available Flower buds from peach tomato plants (Solanum sessiliflorum were collected to the establishment of a protocol of calli induction from anthers culture. Aseptic cultures were achieved after the immersion of explants into 70% ethanol for 45 sec followed by 0.8% sodium hypochlorite for 5 min. Cultivated anthers developed 50 and 70% of calli with 0.1 mg L-1 indole-3-acetic acid (IAA+5 mg L-1 kinetin (KIN and 0.1 mg L-1 indole-3-acetic acid (IAA+10 mg L-1 kinetin (KIN, respectively. The calli oxidation increased in treatments free of activated charcoal, daily pre-refrigeration (4°C for 48 h and 20 mg L-1 of kinetin (KIN. The best plant growth regulator concentration for stimulating calli formation was 5 mg L-1 of kinetin (KIN.

I. Romani

2009-01-01

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Evaluation of Effective Factors in Anther Culture of Iranian Rice (Oryza sativa L.) Cultivars  

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This study was conducted to develop the breeding method of anther culture for pure line induction in Iranian Rice cultivars. Several aspects were studied: the genotype factors, the culture medium, the date of sampling and the kind and content of sugar in culture medium. Results showed that the first date of sampling (middle July)had better callus induction than the second one and has led to increased callus induction of cultivars to 8.1 percent. In the investigation of carbon source, callus i...

Ghanbari, Ali; Babaeian-jelodar, Nadali; Bagheri, Nadali

2009-01-01

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Combining Ability and Heritability of Callus Induction and Green-Plant Regeneration in Rice Anther Culture  

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Full Text Available This study was conducted to determine the inheritance of callus induction and plant regeneration in rice anther culture. Low efficiencies of callus induction and green-plant regeneration have limited the application of anther culture in plant breeding programs. Four parents along with six F1 genotypes derived from a four-parent incomplete diallel mating set of two commercial lines (Amol2 and Amol3 and two local cultivars (Ghasroddashti and Rashti were evaluated for their callus induction and plant regeneration abilities. The results showed that the callus induction, green-plant regeneration and the effects of genotype and genotypexmedium interaction were significant (p<0.01. The local cultivars generally had a higher percent callus induction, plant regeneration and number of calli producing green plants than the commercial lines. The parents showed significant difference in anther callus formation, from 4.01% (Amol2 to 22.26% (Rashti. Combining ability analysis demonstrated the predominance of additive gene effects in the control of both characters with the local cultivars having higher combining ability for green-plant regeneration. Also gene action to be partially dominant for both characters. Combining ability analysis revealed that both additive and dominant gene effects are important in controlling callus induction and green-plant regeneration in rice.

N. Bagheri

2008-01-01

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The haploid embryoids development in anther culture of transformed tobacco (Nicotiana tabacum L.  

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Full Text Available Induction of pollen embryogenesis was used for the test of cytokinin influence on the development of pollen grain. Gene for maize cytokinin-specific ?-glucosidase were introduced into tobacco genome together with the methotrexate resistance marker (Brzobohatý et al. 1994. Anther culture of T1 generation of transformed Nicotiana tabacum L. plants revealed that high activity of ?-glucosidase caused a reduced regeneration of pollen embryoids. The stages of pollen embryoid development were comparable with those of zygotic embryos. Optimal nutritive medium contained charcoal and chelated iron. The absence of iron in the initiation medium caused a distinct decrease of pollen embryoid regeneration.

Jaroslava Dubová

1996-06-01

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Pretreatment Stress Enhances Embryogenic Callus Production in Anther Culture of Sturt’s Desert Pea (Swainsona formosa  

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Full Text Available The aims of the experiment were to investigate the effect of pretreatment stress on the proliferation of anther-derived embryogenic callus, and its subsequent embryo regeneration in Swainsona formosa. Anthers were pretreated in starvation medium at cold (4 oC temperature and cultured. Cultures were initially placed in darkness for four weeks, followed by 16-h photoperiod at 25 + 1 oC. The stress pretreatment was found to enhance embryogenic callus formation on cultured anthers. Further, somatic embryos were successfully regenerated from embryogenic callus upon transferred onto regeneration medium supplemented with 1% sucrose and 4.63 ?M kinetin, and later plantlets were obtained. Meanwhile, nonembryogenic callus continued to grow resulting in more callus mass without showing any embryoid initiation.

ZULKARNAIN

2007-03-01

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In vitro Plant Regeneration Through Anther Culture of Some Iranian Local Rice (Oryza sativa L. Cultivars  

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Full Text Available In this study, effect of different genotypes, different callus induction and regeneration media were investigated using seven Iranian local rice. Anthers were cultured on N6, Fj and L8 media containing the same hormonal combination 3 mg L-1 NAA, 0.5 mg L-1 Kn and 0.5 mg L-1 2, 4-D and incubated at 25± 1° C in dark for callus induction. All varieties in L8 medium, five varieties in Fj medium and six varieties in N6 medium produced highest percentage of callus. Calli induced in different induction media were transferred to SK 11 and N 19 medium and incubated at 25± 1° C in light for plantlet regeneration. Among seven varieties upon transfer to SK 11 medium, highest percentage (40% of green plants were produced in Hassani and in N 19 medium the highest percentage (15.78 of green plants and albino plants (21.05 were produced in Anbarbo. The finding in the present investigation showed that the successfully emberyogenesis and green plant regeneration in rice anther culture dependent on medium culture components and are affected by the genetic mack-up of the plants.

Reza Talebi

2007-01-01

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Attempts to induce haploids in anther cultures of sugar, fodder and wild species of beet  

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In the present investigation, aimed at obtaining beet haploids from anthers, the effect of mineral media, potato and sugar beet extract and p-fluorophenylalanine (PFP) in combination with growth substances was tested. Nutrient-starved plants as anther-donors, anther-starvation, cold treatment and photoperiod were also analysed. On all mineral media the anthers produced callus and roots; however, the percentage depended on the combination of growth substances used. The best medium for differen...

Janina Rogozi?ska; Maria Go?ka

1982-01-01

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Stimulation effects of ?-irradiation combined with colchicine on callus formation and green plant regeneration in rice anther culture  

International Nuclear Information System (INIS)

The ability of callus formation and green plant regeneration was very different for various rice types and varieties in rice anther culture. It was quite effective that rice anthers were irradiated with 10-40 Gy of ?-rays after 30 d incubation on induction medium and calli were treated on differentiation medium contained 10-75 mg/L of colchicine for increase of callus formation and green plant regeneration. Among these treatments, 10 Gy of ?-rats was the best for callus formation, and 20 Gy of ?-rays or 30 mg/L of colchicine was the most favourable for green plant regeneration. The simulation effect of 20 Gy of ?-irradiation combined with 30 mg/L of colchicine on green plant regeneration was much better than that of their separate use in rice anther culture

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Effects of gamma irradiation and other factors on the induction of calli and regeneration of greed plants in rice anther culture  

International Nuclear Information System (INIS)

Induction of calli and regeneration of green plantlets in anther culture of rice variety, Taipei 309, were greatly affected by gamma irradiation and other factors. Callus formation from the anthers of mid-uninucleate stage pre-incubated at 7 degree C for 5 days were 0.4 and 0.6 times higher than those of the anthers of late uninucleate stage and non-treated control. However, the number of calli with green plantlets and the number of regenerated green plantlets per 100 anthers cultured were 3.1 and 4.1 times higher for the calli from the anthers at late-uninucleate stage than those from the anthers at mid-uninucleate stage; the calli with green plantlets increased with the time of anther incubation (35 days, 7.7%; 45 days, 10.6%; 55 days, 16.7%). However, the ability was lost for all calli 65 days after incubation. The highest ability of green plant regeneration for the calli transferred by 35 days after incubation and differentiated green plantlets at about 25th day after transfer to regeneration medium, which reached 443.6 plants per 100-anthers cultured and was much higher than that of the calli transferred and differentiated green plantlets later. 20 Gy of gamma irradiation at the time when about 5% anthers produced calli by 35 days after incubation has a great positive effects on induction of calli, differentiation and regeneration of green plantlets. The number of callus formation, calli with green plantlets and green plantlets regenerated per 100-anthers culturentlets regenerated per 100-anthers cultured were 0.5, 22 and 306 times higher than those of non-irradiated control respectively

 
 
 
 
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Development of a short duration upland rice mutant line through anther culture of gamma irradiated plants  

International Nuclear Information System (INIS)

This experiment was conducted in the field and at the tissue culture laboratory of the Plant Physiology Division, CARI, Yezin from 1994 to 1997. Upland rice, Yar-2 was used as the test variety. Dried seeds (14% moisture content) were treated with gamma rays at doses of 0, 300, 350, 400 and 450 Gy respectively. These seeds were planted separately according to the gamma-ray treatment they received. At booting stage, tillers were cut. Anthers from the top and middle portion of the panicle were taken. The pollen, at developmental stage in each anther, was examined using Acetocarmine dye. Pollens at the uninucleate to early binucleare stage were selected. Tillers having pollens at the above-mentioned stage were placed in a dark room at 25(±) 1 C and 16 hours photoperiod. When plantlets were obtained from these media, well-developed green plantlets were selected and planted in Yoshida solution to attain vigorous root growth. Diploid and haploid plants were formed from the anther culture method. At the heading stage, haploid plants were treated with colchicines to promote development into diploid plants. At maturity, plants produced from materials treated with different gamma doses were harvested separately. These homozygous lines were planted in the field and the characters were compared with their parents grown at the same time. The highest callus induction rate was found in materials treated with 450 Gy of gamma rays, but the lowest green plant regeneration rate was alsost green plant regeneration rate was also observed at this dose. Among the forty-five homozygous lines obtained of the above materials, 7 lines, all from the 450 Gy gamma rays treated material, flowered earlier than the parents. One of the 7 early flowering lines, mutant line No 18, matured 19 days earlier but had the same yield as the parent. All other lines had a lower yield than the parent. Comparisons of yield and yield components of mutant line 18 and Yar-2 (parent) and comparison of quality characters are shown in tables

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Molecular characterization of three anther tissue culture varieties of tobaco (Nicotiana tabacum L. using RAPD analysis  

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Full Text Available Randomly Amplified Polymorphic DNA (RAPO analysis was used to characterize two new Flue Cured and one black tobacco type varieties derived from in vitro anther tissue culture technique. RAPOs are proposed as an appropriate complement of the morphoagronomic characteristics evaluations to fulfil international seed registration standards established for the identification of tobacco varieties. The identification of three tobacco varieties and their parents was carried out using the RAPO analysis with 64 random primers. Polymorphic products, 214 in number, were amplified only from 14 primers. Statistical analysis realized with the NTSYS program version 1.2 using the Jaccard similarity coefficient. The visual inspection revealed that five primers allowed the separation of the varieties in two groups, according to the type of tobacco: the Flue Cured and Black; while a group of nine primers separates each variety and establish its genetic relationship with their parents. The results obtained show that this technique is appropiated to establish genetic differences between tobacco varieties.

Gloria Azucena Fernández B.

2011-12-01

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Anther culture of wheat (Triticum aestivum L.) F1's and their reciprocal crosses.  

Science.gov (United States)

Anthers from three sets of wheat (Triticum aestivum L. em. Thell) F1's and their reciprocal crosses, made between parental lines differing greatly in their ability to produce microspore derived callus, were cultured on the Chinese potato medium so that we could 1) more clearly define the role of nuclear or cytoplasmic factors within T. aestivum in transferring the ability to undergo in vitro androgenesis, and 2) to briefly review the gametic representation and disease screening potential of the resulting polyhaploid wheat plants. The microspore derived calli values from F1's were slightly less than the midparental value. Statistical analysis indicated that the ability of each F1 to produce callus either did not significantly differ from that of the respective parental line having the highest androgenic yield or it exceeded its respective parental line having the lowest yield. No differences were noted between the members of each pair of reciprocal crosses. The results indicate that the transfer of in vitro androgenic ability to F1 hybrids is not dependent upon the maternal cytoplasm source. Polyhaploid plants, carrying the Pm 3 a powdery mildew resistance gene, expressed resistance to culture 4 a of powdery mildew. PMID:24270565

Bullock, W P; Baenziger, P S; Schaeffer, G W; Bottino, P J

1982-06-01

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Regeneration of flax ( Linum usitatissimum L.) plants from anther culture and somatic tissue with increased resistance to Fusarium oxysporum.  

Science.gov (United States)

The aim of this study was to establish a protocol for the efficient production of flax plants of microspore origin. The results were compared to those obtained for plants regenerated from somatic explants from hypocotyls, cotyledons, leaves, stems and roots. All the plants obtained during the experiments were regenerated from callus that was grown for periods from a few weeks to a few months before the regeneration was achieved. Anther cultures were less effective in plant regeneration than somatic cell cultures. However, regenerants derived from anther cells showed valuable breeding features, including increased resistance to fungal wilt. The age of the donor plants and the season they grew in had a noticeable effect on their anther callusing and subsequent plant regeneration. Low temperature had a negative effect and dark pre-treatment a positive effect on callusing and plant regeneration. Different media were most effective for callus induction, shoot induction and rooting. For callus induction two carbon sources (2.5% sucrose and 2.5% glucose) were most effective; for shoots, only sucrose at lower concentration (2%) was effective. Rooting was most efficient in 1% sucrose and reduced (50%) mineral concentration in the medium. It was found that the length of in vitro cultivation significantly increases the ploidy and affects such features as regenerant morphological characteristics, petal colour, and resistance to Fusarium oxysporum-induced fungal wilt. The established plant regeneration system provides a basis for the creation of transgenic flax. PMID:12827441

Rutkowska-Krause, I; Mankowska, G; Lukaszewicz, M; Szopa, J

2003-09-01

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Ensuring Reproduction at High Temperatures: The Heat Stress Response during Anther and Pollen Development  

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Full Text Available Sexual reproduction in flowering plants is very sensitive to environmental stresses, particularly to thermal insults which frequently occur when plants grow in field conditions in the warm season. Although abnormalities in both male and female reproductive organs due to high temperatures have been described in several crops, the failure to set fruits has mainly been attributed to the high sensitivity of developing anthers and pollen grains, particularly at certain developmental stages. A global view of the molecular mechanisms involved in the response to high temperatures in the male reproductive organs will be presented in this review. In addition, transcriptome and proteomic data, currently available, will be discussed in the light of physiological and metabolic changes occurring during anther and pollen development. A deep understanding of the molecular mechanisms involved in the stress response to high temperatures in flowers and, particularly, in the male reproductive organs will be a major step towards development of effective breeding strategies for high and stable production in crop plants.

Filomena Giorno

2013-07-01

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Effects of Genotype on Induction of Callus and Plant Regeneration Potential in vitro Anther Culture of Rice (Oryza sativa L.  

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Full Text Available The present studies were carried out to evaluate the response of anthers of six rice genotypes to callus induction and plant regeneration. For callus induction Z2 media supplemented with 2, 4-D 0.5 mg l-1, NAA 2.5 mg l-1 and Kinetin 0.5 mg l- was used. Of the six genotypes, five gave good callusing response. Highest callus induction was observed in BRRI Dhan-29 (8.06% and lowest in BR-10 (1.42%. Callus induction frequency varied from 1.42-8.06% depending on genotypes. Modified MS medium supplemented with Kinetin 0.5 mg l-1, BAP 2 mg l-1 and NAA 1.0 mg l-1 was used for plant regeneration. The results showed a significant genotypic difference in callus induction and plant regeneration. The regeneration of plantlet from anther derived calli ranged from 57-75% conclusion.

Sharmin Shahnewaz

2004-01-01

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Effect of Plant Growth Regulators on Callus Induction and Plant Regeneration in Anther Culture of Rice  

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An experiment was conducted to find the effects of different concentrations and combinations of growth regulators viz. 2, 4 D, IAA, ?-NAA and Kinetin on callus induction from the anthers of a commercial hybrid rice line IR-69690, developed by Bangladesh Rice Research Institute and subsequent plant regeneration. N6 medium was used as basal medium. Callus induction frequencies in different media combinations ranged from 1.2 to 35.5%. The medium supplemented with 2, 4 D 1 mg L-1<...

Md. Monirul Islam; Sanjay Kumar Adhikary; Purnendu Gain; Md Mizanur Rahman; Noor-e-Alam Siddique

2004-01-01

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Callus and Green Spot Formation From Anther Culture of Chili Mutant Lines (Capsicum Annum.L) Using in-vitro Culture  

International Nuclear Information System (INIS)

Callus and green spot formation from anther culture of chili mutant lines (Capsicum annum.L) were carried out using in-vitro culture. Two kinds of different media based on hormonal composition were used for callus induction. A half of an quantities were directly cultured on callus induction medium, while rest of them were treated with cold shock (4oC) for 3 and 6 days subsequently cultured on callus induction medium. The highest callus formation was observed in culture from Ac medium containing I mg/l 2,4-D and 0,1 mg/l kinetin and were obtained from 0 days cold shock with chili without irradiation (Kr 0) 30%, chili mutant lines with irradiation dose 20 Krad (Kr 20) 25% and chili mutant lines with irradiation dose 40 Krad (Kr 40) 30% respectively. While cold shock for 3 days increasing 15 % callus formation from Kr 40 mutant lines

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Effect of Plant Growth Regulators on Callus Induction and Plant Regeneration in Anther Culture of Rice  

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Full Text Available An experiment was conducted to find the effects of different concentrations and combinations of growth regulators viz. 2, 4 D, IAA, ?-NAA and Kinetin on callus induction from the anthers of a commercial hybrid rice line IR-69690, developed by Bangladesh Rice Research Institute and subsequent plant regeneration. N6 medium was used as basal medium. Callus induction frequencies in different media combinations ranged from 1.2 to 35.5%. The medium supplemented with 2, 4 D 1 mg L-1, ?-NAA 2 mg L-1 and Kinetin 1 mg L-1 was found most effective for callus induction (35.5%. Regeneration of plants from the callus on agarified MS medium supplemented with ?-NAA 0.5 mg L-1 and Kinetin 3 mg L-1 was also variable and ranged from 16.7 to 69.3%. Calli derived from the media supplemented with 2, 4 D 1 mg L-1, ?-NAA 2 mg L-1 and Kinetin 1 mg L-1 also showed better performance for plant regeneration (69.3% and among these plants 56.14% were green. However the callus induction medium containing ?-NAA 1 mg L-1 and Kinetin 1 mgL-1 directly produced green regenerated plants in higher frequency (70%, without transferring the calli on to the regeneration medium; but rate of callus induction in this medium was very low (6%.

Md. Monirul Islam

2004-01-01

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Anthere culture of tetraploid somatic hybrids as a crucial tool for starting Practical introgression breeding from allied species in eggplant (S. melongena L.)  

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The major limits for practical exploitation of the somatic hybrids between eggplant and its wild relatives has been their sterility and tetraploidy which have prevented their incorporation into breeding programs. We successfully employed anther culture to bring back the ploidy level to the diploid status of tetraploid interspecific hybrids between eggplant and the allied species S. integrifolium (=S. aethiopicum gr aculeatum) and S. aethiopicum gr gilo. Both the relative species are resistant...

Valentino, Danila; Tamietti, Giacomo

2007-01-01

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Ensuring Reproduction at High Temperatures: The Heat Stress Response during Anther and Pollen Development  

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Sexual reproduction in flowering plants is very sensitive to environmental stresses, particularly to thermal insults which frequently occur when plants grow in field conditions in the warm season. Although abnormalities in both male and female reproductive organs due to high temperatures have been described in several crops, the failure to set fruits has mainly been attributed to the high sensitivity of developing anthers and pollen grains, particularly at certain developmental stages. A glob...

Filomena Giorno; Mieke Wolters-Arts; Celestina Mariani; Ivo Rieu

2013-01-01

52

ps2, the gene responsible for functional sterility in tomato, due to non-dehiscent anthers, is the result of a mutation in a novel polygalacturonase gene  

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The recessive mutation ps-2, which appeared spontaneously in tomato, confers functional male sterility due to non-dehiscent anthers. In this study, we isolated and characterized the PS-2 gene. A single nucleotide mutation in a novel tomato polygalacturonase gene is responsible for the ps-2 phenotype. The mutation in ps-2 is responsible for an alternative splicing during maturation of the pre-mRNA, which leads to an aberrant mRNA. Differentiation between ps-2 and wild type (PS-2) anthers only ...

Gorguet, B. J. M.; Schipper, E. H.; Lammeren, A. A. M.; Visser, R. G. F.; Heusden, A. W.

2009-01-01

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Adequação de meios de cultura de anteras e testes de genótipos de trigo / Culture medium, microenvironment and genotype effects on wheat anther culture  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Realizaram-se dois experimentos, o primeiro visando conhecer a capacidade androgênica de variedades de trigo e identificar as melhores condições para alcançar aquele objetivo, em termos de meios de cultura e microclima. No segundo, estudou-se maior número de variedades. No primeiro experimento, fora [...] m testadas as seguintes: PF 853031 e IAC 24, a primeira, usada como padrão; dois meios de cultura básicos, batata-2 e N6; duas auxinas, IAA e 2,4-D, nas doses de 3, 9 e 27 ìmol/L, e cinetina, nas doses de 2, 6, 12 e 24 ìmol/L. As anteras plaqueadas foram acondicionadas em sala fotoperiódica: (a) com 14 h de luz, 60 ìmol.m-2.s-1 (3.200 lux), à temperatura de 25°C, e (b) submetidas a pré-tratamento por quatro dias a 6°C e, em seguida, retornadas à condição a. Notou-se que a melhor combinação de tratamentos para a variedade IAC 24 foi o meio batata-2, 2,4-D a 27 .ìmol/L e cinetina 2 a 6 ìmol/L, por promover maior indução de estruturas androgênicas. Já para a variedade PF 853031, a mesma combinação de tratamentos, exceto 2,4-D a 9 µmol/L, promoveu também maior indução de estruturas androgênicas. Por outro lado, o pré-tratamento de quatro dias de frio causou maior indução de estruturas androgênicas em ambas as variedades. No segundo experimento, foram estudadas cinco variedades: PF 853048, usada como padrão, IAC 21, BH 1146, IAC 60 e Anahuac; dois meios de cultura básicos: batata-2 e N6; duas combinações hormonais: CH1 (10 µmol/L IAA e 30 ìmol/L de cinetina), e CH2 (10 ìmol/L de 2,4-D e 3,0 ìmol/L de cinetina). Observou-se maior indução de estruturas androgênicas para a 'PF 853048', seguida da 'Anahuac'. Todavia, somente foram obtidas plantas para a primeira. Essa constatação sugere que a capacidade androgênica seja controlada geneticamente no trigo. Na combinação hormonal 10 ìmol/L de 2,4-D e 3 ìmol/L de cinetina houve maior formação de estruturas androgênicas. Transplantaram-se as plantas regeneradas para vasos contendo solo, alocando-as em casa de vegetação para aclimatação, crescimento e florescimento. As plantas mostraram-se inférteis, mas produziram sementes após a duplicação pela técnica da colchicina. Abstract in english Experiments were carried out to establish conditions and to access varietal effects for wheat androgenesis. The varieties PF 853031, a standard known for androgenic capacity, and the IAC 24 of high agronomic value, were tested in two culture mediums, potato-2 and N6, including two auxins, IAA and 2. [...] 4-D, at 3, 9 and 27 ìmol/L, and kinetin, at 2, 6, 12 and 24 µmol/L. The experiment was installed in factorial design with six blocks and 20 anthers per plate (a block). About 5,760 anthers were plated per variety. The experiment was left in a photoperiodic room with (a) 14 h of cool fluorescent light, 60 ìmol.m-2.s-1 (3,200 lux), at temperature of 25°C, and (b) pretreated in dark at 6°C for four days, then backed to a. The variety IAC 24 showed higher androgenic capacity than the PF 853031 variety, in medium potato-2, 2.4-D at 27 ìmol/L and kinetin from 2 to 6 µmol/L. Cold treatment for four days was beneficial in improving androgenesis to both varieties. Five other varieties were studied, PF 853048, as a androgenic control, IAC 21, BH 1146, IAC 60 and Anahuac; two culture mediums, potato-2 and N6, along with two hormonal combinations, CH1 (IAA 10 µmol/L and kinetin 30 µmol/L) and CH2 (2.4-D 10µmol/L and kin 3 .mol/L) in the condition as (b) above. The standard variety PF 853048 ranked first and Anahuac, the second in terms of androgenic response. However, plants were only obtained from PF 853048. It is likely that the androgenic effect is under genotype control in wheat. The hormonal combination 10 µmol/L of 2.4-D and 3 µmol/L of kinetin were observed to induce higher androgenic response. Regenerated plants were potted and left to flower. All of them showed to be infertile, but produced seeds after colchicine treatment.

Luis Carlos da Silva, Ramos; Erica Yumi, Yokoo; Carlos Eduardo de Oliveira, Camargo.

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Adequação de meios de cultura de anteras e testes de genótipos de trigo Culture medium, microenvironment and genotype effects on wheat anther culture  

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Full Text Available Realizaram-se dois experimentos, o primeiro visando conhecer a capacidade androgênica de variedades de trigo e identificar as melhores condições para alcançar aquele objetivo, em termos de meios de cultura e microclima. No segundo, estudou-se maior número de variedades. No primeiro experimento, foram testadas as seguintes: PF 853031 e IAC 24, a primeira, usada como padrão; dois meios de cultura básicos, batata-2 e N6; duas auxinas, IAA e 2,4-D, nas doses de 3, 9 e 27 ìmol/L, e cinetina, nas doses de 2, 6, 12 e 24 ìmol/L. As anteras plaqueadas foram acondicionadas em sala fotoperiódica: (a com 14 h de luz, 60 ìmol.m-2.s-1 (3.200 lux, à temperatura de 25°C, e (b submetidas a pré-tratamento por quatro dias a 6°C e, em seguida, retornadas à condição a. Notou-se que a melhor combinação de tratamentos para a variedade IAC 24 foi o meio batata-2, 2,4-D a 27 .ìmol/L e cinetina 2 a 6 ìmol/L, por promover maior indução de estruturas androgênicas. Já para a variedade PF 853031, a mesma combinação de tratamentos, exceto 2,4-D a 9 µmol/L, promoveu também maior indução de estruturas androgênicas. Por outro lado, o pré-tratamento de quatro dias de frio causou maior indução de estruturas androgênicas em ambas as variedades. No segundo experimento, foram estudadas cinco variedades: PF 853048, usada como padrão, IAC 21, BH 1146, IAC 60 e Anahuac; dois meios de cultura básicos: batata-2 e N6; duas combinações hormonais: CH1 (10 µmol/L IAA e 30 ìmol/L de cinetina, e CH2 (10 ìmol/L de 2,4-D e 3,0 ìmol/L de cinetina. Observou-se maior indução de estruturas androgênicas para a 'PF 853048', seguida da 'Anahuac'. Todavia, somente foram obtidas plantas para a primeira. Essa constatação sugere que a capacidade androgênica seja controlada geneticamente no trigo. Na combinação hormonal 10 ìmol/L de 2,4-D e 3 ìmol/L de cinetina houve maior formação de estruturas androgênicas. Transplantaram-se as plantas regeneradas para vasos contendo solo, alocando-as em casa de vegetação para aclimatação, crescimento e florescimento. As plantas mostraram-se inférteis, mas produziram sementes após a duplicação pela técnica da colchicina.Experiments were carried out to establish conditions and to access varietal effects for wheat androgenesis. The varieties PF 853031, a standard known for androgenic capacity, and the IAC 24 of high agronomic value, were tested in two culture mediums, potato-2 and N6, including two auxins, IAA and 2.4-D, at 3, 9 and 27 ìmol/L, and kinetin, at 2, 6, 12 and 24 µmol/L. The experiment was installed in factorial design with six blocks and 20 anthers per plate (a block. About 5,760 anthers were plated per variety. The experiment was left in a photoperiodic room with (a 14 h of cool fluorescent light, 60 ìmol.m-2.s-1 (3,200 lux, at temperature of 25°C, and (b pretreated in dark at 6°C for four days, then backed to a. The variety IAC 24 showed higher androgenic capacity than the PF 853031 variety, in medium potato-2, 2.4-D at 27 ìmol/L and kinetin from 2 to 6 µmol/L. Cold treatment for four days was beneficial in improving androgenesis to both varieties. Five other varieties were studied, PF 853048, as a androgenic control, IAC 21, BH 1146, IAC 60 and Anahuac; two culture mediums, potato-2 and N6, along with two hormonal combinations, CH1 (IAA 10 µmol/L and kinetin 30 µmol/L and CH2 (2.4-D 10µmol/L and kin 3 .mol/L in the condition as (b above. The standard variety PF 853048 ranked first and Anahuac, the second in terms of androgenic response. However, plants were only obtained from PF 853048. It is likely that the androgenic effect is under genotype control in wheat. The hormonal combination 10 µmol/L of 2.4-D and 3 µmol/L of kinetin were observed to induce higher androgenic response. Regenerated plants were potted and left to flower. All of them showed to be infertile, but produced seeds after colchicine treatment.

Luis Carlos da Silva Ramos

1994-01-01

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Cultivo in vitro de anteras de lino (Linum usitatissimum L.) / In Vitro Flax (Linum usitatissimum L.) Anthers Culture  

Scientific Electronic Library Online (English)

Full Text Available SciELO Argentina | Language: Spanish Abstract in spanish El cultivo de lino (Linum usitatissimum L.) es una alternativa productiva de interés para Entre Ríos y sus cualidades nutricionales hacen prever un incremento de la demanda en el mercado nacional e internacional. El mejoramiento genético es un instrumento que permite obtener nuevos genotipos adaptad [...] os a las condiciones constantemente cambiantes. El cultivo de anteras es considerado el método más eficiente de producción de plantas doble haploides de lino, y puede utilizarse como una biotecnología que asista a los programas de mejoramiento a fin de incrementar su eficiencia al permitir la obtención de líneas puras en un corto tiempo. Si bien el lino se ha mostrado recalcitrante para esta técnica, a través de la investigación que se presenta se lograron ajustes en el protocolo de cultivo de anteras in vitro, se llegó al correcto desarrollo de la etapa de callogénesis y se redujo sustancialmente la oxidación de los callos durante la etapa de regeneración. Abstract in english Flax (Linum usitatissimum L.) is an important oil crop and an interesting agriculture production activity in Entre Ríos. Its nutritional qualities provide a high expectation for an increased national and international commercial demand. Crop genetic improvement is a tool that allows obtaining new ge [...] notypes adapted to constantly changing conditions. Consumers look for better nutrition qualities and farmers needs new genotypes adapted to the ecological and climatic requirements. Anther culture is considered the most successful method of producing doubled haploid plants in flax and it can be used in flax breeding programs to increase the efficiency and obtain lines in a short time. Although flax appeared to be recalcitrant to this technology through the study here presented some adjustments in the protocols that allowed obtaining a suitable growth at callus stage and reduced in a significant manner the calluses oxidation during the regeneration stage were made.

Sergio, Lassaga; Adriana, Bretón; Lucrecia, Gieco; Héctor, Milisich; Alberto, Dittrich.

2010-05-01

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Investigation of the effect of 137Cs treatment on callus induction and plant regeneration anther culture in rice  

International Nuclear Information System (INIS)

Anthers at a single-nucleus stage of dihaploid L44 line have been treated with 1000, 2000 and 3000 R (137Cs). Irradiation has shown general inhibition effect on the induction of callus of the anthers inoculated. It is thought that the treatment effect is connected with the switching of the microspores from gametophytous to sporophytous type of development. The number of the albino regenerates increases along with the increase in irradiation dose. It could be explained by the mutation effect of 137Cs on the multiple genes controlling the pigment-protein complex. 2 tabs., 10 refs

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Histochemical and immunohistochemical identification of laticifer cells in callus cultures derived from anthers of Hevea brasiliensis.  

Science.gov (United States)

Laticifers are highly specialized cells present in over 20 plant families. They are well defined in planta. In vitro development of laticifers was also observed in some plants, but uncertain in the callus cultures of rubber tree, one of the most economically important latex producing plants. In the present study, we provide evidence that laticifer cells present in the callus cultures of rubber tree by histochemical and immunohistochemical studies. They present in the callus mainly as separate non-elongated form, a novel morphology different from the morphology of laticifer cells in planta, excluding their origin from explants. The occurring frequency of laticifer cells in the callus was genotype-dependent and negatively correlated with the somatic embryogenetic ability, suggesting that the presence of laticifer cells in the callus inhibit somatic embryogenesis in tissue culture of rubber tree. The genotypes PR107, RRIM600, Reyan8-79, and Reyan7-33-97 with lower embryogenetic ability compared to Haiken 2 had more laticifer cells, and laticifer clusters were only observed in these genotypes. PMID:21301851

Tan, Deguan; Sun, Xuepiao; Zhang, Jiaming

2011-06-01

58

In vitro Plant Regeneration Through Anther Culture of Some Iranian Local Rice (Oryza sativa L.) Cultivars  

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In this study, effect of different genotypes, different callus induction and regeneration media were investigated using seven Iranian local rice. Anthers were cultured on N6, Fj and L8 media containing the same hormonal combination 3 mg L-1 NAA, 0.5 mg L-1 Kn and 0.5 mg L-1 2, 4-D and incubated at 25± 1° C in dark for callus induction. All varieties in L8 medium, five varieties in Fj medium and six varieties in N6 medium produced highest percentage of callus...

Reza Talebi; Mohammad Reza Rahemi; Habibolah Arefi; Mohammad Nourozi; Nadali Bagheri

2007-01-01

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Anther development stage and gamma radiation effects on tomato anther-derived callus formation  

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Two experiments were carried (I) to determine tomato anther development stage influence on callus production; and (II) to investigate gamma radiation effects on anther culture. In the first experiment, anthers of a tomato hybrid (IPA 5 x Rotam 4-F1) were grown on three media. Although calli were induced at all stages of anther development, varying from prophase I to mono nucleate microspore, callus frequency decreased as anther development progressed and calli induction were not significantly affected by all media tested. Anthers containing prophase I meiocytes produced the highest calli frequency. Anther and flower bud length both were significantly correlated with anther development stage. In the second experiment, seed and floral buds of tomato hybrids IPA 5 x Rotam 4 (F2), IPA 6 x Rotam 4 (F2) and IPA 8 x 217.1 (F2) were submitted to gamma-ray and anthers were plated on two media described by Gresshoff and Doy (1972) supplemented with 2.0 mg L-1 NAA + 5.0 mg L-1 KIN and 2.0 mg L-1 NAA + 1.0 mg L-1 KIN. No significant differences for genotype and dosage testes were found for calli formation. (author)

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Effects of Genotype on Induction of Callus and Plant Regeneration Potential in vitro Anther Culture of Rice (Oryza sativa L.)  

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The present studies were carried out to evaluate the response of anthers of six rice genotypes to callus induction and plant regeneration. For callus induction Z2 media supplemented with 2, 4-D 0.5 mg l-1, NAA 2.5 mg l-1 and Kinetin 0.5 mg l- was used. Of the six genotypes, five gave good callusing response. Highest callus induction was observed in BRRI Dhan-29 (8.06%) and lowest in BR-10 (1.42%). Callus induction frequency varied from 1.42-8.06% de...

Sharmin Shahnewaz; Bari, M. A.; Siddique, N. A.; Rahman, M. H.

2004-01-01

 
 
 
 
61

Culturally responsive mathematics education  

CERN Document Server

This critical new collection presents mathematics education from a culturally responsive perspective and offers a broad perspective of mathematics as a significant, liberating intellectual force in our society.

Greer, Brian; Powell, Arthur B; Nelson-Barber, Sharon

2009-01-01

62

Segregation distortion in homozygous lines obtained via anther culture and maize doubled haploid methods in comparison to single seed descent in wheat (Triticum aestivum L.)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in english Background The quality of wheat grain depends on several characteristics, among which the composition of high molecular weight glutenin subunits, encoded by Glu-1 loci, are the most important. Application of biotechnological tools to accelerate the attainment of homozygous lines may influence the pr [...] oportion of segregated genotypes. The objective was to determine, whether the selection pressure generated by the methods based on in vitro cultures, may cause a loss of genotypes with desirable Glu-1 alleles. Results Homozygous lines were derived from six winter wheat crosses by pollination with maize (DH-MP), anther culture (DH-AC) and single seed descent (SSD) technique. Androgenetically-derived plants that originated from the same callus were examined before chromosome doubling using allele-specific and microsatellite markers. It was found that segregation distortion in SSD and DH-MP populations occurred only in one case, whereas in anther-derived lines they were observed in five out of six analyzed combinations. Conclusions Segregation distortion in DH-AC populations was caused by the development of more than one plant of the same genotype from one callus. This distortion was minimized if only one plant per callus was included in the population. Selection of haploid wheat plants before chromosome doubling based on allele-specific markers allows us to choose genotypes that possess desirable Glu-1 alleles and to reduce the number of plants in the next steps of DH production. The SSD technique appeared to be the most advantageous in terms of Mendelian segregation, thus the occurrence of residual heterozygosity can be minimized by continuous selfing beyond the F6 generation.

Tadeusz, Adamski; Karolina, Krystkowiak; Anetta, Kuczynska; Krzysztof, Mikolajczak; Piotr, Ogrodowicz; Aleksandra, Ponitka; Maria, Surma; Aurelia, Slusarkiewicz-Jarzina.

2014-01-15

63

Building Culturally Responsive Communities  

Science.gov (United States)

This article offers a variety of culturally responsive approaches and activities so as to better know and understand our students' diverse cultural and linguistic backgrounds. These methods will not only help to make more equitable classrooms where we make meaningful connections with our students--but also yield useful data so as to inform our…

Polleck, Jody; Shabdin, Shirin

2013-01-01

64

Correlations between low-temperature tolerance of anther donor clones of potato and the production of anther-derived embryos and calli at low temperatures.  

Science.gov (United States)

The main purpose of this study was to investigate whether the degree of tolerance to low non-freezing temperatures of immature microspores in anther culture was correlated to the degree of low-temperature tolerance, measured by chlorophyll fluorescene, in the anther donor clone. Anther cultures of six tetraploids and eight dihaploids, derived from anther cultures of clone 199.13, were incubated at 10, 15, 20, 25 or 30 °C respectively. The embryo and callus production were determined and subsequently two quotients/clone, designated "temperature-related embryo and callus production," were established. The quotients were defined as embryo and callus production at 10 or 15 °C divided by the embryo and callus production, for the individuals clone, at the optimal temperature (20 or 25 °C) for the same production. These quotients were thereafter correlated to the low-temperature tolerances of the anther donors. The tetraploid and dihaploid group were treated separately and significant positive correlations were found in both cases. This indicates that tolerance to low temperatures is expressed in the anther donor plant as well as in the microspores grown in anther culture. It is suggested that in vitro selection through anther culture may be a useful tool for breeding for increased tolerance to low temperatures in potato. PMID:24166633

Calleberg, E K

1996-06-01

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AMS-dependent and independent regulation of anther transcriptome and comparison with those affected by other Arabidopsis anther genes  

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Full Text Available Abstract Background In flowering plants, the development of male reproductive organs is controlled precisely to achieve successful fertilization and reproduction. Despite the increasing knowledge of genes that contribute to anther development, the regulatory mechanisms controlling this process are still unclear. Results In this study, we analyzed the transcriptome profiles of early anthers of sterile mutants aborted microspores (ams and found that 1,368 genes were differentially expressed in ams compared to wild type anthers, affecting metabolism, transportation, ubiquitination and stress response. Moreover, the lack of significant enrichment of potential AMS binding sites (E-box in the promoters of differentially expressed genes suggests both direct and indirect regulation for AMS-dependent regulation of anther transcriptome involving other transcription factors. Combining ams transcriptome profiles with those of two other sterile mutants, spl/nzz and ems1/exs, expression of 3,058 genes were altered in at least one mutant. Our investigation of expression patterns of major transcription factor families, such as bHLH, MYB and MADS, suggested that some closely related homologs of known anther developmental genes might also have similar functions. Additionally, comparison of expression levels of genes in different organs suggested that anther-preferential genes could play important roles in anther development. Conclusion Analysis of ams anther transcriptome and its comparison with those of spl/nzz and ems1/exs anthers uncovered overlapping and distinct sets of regulated genes, including those encoding transcription factors and other proteins. These results support an expanded regulatory network for early anther development, providing a series of hypotheses for future experimentation.

Ma Xuan

2012-02-01

66

Cultural Studies, Pedagogy, and Response-Ability  

Science.gov (United States)

A few years ago, in a tutorial in an advanced level undergraduate subject that she teaches--"Emotions, Culture and Community"--the author was a witness and participant in a pedagogical event that moved and provoked the class: It incited response-ability. This article is about that event, the meaning of response-ability, and the window that it…

Rossiter, Penelope

2012-01-01

67

Responses of different genotypes on development of callus from anther cultures of wheat  

International Nuclear Information System (INIS)

Uninuclear microspores of 20 different genotypes of wheat (Triticum aestivum L.) were cultivated on three different induction media. Callus formation rates ranged from 1-66% (on average 13% in 1984 and 35% in 1985). The highest percentage of callus formation (66.2) was from F1 of Yugoslavia X Top, cultivated on inductive Murashige and Skoog agar medium supplemented with 2.5 mg/L 2,4-dichlorophenoxyacetic acid, 0.5 mg/L naphthaleneacetic acid and 10% potato extract. (author)

68

Microarray and differential display identify genes involved in jasmonate-dependent anther development.  

Science.gov (United States)

Jasmonate (JA) is a signaling compound essential for anther development and pollen fertility in Arabidopsis. Mutations that block the pathway of JA synthesis result into male sterility. To understand the processes of anther and pollen maturation, we used microarray and differential display approaches to compare gene expression pattern in anthers of wild-type Arabidopsis and the male-sterile mutant, opr3. Microarray experiment revealed 25 genes that were up-regulated more than 1.8-fold in wild-type anthers as compared to mutant anthers. Experiments based on differential display identified 13 additional genes up-regulated in wild-type anthers compared to opr3 for a total of 38 differentially expressed genes. Searches of the Arabidopsis and non-redundant databases disclosed known or likely functions for 28 of the 38 genes identified, while 10 genes encode proteins of unknown function. Northern blot analysis of eight representative clones as probes confirmed low expression in opr3 anthers compared with wild-type anthers. JA responsiveness of these same genes was also investigated by northern blot analysis of anther RNA isolated from wild-type and opr3 plants, In these experiments, four genes were induced in opr3 anthers within 0.5-1 h of JA treatment while the remaining genes were up-regulated only 1-8 h after JA application. None of these genes was induced by JA in anthers of the coil mutant that is deficient in JA responsiveness. The four early-induced genes in opr3 encode lipoxygenase, a putative bHLH transcription factor, epithiospecifier protein and an unknown protein. We propose that these and other early components may be involved in JA signaling and in the initiation of developmental processes. The four late genes encode an extensin-like protein, a peptide transporter and two unknown proteins, which may represent components required later in anther and pollen maturation. Transcript profiling has provided a successful approach to identify genes involved in anther and pollen maturation in Arabidopsis. PMID:13677466

Mandaokar, Ajin; Kumar, V Dinesh; Amway, Matt; Browse, John

2003-07-01

69

Culturally responsive caring in occupational therapy.  

Science.gov (United States)

The present study examined how practitioners conceptualized culture and used their understanding of a client's culture to provide culturally responsive caring. Descriptions of practice were elicited from experienced practitioners serving culturally diverse clients. Twelve practitioners completed a written questionnaire and participated in a telephone interview. Half of these same participants also participated in a follow-up interview, which was confirmatory in nature. Grounded theory methodologies were used to identify and conceptualize key processes inherent in these practitioners' descriptions of providing culturally competent care. Practitioners' perceptions of providing culturally responsive care were categorized into five interrelated constructs: building cultural awareness; generating cultural knowledge; applying cultural skills; engaging culturally diverse others; and exploring multiculturalism. One environmental construct, the diversity context was also defined in the data. Culturally responsive caring is described as a process of actively developing a synergistic relationship grounded in mutuality and an intentional respect for a person's cultures. The findings add to the discourse on cultural competency in occupational therapy and may help to examine conceptual models of cultural competency for the profession. Possible implications for culturally responsive professional development, education, practice and research are presented. PMID:17966110

Muñoz, Jaime Phillip

2007-01-01

70

Analysis of Anther Cell Differentiation  

Energy Technology Data Exchange (ETDEWEB)

This grant supports research on genes that regulate Arabidopsis anther development. The proposed research largely concerns that functions of two key regulatory genes: SPL and DYT1, which encode two putative transcription factors, as well as genes that interact with these genes. Last year, we reported progress in preparation for ChIP analysis with SPL and DYT1, in dyt1 and ams microarray experiments and initial data analysis, in functional analysis of one of the DYT1 target gene, MYB35.

Ma, Hong

2015-01-19

71

Efeitos de meios de cultura na formação de calos a partir de anteras de aspargo (Asparagus officinalis L.) / Effects of the culture media on the calli formation from Asparagus officinalis L. anthers  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Técnicas auxiliares, como a cultura de anteras, possibilitam melhor eficiência na obtenção de novos genótipos de aspargo. Neste trabalho, foram utilizadas anteras contendo grãos de pólen, no estágio uninucleado, dos híbridos 56x22-8 e 47x22-8, em meio MS, semi-sólido e líquido, com diferentes concen [...] trações de reguladores de crescimento: meio A - 0,5 mg/l BAP + 0,1 mg/l ANA + 0,5 mg/l 2,4-D + 20 g/l sacarose + 20 g/l glicose; meio B - 0,5 mg/l 2,4-D + 30 g/l sacarose; meio C - 3,0 mg/l ANA + 0,5 mg/l Kin + 30 g/l sacarose e meio D - 2,0 mg/l ANA + 0,5 mg/l Kin + 30 g/l sacarose. A formação de calos variou com o genótipo e o meio. Os meios líquidos apresentaram melhor eficiência na indução de calos do que os meios semi-sólidos. Para o híbrido 56x22-8 os melhores meios foram o A2 (líquido) com 80,5% de indução de calos e dentre os meios semi-sólidos, o meio D1 com 41,6% de calos formados. Para o híbrido 47x22-8, o mais eficiente foi o meio D2 (líquido), com 68,1% de calos formados e, dentre os meios semi-sólidos, o D2, com 15,2%. Não ocorreram diferenças significativas, estatisticamente, entre os meios líquidos nem entre os meios semi-sólidos. Abstract in english Anther culture is an auxiliary technique to obtain new genotypes. In this work, anthers with pollen grains in the uninucleated stage of hybrids 56x22-8 and 47x22-8 were cultured in MS medium, semi-solid and liquid, with different concentrations of growth regulators: medium A - 0,5 mg/l BAP + 0,1 mg/ [...] l NAA + 0,5 mg/1 2,4-D + 20 g/l sucrose + 20 g/l glucose; medium B - 0,5 mg/1 2,4-D + 30 g/l sucrose; medium C - 3,0 mg/l NAA + 0,5 mg/l Kin + 30 g/l sucrose and medium D - 2,0 mg/l NAA + 0,5 mg/l Kin + 30 g/l sucrose. Callus formation varied with the genotype and the medium. Liquid media showed more efficiency in callus development than the semi-solids. For the hybrids 56x22-8 the best media were the liquid A2 with 80,5% of callus induction and among the semi-solids the D1, with 41,6%. For the hybrid 47x22-8 were liquid D2 with 68,1% and semi solid D1 with 15,2%. No significant differences were observed among the liquid media nor among the semi-solidones.

Vera Lúcia, Bobrowski; José Antônio, Peters; Eliane, Augustin; Judith, Viégas.

1995-07-01

72

Efeitos de meios de cultura na formação de calos a partir de anteras de aspargo (Asparagus officinalis L. Effects of the culture media on the calli formation from Asparagus officinalis L. anthers  

Directory of Open Access Journals (Sweden)

Full Text Available Técnicas auxiliares, como a cultura de anteras, possibilitam melhor eficiência na obtenção de novos genótipos de aspargo. Neste trabalho, foram utilizadas anteras contendo grãos de pólen, no estágio uninucleado, dos híbridos 56x22-8 e 47x22-8, em meio MS, semi-sólido e líquido, com diferentes concentrações de reguladores de crescimento: meio A - 0,5 mg/l BAP + 0,1 mg/l ANA + 0,5 mg/l 2,4-D + 20 g/l sacarose + 20 g/l glicose; meio B - 0,5 mg/l 2,4-D + 30 g/l sacarose; meio C - 3,0 mg/l ANA + 0,5 mg/l Kin + 30 g/l sacarose e meio D - 2,0 mg/l ANA + 0,5 mg/l Kin + 30 g/l sacarose. A formação de calos variou com o genótipo e o meio. Os meios líquidos apresentaram melhor eficiência na indução de calos do que os meios semi-sólidos. Para o híbrido 56x22-8 os melhores meios foram o A2 (líquido com 80,5% de indução de calos e dentre os meios semi-sólidos, o meio D1 com 41,6% de calos formados. Para o híbrido 47x22-8, o mais eficiente foi o meio D2 (líquido, com 68,1% de calos formados e, dentre os meios semi-sólidos, o D2, com 15,2%. Não ocorreram diferenças significativas, estatisticamente, entre os meios líquidos nem entre os meios semi-sólidos.Anther culture is an auxiliary technique to obtain new genotypes. In this work, anthers with pollen grains in the uninucleated stage of hybrids 56x22-8 and 47x22-8 were cultured in MS medium, semi-solid and liquid, with different concentrations of growth regulators: medium A - 0,5 mg/l BAP + 0,1 mg/l NAA + 0,5 mg/1 2,4-D + 20 g/l sucrose + 20 g/l glucose; medium B - 0,5 mg/1 2,4-D + 30 g/l sucrose; medium C - 3,0 mg/l NAA + 0,5 mg/l Kin + 30 g/l sucrose and medium D - 2,0 mg/l NAA + 0,5 mg/l Kin + 30 g/l sucrose. Callus formation varied with the genotype and the medium. Liquid media showed more efficiency in callus development than the semi-solids. For the hybrids 56x22-8 the best media were the liquid A2 with 80,5% of callus induction and among the semi-solids the D1, with 41,6%. For the hybrid 47x22-8 were liquid D2 with 68,1% and semi solid D1 with 15,2%. No significant differences were observed among the liquid media nor among the semi-solidones.

Vera Lúcia Bobrowski

1995-07-01

73

Confronting the Marginalization of Culturally Responsive Pedagogy  

Science.gov (United States)

Globally, over the last two decades, attention to culturally responsive, multicultural approaches to teaching have largely been supplanted by standardized curricula and pedagogy that derive from neoliberal business models of school reform. In this essay, I discuss three factors that contribute to the marginalization of culturally responsive

Sleeter, Christine E.

2012-01-01

74

Culturally and linguistically responsive teaching: part I.  

Science.gov (United States)

As increasing numbers of culturally and linguistically diverse learners are enrolled in nursing programs and employed in nursing service agencies, nurse educators must be aware of their own culture and how it influences their teaching and understand the learning needs of a diverse group of learners. This article offers strategies for nurse educators for being culturally and linguistically responsive while also establishing an inclusive learning environment. J Contin Educ Nurs. 2015;46(2):62-64. PMID:25633302

Billings, Diane M

2015-02-01

75

Aligning Collaborative and Culturally Responsive Evaluation Approaches  

Science.gov (United States)

The authors, three African-American women trained as collaborative evaluators, offer a comparative analysis of collaborative evaluation (O'Sullivan, 2004) and culturally responsive evaluation approaches (Frierson, Hood, & Hughes, 2002; Kirkhart & Hopson, 2010). Collaborative evaluation techniques immerse evaluators in the cultural milieu of the…

Askew, Karyl; Beverly, Monifa Green; Jay, Michelle L.

2012-01-01

76

Culture and Crisis Response in New Zealand  

Science.gov (United States)

New Zealand is a bicultural nation, founded on the signing of the Treaty of Waitangi by the native Maori and the British Crown. It is also home to people from many countries, cultures and ethnicities. Therefore, culturally-relevant response to crisis events has become a significant aspect of the Ministry of Education's interdisciplinary Traumatic…

Annan, Jean; Dean, Shelley; Henry, Geoff; McGhie, Desiree; Phillipson, Roger

2010-01-01

77

Ação do etileno em combinação com thidiazuron, nitrato de prata e ácido acetilsalicílico na cultura de anteras de pimentão Ethylene action in combination with Thidiazuron (TDZ, silver nitrate (AgNO3 and acetylsalicylic acid on sweet pepper anther culture  

Directory of Open Access Journals (Sweden)

Full Text Available Verificou-se o efeito do etileno em combinação com o thidiazuron (TDZ, nitrato de prata (AgNO3 e ácido acetilsalicílico (AAS, na indução e regeneração de embriões em anteras de pimentão, genótipos F1 (PIX21C12#35 x Agronômico 08, (PIX21C04#4 x Linha 004, (PIX22C#31 x Linha 004, (PIX21C15#45 x Ikeda e (PIX22C#21 x Ikeda. Os botões foram coletados quando sépalas e pétalas tinham tamanhos aproximadamente iguais, correspondendo ao estádio de anteras com micrósporos uninucleados. As anteras foram inoculadas em placa de Petri contendo meio de cultura C adicionado de 4,5 mM de TDZ; meio C acrescido de 0,05 mM de 2,4-D, 0,05 mM de cinetina e 88,8 mM de AAS; meio C acrescido de 0,05 mM de 2,4-D, 0,05 mM de cinetina e 5,0 mg/L de AgNO3. Em seguida, foram colocadas em ambiente escuro a 35ºC durante oito dias e enriquecido com ethephon, por 0; 2; 4; 6 ou 8 dias num esquema fatorial com quatro repetições, sendo cada placa considerada uma parcela contendo 20 a 24 anteras.O período de permanência de quatro dias, em ambiente enriquecido com ethephon, e os meios com TDZ e AgNO3, foram os mais favoráveis à indução de anteras. O TDZ também promoveu maior indução de calos embriogênicos. As maiores taxas de necrose ocorreram no meio com AAS. Só ocorreu regeneração direta em plântulas no meio C acrescido de 5 mg/L de AgNO3, sendo oito dias o melhor período. Os genótipos mais responsivos foram PIX22C#31 x linha 004 e PIX22C#21 x Ikeda. Observou-se a formação de plântulas haplóides e diplóides mediante análise da ponta de raíz. Considerando-se que a regeneração foi direta, sem passar por calos, supõe-se que as plântulas diplóides obtidas sejam provenientes dos micrósporos, devendo portanto ter ocorrido uma diploidização in vitro.The influence of ethylene used in combination with Thidiazuron (TDZ, silver nitrate (AgNO3 and acetylsalicylic acid (ASA was evaluated on sweet pepper androgenesis of F1 genotypes (PIX21C12#35 x Agronômico 08, PIX21C04#4 x Line 004, PIX22C#31 x Line 004, PIX21C15#45 x Ikeda and PIX22C#21 x Ikeda. Floral buds were collected when sepals and petals were approximately of equal size, corresponding to the uninucleated stage of microspores. Anthers were placed in Petri dishes containing three mediums: C medium supplemented with TDZ (4.5mM; C medium plus 2,4-D (0,05mM, Kinetin (0.5mM and ASA (88,8mM or AgNO3 (5.0 mg/L. After inoculation, the anthers were kept in the environment with ethephon for 0, 2, 4, 6 or 8 days at 35ºC for eight days in the dark. The experiment was conducted in a factorial design with four replications. Each replicate consisted of one Petri dish containing 20-24 anthers. TDZ and AgNO3 were most effective for inducing somatic embryos after four days with Ethrel. The greatest rates of necrosis took place on the medium with AAS. Direct regeneration of plantlets occurred only on medium supplemented with 5 mg/L of AgNO3 after an eight-day treatment with Ethrel. The most responsive genotypes were PIX22C#31 x Line 004 and PIX22C#21 x Ikeda. Chromosome number of the seedlings was verified through the root tip analysis which indicated the presence of haploid and diploid chromosome number. Since regeneration was direct, ie without going through callus phase, it is hypothesized that the diploid seedlings came from in vitro diploidization.

José Magno Q. Luz

1999-11-01

78

Ação do etileno em combinação com thidiazuron, nitrato de prata e ácido acetilsalicílico na cultura de anteras de pimentão / Ethylene action in combination with Thidiazuron (TDZ), silver nitrate (AgNO3) and acetylsalicylic acid on sweet pepper anther culture  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Verificou-se o efeito do etileno em combinação com o thidiazuron (TDZ), nitrato de prata (AgNO3) e ácido acetilsalicílico (AAS), na indução e regeneração de embriões em anteras de pimentão, genótipos F1 (PIX21C12#35 x Agronômico 08), (PIX21C04#4 x Linha 004), (PIX22C#31 x Linha 004), (PIX21C15#45 x [...] Ikeda) e (PIX22C#21 x Ikeda). Os botões foram coletados quando sépalas e pétalas tinham tamanhos aproximadamente iguais, correspondendo ao estádio de anteras com micrósporos uninucleados. As anteras foram inoculadas em placa de Petri contendo meio de cultura C adicionado de 4,5 mM de TDZ; meio C acrescido de 0,05 mM de 2,4-D, 0,05 mM de cinetina e 88,8 mM de AAS; meio C acrescido de 0,05 mM de 2,4-D, 0,05 mM de cinetina e 5,0 mg/L de AgNO3. Em seguida, foram colocadas em ambiente escuro a 35ºC durante oito dias e enriquecido com ethephon, por 0; 2; 4; 6 ou 8 dias num esquema fatorial com quatro repetições, sendo cada placa considerada uma parcela contendo 20 a 24 anteras.O período de permanência de quatro dias, em ambiente enriquecido com ethephon, e os meios com TDZ e AgNO3, foram os mais favoráveis à indução de anteras. O TDZ também promoveu maior indução de calos embriogênicos. As maiores taxas de necrose ocorreram no meio com AAS. Só ocorreu regeneração direta em plântulas no meio C acrescido de 5 mg/L de AgNO3, sendo oito dias o melhor período. Os genótipos mais responsivos foram PIX22C#31 x linha 004 e PIX22C#21 x Ikeda. Observou-se a formação de plântulas haplóides e diplóides mediante análise da ponta de raíz. Considerando-se que a regeneração foi direta, sem passar por calos, supõe-se que as plântulas diplóides obtidas sejam provenientes dos micrósporos, devendo portanto ter ocorrido uma diploidização in vitro. Abstract in english The influence of ethylene used in combination with Thidiazuron (TDZ), silver nitrate (AgNO3) and acetylsalicylic acid (ASA) was evaluated on sweet pepper androgenesis of F1 genotypes (PIX21C12#35 x Agronômico 08, PIX21C04#4 x Line 004, PIX22C#31 x Line 004, PIX21C15#45 x Ikeda and PIX22C#21 x Ikeda) [...] . Floral buds were collected when sepals and petals were approximately of equal size, corresponding to the uninucleated stage of microspores. Anthers were placed in Petri dishes containing three mediums: C medium supplemented with TDZ (4.5mM); C medium plus 2,4-D (0,05mM), Kinetin (0.5mM) and ASA (88,8mM) or AgNO3 (5.0 mg/L). After inoculation, the anthers were kept in the environment with ethephon for 0, 2, 4, 6 or 8 days at 35ºC for eight days in the dark. The experiment was conducted in a factorial design with four replications. Each replicate consisted of one Petri dish containing 20-24 anthers. TDZ and AgNO3 were most effective for inducing somatic embryos after four days with Ethrel. The greatest rates of necrosis took place on the medium with AAS. Direct regeneration of plantlets occurred only on medium supplemented with 5 mg/L of AgNO3 after an eight-day treatment with Ethrel. The most responsive genotypes were PIX22C#31 x Line 004 and PIX22C#21 x Ikeda. Chromosome number of the seedlings was verified through the root tip analysis which indicated the presence of haploid and diploid chromosome number. Since regeneration was direct, ie without going through callus phase, it is hypothesized that the diploid seedlings came from in vitro diploidization.

José Magno Q., Luz; José Eduardo B. P., Pinto; Polyana Aparecida D., Ehlert; Estér Solange, Cerqueira; Ivan, Bedin.

1999-11-01

79

Improved Androgenesis of Broccoli (Brassica oleracea var italica Anthers Using Sucrose and Growth Regulators  

Directory of Open Access Journals (Sweden)

Full Text Available The presented study was conducted to study the effects of BAP and its combinations with 2, 4-D and sucrose concentrations on androgenesis of broccoli cv. ‘Arcadia’. The MS Basel media supplemented with AC (0.5 g L-1 and 3% sucrose was used. The experiment was laid out in Completely Randomized Design (CRD using 3 replicates. The effects of BAP in combination with 2, 4-D and sucrose concentrations on androgenesis of broccoli (cv Arcadia anther cultures were investigated. The MS basal media supplemented with activated charcoal (AC (0.5 g L-1 was used. The medium complemented with BAP (1 mg L-1 plus 2, 4-D (0.5 mg L-1 significantly increased the percentage of anthers developing embryos (90%. Increasing 2, 4-D concentration (1 mg L-1 significantly decreased the percentage of anthers formed embryos (10%. Regarding the regeneration of the formed embryos, the culture medium containing BAP (1 mg L-1+2, 4-D (0.5 mg L-1 or BAP (1 mg L-1+2, 4-D (1 mg L-1 produced the high percentages of embryos induced callus. The maximum percentage of embryos developed into plantlets were obtained with culture medium with BAP (1 mg L-1+2, 4-D (0.5 mg L-1 followed by BAP (1 mg L-1 and 2, 4-D (1 mg L-1. Concerning sucrose concentration, the culture medium with low sucrose concentration (20 g L-1 enhanced the percentage of anthers developed embryos. The higher sucrose concentrations (50 and 60 g L-1 increased percentages of dead anthers and anthers formed callus and decreased the percentage of embryos developing plantlets. BAP in combinations with 2, 4-D and low concentrations of sucrose can be successfully used to perform embryos and/or callus from the callus induction and embryos development either to callus or plants.

Magdi A.A. Mousa

2014-01-01

80

Dealing with Difference: Building Culturally Responsive Classrooms  

Directory of Open Access Journals (Sweden)

Full Text Available Australia continues to develop as a multicultural society with levels of immigration increasing significantly over recent years as a result of government policies. More recently, the new period of financial turmoil, continuing threats from terrorism and environmental concerns, have all exacerbated the challenges of dealing with difference in our society. In response, schools continue to face the challenges of the impact of a range of different cultures, languages and religions among their student and school communities. How effectively schools deal with difference and how well they are supported in their endeavours to build culturally response classrooms is a perennial issue for both teachers and educators. A major challenge for teachers is to at a minimum, understand cultural differences as they manifest in their particular school settings and to draw on approaches that support student learning in culturally appropriate ways so to assist them to better realise their full potential. In this paper we will consider cultural diversity in the context of recent school policies, highlight a number of frameworks for addressing cultural diversity in the classroom, in particular the approaches by Kalantzis and Cope’s (1999 and Hickling-Hudson (2003. We also draw on the findings from a recent qualitative study of representations of cultural diversity in a number of Sydney metropolitan schools to discuss the need for more greater resource and policy support for progressive teaching approaches that support the development of a more tolerant and inclusive multicultural society. Key words: cultural diversity, schools, teacher education, classroom practice, social inclusion

Nina Burridge

2009-11-01

 
 
 
 
81

In Vitro ANTHER CULTURE OF RICE HYBRIDS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

En el Laboratorio de Mejoramiento de Arroz y Maíz del CIFA "Las Torres", en Sevilla, España, auspiciado por un proyecto de investigación, comenzó a desarrollarse un programa de obtención de variedades, que incluía en sus objetivos la utilización del cultivo de anteras de híbridos. Para ello se evaluaron diferentes medios para la formación de callos y regeneración de plantas verdes así como anteras de híbridos F1, provenientes de 15 cruzamientos. Los resultados mostraron que los m?...

Rez, Noraida P. U. E.; Elena Admetlla; Aguilar, M.

2003-01-01

82

Ribulose Bisphosphate Carboxylase Activity in Anther-Derived Plants of Saintpaulia ionantha Wendl. Shag.  

Science.gov (United States)

Plants obtained from anther culture of the African violet, Saintpaulia ionantha Wendl. ;Shag' and vegetatively cloned copies of the parent anther donor plant were examined for their ploidy and ribulose-1,5-biphosphate carboxylase (RuBPcase) activity. The cloned parent plants were all diploid and did not vary much in their nuclear DNA, chlorophyll, and RuBPcase activity. Some of the anther-derived plants were similar to the parent plants while others were not. Different levels of ploidy were observed among the androgenetic plants. RuBPcase activities higher than that of the parent plants were found in some anther-derived plants. However, there was no direct correlation between ploidy and RuBPcase activity. Expression of nuclear genes from a single parent in the anther-derived plants and it's diploidization or plastid changes during early stages of microsporogenesis or androgenesis are suggested as possible reasons for the variations observed among them. This could be a useful technique to obtain physiological variants which could be agronomically desirable. PMID:16663273

Bhaskaran, S; Smith, R H; Finer, J J

1983-11-01

83

Toward a More Culturally Responsive General Music Classroom  

Science.gov (United States)

This article seeks to characterize culturally responsive teaching; consider how it differs from other pedagogical approaches in music education informed by culture, such as multicultural music education; and offer ideas for making the general music classroom more culturally responsive.

Abril, Carlos R.

2013-01-01

84

An Agenda to Strengthen Culturally Responsive Pedagogy  

Science.gov (United States)

Over the last two decades in many countries, culturally responsive, multicultural and bilingual approaches to teaching have largely been replaced by standardised curricula and pedagogy, rooted in a political shift toward neoliberalism that has pushed business models of school reform. I argue that neoliberal reforms, by negating the central…

Sleeter, Christine E.

2011-01-01

85

Transforming the Doping Culture : Whose responsibility, what responsibility?  

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The doping culture represents an issue for sport and for society. Normative debates on doping have been mainly concerned with questions of the justifiability of doping. The practice of assigning responsibility for doping behaviour has chiefly been individual-based, focusing mainly on the individual athlete’s doping behaviour. The overarching aim of this thesis is to investigate the relevance and the importance of the ideas of responsibility in relation to ethical debates on doping. The more...

Atry, Ashkan

2013-01-01

86

El turismo cultural. ¿Un negocio responsable? / Cultural Tourism. A Responsible Business?  

Scientific Electronic Library Online (English)

Full Text Available SciELO Argentina | Language: Spanish Abstract in spanish Cuestiones como la degradación el medioambiente, la pérdida de la diversidad cultural y especialmente lo considerado como patrimonio cultural y la ecología, son actualmente aspectos consustanciales a la vida cotidiana, a la política, a la planificación y a los negocios. En la Cumbre de la Tierra (Rí [...] o de Janeiro, 1992) se acuña el concepto Turismo Responsable en un intento de impulsar el respeto y la preservación, implicando en la tarea a todos los actores. Bajo el paraguas de la responsabilidad, uno de los productos con mayor crecimiento y demanda en la última década ha sido el turismo cultural, planteado ahora como una de las fórmulas para la consecución del desarrollo integral de los pueblos. En este artículo se repasa el turismo cultural como producto, su importancia en el nuevo orden turístico y su alcance, constatando como a través de él el sistema turístico ha tendido a implicarse en la gestión de la cultura y condicionarla por su rentabilidad. Abstract in english Environmental degradation, the loss of cultural diversity and especially what is considered cultural heritage and ecology, are actually the main issues of every day life, politics, planning and business. During the Rio Meeting (Rio de Janeiro, 1992) the concept of Responsible Tourism was born in an [...] attempt to enhance respect and preservation with all actors involved. Under the umbrella of responsibility, cultural tourism was one product that showed the biggest growth under the premises of the formula of all-embracing development of society. This article presents a revision of cultural tourism as a product, its importance for the new tourist order and its range and establishing in which way the tourist system had a tendency to get involved in cultural management and therefore as conditioned its profitability.

Agustín, Santana Talavera.

2008-12-01

87

Cell Culture Assay for Human Noroviruses [response  

Energy Technology Data Exchange (ETDEWEB)

We appreciate the comments provided by Leung et al., in response to our recently published article “In Vitro Cell Culture Infectivity Assay for Human Noroviruses” by Straub et al. (1). The specific aim of our project was to develop an in vitro cell culture infectivity assay for human noroviruses (hNoV) to enhance risk assessments when they are detected in water supplies. Reverse transcription (RT) qualitative or quantitative PCR are the primary assays for waterborne NoV monitoring. However, these assays cannot distinguish between infectious vs. non-infectious virions. When hNoV is detected in water supplies, information provided by our infectivity assay will significantly improve risk assessment models and protect human health, regardless of whether we are propagating NoV. Indeed, in vitro cell culture infectivity assays for the waterborne pathogen Cryptosporidium parvum that supplement approved fluorescent microscopy assays, do not result in amplification of the environmentally resistant hard-walled oocysts (2). However, identification of life cycle stages in cell culture provides evidence of infectious oocysts in a water supply. Nonetheless, Leung et al.’s assertion regarding the suitability of our method for the in vitro propagation of high titers of NoV is valid for the medical research community. In this case, well-characterized challenge pools of virus would be useful for developing and testing diagnostics, therapeutics, and vaccines. As further validation of our published findings, we have now optimized RT quantitative PCR to assess the level of viral production in cell culture, where we are indeed finding significant increases in viral titer. The magnitude and time course of these increases is dependent on both virus strain and multiplicity of infection. We are currently preparing a manuscript that will discuss these findings in greater detail, and the implications this may have for creating viral challenge pools

Straub, Tim M.; Honer Zu Bentrup, Kerstin; Orosz Coghlan, Patricia; Dohnalkova, Alice; Mayer, Brooke K.; Bartholomew, Rachel A.; Valdez, Catherine O.; Bruckner-Lea, Cindy J.; Gerba, Charles P.; Abbaszadegan, Morteza A.; Nickerson, Cheryl A.

2007-07-01

88

Organizational culture during the accident response process  

Energy Technology Data Exchange (ETDEWEB)

The ability of an organization to effectively move from an anticipatory to an ad hoc strategy may well depend on the organization having the ability to balance these two apparently dichotomous cultural styles. The organization which is most capable of making the necessary transition in an optimal manner may well exhibit some aspects of both cultural styles during normal operations. Data collected at one NPP does exhibit this pattern of results, with the organization exhibiting a clear hierarchical chain of command and perceived conventional behavioral expectations as well as exhibiting a more decentralized and collegial approach to decisionmaking, a team work orientation, and informal communications. Thus, it is expected that this organization possesses the capabilities to make a successful transition from an anticipatory to an ad hoc strategy. Data collected at a second NPP more strongly exhibits the traditional style suggested as being important during the anticipatory strategy, with more formal communications and bureaucratically controlled decision-making. This organization may experience difficulty if faced with the need to make a transition from an anticipatory to an ad hoc strategy. These conclusions are further validated based on observation of Emergency Preparedness Exercise Inspections, which suggest that the more anticipatory types of behaviors actually inhibit successful performance during an ad hoc response. The final validation of these hypotheses needs to be demonstrated with cultural data collected during emergency simulations. The mechanism to obtain such data during these types of situations is an area for future research.

Shurberg, D.A.; Haber, S.B.

1992-01-01

89

Organizational culture during the accident response process  

Energy Technology Data Exchange (ETDEWEB)

The ability of an organization to effectively move from an anticipatory to an ad hoc strategy may well depend on the organization having the ability to balance these two apparently dichotomous cultural styles. The organization which is most capable of making the necessary transition in an optimal manner may well exhibit some aspects of both cultural styles during normal operations. Data collected at one NPP does exhibit this pattern of results, with the organization exhibiting a clear hierarchical chain of command and perceived conventional behavioral expectations as well as exhibiting a more decentralized and collegial approach to decisionmaking, a team work orientation, and informal communications. Thus, it is expected that this organization possesses the capabilities to make a successful transition from an anticipatory to an ad hoc strategy. Data collected at a second NPP more strongly exhibits the traditional style suggested as being important during the anticipatory strategy, with more formal communications and bureaucratically controlled decision-making. This organization may experience difficulty if faced with the need to make a transition from an anticipatory to an ad hoc strategy. These conclusions are further validated based on observation of Emergency Preparedness Exercise Inspections, which suggest that the more anticipatory types of behaviors actually inhibit successful performance during an ad hoc response. The final validation of these hypotheses needs to be demonstrated with cultural data collected during emergency simulations. The mechanism to obtain such data during these types of situations is an area for future research.

Shurberg, D.A.; Haber, S.B.

1992-08-01

90

Organizational culture during the accident response process  

International Nuclear Information System (INIS)

The ability of an organization to effectively move from an anticipatory to an ad hoc strategy may well depend on the organization having the ability to balance these two apparently dichotomous cultural styles. The organization which is most capable of making the necessary transition in an optimal manner may well exhibit some aspects of both cultural styles during normal operations. Data collected at one NPP does exhibit this pattern of results, with the organization exhibiting a clear hierarchical chain of command and perceived conventional behavioral expectations as well as exhibiting a more decentralized and collegial approach to decisionmaking, a team work orientation, and informal communications. Thus, it is expected that this organization possesses the capabilities to make a successful transition from an anticipatory to an ad hoc strategy. Data collected at a second NPP more strongly exhibits the traditional style suggested as being important during the anticipatory strategy, with more formal communications and bureaucratically controlled decision-making. This organization may experience difficulty if faced with the need to make a transition from an anticipatory to an ad hoc strategy. These conclusions are further validated based on observation of Emergency Preparedness Exercise Inspections, which suggest that the more anticipatory types of behaviors actually inhibit successful performance during an ad hoc response. The final validation of these hypotheses needs to be demonstrated with cultural data collected during emergency simulations. The mechanism to obtain such data during these types of situations is an area for future research

91

Determination of Suitable Microspore Stage and Callus Induction from Anthers of Kenaf (Hibiscus cannabinus L.)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Kenaf (Hibiscus cannabinus L.) is one of the important species of Hibiscus cultivated for fiber. Availability of homozygous parent lines is prerequisite to the use of the heterosis effect reproducible in hybrid breeding. The production of haploid plants by anther culture followed by chromosome doubling can be achieved in short period compared with inbred lines by conventional method that requires self pollination of parent material. In this research, the effects of the microspore developmenta...

Ahmed Mahmood Ibrahim; Fatimah Binti Kayat; Zeti Ermiena Surya Mat Hussin; Dwi Susanto; Mohammed Ariffulah

2014-01-01

92

Effect of Genotype and Callus Induction Medium on Green Plant Regeneration from Anther of Nepalese Rice Cultivars  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Effects of genotype and medium composition on the frequency of callus induction and green plant regeneration from anther of Nepalese rice were investigated. Cold pretreated anthers from six rice genotypes at 8±2°C for seven days were cultured on three different callus induction media designated as Callus Induction Medium (CIM 1): N6 mineral salts + N6 vitamins (2 mg L-1 each) + myoinositol (100 mg L-1) + 2,4-D (2.5 mg L-1) + KI (0.5 mg L-1) + AgNO...

Niroula, R. K.; Bimb, H. P.

2009-01-01

93

Anther and pollen development in barley  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The control of pollen viability and release is of major commercial importance in the development of crops for hybrid seed production and selective breeding. It has been shown that key transcription factors in Arabidopsis particularly MALE STERILITY1 (MS1), are functionally conserved in rice (Li et al., 2011), therefore extending this comparative analysis and controlling fertility in temperate cereals, such as barley, is the long term goal of this project. Although anther and pollen develo...

Ferna?ndez, Jose?

2012-01-01

94

Some Anther Structures in Sanguisorba minor Scop. (Rosaceae  

Directory of Open Access Journals (Sweden)

Full Text Available In this study, investigation of some anther structures in Sanguisorba minor Scop. subsp. muricata was aimed. Therefore, anthers were squashed by modified glycerine-gelatine method and additionally different histochemical stainings also were tested. The result illustrated that in different parts of anther, such as marginal, connection tissue, starch and protein granules accumulated. Furthermore, during maturation these deposits were detected in pollen grains also. In addition, a very interesting feature, balloon-like structures filled by proteins, were observed in anther cavity. In the light of these findings, their importance on pollen development was discussed.

Mehmet Aybeke

2011-01-01

95

Culturally Responsible Pedagogy: "The Case of Josefina Guzman."  

Science.gov (United States)

Teacher educators are responsible for preparing teachers to be culturally responsive. The paper presents a case study of one middle school teacher with a diverse group of students who led her classroom in a culturally responsive manner, examining teacher conceptions of self/other, teacher/student relations, and conceptions of knowledge. (SM)

Huber, Tonya

1992-01-01

96

Culturally Responsive Teaching for American Indian Learners.  

Science.gov (United States)

Teachers in a multicultural society need to respect cultural differences, know the cultural resources their students bring to class, and be skilled at tapping into learners' cultural resources in the teaching-learning process. They must believe that all students are capable of learning, and they must implement an enriched curriculum for all…

Pewewardy, Cornel D.

97

Structural organization of the Oxytropis baschkiriensis Knjaz. developing anther  

Digital Repository Infrastructure Vision for European Research (DRIVER)

On the base of accurate anatomic-morphological data the formation and development of anther of Oxytropis baschkiriensis, rare endemic species from the South Ural flora, were investigated at the first time. It has been demonstrated that the anther and pollen grain developments are typical for the family Fabaceae.

Kruglova, Anna E.

2013-01-01

98

Project CRAFT: Culturally Responsive and Family-Focused Training.  

Science.gov (United States)

Describes the model, strategies, materials, and outcomes of Project CRAFT (Culturally Responsive and Family-focused Training), a training program in which culturally diverse family/professional teams were trained, supported, and mentored to provide inservice training on cultural competencies to service providers working with young children with…

Chen, Deborah; And Others

1997-01-01

99

Culturally Responsive: Art Education in a Global Era  

Science.gov (United States)

Facing the era of globalization, culturally responsive art teachers must recognize that students' home culture, including local artistic expression, is inevitably influenced by global forces. They should strive to engage with students systems and issues of globalization and its impact on their community culture and art. In this article, the author…

Lai, Alice

2012-01-01

100

Callus induction and plant regeneration of tomato (Lycopersicon esculentum cv. IPA 5 via anther culture Indução de calos e regeneração de plantas a partir do cultivo in vitro de anteras de tomate (Lycopersicon esculentum cv. IPA 5  

Directory of Open Access Journals (Sweden)

Full Text Available Different growth regulators combinations were tested on the production of anther callus in tomato cultivar IPA 5. Calli were induced on media supplemented with 1.0mgL-1 gibberellic acid (GA3, 0.05mgL-1 alpha-naphthaleneacetic acid (NAA plus 0.1mgL-1 6-benzylaminopurine (BAP, or with 1.0mgL-1 BAP plus 1.0mgL-1 NAA. The medium containing 1.0mgL-1 BAP and 1.0mgL-1 NAA produced the highest calli frequency, and promoted plant regeneration by indirect organogenesis, when calli were transferred to 0.01mgL-1 BAP and 0.001mgL-1 NAA. Plants regenerated presented tetraploid cells and rare diploid cells. These tetraploid plants could be used as source for further obtainment of trisomic lines, for the purpose of genic localization studies and protein compounds analysis.Diferentes combinações de reguladores de crescimento foram testadas na produção de calos a partir do cultivo de anteras de tomate cultivar IPA 5. Calos foram induzidos no meio suplementado com 1,0mgL-1 de ácido giberélico (GA3 + 0,05mgL-1 de alfa-ácido naftalenoacético (ANA + 0,1mgL-1 de 6-benzilaminopurina (BAP, ou com 1,0mgL-1 de BAP + 1,0mgL-1 de ANA. O meio contendo 1,0mgL-1 de BAP e 1,0mgL-1 de ANA produziu a maior freqüência de calos e promoveu a regeneração de plantas através de organogênese indireta, quando os calos foram transferidos para 0,01mgL-1 de BAP e 0,001mgL-1 de ANA. As plantas regeneradas apresentaram células tetraplóides e, raramente, células diplóides. Estas plantas tetraplóides podem servir como fonte para posterior obtenção de linhagens trissômicas, para serem utilizadas em estudos de localização gênica e em análises de compostos protéicos.

Ana Christina Rabello Brasileiro

1999-12-01

 
 
 
 
101

Callus induction and plant regeneration of tomato (Lycopersicon esculentum cv. IPA 5) via anther culture / Indução de calos e regeneração de plantas a partir do cultivo in vitro de anteras de tomate (Lycopersicon esculentum cv. IPA 5)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Diferentes combinações de reguladores de crescimento foram testadas na produção de calos a partir do cultivo de anteras de tomate cultivar IPA 5. Calos foram induzidos no meio suplementado com 1,0mgL-1 de ácido giberélico (GA3) + 0,05mgL-1 de alfa-ácido naftalenoacético (ANA) + 0,1mgL-1 de 6-benzila [...] minopurina (BAP), ou com 1,0mgL-1 de BAP + 1,0mgL-1 de ANA. O meio contendo 1,0mgL-1 de BAP e 1,0mgL-1 de ANA produziu a maior freqüência de calos e promoveu a regeneração de plantas através de organogênese indireta, quando os calos foram transferidos para 0,01mgL-1 de BAP e 0,001mgL-1 de ANA. As plantas regeneradas apresentaram células tetraplóides e, raramente, células diplóides. Estas plantas tetraplóides podem servir como fonte para posterior obtenção de linhagens trissômicas, para serem utilizadas em estudos de localização gênica e em análises de compostos protéicos. Abstract in english Different growth regulators combinations were tested on the production of anther callus in tomato cultivar IPA 5. Calli were induced on media supplemented with 1.0mgL-1 gibberellic acid (GA3), 0.05mgL-1 alpha-naphthaleneacetic acid (NAA) plus 0.1mgL-1 6-benzylaminopurine (BAP), or with 1.0mgL-1 BAP [...] plus 1.0mgL-1 NAA. The medium containing 1.0mgL-1 BAP and 1.0mgL-1 NAA produced the highest calli frequency, and promoted plant regeneration by indirect organogenesis, when calli were transferred to 0.01mgL-1 BAP and 0.001mgL-1 NAA. Plants regenerated presented tetraploid cells and rare diploid cells. These tetraploid plants could be used as source for further obtainment of trisomic lines, for the purpose of genic localization studies and protein compounds analysis.

Ana Christina Rabello, Brasileiro; Lilia, Willadino; Gianna Griz, Carvalheira; Marcelo, Guerra.

1999-12-01

102

[Genetic analysis of anthocyanin of the anthers and culm pigmentation in common wheat].  

Science.gov (United States)

Anthocyanin pigmentation of various organs develops during plant ontogeny in response to adverse and damaging abiotic and biotic stressors (environmental factors). Using the monosome method, the genes responsible for anther and culm anthocyanin pigmentation (Pan1 and Pc2, respectively) were localized to 7D chromosome in introgressive lines from crosses between common wheat Triticum aestivum L. and the species Triticum timopheevii Zhuk. Genetic analysis of ten common wheat genotypes using testers carrying genes Pan1, Pn1, and Pn2 showed that these genotypes contained Pan1 and Pn2 genes. Visual examination of plants from 70 and 76 varieties of respectively winter and spring common wheat revealed anthocyanin pigmentation of anthers and culms in 36 varieties. Pan1 and Pn2 genes were presumably introduced into common wheat from Aegilops tauschii (Fig.) Tzvel., a donor of the D genome. PMID:16316016

La?kova, L I; Arbuzova, V S; Efremova, T T; Popova, O M

2005-10-01

103

Charting a Course for Culturally Responsive Physical Education  

Science.gov (United States)

In this article, we explore the absence of understanding related to culturally responsive pedagogy in physical education for Aboriginal students. In so doing, we examine the limited literature related to culturally responsive physical education and the especially limited literature dedicated to Aboriginal students within physical education.…

Robinson, Daniel B.; Borden, Lisa Lunney; Robinson, Ingrid M.

2012-01-01

104

Pollen and Anther Development in Onobrychis schahuensis Bornm.(Fabaceae)  

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Young buds and flowers of Onobrychis schahuensis were removed at different stages of anther development and sectioned with micotome after preparation. The anther and pollen development were studied with light microscopy after staining. Results showed that some ultrastructural characters of anther and pollen grains were different from other Fabaceae members. The undifferentiated anther is ovoid-shaped and tetrasporangiated. The anther wall development follows the dicotyledonous ty...

Abdolkarim Chehregani; Nayereh Tanaomi; Massoud Ranjbar

2008-01-01

105

Cultured articular chondrocytes sheets for partial thickness cartilage defects utilizing temperature-responsive culture dishes  

Directory of Open Access Journals (Sweden)

Full Text Available The extracellular matrix (ECM of articular cartilage has several functions that are unique to joints. Although a technique for transplanting cultured chondrocytes has already been introduced, it is difficult to collect intact ECM when using enzymes to harvest samples. Temperature-responsive culture dishes have already been clinically applied in the fields of myocardial and corneal transplantation. Earlier studies have shown that a sheet of cultured cells with intact ECM and adhesive factors can be harvested using such culture dishes, which allow the surface properties of the dish to be reversibly altered by changing the temperature. Human chondrocytes were subjected to enzymatic digestion and then were seeded in temperature-responsive culture dishes. A sheet of chondrocytes was harvested by only reducing the temperature after the cultured cells reached confluency. A real-time PCR analysis of the chondrocyte sheets confirmed that type II collagen, aggrecan, and fibronectin were present. These results suggested that, although chondrocytes undergo dedifferentiation in a monolayer culture, multilayer chondrocyte sheets grown in a similar environment to that of three-dimensional culture may be able to maintain a normal phenotype. A histological examination suggested that multilayer chondrocyte sheets could thus prevent the loss of proteoglycans because the area covered by the sheets was well stained by safranin-O. The present experiments suggested that temperature-responsive culture dishes are useful for obtaining cultured chondrocytes, which may then be clinically employed as a substitute for periosteal patches because such sheets can be applied without a scaffold.

N Kaneshiro

2007-05-01

106

Culturally Responsive Dance Pedagogy in the Primary Classroom  

Science.gov (United States)

Dance has an important place in multicultural education and the development of culturally responsive pedagogy. Through dance, children can explore and express their own and others' cultures and share their stories in ways other than the spoken and written word. This paper presents a case study concerning a professional development programme in…

Melchior, Elizabeth

2011-01-01

107

Practicing Culturally Responsive Pedagogy in Physical Education  

Science.gov (United States)

As a result of continuous global immigration to the United States, several microcultures coexist within the country. Today's classroom should provide an interface where individuals from different cultural backgrounds have the potential for sharing a rich place of learning--a place where the teacher embraces and celebrates individual differences,…

Young, Shawna; Sternod, Brandon M.

2011-01-01

108

Authoring Professional Teacher Identities: A Journey from Understanding Culturally Responsive Teaching to Identifying as Culturally Responsive Teachers  

Science.gov (United States)

The purpose of this qualitative study was to examine the ways in which four elementary preservice teachers came to understand culturally responsive teaching and began authoring their professional teacher identities. It examined the influence of course work and internship at a culturally and linguistically diverse school on their understandings and…

Tschida, Christina Marie

2009-01-01

109

Transcriptomes of the anther sporophyte: availability and uses.  

Science.gov (United States)

An anther includes sporophytic tissues of three outer cell layers and an innermost layer, the tapetum, which encloses a locule where the gametophytic microspores mature to become pollen. The sporophytic tissues also comprise some vascular cells and specialized cells of the stomium aligning the long anther axis for anther dehiscence. Studies of the anther sporophytic cells, especially the tapetum, have recently expanded from the use of microscopy to molecular biology and transcriptomes. The available sequencing technologies, plus the use of laser microdissection and in silico subtraction, have produced high-quality anther sporophyte transcriptomes of rice, Arabidopsis and maize. These transcriptomes have been used for research discoveries and have potential for future discoveries in diverse areas, including developmental gene activity networking and changes in enzyme and metabolic domains, prediction of protein functions by quantity, secretion, antisense transcript regulation, small RNAs and promoters for generating male sterility. We anticipate that these studies with rice and other transcriptomes will expand to encompass other plants, whose genomes will be sequenced soon, with ever-advancing sequencing technologies. In comprehensive gene activity profiling of the anther sporophyte, studies involving transcriptomes will spearhead investigation of the downstream gene activity with proteomics and metabolomics. PMID:21743085

Huang, Ming-Der; Hsing, Yue-Ie Caroline; Huang, Anthony H C

2011-09-01

110

Faithfulness--Translator’s Responsibility in Cross-Cultural Communication  

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New trends in translation have led to a mistaken notion that faithfulness is obsolete. This article argues that faithfulness should be highlighted in cross-cultural communication to promote better understanding. As a result, a translator should cultivate a strong sense of responsibility, keeping in mind that faithfulness is the guarantee of successful cross-cultural communication. Erroneous translation, either because of incautious, incompetent translation ending in misinformation, or because...

Wu, Feng; Xu, Xihua

2014-01-01

111

Faithfulness--Translator’s Responsibility in Cross-Cultural Communication  

Directory of Open Access Journals (Sweden)

Full Text Available New trends in translation have led to a mistaken notion that faithfulness is obsolete. This article argues that faithfulness should be highlighted in cross-cultural communication to promote better understanding. As a result, a translator should cultivate a strong sense of responsibility, keeping in mind that faithfulness is the guarantee of successful cross-cultural communication. Erroneous translation, either because of incautious, incompetent translation ending in misinformation, or because of deliberate reading into the source language text the translator’s own ideas, ending in disinformation, is detrimental to effective cross-cultural communication. Faithful translation can never be overemphasized.

Feng WU

2014-06-01

112

Unresolved issues in pre-meiotic anther development.  

Science.gov (United States)

Compared to the diversity of other floral organs, the steps in anther ontogeny, final cell types, and overall organ shape are remarkably conserved among Angiosperms. Defects in pre-meiotic anthers that alter cellular composition or function typically result in male-sterility. Given the ease of identifying male-sterile mutants, dozens of genes with key roles in early anther development have been identified and cloned in model species, ordered by time of action and spatiotemporal expression, and used to propose explanatory models for critical steps in cell fate specification. Despite rapid progress, fundamental issues in anther development remain unresolved, and it is unclear if insights from one species can be applied to others. Here we construct a comparison of Arabidopsis, rice, and maize immature anthers to pinpoint distinctions in developmental pace. We analyze the mechanisms by which archesporial (pre-meiotic) cells are specified distinct from the soma, discuss what constitutes meiotic preparation, and review what is known about the secondary parietal layer and its terminal periclinal division that generates the tapetal and middle layers. Finally, roles for small RNAs are examined, focusing on the grass-specific phasiRNAs. PMID:25101101

Kelliher, Timothy; Egger, Rachel L; Zhang, Han; Walbot, Virginia

2014-01-01

113

A culturally responsive counter-narrative of effective teaching  

Science.gov (United States)

How do you recognize an effective teacher's sociocultural consciousness? Tamara Wallace's and Brenda Brand's argument that sociocultural consciousness is the "brain" of effective culturally responsive instruction for students of color comes at a time when the system of teacher evaluation is being overhauled nationwide. Teacher observation tools are being piloted to develop a common language of effective instruction but often there is little attention given to sociocultural consciousness in these frameworks. This article develops a culturally responsive counter-narrative to explore the complexity of a teacher's racial consciousness during a teaching episode.

Gist, Conra D.

2014-12-01

114

A culturally responsive counter-narrative of effective teaching  

Science.gov (United States)

How do you recognize an effective teacher's sociocultural consciousness? Tamara Wallace's and Brenda Brand's argument that sociocultural consciousness is the "brain" of effective culturally responsive instruction for students of color comes at a time when the system of teacher evaluation is being overhauled nationwide. Teacher observation tools are being piloted to develop a common language of effective instruction but often there is little attention given to sociocultural consciousness in these frameworks. This article develops a culturally responsive counter-narrative to explore the complexity of a teacher's racial consciousness during a teaching episode.

Gist, Conra D.

2014-02-01

115

Plant regeneration from hypocotyl- and anther-derived callus of berseem clover. [Trifolium alexandrium  

Energy Technology Data Exchange (ETDEWEB)

Plants were regenerated from hypocotyl and anther explants of berseem clover (Trifolium alexandrinum L.) on Murashige and Skoog (MS) medium containing various combinations of plant growth regulators. The most efficient production of plants from hypocotyl explants involved: callus induction on MS medium with 1.0 mg/liter of naphthaleneacetic acid (NAA) and 1.5 mg/liter 6-furfurylaminopurine (KIN); callus increase on MS medium with 2.0 mg/liter of NAA and 0.1 mg/liter of N/sup 6/-(..delta../sup 2/-isopentenyl) adenine (2iP); induction of shoots on MS medium with 0.5 mg/liter each of NAA and KIN followed by induction of roots on MS medium with 1.0 mg/liter of indoleacetic acid (IAA) and 0.1 mg/liter of 6-benzylaminopurine (BAP). Suspension cultures in liquid MS medium containing 2.0 mg/liter of NAA and 0.2 mg/liter of 2iP provided filterable cell preparations with 45% viable cells, 4% of which gave rise to colonies within 3 weeks after transfer to agar plates. Shoot development was observed when callus from the colonies was cultured on MS medium with 0.5 mg/liter of NAA and KIN. Preliminary results indicate that cells of root tips from hypocotyl- and anther-derived callus have the expected diploid and haploid number of chromosomes (2n = 16 and n = 8, respectively).

Mokhtarzedeh, A.; Constantin, M.J.

1978-01-01

116

A milestone in the doubled haploid pathway of cassava: a milestone in the doubled haploid pathway of cassava (Manihot esculenta Crantz): cellular and molecular assessment of anther-derived structures.  

Science.gov (United States)

This study was aimed at inducing androgenesis in cultured anthers of cassava (Manihot esculenta Crantz) to develop a protocol for the production of doubled haploids. Microspore reprogramming was induced in cassava by cold or heat stress of anthers. Since the anthers contain both haploid microspores and diploid somatic cells, it was essential to verify the origin of anther-derived calli. The origin of anther-derived calli was assessed by morphological screening followed by histological analysis and flow cytometry (FCM). Additionally, simple sequence repeat (SSR) and amplified fragmented length polymorphism (AFLP) assays were used for the molecular identification of the microspore-derived calli. The study clearly demonstrated the feasibility of producing microspore-derived calli using heat- or cold-pretreated anthers. Histological studies revealed reprogramming of the developmental pathway of microspores by symmetrical division of the nucleus. Flow cytometry analysis revealed different ploidy level cell types including haploids, which confirmed their origin from the microspores. The SSR and AFLP marker assays independently confirmed the histological and FCM results of a haploid origin of the calli at the DNA level. The presence of multicellular microspores in the in vitro system indicated a switch of developmental program, which constitutes a crucial step in the design of protocols for the regeneration of microspore-derived embryos and plants. This is the first detailed report of calli, embryos, and abnormal shoots originated from the haploid cells in cassava, leading to the development of a protocol for the production of doubled haploid plants in cassava. PMID:24026343

Perera, P I P; Ordoñez, C A; Lopez-Lavalle, L A Becerra; Dedicova, B

2014-01-01

117

Preparing teachers for ambitious and culturally responsive science teaching  

Science.gov (United States)

Communities, schools and classrooms across North America are becoming more ethnically, racially, and linguistically diverse, particularly in urban areas. Against this backdrop, underrepresentation of certain groups in science continues. Much attention has been devoted to multicultural education and the preparation of teachers for student diversity. In science education, much research has focused on classrooms as cultural spaces and the need for teachers to value and build upon students' everyday science knowledge and ways of sense-making. However it remains unclear how best to prepare science teachers for this kind of culturally responsive teaching. In attempting to envision how to prepare science teachers with cross-cultural competency, we can draw from a parallel line of research on preparing teachers for ambitious science instruction. In ambitious science instruction, students solve authentic problems and generate evidence and models to develop explanations of scientific phenomenon, an approach that necessitates great attention to students' thinking and sense-making, thus making it applicable to cultural relevance aims. In addition, this line of research on teacher preparation has developed specific tools and engages teachers in cycles of reflection and rehearsal as they develop instructional skills. While not addressing cross-cultural teaching specifically, this research provides insights into specific ways through which to prepare teachers for culturally responsive practices. In my presentation, I will report on efforts to join these two areas of research, that is, to combine ideas about multicultural science teacher preparation with what has been learned about how to develop ambitious science instruction. This research suggests a new model for urban science teacher preparation---one that focuses on developing specific teaching practices that elicit and build on student thinking, and doing so through cycles of individual and collective planning, rehearsal, review, and reflection. In this way, a defined set of science-specific, ambitious and culturally responsive instructional practices can be articulated and taught during science teacher preparation.

Seiler, Gale

2013-03-01

118

Culturally Responsive Teaching for American Indian Students. ERIC Digest.  

Science.gov (United States)

Culturally responsive teaching cannot be approached as a recipe or series of steps that teachers can follow to become effective with American Indian and Alaska Native (AI/AN) students. Instead, it relies on the development of certain dispositions toward learners and a holistic approach to curriculum and instruction. This digest draws on a…

Pewewardy, Cornel; Hammer, Patricia Cahape

119

Universities' Responses to Globalisation: The Influence of Organisational Culture  

Science.gov (United States)

This study sought to assess how and why some higher education institutions have responded to aspects of globalisation and, in particular how organisational culture influences universities' responses to globalisation. Using a predominantly qualitative, mixed-methods approach, empirical research was used to explore the impact of globalisation at…

Burnett, Sally-Ann; Huisman, Jeroen

2010-01-01

120

The Magic of Culturally Responsive Pedagogy: In Search of the Genie's Lamp in Multicultural Education.  

Science.gov (United States)

In recent years, there has been growing interest in helping teachers develop culturally responsive teaching strategies. This paper profiles crucial aspects of a culturally responsive pedagogy and proposes a holistic framework for integrating different levels of culture into culturally responsive teaching. A literature review examined 13 documents…

Phuntsog, Nawang

 
 
 
 
121

Rat Sertoli cells acquire a ?-adrenergic response during primary culture  

International Nuclear Information System (INIS)

Two-dimensional polyacrylamide gel electrophoresis and the radioligand (-)-[125I]iodopindolol (125I-Pin) have been used to study isoproterenol-dependent protein phosphorylation and ?-adrenergic receptor availability, respectively, in cultured Sertoli cells and freshly isolated seminiferous tubular segments of sexually immature and mature rats. Sertoli cells prepared from sexually immature rats show progressive 125I-Pin binding in primary cultures that correlates with isoproterenol-induced cell shape changes, redistribution of immunoreactive vimentin, and phosphorylation of this intermediate filament protein. Seminiferous tubules do not show significant isoproterenol-dependent vimentin phosphorylation nor 125I-Pin binding. However, vimentin phosphorylation can be induced by follicle-stimulating hormone or a cyclic nucleotide analog. This study stresses the need for correlating pharmacological-induced responses observed in Sertoli cell primary cultures with those in the intact seminiferous tubule

122

Fine Division of Rice Anther Development by Cytological Morphology  

Directory of Open Access Journals (Sweden)

Full Text Available A cytological and morphological study was conducted on the anther of a hybrid rice (Oryza Sativa L. indica strain, Chuan You 9527. To sutdy the growth procedures of pollen and anther wall, their development processes from stamen primordia initiation to pollen maturation were observed and divided into stages. Rice spikelets ranging from approx. 1.0 millimeter to approx. 10.0 millimeter were chosen; loading films of anthers were prepared by using the techniques of paraffin section, and they were observed and then photographed with digital camera system for optical microscopy (Nikon DS-Ril-U2. The results showed that the whole development process of anther could be divided into thirteen fine stages, based on the significant alterations in the morphological characteristics of cells and tissues. The thirteen stages are archesporial cell stage, bi-parietal stage, tri-parietal stage, pollen mother cell forming stage (the above four stages together are known as microsporocyte forming stage, early pollen mother cell meiosis stage, mid pollen mother cell meiosis stage, pollen mother cell dayad stage, pollen mother cell tetrad stage( the above four stages are known collectively as microsporocyte meiosis stage, early microspore stage, mid microspore stage, late microspore stage, bi-cellular pollen stage, and mature pollen stage.

LI Gui-jie

2011-05-01

123

Early anther ablation triggers parthenocarpic fruit development in tomato.  

Science.gov (United States)

Fruit set and fruit development in tomato is largely affected by changes in environmental conditions, therefore autonomous fruit set independent of fertilization is a highly desirable trait in tomato. Here, we report the production and characterization of male-sterile transgenic plants that produce parthenocarpic fruits in two tomato cultivars (Micro-Tom and Moneymaker). We generated male-sterility using the cytotoxic gene barnase targeted to the anthers with the PsEND1 anther-specific promoter. The ovaries of these plants grew in the absence of fertilization producing seedless, parthenocarpic fruits. Early anther ablation is essential to trigger the developing of the transgenic ovaries into fruits, in the absence of the signals usually generated during pollination and fertilization. Ovaries are fully functional and can be manually pollinated to obtain seeds. The transgenic plants obtained in the commercial cultivar Moneymaker show that the parthenocarpic development of the fruit does not have negative consequences in fruit quality. Throughout metabolomic analyses of the tomato fruits, we have identified two elite lines which showed increased levels of several health promoting metabolites and volatile compounds. Thus, early anther ablation can be considered a useful tool to promote fruit set and to obtain seedless and good quality fruits in tomato plants. These plants are also useful parental lines to be used in hybrid breeding approaches. PMID:23581527

Medina, Mónica; Roque, Edelín; Pineda, Benito; Cañas, Luis; Rodriguez-Concepción, Manuel; Beltrán, José Pío; Gómez-Mena, Concepción

2013-08-01

124

Cytotoxic responses of selected insecticides in chick ganglia cultures.  

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Various agricultural chemicals, e.g. pesticides, are known to cause different toxic effects in man and animals. Some of these produce responses involving the nervous tissue. Total of 52 such chemicals, representing organophosphates, carbamates and other miscellaneous insecticides were evaluated to determine their relative cytotoxic effects in avian dorsal root ganglia cultures. Many of these chemicals caused a slight stimulation of cellular growth at very low concentrations. At toxic concentr...

Sharma, R. P.; Obersteiner, E. J.

1981-01-01

125

Beyond self-assessment--assessing organizational cultural responsiveness.  

Science.gov (United States)

While there is growing recognition of the need for health care organizations to provide culturally responsive care, appropriate strategies for assessing organizational responsiveness have not been determined. A document review assessment instrument was designed to assess best practice within eight domains, and along seven dimensions of organizational approach to diversity. Results obtained from the pilot of the instrument were congruent with data collected from key informant interviews, a focus group, observational methods and organizational feedback session; however, they were not consistent with self-assessment results at the same site. A larger pilot is required to determine generalizability of results. PMID:19172974

Bowen, Sarah

2008-01-01

126

Desempenho de linhagens diaplóides de trigo obtidas via cultura de anteras quanto à tolerância ao alumínio, produção de grãos e altura de planta / Performance of dihaploid wheat lines obtained via anther culture in relation to the aluminum tolerance, grain yield and plant height  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Avaliaram-se 18 linhagens diaplóides de trigo, obtidas via cultura de anteras in vitro oriundas de híbridos F1, e dois cultivares IAC-24 e IAC-289, nos anos de 1999 e 2000, em dois locais do Estado de São Paulo: Capão Bonito (solo ácido, sem aplicação de calcário e em condição de sequeiro) e em Tatu [...] í (solo ácido, com aplicação de calcário e em condição de irrigação por aspersão). Em cada experimento avaliaram-se a produção de grãos e a altura das plantas. Foi, também, avaliada a tolerância à toxicidade de alumínio, empregando-se soluções nutritivas contendo 0, 2, 4, 6, 8 e 10 mg.L-1, em condição de laboratório. As linhagens diaplóides consideradas mostraram grande variabilidade para os caracteres agronômicos avaliados. Destacaram-se quanto à produção de grãos, considerando a média dos experimentos de Capão Bonito, as linhagens 9 (MRL"S"/BUC"S"//BUC"S"/3/ IAC-24), 4 (PF70402/ALD"S"//PAT72160/ALD"S" /3/PEW"S"/4/OPATA/5/IAC-60) e 3 (TEPOCA/IAC-24). Em Tatuí, considerando-se a média dos dois anos, destacaram-se quanto à produção de grãos as linhagens 4 e 5, oriundas do mesmo cruzamento. A linhagem 13 (JUN/GEN//IAC-24) apresentou as plantas mais baixas nos quatro experimentos. Todos os genótipos, com exceção da cultivar IAC-289 e da linhagem 13, foram considerados tolerantes a 10 mg.L-1 de Al3+, quando avaliados em soluções nutritivas. Os resultados reforçam a possibilidade de selecionar os genótipos tolerantes ao alumínio, em condição de laboratório, antes que sejam avaliados em campo, em solo ácido, tornando o processo de obtenção de linhagens tolerantes mais eficiente. Abstract in english Eighteen dihaploid wheat lines originated via anther culture from F1 hybrid plants and two cultivars IAC-24 and IAC-289 were evaluated in 1999 and 2000, at two locations of the State of São Paulo: Capão Bonito (acid soil without lime application and upland condition) and Tatuí (acid soil with lime a [...] pplication and sprinkler irrigation condition). In each trial the genotypes were evaluated for grain yield and plant height. Aluminum toxicity tolerance was also evaluated in the laboratory in nutrient solutions containing 0, 2, 4, 6, 8 and 10 mg.L-1 of aluminum. The evaluated dihaploid lines showed high variability for the considered agronomic characters. The lines 9 (MRL"S"/BUC"S"//BUC"S"/3/IAC-24), 4 (PF70402/ ALD"S"//PAT72160/ALD"S"/3/PEW"S"/4/OPATA/5/IAC-60) and 3 (TEPOCA/IAC-24) displayed good performance in relation to grain yield considering the means of the Capão Bonito trials. In Tatuí the lines 4 and 5 originated from the same cross showed good behaviour for grain yield taking into account the means of the trials. The line 13 (JUN/GEN//IAC-24) exhibited short plants in all trials. All genotypes, except the cultivar IAC-289 and the line 13 were considered tolerant at 10 mg.L-1 to Al3+, in nutrient solution. The results indicated the possibility to select tolerant genotypes to aluminum toxicity in laboratory condition before they are evaluated in acid soil, making the process of obtaining tolerant lines more efficient.

Marcus Vinicius, Salomon; Carlos Eduardo de Oliveira, Camargo; Antonio Wilson Penteado, Ferreira Filho; Armando, Pettinelli Júnior; Jairo Lopes de, Castro.

127

Expressed sequences tags of the anther smut fungus, Microbotryum violaceum, identify mating and pathogenicity genes  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background The basidiomycete fungus Microbotryum violaceum is responsible for the anther-smut disease in many plants of the Caryophyllaceae family and is a model in genetics and evolutionary biology. Infection is initiated by dikaryotic hyphae produced after the conjugation of two haploid sporidia of opposite mating type. This study describes M. violaceum ESTs corresponding to nuclear genes expressed during conjugation and early hyphal production. Results A normalized cDNA library generated 24,128 sequences, which were assembled into 7,765 unique genes; 25.2% of them displayed significant similarity to annotated proteins from other organisms, 74.3% a weak similarity to the same set of known proteins, and 0.5% were orphans. We identified putative pheromone receptors and genes that in other fungi are involved in the mating process. We also identified many sequences similar to genes known to be involved in pathogenicity in other fungi. The M. violaceum EST database, MICROBASE, is available on the Web and provides access to the sequences, assembled contigs, annotations and programs to compare similarities against MICROBASE. Conclusion This study provides a basis for cloning the mating type locus, for further investigation of pathogenicity genes in the anther smut fungi, and for comparative genomics.

Devier Benjamin

2007-08-01

128

Activity of carbon dioxide fixation by anthers and leaves of cereal grains  

International Nuclear Information System (INIS)

This paper gives a comparative evaluation of the photosynthetic activity of anthers and flag leaves in winter wheat, rye, and triticale. The content of chlorophylls in anthers and leaves was determined. The activity of 14CO2 fixation by anthers and leaf disks was determined by the radiometric method in a chamber floating on mercury under standard exposure conditions (0.1% concentration of 14CO2, illumination of 15,000 1x, temperature of 23 C). Analyses were conducted in three replications and the results of typical biological experiments are cited. Data show that chlorophyll is actively synthesized in the anthers of cereal grains

129

Differentiation of cultured epithelial cells: Response to toxic agents  

Energy Technology Data Exchange (ETDEWEB)

Cell culture systems are instrumental in elucidating regulation of normal function and mechanisms of its perturbation by toxic substances. To this end, three applications of epithelial cells cultured with 3T3 feeder layer support are described. First, treatment of the premalignant human epidermal keratinocyte line SCC-12F2 with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate suppressed cell growth and differentiation. This agent produced a biphasic growth response greatly inhibiting cell growth at 1 to 10 nM, but much less above 100 nM. Expression of the differentiated functions involucrin and transglutaminase was found to be inhibited markedly at concentrations above 10 nM. Second, 3-methylcholanthrene toxicity was surveyed in a variety of rat epithelial cell types. The two most sensitive to growth inhibition were epidermal and mammary epithelial cells, while those from bladder, prostate, thyroid, and endometrium were insensitive to growth inhibition. Finally, expression of estrogen receptors in rat endometrial cells was shown to be stimulated by the cAmP-elevating agent forskolin. Maximal stimulation of 3- to 6-fold occurred in 6 hr, compatible with a requirement for protein synthesis. Pursuit of such results will aid in understanding differences in response among cell types and species, in elucidating mechanisms of action of known toxic substances and, ultimately, in predicting toxicity of less well understood agents.

Rice, R.H.; LaMontagne, A.D.; Petito, C.T.; Rong, Xianhui (Charles A. Dana Laboratory of Toxicology, Boston, MA (USA))

1989-03-01

130

A novel lily anther-specific gene encodes adhesin-like proteins associated with exine formation during anther development.  

Science.gov (United States)

The anther-specific gene LLA1271 isolated from lily (Lilium longiflorum Thunb.) anthers is novel and exists in two forms. The protein encoded by LLA1271 may represent an adhesin-like protein first found in higher plants. The protein contains a typical N-terminal signal peptide followed by a highly conserved repeat domain. The LLA1271 gene is temporally expressed at the phase of microspore development. RNA blot and RNA in situ hybridization analyses demonstrated that the gene was expressed both in the tapetum and in the microspore. The gene is endo- and exogenously induced by gibberellin. Studies with the gibberellin biosynthesis inhibitor uniconazole and an inhibitor of ethylene activity, 2,5-norbornadien (NBD), revealed that LLA1271 is negatively regulated by ethylene, and a cross-talk of regulation between gibberellin and ethylene occurs in young anthers. The treatment with NBD caused the tapetum to become densely cytoplasmic and highly polarized, whereas uniconazole arrested tapetal development in a state close to that of a tapetum without treatment. The LLA1271 protein is heat stable and heterogeneous. An immunoblot of separated protein fractions of the anther revealed that the LLA1271 protein was detected in protein fraction of the microspore released from the cell wall by treatment with either 0.5% or 2% Triton X-100. Ectopic expression of LLA1271 resulted in impaired stamen and low pollen germination. Scanning electron microscopy of TAP::LLA1271 pollen showed distorted exine formation and patterning. The LLA1271 protein once synthesized in both the tapetum and microspore is secreted and deposited on the surface of microspores, moderately affecting exine formation and patterning. PMID:24591055

Liu, Ming-Che; Yang, Cheng-Shou; Yeh, Fang-Ling; Wei, Chi-Hsuan; Jane, Wann-Neng; Chung, Mei-Chu; Wang, Co-Shine

2014-05-01

131

Hemopoietic cell precursor responses to erythropoietin in plasma clot cultures  

Energy Technology Data Exchange (ETDEWEB)

The time dependence of the response of mouse bone marrow cells to erythropoietin (Ep) in vitro was studied. Experiments include studies on the Ep response of marrow cells from normal, plethoric, or bled mice. Results with normal marrow reveal: (1) Not all erythroid precursors (CFU-E) are alike in their response to Ep. A significant number of the precursors develop to a mature erythroid colony after very short Ep exposures, but they account for only approx. 13% of the total colonies generated when Ep is active for 48 hrs. If Ep is active more than 6 hrs, a second population of erythroid colonies emerges at a nearly constant rate until the end of the culture. Full erythroid colony production requires prolonged exposure to erythropoietin. (2) The longer erythropoietin is actively present, the larger the number of erythroid colonies that reach 17 cells or more. Two distinct populations of immediate erythroid precursors are also present in marrow from plethoric mice. In these mice, total colony numbers are equal to or below those obtained from normal mice. However, the population of fast-responding CFU-E is consistently decreased to 10 to 20% of that found in normal marrow. The remaining colonies are formed from plethoric marrow at a rate equal to normal marrow. With increasing Ep exposures, the number of large colonies produced increases. From the marrow of bled mice, total erythroid colony production is equal to or above that of normal marrow. Two populations of colony-forming cells are again evident, with the fast-responding CFU-E being below normal levels. The lack of colonies from this group was compensated in bled mice by rapid colony production in the second population. A real increase in numbers of precursors present in this pool increased the rate of colony production in culture to twice that of normal marrow. The number of large colonies obtained from bled mice was again increased as the Ep exposure was lengthened. (ERB)

Kennedy, W.L.

1979-01-01

132

Analysis of biochemical characteristics of maize anthers from male fertilizable plant and male sterile plant induced by space flight  

International Nuclear Information System (INIS)

The contents of soluble sugar, starch, protein and free praline in anthers were analyzed and compared between male fertilizable and male sterile induced by space flight at different developmental stages. The results showed that all contents were lower in male sterile anthers than in fertilisable ones. With anther developing, the contents of soluble starch, protein and free proline increased obviously in male fertilizable anthers, but not in sterile ones. (authors)

133

The NAC-like gene ANTHER INDEHISCENCE FACTOR acts as a repressor that controls anther dehiscence by regulating genes in the jasmonate biosynthesis pathway in Arabidopsis.  

Science.gov (United States)

ANTHER INDEHISCENCE FACTOR (AIF), a NAC-like gene, was identified in Arabidopsis. In AIF:GUS flowers, ?-glucuronidase (GUS) activity was detected in the anther, the upper parts of the filaments, and in the pollen of stage 7-9 young flower buds; GUS activity was reduced in mature flowers. Yellow fluorescent protein (YFP)+AIF-C fusion proteins, which lacked a transmembrane domain, accumulated in the nuclei of the Arabidopsis cells, whereas the YFP+AIF fusion proteins accumulated in the membrane and were absent in the nuclei. Further detection of a cleaved AIF protein in flowers revealed that AIF needs to be processed and released from the endoplasmic reticulum in order to function. The ectopic expression of AIF-C caused a male-sterile phenotype with indehiscent anthers throughout flower development in Arabidopsis. The presence of a repressor domain in AIF and the similar phenotype of indehiscent anthers in AIF-C+SRDX plants suggest that AIF acts as a repressor. The defect in anther dehiscence was due to the down-regulation of genes that participate in jasmonic acid (JA) biosynthesis, such as DAD1/AOS/AOC3/OPR3/OPCL1. The external application of JA rescued the anther indehiscence in AIF-C and AIF-C+SRDX flowers. In AIF-C+VP16 plants, which are transgenic dominant-negative mutants in which AIF is converted to a potent activator via fusion to a VP16-AD motif, the anther dehiscence was promoted, and the expression of DAD1/AOS/AOC3/OPR3/OPCL1 was up-regulated. Furthermore, the suppression of AIF through an antisense strategy resulted in a mutant phenotype similar to that observed in the AIF-C+VP16 flowers. The present data suggest a role for AIF in controlling anther dehiscence by suppressing the expression of JA biosynthesis genes in Arabidopsis. PMID:24323506

Shih, Ching-Fang; Hsu, Wei-Han; Peng, Yan-Jhu; Yang, Chang-Hsien

2014-02-01

134

What We Know about Culturally Responsive Instruction. Information Capsule. Volume 0606  

Science.gov (United States)

All children grow up within a cultural environment that influences their learning patterns and communication styles and how they interpret experiences, process and organize information, and perceive their surroundings. Culturally responsive instruction incorporates students' cultures and experiences into the classroom curriculum and uses their…

Blazer, Christie

2007-01-01

135

Successful development of a shed-microspore culture protocol for doubled haploid production in Indonesian hot pepper (Capsicum annuum L.)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Various systems of anther and microspore cultures were studied to establish an efficient doubled haploid production method for Indonesian hot pepper (Capsicum annuum L.). A shed-microspore culture protocol was developed which outperformed all the previously reported methods of haploid production in pepper. The critical factors of the protocol are: selection of flower buds with more than 50% late unicellular microspores, a 1 day 4°C pretreatment of the buds, followed by culture of the anthers...

Supena, E. D. J.; Suharsono, S.; Jacobsen, E.; Custers, J. B. M.

2006-01-01

136

"Because That's Who I Am": Extending Theories of Culturally Responsive Pedagogy to Consider Religious Identity, Belief, and Practice  

Science.gov (United States)

In this conceptual article the author explores the intersection of culturally responsive pedagogy and religious school contexts. He extends theories of culturally responsive pedagogy to consider how religion, a dimension of student culture that has largely been overlooked in the literature surrounding culturally responsive pedagogy, can inflect…

Dallavis, Christian

2011-01-01

137

Culturally responsive health promotion in puerto rican communities: a structuralist approach.  

Science.gov (United States)

This literature review discusses the value of the structuralist approach as an integrated theoretical and methodological framework for participatory cultural assessments designed to capture the cultural dynamics of those affected by health disparities. Drawing from principles of the Lévi-Straussian strand of structural anthropology found in contemporary cultural studies, and using the Puerto Rican cultural experience as an example, the authors present the distinction between deep and surface structures of cultural knowledge and meaning and highlight information-processing and behavioral systems influenced by the complexity of cognitive and social representations of cultural structures. To understand and address the deeply rooted web of ideology, norms, and practices that influence health decision making and behavioral responses, the authors show the need for ethnographic narrative inquiry beyond surface manifestations of culture. Finally, the authors discuss the implications of the structuralist approach for culturally responsive health education and other health promotion interventions. PMID:18340090

Idalí Torres, María; Marquez, David X; Carbone, Elena T; Stacciarini, Jeanne-Marie R; Foster, Jennifer W

2008-04-01

138

Glacial refugia in pathogens: European genetic structure of anther smut pathogens on Silene latifolia and Silene dioica.  

Science.gov (United States)

Climate warming is predicted to increase the frequency of invasions by pathogens and to cause the large-scale redistribution of native host species, with dramatic consequences on the health of domesticated and wild populations of plants and animals. The study of historic range shifts in response to climate change, such as during interglacial cycles, can help in the prediction of the routes and dynamics of infectious diseases during the impending ecosystem changes. Here we studied the population structure in Europe of two Microbotryum species causing anther smut disease on the plants Silene latifolia and Silene dioica. Clustering analyses revealed the existence of genetically distinct groups for the pathogen on S. latifolia, providing a clear-cut example of European phylogeography reflecting recolonization from southern refugia after glaciation. The pathogen genetic structure was congruent with the genetic structure of its host species S. latifolia, suggesting dependence of the migration pathway of the anther smut fungus on its host. The fungus, however, appeared to have persisted in more numerous and smaller refugia than its host and to have experienced fewer events of large-scale dispersal. The anther smut pathogen on S. dioica also showed a strong phylogeographic structure that might be related to more northern glacial refugia. Differences in host ecology probably played a role in these differences in the pathogen population structure. Very high selfing rates were inferred in both fungal species, explaining the low levels of admixture between the genetic clusters. The systems studied here indicate that migration patterns caused by climate change can be expected to include pathogen invasions that follow the redistribution of their host species at continental scales, but also that the recolonization by pathogens is not simply a mirror of their hosts, even for obligate biotrophs, and that the ecology of hosts and pathogen mating systems likely affects recolonization patterns. PMID:21187901

Vercken, Elodie; Fontaine, Michael C; Gladieux, Pierre; Hood, Michael E; Jonot, Odile; Giraud, Tatiana

2010-01-01

139

Using Culturally Competent Responsive Services to Improve Student Achievement and Behavior  

Science.gov (United States)

This article illustrates standards blending, the integration of core academic and school counseling standards, as a culturally alert responsive services strategy to assist in closing the achievement gap while also enhancing employability skills and culturally salient career competencies. The responsive services intervention described in this…

Schellenberg, Rita; Grothaus, Tim

2011-01-01

140

Qualifying Sociopolitical Consciousness: Complicating Culturally Responsive Pedagogy for Faith-Based Schools  

Science.gov (United States)

This article explores the intersection of culturally responsive pedagogy and faith-based schooling. The author presents a portion of a larger ethnographic research project conducted at a Catholic elementary school that serves a predominantly Latino population in urban Chicago. This work contributes to theories of culturally responsive education by…

Dallavis, Christian

2013-01-01

 
 
 
 
141

Culturable bacteria in Himalayan ice in response to atmospheric circulation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Only recently has specific attention been given to culturable bacteria in Tibetan glaciers, but their relation to atmospheric circulation is less understood yet. Here we investigate the seasonal variation of culturable bacteria preserved in a Himalayan ice core. High concentration of culturable bacteria in glacial ice deposited during the pre-monsoon season is attributed to the transportation of continental dust stirred up by the frequent dust storms in Northwest China during spring. This is ...

Zhang, S.; Hou, S.; Ma, X.; Qin, D.; Chen, T.

2006-01-01

142

Calogênese in vitro em anteras de coffea arabica L. In vitro callogenesis in anthers of Coffea arabica L.  

Directory of Open Access Journals (Sweden)

Full Text Available O café é um dos mais importantes produtos do mercado internacional; porém, o tempo gasto e os recursos despendidos são fatores limitantes para o melhoramento do cafeeiro por meio de métodos convencionais. Contudo, a cultura de anteras surge como uma alternativa viável e de curto prazo para solução desses problemas. Com o presente trabalho, objetivou-se a produção de dihaplóides com a cultura de anteras do cafeeiro (androgênese indireta, buscando um protocolo para a fase de indução de calos. Para tanto, foi efetuada a assepsia dos botões florais e das anteras, que, em seguida, foram inoculadas em meio IC e mantidas no escuro por 8 semanas, sob temperatura de 25ºC ± 1. Para induzir a calogênese em anteras da cv. Acaiá Cerrado, foram testadas as concentrações de 2,4-D (0, 1, 2 e 4 mg.L-1 x cinetina (0, 2, 4 e 8 mg.L-1 e 2,4-D (0; 0,5; 1 e 2 mg.L-1 x AIB (0; 0,5; 1 e 2 mg.L-1 mais 2iP (2 mg.L-1 e, para a cv. Rubi, as concentrações de 2,4-D (0, 1, 2 e 4 mg.L-1 x cinetina (0, 2, 4 e 8 mg.L-1. Foi observado que a maior porcentagem de indução de calogênese em anteras na cv. Acaiá Cerrado ocorre com as combinações de 2,4-D (2 mg.L-1 + cinetina (1,9 mg.L-1 e 2,4-D (0,86 mg.L-1 + AIB (1 mg.L-1+ 2iP (2 mg.L-1; para cv. Rubi, a combinação de 2,4-D (1,9 mg.L-1 e cinetina (4 mg.L-1.The coffee is one of the most important products of the international market, however the time and money wasted in breeding programs are limiting factors for its improvement. However, the anther culture appears as a viable alternative for a short time period solution for this problem. This work aimed to obtain the double haploids production from anther cultures of the coffee plant (indirect androgenesis aiming to optimize a protocol calluse induction. For this purpose, asseptic conditions of the flower budsand anthers were accomplished, folowed by inoculationin IC medium and the tissue were kept for eight weeks at 25ºC ± 1 in the dark. To induce callogenesis in anthers of the 'Acaiá Cerrado' there were tested 2,4-D (0, 1, 2 and 4 mg.L-1 x kinetin (0, 2, 4 and 8 mg.L-1 and 2,4-D (0; 0,5; 1 and 2mg.L-1 x AIB (0; 0,5; 1 and 2mg.-1 plus 2 iP (2 mg.L-1 concentrations and for the 'Rubi' 2,4-D (0, 1, 2 and 4 mg.L-1 x kinetin (0, 2, 4 and 8 mg.L-1 concentrations. It was observed that the highest percentage of callogenesis induction in anthers of the 'Acaiá Cerrado' was provenient from 2,4-D (2 mg.L-1 + kinetin (1,9 mg.L-1 and 2,4-D (0,86 mg.L-1 + AIB (1 mg.L-1+ 2iP (2mg.L-1 combinations for 'Rubi' 2,4-D (1,9 mg.L-1 and kinetin (4 mg.L-1.

Ednamar Gabriela Palú

2004-08-01

143

Culturable bacteria in Himalayan ice in response to atmospheric circulation  

Directory of Open Access Journals (Sweden)

Full Text Available Only recently has specific attention been given to culturable bacteria in Tibetan glaciers, but their relation to atmospheric circulation is less understood yet. Here we investigate the seasonal variation of culturable bacteria preserved in a Himalayan ice core. High concentration of culturable bacteria in glacial ice deposited during the pre-monsoon season is attributed to the transportation of continental dust stirred up by the frequent dust storms in Northwest China during spring. This is also confirmed by the spatial distribution of culturable bacteria in Tibetan glaciers. Culturable bacteria deposited during monsoon season are more diverse than other seasons because they derive from both marine air masses and local or regional continental sources. We suggest that microorganisms in Himalayan ice can be used to reconstruct atmospheric circulation.

S. Zhang

2006-06-01

144

In vitro seed germination and calli induction in seedlings, cotyledons and anthers of bottle gourd (Lagenaria siceraria (Mol. Stand. - Cucurbitaceae  

Directory of Open Access Journals (Sweden)

Full Text Available The bottle gourd has economial importance for small and medium farms and great potential for industrial applications. Different strategies were tested for the in vitro seed germination, as luminosity, scarification, imbibition and addition of ANA (naftalenoacetic acid and 2,4-D (2,4-Dichlorophenoxyacetic acid on the culture medium. Later on, nodal segments and shoot tips were cultivated on medium supplemented with Fuji vitamins and cotyledonary explants cultivated in different concentrations of BAP (6-Benzylaminopurine and ANA. For the calli induction, anthers were cultivated on medium contending 2,4-D and BAP. The germination of bottle gourd seeds occurred in the light and in the darkness, indicating neutral photoblastism. The scarification and the imbibition of whole seeds (seeds with tegument did not facilitate the germination, in none of the treatments. ANA and 2,4-D in the variation of 0.12-1.0 mg.L-1 do not allow the in vitro germination of whole seeds on the culture medium. ANA and 2,4-D in the concentrations of 0.5 mg.L-1 and 0.25 mg.L-1, respectively, increased the in in vitro germination of nude seeds (seeds without tegument of bottle gourd. The supplementation with Fuji vitamins allows the calli formation, mainly in the nodal segments. The calli formation in anthers (obtained from floral buttons contends 0.9 cm length occurs on MS culture medium supplemented with 0.5 and 1.0 mg.L-1 of 2,4-D and BAP

Sergio Augusto Oliveira Alves

2012-01-01

145

Emergence and patterning of the five cell types of the Zea mays anther locule.  

Science.gov (United States)

One fundamental difference between plants and animals is the existence of a germ-line in animals and its absence in plants. In flowering plants, the sexual organs (stamens and carpels) are composed almost entirely of somatic cells, a small subset of which switch to meiosis; however, the mechanism of meiotic cell fate acquisition is a long-standing botanical mystery. In the maize (Zea mays) anther microsporangium, the somatic tissues consist of four concentric cell layers that surround and support reproductive cells as they progress through meiosis and pollen maturation. Male sterility, defined as the absence of viable pollen, is a common phenotype in flowering plants, and many male sterile mutants have defects in somatic and reproductive cell fate acquisition. However, without a robust model of anther cell fate acquisition based on careful observation of wild-type anther ontogeny, interpretation of cell fate mutants is limited. To address this, the pattern of cell proliferation, expansion, and differentiation was tracked in three dimensions over 30 days of wild-type (W23) anther development, using anthers stained with propidium iodide (PI) and/or 5-ethynyl-2'-deoxyuridine (EdU) (S-phase label) and imaged by confocal microscopy. The pervading lineage model of anther development claims that new cell layers are generated by coordinated, oriented cell divisions in transient precursor cell types. In reconstructing anther cell division patterns, however, we can only confirm this for the origin of the middle layer (ml) and tapetum, while young anther development appears more complex. We find that each anther cell type undergoes a burst of cell division after specification with a characteristic pattern of both cell expansion and division. Comparisons between two inbreds lines and between ab- and adaxial anther florets indicated near identity: anther development is highly canalized and synchronized. Three classical models of plant organ development are tested and ruled out; however, local clustering of developmental events was identified for several processes, including the first evidence for a direct relationship between the development of ml and tapetal cells. We speculate that small groups of ml and tapetum cells function as a developmental unit dedicated to the development of a single pollen grain. PMID:21070762

Kelliher, Timothy; Walbot, Virginia

2011-02-01

146

Thermo-responsive surfaces for enzyme free mammalian cell culture  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Embryonic stem cells are of great interest to scientists as they can differentiate into any somatic cell lineage making them excellent candidates for tissue regeneration and cell based treatment therapies. Currently, human embryonic stem cells (hESCs) are cultured using feeder fibroblasts or protein substrates such as matrigel, fibronectin or laminin in conditioned media. hESCs are then subcultured using enzymes to detach them from the culture substrate. However, the use of the xenosupport sy...

Dey, Sabrina

2010-01-01

147

Histological aspects of anther Wall in male fertile and cytoplasmic male sterile sunflower - Helianthus annuus L.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this study, development of anther wall of Helianthus annuus L. male fertile HA 89 "B" line and cytoplasmic male sterile HA 89 "A" line were compared by light and electron microscopy. It was observed that there was no difference between male fertile HA 89 "B" line and male sterile HA 89 "A" line development of anther wall until tetrads were formed. After tetrad stage it was observed in ma...

Meric Ciler; Dane Feruzan; Olgun Goksel

2003-01-01

148

Oviposition Attractancy of Bacterial Culture Filtrates: response of Culex quinquefasciatus  

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Full Text Available Oviposition attractants could be used for monitoring as well as controlling mosquitoes by attracting them to lay eggs at chosen sites. In the present study, culture filtrates of seven bacterial species were tested for their attractancy against gravid females of Culex quinquefasciatus. When their oviposition active indices (OAI were studied, the culture filtrates of Bacillus cereus and Pseudomonas fluorescens exhibited oviposition attractancy (OAI = >0.3 at 100 ppm and the OAI were respectively 0.70 and 0.47. Culture filtrates of B. thuringiensis var. israelensis (wild type, B. t. var. israelensis (mutant and B. sphaericus showed attractancy at 2000 ppm with OAI of respectively 0.71, 0.59 and 0.68. However, the OAI of B. megaterium as well as Azospirillum brasilense was 0.13 (at 2000 ppm, which was less than 0.3 required to be considered them as attractants. When the oviposition attractancy of the bacterial culture filtrates were compared with that of a known oviposition attractant, p-cresol (at 10 ppm, the culture filtrates of B. t. var. israelensis (wild type and B. cereus were found to be more active than p-cresol, respectively with 64.2 and 54.3% oviposition.

S Poonam

2002-04-01

149

Oviposition Attractancy of Bacterial Culture Filtrates: response of Culex quinquefasciatus  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Oviposition attractants could be used for monitoring as well as controlling mosquitoes by attracting them to lay eggs at chosen sites. In the present study, culture filtrates of seven bacterial species were tested for their attractancy against gravid females of Culex quinquefasciatus. When their ovi [...] position active indices (OAI) were studied, the culture filtrates of Bacillus cereus and Pseudomonas fluorescens exhibited oviposition attractancy (OAI = >0.3) at 100 ppm and the OAI were respectively 0.70 and 0.47. Culture filtrates of B. thuringiensis var. israelensis (wild type), B. t. var. israelensis (mutant) and B. sphaericus showed attractancy at 2000 ppm with OAI of respectively 0.71, 0.59 and 0.68. However, the OAI of B. megaterium as well as Azospirillum brasilense was 0.13 (at 2000 ppm), which was less than 0.3 required to be considered them as attractants. When the oviposition attractancy of the bacterial culture filtrates were compared with that of a known oviposition attractant, p-cresol (at 10 ppm), the culture filtrates of B. t. var. israelensis (wild type) and B. cereus were found to be more active than p-cresol, respectively with 64.2 and 54.3% oviposition.

S, Poonam; KP, Paily; K, Balaraman.

2002-04-01

150

The Cultural Responsiveness of Teacher Candidates Towards Roma Pupils in Serbia and Slovenia--Case Studies  

Science.gov (United States)

In many countries, there is a growing need for teacher awareness and sensitivity to cultural differences, what is often called culturally responsive teaching. This is why teacher education institutions are making significant efforts to require student teachers to enrol in courses that focus on understanding, tolerance and acceptance of differences…

Pecek, Mojca; Macura-Milovanovic, Suncica; Vujisic-Živkovic, Nataša

2014-01-01

151

Culturally Responsive Pedagogy in Citizenship Education: Using African Proverbs as Tools for Teaching in Urban Schools  

Science.gov (United States)

Preparing today's children to be tomorrow's global citizens will require social educators who have knowledge of the histories, experiences, and cultural practices of the children they teach. This article offers culturally responsive pedagogy and the African proverb as frames for teaching African American students to become engaged local and global…

Grant, Rachel A.; Asimeng-Boahene, Lewis

2006-01-01

152

The response rate in postal epidemiological studies in the context of national cultural behaviour  

DEFF Research Database (Denmark)

The purpose of this study was to analyse the effect of national cultural differences on the response rate, obtained in questionnaire based epidemiological studies on allergy and asthma, performed in Sweden (DBH) and Bulgaria (ALLHOME). The two studies used one and the same methodology, but the obtained response rate was different: 78.8% in DBH and 34.5% in ALLHOME. The differences in the obtained response rate and the reasons for these differences were analyzed on the basis of the Hofstede’s cultural dimensions’ indexes, which clearly show the distinction in the national cultural behaviour of people in Sweden and Bulgaria. It was found that national culture could strongly influence the response behaviour of people in epidemiological studies and Hofstede’s indexes can be useful tool when designing and performing epidemiological studies, and in particular – questionnaire surveys.

Angelova, Radostina A.; Naydenov, Kiril

2012-01-01

153

30 Americans: An Inspiration for Culturally Responsive Teaching  

Science.gov (United States)

Art museums and other institutions of informal learning can promote multicultural understanding by collaborating with community ethnic groups and designing exhibitions that richly characterize the cultures they represent. Through the lens of educational programming for the exhibition "30 Americans," this article describes how both the Corcoran…

Powell, Linda S.

2012-01-01

154

Development of a Culturally Responsive Nutrition Promotion Course for Latinos  

Science.gov (United States)

The health of Hispanics is greatly influenced by level of education, socioeconomic status, and access to healthcare (United States Department of Health and Human Services [DHHS], 2011). To address this issue and to reduce health disparities among all ethnic groups, community based interventions with culturally appropriate and linguistically…

Frank, Gail C.; Beaudoin, Jessica; Rascon, Mayra; Garcia-Vega, Melawhy; Rios-Ellis, Britt

2013-01-01

155

Culturally Responsive Schools for Micronesian Immigrant Students. PREL Briefing Paper.  

Science.gov (United States)

This paper provides background information about the geography, language, culture, and political history of the Micronesian region, noting that Hawaii's public schools are experiencing an increase in the enrollment of children from Micronesia. Micronesia includes the Commonwealth of the Northern Mariana Islands; the three Freely Associated States…

Heine, Hilda C.

156

Responsibility-sensitive fair compensation in different cultures  

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Recently many philosophers and social choice theorists have questioned traditional welfare egalitarianism by introducing a notion of responsibility. They propose to distinguish between two sets of individual characteristics: those for which individuals are to be kept responsible and those for which they can be compensated. This approach raises the related questions of where to draw the line between those two sets of characteristics and how to operationalise the notion of 'responsibility-sensi...

Schokkaert, Erik; Devooght, Kurt

1999-01-01

157

Response of Cellulase Activity in pH-Controlled Cultures of the Filamentous Fungus Acremonium cellulolyticus  

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Cellulase production was investigated in pH-controlled cultures of Acremonium cellulolyticus. The response to culture pH was investigated for three cellulolytic enzymes, carbomethyl cellulase (CMCase), avicelase, and ?-glucosidase. Avicelase and ?-glucosidase showed similar profiles, with maximum activity in cultures at pH 5.5–6. The CMCase activity was highest in a pH 4 culture. At an acidic pH, the ratios of CMCase and avicelase activity to cellulase activity defined by filter paper uni...

Prasetyo, Joni; Sumita, Shyuuhei; Okuda, Naoyuki; Park, Enoch Y.

2009-01-01

158

Acute and chronic responses of denitrifying culture to diclofenac.  

Science.gov (United States)

Acute and chronic effect as well as biodegradation potential at different sludge retention times (SRTs) of a priority pollutant, diclofenac on denitrification process was assessed. The continuous amendment of the culture for 6months with 1?g/L diclofenac resulted in 30% decrease in gas production. The average diclofenac removal observed in the diclofenac-acclimated culture was less than 15%. Batch tests showed that nitrate was removed in diclofenac free-control reactor at a higher rate compared to diclofenac amended reactor. Although, SRT did not have any progressive effect on diclofenac degradation, the system operated at low SRT was more sensitive to diclofenac and resulted in an increase in N2O emission. Wastewater treatment plants (WWTPs) operated at higher SRTs may tolerate and recover from the adverse effects of such micropollutants. The study can lead to other researchers to understand the fate and effect of other emerging pollutants in the anoxic unit of WWTPs. PMID:25460991

Ozdemir, Gamze; Aydin, Egemen; Topuz, Emel; Yangin-Gomec, Cigdem; Okutman Tas, Didem

2015-01-01

159

Empowerment and responsibility of the culture of peace through education  

Directory of Open Access Journals (Sweden)

Full Text Available This article seeks to highlight the possibilities of empowering the culture of peace in the society in general, so it is necessary a joint work of different actors and social institutions. In this perspective each individual must transcend commitment to the peace of the personal to the social, also the State specifically in the case of Colombia must be monitored for compliance with the legislation in story to the compulsory education for educational institutions peace through public policies. Similarly, we emphasize that when they achieve consistently develop the principles and methodologies of education for peace, in institutions both family, school and University, this facilitates the strengthening of the culture for peace in the country.

Mariela Inés Sánchez Cardona

2012-01-01

160

Organisational Culture – Subcultures effect and response at an organizational change  

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Abstract Background : The company that this report addresses is, at time for investigation, in the midst of a change in organizational culture, where two departments with different core competencies are brought together into one. The purpose of this study is to review the potential problems that may occur in the change process when one or more subcultures come into conflict with organizational goals. Purpose and methodology: The reason for performing this study and the objectives are to exami...

Forslin, Karl

2012-01-01

 
 
 
 
161

The Impact of Learning Culture on Worker Response to New Technology  

Science.gov (United States)

Purpose: The aim of this paper is to provide a framework to measure the response of blue-collar workers to new technology in manufacturing and to establish the relationship between learning culture and that response. Design/methodology/approach: The data were collected with a survey questionnaire from 12 manufacturing sites that were implementing…

Reardon, Robert F.

2010-01-01

162

Histological Aspects of Anther Wall in Male Fertile and Cytoplasmic Male Sterile Helianthus annuus L. (Sunflower  

Directory of Open Access Journals (Sweden)

Full Text Available In this study, development of anther wall of Helianthus annuus L. male fertile HA 89 "B" line and cytoplasmic male sterile HA 89 "A" line were compared by light and electron microscopy. It was observed that there was no difference between male fertile HA 89 "B" line and male sterile HA 89 "A" line development of anther wall until tetrads were formed. After tetrad stage in male fertile HA 89 "B" line, middle layer was lost and tapetum was parted from anther wall and surrounded the microspores. In cytoplasmic male sterile HA 89 "A" line middle layer became vacuolated and widened, tapetum also enlarged and filled anther sac. Besides it was determined that middle layer and tapetum were permanent with epidermis and endothecial cell during the further development of anther wall and also there was no secondary thickening in endothecial cells. In conclusion we suggest that the plasmodial tapetum which developed in fertile HA 89 "B" line transferred nutrients to microspores and helped them develop normally, but in cytoplasmic male sterile HA 89 "A" line the plasmodial structure did not develop. The inner tangential wall of tapetum, which was adjacent to the tetrads did not degenerate, so that sufficient nutrients were not transferred to microspores and thus they degenerated while in their callose walls.

Ciler Meric

2004-01-01

163

The effects of corporate social responsibility on employees' affective commitment: a cross-cultural investigation.  

Science.gov (United States)

This study investigated the moderating effects of several Global Leadership and Organizational Behavior Effectiveness (GLOBE) cultural value dimensions on the relationship between employees' perceptions of their organization's social responsibility and their affective organizational commitment. Based on data from a sample of 1,084 employees from 17 countries, results showed that perceived corporate social responsibility (CSR) was positively related to employees' affective commitment (AC), after controlling for individual job satisfaction and gender as well as for nation-level differences in unemployment rates. In addition, several GLOBE value dimensions moderated the effects of CSR on AC. In particular, perceptions of CSR were more positively related to AC in cultures higher in humane orientation, institutional collectivism, ingroup collectivism, and future orientation and in cultures lower in power distance. Implications for future CSR research and cross-cultural human resources management are discussed. PMID:23067337

Mueller, Karsten; Hattrup, Kate; Spiess, Sven-Oliver; Lin-Hi, Nick

2012-11-01

164

Temperament trait of sensory processing sensitivity moderates cultural differences in neural response  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study focused on a possible temperament-by-culture interaction. Specifically, it explored whether a basic temperament/personality trait (sensory processing sensitivity; SPS), perhaps having a genetic component, might moderate a previously established cultural difference in neural responses when making context-dependent vs context-independent judgments of simple visual stimuli. SPS has been hypothesized to underlie what has been called inhibitedness or reactivity in infants, introversion ...

Aron, Arthur; Ketay, Sarah; Hedden, Trey; Aron, Elaine N.; Rose Markus, Hazel; Gabrieli, John D. E.

2010-01-01

165

Hormone-responsive 3D multicellular culture model of human breast tissue  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A hormone-responsive 3D human tissue-like culture system was developed in which human primary mammary epithelial cells (MECs) were co-cultured with two types of predominant mammary stromal cells on silk protein scaffolds. Silk porous scaffolds with incorporated extracellular matrix provided a compatible environment for epithelial structure morphogenesis and differentiation. The presence of stromal cells promoted MEC proliferation, induced both alveolar and ductal morphogenesis and enhanced ca...

Wang, Xiuli; Kaplan, David L.

2012-01-01

166

Effects of Cell Type and Culture Media on Interleukin-6 Secretion in Response to Environmental Particles  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Cultured lung cells provide an alternative to animal exposures for comparing the effects of different types of air pollution particles. Studies of particulate matter in vitro have reported proinflammatory cytokine signaling in response to many types of environmental particles, but there have been few studies comparing identical treatments in multiple cell types or identical cells with alternative cell culture protocols. We compared soil-derived, diesel, coal fly ash, titanium dioxide, and kao...

Veranth, John M.; Cutler, N. Shane; Kaser, Erin G.; Reilly, Christopher A.; Yost, Garold S.

2008-01-01

167

Listeria monocytogenes batch culture growth response to metabolic inhibitors.  

Science.gov (United States)

In certain environments nutrient and energy sources available to microorganisms can be limited. Foodborne pathogens must efficiently adapt in order to be successfully transmitted through the food chain to their hosts. For the intracellular foodborne pathogen Listeria monocytogenes, little is known regarding its response to nutrient/energy-limiting conditions. The alternative stress responsive sigma factor ?(B) has been reported to contribute to survival under specific stresses. Therefore, the effects of several metabolic inhibitors on growth of L. monocytogenes wild-type and a ?sigB mutant were examined. In the absence of inhibitors, both strains reached stationary phase after 18 h at 23°C and 10 h at 37°C. All of the metabolic inhibitors slowed growth of either strain, with few differences observed among the different inhibitors. PMID:25587784

Milillo, S R; Lungu, B; O'Bryan, C A; Dowd, S E; Muthaiyan, A; Johnson, M G; Ricke, S C

2015-02-01

168

Mapping of QTLs for androgenetic response based on a molecular genetic map of x Triticosecale Wittmack.  

Science.gov (United States)

Quantitative trait loci (QTLs) for androgenetic response were mapped in a doubled haploid (DH) population derived from the F1 hybrid of 2 unrelated varieties of triticale, 'Torote' and 'Presto'. A molecular marker linkage map of this cross was previously constructed using 73 DH lines. This map contains 356 markers (18 random amplified 5 polymorphic DNA, 40 random amplified microsatellite polymorphics, 276 amplified fragment length polymorphisms, and 22 simple sequence repeats) and was used for QTL analysis. The genome was well covered, and of the markers analysed, 336 were located in 21 linkage groups (81.9%) identified using SSR markers. The map covered a total length of 2465.4 cM with an average of 1 marker for each 6.9 cM. The distribution of the markers was not homogeneous across the 3 genomes, with 50.7% detected in the R genome. Several QTLs were found for the following variables related to the androgenetic response: number of embryos/100 anthers; plants regenerated from 100 embryos; number of green plants/total number of plants; and number of green plants/1000 anthers. Two were detected on chromosome 6B and 4R, which together had a 30% total influence on the induction of embryos. Another was found on 6B and on the unidentified LG1; these influenced the production of total plants from haploid embryo cultures. One QTL on chromosome 3R determined the photosynthetic viability of the haploid plantlets regenerated from microspores. Other QTLs were found on chromosomes 1B, 1R, 4R, and 7R, which helped the control of the final androgenetic response (the number of plantlets obtained for every 1000 anthers cultured). PMID:16391669

González, Juan M; Muñiz, Luis M; Jouve, Nicolás

2005-12-01

169

A low molecular weight proteome comparison of fertile and male sterile 8 anthers of Zea mays.  

Science.gov (United States)

During maize anther development, somatic locular cells differentiate to support meiosis in the pollen mother cells. Meiosis is an important event during anther growth and is essential for plant fertility as pollen contains the haploid sperm. A subset of maize male sterile mutants exhibit meiotic failure, including ms8 (male sterile 8) in which meiocytes arrest as dyads and the locular somatic cells exhibit multiple defects. Systematic proteomic profiles were analysed in biological triplicates plus technical triplicates comparing ms8 anthers with fertile sibling samples at both the premeiotic and meiotic stages; proteins from 3.5 to 20 kDa were fractionated by 1-D PAGE, cleaved with Lys-C and then sequenced using a LTQ Orbitrap Velos MS paradigm. Three hundred and 59 proteins were identified with two or more assigned peptides in which each of those peptides were counted at least two or more times (0.4% peptide false discovery rate (FDR) and 0.2% protein FDR); 2761 proteins were identified with one or more assigned peptides (0.4% peptide FDR and 7.6% protein FDR). Stage-specific protein expression provides candidate stage markers for early anther development, and proteins specifically expressed in fertile compared to sterile anthers provide important clues about the regulation of meiosis. 49% of the proteins detected by this study are new to an independent whole anther proteome, and many small proteins missed by automated maize genome annotation were validated; these outcomes indicate the value of focusing on low molecular weight proteins. The roles of distinctive expressed proteins and methods for mass spectrometry of low molecular weight proteins are discussed. PMID:22748129

Wang, Dongxue; Adams, Christopher M; Fernandes, John F; Egger, Rachel L; Walbot, Virginia

2012-10-01

170

Adaptive response of yeast cultures (Saccharomyces Cerevisiae) exposed to low dose of gamma radiation  

International Nuclear Information System (INIS)

The present study was planned as follows: (i) setting up of standard experimental conditions for investigation of radio-induced adaptive response in lower Eucaryotes; (ii) developing of procedures for synchronizing Saccharomyces cerevisiae X 310 D cell cultures and cell cycle stages monitoring; (iii) investigation of gamma (Co-60) and UV irradiation effects on the viability of synchronized and non-synchronized cell cultures of Saccharomyces cerevisiae; the effects were correlated with the cell density and cell cycle stage; (iv) study of the adaptive response induced by irradiation and setting up of the experimental conditions for which this response is optimized. The irradiations were performed by using a Co-60 with doses of 102 - 104 Gy and dose rates ranging from 2.2 x 102 Gy/h to 8.7 x 103 Gy/h. The study of radioinduced adaptive response was performed by applying a pre-irradiation treatment of 100-500 Gy, followed by challenge doses of 2-4 kGy delivered at different time intervals, ranging from 1 h to 4 h. The survival rate of synchronized and non-synchronized cultures as a function of exposure dose shows an exponential decay shape. No difference in viability of the cells occurred between synchronized and non-synchronized cultures. The pre-irradiation of cells with 100 and 200 Gy were most efficient to induce an adaptive response for the yeast cells. In this stage of work we proved the occurrence of the adaptive responseed the occurrence of the adaptive response in the case of synchronized yeast cultures exposed to gamma radiation. The results will be used in the future to investigate the dependence of this response on the cell cycle and the possibility to induce such a response by a low level electromagnetic field. (authors)

171

Cell biological analyses of anther morphogenesis and pollen viability in Arabidopsis and rice.  

Science.gov (United States)

Major advances have been made in recent years in our understanding of anther development through a combination of genetic studies, cell biological technologies, biochemical analysis, microarray and high-throughput sequencing-based approaches. In this chapter, we summarize the widely used protocols for pollen viability staining; the investigation of anther morphogenesis by light microscopy of semi-thin sections; TUNEL assay for programmed tapetum cell death; and laser microdissection procedures to obtain specialized cells or cell layers for carrying out transcriptomics. PMID:24395258

Chang, Fang; Zhang, Zaibao; Jin, Yue; Ma, Hong

2014-01-01

172

Callus culture and gamma rays treatment used for inducing new breeding material in wheat (Tr. Aestivum L.)  

International Nuclear Information System (INIS)

Naturally occuring somaclonal variation has been combined with gamma-ray (137Cs) treatment to increase the frequency of new forms of wheat differing from the initial lines. Two winter wheat genotypes 8-61 and 148-133-14 were used in the present study. Donor plants were grown under field conditions. Immature embryos were excised from the sterilized kernels and plated on MS basal medium supplemented with 2 mg/l 2.4-D for induction and proliferation of the callus. The following treatments were applied: 1). Control (a natural occuring somaclonal variation). 2). 60 Gy gamma-ray treatment on mature seeds. 3). 6.5 Gy gamma-ray treatment on immature seeds. 4). 2 Gy gamma-ray treatment on the callus 14 days after embryo plating. 5). 0.5 Gy gamma-ray treatment on the callus at the end of each plating. The best callusogenesis and regeneration were observed with genotype 8-61 given the treatment 5 followed by control. The genotype 148-133-14 showed a different response. The highest regeneration was obtained in the control followed by the treatments 2 and 5. In order to provide a faster stabilization of the genetic diversity among the regenerated plants, they were used as donors for anther culture. The anthers with microspores at the mid- to late uninucleate stages were excised and planted on potato-2 medium. Callus and embryoids induced from the cultured anthers were transferred to a 190-2 regeneration medium. All regenerants were studied cytologically and the haploidsere studied cytologically and the haploids were treated with 0.055 colhicine 2% dimethyl sulfoxide (DMSO). Doubled haploid lines were produced as a result of this experiment. Statistical analysis of the newly released lines showed evidence of differences in plant height, spike shape and other agronomic features. (author)

173

Probiotics in fish and shellfish culture: immunomodulatory and ecophysiological responses.  

Science.gov (United States)

Aquaculture is emerging as one of the most viable and promising enterprises for keeping pace with the surging need for animal protein, providing nutritional and food security to humans, particularly those residing in regions where livestock is relatively scarce. With every step toward intensification of aquaculture practices, there is an increase in the stress level in the animal as well as the environment. Hence, disease outbreak is being increasingly recognized as one of the most important constraints to aquaculture production in many countries, including India. Conventionally, the disease control in aquaculture has relied on the use of chemical compounds and antibiotics. The development of non-antibiotic and environmentally friendly agents is one of the key factors for health management in aquaculture. Consequently, with the emerging need for environmentally friendly aquaculture, the use of alternatives to antibiotic growth promoters in fish nutrition is now widely accepted. In recent years, probiotics have taken center stage and are being used as an unconventional approach that has numerous beneficial effects in fish and shellfish culture: improved activity of gastrointestinal microbiota and enhanced immune status, disease resistance, survival, feed utilization and growth performance. As natural products, probiotics have much potential to increase the efficiency and sustainability of aquaculture production. Therefore, comprehensive research to fully characterize the intestinal microbiota of prominent fish species, mechanisms of action of probiotics and their effects on the intestinal ecosystem, immunity, fish health and performance is reasonable. This review highlights the classifications and applications of probiotics in aquaculture. The review also summarizes the advancement and research highlights of the probiotic status and mode of action, which are of great significance from an ecofriendly, sustainable, intensive aquaculture point of view. PMID:24419543

C De, Bidhan; Meena, D K; Behera, B K; Das, Pronob; Das Mohapatra, P K; Sharma, A P

2014-06-01

174

Cultural Responsibility of Subjects in Moral Education in Colleges and Universities  

Directory of Open Access Journals (Sweden)

Full Text Available In a new era, to come to full understanding of the cultural responsibility of subjects in moral education in colleges and universities is an internal demand of modern educational theory for overall development of both teachers and students, and is the premise to play the leading role of teachers and mobilize the subjectivity of university students. At the same time, this also guides the direction for teachers and students to carry out moral education activities in colleges and universities. This article explains the responsibility of subjects in moral education in colleges and universities from the perspective of culture.

Chunyan Chen

2011-07-01

175

Materializing Culture - Culturizing Material. On the Status, Responsibilities and Function of Cultural Property Repositories within the Framework of a "Transformative Scholarship"  

Directory of Open Access Journals (Sweden)

Full Text Available Certain theoretical streams in the cultural and social sciences that are occasionally subsumed under the term “New Materialism” 2 (see Witzgall, as well as recent social, political, cultural and media technology developments require a theoretical and research-political repositioning of academic object repositories. For it is obvious that under the influence of these multi-layered, partly interwoven processes, the status, responsibilities, as well as the function and spheres of activity of these object or cultural property repositories with research commitment (on the term see section 2 below are currently undergoing long-lasting change. For the respective institutions, these changes not only result in complex challenges regarding contents and structure, but also present extraordinary opportunities for the fulfillment of their academic, social and political responsibilities. The appropriate handling of these challenges and opportunities can substantially contribute to the sharpening of the academic and social profile of these institutions and increase their visibility on both a national and international level.

Markus Hilgert

2014-12-01

176

A primary culture of guinea pig gallbladder epithelial cells that is responsive to secretagogues  

Science.gov (United States)

We have developed a cell culture of guinea pig gallbladder epithelial cells with which to study ion transport. When grown on permeable supports, the cultured epithelia developed a transepithelial resistance (Rt) of ?500 ?·cm2. The epithelial cell origin of the cell culture was further confirmed by immunocytochemical localization of cytokeratin. Ionomycin and forskolin increased transepithelial voltage and short-circuit current (Isc) and decreased Rt. The response to ionomycin was transient, whereas that to forskolin was sustained. Both were attenuated by replacement of Cl? and/or HCO3?. Mucosal addition of the anion transport inhibitors DIDS or diphenylamine-2-carboxylic acid (DPC) blocked the response to ionomycin. The response to forskolin was blocked by DPC but not by DIDS. Ionomycin, but not forskolin, increased intracellular Ca2+ concentration in fura 2-loaded cells. PGE2, histamine, vasoactive intestinal polypeptide, and secretin elicited a sustained increase in Isc. Responses to ATP and CCK were transient. Thus cultured guinea pig gallbladder epithelia display the range of responses observed in the native tissue and are an appropriate model for studies of ion transport in gallbladder and intestinal epithelia. PMID:11052982

Gunter-Smith, Pamela J.; Abdulkadir, Oluwakemi; Hammonds-Odie, Latanya; Scanlon, Mary; Terrell, Raquel

2015-01-01

177

Isolation and culture of soybean (Glycine max L. Merrill) microspores and pollen grains  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Nas últimas três décadas, a pesquisa em embriogênese do micrósporo de soja restringiu-se ao cultivo in vitro de anteras, com inúmeras limitações, como o pequeno número de micrósporos responsivos e o alto potencial embriogênico dos tecidos esporofíticos. Por isso, foi executada uma seqüência de teste [...] s visando ao estabelecimento de condições adequadas para o isolamento e o cultivo in vitro de micrósporos e grãos de pólen, como um sistema alternativo ao cultivo de anteras. Inicialmente, uma técnica de isolamento foi desenvolvida usando botões florais de quatro cultivares de soja (Bragg, IAS 5, MG/BR-46 Conquista e BRSMT Uirapuru), a qual possibilitou o estabelecimento de cultivos com características e densidade satisfatórias. Posteriormente, diferentes condições de cultivo foram testadas. Apesar de os meios B5 e MS serem recomendados para o cultivo de anteras de soja, o melhor resultado foi obtido em meio PTA-15 modificado, como o aumento do tamanho dos micrósporos e a formação de 0,4% de grãos de pólen multicelulares na cultivar BRSMT Uirapuru. Abstract in english In the last three decades, research on soybean microspore embryogenesis was restricted to anther culture, which presents limitations such as the small number of responsive microspores and the high embryogenic potential of sporophytic tissues. Therefore, a sequence of studies was performed to establi [...] sh appropriate conditions for the isolation and culture of soybean microspores and pollen grains as an alternative to anther culture. First, a pollen and microspore isolation technique was developed using floral buds from four soybean cultivars (Bragg, IAS 5, MG/BR-46 Conquista and BRSMT Uirapuru). This technique allowed the establishment of cultures with satisfactory density and characteristics. Subsequently, different culture conditions were tested. Although B5 and MS media have been currently recommended for soybean anther culture, the best result was obtained in PTA-15 modified medium, with the formation of enlarged microspores and 0.4% of multicellular pollen grains in the cultivar BRSMT Uirapuru.

Lia Rosane, Rodrigues; Bianca de Camargo, Forte; Maria Helena, Bodanese-Zanettini.

2006-07-01

178

Response of cellulase activity in pH-controlled cultures of the filamentous fungus Acremonium cellulolyticus.  

Science.gov (United States)

Cellulase production was investigated in pH-controlled cultures of Acremonium cellulolyticus. The response to culture pH was investigated for three cellulolytic enzymes, carbomethyl cellulase (CMCase), avicelase, and beta-glucosidase. Avicelase and beta-glucosidase showed similar profiles, with maximum activity in cultures at pH 5.5-6. The CMCase activity was highest in a pH 4 culture. At an acidic pH, the ratios of CMCase and avicelase activity to cellulase activity defined by filter paper unit were high, but at a neutral pH, the beta-glucosidase ratio was high. The pH 6.0 culture showed the highest cellulase activity within the range of pH 3.5-6.5 cultures. The saccharification activity from A. cellulolyticus was compared to those of the cellulolytic enzymes from other species. The A. cellulolyticus culture broth had a saccharification yield comparable to those of the Trichoderma enzymes GC220 and Cellulosin T2, under conditions with the same cellulase activity. The saccharification yields from Solka floc, Avicel, and waste paper, measured as the percent of released reducing sugar to dried substrate, were greater than 80% after 96 h of reaction. The yields were 16% from carboxymethylcellulose and 26% from wood chip refiner. Thus, the A. cellulolyticus enzymes were suitable for converting cellulolytic biomass to reducing sugars for biomass ethanol production. This study is a step toward the establishment of an efficient system to reutilize cellulolytic biomass. PMID:19882113

Prasetyo, Joni; Sumita, Shyuuhei; Okuda, Naoyuki; Park, Enoch Y

2010-09-01

179

Making String Education Culturally Responsive: The Musical Lives of African American Children  

Science.gov (United States)

The purpose of this study was to explore the violin experiences of African American students at an Elementary School in northern Florida to consider the potential for culturally-responsive string education. The hermeneutical approach was used to answer the research questions: (1) What are the personal musical worlds of these African American…

Boon, Ebru Tuncer

2014-01-01

180

Retelling as a Culturally Responsive Strategy for Micronesian Students: Eduard's Story.  

Science.gov (United States)

A qualitative study examined the use of retelling as a culturally responsive strategy for Micronesian students. More specifically, it examined the effect of the retelling strategy on the literacy development of an 11-year-old Micronesian student from Chuuk over the course of 9 months in a fifth-grade Guam classroom. Results showed increases in the…

Stoicovy, Catherine E.

 
 
 
 
181

Australian Readers' Responses to the Cross-Cultural, Folklore-Based Fantasy Novels of Patricia Wrightson.  

Science.gov (United States)

In the 1970s and 1980s the white Australian author Patricia Wrightson's cross-cultural fantasies concerning the conflict of White characters with Aboriginal folk spirits struck a chord with many adolescent and adult readers who judged these novels to be outstandingly successful. A classroom-based study examined the responses of a class of seventh…

Tobin, Barbara

182

Writing the Male Abuser in Cultural Responses to Domestic Violence in Spain  

Science.gov (United States)

The article analyzes the portrayal of the male perpetrator of heterosexual domestic violence in a selection of contemporary Spanish texts (novel, drama, and autobiography) that form part of a clearly discernible cultural response to the issue of intimate partner violence in Spain today. It reads the figure of the abuser in conjunction with a range…

Godsland, Shelley

2012-01-01

183

Reading Instruction for Diverse Classrooms: Research-Based, Culturally Responsive Practice  

Science.gov (United States)

This practical, teacher-friendly book provides indispensable guidance for implementing research-based reading instruction that is responsive to students' diverse cultural and linguistic backgrounds. Structured around the "big five" core topics of an effective reading program--phonemic awareness, phonics, fluency, vocabulary, and comprehension--the…

McIntyre, Ellen; Hulan, Nancy; Layne, Vicky

2010-01-01

184

Moving from Contemplation to Preparation: Is Counseling Psychology Ready to Embrace Culturally Responsive Prevention?  

Science.gov (United States)

The confluence of prevention, multicultural competence and cultural responsiveness, and social justice is embryonic but holds much promise. The author uses the stages of change model to heighten awareness of how counseling psychologists are situated to provide well-developed system-level interventions and to examine the organizational and…

Adams, Eve M.

2007-01-01

185

The Impact of an International Student Teaching Program on the Cultural Responsiveness of Participants  

Science.gov (United States)

The purpose of this research was to explore the ways in which immersion into an international student teaching experience through participation in an international student teaching program can enhance the cultural responsiveness of American pre-service teachers. The population included in this study was eight students, including alumni, who…

Allaman, Lisa St. Louis

2012-01-01

186

Teaching about Race in an Urban History Class: The Effects of Culturally Responsive Teaching  

Science.gov (United States)

The authors examined the effects of a culturally responsive teacher's pedagogy on urban low-income African American and Latino high school students' interpretations of racial diversity, racism, and individual and collective agency in U. S. history. The authors found that students incorporated instruction about the diversity and agency of people of…

Epstein, Terrie; Mayorga, Edwin; Nelson, Joseph

2011-01-01

187

Developing Sociopolitical Consciousness at Freedom Schools: Implications for Culturally Responsive Teacher Preparation  

Science.gov (United States)

This article describes the programmatic ways in which the Children's Defense Fund Freedom Schools[R] program develops culturally responsive teaching practices amongst its summer interns, particularly in the area of developing sociopolitical consciousness. This paper places specific focus on the role that historical knowledge, the acknowledgement…

Jackson, Tambra O.

2011-01-01

188

A Cross-Cultural Examination of Preschool Teacher Cognitions and Responses to Child Aggression  

Science.gov (United States)

The associations among preschool teachers' attributions about child responsibility, intentionality, knowledge, and the seriousness of hypothetical displays of children's aggressive behavior are examined in United States ("N"?=?82) and Vietnamese ("N"?=?91) preschool teachers. The results suggest cross-cultural

Pochtar, Randi; Del Vecchio, Tamara

2014-01-01

189

Culturally responsive middle school science: A case study of needs, demands, and challenges  

Science.gov (United States)

Culturally responsive programming has been proposed as a remedy for the well-documented disconnect between schools and the ethnically and culturally diverse students who attend them. These programs often focus on creating instructional materials and pedagogical practices that are aligned with the knowledges, perspectives and practices of these students. This study builds on that literature and examines the needs, demands, and challenges of developing a culturally responsive health science program for ethnically and culturally diverse urban middle school students. I approached this problem through a content analysis of the intended curriculum and a microethnography of the enacted curriculum. In my analysis of the intended curriculum, I adapted a science textbook analysis instrument created by the American Association for the Advancement of Science (AAAS) to include criteria related to identified features of culturally responsive education. Using these modified analytic criteria, I found that the pilot drafts of the curricular materials excelled in the areas of engaging students in relevant phenomenon but lacked many of these specifically culturally responsive elements. Recommendations were made to redress these deficiencies. In my analysis of the enacted curriculum, I observed in five eighth grade classrooms where the program was being implemented. I used participant observation, audio and video tape recordings, artifacts, and interviews over a six-month period to investigate teacher/student interactions, the social organization of the classrooms, and students' culturally distinctive knowledge resources---or what is sometimes referred to as their "funds of knowledge." I found that the affective interactions between teachers and students were precursors to any reform, and that students and teachers similarly defined these interactions as "teacher care." In addition, I found that the social organization of the classroom often privileged official content and ways of knowing while limiting students' ability to publicly draw on their unique funds of knowledge or to access their scientific sensemaking resources. Through the use of data accumulated from my curriculum analysis and classroom observations, I concluded that culturally responsive program development must incorporate both curricular development and inservice professional development focused not only on science but also on fundamental aspects of classroom interactions.

Woodrow, Kelli Ellen

2007-12-01

190

Chemical residues and biochemical responses in wild and cultured European sea bass (Dicentrarchus labrax L.)  

International Nuclear Information System (INIS)

Cultured and wild sea bass (Dicentrarchus labrax) from the Arade Estuary were sampled in summer and winter and the degree of exposure to metals and polycyclic aromatic hydrocarbons (PAHs) assessed, together with some biochemical responses against those and other pollutants. The highest levels of copper (up to 997 ?g g-1 dry weight) and cadmium (up to 4.22 ?g g-1 dry weight) were detected in the liver and kidney of cultured specimens, whereas the highest exposure to PAHs was observed in wild fish. Significant alterations in some biochemical markers were detected and associated to pollutant exposure. Thus, metallothionein concentrations were higher in the tissues of cultured fish and positively correlated with metal residues. The activity 7-ethoxyresorufin O-deethylase ranged from 28 pmol/min/mg protein in cultured fish to 83 pmol/min/mg protein in wild fish collected near a marina area. Cultured fish and wild fish from the marina area had depressed acetylcholinesterase in muscle tissue and a parasitic infection in the gonads. The obtained results support the usefulness of the combined use of chemical and biochemical markers to assess the impact of anthropogenic pollutants in both wild and cultured fish

191

Rat Sertoli cells acquire a. beta. -adrenergic response during primary culture  

Energy Technology Data Exchange (ETDEWEB)

Two-dimensional polyacrylamide gel electrophoresis and the radioligand (-)-(/sup 125/I)iodopindolol (/sup 125/I-Pin) have been used to study isoproterenol-dependent protein phosphorylation and ..beta..-adrenergic receptor availability, respectively, in cultured Sertoli cells and freshly isolated seminiferous tubular segments of sexually immature and mature rats. Sertoli cells prepared from sexually immature rats show progressive /sup 125/I-Pin binding in primary cultures that correlates with isoproterenol-induced cell shape changes, redistribution of immunoreactive vimentin, and phosphorylation of this intermediate filament protein. Seminiferous tubules do not show significant isoproterenol-dependent vimentin phosphorylation nor /sup 125/I-Pin binding. However, vimentin phosphorylation can be induced by follicle-stimulating hormone or a cyclic nucleotide analog. This study stresses the need for correlating pharmacological-induced responses observed in Sertoli cell primary cultures with those in the intact seminiferous tubule.

Kierszenbaum, A.L.; Spruill, W.A.; White, M.G.; Tres, L.L.; Perkins, J.P.

1985-04-01

192

Culture modulates the brain response to human expressions of emotion: Electrophysiological evidence.  

Science.gov (United States)

To understand how culture modulates on-line neural responses to social information, this study compared how individuals from two distinct cultural groups, English-speaking North Americans and Chinese, process emotional meanings of multi-sensory stimuli as indexed by both behaviour (accuracy) and event-related potential (N400) measures. In an emotional Stroop-like task, participants were presented face-voice pairs expressing congruent or incongruent emotions in conditions where they judged the emotion of one modality while ignoring the other (face or voice focus task). Results indicated that while both groups were sensitive to emotional differences between channels (with lower accuracy and higher N400 amplitudes for incongruent face-voice pairs), there were marked group differences in how intruding facial or vocal cues affected accuracy and N400 amplitudes, with English participants showing greater interference from irrelevant faces than Chinese. Our data illuminate distinct biases in how adults from East Asian versus Western cultures process socio-emotional cues, supplying new evidence that cultural learning modulates not only behaviour, but the neurocognitive response to different features of multi-channel emotion expressions. PMID:25477081

Liu, Pan; Rigoulot, Simon; Pell, Marc D

2015-01-01

193

In vitro culture in barley breeding  

International Nuclear Information System (INIS)

One of the most useful biotechnics for plant breeders is in vitro culture of anthers or miscropores to induce haploids and homozygous diploids. High frequency of microspore-derived diploid plants could be produced by culturing anthers on Ficoll medium. The segregation ratios of certain morphological characters were not random and could be shifted by culture conditions. It was reported by a number of authors that true breeding and highly productive genotypes were obtained from microspore-derived diploid plants and doubled haploids derived from bulbosom techniques. There is a great possibility that a selective system for desirable characters can be built in an in vitro culture system. Where haploids can be induced in crop plants, they provide the most rapid technique for producing homozygous lines. Since the genetically controlled factors in homozygous lines are fixed and will be identical in the future generations, it becomes possible for a plant breeder to evaluate quantitative characters such as yield and quality very early in the breeding program. There are two methods which have been used extensively for production of homozygous diploid barley plants. They are bulbosum techniques and anther culture methods. (author). 14 refs, 5 tabs

194

Temperament trait of sensory processing sensitivity moderates cultural differences in neural response.  

Science.gov (United States)

This study focused on a possible temperament-by-culture interaction. Specifically, it explored whether a basic temperament/personality trait (sensory processing sensitivity; SPS), perhaps having a genetic component, might moderate a previously established cultural difference in neural responses when making context-dependent vs context-independent judgments of simple visual stimuli. SPS has been hypothesized to underlie what has been called inhibitedness or reactivity in infants, introversion in adults, and reactivity or responsivness in diverse animal species. Some biologists view the trait as one of two innate strategies-observing carefully before acting vs being first to act. Thus the central characteristic of SPS is hypothesized to be a deep processing of information. Here, 10 European-Americans and 10 East Asians underwent functional magnetic resonance imaging while performing simple visuospatial tasks emphasizing judgments that were either context independent (typically easier for Americans) or context dependent (typically easier for Asians). As reported elsewhere, each group exhibited greater activation for the culturally non-preferred task in frontal and parietal regions associated with greater effort in attention and working memory. However, further analyses, reported here for the first time, provided preliminary support for moderation by SPS. Consistent with the careful-processing theory, high-SPS individuals showed little cultural difference; low-SPS, strong culture differences. PMID:20388694

Aron, Arthur; Ketay, Sarah; Hedden, Trey; Aron, Elaine N; Rose Markus, Hazel; Gabrieli, John D E

2010-06-01

195

Corporate Social Responsibility and Culture : A Study of European Multinational Corporations’ adaptation of Community Involvement Practices  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Corporate social responsibility (CSR), which has emerged as a global trend, has gained increased focus in the everyday media and among practitioners on the political agenda. CSR has also risen as an important research topic in the field of organization. This study investigates European multinational corporations’ tendencies to adapt CSR policies and practices, or more specifically corporate community involvement, to different national cultures. The paper explores if/how and why companies wi...

Henriksson, Sebastian; Hodjikj, Armin; Ognyanova Dinkova, Evgeniya

2012-01-01

196

An Empirical Research on Chinese-English Bilinguals’ Compliment Responses—A Cross-cultural Perspective  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Compliments and compliment responses (CRs) are decided by linguistic and sociocultural norms, and further reflect cultural values and social norms. The study of CRs has generated a great number of studies in pragmatics. Previous studies, including Chinese as participants, have investigated Chinese CRs and compared Chinese CRs with people of other languages. According to Holmes’ (1988) taxonomy, CRs can be classified into three categories: Agreeing, Deflecting/Evading and Rejecting. L...

Xuehua An

2013-01-01

197

Microbotryum silenes-saxifragae sp. nov. sporulating in the anthers of Silene saxifraga in southern European mountains.  

Science.gov (United States)

Currently, the monophyletic lineage of anther smuts on Caryophyllaceae includes 22 species classified in the genus Microbotryum. They are model organisms studied in many disciplines of fungal biology. A molecular phylogenetic approach was used to resolve species boundaries within the caryophyllaceous anther smuts, as species delimitation based solely on phenotypic characters was problematic. Several cryptic species were found amongst the anther smuts on Caryophyllaceae, although some morphologically distinct species were discernible, and most species were characterized by high host-specificity. In this study, anther smut specimens infecting Silene saxifraga were analysed using rDNA sequences (ITS and LSU) and morphology to resolve their specific status and to discuss their phylogenetic position within the lineage of caryophyllaceous anther smuts. The molecular phylogeny revealed that all specimens form a monophyletic lineage that is supported by the morphological trait of reticulate spores with tuberculate interspaces (observed in certain spores). This lineage cannot be attributed to any of the previously described species, and the anther smut on Silene saxifraga is described and illustrated here as a new species, Microbotryum silenes-saxifragae. This species clusters in a clade that includes Microbotryum species, which infect both closely and distantly related host plants growing in diverse ecological habitats. It appears possible that host shifts combined with changes to ecological host niches drove the evolution of Microbotryum species within this clade. PMID:23898410

Pi?tek, Marcin; Lutz, Matthias; Kemler, Martin

2013-07-01

198

The Arabidopsis LFR gene is required for the formation of anther cell layers and normal expression of key regulatory genes.  

Science.gov (United States)

The anther is the male reproductive organ in flowering plants. Although some genes were reported to be involved in anther development, the molecular mechanisms underlying the transcriptional regulation of these genes is unclear. lfr-2 (leaf and flower related-2), the null allele of Arabidopsis thaliana LFR (LEAF AND FLOWER RELATED), was male-sterile. The anthers of lfr-2 plants were defective in sporogenous cell formation, tapetum development, and pollen development. In agreement with these phenotypes, expression studies showed that LFR was expressed in all cell layers of the anther, and that expression was particularly strong in the tapetal cells and pollen grains. Quantitative RT-PCR analysis revealed that LFR is required for the normal transcription of some anther development-related genes, such as AMS, CALS5, and DYT1, MS1 and MS2, and ROXY2. Genetic analysis showed that SPL was epistatic to LFR while LFR was epistatic to DYT1. We propose that LFR may be a crucial component in the regulation of a genetic network that modulates anther development. PMID:22461668

Wang, Xiu-Tang; Yuan, Can; Yuan, Ting-Ting; Cui, Su-Juan

2012-09-01

199

Contrasting Nephropathic Responses to Oral Administration of Extract of Cultured Penicillium polonicum in Rat and Primate  

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Full Text Available Liquid- or solid substrate-cultured Penicillium polonicum administered in feed to rats over several days evokes a histopathological response in kidney involving apoptosis and abnormal mitosis in proximal tubules. The amphoteric toxin is yet only partly characterized, but can be isolated from cultured sporulating biomass in a fraction that is soluble in water and ethanol, and exchangeable on either anion- or cation-exchange resins. After several weeks of treatment renal proximal tubule distortion became striking on account of karyocytomegaly, but even treatment for nearly two years remained asymptomatic. Extract from a batch of solid substrate fermentation of P. polonicum on shredded wheat was incorporated into feed for rats during four consecutive days, and also given as an aqueous solution by oral gavage to a vervet monkey daily for 10 days. Treatment was asymptomatic for both types of animal. Rat response was evident as the typical renal apoptosis and karyomegaly. In contrast there was no such response in the primate; and neither creatinine clearance nor any haematological characteristic or serum component concentration deviated from a control or from historical data for this primate. The contrast is discussed concerning other negative findings for P. polonicum in pigs and hamsters. Renal karyomegaly, as a common rat response to persistent exposure to ochratoxin A, is not known in humans suspected as being exposed to more than the usual trace amounts of dietary ochratoxin A. Therefore the present findings question assumptions that human response to ochratoxin A conforms to that in the rat.

John E. Fincham

2010-08-01

200

Map-Based Cloning of Genes Important for Maize Anther Development  

Science.gov (United States)

Map-Based cloning for maize mutant MS13 . Scientists still do not understand what decides the fate of a cell in plants. Many maize genes are important for anther development and when they are disrupted, the anthers do not shed pollen, i.e. male sterile. Since the maize genome has been fully sequenced, we conduct map-based cloning using a bulk segregant analysis strategy. Using PCR (polymerase chain reaction), we look for biomarkers that are linked to our gene of interest, Male Sterile 13 (MS13). Recombinations occur more often if the biomarkers are further away from the gene, therefore we can estimate where the gene is and design more PCR primers to get closer to our gene. Genetic and molecular analysis will help distinguish the role of key genes in setting cell fates before meiosis and for being in charge of the switch from mitosis to meiosis.

Anaya, Y.; Walbot, V.; Nan, G.

2012-12-01

 
 
 
 
201

Effect of 60Co ?-rays irradiation pretreatment on callus inductivity and differentiation of strawberry anther  

International Nuclear Information System (INIS)

Strawberry buds, in which a majority of pollen had single nuclear keeping to the side, were pretreated by 60Co ?-rays irradiation at different doses. The irradiation effect on the callus inductivity and plant differentiation rate of strawberry anther were studied. The results indicated that the pretreatment by 60Co ?-rays could increase the anther callus inductivity and plant differentiation rate significantly, and 20 Gy was the best dose. The callus inductivity of Akihime and Toyonoka increased by 39.09% and 35.68%, respectively, compared with the no-pretreatment materials. On the same media, the plant differentiation rate of Akihime and Toyonoka were also increased by 6.67%-6.72% and 4.73%-6.45%, respectively, compared with the two varieties of no-pretreatment. (authors)

202

Phenol red in tissue culture media is a weak estrogen: implications concerning the study of estrogen-responsive cells in culture.  

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Although much attention has been paid to the removal of hormones from sera and to the development of serum-free media for studies on hormone-responsive cells in culture, little consideration has been given to the possibility that the media components themselves may have hormonal activity. We have found that phenol red, which bears a structural resemblance to some nonsteroidal estrogens and which is used ubiquitously as a pH indicator in tissue culture media, has significant estrogenic activit...

Berthois, Y.; Katzenellenbogen, J. A.; Katzenellenbogen, B. S.

1986-01-01

203

Pollen development and fertilization in Arabidopsis is dependent on the MALE GAMETOGENESIS IMPAIRED ANTHERS gene encoding a Type V P-type ATPase  

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In flowering plants, development of the haploid male gametophytes (pollen grains) takes place in a specialized structure called the anther. Successful pollen development, and thus reproduction, requires high secretory activity in both anther tissues and pollen. In this paper, we describe a novel member of the eukaryotic type V subfamily (P5) of P-type ATPase cation pumps, the MALE GAMETOGENESIS IMPAIRED ANTHERS (MIA) gene. MIA protein is highly abundant in the endoplasmic reticulum and small ...

Jakobsen, Mia Kyed; Poulsen, Lisbeth R.; Schulz, Alexander; Fleurat-lessard, Pierrette; Møller, Annette; Husted, Søren; Schiøtt, Morten; Amtmann, Anna; Palmgren, Michael G.

2005-01-01

204

Nutritional lipid supply can control the heat shock response of B16 melanoma cells in culture.  

Science.gov (United States)

The in vitro culture of cells offers an extremely valuable method for probing biochemical questions and many commonly-used protocols are available. For mammalian cells a source of lipid is usually provided in the serum component. In this study we examined the question as to whether the nature of the lipid could become limiting at high cell densities and, therefore, prospectively influence the metabolism and physiology of the cells themselves. When B16 mouse melanoma cells were cultured, we noted a marked decrease in the proportions of n-3 and n-6 polyunsaturated fatty acids (PUFAs) with increasing cell density. This was despite considerable quantities of these PUFAs still remaining in the culture medium and seemed to reflect the preferential uptake of unesterified PUFA rather than other lipid classes from the media. The reduction in B16 total PUFA was reflected in changes in about 70% of the molecular species of membrane phosphoglycerides which were analysed by mass spectrometry. The importance of this finding lies in the need for n-3 and n-6 PUFA in mammalian cells (which cannot synthesize their own). Although the cholesterol content of cells was unchanged the amount of cholesterol enrichment in membrane rafts (as assessed by fluorescence) was severely decreased, simultaneous with a reduced heat shock response following exposure to 42°C. These data emphasize the pivotal role of nutrient supply (in this case for PUFAs) in modifying responses to stress and highlight the need for the careful control of culture conditions when assessing cellular responses in vitro. PMID:22583025

Péter, Mária; Balogh, Gábor; Gombos, Imre; Liebisch, Gerhard; Horváth, Ibolya; Török, Zsolt; Nagy, Enik?; Maslyanko, Andriy; Benk?, Sándor; Schmitz, Gerd; Harwood, John L; Vígh, László

2012-11-01

205

Developmental regulation of the gene for chimeric calcium/calmodulin-dependent protein kinase in anthers  

Science.gov (United States)

Chimeric Ca(2+)/calmodulin-dependent protein kinase (CCaMK) was cloned from developing anthers of lily (Lilium longiflorum Thumb. cv. Nellie White) and tobacco (Nicotiana tabacum L. cv. Xanthi). Previous biochemical characterization and structure/function studies had revealed that CCaMK has dual modes of regulation by Ca(2+) and Ca(2+)/calmodulin. The unique structural features of CCaMK include a catalytic domain, a calmodulin-binding domain, and a neural visinin-like Ca(2+)-binding domain. The existence of these three features in a single polypeptide distinguishes it from other kinases. Western analysis revealed that CCaMK is expressed in a stage-specific manner in developing anthers. Expression of CCaMK was first detected in pollen mother cells and continued to increase, reaching a peak around the tetrad stage of meiosis. Following microsporogenesis, CCaMK expression rapidly decreased and at later stages of microspore development, no expression was detected. A tobacco genomic clone of CCaMK was isolated and transgenic tobacco plants were produced carrying the CCaMK promoter fused to the beta-glucuronidase reporter gene. Both CCaMK mRNA and protein were detected in the pollen sac and their localizations were restricted to the pollen mother cells and tapetal cells. Consistent results showing a stage-specific expression pattern were obtained by beta-glucuronidase analysis, in-situ hybridization and immunolocalization. The stage- and tissue-specific appearance of CCaMK in anthers suggests that it could play a role in sensing transient changes in free Ca(2+) concentration in target cells, thereby controlling developmental events in the anther.

Poovaiah, B. W.; Xia, M.; Liu, Z.; Wang, W.; Yang, T.; Sathyanarayanan, P. V.; Franceschi, V. R.

1999-01-01

206

Extensive Divergence Between Mating-Type Chromosomes of the Anther-Smut Fungus  

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Genomic regions that determine mating compatibility are subject to distinct evolutionary forces that can lead to a cessation of meiotic recombination and the accumulation of structural changes between members of the homologous chromosome pair. The relatively recent discovery of dimorphic mating-type chromosomes in fungi can aid the understanding of sex chromosome evolution that is common to dioecious plants and animals. For the anther-smut fungus, Microbotryum lychnidis-dioicae (= M. violaceu...

Hood, Michael E.; Petit, Elsa; Giraud, Tatiana

2013-01-01

207

Distribution of the anther-smut pathogen Microbotryum on species of the Caryophyllaceae  

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Understanding disease distributions is of fundamental and applied importance, yet few studies benefit from integrating broad sampling with ecological and phylogenetic data. Here, anther-smut disease, caused by the fungus Microbotryum, was assessed using herbarium specimens of Silene and allied genera of the Caryophyllaceae.A total of 42 000 herbarium specimens were examined, and plant geographical distributions and morphological and life history characteristics were tested as correlates of di...

Hood, Michael E.; Mena-ali?, Jorge I.; Gibson, Amanda K.; Oxelman, Bengt; Giraud, Tatiana; Yockteng, Roxana; Arroyo, Mary T. K.; Conti, Fabio; Pedersen, Amy B.; Gladieux, Pierre; Antonovics, Janis

2010-01-01

208

An Arabidopsis flavonoid transporter is required for anther dehiscence and pollen development  

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FLOWER FLAVONOID TRANSPORTER (FFT) encodes a multidrug and toxin efflux family transporter in Arabidopsis thaliana. FFT (AtDTX35) is highly transcribed in floral tissues, the transcript being localized to epidermal guard cells, including those of the anthers, stigma, siliques and nectaries. Mutant analysis demonstrates that the absence of FFT transcript affects flavonoid levels in the plant and that the altered flavonoid metabolism has wide-ranging consequences. Root growth, seed development ...

Thompson, Elinor P.; Wilkins, Christopher; Demidchik, Vadim; Davies, Julia M.; Glover, Beverley J.

2010-01-01

209

The examination of Hevea brasiliensis plants produced by in vitro culture and mutagenesis by DNA fingerprinting techniques  

International Nuclear Information System (INIS)

Rubber (Hevea brasiliensis) plants derived from anther and ovule culture as well as gamma-irradiated plants were examined by several DNA marker techniques. These include restriction fragment length polymorphisms (RFLPs), random amplified polymorphic DNA (RAPD), sequence tagged microsatellite sites (STMS), DNA amplification fingerprinting (DAF) and amplified fragment length polymorphisms (AFLPs). Compared to control plants produced by vegetative propagation (cutting and budding), plants produced by in vitro culture appeared to have a reduction in the number of rDNA loci. Two RAPD protocols were compared and found to be similar in amplification of the major DNA bands. After confirmation that the RAPD method adopted was reproducible, the technique was applied to the present studies. Eight out of the 60 primers screened were able to elicit polymorphisms between pooled DNA from in vitro culture plants. Variations in DNA patterns were observed between pooled DNA samples of anther-derived plants as well as between anther-derived and ovule-derived plants. Comparisons of RAPD patterns obtained between anther-derived plants exposed to increasing dosages of gamma-irradiation with non irradiated anther-derived plants revealed distinct DNA polymorphisms. The changes in DNA profiles did not appear to be correlated to the dosage of irradiation. Since somaclonal variation was detected, it was difficult to identify changes which were specifically caused by irradiation. Application of the STMS technique to tag micro satellite sequences (GA)n, (TA)n and (TTA)n in the hydroxymethylglutaryl coenzyme A reductase-1 (hmgr-1) gene failed to detect differences between plants derived from anther and ovule culture. Although restriction endonuclease digestions with methylation sensitive enzymes suggested that four in vitro culture plants examined exhibited similar digestion patterns as the controls, a change in cytosine methylation in one anther-derived plant was detected. Examination of individual in vitro culture plants by the DAF technique revealed genetic heterogeneity among these plants. Differences in DNA profiles between anther-derived and ovule-derived plants were also detected. In general, more somaclonal variations were detected in anther-derived than ovule-derived plants. When the DAF technique was applied to DNA obtained from leaves of irradiated budded stumps, DNA profiles were shown to be different from non irradiated controls. Whilst DNA patterns of samples irradiated at the same dosage displayed similar DNA patterns, these varied with increasing dosage. Examination of in vitro culture plants by AFLPs confirmed earlier results that somaclonal variations were present in Hevea. (author)

210

Identification of an Arabidopsis plasma membrane-located ATP transporter important for anther development.  

Science.gov (United States)

ATP acts as an extracellular signal molecule in plants. However, the nature of the mechanisms that export this compound into the apoplast are under debate. We identified the protein PM-ANT1 as a candidate transporter able to mediate ATP export. PM-ANT1 joins the mitochondrial carrier family, lacks an N-terminal amino acid extension required for organelle localization, and locates to the plasma membrane. Recombinant PM-ANT1 transports ATP, and the gene is substantially expressed in mature pollen grains. Artificial microRNA (amiRNA) mutants show reduced silique length and less seeds per silique but increased seed weight associated with unchanged pollen viability. Anthers from amiRNA mutants exhibited a normal early development, but stomium breakage is inhibited, leading to impaired anther dehiscence. This results in reduced self-pollination and thus decreased fertilization efficiency. amiRNA pollen grains showed increased intracellular ATP levels but decreased extracellular ATP levels. The latter effects are in line with transport properties of recombinant PM-ANT1, supporting in planta that functional PM-ANT1 resides in the plasma membrane and concur with the PM-ANT1 expression pattern. We assume that PM-ANT1 contributes to ATP export during pollen maturation. ATP export may serve as an extracellular signal required for anther dehiscence and is a novel factor critical for pollination and autogamy. PMID:21540435

Rieder, Benjamin; Neuhaus, H Ekkehard

2011-05-01

211

Differential proteomic analysis of anthers between cytoplasmic male sterile and maintainer lines in Capsicum annuum L.  

Science.gov (United States)

Cytoplasmic male sterility (CMS), widely used in the production of hybrid seeds, is a maternally inherited trait resulting in a failure to produce functional pollen. In order to identify some specific proteins associated with CMS in pepper, two-dimensional gel electrophoresis (2-DE) was applied to proteomic analysis of anthers/buds between a CMS line (designated NA3) and its maintainer (designated NB3) in Capsicum annuum L. Thirty-three spots showed more than 1.5-fold in either CMS or its maintainer. Based on mass spectrometry, 27 spots representing 23 distinct proteins in these 33 spots were identified. Proteins down-regulated in CMS anthers/buds includes ATP synthase D chain, formate dehydrogenase, alpha-mannosidas, RuBisCO large subunit-binding protein subunit beta, chloroplast manganese stabilizing protein-II, glutathione S-transferase, adenosine kinase isoform 1T-like protein, putative DNA repair protein RAD23-4, putative caffeoyl-CoA 3-O-methyltransferase, glutamine synthetase (GS), annexin Cap32, glutelin, allene oxide cyclase, etc. In CMS anthers/buds, polyphenol oxidase, ATP synthase subunit beta, and actin are up-regulated. It was predicted that male sterility in NA3 might be related to energy metabolism turbulence, excessive ethylene synthesis, and suffocation of starch synthesis. The present study lays a foundation for future investigations of gene functions associated with pollen development and cytoplasmic male sterility, and explores the molecular mechanism of CMS in pepper. PMID:24264042

Wu, Zhiming; Cheng, Jiaowen; Qin, Cheng; Hu, Zhiqun; Yin, Caixia; Hu, Kailin

2013-01-01

212

Flavonoids in white and yellow perianths and yellow anthers of tulips (Tulipa gesneriana L.  

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Full Text Available The content of flavonoids in white and yellow perianths and yellow anthers of a few tulip cultivars were determined at the stage of full flowering. To analyses of flavonols a HPLC method was used. In anthers (yellow of all analyzed cultivars (Oscar, Pax, Profesor Wóycicki, Bia?a Dama, White Virgin, Calypso, Diana high content of quercetin (2,35 - 6,01 mg·g-1 F.W., kaempferol (1,09 - 9,47 mg·g-1 F.W. and apigenin (1,34 - 8,24 mg·g-1 F.W. was found. In analyzed white perianth of cvs. Oscar and White Virgin also high content of quercetin (1,3 - 1,80 mg·g-1 F.W. and kaempferol (1,90 mg·g-1 F.W. was documented and only traces of apigenin was found. In the yellow perianth of cv. Profesor Wóycicki the level of quercetin and kaempferol was much lower than in perianth of cvs. Oscar and White Virgin, and apigenin was absent. Thus, yellow anthers and white and yellow perianth of tulip cultivars are a rich source of flavonols.

Marcin Horbowicz

2001-12-01

213

Immunolocalization of Lipoxygenase in the Anther Wall Cells of Lathyrus undulatus Boiss. during Programmed Cell Death  

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Full Text Available Lipoxygenase catalyzes oxygenation of long chain fatty acids to hydroperoxides and is involved in the degradation of membranes occuring in some types of programmed cell death (PCD. The localization of lipoxygenase in the anther wall layers of L. undulatus during cellular degradation was analyzed by immunogold labeling technique at young and vacuolated pollen stage, due to the close relation between lipoxygenase activity and membrane degradation in programmed cell death. Immunoreaction to lipoxygenase was monitored slightly at young pollen stage in the anther wall cells. As programmed cell death signals progress, lipoxygenase revealed in anther wall cells intensely. At vacuolated pollen stage tapetal cells came forward with ultrastructural changes such as cell, organelle and membrane disintegration. At the indicated stage immunogold particles indicating sites of LOX PAb-binding epitopes were located in the nucleus (chromatin was condensed and lined at the periphery, cytoplasm and close to long dilated rough endoplasmic reticulum (RER cisterna. In conclusion lipoxygenase increase which has a role in the membrane degeneration, possibly induced the collapse of tonoplast, nuclear and plasma membrane and triggered programmed cell death in the tapetal cells of L. undulatus as well as the other wall cells.

Meral ÜNAL

2011-05-01

214

Differential Proteomic Analysis of Anthers between Cytoplasmic Male Sterile and Maintainer Lines in Capsicum annuum L.  

Directory of Open Access Journals (Sweden)

Full Text Available Cytoplasmic male sterility (CMS, widely used in the production of hybrid seeds, is a maternally inherited trait resulting in a failure to produce functional pollen. In order to identify some specific proteins associated with CMS in pepper, two-dimensional gel electrophoresis (2-DE was applied to proteomic analysis of anthers/buds between a CMS line (designated NA3 and its maintainer (designated NB3 in Capsicum annuum L. Thirty-three spots showed more than 1.5-fold in either CMS or its maintainer. Based on mass spectrometry, 27 spots representing 23 distinct proteins in these 33 spots were identified. Proteins down-regulated in CMS anthers/buds includes ATP synthase D chain, formate dehydrogenase, alpha-mannosidas, RuBisCO large subunit-binding protein subunit beta, chloroplast manganese stabilizing protein-II, glutathione S-transferase, adenosine kinase isoform 1T-like protein, putative DNA repair protein RAD23-4, putative caffeoyl-CoA 3-O-methyltransferase, glutamine synthetase (GS, annexin Cap32, glutelin, allene oxide cyclase, etc. In CMS anthers/buds, polyphenol oxidase, ATP synthase subunit beta, and actin are up-regulated. It was predicted that male sterility in NA3 might be related to energy metabolism turbulence, excessive ethylene synthesis, and suffocation of starch synthesis. The present study lays a foundation for future investigations of gene functions associated with pollen development and cytoplasmic male sterility, and explores the molecular mechanism of CMS in pepper.

Zhiming Wu

2013-11-01

215

Tomato Male sterile 1035 is essential for pollen development and meiosis in anthers.  

Science.gov (United States)

Male fertility in flowering plants depends on proper cellular differentiation in anthers. Meiosis and tapetum development are particularly important processes in pollen production. In this study, we showed that the tomato male sterile (ms10 (35) ) mutant of cultivated tomato (Solanum lycopersicum) exhibited dysfunctional meiosis and an abnormal tapetum during anther development, resulting in no pollen production. We demonstrated that Ms10 (35) encodes a basic helix-loop-helix transcription factor that is specifically expressed in meiocyte and tapetal tissue from pre-meiotic to tetrad stages. Transgenic expression of the Ms10 (35) gene from its native promoter complemented the male sterility of the ms10 (35) mutant. In addition, RNA-sequencing-based transcriptome analysis revealed that Ms10 (35) regulates 246 genes involved in anther development processes such as meiosis, tapetum development, cell-wall degradation, pollen wall formation, transport, and lipid metabolism. Our results indicate that Ms10 (35) plays key roles in regulating both meiosis and programmed cell death of the tapetum during microsporogenesis. PMID:25262227

Jeong, Hee-Jin; Kang, Jin-Ho; Zhao, Meiai; Kwon, Jin-Kyung; Choi, Hak-Soon; Bae, Jung Hwan; Lee, Hyun-Ah; Joung, Young-Hee; Choi, Doil; Kang, Byoung-Cheorl

2014-12-01

216

An Empirical Research on Chinese-English Bilinguals’ Compliment Responses—A Cross-cultural Perspective  

Directory of Open Access Journals (Sweden)

Full Text Available Compliments and compliment responses (CRs are decided by linguistic and sociocultural norms, and further reflect cultural values and social norms. The study of CRs has generated a great number of studies in pragmatics. Previous studies, including Chinese as participants, have investigated Chinese CRs and compared Chinese CRs with people of other languages. According to Holmes’ (1988 taxonomy, CRs can be classified into three categories: Agreeing, Deflecting/Evading and Rejecting. Looking from a cross-cultural perspective, Chinese tend to use less Accepting strategies and more Rejecting strategies than Australians do (Tang and Zhang, 2009. Within the same language community, CR strategies might also change over time, as has been suggested in Chen and Yang’s (2010. However, research on Chinese English-knowing bilinguals’ CRs in the two languages is rare. The present study, focuses on a group of Chinese English-knowing bilinguals’ CR speech act. It aims at finding out whether Chinese English bilinguals will respond to compliments differently, when they are exposed to different media—Chinese language and English language, which might shed new light on how language influences and shapes people’s social and cultural norms. Written discourse completion task (DCT is used to elicit the participants’ responses to compliments on one’s look, ability, character, possession. The survey was conducted on a cohort of 31 Chinese English teachers, during the period when they were in Singapore. Results show that there are differences in CR strategies employed in Chinese DCT and English DCT.

Xuehua An

2013-09-01

217

Response of cultured human airway epithelial cells to X-rays and energetic ?-particles  

International Nuclear Information System (INIS)

Radon and its progeny, which emit ?-particles during decay, may play an important role in inducing human lung cancer. To gain a better understanding of the biological effects of ?-particles in human lung we studied the response of cultured human airway epithelial cells to X-rays and monoenergetic helium ions. Experimental results indicated that the radiation response of primary cultures was similar to that for airway epithelial cells that were transformed with a plasmid containing an origin-defective SV40 virus. The RBE for cell inactivation determined by the ratio of D0 for X-rays to that for 8 MeV helium ions was 1.8-2.2. The cross-section for helium ions, calculated from the D0 value, was about 24 ?m2 for cells of the primary culture. This cross-section is significantly smaller than the average geometric nuclear area (? 180 ?m2), suggesting that an average of 7.5 ?-particles (8 MeV helium ions) per cell nucleus are needed to induce a lethal lesion. (author)

218

Regulation and manipulation of flavonoid gene expression in anthers of petunia: the molecular basis of the Po mutation.  

Science.gov (United States)

Molecular mechanisms governing development of the male reproductive organs of flowers, the anthers, are largely unknown. In this article, we report on the investigation of the molecular basis of a mutation involving the expression of a gene encoding the flavonoid biosynthesis enzyme chalcone flavanone isomerase (CHI) in anthers of petunia. In petunia, the gene Po regulates the expression of CHI in anthers: PoPo petunia lines contain CHI enzyme activity in petals and anthers, whereas popo lines contain the CHI enzyme only in petals but not in anthers. As a result of the Po mutation, the substrate of CHI accumulates and therefore the pollen of a popo line are yellow or greenish. The genome of petunia contains two chi genes, chiA and chiB. In a restriction fragment length polymorphism analysis, a 100% linkage was observed between Po and chiA. This result suggested that Po is identical to chiA and that Po is not a regulatory gene of chiA. Introduction of a chiA gene isolated from a PoPo line into a popo line resulted in a complementation of the mutation that was directly visible because the pollen color shifted from yellow to white. This proved that chiA and Po are identical. Because chiA encodes a functional CHI enzyme in flower petals of a popo line, we propose that the Po mutation is a mutation in the regulatory region of chiA abolishing chiA promoter activity in anthers but not in corollas. This change in anther color is a fine illustration of how floral pigmentation can be manipulated in a predictable way and suggests the use of CHI as a visible marker. PMID:1824333

van Tunen, A J; Mur, L A; Recourt, K; Gerats, A G; Mol, J N

1991-01-01

219

Porcine sapovirus replication is restricted by the type I interferon response in cell culture.  

Science.gov (United States)

Porcine sapovirus (PSaV) of the family Caliciviridae, is the only member of the genus Sapovirus with cell culture and reverse genetics systems. When combined with the piglet model, these approaches provide a system to understand the molecular basis of sapovirus pathogenesis. The replication of PSaV in cell culture is, however, restricted, displaying an absolute requirement for bile acids and producing lower levels of infectious virus than other caliciviruses. The effect of bile acids has previously been linked to a reduction in the signal transducer and activator of transcription (STAT1)-mediated signalling pathway. In the current study, we observed that even in the presence of bile acids, PSaV replication in cell culture was restricted by soluble factors produced from infected cells. This effect was at least partially due to secreted IFN because treatment of cells with recombinant porcine IFN-? resulted in significantly reduced viral replication. Moreover, IFN-mediated signalling pathways (IFN, STAT1 and the 2',5'-oligoadenylate synthetase) were activated during PSaV infection. Characterization of PSaV growth in cell lines deficient in their ability to induce or respond to IFN showed a 100-150-fold increase in infectious virus production, indicating that the primary role of bile acids was not the inactivation of the innate immune response. Furthermore, the use of IFN-deficient cell lines enabled more efficient recovery of PSaV from cDNA constructs. Overall, the highly efficient cell culture and reverse genetics system established here for PSaV highlighted the key role of the innate immune response in the restriction of PSaV infection and should greatly facilitate further molecular studies on sapovirus host-cell interactions. PMID:25304652

Hosmillo, Myra; Sorgeloos, Frédéric; Hiraide, Rintaro; Lu, Jia; Goodfellow, Ian; Cho, Kyoung-Oh

2015-01-01

220

Porcine sapovirus replication is restricted by the type I interferon response in cell culture  

Science.gov (United States)

Porcine sapovirus (PSaV) of the family Caliciviridae, is the only member of the genus Sapovirus with cell culture and reverse genetics systems. When combined with the piglet model, these approaches provide a system to understand the molecular basis of sapovirus pathogenesis. The replication of PSaV in cell culture is, however, restricted, displaying an absolute requirement for bile acids and producing lower levels of infectious virus than other caliciviruses. The effect of bile acids has previously been linked to a reduction in the signal transducer and activator of transcription (STAT1)-mediated signalling pathway. In the current study, we observed that even in the presence of bile acids, PSaV replication in cell culture was restricted by soluble factors produced from infected cells. This effect was at least partially due to secreted IFN because treatment of cells with recombinant porcine IFN-? resulted in significantly reduced viral replication. Moreover, IFN-mediated signalling pathways (IFN, STAT1 and the 2?,5?-oligoadenylate synthetase) were activated during PSaV infection. Characterization of PSaV growth in cell lines deficient in their ability to induce or respond to IFN showed a 100–150-fold increase in infectious virus production, indicating that the primary role of bile acids was not the inactivation of the innate immune response. Furthermore, the use of IFN-deficient cell lines enabled more efficient recovery of PSaV from cDNA constructs. Overall, the highly efficient cell culture and reverse genetics system established here for PSaV highlighted the key role of the innate immune response in the restriction of PSaV infection and should greatly facilitate further molecular studies on sapovirus host–cell interactions. PMID:25304652

Hosmillo, Myra; Sorgeloos, Frédéric; Hiraide, Rintaro; Lu, Jia

2015-01-01

 
 
 
 
221

Antimicrobial peptide response to Group B Streptococcus in human extraplacental membranes in culture  

Science.gov (United States)

Objective Streptococcus agalactiae (GBS) is an important cause of chorioamnionitis. This study characterizes GBS colonization and stimulation of antimicrobial responses in human extraplacental membranes using an ex vivo transwell two-compartment system of full-thickness membranes and live GBS. Study Design Human extraplacental membranes were affixed to transwell frames (without synthetic membranes). Live GBS was added to the decidual side of membranes in transwell cultures, and cocultures were incubated for 4, 8 and 24 h. GBS recovery from homogenized membranes and culture medium was determined by enumerating colony forming units (CFU) on blood agar. Antimicrobial peptide expression was identified using immunohistochemistry and ELISA. GBS killing by HBDs was assessed in vitro by incubating GBS with different human beta defensins (HBDs) for 3 h, then enumerating CFU. Results GBS recovery from membranes markedly decreased over time (P < 0.05). The antimicrobial peptides HBD-1, HBD-2, HBD-3, and lactoferrin were expressed in both GBS-exposed and non-exposed tissues. Notably, a pattern of localized increased HBD-2 in the amnion of GBS-infected tissue was observed. Moreover, GBS-treated membranes released increased amounts of HBD-2 into the amniotic and decidual compartments of the transwell cultures after 24 h (P < 0.05). In bacterial cultures, HBD-2 decreased GBS viability in a concentration-dependent manner (P < 0.05). Conclusion Innate immune responses in ex vivo human extraplacental membranes suppress GBS growth. HBD-2 was implicated in this GBS suppression with evidence of signal transduction across the tissue. Antimicrobial peptides may be important for innate immune defense against intrauterine GBS infections during pregnancy. PMID:23562109

Boldenow, Erica; Jones, Sarah; Lieberman, Richard W.; Chames, Mark C.; Aronoff, David M.; Xi, Chuanwu; Loch-Caruso, Rita

2013-01-01

222

Intra and interspecific variability of in vitro culture response in Lycopersicon (tomatoes)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese A variabilidade intra e interespecífica foi avaliada no gênero Lycopersicon para as variáveis: taxa de produtividade (PR, número total de brotos/número total de culturas), percentagem de regeneração (%R, número de culturas que regeneraram brotos ou primórdios/número total de culturas) e percentagem [...] de calo (%C, número de culturas que só desenvolveram calo/número total de culturas). Os explantes foliares de vários genótipos de L. esculentum, L. esculentum var. ceraciforme, L. pimpinellifolium e L. peruvianum foram colocados em meio de cultura Murashige and Skoog (Physiol. Plant. 15: 473-493, 1962) + 0.175 mg/l AIA + 2.25 mg/l BA. Detectaram-se diferenças significativas entre espécies e entre genótipos de uma mesma espécie, apresentando genótipos de diferentes espécies a mesma resposta. Abstract in english Intra and interspecific variability was measured in the genus Lycopersicon for the traits: productivity rate (PR, total number of regenerated shoots/total number of cultures), regeneration percentage (%R, number of cultures regenerating shoots or primordia/total number of cultures) and callus percen [...] tage (%C, number of cultures only producing callus/total number of cultures). Leaf explants from various genotypes of L. esculentum, L. esculentum var. cerasiforme, L. pimpinellifolium and L. peruvianum were placed on Murashige and Skoog (Physiol. Plant. 15: 473-493, 1962) medium + 0.175 mg/l IAA + 2.25 mg/l BA. Significant differences among species and among genotypes within the same species were found, while genotypes from different species showed similar responses.

Guillermo, Pratta; Roxana, Zorzoli; Liliana Amelia, Picardi.

1997-03-01

223

A noninvasive transfer system for polarized renal tubule epithelial cell sheets using temperature-responsive culture dishes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We used temperature-responsive culture dishes onto which the temperature-responsive polymer, poly(Nisopropylacrylamide), was covalently grafted for tissue engineering. Confluent cells harvested as intact sheets from these surfaces by simple temperature reduction can be transferred to various surfaces including additional culture dishes, other cell sheets, and tissues. In order to examine the maintenance of cell polarity, Madin-Darby canine kidney cells and human primary renal proximal tubule ...

Kushida A.; Yamato M.; Isoi Y.; Kikuchi A.; Okano T.

2005-01-01

224

Cadmium inhibition of vitamin D-mediated responses in organ-cultured embryonic chick duodenum  

Energy Technology Data Exchange (ETDEWEB)

When added to the medium, cadmium inhibits 1..cap alpha..,25-dihydroxycholecalciferol-mediated responses in the organ-cultured embryonic chick duodenum: decreases induction of a specific calcium-binding protein (CaBP), prevents the elevation of alkaline phosphatase activity, and reduces the ability of the tissue to absorb radiocalcium at the mucosal surface. The cadmium effect is clearly not generalized cytotoxicity. These results may be taken as evidence that cadmium can interfere with vitamin D action at the level of the target organ itself and is not necessarily secondary to alteration in vitamin D metabolism.

Corradino, R.A.

1979-01-01

225

A Sensitive Sensor Cell Line for the Detection of Oxidative Stress Responses in Cultured Human Keratinocytes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the progress of allergic and irritant contact dermatitis, chemicals that cause the generation of reactive oxygen species trigger a heat shock response in keratinocytes. In this study, an optical sensor cell line based on cultured human keratinocytes (HaCaT cells) expressing green fluorescent protein (GFP) under the control of the stress-inducible HSP70B’ promoter were constructed. Exposure of HaCaT sensor cells to 25 µM cadmium, a model substance for oxidative stress induction, provoked...

Ute Hofmann; Melanie Priem; Christine Bartzsch; Thomas Winckler; Karl-Heinz Feller

2014-01-01

226

Leiomyoma cells in 3-dimensional cultures demonstrate an attenuated response to fasudil, a rho-kinase inhibitor, when compared to 2-dimensional cultures.  

Science.gov (United States)

Uterine leiomyomata are common benign tumors in women of reproductive age and demonstrate an attenuated response to mechanical signaling that involves Rho and integrins. To further characterize the impairment in Rho signaling, we studied the effect of Rho-kinase inhibitor, fasudil, on extracellular matrix production, in 2-dimensional (2D) and 3-dimensional (3D) cultures of leiomyoma and myometrial cells. Leiomyoma 2D cultures demonstrated a rapid decrease in gene transcripts and protein for fibronectin, procollagen 1A, and versican. In 3D cultures, fibronectin and procollagen 1A proteins demonstrated increased levels at lower concentrations of fasudil, followed by a concentration-dependent decrease. Versican protein increased up to 3-fold, whereas fibromodulin demonstrated a significant decrease of 1.92-fold. Myometrial 2D or 3D cultures demonstrated a decrease in all proteins after 72 hours of treatment. The 3D leiomyoma cultures demonstrated a significant increase in active RhoA, followed by a concentration-dependent decrease at higher concentrations. A concentration-dependent increase in phospho-extracellular regulated signal kinase and proapoptotic protein Bax was observed in 3D leiomyoma cultures. Fasudil relaxed the contraction of the 3D collagen gels caused by myometrium and leiomyoma cell growth. These findings indicate that the altered state of Rho signaling in leiomyoma was more clearly observed in 3D cultures. The results also suggest that fasudil may have clinical applicability for treatment of uterine leiomyoma. PMID:25084783

Malik, Minnie; Britten, Joy; Segars, James; Catherino, William H

2014-09-01

227

Chromosomal responses to ionizing radiation reminiscent of an adaptive response in cultured Chinese hamster cells  

International Nuclear Information System (INIS)

When Chinese hamster V79 cells were internally exposed to low level chronic ?-rays from incorporated tritiated thymidine, they showed an 'adaptive' response to the induction of chromosomal damage by subsequent higher acute doses of ?-rays. The yield of sister-chromatid exchanges in the 3H-dThd pretreated cells was less than the yield induced by ?-rays alone, and the micronucleus frequency was less than the sum of the induced frequencies by 3H-dThd and ?-rays separately. No adaptation to the micronucleus induction by ?-rays was observed after the 3H-adapted cells had divided once and when 3-aminobenzamide was given before the challenge doses. The cross-resistance study revealed that the 3H-adapted cells were resistant to SCE induction but not to the micronucleus inductions by the challenge doses of reactor radiations. The results suggest that the SCE adaptation and the micronucleus adaptation or clastogenic adaptation are probably caused by different, inducible adaptive repair pathways. 46 refs.; 5 figs.; 1 table

228

A Letter of Apology Nearly 50 Years in the Making: How We've Failed to Solve the Cultural Bind of the American Male. Response to "The Cultural Bind of the American Male"  

Science.gov (United States)

This article presents the author's letter of apology as a response to "The Cultural Bind of the American Male". In the letter, the author offers his apologies because educators have failed to solve the cultural bind of the American male.

McCandless, Greg

2012-01-01

229

Isoflavone Augmentation in Soybean Cell Cultures Is Optimized Using Response Surface Methodology.  

Science.gov (United States)

Glycine max contains potential therapeutic isoflavones, and its productivity in plants is considerably influenced worldwide by several biotic and abiotic factors. Optimization of soybean cell suspension cultures (Indian variety, JS 335) to maximize the cell growth and isoflavone production in the present study was performed using response surface methodology (RSM) with three independent variables of plant growth regulators, 2,4-dichlorophenoxyacetic acid (2,4-D), 1-naphthalene acetic acid (?-NAA), and kinetin (Kn). The maximum biomass achieved was 70.62 g/L dry weight (dw) using the optimized medium of 2.10 mg/L 2,4-D, 5.52 mg/L ?-NAA, and 0.35 mg/L Kn supplemented in the Murashige and Skoog (MS) basal medium. The total isoflavone content of 38.59 mg/g of dw was obtained in the medium with optimized conditions of 1.33 mg/L 2,4-D, 1.76 mg/L ?-NAA, and 0.15 mg/L Kn. In comparison to field-grown soybean seeds, the cell suspension cultures profoundly augmented isoflavone concentrations. The optimized conditions for both biomass and total isoflavone content were evaluated by superimposing the contour plots. The results suggested that the optimized medium of cell suspension cultures possibly be used for scale-up studies in bioreactors to offer a high content of bioactive isoflavones. PMID:24678665

Akitha Devi, M K; Giridhar, P

2014-03-31

230

Transcription of storage protein genes in cultured Brassica napus embryos in response to exogenous abscisic acid  

International Nuclear Information System (INIS)

Two major seed storage proteins, cruciferin and napin, accumulate during embryogeny in Brassica napus. We are determining whether the levels of storage protein mRNAs in cultured embryos are controlled at the transcriptional level in response to ABA. The nuclei were isolated from the embryos and incubated in a transcription mix with 32P-GTP, and the incorporation into specific RNAs was determined by DNA excess filter hybridization. The transcription rate of cruciferin increased about 2-fold, and the transcription rate of napin increased about 3- to 4-fold in ABA-treated embryos compared to embryos cultured on basal medium. This increase in transcription rate is consistent with the increases in RNA levels which are seen in parallel experiments. In the same experiments, the transcription rates of actin and the rRNA genes were unaffected by ABA. In reinduction experiments, embryos which were switched from basal medium to medium containing ABA at 12 or 24 h showed an increase in transcription rate of the seed storage protein genes to the same level as those which were cultured on ABA at time 0

231

Cytological characterization and allelism testing of anther developmental mutants identified in a screen of maize male sterile lines.  

Science.gov (United States)

Proper regulation of anther differentiation is crucial for producing functional pollen, and defects in or absence of any anther cell type result in male sterility. To deepen understanding of processes required to establish premeiotic cell fate and differentiation of somatic support cell layers a cytological screen of maize male-sterile mutants has been conducted which yielded 42 new mutants including 22 mutants with premeiotic cytological defects (increasing this class fivefold), 7 mutants with postmeiotic defects, and 13 mutants with irregular meiosis. Allelism tests with known and new mutants confirmed new alleles of four premeiotic developmental mutants, including two novel alleles of msca1 and single new alleles of ms32, ms8, and ocl4, and two alleles of the postmeiotic ms45. An allelic pair of newly described mutants was found. Premeiotic mutants are now classified into four categories: anther identity defects, abnormal anther structure, locular wall defects and premature degradation of cell layers, and/or microsporocyte collapse. The range of mutant phenotypic classes is discussed in comparison with developmental genetic investigation of anther development in rice and Arabidopsis to highlight similarities and differences between grasses and eudicots and within the grasses. PMID:23390600

Timofejeva, Ljudmilla; Skibbe, David S; Lee, Sidae; Golubovskaya, Inna; Wang, Rachel; Harper, Lisa; Walbot, Virginia; Cande, William Zacheus

2013-02-01

232

Characterization of a novel anther-specific gene encoding a leucine-rich repeat protein in petunia.  

Science.gov (United States)

In Petunia x hybrida 'Fantasy Red', a leucine-rich repeat (LRR) gene referred to as PhLRR, was identified in a flower bud cDNA library. The open reading frame sequence of PhLRR was 1251 bp, encoding a putative 46.2-kDa protein of 416 amino acids. The PhLRR protein showed high similarity to members of polygalacturonase inhibitor proteins (PGIPs), contained 11 conserved LRR domains, and was an extracellular localization protein. Phylogenetic analysis showed that PhLRR belonged to the same PGIPs subfamily as SHY, indicating that PhLRR may be involved in the development of pollen-like SHY. Expression analysis revealed that PhLRR was abundantly expressed during early stages of flower bud and anther development, while it was not detected in any other examined organs, such as sepals, petals, pistils, roots, stems, leaves, or open flowers. Furthermore, many cis-acting elements (such as AGAAA and GTGA) related to anther-specific gene expression were identified in the PhLRR gene promoter region, indicating that the promoter is also anther-specific. These results suggested that PhLRR is a novel anther-specific gene that may be essential for the early development of anthers. PMID:25501199

Yue, Y Z; Sun, J; Huang, X; Peng, H; Liu, G F; Hu, H R

2014-01-01

233

Microbotryum heliospermae, a new anther smut fungus parasitic on Heliosperma pusillum in the mountains of the European Alpine System.  

Science.gov (United States)

The members of the smut genus Microbotryum are pathogens of a wide range of host plant species from nine dicotyledonous families. Within the genus, the species sporulating in anthers of Caryophyllaceae form a monophyletic group that in recent years attracted much interest in various biological studies. The phylogenetic framework developed for species delimitation within Microbotryum revealed that high level host-specificity is a major feature of most caryophyllaceous anther smuts. However, the great number of anther smut specimens on diverse host plant species reported worldwide has still not been included in phylogenetic analyses due to the inaccessibility of recently collected specimens, and thus many species remain still undiscovered. In this study, anther smut specimens on Heliosperma pusillum originating from all main mountain ranges of the European Alpine System were examined using partial rDNA sequence and/or morphological analyses. The investigation revealed that all specimens are morphologically uniform and phylogenetically represent a monophyletic lineage, sister to Microbotryum lagerheimii complex on Atocion rupestre/Silene lacera/Silene vulgaris/Viscaria vulgaris. This lineage cannot be attributed to any of the previously described species, and therefore the smut in anthers of H. pusillum is described and illustrated here as a new species, Microbotryum heliospermae. The species is known from subalpine zone of the Alps, the Carpathians, the Dinaric Alps, and the Pyrenees, inhabiting host plants growing in open spring communities or semihumid mountain meadows. PMID:22289764

Pi?tek, Marcin; Lutz, Matthias; Ronikier, Anna; Kemler, Martin; ?widerska-Burek, Urszula

2012-02-01

234

Effect of dexamethasone on the cytotoxic and enzymatic response of cultured endothelial cells to radiation  

International Nuclear Information System (INIS)

Experiments were conducted to determine (1) whether glucocorticoids directly protected endothelial cells (EC) from radiation and (2) if angiotensin converting enzyme (ACE) activity, known to be increased by glucocorticoid, played a role in the EC response to radiation. Confluent monolayers of EC cultured from bovine aorta EC were treated with dexamethasone (10-6 M); after irradiation (5.0 Gy, 60Co ?) ACE and lactate dehydrogenase (LDH) activities, DNA and protein contents, and nuclei number were measured. Combined dexamethasone treatment and radiation increased cellular ACE activity at a time when neither agent alone had an effect (24-hr dexamethasone exposure before 5 Gy and assayed 24 hr after 5 Gy). This interaction between radiation and dexamethasone treatment suggests that the glucocorticoid modifies the cell's response to injury. Although this interaction does not ameliorate radiation cytotoxicity, maintenance of ACE levels in injured vessels by hormones may have physiological significance in the hemodynamics of irradiated tissues

235

Indução de calos e regeneração de embriões em anteras de Coffea arabica L. por nitrato de prata e etileno / Callus induction and embryo regeneration in Coffea arabica L. anthers by silver nitrate and ethylene  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O melhoramento genético do cafeeiro por métodos convencionais é um processo demorado para aquisição de uma nova cultivar. Através da cultura de anteras podem-se obter linhagens homozigóticas rapidamente, oriundas de dihaplóides. O objetivo foi utilizar na cultura de anteras na cv. Catuaí Vermelho 99 [...] de Coffea arabica L., nitrato de prata (AgNO3) e etileno para induzir a formação de calos e regenerar plântulas dihaplóides. As anteras foram inoculadas em meio MS acrescido de 2 mg L-1 de 2,4-D com e sem AgNO3 (5 mg L-1), juntamente com etileno por diferentes dias: (testemunha; 2; 4; 6, e 8). Ao final de 12 dias, estas foram transferidas para o meio de regeneração, acrescido de 0,108 mg L-1 de cinetina. Foi observada uma oxidação e intumescimento maior nos primeiros dias de inoculação em exposição ao etileno, e a cv. Catuaí Vermelho 99 respondeu a formação de calos e também a embriogênese direta na presença do etileno. Abstract in english The genetic breeding of coffee by conventional methods to obtain new cultivars is time-consuming. Anther culture can yield homozygous lines quickly from bi-haploids. This study used anther cultures of Coffea arabica L. cv. Catuaí Vermelho 99, and tested the effect of silver nitrate (AgNO3) and ethyl [...] ene in callus-formation induction and bi-haploid seedling regeneration. The anthers were inoculated in MS to which 2 mg L-1 2,4-D had been added with AgNO3 (5 mg L-1) together with ethylene being introduced or not, for different periods (the control, 2, 4, 6, and 8 days). At the end of 12 days, the anthers were transferred to the regeneration medium, to which 0.108 mg L-1 kinetin had been added. Greater oxidation and intumescence were observed in the first days after exposure to ethylene; the cultivar Catuaí Vermelho 99 responded to callus formation and also direct embryogenesis in the presence of ethylene.

Adelaide Siqueira, Silva; José Magno Queiroz, Luz; Tatiana Michlovská, Rodrigues; Cecília Alves, Bittar; Leandro de Oliveira, Lino.

2011-12-01

236

Emotional response to virtual reality exposure across different cultures: the role of the attribution process.  

Science.gov (United States)

Many studies have shown the ability of media--television, movies, and virtual reality (VR) experiences--to elicit emotions. Nevertheless, it is still unclear how the different factors involved--user related and medium related--play a role in producing an emotional response during a VR experience. We investigate this issue, analyzing the role played by the cultural and technological backgrounds of the users in the emotional responses to VR. Specifically, we use the "core affect" model of emotions developed by Russell (2003) to explore how these factors influence the way in which participants experience virtual worlds. Our sample includes 20 Mexican participants: 8 living in El Tepeyac, a small rural and isolated Mexican village characterized by a very primitive culture, and 12 high civilized inhabitants of Mexico City. The "Green Valley," a noninteractive, relaxing immersive environment showing a mountain landscape around a calm lake, was used to induce relaxation in the two groups during an ambulatory surgical operation. To investigate the effects of VR on the relaxation process, we measured participants' physiological (heart rate) and emotional (VAS-A) responses before, during, and after the operation. The results show that VR significantly modified the core affect (reduced arousal) in all participants but that the final emotional response produced by this change was influenced by the attribution process: the civilized inhabitants of Mexico City, who were able to attribute the reduced arousal to the VR experience, reported a significant reduction in the self-reported level of anxiety, while people from El Tepeyac showed a reduction in their physiological reactions but not in their perceived anxiety. PMID:19886825

Gorini, Alessandra; Mosso, José Luis; Mosso, Dejanira; Pineda, Erika; Ruíz, Norma Leticia; Ramíez, Miriam; Morales, José Luis; Riva, Giuseppe

2009-12-01

237

Assessing the Impact of the National Cultural Framework on Responsible Corporate Behaviour towards Consumers: an Application of Geert Hofstede`s Cultural Model  

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Full Text Available This article aims to define and measure responsible corporate behaviour towards consumers in EU countries by defining an index of responsible corporate behaviour towards consumers and to establish the impact of Geert Hofstede's cultural dimensions on the responsible behaviour of organisations towards consumers. The index uses a specific measurement methodology based on three major components of responsible corporate behaviour towards customers and on content analysis of the Eurostat databases, the RAPEX 2012 Annual Report, the 2012-2013 Global Competitiveness Report and the Global Reporting Initiative database. We used the multifactorial regression and the Wald significance test to demonstrate that organisations operating in countries characterised by low power distance, individualism, femininity, tolerance of unknown and long-term orientation pay more attention to responsible corporate behaviour towards customers. The study highlights theoretical considerations that support the influence of the national cultural framework on responsible corporate behaviour towards consumers. The methodology for calculating the index of responsible corporate behaviour towards consumers can become a basis of analysis of responsible corporate behaviour towards local consumers or other stakeholders.

Cristina G?nescu

2014-02-01

238

The metabolic response of cultured tomato cells to low oxygen stress.  

Science.gov (United States)

The storage of fruits and vegetables under a controlled atmosphere can induce low oxygen stress, which can lead to post-harvest losses through the induction of disorders such as core breakdown and browning. To gain better understanding of the metabolic response of plant organs to low oxygen, cultured tomato cells (Lycopersicum esculentum) were used as a model system to study the metabolic stress response to low oxygen (0 and 1 kPa O2). By adding 13C labelled glucose, changes in the levels of polar metabolites and their 13C label accumulation were quantified. Low oxygen stress altered the metabolite profile of tomato cells, with the accumulation of the intermediates of glycolysis in addition to increases in lactate and sugar alcohols. 13C label data showed reduced label accumulation in almost all metabolites except lactate and some sugar alcohols. The results showed that low oxygen stress in tomato cell culture activated fermentative metabolism and sugar alcohol synthesis while inhibiting the activity of the TCA cycle and the biosynthesis of metabolites whose precursors are derived from central metabolism, including fluxes to most organic acids, amino acids and sugars. PMID:24119171

Ampofo-Asiama, J; Baiye, V M M; Hertog, M L A T M; Waelkens, E; Geeraerd, A H; Nicolai, B M

2014-05-01

239

Induction of heme oxygenase: A general response to oxidant stress in cultured mammalian cells  

Energy Technology Data Exchange (ETDEWEB)

Accumulation of heme oxygenase mRNA is strongly stimulated by treatment of cultured human skin fibroblasts with ultraviolet radiation, hydrogen peroxide, or the sulfhydryl reagent sodium arsenite. Since this will result in a transient reduction in the prooxidant state of cells, the phenomenon may represent an important inducible antioxidant defense mechanism. To examine the generality of the response, we have measured the accumulation of the specific mRNA in a variety of human and mammalian cell types after inducing treatments. Induction by sodium arsenite is observed in all additional human cell types tested. This includes primary epidermal keratinocytes and lung and colon fibroblasts as well as established cell lines such as HeLa, TK6 lymphoblastoid, and transformed fetal keratinocytes. Strong induction of heme oxygenase mRNA is also observed following sodium arsenite treatment of cell lines of rat, hamster, mouse, monkey, and marsupial origin. The agents which lead to induction in cultured human skin fibroblasts fall into two categories: (a) those which are oxidants or can generate active intermediates (ultraviolet A radiation, hydrogen peroxide, menadione, and the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate); (b) agents which are known to interact with or modify cellular glutathione levels (buthionine sulfoximine, sodium arsenite, iodoacetamide, diamide, and cadmium chloride). These observations strongly support the hypothesis that induction of the enzyme is a general response to oxidant stress in mammalian cells and are consistent with the possibility that the cellular redox state plays a key role.

Applegate, L.A.; Luscher, P.; Tyrrell, R.M. (Swiss Institute for Experimental Cancer Research, Epalinges (Switzerland))

1991-02-01

240

Induction of heme oxygenase: A general response to oxidant stress in cultured mammalian cells  

International Nuclear Information System (INIS)

Accumulation of heme oxygenase mRNA is strongly stimulated by treatment of cultured human skin fibroblasts with ultraviolet radiation, hydrogen peroxide, or the sulfhydryl reagent sodium arsenite. Since this will result in a transient reduction in the prooxidant state of cells, the phenomenon may represent an important inducible antioxidant defense mechanism. To examine the generality of the response, we have measured the accumulation of the specific mRNA in a variety of human and mammalian cell types after inducing treatments. Induction by sodium arsenite is observed in all additional human cell types tested. This includes primary epidermal keratinocytes and lung and colon fibroblasts as well as established cell lines such as HeLa, TK6 lymphoblastoid, and transformed fetal keratinocytes. Strong induction of heme oxygenase mRNA is also observed following sodium arsenite treatment of cell lines of rat, hamster, mouse, monkey, and marsupial origin. The agents which lead to induction in cultured human skin fibroblasts fall into two categories: (a) those which are oxidants or can generate active intermediates (ultraviolet A radiation, hydrogen peroxide, menadione, and the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate); (b) agents which are known to interact with or modify cellular glutathione levels (buthionine sulfoximine, sodium arsenite, iodoacetamide, diamide, and cadmium chloride). These observations strongly support the hypothesis that induction of the enzymehe hypothesis that induction of the enzyme is a general response to oxidant stress in mammalian cells and are consistent with the possibility that the cellular redox state plays a key role

 
 
 
 
241

The Korean version of the Carpal Tunnel Questionnaire. Cross cultural adaptation, reliability, validity and responsiveness.  

Science.gov (United States)

The purpose of this study was to translate and culturally adapt the Carpal Tunnel Questionnaire to produce an equivalent Korean version. A total of 53 patients completed the Korean version of the Carpal Tunnel Questionnaire pre-operatively and 3 months after open carpal tunnel release. All 53 also completed the Korean version of the Disabilities of Arm, Shoulder, and Hand questionnaire pre-operatively and 3 months post-operatively. Reliability was measured by determining the test-retest reliability and internal consistency. Test-retest reliability was assessed using intraclass correlation coefficients and paired t-tests, and internal consistency using Cronbach's alpha coefficients. Pearson correlation analysis was carried out on the Korean version of the Carpal Tunnel Questionnaire scores and the Korean version of the Disabilities of Arm, Shoulder, and Hand scores to assess construct validity. Responsiveness was evaluated using effect sizes and standardized response means. The reliability of the Korean version of the Carpal Tunnel Questionnaire was good. The scores in the Korean version of the Disabilities of Arm, Shoulder, and Hand strongly correlated with the scores in the Korean version of the Carpal Tunnel Questionnaire. Standardized response mean and effect size were both large for the Korean version of the Carpal Tunnel Questionnaire. The study shows that the Korean version of the Carpal Tunnel Questionnaire is a reliable, valid and responsive instrument for measuring outcomes in carpal tunnel syndrome. PMID:25005562

Kim, J K; Lim, H M

2015-02-01

242

Dedifferentiation of intrinsic response properties of motoneurons in organotypic cultures of the spinal cord of the adult turtle  

DEFF Research Database (Denmark)

Explant cultures from the spinal cord of adult turtles were established and used to study the sensitivity of the intrinsic response properties of motoneurons to the changes in connectivity and milieu imposed by isolation in culture. Transverse sections 700 microm thick were explanted on cover slips and maintained in roller-tube cultures in medium containing serum and the growth factors brain-derived neurotrophin factor (BDNF), neurotrophin-3 (NT3), glial cell line-derived neurotrophic factor (GDNF) and ciliary neurotrophic factor (CNTF). The gross morphology of acute sections was maintained after 4 weeks in culture. Cell bodies of motoneurons remained stainable in fixed cultures with an antibody against choline acetyltransferase (ChAT) throughout the culture period. During culture, motoneurons maintained stable resting membrane potentials and were contacted by functional synapses. The ability to generate action potentials was also preserved as was delayed inward rectification and generation of calcium spikes in the presence of tetra-ethyl ammonium (TEA). In response to depolarization, however, motoneurons presented strong outward rectification, and only 41% of the cells recorded from maintained the ability to fire repetitively. By the second week in culture, a fraction of motoneurons displayed fast and slow transient outward rectification and low-threshold calcium spikes, features not seen in turtle motoneurons in acute slices. On the other hand, properties mediated by L-type Ca2+ channels disappeared during the first few days in culture. Our observations show that the phenotypical intrinsic response properties of mature spinal motoneurons are modified in explant cultures. The properties acquired resemble the properties in juvenile motoneurons in several species of terrestrial vertebrates.

Perrier, J F; Noraberg, J

2000-01-01

243

Culture medium type affects endocytosis of multi-walled carbon nanotubes in BEAS-2B cells and subsequent biological response.  

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We examined the cytotoxicity of multi-walled carbon nanotubes (MWCNTs) and the resulting cytokine secretion in BEAS-2B cells or normal human bronchial epithelial cells (HBEpCs) in two types of culture media (Ham's F12 containing 10% FBS [Ham's F12] and serum-free growth medium [SFGM]). Cellular uptake of MWCNT was observed by fluorescent microscopy and analyzed using flow cytometry. Moreover, we evaluated whether MWCNT uptake was suppressed by 2 types of endocytosis inhibitors. We found that BEAS-2B cells cultured in Ham's F12 and HBEpCs cultured in SFGM showed similar biological responses, but BEAS-2B cells cultured in SFGM did not internalize MWCNTs, and the 50% inhibitory concentration value, i.e., the cytotoxicity, was increased by more than 10-fold. MWCNT uptake was suppressed by a clathrin-mediated endocytosis inhibitor and a caveolae-mediated endocytosis inhibitor in BEAS-2B cells cultured in Ham's F12 and HBEpCs cultured in SFGM. In conclusion, we suggest that BEAS-2B cells cultured in a medium containing serum should be used for the safety evaluation of nanomaterials as a model of normal human bronchial epithelial cells. However, the culture medium composition may affect the proteins that are expressed on the cytoplasmic membrane, which may influence the biological response to MWCNTs. PMID:23648666

Haniu, Hisao; Saito, Naoto; Matsuda, Yoshikazu; Tsukahara, Tamotsu; Maruyama, Kayo; Usui, Yuki; Aoki, Kaoru; Takanashi, Seiji; Kobayashi, Shinsuke; Nomura, Hiroki; Okamoto, Masanori; Shimizu, Masayuki; Kato, Hiroyuki

2013-09-01

244

Molecular analysis of chondrocytes cultured in agarose in response to dynamic compression  

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Full Text Available Abstract Background Articular cartilage is exposed to high mechanical loads under normal physiological conditions and articular chondrocytes regulate the composition of cartilaginous matrix, in response to mechanical signals. However, the intracellular pathways involved in mechanotransduction are still being defined. Using the well-characterized chondrocyte/agarose model system and dynamic compression, we report protocols for preparing and characterizing constructs of murine chondrocytes and agarose, and analyzing the effect of compression on steady-state level of mRNA by RT-PCR, gene transcription by gene reporter assay, and phosphorylation state of signalling molecules by Western-blotting. The mouse model is of particular interest because of the availability of a large choice of bio-molecular tools suitable to study it, as well as genetically modified mice. Results Chondrocytes cultured in agarose for one week were surrounded by a newly synthesized pericellular matrix, as revealed by immunohistochemistry prior to compression experiments. This observation indicates that this model system is suitable to study the role of matrix molecules and trans-membrane receptors in cellular responsiveness to mechanical stress. The chondrocyte/agarose constructs were then submitted to dynamic compression with FX-4000C™ Flexercell® Compression Plus™ System (Flexcell. After clearing proteins off agarose, Western-blotting analysis showed transient activation of Mitogen-activated protein kinases (MAPK in response to dynamic compression. After assessment by capillary electrophoresis of the quality of RNA extracted from agarose, steady-state levels of mRNA expression was measured by real time PCR. We observed an up-regulation of cFos and cJun mRNA levels as a response to compression, in accordance with the mechanosensitive character observed for these two genes in other studies using cartilage explants submitted to compression. To explore further the biological response of mouse chondrocytes to the dynamic compression at the transcriptional level, we also developed an approach for monitoring changes in gene transcription in agarose culture by using reporter promoter constructs. A decrease in promoter activity of the gene coding for type II procollagen, the most abundant protein in cartilage, was observed in response to dynamic loading. Conclusion The protocols developed here offer the possibility to perform an integrated analysis of the molecular mechanisms of mechanotransduction in chondrocytes, at the gene and protein level.

Mallein-Gerin Frédéric

2008-09-01

245

Maize csmd1 exhibits pre-meiotic somatic and post-meiotic microspore and somatic defects but sustains anther growth.  

Science.gov (United States)

Maize male reproductive development is complex and lengthy, and anther formation and pollen maturation are precisely and spatiotemporally regulated. Here, we document that callose, somatic, and microspore defect 1 (csmd1), a new male-sterile mutant, has both pre-meiotic somatic and post-meiotic gametophyte and somatic defects. Chromosome behavior and cell developmental events were monitored by nuclear staining viewed by bright field microscopy; cell dimensions were charted by Volocity analysis of confocal microscopy images. Aniline blue staining and quantitative assays were performed to record callose deposition, and expression of three callose synthase genes was measured by qRT-PCR. Despite numerous defects and unlike other maize male-sterile mutants that show growth arrest coincident with locular defects, csmd1 anther elongation is nearly normal. Pre-meiotically and during prophase I, there is excess callose surrounding the meiocytes. Post-meiotically csmd1 epidermal cells have impaired elongation but excess longitudinal divisions, and uninucleate microspores cease growth; the microspore nucleoli degrade followed by cytoplasmic vacuolization and haploid cell collapse. The single vascular bundle within csmd1 anthers senesces precociously, coordinate with microspore death. Although csmd1 anther locules contain only epidermal and endothecial cells at maturity, locules are oval rather than collapsed, indicating that these two cell types suffice to maintain an open channel within each locule. Our data indicate that csmd1 encodes a crucial factor important for normal anther development in both somatic and haploid cells, that excess callose deposition does not cause meiotic arrest, and that developing pollen is not required for continued maize anther growth. PMID:21475967

Wang, Dongxue; Skibbe, David S; Walbot, Virginia

2011-12-01

246

The unfolded protein response to endoplasmic reticulum stress in cultured astrocytes and rat brain during experimental diabetes  

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Oxidative-nitrosative stress and inflammatory responses are associated with endoplasmic reticulum (ER) stress in diabetic retinopathy, raising the possibility that disturbances in ER protein processing may contribute to CNS dysfunction in diabetics. Upregulation of the unfolded protein response (UPR) is a homeostatic response to accumulation of abnormal proteins in the ER, and the present study tested the hypothesis that the UPR is upregulated in two models for diabetes, cultured astrocytes g...

Lind, Katrine R.; Ball, Kelly K.; Cruz, Nancy F.; Dienel, Gerald A.

2013-01-01

247

Studies in tissue culture of some indigenous rice (Oryza glaberrima Steud.) accessions in Ghana  

International Nuclear Information System (INIS)

A study was conducted with the aim of developing separate protocols for callus induction and plant regeneration from different parts of three O. glaberrima accessions indigenous to Ghana. The three O. glaberrima accessions, Guame, N/4 and SARI 1 were assessed for their callus induction and plant regeneration ability from leaf segments, mature dehusked seeds and anthers on different concentrations of plant growth regulators, incorporated into Murashige and Skoog, (1962) (MS) basal medium. For leaf segments, callus was induced on MS supplemented with (0-10) mg/l 2,4-D. Callus induction frequency was significantly (p?0.05) different among accessions, as well as among the 2,4-dichlorophenoxyacetic acid (2,4-D) levels tested. Highest callus induction frequency was exhibited at a concentration of 6 mg/l 2,4-D for all accessions tested. Callus obtained was sub-cultured on regeneration medium consisting of MS supplemented with (1:0-5) mg.l NAA:BAP. Plant regeneration was nil. Instead, prolific root formation was observed. For mature dehusked seeds, callus induction medium consisted of MS supplemented with (0-6) mg/l 2,4-D. All tested accessions exhibited highest callus frequency at 4 mg/l 2,4-D. Similarly callus induction frequency was significantly (p?0.05) different among accessions, as well as among concentrations of 2,4-D tested. Calli obtained were sub-cultured on MS medium supplemented with (0-2.5) mg/l 6-benzylaminopurine (BAP) and exhibited the highest regeneratio and exhibited the highest regeneration frequency on medium containing 2.0 mg/l BAP. However, callus induced on a concentration of 3 mg/l 2,4-D and sub-cultured on a concentration of 2 mg/l BAP gave the best response n terms of shoot proliferation, growth and root development and therefore were considered to be the optimum concentrations for callus induction and plant regeneration respectively. Plantlet regeneration was achieved only in accession N/4 while Guame and SARI 1 exhibited poor regeneration response. Among the three rice accessions evaluated, N/4 was the most promising accession in terms of callus induction frequency and regeneration ability. The three accessions of O. glaberrima were again studied for their response to anther culture in terms of callus induction and frequency of plant regeneration using N, Garfish and D oy, MS and Nis tch tissue culture media, and supplemented with 2,4-D (1:(0-5) mg/l) were used for callus induction. No response to callus formation was obtained after 16 weeks of culture and a conclusion was drawn that all three accessions were recalcitrant to anther culture. (au)

248

Education to promote culturally competent nursing care--a content analysis of student responses.  

Science.gov (United States)

The aim of this study was to describe and analyse the outcome of a 3-year study program from a student perspective for the purpose of promoting culturally congruent nursing care. Students were asked to complete questionnaires that included cases with open-ended questions at the beginning and end of the 3-year program. Two nursing situations were described and the students had to imagine how they would act in such cases. Ninety-two students completed the two questionnaires and the result of a manifest content analysis of their answers is presented. Four categories were formulated from the content analysis; an inviting attitude, a non-inviting attitude, a knowledge-driven attitude and a non-knowledge-driven attitude. An inviting attitude meant that the students found different strategies for approaching the patient and his/her spouse or parent. A non-inviting attitude implied that the students became frustrated with the situation and had more difficulty finding solutions that would enhance the relationship. A knowledge-driven attitude meant that the students described how they found it important to base nursing actions on knowledge of the patient. A non-knowledge-driven attitude meant that the students' responses indicated that they did not consider knowledge to be the foundation of their nursing actions. The study demonstrates marked changes in the students' approaches to culturally sensitive issues at the end of the education program. PMID:19581027

Gebru, Kerstin; Willman, Ania

2010-01-01

249

Cellular immune response to Mycobacterium tuberculosis-specific antigen culture filtrate protein-10 in south India.  

Science.gov (United States)

The Mycobacterium tuberculosis (M. tuberculosis)-specific culture filtrate protein-10 (CFP-10) is highly recognized by M. tuberculosis infected subjects. In the present study, the proliferative response and IFN-gamma secretion was found for C-terminal peptides of the protein (Cfp6(51-70), Cfp7(61-80), Cfp8(71-90), and Cfp9(81-100)). The alleles HLA DRB1 *04 and HLA DRB1 *10 recognized the C-terminal peptides Cfp7, Cfp8, and Cfp9 in HHC. Cfp6 was predominantly recognized by the alleles HLA DRB1 *03 and HLA DRB1 *15 by PTB. The minimal nonameric epitopes from the C-terminal region were CFP-10(56-64) and CFP-10(76-84). These two peptides deserve attention for inclusion in a vaccine against tuberculosis in this region. PMID:19902247

Kumar, Madhan; Sundaramurthi, Jagadish C; Mehra, Narinder K; Kaur, Gurvinder; Raja, Alamelu

2010-02-01

250

Response of cultured IEC-17 normal rat intestinal epithelial cells to x radiation  

International Nuclear Information System (INIS)

The growth parameters and radiosensitivity of normal rat intestinal epithelial cells, IEC-17, were studied. The cells were cultured by standard methods and exposed to an array of doses (1-12 Gy) of 250 kVp X rays. The survival curves generated exhibited no initial shoulder and were bimodal. The D0 of the first component was about 0.2 Gy and the second component, 5.0 Gy. The ability of this cell line to repair sublethal lesions was examined by fractionation studies; repair was completed within 60 min after the first dose. The survival curves obtained for the IEC-17 cell line are consistent with the response of a morphologically distinct single population containing two functionally separate types of cells

251

Initiating Culturally Responsive Teaching for Identity Construction in the Malaysian Classrooms  

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Full Text Available This article presents evidence to the need for Culturally Responsive Teaching (CRT to construct students’ identity in the Malaysian classrooms. Since an important objective of education is to prepare individuals to exercise efficaciously in their environment, all students in multicultural society could benefit from exposure to CRT (Gay, 2000. In this study, a specific text (Ah Khaw Goes to Heaven was used in the English literature classroom, which depicted conflicts in multicultural Malaya in the 1940s. A qualitative inquiry employing semi-structured, in depth interviews with 9 English language teachers in 6 schools around Kuala Lumpur were carried out. Classroom observations were conducted, and group interviews with 6 groups of students were also carried out. Thematic analysis were performed and the findings suggest that students’ interpretation of CRT were influenced by an orthodox perception of their identity in the classroom and in the teaching and learning process, while teachers were more skeptical and reserved in developing CRT.

Faizah Idrus

2014-03-01

252

High responsiveness of cytosolic free calcium concentration to angiotensin II in cultured pulmonary arterial myocytes from pulmonary hypertensive rats.  

Science.gov (United States)

Pulmonary arterial myocytes were cultured from normotensive and pulmonary hypertensive rats. Microfluorimetry of Ca2+ signals in fluo-3-loaded single myocytes at day 7 of culture was performed by a laser-scanned confocal imaging system. The resting level of cytoplasmic Ca2+ concentration ([Ca2+]i) in vascular myocytes obtained from hypertensive rats was higher than that in cultured myocytes obtained from normotensive rats. Angiotensin II elevated [Ca2+]i in the vascular myocytes cultured from both normotensive and hypertensive rats. However, a rise of [Ca2+]i induced by angiotensin II in the vascular myocytes obtained from pulmonary hypertensive rats was higher than that obtained from normotensive rats. On the other hand, the response of [Ca2+]i to A23187 did not differ between the vascular myocytes cultured from normotensive and hypertensive rats. The present results suggest that the resting and angiotensin II-responsive levels of [Ca2+]i in pulmonary arterial myocytes cultured from pulmonary hypertensive rats are higher than those cultured from normotensive rats. PMID:9344225

Li, Z; Zhang, Q; Zhao, S; Wei, M; Cong, H; Ouda, H; Odajima, K; Takemura, H

1997-08-01

253

In vitro androgenetic cultures of Hyoscyamus niger L., H. albus L. and alkaloid content assay  

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Full Text Available In vitro cultures of Hyoscyamus niger L. and H. albus L. anthers were initiated which resulted in obtaining androgenectic plants and callus cultures. The leaves of these pants and the callus cultures were subjected to analysis (TLC, GC for the presence of alkaloids, derivatives of tropane. In the studied material, alkaloids of different qualitative and quantitative composition from that of ground-grown plants were found.

Maria Weso?wska

1985-03-01

254

Development and use of culture systems to modulate specific cell responses  

Science.gov (United States)

Culture surfaces that induce specific localized cell responses are required to achieve tissue-like cell growth in three-dimensional (3D) environments, as well as to develop more efficient cell-based diagnostic techniques, noticeably when working with fragile cells such as stem cells or platelets. As such, Chapter 1 of this thesis work is devoted to the review of 3D cell-material interactions in vitro and the corresponding existing culture systems available to achieve in vivo-like cell responses. More adequate 3D culture systems will need to be developed to mimic several characteristics of in vivo environments, including lowered non-specific cell-material interactions and localized biochemical signaling. The experimental work in this thesis is based on the hypothesis that well-studied and optimized surface treatments will be able to lower non-specific cell-material interactions and allow local chemical modification in order to achieve specific localized cell-material interactions for different applications. As such, in Chapter 2 and Chapter 3 of this thesis, surface treatments were developed using plasma polymerization and covalent immobilization of a low-fouling polymer (i.e., poly(ethylene glycol)) and characterized and optimized using a large number of techniques including atomic force microscopy, quartz crystal microbalance, surface plasmon resonance, x-ray photoelectron spectroscopy and fluorescence-based techniques. The main plasma polymerization parameter important for surface chemical content, specifically nitrogen to carbon content, was identified as being glow discharge power, while reaction time and power determined plasma film thickness. Moreover, plasma films were shown to be stable in aqueous environments. Covalently-bound poly(ethylene glycol) (PEG) layers physicochemical and mechanical properties are dependent on fabrication methods. Polymer concentration in solution is an important indicator of final layer properties, and use of a theta solvent induces complex aggregation phenomena in solution yielding layers with widely different properties. Chemically available primary amine groups are also shown to be present, paving the way for the immobilization of bio-active molecules. An application of low-fouling locally modified surfaces is given in Chapter 4 by the development of a novel diagnostic surface to evaluate platelet activation which is until now very difficult as platelets are readily activated by in vitro manipulations. Significant results from volunteer donors indicate that this diagnostic instrument has the potential to allow the rapid estimation of platelet activation levels in whole blood.

Martin, Yves

255

Distribution of the anther-smut pathogen Microbotryum on species of the Caryophyllaceae.  

Science.gov (United States)

*Understanding disease distributions is of fundamental and applied importance, yet few studies benefit from integrating broad sampling with ecological and phylogenetic data. Here, anther-smut disease, caused by the fungus Microbotryum, was assessed using herbarium specimens of Silene and allied genera of the Caryophyllaceae. *A total of 42,000 herbarium specimens were examined, and plant geographical distributions and morphological and life history characteristics were tested as correlates of disease occurrence. Phylogenetic comparative methods were used to determine the association between disease and plant life-span. *Disease was found on 391 herbarium specimens from 114 species and all continents with native Silene. Anther smut occurred exclusively on perennial plants, consistent with the pathogen requiring living hosts to overwinter. The disease was estimated to occur in 80% of perennial species of Silene and allied genera. The correlation between plant life-span and disease was highly significant while controlling for the plant phylogeny, but the disease was not correlated with differences in floral morphology. *Using resources available in natural history collections, this study illustrates how disease distribution can be determined, not by restriction to a clade of susceptible hosts or to a limited geographical region, but by association with host life-span, a trait that has undergone frequent evolutionary transitions. PMID:20406409

Hood, Michael E; Mena-Alí, Jorge I; Gibson, Amanda K; Oxelman, Bengt; Giraud, Tatiana; Yockteng, Roxana; Arroyo, Mary T K; Conti, Fabio; Pedersen, Amy B; Gladieux, Pierre; Antonovics, Janis

2010-07-01

256

The presence of a culturally similar or dissimilar social partner affects neural responses to emotional stimuli  

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Full Text Available Background: Emotional responding is sensitive to social context; however, little emphasis has been placed on the mechanisms by which social context effects changes in emotional responding. Objective: We aimed to investigate the effects of social context on neural responses to emotional stimuli to inform on the mechanisms underpinning context-linked changes in emotional responding. Design: We measured event-related potential (ERP components known to index specific emotion processes and self-reports of explicit emotion regulation strategies and emotional arousal. Female Chinese university students observed positive, negative, and neutral photographs, whilst alone or accompanied by a culturally similar (Chinese or dissimilar researcher (British. Results: There was a reduction in the positive versus neutral differential N1 amplitude (indexing attentional capture by positive stimuli in the dissimilar relative to alone context. In this context, there was also a corresponding increase in amplitude of a frontal late positive potential (LPP component (indexing engagement of cognitive control resources. In the similar relative to alone context, these effects on differential N1 and frontal LPP amplitudes were less pronounced, but there was an additional decrease in the amplitude of a parietal LPP component (indexing motivational relevance in response to positive stimuli. In response to negative stimuli, the differential N1 component was increased in the similar relative to dissimilar and alone (trend context. Conclusion: These data suggest that neural processes engaged in response to emotional stimuli are modulated by social context. Possible mechanisms for the social-context-linked changes in attentional capture by emotional stimuli include a context-directed modulation of the focus of attention, or an altered interpretation of the emotional stimuli based on additional information proportioned by the context.

Kate A. Woodcock

2013-06-01

257

Transient responses of nitrogenase to acetylene and oxygen in actinorhizal nodules and cultured Frania  

Energy Technology Data Exchange (ETDEWEB)

Nitrogenase activity in root nodules of four species of actinorhizal plants showed varying declines in response to exposure to acetylene (10% v/v). Gymnostoma papuanum (S.Moore) L. Johnson. and Casuarina equisetifolia L. nodules showed a small decline (5-15%) with little or no recovery over 15 minutes. Myrica gale L. nodules showed a sharp decline followed by a rapid return to peak activity. Alnus incana ssp. rugosa (Du Roi) Clausen. nodules usually showed varying degrees of decline followed by a slower return to peak or near-peak activity. We call these effects acetylene-induced transients. Rapid increases in oxygen tension also caused dramatic transient decreases in nitrogenase activity in all species. The magnitude of the transient decrease was related to the size of the O{sub 2} partial pressure (pO{sub 2}) rise, to the proximity of the starting and ending oxygen tensions to the pO{sub 2} optimum, and to the time for which the plant was exposed to the lower pO{sub 2}. Oxygen-induced transients, induced both by step jumps in pO{sub 2} and by O{sub 2} pulses, were also observed in cultures of Frankia. The effects seen in nodules are purely a response by the bacterium and not a nodule effect per se. Oxygen-induced nitrogenase transients in actinorhizal nodules from the plant genera tested here do not appear to be a result of changes in nodule diffusion resistance.

Silvester, W.B.; Winship, L.J. (Harvard Univ., Petersham, MA (USA))

1990-02-01

258

An Evaluation Of Response Scale Formats Of The Culture Assessment Instrument  

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Full Text Available The aim of the study was to investigate which response scale, of the four, five, or six-point response scales would yield the best metric properties on the Culture Assessment Instrument. This was achieved by utilising data sets where the respective scales were used. The subjects included participants of various organisations, ages, educational levels, language and gender groups. No one scale could be identified as having the better metric properties. The lack of conclusive results is attributed to differences in education, aggregation effect, possibility of different units of measurement being measured and the manner in which Cronbach Alpha is calculated Opsomming
Die doel van die studie was om vas te stel watter responsskaal, van ‘n vier-, vyf-, of sespuntskaal die beste metriese eienskappe sou oplewer op die Kultuurtakseringinstrument. Dit is bereik, deur gebruik te maak van datastelle waar die skale toegepas is. Deelnemers was afkomstig uit verskeie organsisasies, ouderdomsgroepe, opvoedkundige agtergronde, taalgroepe en geslagte. Geen skaal kon gëidentifiseer word met onderskeidende metriese eienskappe nie. Die gebrek aan beduidende resultate word toegeskryf aan die verskille in die opvoedkundige agtergronde van deelnemers, samevoegingseffek, die moonlikheid van verskillende eenhede van meting en die wyse waarop Cronbach Alpha bereken is.

Gert Roodt

2003-11-01

259

Construção e avaliação de um protótipo de máquina coletora de anteras / Construction and evaluation of an anther collector prototype machine  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Um protótipo de máquina coletora de anteras foi projetado e construído, e seu desempenho foi avaliado, comparando - se com o método de coleta manual, em flores rosáceas e campanuladas de pessegueiro (Prunus persica). O trabalho foi conduzido utilizando-se do delineamento experimental inteiramente ao [...] acaso, arranjado em um esquema bifatorial (2 métodos de remoção x 2 formas florais), com 12 repetições de 30 balões florais. O protótipo apresentou maior velocidade de processamento, sem diminuir a qualidade do pólen, mesmo sendo armazenadas anteras com maior quantidade de filetes e descartado maior número de anteras do que o método manual. Abstract in english An anther collector prototype machine was projected and built. Its performance was evaluated by comparisons between the use of the prototype and the traditional manual method, both for showy and non-showy peach-tree flowers (Prunus persica). The study was accomplished in August 2011 using a complete [...] ly randomized experimental design, arranged in a bi-factorial scheme (2 collection methods x 2 flower forms), with 12 repetitions, each consisted by 30 flowers. The prototype proved to be faster in the anther extraction time without losses in the pollen quality, even harvesting anthers with higher fillet amounts and discarding a higher quantity of anthers than the manual method.

Rodrigo, Tonet; Marcos Robson, Sachet; Idemir, Citadin; Alcir José, Modolo.

2013-03-01

260

OsATG7 is required for autophagy-dependent lipid metabolism in rice postmeiotic anther development.  

Science.gov (United States)

In flowering plants, the tapetum, the innermost layer of the anther, provides both nutrient and lipid components to developing microspores, pollen grains, and the pollen coat. Though the programmed cell death of the tapetum is one of the most critical and sensitive steps for fertility and is affected by various environmental stresses, its regulatory mechanisms remain mostly unknown. Here we show that autophagy is required for the metabolic regulation and nutrient supply in anthers and that autophagic degradation within tapetum cells is essential for postmeiotic anther development in rice. Autophagosome-like structures and several vacuole-enclosed lipid bodies were observed in postmeiotic tapetum cells specifically at the uninucleate stage during pollen development, which were completely abolished in a retrotransposon-insertional OsATG7 (autophagy-related 7)-knockout mutant defective in autophagy, suggesting that autophagy is induced in tapetum cells. Surprisingly, the mutant showed complete sporophytic male sterility, failed to accumulate lipidic and starch components in pollen grains at the flowering stage, showed reduced pollen germination activity, and had limited anther dehiscence. Lipidomic analyses suggested impairment of editing of phosphatidylcholines and lipid desaturation in the mutant during pollen maturation. These results indicate a critical involvement of autophagy in a reproductive developmental process of rice, and shed light on the novel autophagy-mediated regulation of lipid metabolism in eukaryotic cells. PMID:24674921

Kurusu, Takamitsu; Koyano, Tomoko; Hanamata, Shigeru; Kubo, Takahiko; Noguchi, Yuhei; Yagi, Chikako; Nagata, Noriko; Yamamoto, Takashi; Ohnishi, Takayuki; Okazaki, Yozo; Kitahata, Nobutaka; Ando, Daichi; Ishikawa, Masaya; Wada, Shinya; Miyao, Akio; Hirochika, Hirohiko; Shimada, Hiroaki; Makino, Amane; Saito, Kazuki; Ishida, Hiroyuki; Kinoshita, Tetsu; Kurata, Nori; Kuchitsu, Kazuyuki

2014-05-01

 
 
 
 
261

Construção e avaliação de um protótipo de máquina coletora de anteras Construction and evaluation of an anther collector prototype machine  

Directory of Open Access Journals (Sweden)

Full Text Available Um protótipo de máquina coletora de anteras foi projetado e construído, e seu desempenho foi avaliado, comparando - se com o método de coleta manual, em flores rosáceas e campanuladas de pessegueiro (Prunus persica. O trabalho foi conduzido utilizando-se do delineamento experimental inteiramente ao acaso, arranjado em um esquema bifatorial (2 métodos de remoção x 2 formas florais, com 12 repetições de 30 balões florais. O protótipo apresentou maior velocidade de processamento, sem diminuir a qualidade do pólen, mesmo sendo armazenadas anteras com maior quantidade de filetes e descartado maior número de anteras do que o método manual.An anther collector prototype machine was projected and built. Its performance was evaluated by comparisons between the use of the prototype and the traditional manual method, both for showy and non-showy peach-tree flowers (Prunus persica. The study was accomplished in August 2011 using a completely randomized experimental design, arranged in a bi-factorial scheme (2 collection methods x 2 flower forms, with 12 repetitions, each consisted by 30 flowers. The prototype proved to be faster in the anther extraction time without losses in the pollen quality, even harvesting anthers with higher fillet amounts and discarding a higher quantity of anthers than the manual method.

Rodrigo Tonet

2013-03-01

262

The effects of intestinal LPS exposure on inflammatory responses in a porcine enterohepatic co-culture system.  

Science.gov (United States)

A porcine enterohepatic co-culture system, with primary hepatocytes as bottom layer and IPEC-J2 epithelial cells as upper layer, was developed to study the effects of lipopolysaccharides (LPS) on the gene expression profile of pro-inflammatory cytokines (interleukin-8 (IL-8) and tumor necrosis factor-?) and CYP enzymes (CYP1A1, CYP1A2, CYP3A29). The barrier integrity of IPEC-J2 cells was investigated by transepithelial electrical resistance measurements and by fluorescein isothiocyanate-dextran-based test. Basolateral IL-8 production was significantly elevated in LPS-treated IPEC-J2 and primary hepatocyte mono-cultures as well as in the co-culture system, in a dose-independent manner. The LPS-induced changes in the expression of the CYP1A2 and CYP3A29 genes in hepatocyte mono-cultures differed from those in co-culture after LPS treatment on the apical side of the IPEC-J2 cell layer. CYP1A2 was downregulated by the LPS treatment in mono-cultures but upregulated at 10 ?g/ml LPS in co-culture; gene expression of CYP3A29 showed no significant LPS-induced change in the hepatocyte mono-culture but was significantly downregulated in co-culture. The newly established co-culture system capable of mimicking enterohepatic interplay in LPS-induced inflammatory responses in vitro can be used in the future for reliable screening of potential anti-inflammatory compounds. PMID:24049015

Paszti-Gere, Erzsebet; Matis, Gabor; Farkas, Orsolya; Kulcsar, Anna; Palocz, Orsolya; Csiko, Gyorgy; Neogrady, Zsuzsanna; Galfi, Peter

2014-02-01

263

Dose–response analysis of phthalate effects on gene expression in rat whole embryo culture  

International Nuclear Information System (INIS)

The rat postimplantation whole embryo culture (WEC) model serves as a potential screening tool for developmental toxicity. In this model, cultured rat embryos are exposed during early embryogenesis and evaluated for morphological effects. The integration of molecular-based markers may lead to improved objectivity, sensitivity and predictability of WEC in assessing developmental toxic properties of compounds. In this study, we investigated the concentration-dependent effects of two phthalates differing in potency, mono(2-ethylhexyl) phthalate (MEHP) and monomethyl phthalate (MMP, less toxic), on the transcriptome in WEC to examine gene expression in relation with dysmorphogenesis. MEHP was more potent than MMP in inducing gene expression changes as well as changes on morphology. MEHP induced significant enrichment of cholesterol/lipid/steroid (CLS) metabolism and apoptosis pathways which was associated with developmental toxicity. Regulation of genes within CLS metabolism pathways represented the most sensitive markers of MEHP exposure, more sensitive than classical morphological endpoints. As shown in direct comparisons with toxicogenomic in vivo studies, alterations in the regulation of CLS metabolism pathways has been previously identified to be associated with developmental toxicity due to phthalate exposure in utero. Our results support the application of WEC as a model to examine relative phthalate potency through gene expression and morphological responses. Additionally, our results further define the applicability domain of the WEC model for developmental toxicological investigations. -- Highlights: ? We examine the effect of two phthalates on gene expression and morphology in WEC. ? MEHP is more potent than MMP in inducing gene expression changes and dysmorphogenesis. ? MEHP significantly disrupts cholesterol metabolism pathways in a dose-dependent manner. ? Specific phthalate-related mechanisms in WEC are relevant to mechanisms in vivo.

264

Dose–response analysis of phthalate effects on gene expression in rat whole embryo culture  

Energy Technology Data Exchange (ETDEWEB)

The rat postimplantation whole embryo culture (WEC) model serves as a potential screening tool for developmental toxicity. In this model, cultured rat embryos are exposed during early embryogenesis and evaluated for morphological effects. The integration of molecular-based markers may lead to improved objectivity, sensitivity and predictability of WEC in assessing developmental toxic properties of compounds. In this study, we investigated the concentration-dependent effects of two phthalates differing in potency, mono(2-ethylhexyl) phthalate (MEHP) and monomethyl phthalate (MMP, less toxic), on the transcriptome in WEC to examine gene expression in relation with dysmorphogenesis. MEHP was more potent than MMP in inducing gene expression changes as well as changes on morphology. MEHP induced significant enrichment of cholesterol/lipid/steroid (CLS) metabolism and apoptosis pathways which was associated with developmental toxicity. Regulation of genes within CLS metabolism pathways represented the most sensitive markers of MEHP exposure, more sensitive than classical morphological endpoints. As shown in direct comparisons with toxicogenomic in vivo studies, alterations in the regulation of CLS metabolism pathways has been previously identified to be associated with developmental toxicity due to phthalate exposure in utero. Our results support the application of WEC as a model to examine relative phthalate potency through gene expression and morphological responses. Additionally, our results further define the applicability domain of the WEC model for developmental toxicological investigations. -- Highlights: ? We examine the effect of two phthalates on gene expression and morphology in WEC. ? MEHP is more potent than MMP in inducing gene expression changes and dysmorphogenesis. ? MEHP significantly disrupts cholesterol metabolism pathways in a dose-dependent manner. ? Specific phthalate-related mechanisms in WEC are relevant to mechanisms in vivo.

Robinson, Joshua F. [National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Verhoef, Aart; Beelen, Vincent A. van; Pennings, Jeroen L.A. [National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Piersma, Aldert H., E-mail: aldert.piersma@rivm.nl [National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Institute for Risk Assessment Sciences (IRAS), Utrecht University, Utrecht (Netherlands)

2012-10-01

265

Variability of in vitro culture response in wheat genotypes, genotype and environmental effects  

Directory of Open Access Journals (Sweden)

Full Text Available The tissue culture response (TCR of immature embryos, evaluated according to callus formation, percentage of regenerative green-spotted calli and the number of plants per embryo, was investigated in 96 wheat genotypes of worldwide origins. Immature embryos were collected 12-15 DAP from field-grown plants during three successive years 2003, 2004 and 2005. Year 2003 was with high air temperatures and tropical days during a period of vegetation, while the environmental conditions were more favorable for plant growth in the next two years, 2004 and 2005. Embryos were cultured on standard MS medium containing 2 mg l-1 2, 4-D. In all genotypes calli were efficiently induced, ranging from 36.7 to 100% (2003, 68.4 to 100% (2004, and 94.3 to 100% (2005. The calli occasionally formed green spots, but frequencies markedly differed among genotypes that varied from 0 to 72.5% (2003, 0 to 97.9% (2004, and 0 to 94.0% (2005. Coefficient of variation was highest in term of percent of regenerative calli (66.7% following by a number of plants per embryo (35.6% and callus formation (5.1%. Components of phenotypic variance showed that factor year (71.4% had the highest impact on expression of callus formation, genetic factor (47,1% on percentage of regenerative green-spotted calli and interaction year/genotype (30.3% on number of plants per embryo. The results indicated factor genotype as the most important for determining regeneration potential in wheat.

Miti? Nevena

2006-01-01

266

Dynamic culture substrate that captures a specific extracellular matrix protein in response to light  

Directory of Open Access Journals (Sweden)

Full Text Available The development of methods for the off–on switching of immobilization or presentation of cell-adhesive peptides and proteins during cell culture is important because such surfaces are useful for the analysis of the dynamic processes of cell adhesion and migration. This paper describes a chemically functionalized gold substrate that captures a genetically tagged extracellular matrix protein in response to light. The substrate was composed of mixed self-assembled monolayers (SAMs of three disulfide compounds containing (i a photocleavable poly(ethylene glycol (PEG, (ii nitrilotriacetic acid (NTA and (iii hepta(ethylene glycol (EG7. Although the NTA group has an intrinsic high affinity for oligohistidine tag (His-tag sequences in its Ni2+-ion complex, the interaction was suppressed by the steric hindrance of coexisting PEG on the substrate surface. Upon photoirradiation of the substrate to release the PEG chain from the surface, this interaction became possible and hence the protein was captured at the irradiated regions, while keeping the non-specific adsorption of non-His-tagged proteins blocked by the EG7 underbrush. In this way, we selectively immobilized a His-tagged fibronectin fragment (FNIII7–10 to the irradiated regions. In contrast, when bovine serum albumin—a major serum protein—was added as a non-His-tagged protein, the surface did not permit its capture, with or without irradiation. In agreement with these results, cells were selectively attached to the irradiated patterns only when a His-tagged FNIII7-10 was added to the medium. These results indicate that the present method is useful for studying the cellular behavior on the specific extracellular matrix protein in cell-culturing environments.

Jun Nakanishi, Hidekazu Nakayama, Kazuo Yamaguchi, Andres J Garcia and Yasuhiro Horiike

2011-01-01

267

Response of peripheral blood mononuclear cells to conditioned medium from cultured oral squamous cell carcinomas  

Directory of Open Access Journals (Sweden)

Full Text Available The current study investigated the capacity for tumor factors secreted by head and neck squamous cell carcinoma (HNSCC cell lines, KB, KB16, and HEP, to induce the secretion of various cytokines from peripheral blood mononuclear cells (PBMCs. PBMCs were isolated from blood samples collected from six healthy volunteers and these cells were incubated for 6, 24, 48, or 72 hours in the presence of 50% conditioned medium collected from cultured cell lines pretreated with, or without, stimulants such as phytohemagglutinin (PHA or lipopolysaccharides (LPS. Aliquots of each supernatant were then assayed for levels of IFN-?, vascular endothelial growth factor (VEGF, TNF-?, and IL-4 using enzyme linked immunosorbent assays (ELISAs. Data collected were analyzed using Student's t-test, an ANOVA test followed by Tukey's test, and tests of Pearson's Correlation. PBMCs cultured with KB16-conditioned medium produced the highest levels of IFN-?. VEGF was also detected in conditioned media collected from all of the squamous cell carcinoma (SCC cell lines used, and a significant difference in VEGF levels between control and KB- or KB16-conditioned media was observed. TNF-? was secreted by all PBMC groups within 6 hours of receiving conditioned media, and these levels increased up to the 24 hour timepoint, after which levels of TNF-? stabilized. In contrast, none of the supernatant samples contained detectable levels of IL-4. In combination, these data suggest that direct contact between fresh human PBMCs and conditioned media from tumor cells induces the secretion of TNF-? and VEGF by PBMCs, and this represents an initial angiogenic response.

Cristiane Miranda França

2011-10-01

268

Response of peripheral blood mononuclear cells to conditioned medium from cultured oral squamous cell carcinomas  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The current study investigated the capacity for tumor factors secreted by head and neck squamous cell carcinoma (HNSCC) cell lines, KB, KB16, and HEP, to induce the secretion of various cytokines from peripheral blood mononuclear cells (PBMCs). PBMCs were isolated from blood samples collected from s [...] ix healthy volunteers and these cells were incubated for 6, 24, 48, or 72 hours in the presence of 50% conditioned medium collected from cultured cell lines pretreated with, or without, stimulants such as phytohemagglutinin (PHA) or lipopolysaccharides (LPS). Aliquots of each supernatant were then assayed for levels of IFN-?, vascular endothelial growth factor (VEGF), TNF-?, and IL-4 using enzyme linked immunosorbent assays (ELISAs). Data collected were analyzed using Student's t-test, an ANOVA test followed by Tukey's test, and tests of Pearson's Correlation. PBMCs cultured with KB16-conditioned medium produced the highest levels of IFN-?. VEGF was also detected in conditioned media collected from all of the squamous cell carcinoma (SCC) cell lines used, and a significant difference in VEGF levels between control and KB- or KB16-conditioned media was observed. TNF-? was secreted by all PBMC groups within 6 hours of receiving conditioned media, and these levels increased up to the 24 hour timepoint, after which levels of TNF-? stabilized. In contrast, none of the supernatant samples contained detectable levels of IL-4. In combination, these data suggest that direct contact between fresh human PBMCs and conditioned media from tumor cells induces the secretion of TNF-? and VEGF by PBMCs, and this represents an initial angiogenic response.

Cristiane Miranda, França; Fabiana Mesquita, Barros; Monica Andrade, Lotufo; Kristianne Porta Santos, Fernandes; Ricardo Carneiro, Borra.

2011-10-01

269

Corporate Social Responsibility : WalMart, Maersk and the Cultural Bounds of Representation in Corporate Web Sites  

DEFF Research Database (Denmark)

Understanding Corporate Social Responsibility (CSR) as having explicit policies and implicit norms situated in cultural systems highlights the connections between institutional and cultural structures of nation states and business' commitment to CSR as reflected in the strategies used to communicate CSR to public audiences via the Internet.  To frame CSR from a situated perspective (Matten & Moon 2005) implies a shift in understanding relations between corporations and their stakeholders from a corporate-centered model to a cultural systems perspective.  This paper describes an approach to cultural systems in which can be used to frame our understanding of implicit norms with respect to CSR, and demonstrates how these norms result in different practices of communicating CSR in the WalMart and Maersk corporate websites.

Kampf, Constance

2007-01-01

270

Biography-Driven Strategies as the Great Equalizer: Universal Conditions that Promote K-12 Culturally Responsive Teaching  

Directory of Open Access Journals (Sweden)

Full Text Available The growing number of culturally and linguistically diverse (CLD students entering our public school system demands a new pedagogical framework for teaching and learning. With its emphasis on all four dimensions of the CLD student biography (sociocultural, linguistic, cognitive, academic, biography-driven culturally responsive teaching (Herrera, 2010 addresses the limited attention currently devoted to second language learning issues in the literature and research related to culturally responsive pedagogy. This study investigates the use of biography-driven instructional (BDI strategies by 58 general education teachers at the elementary and secondary levels with CLD students in their classrooms using the Biography-Driven Performance Rubric, which measures enactment of teaching standards and educational best practices. Findings indicate that the use of BDI strategies can facilitate the practical actualization of culturallyresponsive teaching. Findings also suggest that implementation of BDI strategies can help teachers overcome challenges that are unique to secondary settings as they accommodate the assets and needs of CLD learners.

Fanning, Cristina A.

2012-05-01

271

Sharpening the lens of culturally responsive science teaching: a call for liberatory education for oppressed student groups  

Science.gov (United States)

Wallace and Brand's framing of culturally responsive science teaching through the lens of critical race theory honors the role of social justice in science education. In this article, I extend the discussion through reflections on the particular learning needs of students from oppressed cultural groups, specifically African Americans. Understanding the political nature of education, I explore the importance of transforming science education so that it has the capacity to provide African American students with tools for their own liberation. I discuss Wallace and Brand's research findings in relation to the goal of liberatory education, and offer ideas for how science educators might push forward this agenda as they strive for culturally responsive teaching with oppressed student groups.

Codrington, Jamila

2014-01-01

272

Sharpening the lens of culturally responsive science teaching: a call for liberatory education for oppressed student groups  

Science.gov (United States)

Wallace and Brand's framing of culturally responsive science teaching through the lens of critical race theory honors the role of social justice in science education. In this article, I extend the discussion through reflections on the particular learning needs of students from oppressed cultural groups, specifically African Americans. Understanding the political nature of education, I explore the importance of transforming science education so that it has the capacity to provide African American students with tools for their own liberation. I discuss Wallace and Brand's research findings in relation to the goal of liberatory education, and offer ideas for how science educators might push forward this agenda as they strive for culturally responsive teaching with oppressed student groups.

Codrington, Jamila

2014-12-01

273

Creation of Culturally Responsive Classrooms: Teachers' Conceptualization of a New Rationale for Cultural Responsiveness and Management of Diversity in Hong Kong Secondary Schools  

Science.gov (United States)

Presently, there are a growing number of ethnic minority students in Hong Kong schools. This article examines teachers' views of the cross-cultural experience of ethnic minority students, their influence on the performance of these students, and how the diverse learning needs of these students are being addressed. Qualitative data were collected…

Hue, Ming-Tak; Kennedy, Kerry J.

2012-01-01

274

Effects of Science Interest and Environmental Responsibility on Science Aspiration and Achievement: Gender Differences and Cultural Supports  

Science.gov (United States)

The aim of the present study is twofold: (1) to investigate gender differences in the effects of science interest and environmental responsibility on science aspiration and achievement and (2) to explore the relations between cultural supports (macroeconomic and gender equality) and both boys' and girls' tendencies to integrate the aforementioned…

Chiu, Mei-Shiu

2010-01-01

275

Professional Development for Culturally Responsive and Relationship-Based Pedagogy. Black Studies and Critical Thinking. Volume 24  

Science.gov (United States)

The work presented here is a large-scale evaluation of a theory-driven school reform project in New Zealand, which focuses on improving the educational achievement of Maori students in public secondary schools. The project's conceptual underpinnings are based on Kaupapa Maori research, culturally responsive teaching, student voice, and…

Sleeter, Christine E., Ed.

2011-01-01

276

Theory and Practice of Positive Feminist Therapy: A Culturally Responsive Approach to Divorce Therapy with Chinese Women  

Science.gov (United States)

Positive Feminist Therapy (PFT) is a strength-based culturally responsive therapy model specifically designed for helping Chinese women facing marital conflicts and divorce, integrating Empowerment Feminist Therapy, systems theory, and positive psychology. To help clients become change agents, PFT uses clients' existing strengths to develop…

Tzou, Jean Yuh-Jin; Kim, Eunha; Waldheim, Kim

2012-01-01

277

Culturally Responsive Teaching in Yukon First Nation Settings: What Does It Look Like and What Is Its Influence?  

Science.gov (United States)

This study presents a pedagogical framework to inform culturally responsive teaching in a Yukon First Nations community. The paper describes the community-based processes used to develop the framework, and presents accounts from teachers who have used the framework to inform their teaching. Preliminary indications of the adjusted teaching…

Lewthwaite, Brian; Owen, Thomas; Doiron, Ashley; Renaud, Robert; McMillan, Barbara

2014-01-01

278

Assessing Autistic Traits in a Taiwan Preschool Population: Cross-Cultural Validation of the Social Responsiveness Scale (SRS)  

Science.gov (United States)

The cross-cultural validity of the Mandarin-adaptation of the social responsiveness scale (SRS) was examined in a sample of N = 307 participants in Taiwan, 140 typically developing and 167 with clinically-diagnosed developmental disorders. This scale is an autism assessment tool that provides a quantitative rather than categorical measure of…

Wang, Jessica; Lee, Li-Ching; Chen, Ying-Sheue; Hsu, Ju-Wei

2012-01-01

279

Effect of genotype, Culture medium and cold pretreatment on another culture of wheat (T. aestivum L.) mutant lines  

International Nuclear Information System (INIS)

This research was conducted in Tissue Culture Laboratory of the Nuclear Research Center for Agriculture and Medicine in the Atomic Energy Organization of Iran in 1996-1997. The objective was to investigate the effect of genotype, culture medium and cold pretreatment in calli production from anthers. Anthers of four mutant lines obtained from three cvs, (Omid, Tabassi and Roshan) were produced in the Nuclear Agriculture Center and two check cvs, (Omid and Tabassi) were cultured in two media PII and modified C17. Some of the spikes before plating were kept in dark at 4-5 deg C for one week. The result indicated that the genotype of donar plants had a significant effect on the calli and plants formation. Cold pre-treatment and medium type had no effect on the calli formation, but interaction between the two factors was very significant, and the best result was obtained when anthers were cultured in modified C17 medium without cold pre-treatment

280

Expression of Heat Shock and Other Stress Response Proteins in Ticks and Cultured Tick Cells in Response to Anaplasma spp. Infection and Heat Shock  

Science.gov (United States)

Ticks are ectoparasites of animals and humans that serve as vectors of Anaplasma and other pathogens that affect humans and animals worldwide. Ticks and the pathogens that they transmit have coevolved molecular interactions involving genetic traits of both the tick and the pathogen that mediate their development and survival. In this paper, the expression of heat shock proteins (HSPs) and other stress response proteins (SRPs) was characterized in ticks and cultured tick cells by proteomics and transcriptomics analyses in response to Anaplasma spp. infection and heat shock. The results of these studies demonstrated that the stress response was activated in ticks and cultured tick cells after Anaplasma spp. infection and heat shock. However, in the natural vector-pathogen relationship, HSPs and other SRPs were not strongly activated, which likely resulted from tick-pathogen coevolution. These results also demonstrated pathogen- and tick-specific differences in the expression of HSPs and other SRPs in ticks and cultured tick cells infected with Anaplasma spp. and suggested the existence of post-transcriptional mechanisms induced by Anaplasma spp. to control tick response to infection. These results illustrated the complexity of the stress response in ticks and suggested a function for the HSPs and other SRPs during Anaplasma spp. infection. PMID:22084679

Villar, Margarita; Ayllón, Nieves; Busby, Ann T.; Galindo, Ruth C.; Blouin, Edmour F.; Kocan, Katherine M.; Bonzón-Kulichenko, Elena; Zivkovic, Zorica; Almazán, Consuelo; Torina, Alessandra; Vázquez, Jesús; de la Fuente, José

2010-01-01

 
 
 
 
281

Characterization and response of newly developed high-grade glioma cultures to the tyrosine kinase inhibitors, erlotinib, gefitinib and imatinib.  

LENUS (Irish Health Repository)

High-grade gliomas (HGG), are the most common aggressive brain tumours in adults. Inhibitors targeting growth factor signalling pathways in glioma have shown a low clinical response rate. To accurately evaluate response to targeted therapies further in vitro studies are necessary. Growth factor pathway expression using epidermal growth factor receptor (EGFR), mutant EGFR (EGFRvIII), platelet derived growth factor receptor (PDGFR), C-Kit and C-Abl together with phosphatase and tensin homolog (PTEN) expression and downstream activation of AKT and phosphorylated ribosomal protein S6 (P70S6K) was analysed in 26 primary glioma cultures treated with the tyrosine kinase inhibitors (TKIs) erlotinib, gefitinib and imatinib. Response to TKIs was assessed using 50% inhibitory concentrations (IC(50)). Response for each culture was compared with the EGFR\\/PDGFR immunocytochemical pathway profile using hierarchical cluster analysis (HCA) and principal component analysis (PCA). Erlotinib response was not strongly associated with high expression of the growth factor pathway components. PTEN expression did not correlate with response to any of the three TKIs. Increased EGFR expression was associated with gefitinib response; increased PDGFR-? expression was associated with imatinib response. The results of this in vitro study suggest gefitinib and imatinib may have therapeutic potential in HGG tumours with a corresponding growth factor receptor expression profile.

Kinsella, Paula

2012-03-10

282

Pregnane x receptor modulates the inflammatory response in primary cultures of hepatocytes.  

Science.gov (United States)

Bacterial sepsis is characterized by a rapid increase in the expression of inflammatory mediators to initiate the acute phase response in liver. Inflammatory mediator release is counterbalanced by the coordinated expression of anti-inflammatory molecules such as interleukin 1 receptor antagonist (IL1-Ra) through time. This study determined whether activation of pregnane X receptor (PXR, NR1I2) alters the lipopolysaccharide (LPS)-inducible gene expression program in primary cultures of hepatocytes (PCHs). Preactivation of PXR for 24 hours in PCHs isolated from wild-type mice suppressed the subsequent LPS-inducible expression of the key inflammatory mediators interleukin 1? (IL-1?), interleukin 6 (IL-6), and tumor necrosis factor ? (TNF?) but not in PCHs isolated from Pxr-null (PXR-knockout [KO]) mice. Basal expression of key inflammatory cytokines was elevated in PCHs from PXR-KO mice. Stimulation of PCHs from PXR-KO mice with LPS alone produced enhanced levels of IL-1? when compared with wild-type mice. Experiments performed using PCHs from both humanized-PXR transgenic mice as well as human donors indicate that prolonged activation of PXR produces an increased secretion of IL1-Ra from cells through time. Our data reveal a working model that describes a pivotal role for PXR in both inhibiting as well as in resolving the inflammatory response in hepatocytes. Understanding the molecular details of how PXR is converted from a positive regulator of drug-metabolizing enzymes into a transcriptional suppressor of inflammation in liver will provide new pharmacologic strategies for modulating inflammatory-related diseases in the liver and intestine. PMID:25527709

Sun, Mengxi; Cui, Wenqi; Woody, Sarah K; Staudinger, Jeff L

2015-03-01

283

Growth response and survival of Heterobranchus longifilis cultured at different water levels in outdoor concrete tanks  

Directory of Open Access Journals (Sweden)

Full Text Available Thirteen-day-old hatchery-raised fry obtained from hormonally-induced spawns of mature African catfish H. longifilis brood stock were introduced to three different water levels (0.35, 0.50 and 0.65m in four replicates in 12 units of 2x2x1m3 outdoor concrete tanks. The fry were similarly stocked initially at 50 fry m-2 and later thinned down to 5 fish m-2 and cultured for 6 months. Fish were fed twice daily with commercial pellet feeds (Coppens™ while adjusting the feeding rate from 10 to 4% body weight and pellet size from 0.2 to 4.5 mm. The effects of pond water levels were evaluated in growth responses and survival. Water quality variables were similar (p > 0.05 in all compartments. Temperature, dissolved oxygen and pH were at the optimum level for fish. The results reveal significant (P H. longifilis from fry to sub-adult and from the grow-out/fattening of sub-adult to adult, respectively, in outdoor concrete tanks.

Anthony A. Nlewadim

2011-07-01

284

Cross-cultural sex differences in situational triggers of aggressive responses.  

Science.gov (United States)

This paper examines male and female individual differences in situational triggers of aggressive responses (STAR) in three countries as well as cross-cultural sex differences in trait aggression (aggression questionnaire, AQ). Convenience sampling was employed (university students) for the descriptive correlational study (Poland N = 300, 63% female, mean age 21.86, SD = 2.12; UK N = 196, 60% female, mean age 20.48, SD = 3.79; Greece N = 299, 57% female, mean age 20.71, SD = 4.42). The results showed that the STAR scale is an equivalent construct across all three countries. Overall, females were more sensitive to both provocation (SP) and frustration (SF) than males. When controlling for trait aggression, Polish and Greek females scored similarly in SP and higher than UK females. No sex differences in SP or SF were found in the UK sample. Additionally, Polish participants scored the highest in SP. Furthermore, when trait aggression was removed, the Greek participants were most sensitive to frustration, whereas Polish and English participants' SF did not differ. We discuss the results with regard to intercultural differences between investigated countries. PMID:25178957

Zajenkowska, Anna; Mylonas, Kostas; Lawrence, Claire; Konopka, Karolina; Rajchert, Joanna

2014-10-01

285

Characterization of a Collection of Brassica carinata Genotypes for in vitro Culture Response and Mode of Shoot Regeneration  

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Full Text Available Brassica carinata, a natural alloploid formed between B. oleracea and B. nigra, is a potential oil crop for the Mediterranean area in which genetic transformation could help to breeding. In vitro culture and shoot regeneration are key factors in developing an efficient transformation method in the genus Brassica. However, the studies for in vitro culture and shoot regeneration in B. carinata are limited to only a few genotypes. The aim of this study was to evaluate the in vitro culture response and shoot regeneration in a collection of B. carinata accessions to identify promising genotypes with high shoot regeneration for genetic transformation experiments. Cotyledonary explants from 51 genotypes were cultured in vitro and callus formation and swelling as well as the mode of shoot regeneration evaluated. A highly positive response to in vitro culture, i.e. callus formation or swelling, was observed in all the genotypes tested. Tissue blackening occurred only in eleven genotypes. Parameters like callus formation and swelling, and number of shoots per explant were highly variable among genotypes. Fourteen genotypes regenerated only via callus formation, whereas only one regenerated only via swelling. Most genotypes showed a higher percentage of callus formation than swelling. The average number of shoots regenerating per explant among genotypes was the most variable factor measured. Six genotypes regenerated more than 6 shoots per explant via callus phase. These genotypes have been identified as having a high regeneration potential and can be used in genetic transformation via Agrobacterium.

Antonio Martín

2011-03-01

286

La mujer responsable de la salud de la familia: Constatando la universalidad cultural del cuidado Women in charge of family health-verifying cultural universality of care  

Directory of Open Access Journals (Sweden)

Full Text Available Introducción: La reducida familiarización de los prestadores de cuidados a la salud sobre el proceso socio-cultural que orienta el comportamiento de los individuos en el cuidado de su salud, motivó este estudio. Objetivo: Identificar factores culturales presentes en las acciones de la mujer al cuidar al familiar con afecciones físicas y o mentales. Método: Se trata de un estudio transcultural formado por dos investigaciones que adoptaron la Antropología cultural y el método etnográfico. Uno de los estudios fue realizado con 6 mujeres que vivían en una comunidad urbano marginal de São Paulo-Brasil y otro con mujeres de 6 familias de dos provincias de Lambayeque-Perú. Resultados: Ambas investigaciones mostraron que, frente a una enfermedad física o mental del familiar, la mujer se responsabiliza de su tratamiento empleando prácticas domésticas, místicas o buscando atención médica rápida y eficaz. Mostraron que es la mujer la que percibe alteraciones en el estado de salud del familiar. Conclusión: Los diferentes contextos culturales presentan semejanzas que los aproximan y apuntan la necesidad de atención, de los profesionales de salud, al cuidado centrado en la mujer, considerando su cultura.Introduction: Health Care Providers' little familiarization with the socio-cultural process that directs the behavior of individuals concerning their health care brought about this study. Objective: To identify the cultural factors present in the woman's action when taking care of a family member with either physical or mental disability. Method: This is a transcultural study made up of two researches that adopted the Cultural Anthropology and ethnographic study as well. One of the studies was carried out with six inhabitants in a slum in the city of Sao Paulo, Brazil and the other with women from six families of two provinces in Lambayeque, Peru. Results: Both researches showed that, in the face of either a physical or mental disability of a family member, the woman takes responsibility for their treatment adopting domestic, mystic practices and/or searches for prompt and effective medical service. The researches also showed that it is the woman who notices alterations in their health pattern. Conclusion: The different cultural contexts have similarities that approximate them and both indicate the need for health care providers' attention towards a kind of care focused on the women considering their culture.

María Concepción Pezo Silva

2004-11-01

287

How cultural capital, habitus and class influence the responses of older adults to the field of contemporary visual art?  

Science.gov (United States)

This article explores the responses of 38 older people to contemporary visual art through the results of a 28-month study entitled, Contemporary Visual Art and Identity Construction: Wellbeing amongst Older People. A framework for the analysis is provided by previous work on the consumption of art and by Bourdieu's constructs of cultural capital, habitus and field. Five groups of older people, with a range of different backgrounds, were taken to galleries and their responses were recorded, transcribed and analysed. It is concluded that participants’ responses are influenced by their cultural capital, habitus and class—which, in turn, are affected by their life course experiences. Those who could not recognise the field (e.g., did not view contemporary art as “art”) created their own meanings that they associated with the artworks. Evidence indicates that group dynamics and class mobility are likewise important. Participants also used the experience to respond to real or anticipated age-associated deficits. PMID:24748712

Newman, Andrew; Goulding, Anna; Whitehead, Christopher

2013-01-01

288

Characterization and response of newly developed high-grade glioma cultures to the tyrosine kinase inhibitors, erlotinib, gefitinib and imatinib  

Energy Technology Data Exchange (ETDEWEB)

High-grade gliomas (HGG), are the most common aggressive brain tumours in adults. Inhibitors targeting growth factor signalling pathways in glioma have shown a low clinical response rate. To accurately evaluate response to targeted therapies further in vitro studies are necessary. Growth factor pathway expression using epidermal growth factor receptor (EGFR), mutant EGFR (EGFRvIII), platelet derived growth factor receptor (PDGFR), C-Kit and C-Abl together with phosphatase and tensin homolog (PTEN) expression and downstream activation of AKT and phosphorylated ribosomal protein S6 (P70S6K) was analysed in 26 primary glioma cultures treated with the tyrosine kinase inhibitors (TKIs) erlotinib, gefitinib and imatinib. Response to TKIs was assessed using 50% inhibitory concentrations (IC{sub 50}). Response for each culture was compared with the EGFR/PDGFR immunocytochemical pathway profile using hierarchical cluster analysis (HCA) and principal component analysis (PCA). Erlotinib response was not strongly associated with high expression of the growth factor pathway components. PTEN expression did not correlate with response to any of the three TKIs. Increased EGFR expression was associated with gefitinib response; increased PDGFR-{alpha} expression was associated with imatinib response. The results of this in vitro study suggest gefitinib and imatinib may have therapeutic potential in HGG tumours with a corresponding growth factor receptor expression profile. -- Highlights: Black-Right-Pointing-Pointer Non-responders had low EGFR expression, high PDGFR-{beta}, and a low proliferation rate. Black-Right-Pointing-Pointer PTEN is not indicative of response to a TKI. Black-Right-Pointing-Pointer Erlotinib response was not associated with expression of the proteins examined. Black-Right-Pointing-Pointer Imatinib-response correlated with expression of PDGFR-{alpha}. Black-Right-Pointing-Pointer Gefitinib response correlated with increased expression of EGFR.

Kinsella, Paula, E-mail: paula.kinsella@dcu.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); Howley, Rachel, E-mail: rhowley@rcsi.ie [Department of Neuropathology, Beaumont Hospital, Dublin 9 (Ireland); Doolan, Padraig, E-mail: padraig.doolan@dcu.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); Clarke, Colin, E-mail: colin.clarke@dcu.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); Madden, Stephen F., E-mail: maddens@dcu.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); Clynes, Martin, E-mail: Martin.Clynes@dcu.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); Farrell, Michael, E-mail: michaelfarrell@beaumont.ie [Department of Neuropathology, Beaumont Hospital, Dublin 9 (Ireland); Amberger-Murphy, Verena, E-mail: Verena.Murphy@icorg.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); All Ireland Co-operative, Oncology Research Group, 60 Fitzwilliam Square, Dublin 2 (Ireland)

2012-03-10

289

Characterization and response of newly developed high-grade glioma cultures to the tyrosine kinase inhibitors, erlotinib, gefitinib and imatinib  

International Nuclear Information System (INIS)

High-grade gliomas (HGG), are the most common aggressive brain tumours in adults. Inhibitors targeting growth factor signalling pathways in glioma have shown a low clinical response rate. To accurately evaluate response to targeted therapies further in vitro studies are necessary. Growth factor pathway expression using epidermal growth factor receptor (EGFR), mutant EGFR (EGFRvIII), platelet derived growth factor receptor (PDGFR), C-Kit and C-Abl together with phosphatase and tensin homolog (PTEN) expression and downstream activation of AKT and phosphorylated ribosomal protein S6 (P70S6K) was analysed in 26 primary glioma cultures treated with the tyrosine kinase inhibitors (TKIs) erlotinib, gefitinib and imatinib. Response to TKIs was assessed using 50% inhibitory concentrations (IC50). Response for each culture was compared with the EGFR/PDGFR immunocytochemical pathway profile using hierarchical cluster analysis (HCA) and principal component analysis (PCA). Erlotinib response was not strongly associated with high expression of the growth factor pathway components. PTEN expression did not correlate with response to any of the three TKIs. Increased EGFR expression was associated with gefitinib response; increased PDGFR-? expression was associated with imatinib response. The results of this in vitro study suggest gefitinib and imatinib may have therapeutic potential in HGG tumours with a corresponding growth factor receptor expression profile. -- Highlights: ? Non-responders had low EGFR expression, high PDGFR-?, and a low proliferation rate. ? PTEN is not indicative of response to a TKI. ? Erlotinib response was not associated with expression of the proteins examined. ? Imatinib-response correlated with expression of PDGFR-?. ? Gefitinib response correlated with increased expression of EGFR.

290

Número de anteras por flor, grãos de pólen por antera e capacidade germinativa do pólen de diferentes cultivares de macieiras / Number of anthers per flower, pollen grains per anther and pollen germination capacity of different cultivars of apple trees  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O objetivo deste trabalho foi avaliar o número de anteras por flor, grãos de pólen por antera e capacidade germinativa do pólen de diferentes cultivares de macieiras. O trabalho foi executado no Laboratório de Fisiologia do Desenvolvimento e Genética Vegetal da Universidade Federal de Santa Catarina [...] , e as coletas a campo foram realizadas na Epagri/Estação Experimental de Caçador-SC, em outubro de 2005. Foram utilizadas as seguintes cultivares comerciais de macieira desenvolvidas no Brasil: Primícia, Princesa, Fred Hough, Catarina, Baronesa, Lisgala, Suprema, Condessa, Daiane, Duquesa, Imperatriz e Joaquina. As cultivares de macieira Condessa, Princesa, Eva, Duquesa, Imperatriz, Gala, Fred Hough, Daiane, Baronesa e Suprema produzem pólen em quantidade suficiente e com boa capacidade germinativa. A cv. Condessa, embora apresente alta capacidade germinativa de pólen, produz menos anteras e grãos de pólen por antera que as demais. A cv. Princesa é a que apresenta o melhor perfil como polinizadora, por conjugar número de anteras/flor, número de grãos de pólen/antera e capacidade germinativa do pólen mais satisfatórios. Abstract in english The objective of this study was to evaluate the number of anthers per flower, the number of pollen grains per anther and the pollen germination capacity of different cultivars of apple trees. The study was performed at the Physiology and Plant Genetics Laboratory of Federal University of Santa Catar [...] ina. The field collecting were performed at Epagri / Caçador Experimental Station, in Santa Catarina State during October, 2005. It was used the following apple cultivars developed in Brazil: Primícia, Princesa, Fred Hough, Catarina, Baronesa, Lisgala, Suprema, Condessa, Daiane, Duquesa, Imperatriz and Joaquina. It was concluded that the apple cultivars Condessa, Princesa, Eva, Duquesa, Imperatriz, Gala, Fred Hough, Daiane, Baronesa and Suprema produce pollen grains of satisfactory quantity and of good germination capacity. The cv. Condessa, although having high pollen germination capacity, produces less anthers and less pollen grains per anther than the others. Princesa is the cultivar of best pattern as pollinizer, once it combines number of anthers/flower, number of pollen grains/anther and pollen germination capacity in a better satisfactory level.

Celso Lopes de, Albuquerque Junior; Frederico, Denardi; Adriana Cibele de Mesquita, Dantas; Rubens Onofre, Nodari.

1255-12-01

291

Efficient transformation of Kalanchoe blossfeldiana and production of male-sterile plants by engineered anther ablation.  

Science.gov (United States)

Engineered male sterility in ornamental plants has many applications such as facilitate hybrid seed production, eliminate pollen allergens, reduce the need for deadheading to extend the flowering period, redirect resources from seeds to vegetative growth, increase flower longevity and prevent gene flow between genetically modified and related native plants. We have developed a reliable and efficient Agrobacterium-mediated protocol for the genetic transformation of different Kalanchoe blossfeldiana commercial cultivars. Transformation efficiency for cv. 'Hillary' was 55.3% whereas that of cv. 'Tenorio' reached 75.8%. Selection was carried out with the nptII gene and increasing the kanamycin concentration from 25 to 100 mg l(-1) allowed to reduced escapes from 50 to 60% to virtually 0%. This method was used to produce male-sterile plants through engineered anther ablation. In our approach, we tested a male sterility chimaeric gene construct (PsEND1::barnase) to evaluate its effectiveness and effect on phenotype. No significant differences were found in the growth patterns between the transgenic lines and the wild-type plants. No viable pollen grains were observed in the ablated anthers of any of the lines carrying the PsEND1::barnase construct, indicating that the male sterility was complete. In addition, seed set was completely abolished in all the transgenic plants obtained. Our engineered male-sterile approach could be used, alone or in combination with a female-sterility system, to reduce the invasive potential of new ornamentals, which has become an important environmental problem in many countries. PMID:19921199

García-Sogo, Begoña; Pineda, Benito; Castelblanque, Lourdes; Antón, Teresa; Medina, Mónica; Roque, Edelín; Torresi, Claudia; Beltrán, José Pío; Moreno, Vicente; Cañas, Luis Antonio

2010-01-01

292

Temperature stress differentially modulates transcription in meiotic anthers of heat-tolerant and heat-sensitive tomato plants  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Fluctuations in temperature occur naturally during plant growth and reproduction. However, in the hot summers this variation may become stressful and damaging for the molecular mechanisms involved in proper cell growth, impairing thus plant development and particularly fruit-set in many crop plants. Tolerance to such a stress can be achieved by constitutive gene expression or by rapid changes in gene expression, which ultimately leads to protection against thermal damage. We have used cDNA-AFLP and microarray analyses to compare the early response of the tomato meiotic anther transcriptome to moderate heat stress conditions (32°C in a heat-tolerant and a heat-sensitive tomato genotype. In the light of the expected global temperature increases, elucidating such protective mechanisms and identifying candidate tolerance genes can be used to improve breeding strategies for crop tolerance to heat stress. Results The cDNA-AFLP analysis shows that 30 h of moderate heat stress (MHS alter the expression of approximately 1% of the studied transcript-derived fragments in a heat-sensitive genotype. The major effect is gene down-regulation after the first 2 h of stress. The microarray analysis subsequently applied to elucidate early responses of a heat-tolerant and a heat-sensitive tomato genotype, also shows about 1% of the genes having significant changes in expression after the 2 h of stress. The tolerant genotype not only reacts with moderate transcriptomic changes but also exhibits constitutively higher expression levels of genes involved in protection and thermotolerance. Conclusion In contrast to the heat-sensitive genotype, the heat-tolerant genotype exhibits moderate transcriptional changes under moderate heat stress. Moreover, the heat-tolerant genotype also shows a different constitutive gene expression profile compared to the heat-sensitive genotype, indicating genetic differences in adaptation to increased temperatures. In the heat-tolerant genotype, the majority of changes in gene expression is represented by up-regulation, while in the heat-sensitive genotype there is a general trend to down-regulate gene expression upon MHS. The putative functions associated with the genes identified by cDNA-AFLP or microarray indicate the involvement of heat shock, metabolism, antioxidant and development pathways. Based on the observed differences in response to MHS and on literature sources, we identified a number of candidate transcripts involved in heat-tolerance.

Pezzotti Mario

2011-07-01

293

The extent to which Latina/o preservice teachers demonstrate culturally responsive teaching practices during science and mathematics instruction  

Science.gov (United States)

Complex social, racial, economic, and political issues involved in the practice of teaching today require beginning teachers to be informed, skilled, and culturally responsive when entering the classroom. Teacher educators must educate future teachers in ways that will help them teach all children regardless of language, cultural background, or prior knowledge. The purpose of this study was to explore the extent to which culturally and linguistically diverse (CLD) novice teachers described and demonstrated culturally responsive teaching strategies using their students' cultural and academic profiles to inform practice in science and mathematics instruction. This qualitative exploratory case study considered the culturally responsive teaching practices of 12, non-traditional, Latina/o students as they progressed through a distance-based collaborative teacher education program. Qualitative techniques used throughout this exploratory case study investigated cultural responsiveness of these student teachers as they demonstrated their abilities to: a) integrate content and facilitate knowledge construction; b) illustrate social justice and prejudice reduction; and c) develop students academically. In conclusion, student teachers participating in this study demonstrated their ability to integrate content by: (1) including content from other cultures, (2) building positive teacher-student relationships, and (3) holding high expectations for all students. They also demonstrated their ability to facilitate knowledge construction by building on what students knew. Since there is not sufficient data to support the student teachers' abilities to assist students in learning to be critical, independent thinkers who are open to other ways of knowing, no conclusions regarding this subcategory could be drawn. Student teachers in this study illustrated prejudice reduction by: (1) using native language support to assist students in learning and understanding science and math content, (2) fostering positive student-student interactions, and (3) creating a safe learning environment. Results also indicated that these student teachers demonstrated their ability to develop students academically by creating opportunities for learning in the classroom through their knowledge of students and by the use of research-based instructional strategies. However, based on the data collected as part of this study, the student teachers' abilities to illustrate or model social justice during science and math instruction were not demonstrated.

Hernandez, Cecilia M.

2011-12-01

294

The EXCESS MICROSPOROCYTES1 gene encodes a putative leucine-rich repeat receptor protein kinase that controls somatic and reproductive cell fates in the Arabidopsis anther  

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Cell differentiation is essential for the development of multicellular organisms. In flowering plants, the haploid male gametophytes (pollen grains) are generated in the anther from reproductive cells called microsporocytes. Several types of somatic cells ensure successful pollen development, and thus reproduction. However, it is not clear what genes regulate the differentiation of these diverse, highly specialized cells in the anther. We report here the isolation and characterization of a no...

Zhao, Da-zhong; Wang, Guan-fang; Speal, Brooke; Ma, Hong

2002-01-01

295

Effects of Field Plot Size on Variation in White Flower Anther Injury by Tarnished Plant Bug for Host Plant Resistance Evaluations in Arkansas Cotton  

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Field trials conducted in 2008 and 2009 investigated whether plot size affects incidence of white flower anther injury by tarnished plant bug (Lygus lineolaris (Palisot de Beauvois)) in host plant resistance (HPR) evaluations. The three cotton lines evaluated in the trial included a susceptible frego bract line (RBCDHGPIQH-197) and 2 standards, SureGrow (SG) 105 and Deltapine (DP) 393. Samplers monitored white flower anther injury between single row mini-plots embedded within multiple row ma...

Jeffrey Willers; Tina Gray Teague; George Milliken; Fred Bourland

2014-01-01

296

The Effect of the Confidence Notion in the Chinese Culture Through the Dictums  

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The Chinese dictum conveys his culture. The present paper aims to make a survey on the confidence notion in the Chinese culture. This notion is bound to the anthers virtues such as human sense, ritual spirit, just sense, wisdom. Theses notions constitute five guiding principles. The confidence notion is worth considering, because it can ensure the human contact. We attach attention to this notion in order to construct a harmonious society.
Key words: d...

Chen, Sui-xiang

2010-01-01

297

Morphological development of anthers induced by the dimorphic smut fungus Microbotryum violaceum in female flowers of the dioecious plant Silene latifolia.  

Science.gov (United States)

When inoculated with the dimorphic smut fungus Microbotryum violaceum (Pers.) G. Deml and Oberwinkler, the female flower of the dioecious plant Silene latifolia (Miller) E.H.L. Krause develops anther-like structures filled with spores instead of pollen grains. Using natural scanning electron microscopy, Nomarski interference microscopy, and fluorescence microscopy, we investigated the morphological modifications of the host plant resulting from this parasitism and the localization of smut hyphae in the flower bud. Flowers of infected plants lasted significantly longer than those of healthy plants, probably because the infection strengthened floral organs, such as the flower base and the anther filaments. Smut hyphae were observed throughout all organs of the young flower buds of infected plants, including sepals, petals, stamens, and pistil primordia. In healthy female flowers, anthers initiated sporogenous cell formation, but lacked parietal cell layers. By contrast, the parietal cell layers of infected female flowers differentiated into tapetal tissue, middle cell layers, and endothecial layers, as in the anthers of healthy male flowers. Smut spore formation in the infected anther was initiated in intercellular regions between the sporogenous cells, resulting in degeneration of premature sporogenous cells, tapetal tissue, and middle cell layers. The development of the endothecial layers and epidermis in the infected anther were morphologically normal. PMID:14551772

Uchida, Wakana; Matsunaga, Sachihiro; Sugiyama, Ryuji; Kazama, Yusuke; Kawano, Shigeyuki

2003-12-01

298

Keeping up the Conversation on Culture: A Response to Robert Courchene and Others  

Science.gov (United States)

Robert Courchene's 1996 article entitled "Teaching Canadian Culture: Teacher Preparation" sparked a conversation in the pages of the "TESL Canada Journal" that continues today. From advocating the teaching of significant historical events and icons to encouraging second-language learners to embrace cultural ambiguity, there is a wide spectrum of…

Walsh-Marr, Jennifer

2011-01-01

299

Development and Preliminary Analysis of a Rubric for Culturally Responsive Research  

Science.gov (United States)

Researchers and practitioners have struggled to promote optimal academic, behavioral, and postschool outcomes for historically marginalized youth from culturally and linguistically diverse backgrounds. While there is a growing body of evidence-based interventions in special education, the extent to which these interventions are culturally

Trainor, Audrey A.; Bal, Aydin

2014-01-01

300

Thermotolerance and the heat shock response in normal human keratinocytes in culture  

International Nuclear Information System (INIS)

Protective responses of normal human epidermal keratinocytes in culture, after exposure to elevated temperatures (heat shock), were examined. Cell viability, measured 24-48 h after a 20-min heat challenge at temperatures between 37 degrees C and 54 degrees C, declined sharply within a narrow 2 degrees-3 degrees C range. However, conditioning with a mild thermal pretreatment (40 degrees C or 42 degrees C for 1 h) protected the keratinocytes against a subsequent heat challenge. This induced thermotolerance was apparent when cells were challenged at 1, 3, and 6 h after the thermal pre-treatment, but disappeared by 24 h. Heating conditions that induce thermotolerance also stimulated the synthesis of heat-shock proteins (hsp) in these cells. Inductions of prominent 35S-methionine labeled bands at 70, 78, and 90 kDa were observed. However, the increases in synthesis of these heat-shock proteins did not correlate well with thermotolerance, because large increases were also observed at certain elevated temperatures that did not produce improved survival. Keratins observed in these cells (50 and 58 kDa classes) were not induced by heat shock. The development of thermotolerance, and the induction of hsp, were both completely blocked by 3'-deoxyadenosine (cordycepin), an inhibitor of newly synthesized messenger RNA, but not by adenosine, the normal analog. While heat-inducible mRNA apparently mediate some function important for the development of thermotolerance, the nature of topment of thermotolerance, the nature of that role remains speculative. Overall, our findings establish the existence of a functional thermal protective mechanism in human keratinocytes that appears to require the synthesis of new mRNA

 
 
 
 
301

A Sensitive Sensor Cell Line for the Detection of Oxidative Stress Responses in Cultured Human Keratinocytes  

Directory of Open Access Journals (Sweden)

Full Text Available In the progress of allergic and irritant contact dermatitis, chemicals that cause the generation of reactive oxygen species trigger a heat shock response in keratinocytes. In this study, an optical sensor cell line based on cultured human keratinocytes (HaCaT cells expressing green fluorescent protein (GFP under the control of the stress-inducible HSP70B’ promoter were constructed. Exposure of HaCaT sensor cells to 25 µM cadmium, a model substance for oxidative stress induction, provoked a 1.7-fold increase in total glutathione and a ~300-fold induction of transcript level of the gene coding for heat shock protein HSP70B’. An extract of Arnica montana flowers resulted in a strong induction of the HSP70B’ gene and a pronounced decrease of total glutathione in keratinocytes. The HSP70B’ promoter-based sensor cells conveniently detected cadmium-induced stress using GFP fluorescence as read-out with a limit of detection of 6 µM cadmium. In addition the sensor cells responded to exposure of cells to A. montana extract with induction of GFP fluorescence. Thus, the HaCaT sensor cells provide a means for the automated detection of the compromised redox status of keratinocytes as an early indicator of the development of human skin disorders and could be applied for the prediction of skin irritation in more complex in vitro 3D human skin models and in the development of micro-total analysis systems (µTAS that may be utilized in dermatology, toxicology, pharmacology and drug screenings.

Ute Hofmann

2014-06-01

302

A sensitive sensor cell line for the detection of oxidative stress responses in cultured human keratinocytes.  

Science.gov (United States)

In the progress of allergic and irritant contact dermatitis, chemicals that cause the generation of reactive oxygen species trigger a heat shock response in keratinocytes. In this study, an optical sensor cell line based on cultured human keratinocytes (HaCaT cells) expressing green fluorescent protein (GFP) under the control of the stress-inducible HSP70B' promoter were constructed. Exposure of HaCaT sensor cells to 25 µM cadmium, a model substance for oxidative stress induction, provoked a 1.7-fold increase in total glutathione and a ~300-fold induction of transcript level of the gene coding for heat shock protein HSP70B'. An extract of Arnica montana flowers resulted in a strong induction of the HSP70B' gene and a pronounced decrease of total glutathione in keratinocytes. The HSP70B' promoter-based sensor cells conveniently detected cadmium-induced stress using GFP fluorescence as read-out with a limit of detection of 6 µM cadmium. In addition the sensor cells responded to exposure of cells to A. montana extract with induction of GFP fluorescence. Thus, the HaCaT sensor cells provide a means for the automated detection of the compromised redox status of keratinocytes as an early indicator of the development of human skin disorders and could be applied for the prediction of skin irritation in more complex in vitro 3D human skin models and in the development of micro-total analysis systems (µTAS) that may be utilized in dermatology, toxicology, pharmacology and drug screenings. PMID:24967604

Hofmann, Ute; Priem, Melanie; Bartzsch, Christine; Winckler, Thomas; Feller, Karl-Heinz

2014-01-01

303

Dose-response relationship of cadmium or radiation-induced embryotoxicity in mouse whole embryo culture  

International Nuclear Information System (INIS)

Mouse embryos of B6C3F1 strain were exposed in vitro to 1.2 to 2.2 ?M cadmium chloride (Cd) or to 100 to 320 R x-rays, and the effects of the exposure on development were examined after 39 h of culture. Development of embryos was assessed from lethality, formation of the neural tube defect, diameter and protein of yolk sac, crown-rump and head lengths, embryonic protein, and number of somites. Incidence of the neural tube defect increased from 3.4 to 100% by 1.2 to 2.0 ?M Cd, while embryo deaths increased from 13.8 to 93.3% by 2.0 to 2.2 ?M Cd. Embryonic protein was significantly reduced at the teratogenic range, but the number of somites was only affected by 1.6 to 2.0 ?M Cd. X-irradiation at 100 to 320 R induced the neural tube defect in 2.9 to 72.7% of the embryos. An embryolethal effect was observed only at the 320 R dose. Crown-rump and head lengths and embryonic protein were significantly affected at the teratogenic range, but the diameter and protein of yolk sac and number of somites were hardly affected. Cadmium- or radiation-induced response data of both teratogenicity and endpoints indicating inhibition of embryonic development were acceptably fitted to a linear log-probit regression. These regressions suggest that as an estimation of interference in development of embryos, embryonic protein and head length are sensitive endpoints while the number of somites is an insensitive criterion. (author)

304

Endothelial cells co-stimulate peripheral blood mononuclear cell responses to monoclonal antibody TGN1412 in culture.  

Science.gov (United States)

The failure of preclinical testing to predict the severity of the cytokine storm experienced by the recipients of the superagonistic anti-CD28 monoclonal antibody (mAb) TGN1412 during its Phase 1 clinical trial prompted the development of new in vitro experimental approaches for mimicking in vivo cytokine release and lymphoproliferation. Peripheral blood mononuclear cells (PBMC) presented to TGN1412 immobilised on plastic has previously been shown to stimulate a pro-inflammatory cytokine response. The aim of the present study was to investigate a 'co-culture' model for the detection of TGN1412-like immunomodulatory activity in which TGN1412 was presented to PBMC in the presence of monolayers of endothelium-derived cells and other cell types, followed by measurement of cytokine levels in the culture supernatants and proliferation of PBMC. Culturing PBMC with TGN1412 over primary human umbilical vein endothelial cells (HUVEC) and HUVEC-derived cell lines retaining classic endothelial markers, but not cell lines of non-endothelial origin, mediated the specific release of IL-6, IL-8 and TNF?, and proliferation of PBMC. Low levels of IL-2 and IFN? were also detected in supernatants with most donors of PBMC. An anti-CD28 mAb agonist, i.e., not a superagonist like TGN1412, did not stimulate cytokine release or proliferation of PBMC in co-cultures. In conclusion, co-culture experiments for TGN1412-specific cytokine release required cells of endothelial origin. However, the profile of released cytokines in co-cultures did not mirror that in the clinical trial participants or the responses from PBMC exposed to TGN1412 immobilised on plastic, suggesting that TGN1412 stimulation of PBMC can occur through more than one mechanism. PMID:21493088

Findlay, Lucy; Sharp, Giles; Fox, Bernard; Ball, Christina; Robinson, C Jane; Bird, Christopher; Stebbings, Richard; Eastwood, David; Wadhwa, Meenu; Poole, Stephen; Thorpe, Robin; Thorpe, Susan J

2011-07-01

305

Culturable bacteria in Himalayan glacial ice in response to atmospheric circulation  

Directory of Open Access Journals (Sweden)

Full Text Available Only recently has specific attention been given to culturable bacteria in Tibetan glaciers, but their relation to atmospheric circulation is less understood yet. Here we present the results of culturable bacteria preserved in an ice core drilled from the East Rongbuk (ER glacier, Himalayas. The average concentrations of culturable bacteria are 5.0, 0.8, 0.1 and 0.7 CFU mL?1 for the glacier ice deposited during the premonsoon, monsoon, postmonsoon and winter seasons, respectively. The high concentration of culturable bacteria in ER glacier deposited during the premonsoon season is attributed to the transportation of continental dust stirred up by the frequent dust storms during spring. This is also confirmed by the spatial distribution of culturable bacteria in Tibetan glaciers. Continental dust originated from the Northwest China accounts for the high abundance of culturable bacteria in the northern Tibetan Plateau, while monsoon moisture exerts great influence on culturable bacteria with low abundance in the southern plateau. The numbers of representatives with different ARDRA patterns from RFLP analysis are 10, 15, 1 and 2 for the glacial ice deposited during the premonsoon, monsoon, postmonsoon and winter seasons, respectively, suggesting that culturable bacteria deposited in ER glacier during monsoon season are more diverse than that deposited during the other seasons, possibly due to their derivation from both marine air masses and local or regional continental sources, while culturable bacteria deposited during the other seasons are from only one possible origin that is transported by westerlies. Our results show the first report of seasonal variations of abundance and species diversity of culturable bacteria recovered from glacial ice in the Himalayas, and we suggest that microorganisms in Himalayan ice might provide a potential new proxy for the reconstruction of atmospheric circulation.

S. Zhang

2007-01-01

306

Upregulation of the AT-hook DNA binding gene BoMF2 in OguCMS anthers of Brassica oleracea suggests that it encodes a transcriptional regulatory factor for anther development.  

Science.gov (United States)

Ogura cytoplasmic male sterility (OguCMS) is the most important CMS system used for F1 hybrid cabbage production worldwide. The anther abortion and defective pollen development exhibited in OguCMS are coordinately regulated by the mitochondrial male sterile gene orf138 and many nuclear transcriptional regulatory factors. AT-hook DNA binding proteins regulate cell-specific gene expression. In this study, we cloned the gene encoding the AT-hook DNA binding protein BoMF2 using the cDNA-AFLP TDF sequence, which was upregulated in OguCMS cabbage flower buds, as a querying probe. BoMF2 contains a 783-nt continuous complete open reading frame encoding a 260 amino-acid polypeptide. In vivo transient expression assays using GFP fusions showed that BoMF2 protein was located in the nucleus. BoMF2 was preferentially expressed in cabbage stamens, with a short expression window at anther development stage 7-8. However, in OguCMS flowers, BoMF2 expression continued into the mature pollen stage and was concomitant with the continued proliferation of tapetum cells exhibited in this mutant. Arabidopsis plants overexpressing BoMF2 showed significantly shorter siliques than the wild type, as well as decrease of pollen viability. These results suggest that BoMF2, a transcriptional regulatory factor, might regulate tapetum proliferation during anther development. PMID:24443226

Kang, Jungen; Guo, Yingying; Chen, Yujuan; Li, Hailong; Zhang, Lei; Liu, Haixia

2014-01-01

307

Conserved host response to highly pathogenic avian influenza virus infection in human cell culture, mouse and macaque model systems  

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Abstract Background Understanding host response to influenza virus infection will facilitate development of better diagnoses and therapeutic interventions. Several different experimental models have been used as a proxy for human infection, including cell cultures derived from human cells, mice, and non-human primates. Each of these systems has been studied extensively in isolation, but little effort has been directed toward systematically characterizing the conservation of h...

McDermott Jason E; Shankaran Harish; Eisfeld Amie J; Belisle Sarah E; Neuman Gabriele; Li Chengjun; McWeeney Shannon; Sabourin Carol; Kawaoka Yoshihiro; Katze Michael G; Waters Katrina M

2011-01-01

308

Hatching response to temperature along a latitudinal gradient by the fairy shrimp Branchinecta lindahli (Crustacea; Branchiopoda; Anostraca) in culture conditions  

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Branchinecta lindahli is a broadly distributed fairy shrimp, reported from a range of temporary wetland habitat types in arid western North America. This species’ eggs hatch after the habitat dries, refills from seasonal rain, and receives a strong cold shock during the winter low temperatures. I studied phenotypic variation in temperature responses in cultures collected from four populations across 8° of latitude with low average temperatures ranging from -8 to 8°C. Time to m...

Christopher Rogers, D.

2014-01-01

309

?PKC Participates in the Endoplasmic Reticulum Stress-Induced Response in Cultured Cardiac Myocytes and Ischemic Heart  

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The cellular response to excessive endoplasmic reticulum (ER) stress includes the activation of signaling pathways, which lead to apoptotic cell death. Here we show that treatment of cultured cardiac myocytes with tunicamycin, an agent that induces ER stress, causes the rapid translocation of ?PKC to the ER. We further demonstrate that inhibition of ?PKC using the ?PKC-specific antagonist peptide, ?V1-1, reduces tunicamycin-induced apoptotic cell death, and inhibits expression of specific...

Qi, Xin; Vallentin, Alice; Churchill, Eric; Mochly-rosen, Daria

2007-01-01

310

Brassinosteroids control male fertility by regulating the expression of key genes involved in Arabidopsis anther and pollen development  

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The development of anther and pollen is important for male reproduction, and this process is coordinately regulated by many external and internal cues. In this study, we systematically examined the male reproductive phenotypes of a series of brassinosteroid biosynthetic and signaling mutants and found that, besides the expected cell-expansion defects, these mutants also showed reduced pollen number, viability, and release efficiency. These defects were related with abnormal tapetum and micros...

Ye, Qianqian; Zhu, Wenjiao; Li, Lei; Zhang, Shanshan; Yin, Yanhai; Ma, Hong; Wang, Xuelu

2010-01-01

311

The HD-ZIP IV transcription factor OCL4 is necessary for trichome patterning and anther development in maize.  

Science.gov (United States)

Among the genes controlling the differentiation and maintenance of epidermal cell fate are members of the HD-ZIP IV class family of plant-specific transcription factors, most of which are specifically expressed in the epidermis of tissues. Here, we report the functional analysis of the maize HD-ZIP IV gene OCL4 (outer cell layer 4) via the phenotypic analysis of two insertional mutants, and of OCL4-RNAi transgenic plants. In all three materials, the macrohairs, one of the three types of trichomes present on adult maize leaf blades, developed ectopically at the margin of juvenile and adult leaves. Consistent with this phenotype, OCL4 is expressed in the epidermis of the leaf blade, with a maximum at the margin of young leaf primordia. Expression of OCL4 in the model plant Arabidopsis under the control of the GLABRA2 (GL2) promoter, a member of the Arabidopsis HD-ZIP IV family involved in trichome differentiation, did not complement the gl2-1 mutant, but instead aggravated its phenotype. The construct also caused a glabrous appearance of rosette leaves in transformed control plants of the Ler ecotype, suggesting that OCL4 inhibits trichome development both in maize and Arabidopsis. Furthermore, insertional mutants showed a partial male sterility that is likely to result from the presence of an extra subepidermal cell layer with endothecium characteristics in the anther wall. Interestingly, the epidermis-specific OCL4 expression in immature anthers was restricted to the region of the anther locule where the extra cell layer differentiated. Taken together these results suggest that OCL4 inhibits trichome development and influences division and/or differentiation of the anther cell wall. PMID:19453441

Vernoud, Vanessa; Laigle, Guillaume; Rozier, Frédérique; Meeley, Robert B; Perez, Pascual; Rogowsky, Peter M

2009-09-01

312

Anther smut transmission in Silene latifolia and Silene dioica: Impact of host traits, disease frequency, and host density  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Predicting the dynamics of hosts and pathogens in natural systems requires a thorough understanding of the disease transmission process. It has been argued that, unlike for airborne diseases, the transmission of vector-borne diseases such as the anther smut fungus Microbotryum violaceum is a function of the frequency rather than the density of disease in a population. However, recent models indicate that frequency- dependent transmission of vectored diseases is only expected if the time requi...

Biere, A.; Honders, S. C.

1998-01-01

313

Male-fertility genes expressed in male flower buds of Silene latifolia include homologs of anther-specific genes.  

Science.gov (United States)

When the female plant of Silene latifolia is infected with the smut fungus Microbotryum violaceum, its rudimentary stamens develop into anthers which contain fungus teliospores instead of pollen. To identify genes required for maturation of anthers in S. latifolia, we performed a cDNA subtraction approach with healthy male buds and female buds infected with M. violaceum. We isolated five cDNA clones, which were preferentially expressed in healthy male buds during stages associated with a burst in tapetal activity. These five cDNAs are predicted to encode a mandelonitrile lyase protein (SlMDL1), a strictosidine synthase protein (SlSs), a glycosyl hydrolase 17 protein (SlGh17), a proline-rich protein APG precursor (SlAPG), and a chalcone-synthase-like protein (SlChs). All five genes showed expression in both healthy and fungus-infected male buds, but not expressed in either healthy or infected female buds. The first three genes were highly expressed in both tapetum and pollen grains while the last two genes were expressed only inside the tapetum of male flower buds. Phylogenetic analysis results showed that SlChs and SlGh17 belong to anther-specific subgroups of chalcone-synthase-like genes and glycosyl hydrolase 17 family genes, respectively. Our results suggest that the isolated five genes are related to the fertility of the anther leading to the development of fertile pollen. The smut fungus was not able to induce the expression of the five genes in the infected female buds. This raises the possibility that these genes are under the control of master gene(s) on the Y chromosome. PMID:16501309

Ageez, Amr; Kazama, Yusuke; Sugiyama, Ryuji; Kawano, Shigeyuki

2005-12-01

314

Ultrastructural studies on the sporogenous tissue and anther wall of Leucojum aestivum (amaryllidaceae) in different developmental stages  

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In this study, ultrastructures of anther wall and sporogenous tissue of Leucojum aestivum were investigated during different developmental stages. Cytomictic channels were seen between pollen mother cells during prophase I. Polar distribution was described in the organelle content of pollen mother cells and microspores in early phases of microsporogenesis and also in pollen mitosis. Active secretion was observed in tapetal cells. Previous reports about developmental stages of male gametophyte...

Nuran Ekici; Feruzan Dane

2012-01-01

315

Radiation-induced p53 protein response in the A549 cell line is culture growth-phase dependent  

International Nuclear Information System (INIS)

One role of the p53 tumor suppressor protein has been recently revealed. Kastan, M.B. reported that p53 protein accumulates in cells exposed to ionizing radiation. The accumulation of p53 protein is in response to DNA damage, most importantly double-strand breaks, that results from exposure to ionizing radiation. The rise in cellular p53 levels is necessary for an arrest in the G1 phase of the cell cycle to provide additional time for DNA repair. The p53 response has also been demonstrated to enhance PCNA-dependent repair. p53 is thus an important regulator of the cellular response to DNA-damaging radiation. From this data, it can be concluded that the magnitude of the p53 response is not dependent on the phase of culture growth

316

Radiation-induced p53 protein response in the A549 cell line is culture growth-phase dependent  

Energy Technology Data Exchange (ETDEWEB)

One role of the p53 tumor suppressor protein has been recently revealed. Kastan, M.B. reported that p53 protein accumulates in cells exposed to ionizing radiation. The accumulation of p53 protein is in response to DNA damage, most importantly double-strand breaks, that results from exposure to ionizing radiation. The rise in cellular p53 levels is necessary for an arrest in the G{sub 1} phase of the cell cycle to provide additional time for DNA repair. The p53 response has also been demonstrated to enhance PCNA-dependent repair. p53 is thus an important regulator of the cellular response to DNA-damaging radiation. From this data, it can be concluded that the magnitude of the p53 response is not dependent on the phase of culture growth.

Johnson, N.F.; Gurule, D.M.; Carpenter, T.R.

1995-12-01

317

Rice CYP703A3, a cytochrome P450 hydroxylase, is essential for development of anther cuticle and pollen exine.  

Science.gov (United States)

Anther cuticle and pollen exine act as protective envelopes for the male gametophyte or pollen grain, but the mechanism underlying the synthesis of these lipidic polymers remains unclear. Previously, a tapetum-expressed CYP703A3, a putative cytochrome P450 fatty acid hydroxylase, was shown to be essential for male fertility in rice (Oryza sativa L.). However, the biochemical and biological roles of CYP703A3 has not been characterized. Here, we observed that cyp703a3-2 caused by one base insertion in CYP703A3 displays defective pollen exine and anther epicuticular layer, which differs from Arabidopsis cyp703a2 in which only defective pollen exine occurs. Consistently, chemical composition assay showed that levels of cutin monomers and wax components were dramatically reduced in cyp703a3-2 anthers. Unlike the wide range of substrates of Arabidopsis CYP703A2, CYP703A3 functions as an in-chain hydroxylase only for a specific substrate, lauric acid, preferably generating 7-hydroxylated lauric acid. Moreover, chromatin immunoprecipitation and expression analyses revealed that the expression of CYP703A3 is directly regulated by Tapetum Degeneration Retardation, a known regulator of tapetum PCD and pollen exine formation. Collectively, our results suggest that CYP703A3 represents a conserved and diversified biochemical pathway for in-chain hydroxylation of lauric acid required for the development of male organ in higher plants. PMID:24798002

Yang, Xijia; Wu, Di; Shi, Jianxin; He, Yi; Pinot, Franck; Grausem, Bernard; Yin, Changsong; Zhu, Lu; Chen, Mingjiao; Luo, Zhijing; Liang, Wanqi; Zhang, Dabing

2014-10-01

318

Rat Sertoli cells acquire a beta-adrenergic response during primary culture.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Two-dimensional polyacrylamide gel electrophoresis and the radioligand (-)-[125I]iodopindolol (125I-Pin) have been used to study isoproterenol-dependent protein phosphorylation and beta-adrenergic receptor availability, respectively, in cultured Sertoli cells and freshly isolated seminiferous tubular segments of sexually immature and mature rats. Sertoli cells prepared from sexually immature rats show progressive 125I-Pin binding in primary cultures that correlates with isoproterenol-induced ...

Kierszenbaum, A. L.; Spruill, W. A.; White, M. G.; Tres, L. L.; Perkins, J. P.

1985-01-01

319

Response of Prochlorococcus ecotypes to co-culture with diverse marine bacteria  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Interactions between microorganisms shape microbial ecosystems. Systematic studies of mixed microbes in co-culture have revealed widespread potential for growth inhibition among marine heterotrophic bacteria, but similar synoptic studies have not been done with autotroph/heterotroph pairs, nor have precise descriptions of the temporal evolution of interactions been attempted in a high-throughput system. Here, we describe patterns in the outcome of pair-wise co-cultures between two ecologicall...

Sher, Daniel; Thompson, Jessie W.; Kashtan, Nadav; Croal, Laura; Chisholm, Sallie W.

2010-01-01

320

RESPONSE OF EMBRYOS OF SOME VARIETIES OF RICE FOR THEIR CALLUSING AND DIFFERENTIATION  

Directory of Open Access Journals (Sweden)

Full Text Available Rice is the main food of most of the countries of the world. To cope with the population explosion, conventional method of rice production seems inadequate. Hense, for this purpose; tissue culture technology has been introduced. Before applying any advanced study, such as anther culture, protoplast culture or genetic engineering etc., it is essential to work on the rice varieties from its embryo level. In this perspective, four varieties of rice had been undertaken for the response of their embryos on different concentrations of 2,4D, for their callusing and upon different concentrations of IAA and KN for differentiation. Out of the four varieties of rice, Tulsi and Kanak embryos showed the best response for their callusing at the strength 6 mg/l of 2,4D - 40% and 22% respectively, which is followed by Pusa-Basmati and Birsa 101 embryos. Almost all the varieties showed their callusing more or less at all the strength of 2,4D taken into investigation. But the strength 6 mg/l was the best strength of 2,4D as upon this strength, all the varieties showed their callusing response. On the other hand, embryo derived callus when transferrred to differentiating medium MS + IAA (2 mg/l + KN(4mg/l gave the best result.

R.P.SINGH

2007-01-01

 
 
 
 
321

Response of normal human dermal fibroblasts in culture to very low dose rates of chronic irradiation  

International Nuclear Information System (INIS)

In vitro cell cultures were submitted to low doses of chronic external irradiation. Cultures were exposed for 8 days to 60 Co source by growing the cells in culture flasks, 10 cm above the irradiation source (dose rate: 6.25 mGy/day, i.e. 50 mGy/8 days). Human dermal fibroblast proliferation, protein and DNA contents were undisturbed under irradiation. In the same way, the transmembrane resting potential values of about 200 single cells, measured with a glass microelectrode, were similar in irradiated cells (9.4±4.9 eV) and controls (10.2±2.0 eV) on the 7th day of the culture. Glucose metabolism was investigated through the activity of G6P-DH (a key enzyme of the pentose phosphate shunt) and the activities of GAP-DH and pyruvate kinase (key enzymes of glycolysis pathway). Assays performed over a complete growth curve showed that chronic irradiation did not induce significant change of G6P-DH but GAP-DH and pyruvate kinase appeared transiently inhibited (up to 25%) during the early exponential growth phase. Catalase activity was not significantly perturbed under irradiation. A correlation between the increase of total catalase activity in cultures and the GAP-DH normal activity restoration was observed, probably related to a decrease of SH-group oxidation

322

Changes in cell biochemistry in response to culture of protoplasts with oxygenated perfluorocarbon.  

Science.gov (United States)

Superoxide dismutase (superoxide oxidoreductase; EC 1.15.1.1; SOD) was measured in enzymatically isolated protoplasts of Salpiglossis sinuata following culture in aqueous nutrient medium overlaying oxygen-gassed perfluorodecalin (Flutec PP6; BNFL Fluorochemicals, UK). SOD was extracted from harvested, lysed protoplast-derived cells after 1, 3, 7 and 14 days of culture and assayed spectrophotometrically. Protoplasts cultured with oxygenated PFC (+/- s.e.m, n = 5) showed significant increases in mean SOD activity to 4.2 +/- 0.1 U after 1 day (P < 0.05) and 9.3 +/- 0.7 U after 3 days (P < 0.01), with a fall in mean SOD after 7 days (5.1 +/- 0.9 U), similar to control. The decrease in SOD after 7 days correlated closely with a progressive fall in pO2 in the PFC phase over the same period. In contrast, control protoplasts (medium alone) or protoplasts cultured in medium overlaying non-oxygenated PFC showed no significant changes in mean SOD activity over the 14-day culture assessment period. PMID:9352063

Wardrop, J; Edwards, C M; Lowe, K C; Davey, M R; Power, J B

1997-11-01

323

Organisational Culture in Innovative Small to Medium Sized Enterprises (SMEs) : Leadership’s Responsibilities when Implementing Change as a Result of M&As  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study investigates what culturally related responsibilities leaders in innovative SMEs have when preparing employees prior to M&As in order to mitigate drawbacks due to culturally related discrepancies. The findings of this study especially confirm previous studies on culturally related difficulties in change management by emphasising the significant meaning of evaluating soft factors prior to change. The study was conducted by examining an innovative SME in the telecom industry that...

Rasmussen, Sara

2013-01-01

324

Effects of Culture and Education on Ethical Responses on Our Global Society  

Directory of Open Access Journals (Sweden)

Full Text Available Two trends that affect communications are prevalent today: a focus on ethics in the U.S. business operations and an increasingly global society and marketplace. This research project brings together these trends to gain a more in-depth understanding of the impact of culture on ethical education. By surveying students in six countries around the globe, this study was able to get at the divergent cultural frameworks utilized in ethical decision making. The results offer a significant contribution to our understanding of the cross-cultural implications on ethical values in the business context. This understanding provides unique insights into ethics education and the need for a contextual understanding of applied ethics.

Comiskey, Christina Pryor

2012-01-01

325

The response of human nasal and bronchial organotypic tissue cultures to repeated whole cigarette smoke exposure.  

Science.gov (United States)

Exposure to cigarette smoke (CS) is linked to the development of respiratory diseases, and there is a need to understand the mechanisms whereby CS causes damage. Although animal models have provided valuable insights into smoking-related respiratory tract damage, modern toxicity testing calls for reliable in vitro models as alternatives for animal experimentation. We report on a repeated whole mainstream CS exposure of nasal and bronchial organotypic tissue cultures that mimic the morphological, physiological, and molecular attributes of the human respiratory tract. Despite the similar cellular staining and cytokine secretion in both tissue types, the transcriptomic analyses in the context of biological network models identified similar and diverse biological processes that were impacted by CS-exposed nasal and bronchial cultures. Our results demonstrate that nasal and bronchial tissue cultures are appropriate in vitro models for the assessment of CS-induced adverse effects in the respiratory system and promising alternative to animal experimentation. PMID:25297719

Talikka, Marja; Kostadinova, Radina; Xiang, Yang; Mathis, Carole; Sewer, Alain; Majeed, Shoaib; Kuehn, Diana; Frentzel, Stefan; Merg, Celine; Geertz, Marcel; Martin, Florian; Ivanov, Nikolai V; Peitsch, Manuel C; Hoeng, Julia

2014-11-01

326

A comparison of cytokine production in 2-dimensional and 3-dimensional cultures of bone marrow stromal cells of multiple myeloma patients in response to RPMI8226 myeloma cells.  

Directory of Open Access Journals (Sweden)

Full Text Available We examined cytokine production by bone marrow stromal cells (BMSCs of patients with multiple myeloma (MM in response to contact with myeloma RPMI8226 cells in standard 2-dimensional (2D cultures and in 3-dimensional (3D cultures on a gelatine sponge scaffold. It was detected that BMSCs in the 3D cultures produced more IL-11 and HGF and less IL-10 than in the 2D cultures. Moreover, RPMI8226 cells after contact with BMSCs in 3D cultures produced more sIL-6R than in the classic 2D cultures. We concluded that 3D cultures of BMSCs with myeloma cells offered a promising model for in vitro examination of interactions between myeloma cells and the bone marrow stroma and for examination of potent antimyeloma agents.

Jacek Roli?ski

2009-05-01

327

Concentration-dependent gene expression responses to flusilazole in embryonic stem cell differentiation cultures  

International Nuclear Information System (INIS)

The murine embryonic stem cell test (EST) is designed to evaluate developmental toxicity based on compound-induced inhibition of embryonic stem cell (ESC) differentiation into cardiomyocytes. The addition of transcriptomic evaluation within the EST may result in enhanced predictability and improved characterization of the applicability domain, therefore improving usage of the EST for regulatory testing strategies. Transcriptomic analyses assessing factors critical for risk assessment (i.e. dose) are needed to determine the value of transcriptomic evaluation in the EST. Here, using the developmentally toxic compound, flusilazole, we investigated the effect of compound concentration on gene expression regulation and toxicity prediction in ESC differentiation cultures. Cultures were exposed for 24 h to multiple concentrations of flusilazole (0.54-54 ?M) and RNA was isolated. In addition, we sampled control cultures 0, 24, and 48 h to evaluate the transcriptomic status of the cultures across differentiation. Transcriptomic profiling identified a higher sensitivity of development-related processes as compared to cell division-related processes in flusilazole-exposed differentiation cultures. Furthermore, the sterol synthesis-related mode of action of flusilazole toxicity was detected. Principal component analysis using gene sets related to normal ESC differentiation was used to describe the dynamics of ESC differentiation, defined as the 'differentiation track'. The conceas the 'differentiation track'. The concentration-dependent effects on development were reflected in the significance of deviation of flusilazole-exposed cultures from this transcriptomic-based differentiation track. Thus, the detection of developmental toxicity in EST using transcriptomics was shown to be compound concentration-dependent. This study provides further insight into the possible application of transcriptomics in the EST as an improved alternative model system for developmental toxicity testing.

328

Regeneração in vitro de anteras de arroz irrigado (Oryza sativa L. e mapeamento de QTL associado In vitro regeneration of irrigated rice (Oryza sativa L. anthers and detection of associated QTL  

Directory of Open Access Journals (Sweden)

Full Text Available A baixa taxa de regeneração in vitro de alguns cultivares de arroz da subespécie indica limita a utilização de técnicas de cultura de anteras como ferramenta para o desenvolvimento de novos cultivares. A identificação de regiões genômicas associadas à formação de calos e regeneração de plantas, a partir do cultivo de anteras, poderá permitir a transferência do caráter por seleção assistida. Duas populações de retrocruzamento foram utilizadas para o mapeamento genético e estudo destes caracteres, sendo Taipei 309// BRS 7 "Taim"/Taipei 309 (53 genótipos e BRS 7 "Taim"// BRS 7 "Taim"/Taipei 309 (74 genótipos. Duzentas anteras imaturas de cada genótipo utilizado no estudo foram inoculadas em meio NL líquido e, após 40 dias, os calos formados foram transferidos para o meio MS sólido para regeneração de plantas. Todas as plantas doadoras de anteras foram usadas na extração de DNA genômico e sete primers RAPD foram utilizados na geração de marcadores para a construção dos mapas de ligação dos retrocruzamentos estudados. A taxa de formação de calos variou de 2,27 a 3,36% e a taxa de regeneração de plantas 1,38 a 1,82%, não se diferenciando significativamente. Seis grupos de ligação foram obtidos, três em cada população. Um QTL com LOD 3,10 foi detectado para o caráter formação de calos na população Taipei 309 // BRS 7 "Taim" / Taipei 309. Nenhum QTL foi detectado para a característica regeneração de plantas.The low in vitro regeneration of some indica rice cultivars, limits the use of anther culture techniques as a tool to reduce the time for releasing new cultivars. The identification of genomic regions associated with callus formation and in vitro regeneration from anther culture, will facilitate selection of these traits through marker assisted techniques. Two backcross populations were used to study and map these traits, Taipei 309// BRS 7 "Taim"/Taipei 309 (53 genotypes and BRS 7 "Taim"// BRS 7 "Taim"/Taipei 309 (74 genotypes. Two hundred immature anthers, from each genotype used in this study, were inoculated in liquid NL medium for callus induction and, after 40 days, the formed callus were transferred to solid MS medium for plant regeneration. Each anther donor plant was used for DNA extraction and seven RAPD primers were used to assess genomic regions associated to callus formation and plant regeneration. As results, callus formation ranged from 2.27 up to 3.36% and plant regeneration ranged from 1.38 up to 1.82%, no significant differences were observed. Six linkage groups were obtained, being three from each population. One QTL was detected associated to callus formation, with LOD score 3.10, in the population Taipei 309 // BRS 7 "Taim" / Taipei 309. No QTL association was detected to the trait plant regeneration.

Sérgio Dias Lannes

2004-10-01

329

Regeneração in vitro de anteras de arroz irrigado (Oryza sativa L.) e mapeamento de QTL associado / In vitro regeneration of irrigated rice (Oryza sativa L.) anthers and detection of associated QTL  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A baixa taxa de regeneração in vitro de alguns cultivares de arroz da subespécie indica limita a utilização de técnicas de cultura de anteras como ferramenta para o desenvolvimento de novos cultivares. A identificação de regiões genômicas associadas à formação de calos e regeneração de plantas, a pa [...] rtir do cultivo de anteras, poderá permitir a transferência do caráter por seleção assistida. Duas populações de retrocruzamento foram utilizadas para o mapeamento genético e estudo destes caracteres, sendo Taipei 309// BRS 7 "Taim"/Taipei 309 (53 genótipos) e BRS 7 "Taim"// BRS 7 "Taim"/Taipei 309 (74 genótipos). Duzentas anteras imaturas de cada genótipo utilizado no estudo foram inoculadas em meio NL líquido e, após 40 dias, os calos formados foram transferidos para o meio MS sólido para regeneração de plantas. Todas as plantas doadoras de anteras foram usadas na extração de DNA genômico e sete primers RAPD foram utilizados na geração de marcadores para a construção dos mapas de ligação dos retrocruzamentos estudados. A taxa de formação de calos variou de 2,27 a 3,36% e a taxa de regeneração de plantas 1,38 a 1,82%, não se diferenciando significativamente. Seis grupos de ligação foram obtidos, três em cada população. Um QTL com LOD 3,10 foi detectado para o caráter formação de calos na população Taipei 309 // BRS 7 "Taim" / Taipei 309. Nenhum QTL foi detectado para a característica regeneração de plantas. Abstract in english The low in vitro regeneration of some indica rice cultivars, limits the use of anther culture techniques as a tool to reduce the time for releasing new cultivars. The identification of genomic regions associated with callus formation and in vitro regeneration from anther culture, will facilitate sel [...] ection of these traits through marker assisted techniques. Two backcross populations were used to study and map these traits, Taipei 309// BRS 7 "Taim"/Taipei 309 (53 genotypes) and BRS 7 "Taim"// BRS 7 "Taim"/Taipei 309 (74 genotypes). Two hundred immature anthers, from each genotype used in this study, were inoculated in liquid NL medium for callus induction and, after 40 days, the formed callus were transferred to solid MS medium for plant regeneration. Each anther donor plant was used for DNA extraction and seven RAPD primers were used to assess genomic regions associated to callus formation and plant regeneration. As results, callus formation ranged from 2.27 up to 3.36% and plant regeneration ranged from 1.38 up to 1.82%, no significant differences were observed. Six linkage groups were obtained, being three from each population. One QTL was detected associated to callus formation, with LOD score 3.10, in the population Taipei 309 // BRS 7 "Taim" / Taipei 309. No QTL association was detected to the trait plant regeneration.

Sérgio Dias, Lannes; Paulo Dejalma, Zimmer; Antonio Costa de, Oliveira; Fernando Irajá Félix de, Carvalho; Eduardo Alano, Vieira; Ariano Martins de, Magalhães Junior; Maurício Marini, Kopp; Fábio Almeida de, Freitas.

1355-13-01

330

Extensive divergence between mating-type chromosomes of the anther-smut fungus.  

Science.gov (United States)

Genomic regions that determine mating compatibility are subject to distinct evolutionary forces that can lead to a cessation of meiotic recombination and the accumulation of structural changes between members of the homologous chromosome pair. The relatively recent discovery of dimorphic mating-type chromosomes in fungi can aid the understanding of sex chromosome evolution that is common to dioecious plants and animals. For the anther-smut fungus, Microbotryum lychnidis-dioicae (= M. violaceum isolated from Silene latifolia), the extent of recombination cessation on the dimorphic mating-type chromosomes has been conflictingly reported. Comparison of restriction digest optical maps for the two mating-type chromosomes shows that divergence extends over 90% of the chromosome lengths, flanked at either end by two pseudoautosomal regions. Evidence to support the expansion of recombination cessation in stages from the mating-type locus toward the pseudoautosomal regions was not found, but evidence of such expansion could be obscured by ongoing processes that affect genome structure. This study encourages the comparison of forces that may drive large-scale recombination suppression in fungi and other eukaryotes characterized by dimorphic chromosome pairs associated with sexual life cycles. PMID:23150606

Hood, Michael E; Petit, Elsa; Giraud, Tatiana

2013-01-01

331

Phylogenetic evidence of host-specific cryptic species in the anther smut fungus.  

Science.gov (United States)

Cryptic structure of species complexes confounds an accurate accounting of biological diversity in natural systems. Also, cryptic sibling species often become specialized to different ecological conditions, for instance, with host specialization by cryptic parasite species. The fungus Microbotryum violaceum causes anther smut disease in plants of Caryophyllaceae, and the degree of specialization and gene flow between strains on different hosts have been controversial in the literature. We conducted molecular phylogenetic analyses on M. violaceum from 23 host species and different geographic origins using three single-copy nuclear genes (beta-tub, gamma-tub, and Ef1alpha). Congruence between the phylogenies identified several lineages that evolved independently for a long time. The lineages had overlapping geographic ranges but were highly specialized on different hosts. These results thus suggest that M. violaceum is a complex of highly specialized sibling species. Two incongruencies between the individual gene phylogenies and one intragene recombination event were detected at basal nodes, suggesting ancient introgression events or speciation events via hybridizations. However, incongruencies and recombination were not detected among terminal branches, indicating that the potentials for cross-infection and experimental hybridization are often not sufficient to suggest that introgressions would likely persist in nature. PMID:17300424

Le Gac, Mickael; Hood, Michael E; Fournier, Elisabeth; Giraud, Tatiana

2007-01-01

332

A Story within a Story: Culturally Responsive Schooling and American Indian and Alaska Native Achievement in the National Indian Education Study  

Science.gov (United States)

There have been numerous calls to increase quantitative studies examining the role of culturally responsive schooling (CRS) on American Indian and Alaska Native (AIAN) achievement. The National Indian Education Study (NIES) is the only large-scale study focused on (AIAN) students' cultural experiences within the context of schools. Given…

Lopez, Francesca A.; Vasquez Heilig, Julian; Schram, Jacqueline

2013-01-01

333

An Investigation into the Relationship between Culturally Responsive Teaching and Fourth-, Fifth-, and Sixth-Grade Student Performance on the California Standards Tests: Teacher Perceptions, Definitions, and Descriptions  

Science.gov (United States)

This mixed-methods study is an investigation into the relationship between culturally responsive teaching and fourth-, fifth-, and sixth-grade student performance on the California Standards Tests (CSTs). The significance of this research lies in its evaluation of the way that the self-perceived cultural proficiency level of the teacher and…

Coghlan, Robert R.

2011-01-01

334

Activation of antioxidant response element in mouse primary cortical cultures with sesquiterpene lactones isolated from Tanacetum parthenium.  

Science.gov (United States)

Tanacetum parthenium produces biologically active sesquiterpene lactones (SL). Nuclear factor E2-related factor 2 (Nrf2) is a transcription factor known to activate a series of genes termed the antioxidant response element (ARE). Activation of Nrf2/ARE may be useful for the treatment of neurodegenerative disease. In this study we isolated 11 SL from T. parthenium with centrifugal partition chromatography and semipreparative HPLC. Compounds were screened in vitro for their ability to activate the ARE on primary mouse cortical cultures as well as for their toxicity towards the cultures. All SL containing the ?-methylene-?-lactone moiety were able to activate the ARE and cause cellular toxicity. The structure-activity relationship among the SL isolated indicates that the guaianolides were more active and when lacking the endoperoxide functionality less toxic then the germacranolides. PMID:22923197

Fischedick, Justin T; Standiford, Miranda; Johnson, Delinda A; De Vos, Ric C H; Todorovi?, Sla?ana; Banjanac, Tijana; Verpoorte, Rob; Johnson, Jeffrey A

2012-11-01

335

Cultura organizacional y la responsabilidad social en las universidades públicas / Organizational Culture and Social Responsibility in Public Universities  

Scientific Electronic Library Online (English)

Full Text Available SciELO Venezuela | Language: Spanish Abstract in spanish El propósito del artículo es determinar la relación entre la cultura organizacional y la responsabilidad social en las universidades públicas de la Costa Oriental del Lago del estado Zulia (COL). La población estuvo conformada por el personal Directivo, Docente y Administrativo de las universidades [...] públicas de la Costa Oriental del Lago, así como también los representantes de las Asociaciones de Vecinos. Los resultados encontrados evidencian que existe una relación directamente proporcional y moderada entre los elementos de la cultura y la responsabilidad social de las universidades en estudio, situación que explica la relación positiva fuerte. Considerando estos hallazgos, se sugieren una serie de lineamientos estratégicos direccionados hacia cuatro categorías: funcionamiento, de educación, cognoscitivos y epistemológicos y sociales. Concluyéndose que existen deficiencias en la presencia de elementos como: creencias, valores, rituales, lenguaje e historia, que conforman la cultura, lo cual refleja que la percepción que el personal posee, es el de una cultura corporativa moderadamente débil. Abstract in english The purpose of the study was to determine the relation between organizational culture and social responsibility in public universities on the C.O.L. The population consisted of directive, educational and administrative personal from public universities on the East Coast of Lake Maracaibo, plus repre [...] sentatives from neighbors’ associations. Results showed that a directly proportional and moderate relationship exists between elements of the culture and social responsibility at the universities under study, a situation that explains the strong, positive relation. Considering these findings, a series of strategic guidelines was suggested, directed toward four categories: functional, educational, cognitive, epistemological and social. Conclusions were that some deficiencies exist in the presence of elements that constitute culture, such as beliefs, values, rituals, language and history, indicating that the perception the personnel holds is that of a slightly weak corporative culture.

Cira de, Pelekais; Mariela, Rivadeneira.

2008-04-01

336

Increasing School Success Among Aboriginal Students: Culturally Responsive Curriculum or Macrostructural Variables Affecting Schooling?  

Science.gov (United States)

Aspects of Aboriginal cultural knowledge/perspectives were integrated into the Grade 9 social studies curriculum of a high school in a western Canadian city to appraise the impact on academic achievement, class attendance, and school retention among specific groups of Aboriginal students. The results suggest cautious optimism about increasing…

Kanu, Yatta

2007-01-01

337

Culturally Responsive Pedagogy: Connecting New Zealand Teachers of Science with Their Maori Students  

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This paper illustrates how important changes can occur in science learning and teaching if teachers take the trouble to understand and respect the cultural worlds of Indigenous students, and incorporate something of this understanding within their teaching practice. Ten teachers participated in a specially-designed one-year university postgraduate…

Glynn, Ted; Cowie, Bronwen; Otrel-Cass, Kathrin; Macfarlane, Angus

2010-01-01

338

COASTAL SALT MARSH COMMUNITY CHANGE IN NARRAGANSETT BAY IN RESPONSE TO CULTURAL EUTROPHICATION  

Science.gov (United States)

Coastal salt marshes are susceptible to cultural eutrophication, particularly the over-enrichment of nitrogen, because they are often located where surface water and groundwater discharge into estuaries. In this report, the current areal extent of coastal salt marshes in Narrag...

339

Cultural beliefs about rape and victims' response in three ethnic groups.  

Science.gov (United States)

Cultural definitions of rape were assessed among 101 African-American, Hispanic, and non-Hispanic white female rape victims and 89 nonvictims matched for ethnicity, age, marital status, and socioeconomic status. Hispanics scored highest and whites lowest both in perceived community victim-blaming and in victims' psychological distress. Social and treatment implications are discussed. PMID:8267103

Lefley, H P; Scott, C S; Llabre, M; Hicks, D

1993-10-01

340

Evaluating Autism Diagnostic and Screening Tools for Cultural and Linguistic Responsiveness  

Science.gov (United States)

While clear guidelines and best practices exist for the assessment of autism spectrum disorders (ASD), little information is available about assessing for ASD in culturally and linguistically diverse (CLD) populations. CLD populations might be misidentified and under-identified with ASD due to the assessment practices that we employ. Four autism…

Harris, Bryn; Barton, Erin E.; Albert, Chantel

2014-01-01

 
 
 
 
341

Suicidal, Abused African American Women's Response to a Culturally Informed Intervention  

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Objective: This study examined (a) the efficacy of a manualized, culturally informed, empowerment-focused psychoeducational group intervention (Nia) designed in accord with the theory of triadic influence or treatment as usual (TAU) for reducing psychological symptomatology (suicidal ideation, depressive symptoms, posttraumatic stress symptoms,…

Kaslow, Nadine J.; Leiner, Amy S.; Reviere, Susan; Jackson, Emily; Bethea, Kafi; Bhaju, Jeshmin; Rhodes, Miesha; Gantt, Min-Jung; Senter, Herman; Thompson, Martie P.

2010-01-01

342

Culture Media Optimization through Response Surface Methodology for in vitro Shoot Bud Development of Solanum melongena L. for Micropropagation  

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Full Text Available Response surface methodology was used for the optimization of shoot bud response and shoot bud induction in leaf explants of Solanum melongena cultivar Arka Shirish. Three independent variables were evaluated for shoot bud response and shoot bud induction. The variables include the concentrations of nitrogen (N2, sucrose and growth regulator thidiazuron (TDZ. The shoot bud response for cultured explant was optimized at 4.34 g/l of total nitrogen, 2.65% of sucrose and 0.67 mg/l of TDZ with 95% response. The optimum medium conditions for shoot bud induction was found to be Murashige and Skoog (MS basal medium supplemented with 4.02 g/l of total nitrogen, 2.36% of sucrose and 1.0 mg/l of TDZ with 10 number of bud per explant. The shoot buds so formed were elongated in 0.5 mg/l 2,3,5-Triiodobenzoic acid (TIBA and 0.1 mg/l Gibberellic acid (GA3. The elongated shoots were rooted in MS with 1 mg/l Indole-3-butyric acid (IBA. The rooted plants were transferred to pots with farmyard manure upon hardening. This study has validation value for optimization of micropropagation protocol and is further useful in genetic transformation studies for Solanum melongena variety Arka Shirish to maximize regenerative response for automation.

Sila Bhattacharya

2011-11-01

343

Identification of the tapetum/microspore-specific promoter of the pathogenesis-related 10 gene and its regulation in the anther of Lilium longiflorum.  

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A tapetum/microspore-specific pathogenesis-related (PR) 10 gene was previously identified in lily (Lilium longiflorum Thunb.) anthers. In situ hybridization and RNA blot analysis indicated that the lily PR10 genes are expressed specifically and differentially in the tapetum of the anther wall and in microspores during anther development. The accumulation of PR10 transcripts was exogenously induced by gibberellic acid (GA) and was suppressed by ethylene. Studies using inhibitors of GA and ethylene revealed that the lily PR10 is modulated by an antagonistic interaction between GA and ethylene. The treatment of norbornadien, an ethylene inhibitor, caused the tapetum to become densely cytoplasmic and highly polarized, whereas uniconazole, an inhibitor of GA biosynthesis, arrested tapetal development to a status close to that of control. The expression of the lily PR10g promoter in transgenic Arabidopsis was determined using the ?-glucuronidase (GUS) reporter gene indicated that the decisive fragment required for anther specificity is located -1183 bp to -880 bp upstream of the transcription start site. The PR10gPro::barnase transgenic lines exhibited complete male sterility because of the disruption of the tapetum and the deformation of microspore/pollen. The anther specificity of lily PR10 highlights the importance of the tapetum/microspore-specific PR10g promoter for future biotechnological and agricultural applications. PMID:24388523

Hsu, Ssu-Wei; Liu, Ming-Che; Zen, Kuo-Chang; Wang, Co-Shine

2014-02-01

344

Effects of Field Plot Size on Variation in White Flower Anther Injury by Tarnished Plant Bug for Host Plant Resistance Evaluations in Arkansas Cotton  

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Full Text Available Field trials conducted in 2008 and 2009 investigated whether plot size affects incidence of white flower anther injury by tarnished plant bug (Lygus lineolaris (Palisot de Beauvois in host plant resistance (HPR evaluations. The three cotton lines evaluated in the trial included a susceptible frego bract line (RBCDHGPIQH-197 and 2 standards, SureGrow (SG 105 and Deltapine (DP 393. Samplers monitored white flower anther injury between single row mini-plots embedded within multiple row max-plots. A sub-section of the max-plots was sprayed with insecticides to evaluate these tactics on altering the incidence of white flower anther injury. Plant bug numbers were very low in 2008, while infestation levels were higher in 2009. Significantly higher numbers of flowers with anther injury were observed in both years in the susceptible frego bract line compared to SG 105 and DP 393 lines. In both years, anther injury levels were similar in the max- and mini-plots, with lower levels observed in max-sprayed plots. The white flower monitoring procedure is a consistent indicator of adult plant bug preferences and is not influenced by plot size or interspersions of cultivar lines among plots.

Jeffrey Willers

2014-02-01

345

Identification and expression analysis of methyl jasmonate responsive ESTs in paclitaxel producing Taxus cuspidata suspension culture cells  

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Full Text Available Abstract Background Taxol® (paclitaxel promotes microtubule assembly and stabilization and therefore is a potent chemotherapeutic agent against wide range of cancers. Methyl jasmonate (MJ elicited Taxus cell cultures provide a sustainable option to meet the growing market demand for paclitaxel. Despite its increasing pharmaceutical importance, the molecular genetics of paclitaxel biosynthesis is not fully elucidated. This study focuses on identification of MJ responsive transcripts in cultured Taxus cells using PCR-based suppression subtractive hybridization (SSH to identify genes involved in global pathway control. Results Six separate SSH cDNA libraries of paclitaxel-accumulating Taxus cuspidata P991 cell lines were constructed at three different post-elicitation time points (6h, 18h and 5 day to identify genes that are either induced or suppressed in response to MJ. Sequencing of 576 differentially screened clones from the SSH libraries resulted in 331 unigenes. Functional annotation and Gene Ontology (GO analysis of up-regulated EST libraries showed enrichment of several known paclitaxel biosynthetic genes and novel transcripts that may be involved in MJ-signaling, taxane transport, or taxane degradation. Macroarray analysis of these identified genes unravelled global regulatory expression of these transcripts. Semi-quantitative RT-PCR analysis of a set of 12 candidate genes further confirmed the MJ-induced gene expression in a high paclitaxel accumulating Taxus cuspidata P93AF cell line. Conclusions This study elucidates the global temporal expression kinetics of MJ responsive genes in Taxus suspension cell culture. Functional characterization of the novel genes identified in this study will further enhance the understanding of paclitaxel biosynthesis, taxane transport and degradation.

Lenka Sangram K

2012-04-01

346

Developing a culturally responsive breast cancer screening promotion with Native Hawaiian women in churches.  

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This article presents findings from research to develop the promotional component of a breast cancer screening program for Native Hawaiian women associated with historically Hawaiian churches in medically underserved communities.The literature on adherence to health recommendations and health promotions marketing guided inquiry on screening influences. Focus groups and individual interviews patterned on the culturally familiar practice of talk story were conducted with 60 Hawaiian women recruited through religious and social organizations.Text data were analyzed with an incremental process involving content analysis and Airhihenbuwa's PEN-3 model. Key informants and senior colleagues reviewed preliminary findings to ensure accuracy of interpretation. Findings reflect collectivist values at the intersection of indigenous Hawaiian culture and religiosity. Inclusion of messages that encourage holistic health across the intergenerational continuum of extended family and fictive kin, reinforcement from spiritual leaders, and testimonials of cancer survivors and family members may facilitate Hawaiian women's screening intent. PMID:18773792

Ka'opua, Lana Sue

2008-08-01

347

Synaptic currents and transmitter responses in human NT2 neurons differentiated in aggregate culture.  

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Postmitotic neurons were generated from the human NT2 teratocarcinoma cell line in a novel cell aggregate differentiation procedure. The NT2 model neurons express punctate immunoreactivity for synapsin and for cell markers related to GABAergic and glutamatergic neurotransmission. Using the outside-out patch-clamp configuration, we characterized the kinetics of currents elicited by a rapid application of the amino acid neurotransmitters. Moreover, we detected spontaneous postsynaptic currents in glia free cell cultures that may result from the firing activity of glutamatergic and GABAergic NT2 neurons. These cultured spontaneously active networks may be a useful tool to analyze factors that modulate the formation and efficacy of synapses between human neurons. PMID:19895870

Podrygajlo, Grzegorz; Song, Yunping; Schlesinger, Friedrich; Krampfl, Klaus; Bicker, Gerd

2010-01-14

348

Interval Nutrient Pulses Responses of Compatitive Culture Experiment: Chaetoceros Sp. Thallassiosira allenii (Takano, Gomphosphaeria Sp.  

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Full Text Available As phytoplankton are indisputably a major component of many food webs, estimating their abundance, biomass and growth rate has been an essential component of marine studies. The aim of this study is to establish the effects of different nutrient pulses on the cell size and biovolumes in competetive experiments of marine phytoplakton that was cultured from natural seawater. The growth of natural pytoplankton populations taken from Izmir bay (Aegean sea, Turkey was observed for 6 different nutrient pulse periods (4, 8, 12, 24, 48 and 96 h and determined Chl a, mean cell sizes and biovolumes. Thallassiosira allenii (Takano, Chaetoceros sp. and Gomphosphaeria sp. were dominated all pulse periods during the batch culture experiment. Nutrient pulses T. allenii and Chaetoceros sp. cells enlarged their biovolumes with the extension of pulse period, Gomphosphaeria sp. cells was not.

Goknur Sisman Aydin

2012-01-01

349

Social involvement and development as a response to the campus student culture  

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Given the widely accepted notion of whole person education in Confucian societies such as Hong Kong, Mainland China and Singapore, it is surprising that research literature originated in these societies pays little attention to how students learn and develop through out-of-class experiences at university. There is little research evidence on how the prevailing culture among student social communities (residential halls and student societies/clubs) influences students' social involvement and d...

Yang, M.; Chau, Awl

2011-01-01

350

Banking culture and collective responsibility: A memorandum to the UK Parliamentary Commission on Banking Standards  

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Basic assumptions • There is wide interest in connecting issues of (i) occupational culture, (ii) compliance/ misconduct, (iii) remuneration and (iv) clawback (the bonus/malus debate). • Individual-focussed measures (supervision, remuneration and measures in civil or criminal law) must be supplemented by a wider, whole-firm regulatory strategy. • Whilst attention has been drawn to ‘the tone at the top’, ‘the tone in the middle’ and ‘the tone at the bottom’ are as important. ...

Dorn, N.

2013-01-01

351

Effect of diclofenac and antidepressants on the inflammatory response in astrocyte cell culture.  

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Central nervous system (CNS) has a completely separate immune system that communicates with the neurons by small molecules called cytokines. Cytokines are involved in many crucial processes in neuron including cell metabolism and neurotransmitter synthesis. It has been reported that cytokine imbalance is involved in the progression of many CNS diseases such as neuropsychiatric disorders (depression, schizophrenia, autism, and bipolar disorder) and neurodegenerative disorders (Parkinson's and Alzheimer's disease). Here, the effects of diclofenac, different antidepressants (sertraline, venlafaxine, and fluvoxamine), and vitamin B? (pyridoxine) on IL-10 and tumor necrosis factor-? (TNF-?) change with and without immune challenges with lipopolysaccharide (LPS) were investigated in in vitro culture of astrocytes from 2-day-old Swiss-Albino mice. Diclofenac and Sertraline significantly (p cytokine (IL-10) while suppress (p 0.05) TNF-? in the astrocyte culture. Antidepressant (sertraline) showed positive effects (increased IL-10 and reduced TNF-? level) possibly through the suppression of Th1 lymphocytes and monocytes and stimulation of Th2 lymphocytes and monocytes/macrophages. NSAID (diclofenac) showed positive immune regulation effect possibly through the inhibition of cyclo-oxygenase enzyme. Based on these findings, it may conclude that, diclofenac and antidepressants (sertraline) may positively contribute in the cytokine production in astrocyte cell culture. PMID:23896940

Al-Amin, Md Mamun; Uddin, Mir Muhammad Nasir; Rahman, Md Mahbubur; Reza, Hasan Mahmud; Rana, Md Sohel

2013-12-01

352

Effects of Polysaccharide Elicitors on Secondary Metabolite Production and Antioxidant Response in Hypericum perforatum L. Shoot Cultures  

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The effects of polysaccharide elicitors such as chitin, pectin, and dextran on the production of phenylpropanoids (phenolics and flavonoids) and naphtodianthrones (hypericin and pseudohypericin) in Hypericum perforatum shoot cultures were studied. Nonenzymatic antioxidant properties (NEAOP) and peroxidase (POD) activity were also observed in shoot extracts. The activities of phenylalanine ammonia lyase (PAL) and chalcone-flavanone isomerase (CHFI) were monitored to estimate channeling in phenylpropanoid/flavonoid pathways of elicited shoot cultures. A significant suppression of the production of total phenolics and flavonoids was observed in elicited shoots from day 14 to day 21 of postelicitation. This inhibition of phenylpropanoid production was probably due to the decrease in CHFI activity in elicited shoots. Pectin and dextran promoted accumulation of naphtodianthrones, particularly pseudohypericin, within 21 days of postelicitation. The enhanced accumulation of naphtodianthrones was positively correlated with an increase of PAL activity in elicited shoots. All tested elicitors induced NEAOP at day 7, while chitin and pectin showed increase in POD activity within the entire period of postelicitation. The POD activity was in significantly positive correlation with flavonoid and hypericin contents, suggesting a strong perturbation of the cell redox system and activation of defense responses in polysaccharide-elicited H. perforatum shoot cultures.

Gadzovska Simic, Sonja; Maury, Stéphane; Delaunay, Alain; Joseph, Claude; Hagège, Daniel

2014-01-01

353

Effects of culture conditions on estrogen-mediated hepatic in vitro gene expression and correlation to in vivo responses  

International Nuclear Information System (INIS)

Refinement of in vitro systems for predictive toxicology is important in order to develop high-throughput early toxicity screening assays and to minimize animal testing studies. This study assesses the ability of mouse Hepa-1c1c7 hepatoma cell model under differing culture conditions to predict in vivo estrogen-induced hepatic gene expression changes. Custom mouse cDNA microarrays were used to compare Hepa-1c1c7 temporal gene expression profiles treated with 10 nM 17?-estradiol (E2) in serum-free and charcoal-stripped serum supplemented media at 1, 2, 4, 8, 12, and 24 h. Stripped serum supplemented media increased the number gene expression changes and overall responsiveness likely due to the presence of serum factors supporting proliferation and mitochondrial activity. Data from both experiments were compared to a gene expression time course study examining the hepatic effects of 100 ?g/kg 17?-ethynyl estradiol (EE) in C57BL/6 mice at 2, 4, 8, 12, 18, and 24 h. Only 18 genes overlapped between the serum-free and in vivo studies, whereas 238 genes were in common between Hepa-1c1c7 cells in stripped serum data and C57BL/6 liver samples. Stripped serum cultured cells exhibited E2-elicited gene expression changes associated with proliferation, cytoskeletal re-organization, cholesterol uptake and synthesis, increased fatty acid ?-oxidation, and oxidative stress, which correlated with in vivo hepatic responses. These results demonstrate that E2 treatment of Hepa-1c1c7 trate that E2 treatment of Hepa-1c1c7 cells in serum supplemented media modulate responses in selected pathways which appropriately model estrogen-elicited in vivo hepatic responses

354

Cultivate in vitro of wheat Anthers (Triticum Aestivum L.) In the ICA-TENZA and PAV -76 varieties  

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The objective of the present work consisted, in determining the cultivation conditions under which it was possible to induce through the technique of the cultivation of anthers, the callus formation and possible regeneration of green plants of wheat (Triticum aestivum L.) in the varieties ICA-Tenza and Pav -76. With the purpose of identifying the but appropriate state of development of the grain of pollen for the inoculation of the anthers, a cytologic study was made in which was correlation among the moriolic parameters of the plant; (inter liguler distances, auricle-knot distances and longitude of the edges) and the state of development of the microspore; Of the parameters, it was recommended to keep in mind the longitude from the edges when harvesting the experimental material. The anthers of both genotypes were inoculated in the means bases Pope 4 and N6, with hormonal levels of ELL (naftalen acetic acid) of 0.0, 0.5 and 1.0 mg/I. the answers of the genotypes were evaluated before the means of basal cultivation, in connection with the induction of tripes and the plants regeneration. Of the two used genotypes, the Pav -76 it presented bigger capacity to induce the formation of tripes, while the ICA-Tenza genotype presented a bigger answer capacity in the regeneration of plants so much green as albino. The results obtained allowed to establish that a relationship exists between the means of cultivation and the capacity of the genotypes to regenerate as much tripes ae genotypes to regenerate as much tripes as plants. Due to the drop survival of the regenerated plants, it was not possible to settle down with clarity a relationship of the ploidia level

355

Floral Transcriptomes in Woodland Strawberry Uncover Developing Receptacle and Anther Gene Networks.  

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Flowers are reproductive organs and precursors to fruits and seeds. While the basic tenets of the ABCE model of flower development are conserved in angiosperms, different flowering plants exhibit different and sometimes unique characteristics. A distinct feature of strawberry (Fragaria spp.) flowers is the development of several hundreds of individual apocarpous (unfused) carpels. These individual carpels are arranged in a spiral pattern on the subtending stem tip, the receptacle. Therefore, the receptacle is an integral part of the strawberry flower and is of significant agronomic importance, being the precursor to strawberry fruit. Taking advantage of next-generation sequencing and laser capture microdissection, we generated different tissue- and stage-transcriptomic profiling of woodland strawberry (Fragaria vesca) flower development. Using pairwise comparisons and weighted gene coexpression network analysis, we identified modules of coexpressed genes and hub genes of tissue-specific networks. Of particular importance is the discovery of a developing receptacle-specific module exhibiting similar molecular features to those of young floral meristems. The strawberry homologs of a number of meristem regulators, including LOST MERISTEM and WUSCHEL, are identified as hub genes operating in the developing receptacle network. Furthermore, almost 25% of the F-box genes in the genome are transiently induced in developing anthers at the meiosis stage, indicating active protein degradation. Together, this work provides important insights into the molecular networks underlying strawberry's unique reproductive developmental processes. This extensive floral transcriptome data set is publicly available and can be readily queried at the project Web site, serving as an important genomic resource for the plant biology research community. PMID:24828307

Hollender, Courtney A; Kang, Chunying; Darwish, Omar; Geretz, Aviva; Matthews, Benjamin F; Slovin, Janet; Alkharouf, Nadim; Liu, Zhongchi

2014-05-14

356

ECHIDNA protein impacts on male fertility in Arabidopsis by mediating trans-Golgi network secretory trafficking during anther and pollen development.  

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The trans-Golgi network (TGN) plays a central role in cellular secretion and has been implicated in sorting cargo destined for the plasma membrane. Previously, the Arabidopsis (Arabidopsis thaliana) echidna (ech) mutant was shown to exhibit a dwarf phenotype due to impaired cell expansion. However, ech also has a previously uncharacterized phenotype of reduced male fertility. This semisterility is due to decreased anther size and reduced amounts of pollen but also to decreased pollen viability, impaired anther opening, and pollen tube growth. An ECH translational fusion (ECHPro:ECH-yellow fluorescent protein) revealed developmentally regulated tissue-specific expression, with expression in the tapetum during early anther development and microspore release and subsequent expression in the pollen, pollen tube, and stylar tissues. Pollen viability and production, along with germination and pollen tube growth, were all impaired. The ech anther endothecium secondary wall thickening also appeared reduced and disorganized, resulting in incomplete anther opening. This did not appear to be due to anther secondary thickening regulatory genes but perhaps to altered secretion of wall materials through the TGN as a consequence of the absence of the ECH protein. ECH expression is critical for a variety of aspects of male reproduction, including the production of functional pollen grains, their effective release, germination, and tube formation. These stages of pollen development are fundamentally influenced by TGN trafficking of hormones and wall components. Overall, this suggests that the fertility defect is multifaceted, with the TGN trafficking playing a significant role in the process of both pollen formation and subsequent fertilization. PMID:24424320

Fan, Xinping; Yang, Caiyun; Klisch, Doris; Ferguson, Alison; Bhaellero, Rishi P; Niu, Xiwu; Wilson, Zoe A

2014-03-01

357

Hatching response to temperature along a latitudinal gradient by the fairy shrimp Branchinecta lindahli (Crustacea; Branchiopoda; Anostraca in culture conditions  

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Full Text Available Branchinecta lindahli is a broadly distributed fairy shrimp, reported from a range of temporary wetland habitat types in arid western North America. This species’ eggs hatch after the habitat dries, refills from seasonal rain, and receives a strong cold shock during the winter low temperatures. I studied phenotypic variation in temperature responses in cultures collected from four populations across 8° of latitude with low average temperatures ranging from -8 to 8°C. Time to maturation, mature body size and first clutch size decreased, as temperature increased, with only minor body size variability at mortality, regardless of culture origin. No variation in individual egg size was observed, demonstrating that body size is sacrificed to produce at least a few normal eggs during unfavourable years. Latitudinal variation in hatching temperature demonstrated a pattern of adaptive significance, with some overlap between regional temperature hatching cues.  Phenotypic hatching temperature and growth rate responses may cause genetic segregation, selecting one cohort for warmer, dryer years and one cohort for cooler, wetter years.  Drier year selected cohorts can exploit habitats that have shorter hydroperiods even in wet years. This may lead to population specialisation and speciation by adapting to more extreme habitats

D. Christopher Rogers

2014-02-01

358

Comparative study of proliferation of suckling and adult rat hepatocytes in primary culture in response to growth-stimulating factors.  

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Full Text Available The replicative responses of suckling and adult rat hepatocytes in primary culture to growth-stimulating factors were compared. By addition of L-proline alone, the [3H]-thymidine labeling of suckling rat hepatocytes was dramatically enhanced, but that of adult ones was not. Epidermal growth factor (EGF, insulin, triiodothyronine (T3 and glucagon also enhanced the labeling of suckling rat hepatocytes regardless of the presence or the absence of L-proline. On the other hand, in the absence of L-proline, only EGF enhanced the labeling of adult rat hepatocytes, and, in the presence of L-proline, insulin as well as EGF enhanced the labeling. In the presence of growth factors and L-proline, the number of suckling rat hepatocytes increased up to about 143%, whereas that of adult rat hepatocytes hardly increased. Thus, a remarkable difference in replicative responses to growth factors and L-proline was observed between suckling and adult rat hepatocytes in primary culture.

Handa,Yoshihiko

1986-12-01

359

Analyzing the metabolic stress response of recombinant Escherichia coli cultures expressing human interferon-beta in high cell density fed batch cultures using time course transcriptomic data.  

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Fed batch cultures expressing recombinant interferon beta under the T7 promoter were run with different exponential feeding rates of a complex substrate and induced at varying cell densities. Post-induction profiles of the specific product formation rates showed a strong dependence on the specific growth rate with the maximum product yield obtained at 0.2 h(-1). A study of the relative transcriptomic profiles as a function of pre-induction ? was therefore done to provide insight into the role of cellular physiology in enhancing recombinant protein expression. Hierarchical clustering analysis of the significantly regulated genes allowed us to identify biologically important groups of genes which fall under specific master regulators. The groups were: rpoH, ArcB, CreB, Lrp, RelA, Fis and Hfq. The response of these regulators, which exert a feedback control on the growth and product formation rates correlated well with the expression levels obtained. Thus at the optimum pre-induction ?, the alternative sigma factors and ribosomal machinery genes did not get depressed till the 6th hour post-induction unlike at other specific growth rates, demonstrating a critical role for the genes in sustaining recombinant protein expression. PMID:22134216

Singh, Anuradha B; Sharma, Ashish K; Mukherjee, Krishna J

2012-02-01

360

Modulation of cultured porcine granulosa cell responsiveness to follicle stimulating hormone and epidermal growth factor  

International Nuclear Information System (INIS)

Ovarian follicular development is dependent upon the coordinated growth and differentiation of the granulosa cells which line the follicle. Follicle stimulating hormone (FSH) induces granulosa cell differentiation both in vivo and in vitro. Epidermal growth factor (EGF) stimulates granulosa cell proliferation in vitro. The interaction of these two effectors upon selected parameters of growth and differentiation was examined in monolayer cultures of porcine granulose cells. Analysis of the EGF receptor by 125I-EGF binding revealed that the receptor was of high affinity with an apparent dissociation constant of 4-6 x 10-10 M. The average number of receptors per cell varied with the state of differentiation both in vivo and in vitro; highly differentiated cells bound two-fold less 125I-EGF and this effect was at least partially induced by FSH in vitro. EGF receptor function was examined by assessing EGF effects on cell number and 3H-thymidine incorporation. EGF stimulated thymidine incorporation in both serum-free and serum-supplemented culture, but only in serum-supplemented conditions was cell number increased. EGF receptor function was inversely related to the state of differentiation and was attenuated by FSH. The FSH receptor was examined by 125I-FSH binding. EGF increased FSH receptor number, and lowered the affinity of the receptor. The function of these receptors was assessed by 125I-hCG binding anassessed by 125I-hCG binding and progesterone radioimmunoassay. If EGF was present continuously in the cultures. FSH receptor function was attenuated regardless of FSH receptor number. A preliminary effort to examine the mechanism of this interaction was performed by analyzing hormonally controlled protein synthesis with 35S-methionine labeling, SDS polyacrylamide gel electrophoresis and fluorography. FSH promoted the expression of a 27,000 dalton protein. This effect was attenuated by EGF

 
 
 
 
361

Response of Bread Wheat Genotypes to Immature Embryo Culture, Callus Induction and Drought Stress  

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In order to evaluate the response of twenty genotypes of bread wheat (Triticum aestivum L.) to callus induction and in vitro drought stress. The immature embryos of wheat were used in a Completely Randomized Design (CRD) with six replications for callus induction and a 20×2 factorial experiment based on CRD design with three replications was carried out for response of genotypes to in vitro drought stress at the Agricultural College of Razi University, Kermanshah, Iran during 2010-2011. Sign...

Parvin Elyasi; Ezatollah Farshadfar; Mostafat Aghaee

2012-01-01

362

Comparative Tissue Culture Response of Wheat Cultivars and Evaluation of Regenerated Plants  

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Three wheat genotypes i.e. Bakhtawar-92, Punjab-96 and Inqilab-91 were tested for their response to callus induction frequency and their subsequent regeneration on a variety of media combinations. Bakhtawar-92 appeared to be the most responsive genotype to callus induction followed by Inqilab-91 and Punjab-96. It also produced significantly higher amount of callus as compared with other genotypes. However, the medium containing 2 mg l-1 2,4-D (2,4-dicholorophenoxy acetic acid) was ...

Muhammad Farooq; Hamid Rashid; Ihsanullah; Zubeda Chaudhry; Khan Bahadar Marwat

2004-01-01

363

Responses of neotropical mangrove seedlings grown in monoculture and mixed culture under treatments of hydroperiod and salinity  

Science.gov (United States)

We investigated the combined effects of salinity and hydroperiod on seedlings of Rhizophora mangle and Laguncularia racemosa grown under experimental conditions of monoculture and mixed culture by using a simulated tidal system. The objective was to test hypotheses relative to species interactions to either tidal or permanent flooding at salinities of 10 or 40 g/l. Four-month-old seedlings were experimentally manipulated under these environmental conditions in two types of species interactions: (1) seedlings of the same species were grown separately in containers from September 2000 to August 2001 to evaluate intraspecific response and (2) seedlings of each species were mixed in containers to evaluate interspecific, competitive responses from August 2002 to April 2003. Overall, L. racemosa was strongly sensitive to treatment combinations while R. mangle showed little effect. Most plant responses of L. racemosa were affected by both salinity and hydroperiod, with hydroperiod inducing more effects than salinity. Compared to R. mangle, L. racemosa in all treatment combinations had higher relative growth rate, leaf area ratio, specific leaf area, stem elongation, total length of branches, net primary production, and stem height. Rhizophora mangle had higher biomass allocation to roots. Species growth differentiation was more pronounced at low salinity, with few species differences at high salinity under permanent flooding. These results suggest that under low to mild stress by hydroperiod and salinity, L. racemosa exhibits responses that favor its competitive dominance over R. mangle. This advantage, however, is strongly reduced as stress from salinity and hydroperiod increase. ?? Springer 2006.

Cardona-Olarte, P.; Twilley, R.R.; Krauss, K.W.; Rivera-Monroy, V.

2006-01-01

364

Growth and enzymatic responses of phytopathogenic fungi to glucose in culture media and soil  

Directory of Open Access Journals (Sweden)

Full Text Available The effect of inoculation of Aspergillus flavus, Fusarium verticillioides, and Penicillium sp. in Dystrophic Red Latosol (DRL and Eutroferric Red Latosol (ERL soils with or without glucose on the total carbohydrate content and the dehydrogenase and amylase activities was studied. The fungal growth and spore production in culture medium with and without glucose were also evaluated. A completely randomized design with factorial arrangement was used. The addition of glucose in the culture medium increased the growth rate of A. flavus and Penicillium sp. but not of F. verticillioides. The number of spores increased 1.2 for F. verticillioides and 8.2 times for A. flavus in the medium with glucose, but was reduced 3.5 times for Penicillium sp. The total carbohydrates contents reduced significantly according to first and second degree equations. The consumption of total carbohydrates by A. flavus and Penicillium sp. was higher than the control or soil inoculated with F. verticillioides. The addition of glucose to soils benefited the use of carbohydrates, probably due to the stimulation of fungal growth. Dehydrogenase activity increased between 1.5 to 1.8 times (p <0.05 in soils with glucose and inoculated with the fungi (except F. verticillioides, in relation to soil without glucose. Amylase activity increased 1.3 to 1.5 times due to the addition of glucose in the soil. Increased amylase activity was observed in the DRL soil with glucose and inoculated with A. flavus and Penicillium sp. when compared to control.

Beatriz de Oliveira Costa

2012-03-01

365

Rice improvement, involving altered flower structure more suitable to cross-pollination, using in vitro culture in combination with mutagenesis  

International Nuclear Information System (INIS)

Anther and somatic tissue culture in combination with mutagenesis were carried out to evaluate the efficiency of different mutagenic treatments of various in vitro culture materials, and to obtain some promising variants for rice improvement. Results indicated that in japonica rice radiation treatment of dry seeds and young panicles influenced the percentage of green plantlets regeneration from anther culture. Both treatments increased significantly the percentage of regenerated green plantlets in comparison with the control. Irradiation with 30 Gy of rice callus increased also the percentage of regenerated green plantlets. For indica rice, the combination of the suitable dose of gamma rays irradiation on seeds and an improved medium, increased the percentage of callus induction. This approach made it possible to use anther culture in indica rice breeding. Somatic tissue cultures combined with radiation-induced mutagenesis led to the development of a number of promising mutants including some new cytoplasm-nucleus interacting male-sterile lines with almost 100% stigma exertion. Their development would be of practical significance for increasing the genetic diversity for production of hybrid rice. (author)

366

Educational Leadership in the Age of Diversity: A Case Study of Middle School Principals' Cultural Awareness and Influence in Relation to Teachers' Cultural Awareness and the Use of Culturally Responsive Curriculum and Pedagogy in Classrooms  

Science.gov (United States)

This embedded case study examined middle school principals' self-reported cultural awareness, teachers' self-reported cultural awareness, and principals' influence on cultural awareness in the school. In addition, the study focused on how principals influenced teachers' cultural awareness and implementation of multicultural education, and…

Robinson, Lynda Marie Cesare

2010-01-01

367

Safety culture  

International Nuclear Information System (INIS)

The response to a previous publication by the International Nuclear Safety Advisory Group (INSAG), indicated a broad international interest in expansion of the concept of Safety Culture, in such a way that its effectiveness in particular cases may be judged. This report responds to that need. In its manifestation, Safety Culture has two major components: the framework determined by organizational policy and by managerial action, and the response of individuals in working within and benefiting by the framework. 1 fig

368

Safety culture  

International Nuclear Information System (INIS)

The response to a previous publication by the International Nuclear Safety Advisory Group (INSAG) indicated a broad international interest in expanding the concept of Safety Culture in such a way that its effectiveness in particular cases may be judged. This report responds to that need. In its manifestation, Safety Culture has two major components: the framework determined by organizational policy and by managerial action, and the response of individuals in working within and benefiting by the framework. 1 fig

369

Sociocultural factors of teenage pregnancy in Latino communities: preparing social workers for culturally responsive practice.  

Science.gov (United States)

Despite gains in reducing teenage pregnancy during the past 20 years, disparities in teenage pregnancy rates persist: The teenage pregnancy rate in Latino communities is now nearly double the average rate of teenage pregnancy in the United States. Considering the significant risks teenage pregnancy and parenting pose to both the teenager and the child, and that social workers are already often working in communities with populations at risk, this is not only a major public health issue, but one that the field of social work is well positioned to actively address. This article synthesizes pertinent literature on some of the social and cultural influences important for understanding this phenomenon. Implications for social work practice are discussed. PMID:25369724

Aparicio, Elizabeth; Pecukonis, Edward V; Zhou, Kelly

2014-11-01

370

Response of Grape Explants (cv. Bidaneh Soltani to Different Culture Media  

Directory of Open Access Journals (Sweden)

Full Text Available To study the effects of different combinations of auxin (IBA, NAA and cytokinin (BAP, TDZ regulators, basal salts (MS, WPM, NN and gelling agents (Gelrite and Plant Agar on the growth and development of seedless grape explants (cv. Bidaneh Soltani, a factorial experiment was conducted based on a completely randomized design. The number and length of grown shoots were analyzed as two main characteristics. Growth regulators and salts had significant effects (at %1 on the shoot proliferation. The highest number of shoots was observed on MS salts combined with BAP (2.2 mg/l and IBA (0.5 mg/l on the 18th days of culture. Compared to Plant Agar, Gelrite had a better effect on the normal growth of the shoots. Based on the new shoots, combinations of MS salts and hormones may be used for micropropagation of seedless grape cultivars in the in vitro condition.

GH. Garousi

2008-10-01

371

Science in Hawaii/Haawina Hoopapau: A Culturally Responsive Curriculum Project  

Science.gov (United States)

The marvels of modern science often fail to engage indigenous students, as the content and instructional style are usually rooted in the Western experience. This 3 year project, funded by the US Dept. of Education for the Education of Native Hawaiians, offers a curriculum that teaches science through (rather than just about) Native Hawaiian culture. The curriculum focuses on the interdependence of natural resources in our ahupuaa, or watersheds, and helps students strengthen their sense of place and self to malama i ka aina, to care for the land. Further, the curriculum is designed to: engage students in scientific study with relevant, interesting content and activities; improve student achievement of state department of education standards; increase student knowledge and skills in science, math and language arts; respond to the learning needs of Native Hawaiian and/or at-risk students. The project will be presented by a curriculum writer who created and adapted more than a year's worth of materials by teaming with kupuna (respected elders), local cultural experts and role models, educators (new, veteran, Hawaiian, non-Hawaiian, mainland, general and special education teachers), and professionals at the Center on Disability Studies at the University of Hawaii and ALU LIKE, Inc, a non-profit organization to assist Native Hawaiians. The materials created thus far are available for viewing at: www.scihi.hawaii.edu The curriculum, designed for grades 8-11 science classes, can be used to teach a year-long course, a unit, or single lesson related to astronomy, biology, botany, chemistry, geology, oceanography, physical and environmental sciences. This project is in its final year of field testing, polishing and dissemination, and therefore this session will encourage idea sharing, as does our copyright free Web site.

Galloway, L. M.; Roberts, K.; Leake, D. W.; Stodden, R. S.; Crabbe, V.

2005-12-01

372

Cultural Transferability of Socially Responsible Leadership: Findings from the United States and Mexico  

Science.gov (United States)

The purpose of this study was to examine similarities and differences in students' capacities for socially responsible leadership as well as significant predictors of its development at a higher education institution in Mexico as compared with US schools. Results revealed that Mexican students both entered and left college with significantly…

Dugan, John P.; Rossetti Morosini, Ana M.; Beazley, Michael R.

2011-01-01

373

Probiotics cultures in animal feed: Effects on ruminal fermentation, immune responses, and resistance to infectious diseases  

Science.gov (United States)

We evaluated the effects of probiotics included in dairy cattle and mice feed on ruminal fermentation, immune responses, and resistance to Johne’s disease. To unveil the underlying mechanisms, dairy cattle were either fed Bovamine (1.04 x 10**9 cfu of Lactobacillus acidophilus NP51 plus 2.04 x 10**...

374

Molecular analysis of chondrocytes cultured in agarose in response to dynamic compression  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background Articular cartilage is exposed to high mechanical loads under normal physiological conditions and articular chondrocytes regulate the composition of cartilaginous matrix, in response to mechanical signals. However, the intracellular pathways involved in mechanotransduction are still being defined. Using the well-characterized chondrocyte/agarose model system and dynamic compression, we report protocols for preparing and characterizing constructs of murine ...

Mallein-Gerin Frédéric; Aubert-Foucher Elisabeth; Paumier Anne; Bougault Carole

2008-01-01

375

Maximized virulence in a sterilizing pathogen: the anther-smut fungus and its co-evolved hosts.  

Science.gov (United States)

Host sterilization is a common feature of sexually transmitted diseases (STDs). Because host reproductive failure may free up resources for pathogen reproduction and transmission, theory predicts that selection on sterilizing pathogens will favour maximum virulence (i.e. complete sterilization). We examined patterns of infection in sexually transmitted anther-smut fungi (Microbotryum) on four of their host species in the Caryophyllaceae. Using controlled fungal matings and experimental inoculations, we compared disease expression in inoculations ranging from host-specific pathogens to hybrids and cross-species treatments. Our data support the existence of host-specific sibling species within the genus Microbotryum based on a low infection rate from cross-inoculations and reduced fitness for hybrid pathogens. These patterns of host specificity and reproductive isolation, however, were not absolute. We did observe some successful cross-species and hybrid infections, but the expression of disease was frequently incomplete, including only partial host sterilization and the failed dehiscence of pathogen spores. The prevalence of these maladapted disease phenotypes may greatly inhibit the emergence of novel host pathogen combinations. Infections by hybrid pathogen genotypes were intermediate, in terms of both infection rate and the normality of disease symptoms, between host-specific and cross-inoculated pathogens. In addition, the frequency with which hybrid and cross-inoculated anther-smut pathogens were able to infect but not sterilize new hosts supports the prediction that sterilizing STDs are under selection to maximize virulence in natural populations. PMID:18717748

Sloan, D B; Giraud, T; Hood, M E

2008-11-01

376

Temporal and spatial distribution of pectin epitopes in differentiating anthers and microspores of fertile and sterile sugar beet.  

Science.gov (United States)

We studied the possible involvement of several pectin epitopes in anther differentiation and microsporogenesis in fertile and cytoplasmically male sterile sugar beets. The spatial and temporal distribution of five structural motifs were traced with a panel of monoclonal antibodies in six stages: premeiosis, meiotic prophase, young and mature tetrads, young and expanding microspores. The composition of the walls of sporogenous cells and meiocytes differed than that in the tapetum, as evidenced by the presence of alpha-Fuc(1-->2)-beta-Gal and alpha-(1-->5)-L-Ara epitopes binding CCRC-M1 and LM6 antibodies. At meiotic prophase, the meiocyte walls were additionally marked by the appearance of poorly methyl-esterified domains of homogalacturonan and of (1-->4)-beta-Gal residues, detected by JIM5 and LM5. Some constituents of the meiocyte wall which reacted with JIM5 and JIM7 persisted on the surface of the special callose sheath during tetrad development. In newly formed primexine and exine layers of tetrads and microspores, epitopes that were bound by JIM5, JIM7 and LM5 were abundant. No differences in the deposition or relative abundance of pectins were found between fertile and sterile anthers until microspore release from the callose. Later, at the time of abortion, sterile microspores had much larger amounts of epitopes detected by JIM5 than their fertile counterparts. PMID:15169938

Majewska-Sawka, Anna; Münster, Agnieszka; Wisniewska, Ewa

2004-05-01

377

Reflexiones sobre la actualidad del relativismo cultural: respuesta a Nicolás Sánchez Durá / Considerations about the Pertinence of Cultural Relativism: Response to Nicolás Sánchez Durá  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish Este ensayo propone entablar una discusión con las tesis contenidas en el artículo de Nicolás Sánchez Durá, "Actualidad del relativismo cultural". En primer lugar, se analizan el etnocentrismo y el relativismo como dos respuestas éticas distintas al fenómeno de la diversidad cultural. En segundo lug [...] ar, se desarrollan la formulación del relativismo y el concepto de cultura propuestos por Sánchez Durá para analizarlos a la luz de la epistemología elaborada por el Wittgenstein tardío. En tercer lugar, se agregan argumentos a favor del relativismo cultural. El relativismo cultural, visto como una doctrina, tropieza con dilemas lógicos y conceptuales; considerado como una actitud contextual de índole moral y política, contribuye a combatir la autoridad del etnocentrismo basado en la exclusividad del otro. Abstract in english This essay proposes to develop and to discuss some thesis included in the article by Nicolás Sánchez Durá: "The Pertinence of Cultural Relativism". Firstly, the ethnocentric and relativistic positions are both considered as two different ethical attitudes towards the cultural diversity. Secondly, th [...] e concepts of "relativism" and "culture" are developed and analyzed in the light of Ludwig Wittgenstein's later philosophy. Although, the cultural relativism considered as a philosophical doctrine faces logical and conceptual dilemmas, the latter disappear when relativism is treated as contextual, mostly moral and political attitude, which contributes to undermine the legacy of ethno-centrism based on the other's exclusivity.

Witold, Jacorzynski.

2013-04-01

378

Reactive oxygen and nitrogen species in defense/stress responses activated by chitosan in sycamore cultured cells.  

Science.gov (United States)

Chitosan (CHT) is a non-toxic and inexpensive compound obtained by deacetylation of chitin, the main component of the exoskeleton of arthropods as well as of the cell walls of many fungi. In agriculture CHT is used to control numerous diseases on various horticultural commodities but, although different mechanisms have been proposed, the exact mode of action of CHT is still unknown. In sycamore (Acer pseudoplatanus L.) cultured cells, CHT induces a set of defense/stress responses that includes production of H2O2 and nitric oxide (NO). We investigated the possible signaling role of these reactive molecules in some CHT-induced responses by means of inhibitors of production and/or scavengers. The results show that both reactive nitrogen and oxygen species are not only a mere symptom of stress conditions but are involved in the responses induced by CHT in sycamore cells. In particular, NO appears to be involved in a cell death form induced by CHT that shows apoptotic features like DNA fragmentation, increase in caspase-3-like activity and release of cytochrome c from the mitochondrion. On the contrary, reactive oxygen species (ROS) appear involved in a cell death form induced by CHT that does not show these apoptotic features but presents increase in lipid peroxidation. PMID:25642757

Malerba, Massimo; Cerana, Raffaella

2015-01-01

379

Cellular responses in primary epidermal cultures from oncorhynchus mykiss following the combined exposure of ionising radiation and a heavy metal  

International Nuclear Information System (INIS)

Mechanisms of toxicant action on biological systems are difficult to identify when more than one contaminant is involved due to potential synergistic and antagonistic effects. There is a general paucity of research into the effect of radiation exposure in tandem with common environmental contaminants due to the inherent difficulties involved. In vitro cell cultures are particularly suited to the study of toxic mechanisms due to their proximity to toxic modes of action and the absence of the multiple defence mechanisms present in intact organisms. Primary cell cultures are particularly beneficial in this area of research as they still maintain many of their tissue specific functions. The objective of this study was to distinguish different mechanisms of cell death (growth arrest, apoptosis, primary and secondary necrosis and proliferation), following combination exposure to ionising radiation and a heavy metal (ZnCl2). The model system employed was a primary cell culture of rainbow trout (Oncorhynchus mykiss) epidermal tissue which has been previously used to study the effects of various environmental agents in this laboratory. Apoptosis and necrosis were quantified morphologically while proliferation was assessed immuno-cyto-chemically using an anti PCNA (proliferating cell nuclear antigen) antibody. While radiation doses up to and including 10 Gy had no effect on growth, exposure to ZnCl2 produced a significant dose dependent reduction in growth (10, 50, 75, 100 and 200 ppm ZnCl2). Preliminary results indicate no significant effect on growth following a combined exposure of 5 Gy + 50 ppm ZnCl2. These results may have important implications for understanding the mechanisms underlying cellular responses to multiple contaminant exposures. (author)

380

Differences in the response of UCP1 mRNA to hormonal stimulation between rat and mouse primary cultures of brown adipocytes  

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Uncoupling protein 1 (UCP-1), the specific marker of brown adipose tissue, is transcriptionally activated in response to adrenergic stimuli and thyroid hormones are necessary for its full expression. We describe differences in the regulation of UCP-1 mRNA expression between rat and mouse brown adipocytes in culture, using norepinephrine (NE), triiodothyronine (T3), insulin and retinoic acid (RA). Results: NE and cAMP-elevating agents strongly increase UCP-1 mRNA levels in cultures of mouse ad...

Herna?ndez, Arturo; Marti?nez Mena, Raquel; Martin, Eva; Orego?n, Mari?a Jesu?s

2011-01-01

 
 
 
 
381

Correlation of Cellular Immune Responses with Protection against Culture-Confirmed Influenza Virus in Young Children?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The highly sensitive gamma interferon (IFN-?) enzyme-linked immunosorbent spot (ELISPOT) assay permits the investigation of the role of cell-mediated immunity (CMI) in the protection of young children against influenza. Preliminary studies of young children confirmed that the IFN-? ELISPOT assay was a more sensitive measure of influenza memory immune responses than serum antibody and that among seronegative children aged 6 to <36 months, an intranasal dose of 107 fluorescent focus units (FF...

Forrest, Bruce D.; Pride, Michael W.; Dunning, Andrew J.; Capeding, Maria Rosario Z.; Chotpitayasunondh, Tawee; Tam, John S.; Rappaport, Ruth; Eldridge, John H.; Gruber, William C.

2008-01-01

382

Bacterial growth and substrate degradation by BTX-oxidizing culture in response to salt stress.  

Science.gov (United States)

Interactions between microbial growth and substrate degradation are important in determining the performance of trickle-bed bioreactors (TBB), especially when salt is added to reduce biomass formation in order to alleviate media clogging. This study was aimed at quantifying salinity effects on bacterial growth and substrate degradation, and at acquiring kinetic information in order to improve the design and operation of TBB. Experiment works began by cultivating a mixed culture in a chemostat reactor receiving artificial influent containing a mixture of benzene, toluene, and xylene (BTX), followed by using the enrichment culture to degrade the individual BTX substrates under a particular salinity, which ranged 0-50 g l(-1) in batch mode. Then, the measured concentrations of biomass and residual substrate versus time were analyzed with the microbial kinetics; moreover, the obtained microbial kinetic constants under various salinities were modeled using noncompetitive inhibition kinetics. For the three substrates the observed bacterial yields appeared to be decreased from 0.51-0.74 to 0.20-0.22 mg mg(-1) and the maximum specific rate of substrate utilization, q, declined from 0.25-0.42 to 0.07-0.11 h(-1), as the salinity increased from 0 to 50 NaCl g l(-1). The NaCl acted as noncompetitive inhibitor, where the modeling inhibitions of the coefficients, K ( T(S)), were 22.7-29.7 g l(-1) for substrate degradation and K ( T(mu)), 13.0-19.0 g l(-1), for biomass formation. The calculated ratios for the bacterial maintenance rate, m (S), to q, further indicated that the percentage energy spent on maintenance increased from 19-24 to 86-91% as salinity level increased from 0 to 50 g l(-1). These results revealed that the bacterial growth was more inhibited than substrate degradation by the BTX oxidizers under the tested salinity levels. The findings from this study demonstrate the potential of applying NaCl salt to control excessive biomass formation in biotrickling filters. PMID:16284744

Lee, Chi-Yuan; Lin, Ching-Hsing

2006-01-01

383

Response of Bread Wheat Genotypes to Immature Embryo Culture, Callus Induction and Drought Stress  

Directory of Open Access Journals (Sweden)

Full Text Available In order to evaluate the response of twenty genotypes of bread wheat (Triticum aestivum L. to callus induction and in vitro drought stress. The immature embryos of wheat were used in a Completely Randomized Design (CRD with six replications for callus induction and a 20×2 factorial experiment based on CRD design with three replications was carried out for response of genotypes to in vitro drought stress at the Agricultural College of Razi University, Kermanshah, Iran during 2010-2011. Significant differences were observed among the genotypes for Callus Growth Rate (CGR, Relative Fresh Weight Growth (RFWG, Relative Growth Rate (RGR and Percentage of Callus Induction (PCI indicating the presence of genetic variability, different responses of bread wheat genotypes to callus induction and possible selection of callus induction at in vitro level using immature embryos. Mean comparison of the traits measured in callus induction showed that genotypes 1 and 6 had the highest PCI (100%. Analysis of variance for CGR, RFWG and RGR, Relative Water Content (RWC, Percent of Callus Chlorosis (PCC and Proline Content (PC exhibited significant differences among the genotypes for all the characters in the stress condition (15% PEG. Screening drought tolerant genotypes and in vitro indicators of drought tolerance using mean rank, standard deviation of ranks and biplot analysis, discriminated genotypes (6, (19 and (1 as the most drought tolerant.

Parvin Elyasi

2012-07-01

384

Putting NIMBY in perspective: The cultural origins of public response to hazardous waste  

International Nuclear Information System (INIS)

The study of public response to the siting of hazardous waste treatment facilities has found a natural home in the literature on localized reaction, the so-called NIMBY (not in my backyard) syndrome. This concern for dealing with NIMBY in practical terms has fallen short in two respects. First, NIMBY has become isolated from two other basic responses: generalized acceptance (open-quotes Yes, in my backyardclose quotes or YIMBY) and generated opposition (open-quotes Not in anybody's backyardclose quotes or NAMBY). Second, too narrow a focus on NIMBY neglects a potentially revealing explanatory analogy: the parallel between the controversy over hazardous waste facilities and other technical controversies, such as the decades-old debate over nuclear power. In this paper, we review three theories that have been developed to explain general attitudes toward risk-bearing technologies. Using data from a statewide random sample, we then look to see if variables that figure prominently in these theories help shape the NIMBY, YIMBY or NAMBY responses to hazardous waste facilities

385

The university as an encounter for deliberative communication - creating cultural citizenship and professional responsibility  

Directory of Open Access Journals (Sweden)

Full Text Available How can higher and professional education contribute to the development of responsible citizenship and professional responsibility? In recent discussions on the role of the educational system, the idea of “deliberative communication” has been brought into focus and stands for communication in which different opinions and values can be set against each other in educational settings. It implies an endeavour by each individual to develop his or her view by listening, deliberating, seeking arguments and valuing, coupled to a collective and cooperative endeavour to find values and norms which everyone can accept, at the same time as pluralism is acknowledged. Within higher education deliberative communication might explicitly be used to develop professional responsibility and analysing consequences of different ways of solving problems. To what extent are and can universities become public spaces for encounters dealing with controversial questions of how to solve different problems and analyse different ways of professional acting? Can universities recreate their selective traditions, “institutionalize dissensus”, and “make the university a site of public debate” through deliberative communication?

Tomas Englund

2008-01-01

386

Tissue Culture response of Local Varieties of Rice (Oryza sativa L. of NWFP  

Directory of Open Access Journals (Sweden)

Full Text Available Four rice genotypes i.e. Swat I, Swat II, Dilrosh 97 and Pakhal were tested for their callus induction frequency and their subsequent regeneration from different explants on a variety of media combinations. Swat I appeared to be the most responsive genotype to callus induction followed by Swat II, Dilrosh 97 and Pakhal respectively. Swat I and Swat II produced high amount of callus compared to other genotypes. Callus induction frequencies ranged from 68.88 to 57.70 percent in Swat I, 60.00 percent in Swat II, 52.20 percent in Dilrosh 97 and 40.00 to 42.20 percent in Pakhal from scutella on two different media. Similar response was also found for root induced calli. However, N6 medium containing 2 mg/l of 2,4-D was found to be optimum for callus induction irrespective of the genotypes and explant studied. All varieties showed significant differences in regeneration from two and three week old calli. RM medium containing MS salts and vitamins, 2 gm casamino acid, 1 mg/l NAA, 2 mg/l BAP and 30 gm sorbitol gave comparatively higher regeneration response than the other two media tested. Plants regenerated were grown in harmone free MS medium for vigorous rooting and subsequent transfer to soil.

Asad Jan

2001-01-01

387

Growth Characteristics Modeling of Mixed Culture of Bifidobacterium bifidum and Lactobacillus acidophilus using Response Surface Methodology and Artificial Neural Network  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Different culture conditions viz. additional carbon and nitrogen content, inoculum size and age, temperature and pH of the mixed culture of Bifidobacterium bifidum and Lactobacillus acidophilus were optimized using response surface methodology (RSM) and artificial neural network (ANN). Kinetic growt [...] h models were fitted for the cultivations using a Fractional Factorial (FF) design experiments for different variables. This novel concept of combining the optimization and modeling presented different optimal conditions for the mixture of B. bifidum and L. acidophilus growth from their one variable at-a-time (OVAT) optimization study. Through these statistical tools, the product yield (cell mass) of the mixture of B. bifidum and L. acidophilus was increased. Regression coefficients (R2) of both the statistical tools predicted that ANN was better than RSM and the regression equation was solved with the help of genetic algorithms (GA). The normalized percentage mean squared error obtained from the ANN and RSM models were 0.08 and 0.3%, respectively. The optimum conditions for the maximum biomass yield were at temperature 38°C, pH 6.5, inoculum volume 1.60 mL, inoculum age 30 h, carbon content 42.31% (w/v), and nitrogen content 14.20% (w/v). The results demonstrated a higher prediction accuracy of ANN compared to RSM.

Ganga Sahay, Meena; Gautam Chandra, Majumdar; Rintu, Banerjee; Nitin, Kumar; Pankaj Kumar, Meena.

2014-12-01

388

Adaptation of anaerobic cultures of Escherichia coli K-12 in response to environmental trimethylamine-N-oxide.  

Science.gov (United States)

Systematic analyses of transcriptional and metabolic changes occurring when Escherichia coli K-12 switches from fermentative growth to anaerobic respiratory growth with trimethylamine-N-oxide (TMAO) as the terminal electron acceptor revealed: (i) the induction of torCAD, but not genes encoding alternative TMAO reductases; (ii) transient expression of frmRAB, encoding formaldehyde dehydrogenase; (iii) down-regulation of copper-resistance genes. Simultaneous inference of 167 transcription factor (TF) activities implied that transcriptional reprogramming was mediated by 20 TFs, including the transient inactivation of the two-component system ArcBA; a prediction validated by direct measurement of phosphorylated ArcA. Induction of frmRAB, detection of dimethylamine in culture medium and formaldehyde production when cell-free extracts were incubated with TMAO suggested the presence of TMAO demethylase activity. Accordingly, the viability of an frmRAB mutant was compromised upon exposure to TMAO. Down-regulation of genes involved in copper-resistance could be accounted for by TMAO inhibition of Cu(II) reduction. The simplest interpretation of the data is that during adaptation to the presence of environmental TMAO, anaerobic fermentative cultures of E. coli respond by activating the TorTSR regulatory system with consequent induction of TMAO reductase activity, resulting in net oxidation of menaquinone and inhibition of Cu(II) reduction, responses which are sensed by ArcBA and CusRS, respectively. PMID:25471524

Denby, Katie J; Rolfe, Matthew D; Crick, Ellen; Sanguinetti, Guido; Poole, Robert K; Green, Jeffrey

2014-12-01

389

Low level of O2 inhibits commitment of cultured mesenchymal stromal precursor cells from the adipose tissue in response to osteogenic stimuli.  

Science.gov (United States)

Mesenchymal stromal precursor cells from human lipoaspirate (lMSC) cultured at 5% O(2) formed 50% less mineralized matrix in response to osteogenic induction than cells cultured under standard conditions (20% O(2)). After lMSC percultured at 5% O(2) were transferred to normoxic conditions (20% O(2)), they produced the same amount of matrix as lMSC permanently cultured at 20% O(2). Hence, hypoxia inhibited the commitment of lMSC under the effect of osteogenic stimuli, which can be important in reparative and regenerative medicine. PMID:19902077

Grinakovskaya, O S; Andreeva, E R; Buravkova, L B; Rylova, Yu V; Kosovsky, G Yu

2009-06-01

390

Understanding the Way Students Speak: A Guide for Educators on Creating Culturally Responsive Environments for Linguistically Diverse Students  

Directory of Open Access Journals (Sweden)

Full Text Available Dialectal diversity is an area of student diversity that is often overlooked in terms of how educators view students who speak nonstandard forms of English. Moreover, public school educators must explore the issue of dialectal diversity among students and how they are perceived based on their language variation. More importantly, educators must examine their perceptions about those who speak non Standard English and how their perceptions translate into classroom practices. This is a theoretical article that explores students’ language variations and its impact on their educational opportunities. More importantly, it examines the notion of teacher perceptions of students who speak nonstandard variations of Standard English and their classroom practices. The article explores the relationship between dialectal diversity and student achievements as well as the role of educators have in creating culturally responsive educational environments to maximize students’ potential. The article also provides guidelines for educators on how to create an optimum learning environment for students.

Alisa Taliaferro

2012-07-01

391

Elicitor stimulation of the defense response in cultured plant cells monitored by fluorescent dyes.  

Science.gov (United States)

Addition of fungal elicitors to plant cells in suspension is known to stimulate biochemical changes in the plant cell leading to production of defense compounds. In this paper we demonstrate that introduction of elicitors from the pathogenic fungus Verticillium dahliae to cultured cotton, tobacco, or soybean cells leads to a rapid, dramatic change in the fluorescence of several membrane-associated potentiometric or pH-sensitive dyes. The fluorescence transitions occur abruptly following a brief (0 to 10 min) lag period in apparently most cells of the suspension simultaneously. Furthermore, both the length of the lag period and the rate of the subsequent fluorescence change were shown to be highly dependent on elicitor concentration. When the crude elicitor extract was separated by gel filtration chromatography into several active fractions, the ability of each fraction to stimulate phytoalexin production in the cotton cell suspension was found to correlate directly with the rate of the fluorescence decrease in the fluorescence assay. Because the assay is rapid, simple to perform, quantitative, and reproducible, it represents an attractive alternative to the more cumbersome and perhaps less quantitative elicitor assays currently in use. The fact that membrane-potential-sensitive dyes of different structure respond to elicitation of plant cells similarly further suggests, but does not prove, that asymmetric ion fluxes into or out of the plant cell are involved in the initial events of elicitor signal transduction. PMID:3753013

Low, P S; Heinstein, P F

1986-09-01

392

Investigation of magnesium-zinc-calcium alloys and bone marrow derived mesenchymal stem cell response in direct culture.  

Science.gov (United States)

Crystalline Mg-Zn-Ca ternary alloys have recently attracted significant interest for biomedical implant applications due to their promising biocompatibility, bioactivity, biodegradability and mechanical properties. The objective of this study was to characterize as-cast Mg-xZn-0.5Ca (x=0.5, 1.0, 2.0, 4.0wt.%) alloys, and determine the adhesion and morphology of bone marrow derived mesenchymal stem cells (BMSCs) at the interface with the Mg-xZn-0.5Ca alloys. The direct culture method (i.e. seeding cells directly onto the surface of the sample) was established in this study to probe the highly dynamic cell-substrate interface and thus to elucidate the mechanisms of BMSC responses to dynamic alloy degradation. The results showed that the BMSC adhesion density on these alloys was similar to the cell-only positive control and the BMSC morphology appeared more anisotropic on the rapidly degrading alloy surfaces in comparison with the cell-only positive control. Importantly, neither culture media supplemented with up to 27.6mM Mg(2+) ions nor media intentionally adjusted up to alkaline pH 9 induced any detectable adverse effects on BMSC responses. We speculated that degradation-induced dynamic surface topography played an important role in modulating cell morphology at the interface. This study presents a clinically relevant in vitro model for screening bioresorbable alloys, and provides useful design guidelines for determining the degradation rate of implants made of Mg-Zn-Ca alloys. PMID:25449917

Cipriano, Aaron F; Sallee, Amy; Guan, Ren-Guo; Zhao, Zhan-Yong; Tayoba, Myla; Sanchez, Jorge; Liu, Huinan

2015-01-15

393

Investigation of adaptive responses in bystander cells in 3D cultures containing tritium-labeled and unlabeled normal human fibroblasts.  

Science.gov (United States)

The study of radiation-induced bystander effects in normal human cells maintained in three-dimensional (3D) architecture provides more in vivo-like conditions and is relevant to human risk assessment. Linear energy transfer, dose and dose rate have been considered as critical factors in propagating radiation-induced effects. This investigation uses an in vitro 3D tissue culture model in which normal AG1522 human fibroblasts are grown in a carbon scaffold to investigate induction of a G(1) arrest in bystander cells that neighbor radiolabeled cells. Cell cultures were co-pulse-labeled with [(3)H]deoxycytidine ((3)HdC) to selectively irradiate a minor fraction of cells with 1-5 keV/microm beta particles and bromodeoxyuridine (BrdU) to identify the radiolabeled cells using immunofluorescence. The induction of a G(1) arrest was measured specifically in unlabeled cells (i.e. bystander cells) using a flow cytometry-based version of the cumulative labeling index assay. To investigate the relationship between bystander effects and adaptive responses, cells were challenged with an acute 4 Gy gamma-radiation dose after they had been kept under the bystander conditions described above for several hours, and the regulation of the radiation-induced G(1) arrest was measured selectively in bystander cells. When the average dose rate in (3)HdC-labeled cells (dose 0.14-10 Gy), no statistically significant stressful bystander effects or adaptive bystander effects were observed as measured by magnitude of the G(1) arrest, micronucleus formation, or changes in mitochondrial membrane potential. Higher dose rates and/or higher LET may be required to observe stressful bystander effects in this experimental system, whereas lower dose rates and challenge doses may be required to detect adaptive bystander responses. PMID:20681788

Pinto, Massimo; Azzam, Edouard I; Howell, Roger W

2010-08-01

394

Transformation and analysis of tobacco plant var Petit havana with T-urf13 gene under anther-specific TA29 promoter.  

Science.gov (United States)

T-urf13, a well-documented cms-associated gene from maize, has been shown to render methomyl sensitivity to heterologous systems like rice, yeast and bacteria when expressed constitutively. Since these transgenic plants were fertile, it was hypothesized that T-urf13 gene if expressed in anthers may result in male sterility that could be used for hybrid seed production. Hence, this work was aimed at analysing whether T-urf13 gene when expressed in anthers can result in male sterile plants or requires methomyl treatment to cause male sterility (controllable). This is the first report of transformation of tobacco with T-urf13 gene under anther-specific promoter (TA29) with or without mitochondrial targeting sequence. Most of the transgenic plants obtained were fertile; this was surprising as many male sterile plants were expected as T-urf13 gene is a cms associated gene. Our results suggest that it may not be possible to obtain male sterility by expressing URF13 in the anther by itself or by methomyl application. PMID:22582148

Arun, V; Kuriakose, Boney; Sridhar, Vaniyambadi V; Thomas, George

2011-09-01

395