Sample records for prolific shoot regeneration

  1. Adventitious shoots induction and plant regeneration from ...



    Jul 8, 2015 ... vitro plant regeneration for three watermelon cultivars. To achieve optimal .... watermelon genotypes gave shoot differentiation fre- quencies of 8.33-83.33% on MB5 .... They thought cells competent for shoot formation are not ...

  2. Prolific plant regeneration from protoplast-derived tissues of Lotus corniculatus L. (birdsfoot trefoil).

    Ahuja, P S; Hadiuzzaman, S; Davey, M R; Cocking, E C


    Protoplasts isolated enzymatically from seedling roots, hypocotyls and cotyledons of Lotus corniculatus L. produced callus which underwent prolific shoot regeneration. The rapidity and ease of recovering plants from protoplast-derived tissues makes this forage legume an attractive experimental system for genetic manipulation.

  3. Light Requirement for Shoot Regeneration in Horseradish Hairy Roots 1

    Saitou, Tsutomu; Kamada, Hiroshi; Harada, Hiroshi


    Hairy roots of horseradish (Armoracia rusticana) were induced by inoculation with Agrobacterium rhizogenes harboring Ri plasmid and cultured on phytohormone-free Murashige and Skoog medium after eliminating the bacteria. Hairy roots grew vigorously and sometimes formed yellowish calli under dark conditions. On the other hand, growth of hairy roots stopped after several weeks of culture with light, then shoots were regenerated. Frequency of shoot formation from hairy roots increased as the culture period in light lengthened and the light intensity increased. The shoot regeneration was induced by treatment with white or red light, but not with far-red light. Shoot regeneration by red light was inhibited by following treatment with far-red light. Red and far-red light reversibly affected shoot regeneration. Excised roots of nontransformed plants grew quite slowly on phytohormone-free Murashige and Skoog medium and occasionally formed shoots under white light conditions. PMID:16669041

  4. Shoot Regeneration from Leaf Explants of Withania somnifera (L. Dunal

    Aruna Girish JOSHI


    Full Text Available Regeneration from leaf explants of Withania somnifera (L. for mass propagation was studied on Murashige and Skoog�s medium supplemented with Kinetin (Kn and 6-benzylaminopurine (BAP alone or in combination. Shoot buds were induced from the midrib on the abaxial side in presence of Kn and BAP (4 �M. These shoot buds developed into shoots on the same medium. Rooting of these shoots was achieved in 0.5 �M of IBA.

  5. High frequency shoot regeneration of Sterculia urens Roxb. an ...



    Jul 18, 2007 ... ingredient in the preparation of emulsions, lotions, denture fixative powders, bulk ... the wood leads to borer attack, which may prove fatal. Unscientific .... cytokinin had a significant effect on the frequency of shoot regeneration ...

  6. Shoot and plantlet regeneration from meristems of Dioscorea ...



    Apr 17, 2008 ... In vitro culture media capable of regenerating moderate to high shoots and/or plantlets from meristems of two yam ..... Pvt. Ltd, Naraina, New Delhi, India, pp. ... development in medicinal yam in relation to planting material and.

  7. Adventitious Shoot Regeneration from Leaf of Uenishiwase Persimmon

    MA Jun-lian; LIU Xiao-na; ZHANG Zi-de


    Effects of basal mediums, hormones and their concentrations on the shoot regeneration from leaf of sweet persimmon (Diospyros kaki Thunb. Cv. Uenishiwase) were studied by orthogonal design trial. The result showed that modified Murashige and Skoog [MS (1/2 N)] was the most optimum for the regeneration and 1/2 MS was better than MS. Shoot percentage in the medium containing 4.0 mg L-1 ZT(zeatin) was much higher than that of other two concentrations, among which 2.0 mg L-1 ZT was much better than 1.0 mg L-1 ZT and shoot percentage in the concentration of 1.0 mg L-1 ZT was only 4%. There were no any beneficial effects when supplementing IAA in the medium. Shoot percentage and average shoots perexplantsweredramaticallydecreasedinthe 2.0 mg L-1 IAA. Data in the orthogonal trial indicated that ZT was the most effective factor in the shoot regenerating of Uenishwase persimmon and basal medium was important too, but IAAhad no any beneficial effects at all. In the orthogonal trial, the best result was achieved in MS (1/ 2 N) medium containing 4.0 mg L-1 ZT and 1.0 mg L-1 IAA, in which shoot percentage and average shoots per explants were 86% and 2.2, respectively.

  8. Shoot multiplication and plant regeneration in Caragana fruticosa (Pall.) Besser

    ZHAI Xiao-jie; YANG Ling; SHEN Hai-long


    Different nutrient media can affectin vitro culturing protocols,and experimentation under varied growth conditions is valuable in plants where in vitro methods are in preliminary stages.We carried out the first in vitro propagation studies for the endangered species Caragana fruticosa (Fabaceae).We evaluated various nutrient media for their inpact on shoot elongation and axillary bud proliferation using different concentrations of 6-benzylaminopurine (BA) and α-naphthaleneacetic acid (NAA).Shoot elongation was evaluated based on adventitious shoot primary culture and subculture regeneration from Caragana seedlings.Our goal was to improve both micropropagation and regeneration in C.fruticosa.MS nutrient media was superior to 1/2MS macronutrients,DKW,QL,and WPM for shoot elongation and axillary shoot proliferation.Shoots grown on 1/2MS and WPM exhibited some chlorosis,and shoots on QL produced larger leavers than plants growing on normal medium.The shoot proliferation coefficient on MS media supplemented with 2.22 μM BA and 0.44 μM BA + 2.69 μM NAA was significantly higher than that with other treatments in the primary culture.Shoots on 2.22 μM BA showed a higher proliferation coefficient (3.17) than others in the subculture.Shoots were rooted on 1/2MS medium with the addition of different concentrations of NAA.The optimal concentration for rooting was 0.27 μM NAA (74%).Roots exhibited many stout and long root hairs.Survivl of established plantlets was 82% at 30 days after transfer to soil.Plants established in the green house showed normal growth and displayed no apparent morphological differences compared to stock plants.

  9. In vitro regeneration and induction of multiple shooting in Cicer ...


    importance as a source of food and fodder; its straw has forage value ... improvement efforts like Agrobacterium mediated gene .... Effect of different concentrations of BAP on multiplication of C. arietinum L. (vr. Desi of ... development and shoot quality. ..... Transformation of maize protoplast and regeneration of haploid.

  10. Shoot regeneration from petioles and leaves of Vitis X labruscana 'Catawba'.

    Cheng, Z M; Reisch, B I


    Shoot regeneration and normal plants were obtained from leaf and petiole explants derived from in vitro grown shoots of Vitis X labruscana 'Catawba'. Regeneration was induced in the presence of both 6-benzylaminopurine and indole-3-butyric acid; combinations of 2,4-dichlorophenoxyacetic acid or 2-naphthoxyacetic acid with 6-benzylaminopurine did not permit regeneration from leaf explants. Up to 15% of leaf and 70% of petiole explants regenerated shoots on media with 5.0-10.0 μM BA and 0.1-0.5 μM IBA. Incubation in the dark was required to obtain regeneration. About 50% of shoots developed normally following transfer to light. An average of one shoot regenerated from leaf explants and 3.3 shoots regenerated per petiole explant. Regeneration from petioles and leaves was always from the basipetal end. The interaction of 6-benzylaminopurine with indole-3-butyric acid was also examined.

  11. Adventitious shoot regeneration from leaf explants of southern highbush blueberry cultivars

    Protocols were developed to optimize adventitious shoot regeneration from four southern highbush blueberry cultivars. Leaf explants from six-week-old shoots of the four cultivars were excised and cultured on ten WPM (woody plant medium)-based regeneration media each containing thidiazuron (TDZ) (4.5...

  12. Adventitious shoot regeneration from the leaves of in vitro grown 'Zhongli 1' pear (Pyrus spp.)

    Jie LIU; Xi ZHANG; Bharat Kumar POUDYAL; Yuxing ZHANG; Zhan JIAO; Jing QI


    The pear (Pyrus spp.) is one of the most important temperate fruit crops. The technique of adven-titious shoot regeneration from leaves is considered to be one of the shortcuts in the research on pear genetic modification and cellular engineering, which, however, has not been widely used. As the regeneration frequency of pear leaves is usually very low, the research on adventi-tious shoot regeneration from pear leaves is eagerly needed. In this experiment, the factors affecting shoot and bud regeneration from the leaves of 'Zhongli 1' pear were studied, and an efficient protocol for shoot regenera-tion was established. The results showed that different types of basic media, different combinations of plant growth regulators, leaf placement on medium, periods of dark culture and the use of silver nitrate (AgNO3) on culture media all significantly affected the adventitious shoot regeneration frequency of 'Zhongli 1' pear. The details are as follows: (1) Among three kinds of basic media, NN69 was better for 'Zhongli 1' shoot regenera- tion, followed by half(1/2) MS, while full MS had no effect on shoot regeneration; (2) Thidiazuron (TDZ) was better than 6-benzylaminopurine (6-BA) for 'Zhongli 1' regen-eration, with an optimal concentration of 1.5 mg.L-1, and the regeneration rate under this concentration could reach 85%, with 2.72 buds per leaf. 0.5 mg .L-1 indole-3-butyric acid (IBA), which induced a higher regeneration fre-quency, was a better choice for pear regeneration compared with 0.3 mg.L-1 naphthaleneacetic acid (NAA). Among the different combinations of plant growth regulators, TDZ + IBA was better for inducing high regeneration frequency; (3) The abaxial surface of leaves touching the medium was beneficial for leaves to uptake nutrients from the medium, and because of that, the regeneration fre-quency of leaves was significantly higher than that of leaves touching the medium with their adaxial surfaces (obverse side of leaf); (4) Dark culture was necessary

  13. AgNO3 boosted high-frequency shoot regeneration in Vigna mungo (L.) Hepper.

    Mookkan, Muruganantham; Andy, Ganapathi


    In order to further increase shoot regeneration frequency of Vigna mungo (L.) Hepper., the effects of AgNO3 on this process was investigated in this study. The shoot tip and cotyledonary node explants were cultured on MS salts B5 Vitamins medium containing BA+TDZ+Ads+AgNO3 for multiple shoot induction. AgNO3 influenced the shoot bud formation and their subsequent proliferation. The best medium composition for multiple shoot induction was BA, TDZ combination with Ads and AgNO3 in MSB5 medium. Maximum 39 shoots in cotyledonary node and 22 shoots in shoot tip were obtained per explants after 4 - 6 wk. of culture. Elongation and rooting were performed in GA3 (0.6mg/l) and IBA (0.4mg/L) containing media respectively. The in vitro raised plantlets were acclimatized in green house and successfully transplanted to the field with a survival rate of 78%.

  14. Adventitious shoot regeneration from the leaves of some pear varieties (Pyrus spp.) grown in vitro

    Bharat Kumar POUDYAL; Yuxing ZHANG; Guoqiang DU


    The pear (Pyrus spp.) is one of the most important temperate fruit crops. A complete protocol for adventitious shoot regeneration was developed from the leaves of four pear varieties grown in vitro: Abbe Fetel, Yali, Packham's Triumph and Aikansui, and the Chinese rootstock variety Dull. Shoot explants were collected from the field and cultured in vitro in Murashige and acid (IBA). After four weeks, leaf explants of all 5 varieties grown in vitro were excised and cultured in MS cultures were maintained in darkness for 21 days for shoot induction in the shoot induction medium (IM), then transferred to the shoot expression medium (EM) in room at (25±2)℃ under a 16/8 h light/dark photoperiod regime for 8 weeks. Finally, the shoots were transferred to the MS shoot elongation medium (SEM) supplemented gibberellic acid (GA3). A combination of TDZ and NAA had a significant effect on the number of shoot regenera-tions in all 5 tested varieties. The maximum mean number of shoots and maximum number of shoots per leaf obtained from Yali variety were 11.8 (P≤0.001) and 22, followed by Aikansui with 6.6 (P≤0.001) and 4.6, and Duff with 8 (P≤0.001) and 12, all arising from the For Packham's Triumph and Abbe Fetel, the maximum mean number of shoots and maximum number of shoots per leaf were 5.6 (P≤0.001), 4.8 and 8 (P≤0.001), and 11, which produced significantly higher adventitious shoots problems associated with shoot proliferation and regenera-tion were also observed and discussed in this paper.

  15. In vitro regeneration of Centaurium erythraea Rafn from shoot tips and other seedling explants

    Ewelina Piątczak


    Full Text Available Various explants from 30-day-old seedlings of Centaurium erythraea Rafn were evaluated for their morphogenetic capacity under in vitro culture conditions. Shoot formation from shoot tip explants was achieved mainly through adventitious bud differentiation. The highest number of shoots (up to 43.3 ± 2.2 from a single shoot tip was obtained on Murashige and Skoog medium (MS supplemented with indole-3-acetic acid (IAA (0.57 μM and 6-benzylaminopurine (BAP (4.4 μM. Adventitious shoot regeneration was also achieved through organogenesis from calluses obtained from hypocotyls, cotyledons, roots and leaves on MS medium containing IAA (2.85 μM and BAP (0.88 μM. Significant differences were noted between explant types in their effects on shoot regeneration. In the primary culture, the best response was obtained either from calluses derived from roots or leaves (44.4 ± 4.5 and 40.2 ± 6.0 shoots per callus, respectively. The number of subcultures of inoculated calluses affected both the multiplication rate (the number of shoots/explant and shoot morphology (the frequency of shoot hyperhydricity. Shoots rooted with the frequency of 94-100% after culture on MS medium without growth regulators. Plantlets were successfully acclimatized (97% under high relative humidity and then moved to the greenhouse.

  16. Multiple shoot-bud formation and plantlet regeneration on Castanea sativa Mill. seeds in culture.

    Rodríguez, R


    Primordial initiation and development of shoot-buds has been accomplished by using shoots derived from chestnut (Castanea sativa Mill) seedlings cultured with added 6-benzylaminopurine (BAP). Germination of chestnut seeds in the presence of BAP (4 - 40 μM) stimulated varying numbers of shoot-buds in those areas of the main axis that were favorably altered. When excised single shoots from these treated seeds were subcultured on a fresh medium containing BAP (4 - 40 μM) continual shoot production was observed. Bud growth and shoot elongation were stimulated by transferring cultures to a reduced concentration of BAP (2 μM) plus indole-3-butyric acid (IBA 0.4 μM). Plant regeneration occurred in the presence of IBA (0.8 μM) after a preconditioning treatment in which naphthaleneacetic acid (NAA 50 μM) and kinetin (k 2 μM) were applied to the tissue culture shoots for 7 days in light.

  17. Assessment of factors affecting in vitro shoot regeneration from axillary bud explant of Camptotheca acuminata

    WANG Hui-Mei; ZU Yuan-Gang; DONG Feng-Li; ZHAO Xiao-Ju


    Axillary buds from 3-yr.-old seedlings of Camptotheca acuminata in the greenhouse were cultured on the different basal media with different concentrations of growth regulators for shoot regeneration for studying the effects of different basal media, different concentrations of growth regulators (BA or TDZ), sucrose, agar and pH value on shoot regeneration from axillary bud. The results showed that B5 and WPM media were the optimal basal media and the optimal phyotohormone was BA of 1.0 mg/L or TDZ of 0.1mg/L; The concentrations of sucrose of 30g/L and agar of 6g/L were most suitable for the shoot regeneration; pH value from 5.8 to 6.6 were broadly effective, but the best at pH 5.8.

  18. Highly efficient in vitro adventitious shoot regeneration of Adenosma ...



    Apr 10, 2012 ... Druce is an important aromatic plant, but no information is available regarding its regeneration ... author. E-mail:; .... percentage of adventitious bud induction and the average number of adventitious buds ...

  19. Adventitious shoot regeneration from cultured leaf explants of Petunia



    Jun 26, 2012 ... Department of Plant production and Protection, Faculty of Agriculture, An-Najah National University. Nablus ... 1993), nitrogen and calcium effect on regeneration (Frett and Dirr ..... dehydrogenase, and peroxidase activities.

  20. Cytokinin induced shoot regeneration and flowering of Scoparia dulcis L. (Scrophulariaceae)-an ethnomedicinal herb

    Premkumar G; Sankaranarayanan R; Jeeva S; Rajarathinam K


    Objective: To develop an improved protocol for micropropagation of ethnomedicinally important Scoparia dulcis (S. dulcis) L. Methods: Explants were inoculated on MS basal medium supplemented with kinetin and 6-benzylaminopurine for shoot bud induction. To enhance the shoot induction, various auxins like 3-indoleacetic acid or 3-indolebutyric acid or α-naphthylacetic acid were tested along with 2.32 M KI and 4.44 μM BAP. The regenerated shoots were rooted in half strength MS medium supplemented with various concentrations of IAA, IBA or NAA. After roots were developed, the plantlets were transplanted to pots filled with vermiculate and sand and kept in growth chamber with 70%-80% humidity under 16 h photoperiod. After acclimatization, the plantlets were transferred to the garden and survival percentage was calculated. Data were statistically analyzed and means were compared using Duncan's multiple range test (P<0.05). Results: An in vitro method was developed to induce high frequency shoots regeneration from stem, mature leaf and young leaf explants of S. dulcis. Shoot induction on young leaf explants was most successful in MS medium supplemented with combination of two cytokinins (2.32 μM KI and 4.44 μM BAP) 2.85 μM IAA, 10% CM and 1 483.79 μM adenine sulfate. A single young leaf explant was capable of producing 59 shoots after 13 days of culture. Flower was induced in medium supplemented with combination of KI and BAP. Conclusions:Cytokinins are the key factor to induce the direct shoot regeneration and flowering of S. dulcis.

  1. Shoot regeneration from cotyledonary leaf explants of jatropha curcas: A biodiesel plant

    Kumar, Nitish Chandramohana


    A simple, high frequency, and reproducible method for plant regeneration through direct organogenesis from cotyledonary leaf explants of Jatropha curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ) or 6-benzyl aminopurine (BAP). Medium containing TDZ has greater influence on regeneration as compared to BAP. The induced shoot buds were transferred to MS medium containing 10 lM kinetin (Kn), 4.5 lM BAP, and 5.5 lM a-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with different concentrations and combinations of BAP, indole-3-acetic acid (IAA), NAA, and indole-3-butyric acid (IBA). MS medium with 2.25 lM BAP and 8.5 lM IAA was found to be the best combination for shoot elongation. However, significant differences in plant regeneration and shoot elongation were observed among the genotypes studied. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing dif- ferent concentrations and combinations of IBA, IAA, and NAA for 4 days, followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg l-1 activated charcoal. Elongated shoot treated with 15 lM IBA, 5.7 lM IAA, and 11 lM NAA resulted in highest percent rooting. The rooted plants could be established in soil with more than 90% survival rate. The method developed may be useful in improvement of J. curcas through genetic modification. © Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków 2010.

  2. Efficient regeneration of pearl millet (Pennisetum glaucum (L.) R. Br.) from shoot tip cultures.

    Mythili, P K; Madhavi, A; Reddy, V D; Seetharama, N


    A simple, genotype-independent and efficient method for plant regeneration using shoot tip explants of pearl millet (Pennisetum glaucum) was established. Linsmaier and Skoog (LS) medium supplemented with 2,4-dichloro-phenoxyacetic acid (2.5 mg l(-1)) and kinetin (0. 2 mg l(-1)) was used for induction of embryogenic calli. Development of numerous somatic embryos was observed within 10 days after transferring onto Murashige and Skoog (MS) medium supplemented with 6-benzyl aminopurine (2 mg l(-1)) and indole 3-butyric acid (0. 5 mg l(-1)) under light (16 hr photoperiod). Histological observations confirmed the origin of somatic pro-embryoids and globular embryoids. Regenerated plants established in soil, grew normally and produced fertile seeds. RAPD analysis also revealed genetic uniformity of the regenerants. The short duration of time taken for regeneration (30-35 days) and its high frequency (78-87%) makes this system highly suitable for applications such as genetic transformation.

  3. In vitro multiple shoot regeneration and plant production in Alysicarpus rugosus DC. var. heyneanus Baker.

    Bhosle, S V; Thengane, R J; Thengane, S R


    A protocol for in vitro multiple shoot regeneration and plant production through seedling (shoot tip) culture was established for Alysicarpus rugosus DC. var. heyneanus Baker. Maximum number of adventitious shoots (14.4) per shoot tip explant were initiated after two subcultures on MS solid medium supplemented with IAA (2.85 microM) plus BAP (2.22 microM) after 4 weeks. Shoot elongation (3.0-3.5 cm) was achieved on MS medium without any hormones. Stunted shoots elongated on half MS medium without growth hormones. Rooting occurred in MS medium containing IAA (1.14 - 2.85 microM) alone or in combination with IBA (0.89 - 2.46 microM) and or NAA (1.07 - 2.69 microM). Maximum rooting was established in MS medium supplemented with IAA (2.85 microM). The plants were acclimatized successfully with 55% survival in pot containing cocoa peat and sand (1:1). After a month, hardened plants were transferred to pots with manure, garden soil and sand (1:2:1) for further growth and finally planted in field.

  4. Shooting



    @@ Shooting with the rifle, pistol and shotgun2 has been practiced in many countries since the Middle Ages. During the 19th century, however,shooting also developed into a sport: associations, federations,councils, confederations, unions or organizations were formed in some countries, using different words to describe the alliance3 of shooters in clubs or the alliance clubs in local, regional or national organizations.

  5. Silicon Promotes Adventitious Shoot Regeneration and Enhances Salinity Tolerance of Ajuga multiflora Bunge by Altering Activity of Antioxidant Enzyme

    Iyyakkannu Sivanesan


    Full Text Available We investigated the effect of Si concentration on shoot regeneration and salinity tolerance of Ajuga multiflora. Addition of Si to the shoot induction medium significantly increased the frequency of shoot induction. The average number of shoots regenerated per explant decreased on the medium containing NaCl alone, while there was less decrease when the shoot induction medium was supplemented with both NaCl and Si. The shoot induction percentage increased linearly with increasing concentration of Si in the NaCl containing medium. Addition of Si to the shoot induction medium significantly increased SOD, POD, APX, and CAT activity in regenerated shoot buds as compared with the control. The inclusion of Si to the NaCl containing medium significantly increased the SOD activity in leaves and roots, while it decreased POD, APX, and CAT activity in both organs. Scanning electron microscopic analysis showed that there are no distinct differences in the structure of stomata between the control and Si-treated plants. However, NaCl treatment significantly affected the structure and number of stomata as compared to the control. Wavelength dispersive X-ray analysis confirmed the high Si deposition in trichomes of plants grown in the Si containing medium but not in plants grown in the medium without Si.

  6. In vitro direct shoot regeneration from proximal, middle and distal segment of Coleus forskohlii leaf explants.

    Krishna, Gaurav; Sairam Reddy, P; Anoop Nair, N; Ramteke, P W; Bhattacharya, P S


    Coleus forskohlii is an endangered multipurpose medicinal plant that has widespread applications. In spite of this, there have been few attempts to propagate its cultivation in India. The present communication presents an in vitro rapid regeneration method using leaf explants of Coleus forskohlii through direct organogenesis. Leaf explants that were excised into three different segments i.e. proximal (P), middle (M) and distal (D) were cultured on Murashige and Skoog (MS) basal medium supplemented with cytokinins. MS Media containing 5.0 mg L(-1) BAP (6-Benzylaminopurine) promoted regeneration of multiple shoots through direct organogenesis from the leaf, which were further elongated on MS media augmented with 0.1 mg L-1 BAP and 0.1 mg L(-1) IAA (Indole-3-acetic acid), cytokinin and auxin combination. Regenerated and elongated shoots, when transferred to ose resulted in profuse rooting plants that were transferred to soil after acclimatization and maintained in a green house. The current protocol offers a direct, mass propagation method bypassing the callus phase of C. forskohlii and is suitable for conservation, large-scale commercial cultivation, and genetic transformation with agronomically desirable traits.

  7. Regeneration of Dioscorea floribunda plants from cryopreserved encapsulated shoot tips: effect of plant growth regulators.

    Mandal, B B; Ahuja-Ghosh, Sangeeta


    The encapsulation-dehydration protocol for the cryopreservation of in vitro shoot tips of Dioscorea floribunda was optimized. Maximum survival of 87% was obtained when overnight pretreatment with 0.3 M sucrose was followed by encapsulation, preculture in 0.75 M sucrose for 4 d, dehydration in a laminar air flow for 5.5 h, quenching in liquid nitrogen and thawing at 40 degrees C. During recovery growth, 29% shoot formation was obtained when cryopreserved shoot tips were initially cultured for 25 d on a medium with 1.5 mg per liter (-1) BAP, 0.2 mg per liter(-1) NAA and 0.2 mg per liter(-1) GA3 followed by culturing for 15 d on a medium with reduced BAP (1 mg per liter(-1)) but increased NAA (0.5 mg per liter(-1)) and GA3 (0.3 mg per liter(-1)). Finally, transfer on to a medium with further reduced doses of BAP (0.05 mg per liter(-1)) and NAA (0.15 mg per liter(-1)) but without GA3 stimulated production of fully grown plantlets. All plants regenerated without callus formation. Modification of post-thaw culture media with plant growth regulators was essential for regrowth of shoot tips to plantlets.

  8. Shooting

    Fells, Nick


    Shooting (2005) was an installation undertaken in collaboration with Ghanaian sculptor Kofi Setordji. It was created as part of an artist residency at Villa Waldberta, Feldafing, near Munich. The installation presented a time-varying overlay of recordings made in the artist’s studio whilst he was working; the sounds are those of the materials and processes of the working sculptor. The piece was created in the MAX environment, and played back in the exhibition space around and about the sculpt...

  9. [Somatic embryogenesis and plant regeneration in vitro from young shoots of Aralia elate (Miq.) Seem].

    Li, J M; Li, X W; Zhang, D Y; Xing, M


    Explants excised from the young shoots of Aralia elata (Miq.) Seem. were cultured on MS media. Calli were induced from the explants on MS medium supplemented with 0.5 mg/L 2, 4-D, 0.5 mg/L BA and 0.5 mg/L NAA. Then these calli were transferred onto the MS medium containing 2.0 mg/L 2,4-D + 0.5 mg/L BA + 0.5 mg/L NAA and 0.2% activated charcoal. Under these conditions the somatic embryoids were observed and regenerated plants were obtained from somatic embryogenesis. Then, a experimental system with stability and high regenerating efficiency has been set up for the propagation of the young plants, the cell breeding technology and the control of somatic embryogenesis of Aralia elata (Miq.).

  10. Shoot regeneration from leaf petioles of iles-iles (Amorphophallus muelleri Blume



    Full Text Available Iles-iles (Amorphophallus muelleri Blume of the Araceae is a source of carbohydrate with a high content of glucomannan which is very useful in preventing several diseases like diabetes, high blood cholesterol, high blood pressure, etc. In industry, the tuber is used as a raw material for paper pulp, textile, gum, celluloid, food and cosmetics. Generally, iles-iles is propagated by splitting tubers, bulbils or leaf cuttings, but this method can not yield high quality planting materials and sometimes may carry along many diseases. In this investigation, an in vitro method for shoot regeneration of iles-iles from petiole explants was developed. Sterilization of the explants was carried out in 0.05% HgCl2 for 20 min. after dipping in 70% ethanol and Tween 20 solution. Leaf petioles about 1 cm in length were cultured on Murashige & Skoog (MS medium with a pH of 5.8 containing 30 g sucrose and 2.5 g Gelrite agar. The formation of adventives shoots was induced on MS medium containing 1, 2, and 4 mg/L Benzyl Amino Purine (BAP either with or without the addition of 0.1, 0.2 and 0.5 mg/L Naphthalene Acetic Acid (NAA. Each treatment was done on 10 explants. All cultures were incubated at 26°C on a 16-h photoperiod with an illumination of 30 μmol m-2 sec-1 provided by 40-W cool white inflorescent lights. The highest rate of shoot multiplication averaging 19 shoots per explants was achieved within 3 months on MS medium containing 2 mg/L BAP. However, the best shoot elongation was found on MS medium containing 2 mg/L BAP and 0.2 mg/L NAA.


    Shastri P. Shukla


    Full Text Available An efficient regeneration protocol was developed from shoot tip and nodal explants of Simarouba glauca DC, a promising biodiesel plant. Nodal explants appeared to have better regeneration capacity than shoot tip explants (40% in the tested media. The highest regeneration frequency (90% and shoot number (7.00 ± 1.00 shoots per explants were obtained in nodal explants in Murashige and Skoog’s (MS medium supplemented with 6-benzylaminopurine (BAP 4.43 μM and α-naphthalene acetic acid (NAA 5.36 μM.Induced shoot buds were multiplied and elongated on the MS medium supplemented with BAP (4.44 μM, NAA (5.36 μM and TDZ (Thidiazuron 2.27 μM with 9.66±0.33 (mean length 5.35±0.32 cm and 9.00±0.57 (mean length 4.51±0.15cm shoots using nodal segments and shoot tip explants, respectively. Halfstrength woody plant medium (WPM containing 2.46μM indole-3-butyric acid (IBA produced the maximum number of roots (6.00±1.15. The rooted plantlets were hardened on MS basal liquid medium and subsequently in polycups containing sterile soil and vermiculite (1:1 and successfully established in pots.

  12. In vitro adventitious shoot regeneration via indirect organogenesis from petiole explants of Cassia angustifolia Vahl.-a potential medicinal plant.

    Siddique, Iram; Anis, M; Aref, I M


    An effective protocol was developed for in vitro regeneration of the Cassia angustifolia via indirect organogenesis from petiole explants excised from 21-day-old axenic seedlings. Organogenic callus were induced on Murashige and Skoog (MS) medium supplemented with 5.0 µM 2,4-dichlorophenoxy acetic acid and 2.5 µM thidiazuron (TDZ). Adventitious shoot regeneration was achieved on MS medium supplemented with 5.0 µM TDZ as it induced 8.5 ± 0.98 shoots in 85% cultures. The number of shoots and shoot length was significantly enhanced when cultures were subcultured on auxin-cytokinin-containing medium. The highest number of shoots (12.5 ± 1.10) and shoot length (4.3 ± 0.20 cm) was recorded on MS medium supplemented with 5.0 µM TDZ and 1.5 µM indole-3-acetic acid. Regenerated shoots were rooted best on MS medium supplemented with 10.0 µM indole-3-butyric acid followed by their transfer to liquid MS filter paper bridge medium. The plants were successfully hardened off in sterile soilrite followed by their establishment in garden soil with 70% survival rate. The plants showed normal morphological characteristics similar to the field grown plants.

  13. Shoot regeneration from GUS-transformed tomato (Lycopersicon esculentum) hairy root.

    Moghaieb, Reda E A; Saneoka, Hirofumi; Fujita, Kounosuke


    To study the influence of genetic background on the transformation and regeneration of cultivated tomato plants, hairy root lines of tomato (Lycopersicon esculentum) were obtained by inoculating the hypocotyl explants of three tomato cultivars with the Agrobacterium rhizogenes strain DCAR-2, which harbors the pBI-121 binary vector. The Ri-T-DNA transformation into the plant DNA was confirmed by both of mikimopine and GUS assay analyses. The regeneration efficiency from hairy root explants was assessed. The data indicated that white embryonic calli were formed within two weeks in the presence of 2 mgl(-1) 2, 4-D plus 0.25 mgl(-1) kinetin. Adventitious shoots emerged from the embryonic callus in the presence of 1 mgl(-1) GA3 along with 0.5 mgl(-1) NAA. The regeneration frequency was higher in the cultivar UC-97, followed by Momotaro and then Edkawi. Molecular confirmation of the integration of the GUS gene into the hairy root-derived plants genomes was done via PCR using GUS-specific primers and also using Southern blotting analysis. Our data shows that regeneration is possible from hairy roots of the cultivated tomato and this system could be used to produce transgenic tomato plants expressing the genes present in Agrobacterium rhizogenes binary vectors.

  14. Shoot organogenesis in leaf explants of Hydrangea macrophylla ‘Hyd1’ and assessing genetic stability of regenerants using ISSR markers

    Liu, F.; Huang, L.L.; Reinhoud, P.; Jongsma, M.A.; Wang, C.


    For the first time, an in vitro regeneration protocol of Hydrangea macrophylla 'Hyd1' was developed. Effects of different plant growth regulators (PGRs) on shoot regeneration were investigated jointly with selecting optimal basal media and cefotaxime concentrations. The highest frequency of shoot or

  15. Regeneration of transformed shoots from electroporated soybean (Glycine max (L.) Merr.) protoplasts.

    Dhir, S K; Dhir, S; Sturtevant, A P; Widholm, J M


    Stable transformation of soybean (Glycine max (L.) Merr.) protoplasts isolated from immature cotyledons was achieved following electroporation with plasmid DNA carrying chimeric genes encoding ß-glucuronidase (GUS) and hygromycin phosphotransferase (HPT) under the control of the cauliflower mosaic virus (CaMV) 35S promoter. Transformed colonies were stringently selected by growing 15-day-old protoplast-derived cells in the presence of 40 μg/ml of hygromycin-B for 6 weeks. Over 93% of the resistant cells and colonies exhibited GUS activity, indicating that the two marker genes borne on a single plasmid were co-introduced and co-expressed at a very high freguency. This transformation procedure reproducibly yields transformants at frequencies of 2.9-6.8 × 10(-4) (based on the number of protoplasts electroporated) or 23.0% (based on the number of control microcalli formed) counted after 6 weeks of selection. After repeated subculturing on regeneration medium, shoots were induced from 8.0% of the transformed calli. Southern hybridization confirmed the presence of both the GUS and hygromycin genes in the transformed calli and shoots.

  16. First Report of Plant Regeneration via Somatic Embryogenesis from Shoot Apex-derived Callus of Hedychium muluense

    Plants were successfully regenerated via somatic embryogenesis from shoot apex-derived callus of Hedychium muluense R.M. Smith, an important monocotyledonous ornamental ginger plant. Callus was induced on a modified Murashige and Skoog (MS) medium supplemented with 9.05 µM 2-4, D and 4.6µM kinetin. ...

  17. Establishment of multiple shoot clumps from maize(Zea mays L.) and regeneration of herbicide-resistant transgenic plantlets

    李国圣; 张卿伟; 张举仁; 毕玉平; 单雷


    A kind of quick, efficient and season-free inducing embryoid and multiple shoot clumps system from shoot tip meristems that derived from elite inbreds of maize was established. The herbicide-resistant gene als(coding Acetolactate synthase) isolated from a mutant of Arabidopsis thaliana was transferred to tissue pieces of maize multiple shoot clumps by microprojectile bombardment. Herbicide-resistant tissue and regenerants were obtained through selections with herbicide chlorsulfuron. PCR analysis and Southern blot hybridization indicated that gene als has been transferred to some regenerants. The test of spraying chlorsulfuron displayed that the transgenic plantlets and R1 plants had favorable herbicide-resistant trait. We have established a new genotype-free system of maize which could rapidly and efficiently produce large quantities of transgenic plantlets.

  18. Effects of thidiazuron and paclobutrazol on regeneration potential of tulip flower stalk explants in vitro and subsequent shoot multiplication

    Małgorzata Podwyszyńska


    Full Text Available The effects of TDZ and paclobutrazol on the primary regeneration on tulip flower stalk explants of six cultivars and subsequent shoot multiplication were examined. Explants, flower stalk slices, were excised from cooled and subsequently forced bulbs. The explants were incubated for two months in darkness on medium containing NAA and cytokinins, 2iP and BAP, as control, or TDZ (0.5-4 mg l-1 and paclobutrazol (0.05-0.4 mg l-1. Then, the regenerating explants were subcultured on medium with TDZ and NAA applied at low concentrations. Different regeneration capabilities were found depending on cultivar and growth regulators. The percentage of explants forming leaf-like structures ranged, on the control medium, from 80% in 'Blue Parrot' and 'Prominence' to below 30% in 'Apeldoorn' and 'Mirjoran'. TDZ, applied at optimum for each cultivar concentration, greatly increased the regeneration potential up to 70-100%. Paclobutrazol, added to the TDZ-containing medium, significantly enhanced the response of explants, resulting in high numbers of leaf-like structures formed per explant (13.7-22.8. The structures developed gradually into characteristic forms: the growing up cotyledonary leaf, the probable root primordium formed at its base, the growing downwards stolon and the shoot meristem developed finely on its tip. It is suggested that such primary regeneration may have a nature of somatic embryogenesis. Then, the adventitious shoots developed and formed clusters, which were divided into 2-3 smaller ones every two months. The growth regulators, used at initial stage, markedly influenced subsequent shoot multiplication. Thus, the most intensive shoot formation was noted with TDZ at concentrations of 0.5-2 mg l-1 and paclobutrazol of 0.05-0.1 mg l-1.

  19. In Vitro Regeneration of Shoots From Nodal Explants of Dendrobium Chrysotoxum Lindl

    Kaur Saranjeet


    Full Text Available Transverse sections (2 mm thickness of stem-nodes from in vitro raised seedlings had morphogenic potential on semisolid and liquid Murashige and Skoog medium supplemented with cytokinins N6-benzyladenine (BA 4.44 μM, furfurylaminopurine (KIN 4.65 μM and auxin α-naphthalene acetic acid (NAA 5.37 μM individually and in combinations. The regeneration response was influenced by both the type of growth regulator and physical state of the medium. The explants produced either shoot buds on cytokinincontaining media or protocorm-like bodies (PLBs on NAA containing media both solid and liquid. More neo-formations were produced on liquid media, especially those containing only NAA. They were formed at nodal and inter-nodal regions. The secondary buds were produced on the surface of primary PLBs. The plantlets were developed on MS medium containing banana homogenate 50 g·dm-3. The current study is the first ever report on successful regeneration of Dendrobium chrysotoxum from stem-node segments.

  20. In vitro establishment of a highly effective method of castor bean (Ricinus communisL.) regeneration using shoot explants

    ZHANG Ji-xing; CHI Yue; CHEN Yong-sheng; WANG Xiao-yu; FENG Zi-zhou; GENG Xue-jun; MU Sha-moli; HUO Hong-yan; TONG Huan; LI Meng-zhu; LI Yi


    An efifcient plant regeneration protocol was established for castor bean (Ricinus communisL.), in which 0.3 mg L–1 thidiazuron (TDZ) induced shoot clusters and increased the number of adventitious shoots from hypocotyl tissue. Our results showed that treatment under dark conditions signiifcantly promoted the average number of shoots per explant to 37.36±4.54 (with a 6-d treatment). Modiifed 1/2 Murashige and Skoog (MS) basal medium supplemented with 440 mg L–1 Ca2+, 0.2 mg L–1 gibberelic acid and 0.1 mg L–1 TDZ signiifcantly increased shoot elongation rates and lowered vitriifcation rates. Further-more, 1/2 MS media supplemented with 0.2 mg L–1 1-naphthaleneacetic acid induced a higher rooting rate compared with other culture conditions.

  1. Influence of cytokinins, basal media and pH on adventitious shoot regeneration from excised root cultures of Albizia lebbeck

    Shahnaz Perveen; Ankita Varshney; Mohammad Anis; Ibrahim M.Aref


    A highly reproducible and efficient in vitro shoot regeneration system was developed in a potential medicinal plant, Albizia lebbeck using root explants. Root explanns from 15 day-old-aseptic seedlings were cultured on Murashige and Skoog (MS) medium supplemented with different concentrations (0.5, 2.5, 5.0, 7.5 and 10.0 μM) of 6-Benzyladenine (BA),Kinetin (Kn), 2-lsopentenyl adenine (2-iP) singly as well as in combination with α-Naphthalene acetic acid (NAA) (0.1, 0.5, 1.0, 1.5 and 2.0 μM). The highest rate of shoot multiplication (16.0 ± 1.87 for the average shoot number and 5.16 ± 0.38 cm for shoot length) was achieved on MS medium supplemented with 7.5 tM BA and 0.5 tM NAA. The effects of medium type, medium strength, pH and subculture on shoot induction and proliferation were also tested. An average of 21.6±2.87 shoots per explants could be obtained following this protocol. Rooting was achieved on microshoots using half strength MS medium with 2.0 μM Indole-3-butyric acid (IBA) after four weeks of culture. The in vitro raised healthy plantlets were successfully established in earthen pots containing garden soil and grown in greenhouse with >80% survival rate.

  2. Biochemical investigations during in vitro adventitious shoot regeneration in leaflet explants from nodal segments of a mature Albizia procera tree

    Ekta Rai; Sulochna Bouddha; Shamim Akhtar Ansari


    The in vitro adventitious shoot differentiation in leaflet explants of an adult tree differed from that of leaflet explants of seedlings of Albizia procera (Roxb.) Benth. reported previously elsewhere. The leaflet explants from an adult tree passed through an initial callus phase for 30 days on MS medium supplemented with 3% sucrose, 2.5 lM 2,4-D followed by a subsequent adventitious shoot differentiation phase for another 30 days on half MS medium supplemented with 0.25 lM each of BA and IBA. The regeneration rate of in vitro adventitious shoots in explants from the adult tree, i.e.1.66 shoots/callus, was lower than that from seedlings, i.e. [10 shoots/callus, which was reported elsewhere. Correspondingly, the activities of nitrate reductase and peroxidase, and endogenous phenol content remained very low during in vitro adventitious shoot differentiation in leaflet explants of an adult tree possibly due to lower availability of competent stem (juvenile) cells for the process.

  3. Zebrafish Müller glia-derived progenitors are multipotent, exhibit proliferative biases and regenerate excess neurons.

    Powell, Curtis; Cornblath, Eli; Elsaeidi, Fairouz; Wan, Jin; Goldman, Daniel


    Unlike mammals, zebrafish can regenerate a damaged retina. Key to this regenerative response are Müller glia (MG) that respond to injury by reprogramming and adopting retinal stem cell properties. These reprogrammed MG divide to produce a proliferating population of retinal progenitors that migrate to areas of retinal damage and regenerate lost neurons. Previous studies have suggested that MG-derived progenitors may be biased to produce that are lost with injury. Here we investigated MG multipotency using injury paradigms that target different retinal nuclear layers for cell ablation. Our data indicate that regardless of which nuclear layer was damaged, MG respond by generating multipotent progenitors that migrate to all nuclear layers and differentiate into layer-specific cell types, suggesting that MG-derived progenitors in the injured retina are intrinsically multipotent. However, our analysis of progenitor proliferation reveals a proliferative advantage in nuclear layers where neurons were ablated. This suggests that feedback inhibition from surviving neurons may skew neuronal regeneration towards ablated cell types.

  4. Regeneration of Pea (’Pisum sativum L’.) Plants from Shoot Apical Meristems,

    A procedure has been developed to obtain complete plants from meristems of three cultivars of Pisum sativum L. Benzyladenine (BA) alone or in...combination with naphthaleneacetic acid (NAA) at molar concentrations of 5 x .0000005 and .000001 respectively, induced shoot differentiation in meristems ...complete plant formation. Root formation, on the shoots produced by culturing meristems was induced by reculturing the shoots, 2 cm long, on half strength B5 medium supplemented with NAA at a concentration of .000001 M.

  5. Ectopic expression of class 1 KNOX genes induce adventitious shoot regeneration and alter growth and development of tobacco (Nicotiana tabacum L) and European plum (Prunus domestica L).

    Srinivasan, C; Liu, Zongrang; Scorza, Ralph


    Transgenic plants of tobacco (Nicotiana tabacum L) and European plum (Prunus domestica L) were produced by transforming with the apple class 1 KNOX genes (MdKN1 and MdKN2) or corn KNOX1 gene. Transgenic tobacco plants were regenerated in vitro from transformed leaf discs cultured in a medium lacking cytokinin. Ectopic expression of KNOX genes retarded shoot growth by suppressing elongation of internodes in transgenic tobacco plants. Expression of each of the three KNOX1 genes induced malformation and extensive lobbing in tobacco leaves. In situ regeneration of adventitious shoots was observed from leaves and roots of transgenic tobacco plants expressing each of the three KNOX genes. In vitro culture of leaf explants and internode sections excised from in vitro grown MdKN1 expressing tobacco shoots regenerated adventitious shoots on MS (Murashige and Skoog 1962) basal medium in the absence of exogenous cytokinin. Transgenic plum plants that expressed the MdKN2 or corn KNOX1 gene grew normally but MdKN1 caused a significant reduction in plant height, leaf shape and size and produced malformed curly leaves. A high frequency of adventitious shoot regeneration (96%) was observed in cultures of leaf explants excised from corn KNOX1-expressing transgenic plum shoots. In contrast to KNOX1-expressing tobacco, leaf and internode explants of corn KNOX1-expressing plum required synthetic cytokinin (thidiazuron) in the culture medium to induce adventitious shoot regeneration. The induction of high-frequency regeneration of adventitious shoots in vitro from leaves and stem internodal sections of plum through the ectopic expression of a KNOX1 gene is the first such report for a woody perennial fruit trees.

  6. Characterization of the early proliferative response of the rodent bladder to subtotal cystectomy: a unique model of mammalian organ regeneration.

    Charles C Peyton

    Full Text Available Subtotal cystectomy (STC; surgical removal of ∼75% of the rat urinary bladder elicits a robust proliferative response resulting in complete structural and functional bladder regeneration within 8-weeks. The goal of these studies was to characterize the early cellular response that mediates this regenerative phenomenon, which is unique among mammalian organ systems. STC was performed on eighteen 12-week-old female Fischer F344 rats. At 1, 3, 5 and 7-days post-STC, the bladder was harvested 2-hours after intraperitoneal injection of bromodeoxyuridine (BrdU. Fluorescent BrdU labeling was quantified in cells within the urothelium, lamina propria (LP, muscularis propria (MP and serosa. Cell location was confirmed with fluorescently co-labeled cytokeratin, vimentin or smooth muscle actin (SMA, to identify urothelial, interstitial and smooth muscle cells, respectively. Expression of sonic hedgehog (Shh, Gli-1 and bone morphogenic factor-4 (BMP-4 were evaluated with immunochemistry. Three non-operated rats injected with BrdU served as controls. Less than 1% of cells in the bladder wall were labeled with BrdU in control bladders, but this percentage significantly increased by 5-8-fold at all time points post-STC. The spatiotemporal characteristics of the proliferative response were defined by a significantly higher percentage of BrdU-labeled cells within the urothelium at 1-day than in the MP and LP. A time-dependent shift at 3 and 5-days post-STC revealed significantly fewer BrdU-labeled cells in the MP than LP or urothelium. By 7-days the percentage of BrdU-labeled cells was similar among urothelium, LP and MP. STC also caused an increase in immunostaining for Shh, Gli-1 and BMP-4. In summary, the early stages of functional bladder regeneration are characterized by time-dependent changes in the location of the proliferating cell population, and expression of several evolutionarily conserved developmental signaling proteins. This report extends

  7. Asymmetric somatic hybridization between UV-irradiated Citrus unshiu and C. sinensis: regeneration and characterization of hybrid shoots.

    Xu, Xiao-Yong; Hu, Zhi-Yong; Li, Jun-Feng; Liu, Ji-Hong; Deng, Xiu-Xin


    In the present paper, attempts were made to explore the possibility of employing ultraviolet (UV) irradiation in citrus asymmetric fusion for transfer of limited amount of favorable traits from a desirable cultivar to a target one. Exposure of Satsuma mandarin (Citrus unshiu Marc.) embryogenic protoplasts to UV at an intensity of 300 muW cm(-2) led to reduced viability, especially under long irradiation duration. The protoplasts could not grow during culture when they were irradiated for over 30 s. Terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) assay revealed extensive DNA fragmentation in the UV-irradiated protoplasts compared with those without UV treatment. Electrofusion between UV-irradiated protoplasts of Satsuma mandarin (donor) with those of Jincheng (C. sinensis Osbeck, recipient), a local cultivar of superior quality, gave rise to regeneration of several lines of shoots, which failed to root despite enormous endeavors. Ploidy analysis via flow cytometry and chromosome counting showed that four selected shoots were either diploid, triploid or tetraploid. Random amplified polymorphism DNA (RAPD) and amplified fragment length polymorphism (AFLP) confirmed the shoots, irrespective of their ploidy level, as putative somatic hybrids. Cleaved amplified polymorphism sequences (CAPS) demonstrated that the shoots predominantly got their cytoplasmic components, in terms of chloroplast (cp) and mitochondrion DNA, from Jincheng, along with possible recombination of cpDNA in some shoot lines. The current data indicated that UV-based asymmetric fusion could also be employed in citrus somatic hybridization with the intention of creating novel germplasms, which may provide an alternative approach for cultivar improvement.

  8. Establishment of high frequency shoot regeneration system in Himalayan poplar (Populus ciliata Wall. ex Royle) from petiole explants using Thidiazuron cytokinin as plant growth regulator

    G Aggarwal; A Gaur; D K Srivastava


    Populus species are important resources for industry and in scientific study on biological and agricul-tural systems. Our objective was to enhance the frequency of plant regeneration in Himalayan poplar (Populus ciliata wall. ex Royle). The effect of TDZ alone and in combi-nation with adenine and NAA was studied on the regen-eration potential of petiole explants. The explants were excised from Himalayan poplar plants grown in glass-houses. After surface sterilization the explants were cul-tured on shoot induction medium. High percentage shoot regeneration (86%) was recorded on MS medium sup-plemented with 0.004 mg L-1 TDZ and 79.7 mg L-1 adenine. The regenerated shoots for elongation and multi-plication were transferred to MS ? 0.5 mg L-1 BAP ? 0.2 mg L-1 IAA ? 0.3 mg L-1 GA3. Root re-generation from shoots developed in vitro was observed on MS medium supplemented with 0.10 mg L-1 IBA. Hi-malayan poplar plantlets could be produced within 2 months after acclimatization in a sterile mixture of sand and soil. We developed a high efficiency plant regeneration protocol from petiole explants of P. ciliata.

  9. Adventitious shoot regeneration of Platanus acerifolia Willd.facilitated by Timentin, an antibiotic for suppression of Agrobacterium tumefaciens in genetic transformation

    Li Zhi-neng; Liu Guo-feng; Fang Fang; Bao Man-zhu


    The effects of Timentin and cefotaxime (Cef) on shoot regeneration of the London plane tree (Platanus acerifolia Willd.) and their use for the suppression of Agrobacterium tumefaciens in Agrobacterium-mediated genetic transformation were compared.Shoot regeneration was significantly reduced on the media with Cef at concentrations from 100 to 500 mg·L-1. Timentin showed negative effect on plant regeneration at concentrations of 100 and 500 mg·L-1; however, 300 mg·L-1 Timentin was shown to facilitate shoot regeneration significantly and the regeneration frequency increased from 64% (control) to 88%. Effective suppression of A.tumefaciens could be obtained with 500 mg·L-1 Cef, but plant regeneration was completely inhibited at this level. The A. tumefaciens on infected P. acerifolia leaf tissues was visually undetectable after three subcultures on a medium with 300 mg·L-1 Timentin. Considering the effect of Cef and Timentin on plant regeneration and suppression of Agrobacteria, Timentin at 300 mg·L-1 is the preferred application in A. tumefaciens-mediated transformation of P.acerifolia.

  10. The features of shoots regeneration of European forsythia (Forsythia europaea Degen et Bald. in sterile culture

    Andrei V. Konstantinov


    Full Text Available The effects of several factors such as medium, the source of cutting material and plant growth regulators concentration on in vitro culture and rapid propagation of Forsythia europaea were investigated. The buds from middle part of shoots sprouted in spring were the optimum type of explants, because of the highest shoot growth rate during initiation procedure and biggest amount of formed shoots per microcutting during subsequent multiplication. The best medium during initiation was WPM supplemented with 0.5 mg·l-1 6-BAP and 0.5 mg·l-1 NAA. Multiplication coefficient was up to 4.8±0,9 on MS medium supplemented with 0.5 mg·l-1 6-BAP at. Shoots were rooted on the WPM medium without growth regulators and the rate of rooting was 71-84%. The microplants obtained transferred to acclimatization substrate (mixture of peat, sand and perlite in proportions 3:1:2 with up to 96% survival.

  11. Rhizobium radiobacter conjugation and callus-independent shoot regeneration used to introduce the cercosporin export gene cfp from Cercospora into sugar beet (Beta vulgaris L.).

    Kuykendall, L David; Stockett, Tammy M; Saunders, Joseph W


    Leaf spot disease caused by Cercospora is responsible for crop and profitability losses in sugar beet crops in the US and worldwide. The cfp gene that encodes a protein that exports phytotoxic cercosporins from Cercospora was conjugally transferred to sugar beet using Rhizobium radiobacter (Agrobacterium tumefaciens), to improve Cercospora-induced leafspot resistance. Conditions for shoot regeneration were optimized to increase regeneration/transformation efficiencies. Low-light and room-temperature conditions were favorable to sugar beet regeneration without callus when cytokinin had been added to the tissue culture medium. Using this procedure adventitious shoots from leaf pieces were obtained in a simple, one-step regeneration procedure. T7, a cfp-transgenic clone verified by PCR with gene-specific primers, is being propagated for leaf spot disease resistance evaluation.

  12. Regeneration of multiple shoots from transgenic potato events facilitates the recovery of phenotypically normal lines: assessing a cry9Aa2 gene conferring insect resistance

    Jacobs Jeanne ME


    Full Text Available Abstract Background The recovery of high performing transgenic lines in clonal crops is limited by the occurrence of somaclonal variation during the tissue culture phase of transformation. This is usually circumvented by developing large populations of transgenic lines, each derived from the first shoot to regenerate from each transformation event. This study investigates a new strategy of assessing multiple shoots independently regenerated from different transformed cell colonies of potato (Solanum tuberosum L.. Results A modified cry9Aa2 gene, under the transcriptional control of the CaMV 35S promoter, was transformed into four potato cultivars using Agrobacterium-mediated gene transfer using a nptII gene conferring kanamycin resistance as a selectable marker gene. Following gene transfer, 291 transgenic lines were grown in greenhouse experiments to assess somaclonal variation and resistance to potato tuber moth (PTM, Phthorimaea operculella (Zeller. Independently regenerated lines were recovered from many transformed cell colonies and Southern analysis confirmed whether they were derived from the same transformed cell. Multiple lines regenerated from the same transformed cell exhibited a similar response to PTM, but frequently exhibited a markedly different spectrum of somaclonal variation. Conclusions A new strategy for the genetic improvement of clonal crops involves the regeneration and evaluation of multiple shoots from each transformation event to facilitate the recovery of phenotypically normal transgenic lines. Most importantly, regenerated lines exhibiting the phenotypic appearance most similar to the parental cultivar are not necessarily derived from the first shoot regenerated from a transformed cell colony, but can frequently be a later regeneration event.

  13. Effects of N(6)-benzylaminopurine and Indole Acetic Acid on In Vitro Shoot Multiplication, Nodule-like Meristem Proliferation and Plant Regeneration of Malaysian Bananas (Musa spp.).

    Sipen, Philip; Davey, Michael R


    Different concentrations of N(6)-benzylaminopurine (BAP) and indole acetic acid (IAA) in Murashige and Skoog based medium were assessed for their effects on shoot multiplication, nodule-like meristem proliferation and plant regeneration of the Malaysian banana cultivars Pisang Mas, Pisang Nangka, Pisang Berangan and Pisang Awak. BAP at 1-14 mg L(-1) with or without 0.2 mg L(-1) IAA, or BAP at 7-14 mg L(-1) with the same concentration of IAA, was evaluated for shoot multiplication from shoot tips and the proliferation of nodule-like meristems from scalps, respectively. Plant regeneration from scalps was assessed using 1 mg L(-1) BAP and 0.2 mg L(-1) IAA separately, or a combination of these two growth regulators. Data on shoot multiplication, the proliferation of nodule-like meristems with associated plant regeneration were recorded after 30 days of culture. A maximum of 5 shoots per original shoot tip was achieved on medium supplemented with BAP at 5 mg L(-1) (Pisang Nangka), 6 mg L(-1) (Pisang Mas and Pisang Berangan), or 7 mg L(-1) (Pisang Awak), with 0.2 mg L(-1) IAA. BAP at 11 mg L(-1) with 0.2 mg L(-1) IAA induced the most highly proliferating nodule-like meristems in the four banana cultivars. Plant regeneration from scalps was optimum in all cases on medium containing 1 mg L(-1) BAP and 0.2 mg L(-1) IAA. This is the first report on the successful induction of highly proliferating nodule-like meristems and plant regeneration from scalps of the Malaysian banana cultivars Pisang Mas, Pisang Nangka, Pisang Berangan and Pisang Awak.

  14. A fasciclin-like arabinogalactan-protein (FLA mutant of Arabidopsis thaliana, fla1, shows defects in shoot regeneration.

    Kim L Johnson

    Full Text Available BACKGROUND: The fasciclin-like arabinogalactan-proteins (FLAs are an enigmatic class of 21 members within the larger family of arabinogalactan-proteins (AGPs in Arabidopsis thaliana. Located at the cell surface, in the cell wall/plasma membrane, they are implicated in many developmental roles yet their function remains largely undefined. Fasciclin (FAS domains are putative cell-adhesion domains found in extracellular matrix proteins of organisms from all kingdoms, but the juxtaposition of FAS domains with highly glycosylated AGP domains is unique to plants. Recent studies have started to elucidate the role of FLAs in Arabidopsis development. FLAs containing a single FAS domain are important for the integrity and elasticity of the plant cell wall matrix (FLA11 and FLA12 and FLA3 is involved in microspore development. FLA4/SOS5 with two FAS domains and two AGP domains has a role in maintaining proper cell expansion under salt stressed conditions. The role of other FLAs remains to be uncovered. METHOD/PRINCIPAL FINDINGS: Here we describe the characterisation of a T-DNA insertion mutant in the FLA1 gene (At5g55730. Under standard growth conditions fla1-1 mutants have no obvious phenotype. Based on gene expression studies, a putative role for FLA1 in callus induction was investigated and revealed that fla1-1 has a reduced ability to regenerate shoots in an in vitro shoot-induction assay. Analysis of FLA1p:GUS reporter lines show that FLA1 is expressed in several tissues including stomata, trichomes, the vasculature of leaves, the primary root tip and in lateral roots near the junction of the primary root. CONCLUSION: The results of the developmental expression of FLA1 and characterisation of the fla1 mutant support a role for FLA1 in the early events of lateral root development and shoot development in tissue culture, prior to cell-type specification.

  15. In vitro shoot regeneration from leaf mesophyll protoplasts of hybrid poplar (Populus nigra x P. maximowiczii).

    Park, Y G; Son, S H


    Protoplasts were isolated from leaf mesophyll of hybrid poplar (Populus nigra X P. maximowiczii) with a mean yield of 10.4 x 10(6) protoplasts per g fresh weight using 2.0% Cellulase 'Onozuka' R-10, 0.8% Macerozyme R-10, 1.2% Hemicellulase, 2.0% Driselase, and 0.05% Pectolyase Y-23 with CPW salts solution containing 0.6 M mannitol, 0.002 M DTT, 3 mM MES at pH 5.6. A liquid plating method produced the highest frequency of dividing protoplasts (48.6%) using an MS medium without NH4NO3. The highest percent of colony formation was 22.8%, produced with fabric supported semi-solid (0.5% w/v) agar plating method using the same culture medium. Growing cell colonies and/or micro-calli were transferred to a fresh semisolid agar medium containing 0.44 μM BAP and 9.0 μM 2,4-D. Multiple shoots were produced from protoplast-derived callus after culture on MS medium containing 6.8 μM zeatin. After root induction on half-strength MS medium that lacked growth regulators, shoots were transferred to pots containing artificial soil mix.

  16. In vitro direct shoot regeneration from proximal, middle and distal segment of Coleus forskohlii leaf explants

    Krishna, Gaurav; P. Sairam Reddy; Anoop Nair, N.; P. W. Ramteke; Bhattacharya, P. S.


    Coleus forskohlii is an endangered multipurpose medicinal plant that has widespread applications. In spite of this, there have been few attempts to propagate its cultivation in India. The present communication presents an in vitro rapid regeneration method using leaf explants of Coleus forskohlii through direct organogenesis. Leaf explants that were excised into three different segments i.e. proximal (P), middle (M) and distal (D) were cultured on Murashige and Skoog (MS) basal medium supplem...

  17. Machine vision based evaluation of impact of light emitting diodes (LEDs) on shoot regeneration and the effect of spectral quality on phenolic content and antioxidant capacity in Swertia chirata.

    Dutta Gupta, S; Karmakar, A


    The present study demonstrates the influence of LED irradiance of various wavelengths on shoot regeneration, biomass accumulation, photosynthetic pigment contents, and antioxidant potentials of Swertia chirata - a critically endangered medicinal plant. Mixed treatment of blue (BL) and red LEDs (RL) in equal proportion (1:1) significantly improved the shoot regeneration response. A machine vision system was developed to assess the shoot regeneration potential under different lighting treatments. Regenerated shoots exposed under BL:RL (1:1) exhibited higher biomass accumulation and canopy development compared to other lighting treatments. Improved canopy growth was evident from the increase in the area, major axis, minor axis, convex area, equivalent diameter and perimeter of regenerated shoot clusters. A higher correlation of dry weight (DW) was noted with the image feature, weighted density (WD) than the fresh weight (FW) in all the LED treated cultures. The significant correlation between DW and WD implies that the image feature WD can be adopted as a non-invasive approach for measuring biomass accumulation as well as detecting hyperhydricity. The developed machine vision approach provides a new direction in the evaluation of shoot organogenesis that displayed features including both shoot multiplication and canopy development. Chlorophyll and carotenoid contents of the regenerated shoots were found to be higher under BL:RL (1:1) than the other treatments. Supplementation of RL led to a reduction in the pigment contents. Spectral quality of lights also significantly influenced the accumulation of total phenolics, flavonoids and flavonols. Cultures exposed under BL exhibited the maximum accumulation of polyphenols. A similar effect of spectral quality was observed with the antioxidant capacity and reducing power potential of leaf extract. The findings demonstrate the ability of LEDs in inducing shoot regeneration as well as accumulation of phenolic antioxidants and

  18. Zebrafish Müller glia-derived progenitors are multipotent, exhibit proliferative biases and regenerate excess neurons

    Powell, Curtis; Cornblath, Eli; Elsaeidi, Fairouz; Wan, Jin; Goldman, Daniel


    ...) that respond to injury by reprogramming and adopting retinal stem cell properties. These reprogrammed MG divide to produce a proliferating population of retinal progenitors that migrate to areas of retinal damage and regenerate lost neurons...

  19. Zebrafish Müller glia-derived progenitors are multipotent, exhibit proliferative biases and regenerate excess neurons

    Curtis Powell; Eli Cornblath; Fairouz Elsaeidi; Jin Wan; Daniel Goldman


    Unlike mammals, zebrafish can regenerate a damaged retina. Key to this regenerative response are Müller glia (MG) that respond to injury by reprogramming and adopting retinal stem cell properties. These reprogrammed MG divide to produce a proliferating population of retinal progenitors that migrate to areas of retinal damage and regenerate lost neurons. Previous studies have suggested that MG-derived progenitors may be biased to produce that are lost with injury. Here we investigated MG multi...

  20. 大叶黄杨无芽茎段不定芽再生及其起源%Regenerating and Origin of Adventitious Shoots from Inter-Node Explants of Euonymus japonicus in vitro

    王茂良; 任桂芳; 王建红; 冯慧; 赵梁军


    In order to improve the resistance of Euonymus japonicus, its ability of adventitious shoots regenerating from internode stem-segment were researched on MS medium in vitro. The effect of both plant growth regulators and carbon resources in media on adventitious shoots differentiating was studied. Regenerating system of E. japonicus was established successfully.Adventitious shoots were highly obtained from inter-node explants inoculated on MS media supplemented with 6-BA 1.7 mg·L-1+ IBA 0.005 mg·L-1 or 6-BA 1.9 mg·L-1 + IBA 0.03 mg·L-1. The regenerating ratio reached to 52.4% and 46.7% respectively. Media for inducing adventitious roots were I/2MS + IAA 0.5 mg·L-1. Adventitious shoots originated from surface tissue of inter-node stem-segment.

  1. Isatin as an auxin source favoring floral and vegetative shoot regeneration from calli produced by thin layer explants of tomato pedicel

    Applewhite, P. B.; K-Sawhney, R.; Galston, A. W.


    Thin layer explants taken from the pedicels and peduncles of flowering tomato plants yielded calli with great organogenetic potential. Of the 15 cultivars tested, 7 regenerated roots, shoots and eventually entire fruit-bearing plants. Calli grown on modified Murashige-Skoog medium responded to varied auxins and cytokinins with different morphogenetic patterns. Thus, naphthaleneacetic acid yielded root-producing calli, while the auxin precursor isatin (indole 2,3-dione) caused the production of calli with vegetative and floral shoots, rarely yielding roots. This may be related to isatin's slow, steady conversion to an active auxin (Plant Physiol 41:1485-1488, 1966) in contrast with naphthaleneacetic acid's immediate presentation of a high level of active auxin. The highest incidence of vegetative shoot (100%) and flower (50%) formation was obtained with 10 micromoles isatin and 3 micromoles zeatin. A few of the flowers developed into ripe fruits. The high frequency of induction of vegetative shoots and flowers before roots with isatin suggests its utility in micropropagation from plant tissue cultures.

  2. The desert moss Pterygoneurum lamellatum (Pottiaceae) exhibits an inducible ecological strategy of desiccation tolerance: effects of rate of drying on shoot damage and regeneration.

    Stark, Lloyd R; Greenwood, Joshua L; Brinda, John C; Oliver, Melvin J


    Bryophytes include clades that incorporate constitutive desiccation tolerance, especially terrestrial species. Here we test the hypothesis that the opposing ecological strategy of desiccation tolerance, inducibility, is present in a desert moss, and address this hypothesis by varying rates of drying in a laboratory study. Desiccation tolerance is arguably the most important evolutionary innovation relevant to the colonization of land by plants; increased understanding of the ecological drivers of this trait will eventually illuminate the responsible mechanisms and ultimately open doors to the potential for the application of this trait in cultivated plants. Plants were cloned, grown in continuous culture (dehardened) for several months, and subjected to rates of drying (drying times) ranging from 30 min to 53 h, rehydrated and tested for recovery using chlorophyll fluorescence, leaf damage, and regeneration of protonema and shoots. Rate of drying significantly affected all recovery responses, with very rapid drying rates severely damaging the entire shoot except the shoot apex and resulting in slower growth rates, fewer regenerative shoots produced, and a compromised photosynthetic system as inferred from fluorescence parameters. For the first time, a desert moss is shown to exhibit an ecological strategy of desiccation tolerance that is inducible, challenging the assumption that arid-land bryophytes rely exclusively on constitutive protection. Results indicate that previous considerations defining a slow-dry event in bryophytes need reevaluation, and that the ecological strategy of inducible desiccation tolerance is probably more common than currently understood among terrestrial bryophytes.

  3. A comparative study on rooting of in vitro regenerated shoots in haploid, diploid and tetraploid purple coneflower (Echinacea purpurea L.

    Rong Chen


    Full Text Available Haploid, diploid and tetraploid shoots of Echinacea purpurea L. sharing the same genome were cultured in medium and their rooting response to the composition of the culture medium was investigated. It was found that in medium without growth regulators, haploid shoots could initiate roots quite efficiently with the shortest time required for the emergence of roots and with the highest rooting rate; the response of the diploids was similar to that of the haploids and largely different from that of the tetraploids. The tetraploids obviously required longer time for the initiation of roots and had the lowest rooting rate. Supplementing the medium with 0.05 and 0.15 mg/L naphthaleneacetic acid or 0.1 and 0.3 mg/L indole-3-butyric acid (IBA had little positive effect on the rooting of diploid shoots and, in some cases, had even negative effect on the rooting of haploid shoots, but enhanced effectively the rooting of the tetraploid shoots. By supplementing the medium with 0.3 mg/L IBA, the time required for the emergence of roots from the tetraploid shoots was shortened and the rooting rate was increased largely. As a result, healthy tetraploid plantlets with fully developed root system could be efficiently propagated.

  4. Uniform Design for Optimizating Regeneration Shoots Directly from Tender Leaves and Plant Regeneration System of Rhododendron chrysanthum Pall.%基于均匀设计优化牛皮杜鹃嫩叶直接再生芽苗及植株再生体系

    李玉梅; 姜云天; 孙智慧


    [Objective] The experimental was aimed to screen the optimum regeneration shoot induction media and rooting media for tender leaves of Rhododendron chrysanthum Pall.[Method] The tender leaves of Rhododendron chrysanthum Pall were taken as explants to select the optimum bud induction media and rooting media through uniform design and the screening results were verified.[Result] The optimum media for regeneration shoot of Rhododendron chrysanthum Pall contained 1/4 MS,3.70 mg/L ZT, 0.02 mg/L IAA and 1.00 mg/L KT and its induction rate was 95.5% and the rooting media contained modified MS, 0.10 mg/L IAA and 0.07 mg/L NAA and its rooting rate was 98%. [Conclusion] Through this experiment, regeneration systems for regeneration shoot and regenerated plant from tender leaves of Rhododendron chrysanthum Pall were created successfully.

  5. 川芎高频再生体系的建立%Establishment and Optimization of High-frequency Shoot Regeneration System of Ligusticum chuanxiong Hort.

    朱玲玲; 梅兰菊; 唐琳


    We explored optimized induction and differentiation medium and culture conditions to establish a protocol of rapid clonal propagation of Ligusticum chuanxiong Hort. The petioles were the best explant and Murashige and Skoog (MS) medium containing 2.0 mg/L KT and 0. 5 mg/L IAA was suitable for high-frequency shoot regeneration. The results suggested that callus were induced from petioles of aseptic seedlings in dark conditions. And then these callus were subcuttured for 15 days in light conditions,about 44.4% frequency of shoot regeneration was induced. The rooting percentage of the regenerated shoots reached 90% on 1/2 MS supplemented with 0.5 mg/L NAA and 0. 5 mg/L IBA. Approximately 95% rooted shoots survived in a greenhouse.%为建立川芎(Ligusticum chuanxiong Hort.)高频再生体系,优化了诱导和分化培养基及培养条件.以叶柄为外植体,以MS为基本培养基,KT2.0 mg/L+ IAA0.5mg/L的激素组合对不定芽分化最有利.在此基础上,针对外植体来源、培养条件和愈伤组织继代时间3个因素进行优化.结果表明:采用川芎无菌苗叶柄作为外植体,黑暗条件下诱导出愈伤组织,再在光照下继代培养15d后转入分化培养基中对不定芽诱导最为有利,分化率为44.4%.分化后得到的不定芽在含NAA0.5 mg/L和IBA 0.5 mg/L的1/2MS培养基上生根率达90%,移栽存活率为95%.

  6. Response of Syngonium podophyllum L. ‘White Butterfly’ shoot cultures to alternative media additives and gelling agents, and flow cytometric analysis of regenerants



    Full Text Available Abstract. Teixeira da Silva JA. 2015. Response of Syngonium podophyllum L. ‘White Butterfly’ shoot cultures to alternative media additives and gelling agents, and flow cytometric analysis of regenerants. Nusantara Bioscience 7: 26-32. Syngonium podophyllum L. (arrowhead vine is a popular leafy indoor pot plant whose tissue culture has been established, primarily through in vitro shoot culture, but several interesting aspects have not yet been explored. In this study, cv. ‘White Butterfly’ was used to investigate the response of shoot formation to alternative gelling agents and media additives. Gellan gum (Gelrite® at 2 g/L resulted in greater leaf production, plantlet fresh weight and higher chlorophyll content (SPAD value than all other gelling agents tested, including agar, Bacto agar, phytagel, oatmeal agar, potato dextrose agar, barley starch and corn starch, when on a basal Hyponex® (NPK = 6.5: 6: 19; 3 g/L medium. Several alternative liquid medium additives tested (low and full fat milk, Coca-Cola®, coffee, Japanese green, Oolong and Darjeeling teas negatively impacted plant growth, stunted roots and decreased chlorophyll content (SPAD value of leaves. Plant growth on medium with refined sucrose or table sugar responded similarly. Poor growth was observed when crude extract from a high rebaudioside-containing stevia (Stevia rebaudiana Bertoni line - an artificial sweetener - was used. Leaf tissue from the control did not show any endopolyploidy but low levels of endopolyploidy (8C were detected in some treatments.

  7. Efficient genetic transformation of Lotus corniculatus L. using a direct shoot regeneration protocol, stepwise hygromycin B selection, and a super-binary Agrobacterium tumefaciens vector

    Nikolić Radomirka


    Full Text Available Cotyledons from 6-day-old Lotus corniculatus cv. Bokor seedlings, transversally cut into two halves, were capa­ble of regenerating buds without intervening callus formation. The explants were co-cultivated with the Agrobacterium tumefaciens LBA4404/pTOK233 superbinary vector carrying the uidA-intron gene and the genes hpt and nptII. They were cultured for 14 days on a regeneration medium, then subjected to a stepwise hygromycin B selection procedure consisting of gradually increasing antibiotic concentrations (5-15 mg L-1 over 21 weeks. Transformed shoots were obtained within 5 months after co-cultivation. Out of 124 initially co-cultivated explants, 52 (42% plants survived hygromycin B selection. The presence of transgenes in regenerated plants was verified by β-glucuronidase histochemical assays and PCR analysis for the presence of uidA gene sequences. Hygromycin B-resistant and PCR-positive T0 plants were cultured in the greenhouse to produce flowers and seeds. The obtained data demonstrate that the reported transformation protocol could be useful for introducing agriculturally important genes into the new L. corniculatus cultivar Bokor.

  8. An efficient and reproducible indirect shoot regeneration from female leaf explants of Simmondsia chinensis, a liquid-wax producing shrub.

    Bala, Raman; Beniwal, Vijay Singh; Laura, Jitender Singh


    Simmondsia chinensis (Link) Schneider is a perennial, dioecious, drought resistant and multipurpose seed oil crop grown in arid and semi-arid conditions throughout the world. A reproducible and more efficient method for indirect shoot organogenesis from female leaf explants has been standardized. The leaf explants cultured on Murashige and Skoog (MS) medium with 1.0 mg l(-1) 2,4-dichlorophenoxyacetic acid (2,4-D) alone produced the highest frequency of callus compared with 1.5 mg l(-1) IBA. Maximum proliferation of callus was observed on MS medium containing a combination of 1.0 mg l(-1) 2,4-D with 0.5 mg l(-1) BAP. For shoot differentiation, the proliferated callus was subcultured on MS medium supplemented with 6-benzylaminopurine (BAP) (1.0-4.0 mg l(-1)) along with 40 mg l(-1) adenine sulphate as additive or in combination with α-naphthalene acetic acid (NAA) or Indole-3-butyric acid (IBA). Optimum shoots differentiated from callus was obtained on MS medium supplemented with 2.0 mg l(-1) BAP and 0.2 mg l(-1) NAA. On this medium, 100 % cultures were responded with an average number of 14.44 shoots per explant with their mean length of 4.78 cm. In vitro rooting (6.22 roots per explant) was achieved on half strength MS medium containing 2 % sucrose with 3.0 mg l(-1) IBA and 300 mg l(-1) activated charcoal (AC). Rooted plantlets were successfully hardened under control conditions and acclimatized under field conditions with 90 % success rate. The present protocol is highly efficient, reproducible and economically viable for large scale production of female plants.

  9. The effects of gamma-ray irradiation to strawberry (Fragaria x ananassa Duch.) calli on shoot regeneration, achene formation and morphological variations of regenerants

    Kasumi, Masakazu [Plant Biotechnology Inst., Ibaraki Agricultural Center, Iwama, Ibaraki (Japan)


    Strawberry (Fragaria x ananassa 'Nyoho') calli, derived from anthers, were irradiated with gamma -ray at dosages from 100 to 1,600 Gy (10 Gy {center_dot} hr{sup -}1) and their effects on callus growth, plant regeneration, and somaclonal variation were analyzed. The growth of callus and percentage of plant regeneration from the callus were reduced slightly at dosages less than 200 Gy, moderately at 400 Gy, and markedly above 800 Gy. Fruit growth associated with seed fertility (>50 % ) was morphologically normal at less than 100 Gy, whereas achene formation was significantly inhibited above 200 Gy. The percentages of morphological variation in regenerants formed from the irradiated callus were:13.7 (no irradiation), 18.6 (100 Gy), 66.0 (200 Gy), 75.7 (400 Gy), and 97.0 (800 Gy). Furthermore, higher dosages yielded wider variations, e.g., thick and small leaf, light leaf color, white flesh, and long fruit. In some regenerants, more than one morphological aberrations developed, some of which were transmissible to daughter plants. These results revealed that the irradiating strawberry callus with gamma - ray resulted in a higher degree and wider spectrum of somaclonal variation than did simple callus culture. (author)

  10. Shoot regeneration from stem and leaf explant of Dendrathema grandiflorum%菊花茎叶外植体再生体系的研究

    高亦珂; 丁国勋; 张启翔; 赵勃


    Adventitious shoots were regenerated from leaf and stem explantsof three chrysanthemum cultivars. The optimum medium for both explant types in ‘Aihuang’ and ‘Yulong’ containd Murashige & Skoog basal medium supplemented with NAA 0.1mg/L+6-BA 1mg/L and NAA 0.2mg/L+6-BA 2mg/L, in ‘Jinbei Dahong’ contained Murashige & Skoog basal medium supplemented with NAA 1mg/L+6-BA 5mg/L. Generally, stem explants were superior to leaf explants. There were large cultivar difference in shoot regeneration frequency with three cultivars failing to respond over a wide range of hormone combination.%以地被菊‘矮黄’、‘玉龙’和传统菊花‘金背大红’的叶盘和茎段为外植体进行再生培养.实验结果表明,不同品种对相同激素水平的反应是不同的:传统的大菊‘金背大红’的愈伤诱导率和分化率都远远低于两种地被菊;在相同条件下以茎段为外植体诱导愈伤率高于叶盘,但是叶盘的直接分化率高于茎段.‘玉龙’和‘矮黄’的最适再生培养基组成为MS+NAA0.1mg/L+6-BA1mg/L和MS+NAA0.2mg/L+6-BA2mg/L,‘金背大红’为MS+NAA1mg/L+6-BA5mg/L.

  11. Improvement of micropropagation protocol of Phalaenopsis sp. for the method of direct shoot regeneration from nodes of floral spikes

    Marković Marija


    Full Text Available This paper succesfully investigated the possibility of modification of the micropropagation protocol of Phalaenopsis sp. with an aim to simplify the procedure and reduce the costs. The obtained results show that some medium components can be succesfully omitted (coconut water, glutamine, 2-morpholinoethanesulfonic acid and some of them (peptone can be replaced with a cheaper constituent (soy flour while preserving the quality of the obtained microplants. The multiplication rate was 7,6 shoots per explant after the period of 150 days of cultivation in vitro. On the same medium 60% of explants were rooted and roots were mostly well developed.

  12. 花曲柳茎芽增殖和植株再生%Shoot multiplication and plant regeneration in Fraxinus rhynchophylla Hance

    单琳; 杨玲; 沈海龙


    In order to establish a high frequency system of tissue culture and plant regeneration in Fraxinus rhynchophylla, taking adventitious stem segments with buds induced from dormant bud and seedling in F. Rhynchophylla as explants, the optimal nutrient media and different combinations of plant growth regulators were selected out, multiple shoots were induced and regenerated plants were obtained. The results showed that April was superior to other periods for collecting dormant buds. The proliferation coefficient of shoots from dormant bud was 2.32 in improved B5 medium supplemented with 4 mg · L-1 BA and 0.10 mg · L-1 IBA, and the proliferation coefficient of shoots from aseptic seedling in the same medium was over 3.0, so the medium was optimal. Rooting rate of shoot could reach 95% in 1/2MS medium supplemented with 0.5 mg · L-1' NAA, so it was optimal medium for rooting. Survival rate of the established plantlets could reach 92% after transferring to growing medium with composition of 50% peat moss, 40% vermiculite and 10% polite. Shoot could root after quickly dipping in 200 g · L"' IBA, and survival rate could reach 60% in the same medium.%为建立高效的花曲柳组培快繁体系,以花曲柳休眠芽萌发获得的带芽茎段和成熟种子无菌萌发获得的带芽茎段为外植体,通过基本培养基和不同植物生长调节剂组合的筛选,诱导出丛生芽,获得了再生植株.结果表明:花曲柳休眠芽采集的最适时期是4月中旬,适合的基本培养基为改良的B5培养基,在改良的B5培养基上添加BA 4.0 mg·L-1和IBA 0.10 mg·L-1,茎芽可以实现增殖,增殖系数可达2.3;在相同培养基上,无菌苗茎段的茎芽增殖系数可达3.0以上;最适的试管内生根培养基为添加NAA 0.5 mg·L-1的1/2MS培养基,茎芽的生根率可达95%,再生植株在草炭土、蛭石和珍珠岩体积比5:4:1的栽培基质中移栽成活率为92%.茎芽速蘸IBA 200 g·L-1后在上述栽培基质中试管

  13. Improved shoot regeneration, salinity tolerance and reduced fungal susceptibility in transgenic tobacco constitutively expressing PR-10a gene

    Parinita eAgarwal


    Full Text Available Plants in ecosystems are simultaneously exposed to abiotic and biotic stresses, which restrict plant growth and development. The complex responses to these stresses are largely regulated by plant hormones, which in turn, orchestrate the different biochemical and molecular pathways to manoeuvre stress tolerance. The PR-10 protein family is reported to be involved in defence regulation, stress response and plant growth and development. The JcPR-10a overexpression resulted in increased number of shoot buds in tobacco (Nicotiana tabacum, which could be due to high cytokinin to auxin ratio in the transgenics. The docking analysis shows the binding of three BAP molecules at the active sites of JcPR-10a protein. JcPR-10a transgenics showed enhanced salt tolerance, as was evident by increased germination rate, shoot and root length, relative water content, proline, soluble sugar and amino acid content under salinity. Interestingly, the transgenics also showed enhanced endogenous cytokinin level as compared to WT, which, further increased with salinity. Exposure of gradual salinity resulted in increased stomatal conductance, water use efficiency, photosynthesis rate and reduced transpiration rate. Furthermore, the transgenics also showed enhanced resistance against Macrophomina fungus. Thus, JcPR-10a might be working in co-ordination with cytokinin signalling in mitigating the stress induced damage by regulating different stress signalling pathways, leading to enhanced stress tolerance.

  14. Evaluación morfológica de brotes regenerados de callos de arroz (variedad IACuba-28 resistentes a higromicina Morphological Evaluation of Shoots Regenerated from Hygromycin-Resistant Rice Callus (cv IACuba-28

    Hernández Díaz Carlos Alberto


    Full Text Available Se estableció un sistema de evaluación de brotes de arroz regenerados de callos resistentes a higromicina, que permitió relacionar las características morfológicas de dichos brotes con su resistencia al antibiótico. Callos embriogénicos de arroz se transformaron con Agrobacterium tumefaciens (EHA105/ pCAMBIA1300, con el gen de la higromicina-fosfotransferasa como marcador de selección. Después de dos semanas en medio de cultivo con higromicina, los callos resistentes fueron transferidos a regeneración. Durante 30 días se realizaron extracciones sucesivas de brotes emitidos de los callos, en seis intervalos de cinco días cada uno. Estos brotes se clasificaron según su morfología en: clase I – brote vigoroso con una estructura bipolar típica, de ápice y raíz con longitudes proporcionales; clase II – brote con raíz pequeña respecto al ápice, o sin raíz; clase III – brote con alteraciones fenotípicas, albinismo, hojas muy anchas o enrolladas. Los brotes clasificados se transfirieron a medio MS con higromicina para evaluar su viabilidad. Los de clase I, que predominaron en las primeras extracciones, presentaron la mayor viabilidad durante el enraizamiento y crecimiento del follaje. En las últimas dos extracciones ocurrió una drástica reducción de los brotes clase I, y aumentaron los de clases II y III, simultáneamente disminuyó la viabilidad de estos últimos en MS con higromicina. Este resultado puede aplicarse para mejorar la eficiencia de obtención de plantas transgénicas de arroz en estas condiciones, debido a que precisa el momento óptimo para lograr brotes con características morfológicas normales y que sean resistentes a higromicina.An evaluation system based on the morphological characteristics of regenerated hygromycin-resistant rice callus shoots was established for correlating such characteristics with shoot viability on hygromycin. Embryogenic rice calli were transformed by Agrobacterium tumefaciens

  15. [Proliferative Vitreoretinopathy].

    Wiedemann, P; Bringmann, A


    Proliferative vitreoretinal retinopathy (PVR) is a very severe complication of vitreoretinal surgery. PVR is characterised by a complex cellular reaction. This corresponds to a vitreoretinal wound healing reaction and leads to tractional retinal detachment fixed by membranes. A rational goal of treatment is the removal of active cells and membranes, particularly the whole vitreous body; this can only be achieved surgically.

  16. Influences of Cefotaxime and Carbenicillin on Shoot Regeneration from Soybean Cotyledonary-node%头孢青霉素和羧苄青霉素对大豆子叶节茎再生的影响

    可庆波; 王丽艳; 王艳; 张春涛; 殷奎德


    试验通过向茎诱导培养基和茎伸长培养基中添加不同浓度的头孢青霉素(Cef)和羧苄青霉素(Cb)来研究二者对大豆子叶节茎再生潜在的影响。一定浓度的Cef或Cb对大豆子叶节部位茎的再生有促进或抑制作用。不同基因型大豆的最适Cef或Cb添加浓度不同。培养基中添加100 mg.L-1 Cef或120 mg.L-1 Cb能显著提高垦农18号(K18)子叶节部位丛生芽的诱导及可伸长茎的生成和伸长;150 mg.L-1 Cef对垦农4号(K4)子叶节部位茎的再生有显著的促进作用1,20 mg.L-1 Cb和200 mg.L-1 Cb分别显著提高K4丛生芽的再生和随后可伸长茎的生成及伸长。经121℃高压灭菌处理的Cef和Cb对大豆子叶节部位丛生芽的诱导和可伸长茎的生成及伸长有显著的抑制作用。%The influences of cefotaxime and carbenicillin on shoot regeneration potential of soybean cotyledonary-node were investigated by supplying with various concentrations of cefotaxime and carbenicillin to shoot induction medium and shoot elongation medium.The capability of shoot regeneration from soybean cotyledonary-node could be promoted or suppressed by supplying with some certain concentration of cefotaxime and carbenicillin.However,the most appropriate treatment is genotype-dependent.The buds regeneration,shoot multiplication and elongation of cotyledonary-node of K18 can be enhanced significantly by supplying with 100 mg·L-1 cefotaxime or 120 mg·L-1 carbenicillin in culture medium;the capability of shoot regeneration of K4 could be promoted with 150 mg·L-1 cefotaxime or 120 mg·L-1 carbenicillin on buds regeneration and 200 mg·L-1 on shoot multiplication and elongation.Autoclaved cefotaxime and carbenicillin showed detrimental effects on buds regeneration and shoot multiplication and elongation respectively.

  17. Regeneração in vitro de brotações de Pereira (Pyrus communis L. cultivar Carrick In vitro regeneration of shoots of pear (Pyrus communis L. cv. Carrick

    Alan Cristiano Erig


    Full Text Available O objetivo deste trabalho foi obter um protocolo de regeneração de brotações in vitro a partir de explantes de pereira (Pyrus communis L. cultivar Carrick, visando a programas de transformação genética. Para tanto, utilizaram-se três tipos de explantes (ápice caulinar, folha e entrenó que permaneceram durante 0, 10, 20, 30 ou 40 dias em meio de indução e, posteriormente, foram transferidos para meio de proliferação com 8,9 ou 13,3µM de thidiazuron (TDZ. Aos 85 dias após o início do experimento, observou-se que o explante ápice caulinar apresentou maior capacidade de regeneração de brotações quando comparado ao explante entrenó, enquanto o explante folha não mostrou capacidade de regenerar brotações. Verificou-se também que, inoculando o explante diretamente em meio de proliferação sem auxina, houve uma maior percentagem de regeneração e que, aumentando o tempo de permanência dos explantes em meio de indução, diminuiu a percentagem de regeneração de brotações. A concentração de thidiazuron (TDZ no meio de proliferação não afetou a capacidade de regeneração de brotações.The objective of this work was to obtain a shooting regeneration protocol from explants of pear tree (Pyrus communis L. Carrick cultivar, aiming at genetic transformation programs. Three types of explants (caulinary tip, leaf and entrenode were used. They were left for 0, 10, 20, 30 or 40 days in induction medium, and afterwards they were transferred to proliferation medium with 8.9 or 13.3µM of TDZ. At 85 days after the beginning of the experiment, it was noted that the caulinary tip explant showed higher capacity of shooting regeneration when compared to entrenode explants, while the leaf explant was not able to regenerate. It was also observed that inoculating the explant directly in proliferation medium without auxin resulted in a higher percentage of regeneration, and increasing the period of time that the explants remained in

  18. Pneumatic hydrodynamics influence transplastomic protein yields and biological responses during in vitro shoot regeneration of Nicotiana tabacum callus: Implications for bioprocess routes to plant-made biopharmaceuticals.

    Barretto, Sherwin S; Michoux, Franck; Hellgardt, Klaus; Nixon, Peter J


    Transplastomic plants are capable of high-yield production of recombinant biopharmaceutical proteins. Plant tissue culture combines advantages of agricultural cultivation with the bioprocess consistency associated with suspension culture. Overexpression of recombinant proteins through regeneration of transplastomic Nicotiana tabacum shoots from callus tissue in RITA(®) temporary immersion bioreactors has been previously demonstrated. In this study we investigated the hydrodynamics of periodic pneumatic suspension of liquid medium during temporary immersion culture (4 min aeration every 8 h), and the impact on biological responses and transplastomic expression of fragment C of tetanus toxin (TetC). Biomass was grown under a range of aeration rates for 3, 20 and 40-day durations. Growth, mitochondrial activity (a viability indicator) and TetC protein yields were correlated against the hydrodynamic parameters, shear rate and energy dissipation rate (per kg of medium). A critical aeration rate of 440 ml min(-1) was identified, corresponding to a shear rate of 96.7 s(-1), pneumatic power input of 8.8 mW kg(-1) and initial 20-day pneumatic energy dissipation of 127 J kg(-1), at which significant reductions in biomass accumulation and mitochondrial activity were observed. There was an exponential decline in TetC yields with increasing aeration rates at 40 days, across the entire range of conditions tested. These observations have important implications for the optimisation and scale-up of transplastomic plant tissue culture bioprocesses for biopharmaceutical production.

  19. Multiplicação in vitro de abacaxi ornamental por estiolamento e regeneração de brotações In vitro multiplication of ornamental pineapple by shoot etiolation and regeneration

    Ana Cristina PP de Carvalho


    and total number of nodes/etiolated shoot. For shoot regeneration, nodal segments from in vitro etiolated stems with two nodes were inoculated in the following media: MS without growth regulator; MS + 4.44 µM of 6-benzylaminopurine (BA; MS + 8.88 µM of BA; MS + 13.32 µM of BA. The flasks were incubated under photoperiod of 16 hours, at 25±2ºC. At 30 days of culture, the number of regenerated shoots/explant did not differ in the tested media. At 45 and 60 days of culture, the media with BAP induced higher number of regenerated shoots per node, differing statistically from the control.

  20. 甜樱桃品种吉列玛叶片再生不定梢的研究%Shoot regeneration from leaves of sweet cherry (Prunus avium L.) in vitro

    孙清荣; 李勃; 张力思; 石荫坪


    本培养基NN69或WPM上附加BA和低浓度的NAA,IAA,IBA作培养基,诱导甜樱桃品种吉列玛试管苗的叶片产生了不定梢。以WPM附加BA 3mg/L和IAA0.3mg/L的处理,不定梢再生率最高,为33.3%。%Shoot regenerated from leaves of sweet cherry variety Dilemma in vitro on the media WPM or NN69 supplemented with cytokinin BA and auxin IAA, NAA or IBA. The regeneration ratio accounted for 33.3% when cultured on the medium WPM supplemented with 4mg/L BA and 0.3mg/L IAA.

  1. Shoot Tip Culture of Arnica montana for Micropropagation.

    Conchou, O; Nichterlein, K; Vömel, A


    Multiple shoots were regenerated from shoot tips of ARNICA MONTANA on MS and B5 media supplemented with BA (1 mg/l) and NAA (0.1 mg/l). Sections of 1-2 mm in length cultured from IN VITRO germinated seedlings regenerated 7.7 (mean) shoots on the MS medium, whereas sections cultured from greenhouse plants regenerated 9.0 (mean) shoots on the B5 medium within 6 weeks. Subsequent subcultures of shoots on the same media but without NAA resulted in similar or lower multiplication rates (1.6 to 3.1 in 3 weeks). Shoot development was promoted, whereas shoot initiation was simultaneously inhibited by the addition of activated charcoal to the media. Rooting was induced by culturing shoots from seedling as well as from greenhouse plant shoot tips on MS or B5 medium supplemented with NAA. The plantlets were transplanted into soil and grown successfully under greenhouse and field conditions.

  2. Regeneración de brotes adventicios en hojas de guayaba (Psidium guajava L. cultivadas in vitro Adventitious shoot regeneration from in vitro cultured leaves of guava (Psidium guava L.

    Trujillo Sánchez Reinaldo


    Full Text Available La regeneración de brotes adventicios es una etapa clave para la aplicación de las técnicas de ingeniería gené­tica. El presente trabajo tuvo como objetivo el desarrollo de un procedimiento para la regeneración de brotes por organogénesis a partir de hojas de microesquejes o brotes de guayaba (Psidium guajava L. cultivados in vi­tro. Para ello se estudiaron algunos de los principales factores que afectan la regeneración de brotes, tales como la concentración de reguladores del crecimiento (citoquinina, el estado fisiológico del explante y la he­rida. En todos los experimentos se utilizaron como explantes hojas de vitroplantas de guayaba de la variedad Enana Roja Cubana EEA18-40 de diferentes subcultivos. El mejor resultado se alcanzó con una concentración de 0,75 mg/L de 6-bencilaminopurina como suplemento hormonal del medio MS. Se comprobó que para las hojas provenientes de microesquejes con mayor número de subcultivo y tomadas de la parte inferior de los brotes, el potencial morfogenético disminuye significativamente (p60% y el mayor número de brotes por explante promedio (>3 se alcanzó al realizar varias heridas en forma de punteaduras en el nervio central de las hojas. Este protocolo de regeneración constituye una importante herramienta que puede ser empleada para futuros estudios de transformación genética en esta especie. Palabras clave: cultivo de tejidos, explantes de hoja, reguladores de crecimiento, organogénesis, guayaba.Adventitious regeneration is a key step in the application of genetic engineering to the breeding programs of plants. In this work a method for adventitious shoot regeneration from leaves of micropropagated guava shoots has been developed and some of main factors to affect the shoot regeneration like, concentration of plant growth regulators (citoquinine, physiological state of explants and the wound are studied. Leaves from guava in vitro cultured of variety Cuban Red Dwarf 18-40 was used

  3. Ectopic expression of class 1 KNOX genes induce and adventitious shoot regeneration and alter growth and development of tobacco (Nicotiana tabacum L) and European plum (Prunus domestica L)

    Transgenic plants of tobacco (Nicotiana tabacum L) and plum (Prunus domestica L) were produced by transforming with apple class 1 KNOX genes (MdKN1 and MdKN2) or corn KN1 gene. Transgenic tobacco plants were regenerated in vitro from transformed leaf discs cultured in a tissue medium lacking cytoki...

  4. Initiation of somatic embryos and regeneration of plants from primordial shoots of 10-year-old somatic white spruce and expression profiles of 11 genes followed during the tissue culture process.

    Klimaszewska, Krystyna; Overton, Catherine; Stewart, Don; Rutledge, Robert G


    Adult conifers are notoriously recalcitrant in vegetative propagation and micropropagation that would result in the regeneration of juvenile propagules through somatic embryogenesis (SE) has not been demonstrated to date. Because SE-derived material is more amenable in subsequent tissue culture experiments compared with seed-derived material, a multi-year study was conducted to investigate induction of SE from primordial shoot (PS) explants that were excised from shoot buds of somatic embryo-derived white spruce. The SE induction experiments were carried out first with greenhouse-grown and later with field-grown trees each year from 2002 (2-year-old) to 2010 (10-year-old). Of the four genotypes tested, 893-2 and 893-12 never responded, 893-1 responded up to year 4 and 893-6 consistently responded every year. In 2010, for the first time, three of the 17 893-6 clonal trees produced male strobili as well as SE from cultured PS explants. SE induction was associated with formation of a nodule on the surface of an elongated needle primordium or in callus. Early somatic embryos were detectable after about 3 weeks of culture. Of 11 genes whose expression profiles were followed during the PS cultures, CHAP3A, VP1, WOX2 and SAP2C were expressed exclusively in the early stages of SE, and could potentially be used as markers of embryogenecity. Mature somatic embryos and plants were produced from the explants of responding genotype. Implication of these results for future research on adult conifer recalcitrance in micropropagation is discussed.

  5. Indução de superbrotamento e regeneração de plantas in vitro, nas cultivares de algodão colorido Induction of multiple shoots and regeneration of plants in vitro, in coloured cotton cultivars

    Maria do S. Rocha


    for 20 min. The shoot had been induced, in the explant of cotiledonary nodes in MS medium basic, supplemented with 6-benzylaminopurine (BAP, Cinetina (KIN and Tiadiazuron (TDZ, isolated or associated in different concentrations. The material was kept for 40 days in growth chamber, under controlled ambient conditions. 10 mL of medium was used for treatment with a explant for culture tube, in an entirely randomized design, with factorial arrangement of 4 x 17 (four genotypes x seventeen medium. It was observed that the MS medium supplemented with BAP (2.0 mg L-1 isolated or associated with KIN (1.0 mg L-1, promoted greater capacity of regeneration and height of sprouts; MS medium supplemented with BAP (2.5 mg L-1 stimulated greater height of sprouts and the MS medium supplemented with TDZ (1.0, 0.50 and 0.25 mg L-1 affected the capacity of regeneration of sprouts, a larger formation of calluses was observed.

  6. Tissue Culture and Shoot Regeneration from in Vitro Leaf Explants of Apple Dwarifng Rootstock Cultivar‘JM7’%苹果矮化砧木‘JM7’的组织培养及其离体叶片不定梢再生

    孙洪雁; 孙清荣; 李国田; 张琼; 李芹


    以苹果优良矮化砧木‘JM7’(Malus prunifolia×M. pumila‘Malling 9’)为试材,研究了基本培养基对试管苗增殖生长的影响、蔗糖浓度对试管苗生根的影响及基本培养基、细胞分裂素种类和浓度对离体叶片不定梢再生的影响。结果表明:基本培养基MS比QL显著提高增殖梢数,但QL比MS更有利于获得健壮生长的绿苗。3%蔗糖浓度比2%的不定根发生速度快。叶片不定梢再生最适宜的基本培养基是QL。在QL培养基上,6-BA和TDZ对离体叶片不定梢再生率的影响无显著差异,但6-BA诱导产生的不定芽在不定梢诱导培养基上可直接伸长生长形成不定梢,而TDZ诱导产生的不定芽需转移到不加TDZ而加低浓度6-BA的培养基上形成伸长生长的不定梢。%A good apple dwarifng rootstock cultivar‘JM7’ (Malus prunifolia×M. pumila‘Malling 9’) was se-lected as material. Effects of basal medium on shoot proliferation and sucrose concentration on in vitro rooting were examined. Effects of basal medium, the kinds and the concentration of cytokinin on shoot regeneration from in vitro leaf explants were investigated. Results showed that basal medium MS signiifcantly improved shoot proliferation than that QL, but stronger shoots were obtained on QL than on MS. The concentration of 3%sucrose improved the process of root initiation than that of 2%. The optimal basal medium for shoot regenera-tion from leaf explants was QL. When using QL as basal medium, the effects of TDZ and 6-BA on the percent-age of shoot regeneration didn’t show signiifcant difference. However, adventitious buds from 6-BA were able to directly elongate and develop into shoots on shoot regeneration induction medium (SIM), whereas adventi-tious buds from TDZ was unable to elongate and develop into shoots on SIM, it was necessary to transfer the buds to the medium lacking TDZ but containing low concentration of 6-BA to form shoots.

  7. Shoot production in squash (Cucurbita pepo) by in vitro organogenesis.

    Ananthakrishnan, G; Xia, X; Elman, C; Singer, S; Paris, H S; Gal-On, A; Gaba, V


    Seedling-derived cotyledon explants of squash ( Cucurbita pepo L.) of commercial cultivars True French, Ma'yan and Goldy were regenerated in vitro on Murashige and Skoog medium augmented with 1 mg/l benzyladenine. After 4 weeks in culture small shoots and buds regenerated only on the most proximal cotyledon edge. Culture on an elongation medium with a reduced cytokinin concentration (0.1 mg/l) with or without 1 mg/l gibberellic acid (GA(3)) facilitated the recovery of shoots. Fresh shoots could be recovered at each subculture of the regenerating mass. Peak productivity was during the third cycle of subculture, and shoot production ceased after the fifth subculture. Culture on elongation medium supplemented with GA(3) was 55% more effective with respect to overall shoot production than that on medium without GA(3), with 22 shoots recovered in total per explant from the former. Regeneration occurred under both light and dark conditions. All of the shoots tested were diploid. The shoots were rooted and transferred to the greenhouse where they grew and flowered normally.

  8. Proliferative retinopathy predicts nephropathy

    Karlberg, Charlotte; Falk, Christine; Green, Anders;


    We wanted to examine proliferative retinopathy as a marker of incident nephropathy in a 25-year follow-up study of a population-based cohort of Danish type 1 diabetic patients and to examine cross-sectional associations between nephropathy and retinopathy in long-term surviving patients of the same...... photographs at follow-up. Single spot urine was used to evaluate nephropathy at both examinations. Proliferative retinopathy was present in 29 patients (15.8%) at baseline. At follow-up, these patients were more likely to macroalbuminuria (20.7% vs. 6.5%) than patients without proliferative retinopathy...... at baseline. In a multivariate logistic regression adjusted for baseline age, sex, duration of diabetes, smoking, HbA(1,) systolic and diastolic blood pressure, odds ratio of nephropathy (micro- and macroalbuminuria combined) was 2.98 (95% confidence interval 1.18-7.51, p = 0.02) for patients...

  9. Adventitious shoot formation on leaf cuttings in vivo, a tool in horticulture.

    Custers, J.B.M.


    Adventitious shoot formation implies the regeneration or development of shoots from fully differentiated tissue. Its application has, after the rise of in vitro culture, assumed large proportions. Then the question arose whether in vivo adventitious shoot formation could not be applied more widely i

  10. PkMADS1 is a novel MADS box gene regulating adventitious shoot induction and vegetative shoot development in Paulownia kawakamii.

    Prakash, A Pavan; Kumar, Prakash P


    Direct regeneration of shoot buds in vitro is an important technique in plant genetic manipulation. We describe the isolation and functional characterization of a novel MADS box cDNA (PkMADS1) from Paulownia kawakamii leaf explants undergoing adventitious shoot regeneration. mRNA gel blot analysis confirmed the expression of PkMADS1 in the shoot-forming cultures, but no signal was observed in the callus-forming cultures. PkMADS1 transcripts were also detected in shoot apices, but not in root apices, initial leaf explants or the flower. In situ hybridization revealed that its expression was restricted to developing shoot primordia in the excised leaf cultures, suggesting a role for this gene in adventitious shoot formation. Transgenic Paulownia plants over-expressing the PkMADS1 gene showed some changes in phenotype, such as axillary shoot formation. In the antisense transformants, shoots were stunted and had altered phyllotaxy, and, in some lines, the shoot apical meristem appeared to have been used up early during shoot development. Leaf explants from the antisense transgenic plants showed a tenfold decrease in shoot regeneration compared with explants from sense transformants or wild-type. Our results show that PkMADS1 is a regulator of shoot morphogenesis.

  11. An Efficient Method for Adventitious Shoot Regeneration from Leaf and Stem-segment Explants of Russian Olive Elaeagnus angustifolia L.%采用俄罗斯橄榄叶片和茎段诱导产生不定芽的高效再生方法

    卢松冲; 朱金启; 李杰; 张洪霞


    The establishment of an efficient adventitious shoot regeneration system from leaf discs and stem segments of one-year-old Russian olive ( Elaeagnus angustifolia L. ) was established. Shoot regeneration using leaf explants and stem segments was obtained on MS medium supplemented with different cytokinins viz., 6-benzyladenine (BA) and Zeatin (Zt), with combination of auxins viz. , naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA). MS + 0.5mg/L 6-BA + 0.2mg/L NAA was found to be a better combination for leaf regeneration, producing a maximum of 4.3 shoots per explant, whereas MS + 1. 0mg/L Zt +0.5mg/L NAA for stem-segment explants produced the highest number of multiple shoots (3.6) per explant. The regenerated shoots produced 100% rooting on 1/2 strength MS medium supplied with 0.5mg/L NAA. In vitro raised plantlets were successfully transferred to pots containing sterile soil: peat moss: sand ( 1 : 1 : 1 ) for acclimatization, and 77% of rooted plantlets survived under ex situ conditions. The currently employed regeneration protocol through leaf explants and stem segments facilitates germplasm conservation of this medicinally and ecologically important species besides providing a standardized regeneration protocol for genetic transformation studies in the future.%俄罗斯橄榄(Elaeagnus angustifolia L.)是一种具有很重要药用价值和生态意义的植物.以俄罗斯橄榄一年生幼苗的叶片和茎段为实验材料,探讨了细胞分裂素类(6-BA和Zt)和生长素类(NAA和IBA)两类激素不同组合以及不同配比对植株再生的影响,最后建立了一个高效的俄罗斯橄榄再生方法.结果表明,MS培养基+0.5 mg/L 6-BA+0.2 mg/L NAA更适合叶片的再生,平均每个外植体能产生多达4.3个不定芽;而在MS培养基+1.0 mg/L Zt+0.5 mg/L NAA的条件下,茎段外植体再生出来的不定芽最多可以达到平均3.6个;再生芽在含有0.5 mg/L NAA的1/2 MS培养基上生根率达到100%.体外再生苗移

  12. PLETHORA Genes Control Regeneration by a Two-Step Mechanism.

    Kareem, Abdul; Durgaprasad, Kavya; Sugimoto, Kaoru; Du, Yujuan; Pulianmackal, Ajai J; Trivedi, Zankhana B; Abhayadev, Pazhoor V; Pinon, Violaine; Meyerowitz, Elliot M; Scheres, Ben; Prasad, Kalika


    Regeneration, a remarkable example of developmental plasticity displayed by both plants and animals, involves successive developmental events driven in response to environmental cues. Despite decades of study on the ability of the plant tissues to regenerate a complete fertile shoot system after inductive cues, the mechanisms by which cells acquire pluripotency and subsequently regenerate complete organs remain unknown. Here, we show that three PLETHORA (PLT) genes, PLT3, PLT5, and PLT7, regulate de novo shoot regeneration in Arabidopsis by controlling two distinct developmental events. Cumulative loss of function of these three genes causes the intermediate cell mass, callus, to be incompetent to form shoot progenitors, whereas induction of PLT5 or PLT7 can render shoot regeneration hormone-independent. We further show that PLT3, PLT5, and PLT7 establish pluripotency by activating root stem cell regulators PLT1 and PLT2, as reconstitution of either PLT1 or PLT2 in the plt3; plt5-2; plt7 mutant re-established the competence to regenerate shoot progenitor cells but did not lead to the completion of shoot regeneration. PLT3, PLT5, and PLT7 additionally regulate and require the shoot-promoting factor CUP-SHAPED COTYLEDON2 (CUC2) to complete the shoot-formation program. Our findings uncouple the acquisition of competence to regenerate shoot progenitor cells from completion of shoot formation, indicating a two-step mechanism of de novo shoot regeneration that operates in all tested plant tissues irrespective of their origin. Our studies reveal intermediate developmental phases of regeneration and provide a deeper understanding into the mechanistic basis of regeneration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Protoplast culture and plant regeneration of several species in the genus Dianthus.

    Nakano, M; Mii, M


    Seventeen cultivars belonging to the genus Dianthus were examined for protoplast isolation, culture and shoot regeneration under the same conditions. These included D. caryophyllus, D. chinensis, D. barbatus, D. plumarius, D. superbus and D. japonicus as well as interspecific hybrid cultivars (D. caryophyllus x D. chinensis and D. chinensis x D. barbatus). In all cultivars, viable protoplasts were isolated at high yields from leaves of axenic shoot cultures and some of these protoplasts divided and formed colonies. However, shoot regeneration frequencies were markedly different among the species. High frequency shoot regeneration was obtained from D. chinensis and interspecific hybrid cultivars, while only low frequency or no shoot regeneration was obtained from other species.

  14. Transplantation of Expanded Fetal Intestinal Progenitors Contributes to Colon Regeneration after Injury

    Fordham, Robert P; Yui, Shiro; Hannan, Nicholas R F


    Regeneration and homeostasis in the adult intestinal epithelium is driven by proliferative resident stem cells, whose functional properties during organismal development are largely unknown. Here, we show that human and mouse fetal intestine contains proliferative, immature progenitors, which can...


    A novel plant regeneration protocol was established for castor (Ricinus communis L.), an important oilseed crop. Mature seed-derived cotyledon explants produced adventitious shoots when placed on Murashige and Skoog (MS) medium containing thidiazuron (TDZ). The rate of shoot regeneration was maximal...


    Shaheena Parveen


    Full Text Available A rapid, simple and efficient protocol for direct in vitro multiple shoot induction and plantlet regeneration was achieved from shoot tip explants of Cicer arietinum. The shoot tips were cultured on MS medium fortified with Thidiazuron (TDZ (1.0-7.0 mg/L for multiple shoot induction. Multiple shoots proliferation was best observed at 3.0 mg/L TDZ from the shoot tip explants within three weeks of culture. Shoot number per explant ranged between 2 and 10. Individual shoots were aseptically excised and sub cultured in the same media for shoot elongation. The elongated shoots were transferred to Indole Butyric Acid (IBA (1.0mg/L–5.0mg/L for root induction. Rooting was observed within two weeks of culture. Rooted plantlets were successfully hardened under culture conditions and subsequently established in the field conditions. The recorded survival rate of the plants was 86%. Plants looked healthy with no visually detectable phenotypic variations.

  17. Avaliação da fidelidade genotípica por marcadores RAPDs de brotações de pereira (Pyrus communis L. cv. Carrick, regeneradas in vitro Evaluation of the genotypic fidelity by RAPD markers of pear shoots (Pyrus communis L. cv. Carrick, in vitro regenerated

    Alan Cristiano Erig


    Full Text Available O objetivo deste trabalho foi avaliar a fidelidade genotípica de brotações de pereira (Pyrus communis L. cultivar Carrick, regeneradas in vitro, utilizando marcadores RAPDs. O DNA genômico foi extraído de folhas oriundas das brotações de pereira regeneradas a partir de diferentes tratamentos e de plantas matrizes micropropagadas (planta controle, utilizando-se o protocolo descrito por FERREIRA & GRATTAPAGLIA (1996. Para triagem dos primers foram utilizados os kits OPAN, OPA e OPF (Operon Technologies, Inc. e, destes, foram escolhidos sete primers: OPAN-03, OPAN-14, OPAN-15, OPAN-16, OPA-02, OPA-08 e OPF-04. A separação dos produtos da amplificação foi realizada através de eletroforese horizontal em gel de agarose 1,2%, corado com brometo de etídio. Após a corrida, os géis foram visualizados sobre um transiluminador de luz ultravioleta e fotografados com câmara Polaroid para registro dos dados. A ausência ou adição de uma ou mais bandas comparativamente ao padrão da planta matriz (planta controle foi considerado variação somaclonal. Dos 66 fragmentos produzidos pelos sete primers, observou-se 100% de bandas monomórficas, indicando que nenhum dos primers utilizados detectou variação somaclonal nas brotações regeneradas.The aim of this work was to evaluate the genotypic fidelity of pear shoots (Pyrus communis L. cultivar Carrick regenerated in vitro, using RAPD markers. Genomic DNA was extracted from leaves regenerated from pear shoots submitted to different treatments and from micropropagated matrix plants (control plant, using the protocol descripted by FERREIRA & GRATTAPAGLIA (1996. For primer selection, the Kits OPAN, OPA, and OPF (Operon Technologies, Inc. were used. Seven primers were chosen: OPAN-03, OPAN-14, OPAN-15, OPAN-16, OPA-02, OPA-08 and OPF-04. Amplified products were submitted to horizontal electrophoresis in 1.2% agarose gel, stained with ethidium bromide and visualized under UV light. The result was

  18. Shooting mechanisms in nature

    Sakes, Aimée; Wiel, van der Marleen; Henselmans, Paul W.J.; Leeuwen, van Johan L.; Dodou, Dimitra; Breedveld, Paul


    Background In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these m

  19. Shooting mechanisms in nature

    Sakes, Aimée; Wiel, van der Marleen; Henselmans, Paul W.J.; Leeuwen, van Johan L.; Dodou, Dimitra; Breedveld, Paul


    Background In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these

  20. Shoot dieback in pecan

    Two shoot dieback maladies (SDM) of pecan [Carya illinoinensis (Wangenh.) C. Koch] are of unknown cause and can adversely affect canopy health. They occur during either early spring (SpSDM) or early summer (SuSDM). Field evaluation found that both maladies predominately occur on shoots retaining p...

  1. Plant Regeneration of Sweet Potato via Somatic Embryogenesis from Different Explants

    Ling ZHANG; Hongxuan XU; Baifu QIN; Zhihua LIA0; Min CHEN; Chunxian YANG; Yufan FU; Qitang ZHANG


    [Objective] This study aimed to regenerate plants of sweet potato (Ipomoea batatas) cultivar Xushu22 via somatic embryogenesis, using leaf and shoot apex as explants. [Method] The leaf and shoot apex of Xushu 22 were separately cultured on MSB medium and MSD medium. The induced embryogenic calluses were then cultured on MS medium. The regeneration frequency of leaf and shoot apex ex- plants were respectively calculated. [Result] The average frequency of leaf explants developing somatic callus was 95.69% compared to 30.56% in case of shoot apex explants. There were different types of morphogenic structures in the process of so- matic embryo development. Leaf explants gave a high regeneration frequency to 60.61%, while the regeneration frequency of shoot apices was 22%. In addition, no morphological variations were observed in the regeneration plants. [Conclusion] Leaf explant was better than shoot apices in plant regeneration of Xushu22 via somatic embryogenesis.

  2. Induction and regeneration of adventitious shoot from in vitro leaves of Zizyphus jujuba ' Kongfusucui' plantlet%'孔府酥脆'枣试管苗离体叶片不定梢诱导和再生

    孙清荣; 孙洪雁; 周广芳


    Using in vitro leaves of Zizyphus jujuba ‘ Kongfusucui’ plantlet as explants, effects of culture method,phytohormone proportion and culture time on induction rate of adventitious shoot from leaves and effects of sucrose concentrations in rooting media on rooting of adventitious shoot were studied. The results show that induction rate of adventitious shoot by two-step culture method ( firstly cultured on medium Ⅰ for four weeks then cultured on medium Ⅱ for three weeks) is significantly higher than that by one-step culture method (cultured continuously on medium Ⅰ for seven weeks). Phytohormone proportion in medium Ⅰ has an obviously influence on induction rate of adventitious shoot, which gradually increases with increasing of TDZ concentration in medium Ⅰ . And adding 1.0 mg · L-1 TDZ in medium Ⅰ leads to induction rate with above 80%. With culture time prolonging ( cultured for 1, 2, 3 or 4 weeks on medium Ⅰ ,respectively), induction rate increases gradually. Sucrose concentration has a significant effect on rooting of adventitious shoot, sucrose with higher concentration (30 g · L-1 ) is beneficial to rooting. According to induction rate and growth status of adventitious shoot, it is determined that optimal culture method of adventitious shoot induction from Z. jujuba ‘ Kongfusucui’ leaves is two-step culture method, that is, leaves firstly cultured on WPM medium containing 1.0 mg · L-1 TDZ and 0.5 mg · L-1 IAA for four weeks, and then cultured on WPM medium containing 0.5 mg · L-1 IAA and 1.0 mg · L-1 GA3 till adventitious shoot produced.%@@ 红枣营养丰富、富含维生素,深受广大消费者喜爱,但由于枣(Zizyphus jujuba Mill.)树在生长过程中经常受到细菌、真菌等病害的危害,制约了红枣的产量.通过品种改良可以获得优良的枣树品种,但由于枣胚败育率高及落花落果严重等因素,导致利用常规杂交育种方法很难达到品种改良的目的.基因工程的外源基

  3. Recovering vitrified carnation (Dianthus caryophyllus L.) shoots using Bacto-Peptone and its subfractions.

    Sato, S; Hagimori, M; Iwai, S


    Vitrified shoots regenerated from carnation petals (Dianthus caryophyllus L. cv. Scania) were recovered by culturing them in a medium containing 3.0 g/l Bacto-Peptone. Wax structures not found on vitrified shoots developed on the abaxial surface of leaves of recovered shoots and on those of normal leaves. Recovered shoots were rooted and successfully acclimatized while vitrified shoots could not survive the acclimatization process. The Bacto-Peptone solution was fractionated and the efficiency of each fraction for the recovery of vitrification was examined. Only basic, non high molecular fractions whose molecular weight was less than 10,000 were effective.

  4. 陆地棉农杆菌介导茎尖的遗传转化的直接器官再生%Agrobacterium-mediated Transformation and Regeneration by Direct Shoot Organogenesis in Cotton (G. hirsutum



    @@ Genotype independent transformation and regeneration of Indian cotton ( Gossypium hirsutum L. ) cultivar was standardized with BtCry 1A (b ) gene by Agrobacterium-mediation.Apical meristem of elite G. hirsutum cultivar LRK-516 and LRA 5166 were co-cultivated with A. tumefaciens LBA 4404 carrying synthetic BtCry 1A (b) +npt-II genes.

  5. Ectopic expression of Malus domestica class 1 knox genes altered growth and development of Nicotiana tabacum and Prunus domestica, and induced adventitious shoot regeneration from leaf explants without exogenous cytokinin

    Transgenic tobacco (Nicotiana tabacum L) and plum (Prunus domestica L) plants were regenerated by transforming with apple class 1 KNOX genes (MdKNP1 and MdKNP2) or a corn KN1 (ZmKN1) gene. Transgenic tobacco plants were produced in vitro from transformed leaf discs in the absence of cytokinin in th...

  6. 刺梨茎尖的玻璃化超低温保存及植株再生%Cryopreservation of in vitro Rosa roxburghii shoot-tips by vitrification and its regeneration

    陈红; 程秀枝; 林田


    【目的】建立刺梨茎尖超低温保存技术体系,为刺梨种质资源的长期稳定保存提供新途径。【方法】以刺梨为材料,研究了适合茎尖超低温保存的蔗糖预培养时间与浓度、预处理时间、玻璃化液处理时间等影响因素。【结果】适合超低温保存芽诱导的适宜培养基为MS+0.5 mg·L-16-BA+30 g·L-1蔗糖+7 g·L-1琼脂。刺梨茎尖玻璃化法超低温保存体系为:约0.5 cm长的腋芽茎尖在4℃条件下于培养基MS+0.5 mg·L-16-BA+0.05 mg·L-1IAA+0.3 mo1·L-1蔗糖+7 g·L-1琼脂上预培养3 d,切取约2 mm长的茎尖,室温下LS装载液处理40~50 min,然后用玻璃化液PVS2于0℃下处理40 min,换入新鲜的PVS2,迅速投入液氮中。保存24 h后,在40℃水浴中化冻,用MS+1.2 mol·L-1蔗糖+100 mg·L-1Vc+0.5 mg·L-1GA3培养基洗涤2次,接种到MS+0.3 mol·L-1蔗糖的培养基上暗培养1 d,再转接到MS+0.1mg·L-16-BA+0.05 mg·L-1IAA+30 g·L-1蔗糖+7.0 g·L-1琼脂上暗培养7 d后转入正常光下培养,成活率可达44.3%。【结论】建立了刺梨茎尖超低温保存技术体系。%【Objective】This research aims at developing a cryopreservation system of in vitro Rosa roxburghii Tratt shoot-tips,and thereby establishing a foundation for long-term and stable preservation of Rosa roxburghii Tratt germplasm resources.【Method】Taking Rosa roxburghii Tratt as materials,factors for cryopreservation of in vitro Rosa roxburghii Tratt shoot-tips such as sucrose preculture,LS pretreatment time,and PVS2 treatment time were investigated.【Result】 The suitable medium for bud break and growth was MS + 0.5 mg·L-1 6-BA + 30 g·L-1 sucrose + 7 g·L-1 agar.A system of cryopreservation for in vitro Rosa roxburghii Tratt shoot-tips was established: the axillary shoot tips which were about 0.5 cm in length were precultured on MS medium containing 0.5 mg·L-1 6-BA,0.05 mg·L-1 IAA,0.3 mol·L-1 sucrose and 7.0 g·L-1 agar for 3

  7. Violence and school shootings.

    Flannery, Daniel J; Modzeleski, William; Kretschmar, Jeff M


    Multiple-homicide school shootings are rare events, but when they happen they significantly impact individuals, the school and the community. We focus on multiple-homicide incidents and identified mental health issues of shooters. To date, studies of school shootings have concluded that no reliable profile of a shooter exists, so risk should be assessed using comprehensive threat assessment protocols. Existing studies primarily utilize retrospective case histories or media accounts. The field requires more empirical and systematic research on all types of school shootings including single victim incidents, those that result in injury but not death and those that are successfully averted. We discuss current policies and practices related to school shootings and the role of mental health professionals in assessing risk and supporting surviving victims.

  8. Adventitious Shoots Regeneration from Leaves of Soft-seeded Pomegranate ( Punica granatum软籽石榴(Punica granatum叶片再生体系的研究

    张全军; 秦改花; 黄文江; 许天龙


    为建立软籽石榴的离体高效再生体系,试验以新梢为材料建立了软籽石榴的无菌体系,并试验了不同激素组合对软籽石榴增殖效果的影响;以叶片为外植体研究了不同培养基组合对不定芽再生频率和伸长的影响.结果表明,茎段增殖培养的最适培养基为MS +6-BA 0.3 mg/L+ KT0.3 ~0.4 mg/L+ NAA 0.1 mg/L;叶片不定芽诱导的最适培养基为MS +TDZ 0.6mg/L+NAA 0.2 mg/L,在不定芽诱导培养基中添加0.6 mg/L的GA3对不定芽的伸长效果较好.在1/2MS+ NAA 0.2 mg/L+ BA 0.2 mg/L+ AC 0.5g/L培养基增殖培养所得芽苗生根效果最优.%To establish the system of rapid in vitro propagation of pomegranate, stems were used to study the effects of different hormone combination on the multiplication of shoots; the leaves were used to study the effects of different hormone combination on the adventitious shoots inducement, then rooting of shoots were studied. The results showed that the optimum media for multiplication of shoots were MS +6-BA0. 3 mg/L+ KT0.3-0.4 mg/L + NAA 0. 1mg/L, the optimum media for adventitious buds inducement were MS + TDZ 0.6 mg/L + NAA 0. 2 mg/L, the adventitious buds grew well on the inducement medium added GA0.6 mg/L, the optimum media for rooting were 1/2MS + NAA 0.2 mg/L+ IBA 0.2 mg/L + AC 0.5 g/L.

  9. Cytological studies on adventitious shoots and minitubers of a monoploid potato clone

    Hermelink, J; Jacobsen, Evert; Pijnacker, Laas; Witholt, Bernard; de Vries, J.N.; Feenstra, W.J.


    A three step procedure for adventitious shoot regeneration on leaf explants of monoploid potato clone H7322 and a minituber induction procedure on stem segments have been described. Chromosome counts on 92 adventitious shoots showed that 85% of them had been polyploidized, i.e., 71% were diploid, 1%

  10. Proliferative multifocal leukoplakia better name that proliferative verrucous leukoplakia

    Aguirre-Urizar Jose M


    Abstract In this letter I propose the name "Proliferative Multifocal Leukoplakia" with the goal of reducing under-diagnosis of this disease, improve the early diagnosis, try to make an early therapy and control, and prevent its malignant transformation.


    Ely ZAYOVA


    Full Text Available A protocol for indirect shoot organogenesis of Solanum melongena ‘Larga Negra’ and ‘Black Beauty’ was established using hypocotyl and cotyledon derived calluses. The maximum morphogenic callus induction was observed from cultured cotyledons of 30-days old seedlings on Murashige and Skoog (MS medium containing 2.0 mg/l α-naphthalene acetic acid and 0.5 mg/l 6-benzylaminopurine. The highest percentage of shoot regeneration and the highest mean number of shoots/callus were obtained on hormone-free MS medium. In terms of callus induction and subsequent plant regeneration, cotyledon explants were more responsive than hypocotyl explants. Regenerated shoots (2-3 cm were rooted on MS hormone-free medium or medium containing 0.1 mg/l indole-3-butyric acid. About 90% of regenerated plantlets survived under field conditions after hardening in the glasshouse. Several somaclones exhibiting useful variation would to be proposed as initial plant material for eggplant breeding programs.

  12. Study on Rooting Culture and Rooting Anatomy of Tree Peony 'Wulong Pengsheng' Regenerated Shoots%牡丹‘乌龙捧盛’组培苗生根及生根解剖学研究

    贾文庆; 徐小博; 刘会超; 李纪元


    The tissue-cultured seedlings of tree peony ‘ Wulong Pengsheng' were used to study the effects of different plant growth regulators,culture methods,and holdfast on rooting.The morphological structure change during rooting was also observed using the method of paraffin section.The result showed that the best combination of plant growth regulators for rooting was IBA 3.0 mg · L-1 + NAA 0.6 mg · L-1.The treatment under the temperature of 4℃ for ten days was benefit to rooting,and the rate could reach 75.67%.It was identified that the adventitious root primordia of shoot in vitro originated from the vascular cambium cells,especially,the cross areas of cambium and pith ray and they started to differentiate at the 5th day and lasted to the 12th day.If the shoots were cultured in the root inducing medium for 12 days,it would lead to not only descend of rooting rate,but also showing callus of stem base,and leaf senescent.However,if they were transferred into the medium without hormone in time,the root primordial protruded the epidermis and developed normally after 5 days' culture.

  13. Influences of antibiotics on plantlet regeneration via organogenesis in loblolly pine (Pinus taeda L.)

    TANG Wei; Latoya Harris; Ronald J. Newton


    Three antibiotics ampicillin, carbenicillin, and cefotaxime were evaluated for their effects on induction, growth, and differentiation of organogenic calli, as well as rooting of regenerated shoots of three loblolly pine (Pinus taeda L.) genotypes. Of the antibiotics administered, cefotaxime maximally increased the frequency of callus formation and growth rate of organogenic calli, carbenicillin maximally increased the frequency of shoot regeneration and the average number of adventitious shoots per piece of organogenic callus, ampicillin maximally decreased the rooting frequency of regenerated shoots and mean number of roots per regenerated shoot, in comparison with antibiotic-free media. Compared with the control, ampicillin minimally increased the frequency of callus formation, cefotaxime minimally increased the frequency of shoot regeneration, and carbenicillin minimally decreased the rooting frequency of regenerated shoots in three loblolly pine genotypes tested. All three antibiotics increased the frequencies of callus formation and shoot regeneration, and reduced the rooting frequency of regenerated shoots suggested that the establishment of an efficient Agrobacterium tumefaciens-mediated transformation protocol for stable integration of foreign genes into loblolly pine need to select a suitable antibiotic. This investigation could be useful for optimizing genetic transformation of conifers.

  14. Improved recovery of cryotherapy-treated shoot tips following thermotherapy of in vitro-grown stock shoots of raspberry (Rubus idaeus L.).

    Wang, Qiaochun; Valkonen, Jari P T


    Raspberry bushy dwarf virus (RBDV) can be efficiently eradicated from raspberry plants (Rubus idaeus) by a procedure combining thermotherapy and cryotherapy. However, the bottleneck of this procedure is that, following thermotherapy, cryopreserved shoot tips become chlorotic during regrowth and eventually die after several subcultures. In addition, survival of heat-treated stock shoots and recovery of cryopreserved shoot tips following thermotherapy are low. The present study focused towards improving regrowth of cryopreserved raspberry shoot tips following thermotherapy. Results showed that preconditioning stock shoots with salicylic acid (SA; 0.01-0.1 mM) markedly increased survival of stock shoots after 4 weeks of thermotherapy. Regrowth of cryopreserved shoot tips following thermotherapy was also significantly enhanced when SA (0.05-0.1 mM) was used for preconditioning stock shoots. Addition of either Fe-ethylenediaminetetracetic acid (Fe-EDTA, 50 mg per L) or Fe-ethylenediaminedi(o)hydroxyphenylacetic acid (Fe-EDDHA, 50 mg per L) to post-culture medium strongly promoted regrowth and totally prevented chlorosis of shoots regenerated from cryopreserved shoot tips following thermotherapy. Using the parameters optimized in the present study, about 80 percent survival of heat-treated stock shoots and about 33 percent regrowth of cryopreserved shoot tips following thermotherapy were obtained. Morphology of plants regenerated from cryopreserved shoot tips following thermotherapy was identical to that of control plants, based on observations of leaf shape and size, internode length and plant height. Optimization of the thermotherapy procedure followed by cryotherapy will facilitate the wider application of this technique to eliminate viruses which can invade meristems.

  15. Matriptase zymogen supports epithelial development, homeostasis and regeneration

    Friis, Stine; Tadeo, Daniel; Le-Gall, Sylvain M.


    Background Matriptase is a membrane serine protease essential for epithelial development, homeostasis, and regeneration, as well as a central orchestrator of pathogenic pericellular signaling in the context of inflammatory and proliferative diseases. Matriptase is an unusual protease in that its...

  16. Spine micromorphology of normal and hyperhydric Mammillaria gracilis Pfeiff. (Cactaceae) shoots.

    Peharec, P; Posilović, H; Balen, B; Krsnik-Rasol, M


    Artificial conditions of tissue culture affect growth and physiology of crassulacean acid metabolism plants which often results in formation of hyperhydric shoots. In in vitro conditions Mammillaria gracilis Pfeiff. (Cactaceae) growth switches from organized to unorganized way, producing a habituated organogenic callus which simultaneously regenerates morphologically normal as well as altered hyperhydric shoots. In this study, influence of tissue culture conditions on morphology of cactus spines of normal and hyperhydric shoots was investigated. Spines of pot-grown Mammillaria plants and of in vitro regenerated shoots were examined with stereo microscope and scanning electron microscope. The pot-grown plants had 16-17 spines per areole. In vitro grown normal shoots, even though they kept typical shoot morphology, had lower number of spines (11-12) and altered spine morphology. This difference was even more pronounced in spine number (six to seven) and morphology of the hyperhydric shoots. Scanning electron microscopy analysis revealed remarkable differences in micromorphology of spine surface between pot-grown and in vitro grown shoots. Spines of in vitro grown normal shoots showed numerous long trichomes, which were more elongated on spines of the hyperhydric shoots; the corresponding structures on spine surface of pot-grown plants were noticed only as small protrusions. Scanning electron microscopy morphometric studies showed that the spines of pot-grown plants were significantly longer compared to the spines of shoots grown in tissue culture. Moreover, transverse section shape varies from elliptical in pot-grown plants to circular in normal and hyperhydric shoots grown in vitro. Cluster and correspondence analyses performed on the scanning electron microscope obtained results suggest great variability among spines of pot-grown plants. Spines of in vitro grown normal and hyperhydric shoots showed low level of morphological variation among themselves despite the


    徐进; 王玉珍; 罗景兰


    The plantlets in vitro of Jojoba were treated by 1~3.5 mg/L of Lanthanum nitrate on subculture medi um( MS containing 2 mg/L 6-BA and 0.5 mg/L GA3), the result showed a significant promotion on shoot growth and proliferation. 2.5 mg/L had a very significant effect on shoot differentiation. Roots formation could be improved by using 1~2 mg/L of Lanthanum nitrate on the rooting medium(MS1/2 supplemented with 3 mg/L NAA and 1.5 mg/L IBA), and 2 mg/L had a very significant effect. High concentration of Lanthanum nitrate inhibited the plantlets growth. The result indicated that different plant organs had different sensitivity on the concentration of Lanthanum nitrate. 2 cm high test-tube shoots were treated by 25 mg/L IBA or NAA for 30 min, then cultivated into sand substrate. Plantlets were elaborately reared under 20~ 30 ℃ in a greenhouse. Uncovered the plastic membrane after 50 d. Keep the light intensity at 3000 lx and relative hurnidity 85 % . The survival percent of the plantlets come up to 75 %.%在增殖培养基(改良MS+2 mg/L6-BA+0.5 mg/TGA3)中添加1~3.5 mg/L硝酸镧,对霍霍巴试管苗生长有显著促进作用,2.5 mg/L硝酸镧对多芽分化有极显著的促进;在生根培养基(改良1/2MS+3 mg/L IBA+1.5 mg/L NAA)中,1~2 mg/L的La(NO3)3对根的分化有显著的促进作用,生根率提高,最佳浓度为2.0 mg/L.过高的浓度对试管苗生长有一定抑制.试验表明,不同器官对硝酸镧的敏感程度不同.取2cm高以上的霍霍巴试管苗,用25 mg/L IBA或NAA处理30 min,扦插于沙基质中.保持室温20~30℃.50d后揭去覆膜,保持光强3000 lx,相对湿度85%以上.正常管理条件下成活率达75%.

  18. School Shootings Stun Reservation

    Borja, Rhea R.; Cavanagh, Sean


    This article deals with the impact brought by the school shootings at Red Lake Indian Reservation in Minnesota to the school community. A deeply troubled 16-year-old student shot and killed seven other people and himself at a high school. The nation's deadliest school attack since the 1999 slayings at Colorado's suburban Columbine High School took…

  19. Distributed trouble-shooting

    Post, W.M.; Bogaard, S.A.A. van den; Rasker, P.C.


    When knowledge, required for trouble-shooting at sea, can be supplied real-time but from a distance, problems, such as with the limited availability of specialists, and the high costs of maintenance, may be tackled. Unclear is, however, how this redistribution of knowledge will work in practice. We

  20. The Binomial Distribution in Shooting

    Chalikias, Miltiadis S.


    The binomial distribution is used to predict the winner of the 49th International Shooting Sport Federation World Championship in double trap shooting held in 2006 in Zagreb, Croatia. The outcome of the competition was definitely unexpected.

  1. Improved method of in vitro regeneration in Leucaena leucocephala - a leguminous pulpwood tree species.

    Shaik, Noor M; Arha, Manish; Nookaraju, A; Gupta, Sushim K; Srivastava, Sameer; Yadav, Arun K; Kulkarni, Pallavi S; Abhilash, O U; Vishwakarma, Rishi K; Singh, Somesh; Tatkare, Rajeshri; Chinnathambi, Kannan; Rawal, Shuban K; Khan, Bashir M


    Leucaena leucocephala is a fast growing multipurpose legume tree used for forage, leaf manure, paper and pulp. Lignin in Leucaena pulp adversely influences the quality of paper produced. Developing transgenic Leucaena with altered lignin by genetic engineering demands an optimized regeneration system. The present study deals with optimization of regeneration system for L. leucocephala cv. K636. Multiple shoot induction from the cotyledonary nodes of L. leucocephala was studied in response to cytokinins, thidiazuron (TDZ) and N(6)-benzyladenine (BA) supplemented in half strength MS (½-MS) medium and also their effect on in vitro rooting of the regenerated shoots. Multiple shoots were induced from cotyledonary nodes at varied frequencies depending on the type and concentration of cytokinin used in the medium. TDZ was found to induce more number of shoots per explant than BA, with a maximum of 7 shoots at an optimum concentration of 0.23 µM. Further increase in TDZ concentration resulted in reduced shoot length and fasciation of the shoots. Liquid pulse treatment of the explants with TDZ did not improve the shoot production further but improved the subsequent rooting of the shoots that regenerated. Regenerated shoots successfully rooted on ½-MS medium supplemented with 0.54 µM α-naphthaleneacetic acid (NAA). Rooted shoots of Leucaena were transferred to coco-peat and hardened plantlets showed ≥ 90 % establishment in the green house.

  2. Optimization of callus induction and regeneration system for ...



    Oct 19, 2009 ... system for Pakistani wheat cultivars Kohsar and. Khyber-87. Sabahat .... whitish to creamy in color and larger calli than those obtained at other .... growth regulators on direct shoot regeneration of wheat (Triticum aestivum L.).

  3. Melatonin promotes adventitious root regeneration in in vitro shoot tip explants of the commercial sweet cherry rootstocks CAB-6P (Prunus cerasus L.), Gisela 6 (P. cerasus × P. canescens), and MxM 60 (P. avium × P. mahaleb).

    Sarropoulou, Virginia N; Therios, Ioannis N; Dimassi-Theriou, Kortessa N


    The objectives of this study were to test the effects of melatonin (N-acetyl-5-methoxytryptamine), a natural compound of edible plants on the rooting of certain commercial sweet cherry rootstocks. Shoot tip explants from previous in vitro cultures of the cherry rootstocks CAB-6P (Prunus cerasus L.), Gisela 6 (P. cerasus × P. canescens), and M × M 60 (P. avium × P. mahaleb) were included in the experiment. The effect of indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) alone or in combination with melatonin was tested concerning their rooting potential. Seven concentrations of melatonin (0, 0.05, 0.1, 0.5, 1, 5, and 10 μM) alone or in combination with 5.71 μM of IAA or 4.92 μM of IBA were tested. For each rootstock, 21 treatments were included. The explants were grown in glass tubes containing 10 mL of substrate. The parameters measured include rooting percentage, number of roots per rooted explant, root length, and callus formation. The data presented in this study show that melatonin has a rooting promoting effect at a low concentration but a growth inhibitory effect at high concentrations. In the absence of auxin, 1 μM melatonin had auxinic response concerning the number and length of roots, but 10 μM melatonin was inhibitory to rooting in all the tested rootstocks. The final conclusion of this experiment is that exogenously applied melatonin acted as a rooting promoter and its action was similar to that of IAA.

  4. Effects of Antibiotics on Callus Growth and Shoot Regeneration of Sisal%抗生素对剑麻愈伤组织生长和植株再生的影响

    张燕梅; 李俊峰; 周文钊; 林映雪


    The dose response assay was performed to insight into the effects of kanamycin, hygromycin, cefotaxime, and carbenicillin on the callus growth, adventitious buds regeneration and root induction of sisal. The optimum concentrations of cefotaxime and carbenicillin inhibiting Agrobacterium was determined. The results showed that the callus growth and adventitious buds regeneration were greatly inhibited by hygromycin, followed by kanamycin, cefotaxime and carbenicillin. Root induction was inhibited by each of the four antibiotics, with the order of cefotaxime > kanamycin > carbenicillin > hygromycin. The growth of Agrobacterium was completely inhibited by 200 mg/L cefotaxime or carbenicillin. In conclusion, 100 mg/L kanamycin, 50 mg/L hygromycin, 200 mg/L cefotaxime or carbenicillin was recommended to screen transformed tissue in Agrobacterium-mediated transformation of sisal.%研究卡那霉素、潮霉素、头孢霉素和羧苄青霉素对剑麻愈伤组织生长、不定芽分化及生根的影响,并确定抑制农杆菌生长的头孢霉素、羧苄青霉素的质量浓度.结果表明:潮霉素明显抑制剑麻愈伤组织生长和不定芽分化,卡那霉素次之,头孢霉素和羧苄青霉素相对较小;4种抗生素均能抑制剑麻生根,其抑制效果依次为头孢霉素>卡那霉素>羧苄青霉素>潮霉素.头孢霉素和羧苄青霉素的浓度大于200 mg/L时,农杆菌生长完全被抑制.在筛选剑麻转化体时,卡那霉素和潮霉素的使用浓度分别以100、50 mg/L为宜,羧苄青霉素和头孢霉素的使用浓度均为200 mg/L.

  5. Shooting Star Experiment


    The Shooting Star Experiment (SSE) is designed to develop and demonstrate the technology required to focus the sun's energy and use the energy for inexpensive space Propulsion Research. Pictured is an engineering model (Pathfinder III) of the Shooting Star Experiment (SSE). This model was used to test and characterize the motion and deformation of the structure caused by thermal effects. In this photograph, alignment targets are being placed on the engineering model so that a theodolite (alignment telescope) could be used to accurately measure the deformation and deflections of the engineering model under extreme conditions, such as the coldness of deep space and the hotness of the sun as well as vacuum. This thermal vacuum test was performed at the X-Ray Calibration Facility because of the size of the test article and the capabilities of the facility to simulate in-orbit conditions

  6. Proliferative periostitis: a case report.

    Zand, Vahid; Lotfi, Mehrdad; Vosoughhosseini, Sepideh


    Proliferative periostitis of Garré represents a periosteal reaction to the presence of infection or other irritants. This can be odontogenic or nonodontogenic. This is a case report of an odontogenic periostitis resulting from endodontic origin. It was successfully treated by nonsurgical root canal therapy without using antibiotic therapy during the treatment of this case.

  7. In vitro regeneration of Passiflora miniata Mast

    Paula Pinheiro Carvalho


    Full Text Available Passiflora miniata is a wild species native to the Southern Amazon, with ornamental potential due to the beauty of its flowers of intense red coloration. Reports in the literature about the species are still insipid. The aim of the present study was to induce the regeneration of P. miniata by the de novo organogenesis from mature zygotic embryos. The zygotic embryos were isolated and cultivated into the MS medium with the addition of 6-Benzyladenine (BA, Thidiazuron (TDZ and Kinetin (KIN growth regulators. The de novo regeneration from the zygotic embryos occurred directly and indirectly. A percentage of 80% of the explants cultivated in the presence of BA had direct organogenesis and 20% by the indirect way, with TDZ 60% were regenerated by the direct and 40% by the indirect way. Regarding the treatments with KIN, 58% of the explants had regeneration by direct and 42% by the indirect organogenesis. The development of shoot primordia initiated with the formation of organogenic structures that later differentiated into multi-shoots. The highest mean number of shoots (40.0 shoots per explants was obtained on 0.75 mg L-1BA. Conversely, using 0.50 mg L-1 TDZ or KIN, the highest number of shoots were 7.2 and 3.6, respectively.

  8. The florigen genes FT and TSF modulate lateral shoot outgrowth in Arabidopsis thaliana.

    Hiraoka, Kazuhisa; Yamaguchi, Ayako; Abe, Mitsutomo; Araki, Takashi


    Successful sexual reproduction of a plant with prolific seed production requires appropriate timing of flowering and concomitant change of architecture (e.g. internode elongation and branching) to facilitate production of the optimal number of flowers while enabling continued resource production through photosynthesis. Florigen is the prime candidate for a signal linking the two processes. Growth analysis of lateral shoots in mutants of FLOWERING LOCUS T (FT) and TWIN SISTER OF FT (TSF) revealed a delay in the onset of outgrowth and a reduction of the growth rate in ft plants in long-day (LD) conditions and in tsf plants in short-day (SD) conditions. Thus, as in the case of floral transition, FT and TSF play dominant roles in LD and SD conditions, respectively, in the promotion of lateral shoot development. Differential expression patterns of the two genes were in good agreement with their differential roles both in the floral transition and in lateral shoot development under contrasting photoperiod conditions. By manipulating florigen production after bolting of the primary shoot, it was shown that florigen promotes lateral shoot growth independently of its effect on the floral transition of the primary shoot. Analysis of growth and gene expression in lateral shoots of the mutants suggests that the loss of florigen leads to a reduced rate of flower formation on lateral shoots. Together, we propose that the two florigen genes are an important key to linking the floral transition and lateral shoot development to maximize the reproductive success of a plant.

  9. Cell Ultrastructure of Kiwifruit (Actinidia chinensis) Shoot Tips During Cryopreservation

    XU Xiao-biao; CAI Zi-guo; GU Qing-qing; ZHANG Qiu-ming


    The changes in the cell ultrastructure of in vitro cultured shoot tips from dwarf genotype of kiwifruit (Actinidia chinensis Ganmi 5) during cryopreservation were investigated. Shoot tips were preserved in liquid nitrogen using vitrification, and the cell ultrastructure was examined using transmission electron microscopy (TEM). The regular ultrastructure of the cell wall, cell membrane and nucleus of shoot tips could be damaged during the freezing and thawing associated with preservation using liquid nitrogen. The cell plasmolysis was increased and freezing tolerance was improved after preculturing and dehydrating in a preservation and vitrification solution (PVS2 ) (30% glycerol (Gly)+ 15% ethylene glycol (EG)+ 15% dimethylsulfoxide (DMSO) + 0.4 mol L-1 sucrose). The structure of some cells with low degree of injury and reversible damage was similar to that of the control and they could undergo normal cell division and differentiation. Besides, they could recover automatically and regenerate after their reculture.

  10. The endodermis and shoot gravitropism

    Tasaka, M; Kato, T; Fukaki, H


    Shoots and roots of higher plants exhibit negative and positive gravitropism, respectively. A variety of gravitropic mutants have recently been isolated from Arabidopsis, the characterization of which demonstrates that the molecular mechanisms of the gravitropic responses in roots, hypocotyls and inflorescence stems are different. The cytological and molecular analysis of two mutants, shoot gravitropism 1 (sgrl), which is allelic to scarecrow (scr), and sgr7, which is allelic to short-root(shr), indicate that the endodermis is the site of gravity perception in shoots. These data suggest a new model for shoot gravitropism.

  11. PLETHORA genes control regeneration by a two-step mechanism

    Kareem, Abdul; Durgaprasad, Kavya; Sugimoto, Kaoru; Du, Yujuan; Pulianmackal, Ajai J.; Trivedi, Zankhana B.; Abhayadev, Pazhoor V.; Pinon, Violaine; Meyerowitz, Elliot M.; Scheres, Ben; Prasad, Kalika


    Summary Regeneration, a remarkable example of developmental plasticity displayed by both plants and animals, involves successive developmental events driven in response to environmental cues. Despite decades of study on the ability of the plant tissues to regenerate a complete fertile shoot syste

  12. Micro-propagation of Lepedium meyenii Walp. (Maca) by shoot culture

    ChengHua; YuLongjiang; HuQiongyue; SunYouping; JinWenwen; ChenShancai; LiMaoteng


    The callus induction and plant regeneration system for an important plant, Lepedium meyenii Walp., has been established. Calli were induced from cotyledons petioles of Lepedium meyenii Walp within 4 weeks in a modified MS medium supplemented with BA plus NAA. The highest percentage of callus formation (57. 1% ) was found on MS medium supplemented with 0. 5 mg l-1 BA and 0. 5 mg l-1 NAA. During subculture on the shoot formation medium, most of calli proliferated and 50% -60% formed shoots. About 66.7% of shoots formed into roots on 1/2 strength MS containing 0.5mg l-1 IBA after 4 weeks in culture. Chromosome count confirmed the number of the regeneration Maca plantlet was the same as that of the native plant(8x=64) .For regeneration of plantlets, from seedling via primary callus production, a four-step process of organogenes is required about 16 weeks.

  13. Alginate-encapsulation of shoot tips of jojoba [Simmondsia chinensis (Link) Schneider] for germplasm exchange and distribution.

    Kumar, Sunil; Rai, Manoj K; Singh, Narender; Mangal, Manisha


    Shoot tips excised from in vitro proliferated shoots derived from nodal explants of jojoba [Simmondsia chinensis (Link) Schneider] were encapsulated in calcium alginate beads for germplasm exchange and distribution. A gelling matrix of 3 % sodium alginate and 100 mM calcium chloride was found most suitable for formation of ideal calcium alginate beads. Best response for shoot sprouting from encapsulated shoot tips was recorded on 0.8 % agar-solidified full-strength MS medium. Rooting was induced upon transfer of sprouted shoots to 0.8 % agar-solidified MS medium containing 1 mg l(-1) IBA. About 70 % of encapsulated shoot tips were rooted and converted into plantlets. Plants regenerated from encapsulated shoot tips were acclimatized successfully. The present encapsulation approach could also be applied as an alternative method of propagation of desirable elite genotype of jojoba.

  14. Influence of Plant Growth Regulators on In Vitro Shoot Multiplication and Plantlet Formation in Cassia angustifolia Vahl

    Iram Siddique


    Full Text Available ABSTRACTAn effective and improved plant regeneration system was successfully developed using shoot tip explants taken from a two years old mature plant of Cassia angustifolia. The effect of different cytokinins, [6-benzyladenine (BA, Kinetin (Kin and thidiazuron (TDZ] at different concentrations (0.5-10 µM were evaluated as augmented with Murashige and Skoog (MS 1962 medium. Among all the cytokinins tested, TDZ (5.0 µM was optimum in inducing multiple shoots as compared to BA and Kin. The rate of shoot multiplication was increased when optimal concentration (5.0 µM of BA and Kin was tested with different concentration (0.1-1.0 µM of Indole-3- acetic acid (IAA. Among all the combinations tested, the maximum rate of shoot multiplication was obtained on MS medium supplemented with 5.0 µM BA and 0.5 µM IAA. The number of the shoots and shoot length developed in TDZ was increased when transferred to MS medium devoid of TDZ. After every subculture, rate of the shoot multiplication and shoot length showed increment and continued even after fifth subculture without any decline rate. In vitro rooting in regenerated shoots were best obtained in half-strength MS medium supplemented with 2.0 µM indole-3- butyric acid (IBA. Plantlets with well-developed shoot and roots were successfully hardened off in earthen pots containing garden soil and grown in greenhouse with 80% survival rate.

  15. Enhanced regeneration in explants of tomato (Lycopersicon ...



    Jun 14, 2010 ... improvement of stress tolerance of crops are primary targets for plant molecular and genetic breeding (Yuasa et al., 2007) ... Abbreviations: CW, Coconut water; IAA, indole acetic acid; .... Rooting of shoots and transfer of plantlets to soil ..... vitro regeneration system in Sorghum [Sorghum bicolor (L.) Moench].


    Loeb, J


    It is well known that a long defoliated piece of stem of Bryophyllum calycinum forms shoots only at the apical or the two apical nodes, while when such a stem is cut into as many pieces as there are nodes each node produces shoots. It is shown in this paper that the dry weight of shoots produced in the apical nodes of a long piece of stem is approximately equal to the dry weight of shoots the same stem would have produced if it had been cut into as many pieces as it possesses nodes. Hence all the material which can be used for the growth of shoots goes into the most apical part of the stem and this accounts for the polar character of regeneration in this case. It seems that the mass of basal roots produced by a piece of defoliated stem also increases with the mass of the stem.

  17. Proliferative verrucous leukoplakia: An update.

    Munde, Anita; Karle, Ravindra


    Proliferative verrucous leukoplakia (PVL) is a rare form of oral leukoplakia, which was first described in 1985 by Hansen et al. Since then, various published case series have presented PVL as a disease with aggressive biological behavior due to its high probability of recurrence and a high rate of malignant transformation, usually higher than 70%. PVL is a long-term progressive condition, which is observed more frequently in elderly women, over 60 years at the time of diagnosis. The buccal mucosa and tongue are the most frequently involved sites. It develops initially as a white plaque of hyperkeratosis that eventually becomes a multifocal disease with confluent, exophytic and proliferative features with a progressive deterioration of the lesions, making it more and more difficult to control. Tobacco use does not seem to have a significant influence on the appearance or progression of PVL and may occur both in smokers and nonsmokers. Prognosis is poor for this seemingly harmless-appearing white lesion of the oral mucosa. At present, the etiology of PVL remains unclear as well as its management and diagnosis, which is still retrospective, late and poorly defined, lacking consensus criteria. This short review discusses the clinical and histopathological features, diagnosis, traditional treatment and the current management of the disease.

  18. Regeneration of okra (Abelmoschus esculentus L.) via apical shoot ...



    Oct 25, 2012 ... 1Nirmal Seeds Pvt. Ltd. Pachora, Dist – Jalgaon, India- 424201. ... 3.5 million tons (70% of the total world production) of okra produced from over .... media containing Kinetin (0.25, 0.5, 1.0, 1.5, 2.0 and 2.5 mg/L). After three to ...

  19. Factors influencing in vitro shoot regeneration of Macadamia ...



    Nov 19, 2008 ... The resultant increase in input ... PHYTAGEL® (Sigma-Aldrich, Inc 3050 Spruce street, St Louis .... integrifolia cultivar KRG-15 explants on MS medium after six weeks in .... (BTA) and the Kenya Agricultural Productivity Project.

  20. In Vitro Regeneration of Endangered Medicinal Plant Heliotropium kotschyi (Ramram).

    Sadeq, Manal Ahmed; Pathak, Malabika Roy; Salih, Ahmed Ali; Abido, Mohammed; Abahussain, Asma


    Heliotropium kotschyi (Ramram) is an important endangered medicinal plant distributed in the Kingdom of Bahrain. Plant tissue culture technique is applied for ex situ conservation study. Nodal stem segments are cultured in modified MS media supplemented with various combination and concentration of plant growth regulators (PGRs). Plants are regenerated via shoot organogenesis from the nodal meristems. Plants are regenerated in three different steps: initial shoot development, shoot multiplication, and rooting. After 4 weeks of culture, 100 % explants respond to shoot initiation on the medium containing 8.88 μM BAP and 5.71 μM IAA. The highest frequency of shoot regeneration is observed in the same media after second subculture of shoots. The highest rooting frequency is observed in the presence of 2.85 μM IAA. After root development, the plantlets are transferred to pots filled with soil and 60 % of plants survived after 45 days. This plant regeneration protocol is of great value for rapid desert plant propagation program.

  1. Liver regeneration.

    Mao, Shennen A; Glorioso, Jaime M; Nyberg, Scott L


    The liver is unique in its ability to regenerate in response to injury. A number of evolutionary safeguards have allowed the liver to continue to perform its complex functions despite significant injury. Increased understanding of the regenerative process has significant benefit in the treatment of liver failure. Furthermore, understanding of liver regeneration may shed light on the development of cancer within the cirrhotic liver. This review provides an overview of the models of study currently used in liver regeneration, the molecular basis of liver regeneration, and the role of liver progenitor cells in regeneration of the liver. Specific focus is placed on clinical applications of current knowledge in liver regeneration, including small-for-size liver transplant. Furthermore, cutting-edge topics in liver regeneration, including in vivo animal models for xenogeneic human hepatocyte expansion and the use of decellularized liver matrices as a 3-dimensional scaffold for liver repopulation, are proposed. Unfortunately, despite 50 years of intense study, many gaps remain in the scientific understanding of liver regeneration.

  2. Psychological preparation in sport shooting

    Ledecká, Kateřina


    Title: Psychological preparation in sport shooting Objectives: The objective of this thesis is usage of psychological preparation by sport shooting representation team in Czech Republic. How they are informed about psychological preparation. What it means to them. Which types of regulation they use and how they behave before and after a competition. Methods: A Questionnaire was used as a method for data obtaining. The questionnaire was compiled for the purposes of this Thesis. The researched ...

  3. Micropropagation of an elite F1 watermelon (Citrullus lanatus hybrid from the shoot tip of field grown plants

    Mohammad Khalekuzzaman


    Full Text Available The aim of this work was to develop a protocol for rapid micropropagation of an elite F1 hybrid watermelon cultivar using shoot tip of field-grown plants. Maximum frequency (73% of shoot tip showed growth response in MS medium supplemented with 5 mg l-1 benzyl adenine (BA and 0.1 mg l-1 indole-3 acetic acid (IAA. Upon transfer to cytokinin-enriched medium, the cultures produced multiple shoots and 2.0 mg l-1 BA was optimum in this respect. Addition of gibberellic acid (GA3 in the multiplication medium resulted in better growth of shoots. Rooting rate was 100% when shoots were obtained from second subculture were cultured in medium with 1.0 mg l-1 indole-3 butyric acid (IBA. The shoots produced more roots with increasing number of subcultures. About 72% of the regenerated plantlets acclimatized successfully and survived in the soil condition.

  4. Influence of foliar phenology and shoot inclination on annual photosynthetic gain in individual beech saplings: A functional-structural modeling approach

    Umeki, K.; Kikuzawa, K.; Sterck, F.J.


    We developed a functional-structural plant model for Fagus crenata saplings and calculated annual photosynthetic gains to determine the influences of foliar phenology and shoot inclination on the carbon economy of saplings. The model regenerated the three-dimensional shoot structure and spatial and

  5. A Real Shooting Star


    [figure removed for brevity, see original site] Click on the image for movie of A Real Shooting Star This artist's animation illustrates a star flying through our galaxy at supersonic speeds, leaving a 13-light-year-long trail of glowing material in its wake. The star, named Mira (pronounced my-rah) after the latin word for 'wonderful,' sheds material that will be recycled into new stars, planets and possibly even life. NASA's Galaxy Evolution Explorer discovered the long trail of material behind Mira during its survey of the entire sky in ultraviolet light. The animation begins by showing a close-up of Mira -- a red-giant star near the end of its life. Red giants are red in color and extremely bloated; for example, if a red giant were to replace our sun, it would engulf everything out to the orbit of Mars. They constantly blow off gas and dust in the form of stellar winds, supplying the galaxy with molecules, such as oxygen and carbon, that will make their way into new solar systems. Our sun will mature into a red giant in about 5 billion years. As the animation pulls out, we can see the enormous trail of material deposited behind Mira as it hurls along between the stars. Like a boat traveling through water, a bow shock, or build up of gas, forms ahead of the star in the direction of its motion. Gas in the bow shock is heated and then mixes with the cool hydrogen gas in the wind that is blowing off Mira. This heated hydrogen gas then flows around behind the star, forming a turbulent wake. Why does the trailing hydrogen gas glow in ultraviolet light? When it is heated, it transitions into a higher-energy state, which then loses energy by emitting ultraviolet light - a process known as fluorescence. Finally, the artist's rendering gives way to the actual ultraviolet image taken by the Galaxy Evolution Explorer Mira is located 350 light-years from Earth in the constellation Cetus, otherwise known as the whale. Coincidentally, Mira and its 'whale of a tail' can be

  6. Vitrectomy for proliferative diabetic retinopathy

    Chao Peng


    Full Text Available AIM:To observe the clinical effect of vitrectomy for proliferative diabetic retinopathy(PDR.METHODS: The clinical data of 55 cases(65 eyes, underwent vitrectomy, membrane peeling, endolaser photocoagulation and silicone oil or C3F8 injection, were retrospectively studied. During 6 months to 1 year follow-up period, visual acuity, intraocular pressure, retinal conditions and complications were observed.RESULTS: All 65 eyes received vitrectomy, of which silicone oil was tamponaded in 32 eyes, C3F8 was injected in 8 eyes, BBS was filled in 25 eyes. Visual improvement achieved in 42 eyes. Two eyes were manually vision, form count fingers to 0.05 in 18 eyes, >0.05-0.1 in 28 eyes, >0.1-0.3 in 12 eyes and >0.3 in 5 eyes. Retinal hole was occurred in 7 eyes, limitations fibrosis membrane remained in 8 eyes, retinal detachment appeared in 5 eyes, IOP increased in 18 eyes, vitreous hemorrhage relapsed in 12 eyes, 36 eyes received supplemental photocoagulation treatment 1-3 times after operation.CONCLUSION:Vitrectomy combined endophotocoagulation is an effective treatment for PDR. Silicone oil tamponade can limit the hemorrhage.

  7. Two ways of plant regeneration from immature cotyledons of pea

    Anna Nadolska-Orczyk


    Full Text Available Two different systems of plant regeneration via organogenesis and embryogenesis from immature cotyledons of pea (Pisum sativum L. were developed. The first system was direct multiple shoot regeneration from the proximal to the embryo axis, injured part of cotyledon. The ability of six Polish cultivars to shoot formation was very high. The percent of regenerating cotyledons was from 73 to 86 and mean number of shoots from 3.5 to 9.9 after seven weeks of culture. This multiplification could be prolonged for next several months. The second system was somatic embryogenesis, initiating from the same part of cotyledon simultaneously with slowly proliferating callus. Only three out of six cultivars formed embryoids. The differences of ability to embryo formation ranged between 43% of responding explants for Heiga cultivar to only 6% for Cud Ameryki. The mean number of embryoids was from 4.2 to 2.3.

  8. Efficient culture protocol for plant regeneration from cotyledonary petiole explants of Jatropha curcas L.

    Ying Liu


    Full Text Available A high-frequency and reproducible protocol for induction of adventitious shoot buds and plant regeneration from cotyledonary petiole explants of Jatropha curcas L. has been developed. The cotyledonary petiole explants of J. curcas cultured directly on medium supplemented with thidiazuron (TDZ induce regeneration of poor quality shoot buds that have a low regeneration frequency. However, treating the explants with high concentrations (10–60 mg/L of TDZ solution for certain time periods (5–80 min significantly increased the regeneration frequency and improved the quality of the regenerated shoot buds. The best shoot buds induction (88.42% and number of shoot buds (12.67 per explant were observed when in vitro explants were treated with 20 mg/L TDZ solution for 20 min before being transferred on hormone-free medium after 30 days. Regeneration was also influenced by the orientation (horizontal or vertical of the explants on the medium, and by the origin of the cotyledonary petioles (in vitro or in vivo used for the preparation of explants. We performed subsequent experiments for elongation and rooting of the regenerated shoot buds. Addition of L-arginine to the medium was conducive to the elongation of the shoot buds. A concentration of 7.5 mg/L L-arginine yielded the best results. The elongated shoots could initiate roots to become intact plantlets in half-strength Murashige and Skoog medium containing 0.1 mg/L indole-3-butyric acid. After acclimatization, these plantlets could be transplanted to the soil and the growth was normal. Therefore, application of the methods described here helped to increase plant regeneration efficiency.

  9. Multiple pathways regulate shoot branching

    Catherine eRameau


    Full Text Available Shoot branching patterns result from the spatio-temporal regulation of axillary bud outgrowth. Numerous endogenous, developmental and environmental factors are integrated at the bud and plant levels to determine numbers of growing shoots. Multiple pathways that converge to common integrators are most probably involved. We propose several pathways involving not only the classical hormones auxin, cytokinins and strigolactones, but also other signals with a strong influence on shoot branching such as gibberellins, sugars or molecular actors of plant phase transition. We also deal with recent findings about the molecular mechanisms and the pathway involved in the response to shade as an example of an environmental signal controlling branching. We propose the TCP transcription factor TB1/BRC1 and the polar auxin transport stream in the stem as possible integrators of these pathways. We finally discuss how modeling can help to represent this highly dynamic system by articulating knowledges and hypothesis and calculating the phenotype properties they imply.

  10. Regeneration in Jatropha curcas: Factors affecting the efficiency of in vitro regeneration

    Sharma, Sweta K.


    Factors influencing in vitro regeneration through direct shoot bud induction from hypocotyl explants of Jatropha curcas were studied in the present investigation. Regeneration in J. curcas was found to be genotype dependent and out of four toxic and one non-toxic genotype studied, non-toxic was least responsive. The best results irrespective of genotype were obtained on the medium containing 0.5mgL-1 TDZ (Thidiazuron) and in vitro hypocotyl explants were observed to have higher regeneration efficiency as compared to ex vitro explant in both toxic and non-toxic genotypes. Adventitious shoot buds could be induced from the distal end of explants in all the genotypes. The number of shoot buds formed and not the number of explants responding to TDZ treatment were significantly affected by the position of the explant on the seedling axis. Explants from younger seedlings (≤15 days) were still juvenile and formed callus easily, whereas the regeneration response declined with increase in age of seedlings after 30 days. Transient reduction of Ca2+ concentrations to 0.22gL-1 in the germination medium increased the number of responding explants.Induced shoot buds, upon transfer to MS medium containing 2mgL-1 Kn (Kinetin) and 1mgL-1 BAP (6-benzylamino purine) elongated. These elongated shoots were further proliferated on MS medium supplemented with 1.5mgL-1 IAA (indole-3-acetic acid) and 0.5mgL-1 BAP and 3.01-3.91cm elongation was achieved after 6 weeks. No genotype specific variance in shoot elongation was observed among the toxic genotypes except the CSMCRI-JC2, which showed reduced response. And for proliferation among the toxic genotypes, CSMCRI-JC4 showed highest number of shoots formed. Among the rest, no significant differences were observed. The elongated shoot could be rooted by pulse treatment on half-strength MS medium supplemented with 2% sucrose, 3mgL-1 IBA (indole-3-butyric acid), 1mgL-1 IAA, 1mgL-1 NAA (α-naphthalene acetic acid) and subsequent transfer on 0

  11. [Proliferative diabetic retinopathy -- therapeutic approach (clinical case)].

    Burcea, M; Muşat, Ovidiu; Mahdi, Labib; Gheorghe, Andreea; Spulbar, F; Gobej, I


    We present the case of a 54 year old pacient diagnosed with neglected insulin dependent diabetes and proliferative diabetic retinopathy. Surgery was recommended and we practiced posterior vitrectomy, endolaser and heavy silicone oil endotamponade. Post-operative evolution was favorable.

  12. [Pathomorphology of membranes appearing in proliferative vitreoretinopathies].

    Laudańska-Olszewska, Iwona; Omulecki, Wojciech; Dziegielewski, Krzysztof; Pikulski, Zbigniew; Omulecka, Aleksandra


    Immunohistochemical techniques were used to investigate the cell content of epiretinal membranes occuring in proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR). Ten epiretinal membranes were obtained during surgery from eyes with PVR and five from eyes with PDR. This material was studied histopathologically and immunohistochemically. Retinal pigment epithelial cells, glial cells, macrophages, T lymphocytes and type IV collagen were identified in these membranes. The findings indicate that the cells mentioned possess a potential role in creating vitreoretinal membranes in PVR and PDR.

  13. A rapid and efficient in vitro regeneration system for lettuce (Lactuca sativa L.).

    Armas, Isabel; Pogrebnyak, Natalia; Raskin, Ilya


    Successful biotechnological improvement of crop plants requires a reliable and efficient in vitro regeneration system. Lettuce (Lactuca sativa L.), one the most important vegetable crops worldwide, is strongly genotype-dependent in terms of regeneration capacity, limiting the potential for biotechnological improvement of cultivars which show recalcitrance under currently available protocols. The effect of different nutrient sources, plant hormone combinations and activated charcoal supplementation on shoot induction efficiency was evaluated on the cultivar 'RSL NFR', which had previously shown poor regeneration efficiency. Multiple shoot organogenesis from cotyledon explants was recorded at the highest frequency and speed on Murashige and Skoog regeneration medium supplemented with 200 mg/l of activated charcoal, 3% sucrose, 10 mg/l benzylaminopurine and 0.5 mg/l naphthaleneacetic acid, which induced shoots through direct regeneration in 90.8 ± 7.9% of explants. High shoot induction efficiency was also observed, albeit not quantified, when using this medium on some other cultivars. This activated charcoal-containing regeneration medium might offer a rapid and efficient option for direct shoot induction in some lettuce genotypes that do not respond well to common lettuce regeneration protocols. This is also the first report of the effect of activated charcoal in lettuce tissue culture.

  14. Strigolactone inhibition of shoot branching

    Gomez-Roldan, M.V.; Fermas, S.; Brewer, P.B.; Puech-Pages, V.; Dun, E.A.; Pillot, J.P.; Letisse, F.; Matusova, R.; Danoun, S.; Portais, J.C.; Bouwmeester, H.J.; Becard, G.; Beveridge, C.A.; Rameau, C.; Rochange, S.F.


    A carotenoid-derived hormonal signal that inhibits shoot branching in plants has long escaped identification. Strigolactones are compounds thought to be derived from carotenoids and are known to trigger the germination of parasitic plant seeds and stimulate symbiotic fungi. Here we present evidence

  15. Strigolactone inhibition of shoot branching

    Gomez-Roldan, M.V.; Fermas, S.; Brewer, P.B.; Puech-Pages, V.; Dun, E.A.; Pillot, J.P.; Letisse, F.; Matusova, R.; Danoun, S.; Portais, J.C.; Bouwmeester, H.J.; Becard, G.; Beveridge, C.A.; Rameau, C.; Rochange, S.F.


    A carotenoid-derived hormonal signal that inhibits shoot branching in plants has long escaped identification. Strigolactones are compounds thought to be derived from carotenoids and are known to trigger the germination of parasitic plant seeds and stimulate symbiotic fungi. Here we present evidence

  16. Regeneration of Pelargonium in vitro

    Agnieszka Wojtania


    Full Text Available Pelargonium sp. has been a subject of numerous studies to deterimine the effec tiveness of in vitro techniques to produce a large number of pathogen-free plants. Regeneration of pelargonium plants from the different initial explants as well via organogenesis as via somatic embryogenesis has been obtained. The most effective adventitious shoot formation has been achieved from shoot tips and axillary buds using cytokinin or cytokinin/auxin combinations. Leaf explants, whose general have lower organogenic potency, regenerate better in the presence of thidiazuron. This growth regulator stimulate the somatic embryos production from hypocotyl and cotyledone explants too. The main problem in tissue culture propagation of Pelargonium has been the high tendency to formation of vigorously growing callus with low organogenic potency and rapid senescence of cultures. Moreover, the significant differen ces in requirements to the medium composition (minerals, organic compounds and growth regulators between Pelargonium cultivars has been observed. This makes difficult to develop an universaI method of Pelargonium micropropagation.

  17. My Regeneration:

    Carter, Dale


    and cultural referents shows that it offers an index to the album. Using its frontier setting and a variety of sacred and secular myths, symbols and icons, ‘Heroes and Villains,’ like Smile as a whole, offers historically-informed visions of national decline, crisis and regeneration that are at once critical...

  18. Training Visual Control in Wheelchair Basketball Shooting

    Oudejans, Raoul R. D.; Heubers, Sjoerd; Ruitenbeek, Jean-Rene J. A. C.; Janssen, Thomas W. J.


    We examined the effects of visual control training on expert wheelchair basketball shooting, a skill more difficult than in regular basketball, as players shoot from a seated position to the same rim height. The training consisted of shooting with a visual constraint that forced participants to use target information as late as possible.…

  19. Micropropagation of chokeberry by in vitro axillary shoot proliferation.

    Litwińczuk, Wojciech


    The black chokeberry-aronia (Aronia melanocarpa Elliot) is a shrub native to North America although nowadays well known in Eastern Europe. The fruits are regarded as the richest source of antioxidant phytonutrients among fruit crops and vegetables. Chokeberries can be easily propagated by seeds but this method is not recommended. Micropropagation is far more efficient than other conventional cloning methods like layering or softwood cuttings. Aronia clones are propagated in vitro through four- or three-stage method based on subculturing of shoot explants. The double diluted MS or full strength MS medium with elevated 50% Ca(2+) and Mg(2+) content are used in the initiation and proliferation chokeberry in vitro cultures, respectively. They are supplemented with 0.5-1.0 mg LBA, and 0.05 mg LIBA. The double-phase medium is recommended in the last passage before shoot rooting. The regenerated shoots could be rooted both in vitro on double diluted MS with 0.05 mg L(-1) IBA or in vivo in peat and perlite substrate and subsequently grown in the greenhouse.

  20. Effect of nodal positions, seasonal variations, shoot clump and ...



    May 7, 2014 ... from M/S Shidh Seeds Sales Corporation, Dehradun, India. After removal ... the responsive optimal media for observing their effect on shoot multiplication ..... shoots/ clump size in relation with shoot numbers and shoot length.

  1. Osteomyelitis with proliferative periostitis: an unusual case.

    Tong, Antonio C K; Ng, Irene O L; Yeung, K M Au


    Chronic osteomyelitis with subperiosteal new bone formation results from periosteal reaction to chronic inflammatory/infectious stimulation. In the maxillofacial region, it has traditionally been termed Garrè's osteomyelitis with proliferative periostitis and more recently periostitis ossificans. The term Garrè's osteomyelitis has been regarded as a misnomer by many authors in the recent literature. The term chronic osteomyelitis with proliferative periostitis, although cumbersome, is considered to be the most accurate description of the pathology. It usually affects the mandible of young patients secondary to dental infection. Management involves removal of the source of infection and antibiotic treatment. We present an unusual case of chronic osteomyelitis with proliferative periostitis affecting the mandible of a 12-year-old patient. The source of infection was related to the developing lower left third molar, which had apparently no communication with the oral cavity.

  2. Combined direct regeneration protocols in tissue culture of different cumin genotypes based on pre-existing meristems.

    Ebrahimie, Esmaeil; Hosseinzadeh, Abdolhadi; Nagavi, Mohammad Reza; Ghannadha, Mohammad Reza; Mohammadie-Dehcheshmeh, Manijeh


    Rapid and genotype-independent protocols for two direct in vitro morphogenesis pathways including direct shoot organogenesis from embryo and direct shoot proliferation from node have been developed in cumin (Cuminum cyminum L.). Direct regenerations occurring without passing callus phase are important since fewer somaclonal variation and genotype-dependency are likely to arise from these methods in comparison with regenerations trough callus. After embryo culture, shoots with single-cellular origin were regenerated from the meristematic zone of embryo without any intermediate callus phase. In contrast, proliferated shoots with multi-cellular origin were directly regenerated from the axillary buds (meristems) of node explants. Effects of different concentrations of 6-Benzylaminopurine (BAP), alpha-Naphthaleneacetic Acid (NAA) and Indole-3-kcetic Acid (IAA) on B5 medium of embryo and node cultures as well as subculture were studied in detail. In direct organogenesis pathway from embryo explant, 0.1 mg L(-1) NAA + 1 mg L(-1) IAA resulted the highest shoot regeneration response (89.5 shoots per regenerated explant), whereas 0.1 mg L(-1) BAP + 1 mg L(-1) NAA was the most effective combination in direct shoot proliferation from node explant (42 shoots per regenerated explant). BAP (cytokinin) revealed the inhibitory effect on induction of direct shoot organogenesis pathway from embryo explant, while low concentration of BAP (0.1 mg L(-1)) had positive effect on direct shoot proliferation pathway from node explant. Subculturing was not necessary for shoot multiplication and elongation in embryo culture, whereas multiplication and elongation of shoots in node culture were associated to subculture on growth regulator-free medium. In other part of study, the behavior of different cumin genotypes in direct regeneration pathways was studied. Both direct organogenesis and direct proliferation pathways were applicable to different cumin genotypes and regenerated plants were

  3. Plant Regeneration from In Vitro Cultured Hypocotyl Explants of Euonymus japonicus Cu zhi


    Adventitious shoots were successfully regenerated from hypocotyl explants of in vitro cultures of Euonymus japonicus Cu zhi. Hypocotyl slices were cultured on Murashige and Skoog (MS) and B5 basal medium supplemented with varied concentration of different plant growth-regulators, e.g., α-naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA) in combination with 6-benzylaminopurine (6-BA) and kinetin. The study showed that shoots could be directly regenerated from hypocotyl explants without the intervening callus phase; MS medium was more suitable for adventitious shoots regeneration. The ability of hypocotyls segments to produce shoots varied depending upon their position on the seedlings. The highest regeneration rate was obtained with hypocotyl segments near to the cotyledon cultured on MS basal medium supplemented with 1.5 mg L-1 6-BA and 0.05 mg L-1 NAA (63.64%). The regenerated shoots were readily elongated on the same medium as used for multiplication and rooted on half-strength MS basal medium supplemented with 1.0 mg L-1 IBA and 100 mg L-1 activated carbon. After being transferred to greenhouse conditions, 96% of the plantlets were successfully acclimatized. This regeneration system is applied for genetic transformation now.

  4. Proliferative effect of the aqueous extract of Hyptis pectinata on liver regeneration after partial hepatectomy in rats Efeito do extrato aquoso da Hyptis pectinata na regeneração hepática após hepatectomia parcial em ratos

    Gustavo Barreto Melo


    Full Text Available PURPOSE: This study was carried out to assess the effects of the aqueous extract of Hyptis pectinata leaves on liver regeneration and on serum enzymes (AST, ALT and gamma-GT after 67% partial hepatectomy in rats. METHODS: AST, ALT and gamma-GT, were determined by conventional procedures using a spectrophotometer (Model E2250-CELM. Liver regeneration was evaluated by immunohistochemical staining for proliferating cell nuclear antigen (PCNA. RESULTS:Oral pretreatment during 4 days at 100 mg/kg increased liver regeneration index. At 200 mg/kg, AST level was statistically decreased in comparison to the group submited to distilled water administration. The other enzymes assessed disclosed no difference when all groups were compared. CONCLUSION: The present study shows that the aqueous extract of Hyptis pectinata leaves contains some biological active principles that stimulate liver regeneration at 100 mg/kg and cause slight hepatic protection at 200 mg/kg.OBJETIVO: Este estudo foi realizado com o objetivo de verificar o efeito do extrato aquoso da Hyptis pectinata na regeneração hepática bem como nos níveis das enzimas séricas (AST, ALT e gama-GT após hepatectomia parcial de 67% em ratos. MÉTODOS: AST, ALT e gama-GT, foram determinadas pelo método cinético utilizando um espectrofotômetro (Modelo E2250-CELM. A regeneração hepática foi avaliada por imunohistoquímica (PCNA. RESULTADOS: O pré-tratamento oral de 100 mg/kg foi realizado durante 4 dias e causou aumento na regeneração hepática O pré-tratamento oral com 200 mg/kg diminuiu significativamente os níveis de AST quando comparado com o grupo submetido ao pré-tratamento com água destilada. As demais enzimas avaliadas não apresentaram diferenças quando comparadas entre os grupos estudados. CONCLUSÃO: O presente estudo mostra que o extrato aquoso da Hyptis pectinata, numa concentração de 100 mg/kg possui alguma atividade biológica estimulando a regeneração hepática e

  5. Periodontal regeneration.

    Ivanovski, S


    The ultimate goal of periodontal therapy is the regeneration of the tissues destroyed as a result of periodontal disease. Currently, two clinical techniques, based on the principles of "guided tissue regeneration" (GTR) or utilization of the biologically active agent "enamel matrix derivative" (EMD), can be used for the regeneration of intrabony and Class II mandibular furcation periodontal defects. In cases where additional support and space-making requirements are necessary, both of these procedures can be combined with a bone replacement graft. There is no evidence that the combined use of GTR and EMD results in superior clinical results compared to the use of each material in isolation. Great variability in clinical outcomes has been reported in relation to the use of both EMD and GTR, and these procedures can be generally considered to be unpredictable. Careful case selection and treatment planning, including consideration of patient, tooth, site and surgical factors, is required in order to optimize the outcomes of treatment. There are limited data available for the clinical effectiveness of other biologically active molecules, such as growth factors and platelet concentrates, and although promising results have been reported, further clinical trials are required in order to confirm their effectiveness. Current active areas of research are centred on tissue engineering and gene therapy strategies which may result in more predictable regenerative outcomes in the future.

  6. Efficient plant regeneration from cotyledon explants of bottle gourd (Lagenaria siceraria Standl.).

    Han, J-S; Oh, D-G; Mok, I-G; Park, H-G; Kim, C K


    Using cotyledon explants excised from seedlings germinated in vitro, an efficient plant regeneration system via organogenesis was established for bottle gourd (Lagenaria siceraria Standl.). Maximum shoot regeneration was obtained when the proximal parts of cotyledons from 4-day-old seedlings were cultured on MS medium with 3 mg/l BA and 0.5 mg/l AgNO(3) under a 16-h photoperiod. After 3-4 weeks of culture, 21.9-80.7% of explants from the five cultivars regenerated shoots. Adventitious shoots were successfully rooted on a half-strength MS medium with 0.1 mg/l IAA for 2-3 weeks. Flow cytometric analysis revealed that most of the regenerated plants derived from culture on medium with AgNO(3) were diploid.

  7. Pre-culturing of nodal explants in thidiazuron supplemented liquid medium improves in vitro shoot multiplication of Cassia angustifolia.

    Siddique, I; Abdullwahab Bukhari, N; Perveen, K; Siddiqui, I; Anis, M


    An in vitro propagation system for Cassia angustifolia Vahl. has been developed. Due to the presence of sennosides, the demand of this plant has increased manyfold in global market. Multiple shoots were induced by culturing nodal explants excised from mature plants on a liquid Murashige and Skoog [8] medium supplemented with 5-100 μM of thidiazuron (TDZ) for different treatment duration (4, 8, 12 and 16 d). The optimal level of TDZ supplemented to the culture medium was 75 μM for 12 d induction period followed by subculturing in MS medium devoid of TDZ as it produced maximum regeneration frequency (87%), mean number of shoots (9.6 ± 0.33) and shoot length (4.4 ± 0.46 cm) per explant. A culture period longer than 12 d with TDZ resulted in the formation of fasciated or distorted shoots. Ex vitro rooting was achieved when the basal cut end of regenerated shoots was dipped in 200 μM indole-3-butyric acid (IBA) for half an hour followed by their transplantation in plastic pots filled with sterile soilrite where 85% plantlets grew well and all exhibited normal development. The present findings describe an efficient and rapid plant regeneration protocol that can further be used for genetic transformation studies.

  8. MARCKS-like protein is an initiating molecule in axolotl appendage regeneration.

    Sugiura, Takuji; Wang, Heng; Barsacchi, Rico; Simon, Andras; Tanaka, Elly M


    Identifying key molecules that launch regeneration has been a long-sought goal. Multiple regenerative animals show an initial wound-associated proliferative response that transits into sustained proliferation if a considerable portion of the body part has been removed. In the axolotl, appendage amputation initiates a round of wound-associated cell cycle induction followed by continued proliferation that is dependent on nerve-derived signals. A wound-associated molecule that triggers the initial proliferative response to launch regeneration has remained obscure. Here, using an expression cloning strategy followed by in vivo gain- and loss-of-function assays, we identified axolotl MARCKS-like protein (MLP) as an extracellularly released factor that induces the initial cell cycle response during axolotl appendage regeneration. The identification of a regeneration-initiating molecule opens the possibility of understanding how to elicit regeneration in other animals.

  9. Evaluation of the new vacuum infiltration vitrification (viv) cryopreservation technique for native Australian plant shoot tips.

    Funnekotter, Bryn; Whiteley, Susan E; Turner, Shane R; Bunn, Eric; Mancera, Ricardo L


    The application of a vacuum during the incubation in cryoprotective agents such as PVS2 allows for increased penetration, reducing total incubation times required before vitrification and post-cryopreservation regeneration is achieved. This study compared a conventional droplet-vitrification protocol to the new vacuum infiltration vitrification protocol in four Australian plant species. The new vacuum infiltration vitrification applied an 80 kPa vacuum during incubations in loading solution and PVS2. Infiltration of the cryoprotective agents into shoot tips was determined by differential scanning calorimetry measuring ice formation in the thermographs comparing a range of loading solution and PVS2 incubation times. The application of the vacuum infiltration vitrification technique resulted in a significantly reduced PVS2 incubation time for cryogenic survival and regeneration for all four species, reducing the time needed to adequately protect shoot tips by half to a quarter when compared to a conventional droplet-vitrification technique.

  10. Embryoid Formation by High Temperature Treatment from Multiple Shoots of Panax ginseng1.

    Asaka, I; Li, I; Yoshikawa, T; Hirotani, M; Furuya, T


    We developed a new technology to induce embryoids by a moderate high temperature treatment from multiple shoots of PANAX GINSENG (Araliaceae). The number of formed embryoids was 10 times higher than that of untreated tissue. Normal plantlets were regenerated from the embryoids by transplanting them on a hormone-free medium. They contained ginsenosides Rb (1), Rg (1) and the other saponins as well as those of natural ginseng.

  11. Potential proliferative effect of lipopolysaccharide preconditioning on ...



    Apr 1, 2015 ... preconditioning on human umbilical cord blood-derived endothelial progenitor cells ... order to form new blood vessels and/or incorporate into existing vasculature ..... neovascularization and regeneration. Cerebrovasc. Dis.

  12. Cytological Correlation Between Flower and Vegetative Shoot Development from Immature Embryo-Derived Calli in Wheat

    WU Bi-hua; ZHENG You-liang; LUO Jian-ming


    In this paper, the traits of immature embryo culture from 45 genotypes of bread wheat were investigated in detail, and trait correlation analysis in combination with histomorphological examination was used to study the cytological origin of flower as well as the correlation between it and vegetative shoot development from the calli. The rate of floral development in the subculture was highly significantly and positively related to that of the differentiation culture, which reveals that the genetic system of floral development from immature embryo-derived calli in wheat was highly correspondent and stable. The rate of floral development was related neither to the traits in the dedifferentiation culture, nor to the vegetative shoot formation from the total induced calli, but significantly and positively related to that of the calli without leaf-like green spots in the differentiation culture. These findings indicate the partial correlation as well as differentiation between flower and vegetative shoot development. The floral development might only be associated with the genetic system controlling organ regeneration, while vegetative shoots formed from the two ways, including somatic embryogenesis and organ regeneration.

  13. Regenerator seal

    Davis, Leonard C.; Pacala, Theodore; Sippel, George R.


    A method for manufacturing a hot side regenerator cross arm seal assembly having a thermally stablilized wear coating with a substantially flat wear surface thereon to seal between low pressure and high pressure passages to and from the hot inboard side of a rotary regenerator matrix includes the steps of forming a flat cross arm substrate member of high nickel alloy steel; fixedly securing the side edges of the substrate member to a holding fixture with a concave surface thereacross to maintain the substrate member to a slightly bent configuration on the fixture surface between the opposite ends of the substrate member to produce prestress therein; applying coating layers on the substrate member including a wear coating of plasma sprayed nickel oxide/calcium flouride material to define a wear surface of slightly concave form across the restrained substrate member between the free ends thereon; and thereafter subjecting the substrate member and the coating thereon to a heat treatment of F. for sixteen hours to produce heat stabilizing growth in the coating layers on the substrate member and to produce a thermally induced growth stress in the wear surface that substantially equalizes the prestress in the substrate whereby when the cross arm is removed from the fixture surface following the heat treatment step a wear face is formed on the cross arm assembly that will be substantially flat between the ends.

  14. Regeneration efficiency based on genotype, culture condition and growth regulators of eggplant (Solanum melongena L.

    Md Abdul Muktadir


    Full Text Available Several experiments were carried out to establish an efficient regenerating protocol for cultivated eggplant varieties. Among the five varieties cultured on Murashige and Skoog (MS medium with free plant growth regulator (PGR, Nayantara performed better considering the number of shoots/explant (2.48. Considering explant types and culture conditions, better performance was observed (3.68 shoots/explant when seed germination in the dark was proceeded by bottom hypocotyl segments cultured under dark conditions. A higher rate of shoot regeneration was observed in Nayantara when cultured in Zeatin Riboside (ZR and Thidizuron (TDZ supplemented MS medium. The highest number of shoots per explant was produced on MS medium supplemented with 2.0 mg/L ZR and 0.1 mg/L indole acetic acid (6.65 shoots/explant. Proliferation and elongation of the regenerated shoots were obtained in the MS medium with free PGR. The best rooting performance was observed in MS medium supplemented with 2.0 mg/L indole butyric acid. Plantlets with well developed roots and shoots were successfully transferred to soil.

  15. Acetylcholine suppresses shoot formation and callusing in leaf explants of in vitro raised seedlings of tomato, Lycopersicon esculentum Miller var. Pusa Ruby.

    Bamel, Kiran; Gupta, Rajendra; Gupta, Shirish C


    We present experimental evidence to show that acetylcholine (ACh) causes decrease in shoot formation in leaf explants of tomato (Lycopersicon esculentum Miller var Pusa Ruby) when cultured on shoot regeneration medium. The optimum response was obtained at 10(-4) M ACh-enriched medium. ACh also causes decrease in percentage of cultures forming callus and reduces the callus mass. Inhibitors of enzymatic hydrolysis of ACh, neostigmine and physostigmine, also suppresses callogenesis and caulogenesis. On the other hand, the breakdown products of Ach, choline and acetate, do not alter the morphogenic response induced on the shoot regeneration medium. Neostigmine showed optimal reduction in shoot formation at 10(-5) M. The explants cultured on neostigmine augmented medium showed decline in the activity of ACh hydrolyzing enzyme acetylcholinesterase. ACh and neostigmine added together showed marked reduction in callus mass. These results strongly support the role of ACh as a natural regulator of morphogenesis in tomato plants.

  16. Hippo pathway effector Yap promotes cardiac regeneration.

    Xin, Mei; Kim, Yuri; Sutherland, Lillian B; Murakami, Masao; Qi, Xiaoxia; McAnally, John; Porrello, Enzo R; Mahmoud, Ahmed I; Tan, Wei; Shelton, John M; Richardson, James A; Sadek, Hesham A; Bassel-Duby, Rhonda; Olson, Eric N


    The adult mammalian heart has limited potential for regeneration. Thus, after injury, cardiomyocytes are permanently lost, and contractility is diminished. In contrast, the neonatal heart can regenerate owing to sustained cardiomyocyte proliferation. Identification of critical regulators of cardiomyocyte proliferation and quiescence represents an important step toward potential regenerative therapies. Yes-associated protein (Yap), a transcriptional cofactor in the Hippo signaling pathway, promotes proliferation of embryonic cardiomyocytes by activating the insulin-like growth factor and Wnt signaling pathways. Here we report that mice bearing mutant alleles of Yap and its paralog WW domain containing transcription regulator 1 (Taz) exhibit gene dosage-dependent cardiac phenotypes, suggesting redundant roles of these Hippo pathway effectors in establishing proper myocyte number and maintaining cardiac function. Cardiac-specific deletion of Yap impedes neonatal heart regeneration, resulting in a default fibrotic response. Conversely, forced expression of a constitutively active form of Yap in the adult heart stimulates cardiac regeneration and improves contractility after myocardial infarction. The regenerative activity of Yap is correlated with its activation of embryonic and proliferative gene programs in cardiomyocytes. These findings identify Yap as an important regulator of cardiac regeneration and provide an experimental entry point to enhance this process.

  17. Diagnostic criteria in proliferative verrucous leukoplakia: Evaluation

    García-Chías, Begoña; Casado-De La Cruz, Laura; Esparza-Gómez, Germán C.


    Objectives: to evaluate the ability of the diagnostic criteria proposed by Cerero et al in 2010 to perform an early diagnose in patients with proliferative verrucous leukoplakia. Study Design: retrospective study with patients diagnosed with leukoplakia at Oral Medicine Service at Oral Medicine and Surgery Department at Dentistry Faculty at Universidad Complutense of Madrid. Results: the criteria were applied in 116 patients, turning positive in 40 cases. Out of these, 24 (60%) had been previously diagnosed with PVL. Most frequent criteria were major criteria A and E, concerning lesion’s site and histopathology, and minor criteria b and c, concerning sex and smoking habit. Conclusions: diagnostic criteria developed by Cerero et al can be a useful tool for an early diagnose of PVL, as in 60% of the cases, the criteria would have allowed to make an early diagnose of the disease. Key words:Proliferative verrucous leukoplakia, criteria, diagnose, early. PMID:24608210

  18. Proliferative histiocytic disorders of canine skin.

    Middleton, D J


    Proliferative histiocytic disorders of canine skin present a clinical spectrum from the innocuous self-limiting solitary dermal lesion of cutaneous histiocytoma, through the recurrent deep dermal nodules of cutaneous histiocytosis to the generally fatal condition of Bernese Mountain Dogs termed systemic histiocytosis, in which visceral involvement is commonly encountered. Immunocytochemical characterization of the constituent histiocytic cells and accompanying lymphoid infiltrate using canine species specific reagents has elucidated considerably the mechanism by which these conditions exhibit their various biologic behaviours.

  19. Proliferative myositis in a patient with AIDS

    Wlachovska, B.; Deux, J.F.; Marsault, C.; Le Breton, C. [Department of Radiology, Hopital Tenon, 4 rue de la Chine, 75020, Paris (France); Abraham, B. [Department of Tropical and Infectious Diseases, Hopital Tenon, Paris (France); Sibony, M. [Department of Anatomy, Hopital Tenon, Paris (France)


    We report a case of proliferative myositis in the right biceps of a 56-year-old man with acquired immune deficiency syndrome (AIDS). Imaging methods included sonography, computed tomography and magnetic resonance imaging. The diagnosis was made by a core-cut biopsy and fine needle aspiration biopsy with immunohistochemical analysis. The lesion disappeared after 2 months without treatment. It is particularly important to determine whether intramuscular masses arising in patients with AIDS are due to an infectious or malignant process. (orig.)

  20. Shoot apical meristem maintenance: the art of a dynamic balance.

    Carles, Cristel C; Fletcher, Jennifer C


    The aerial structure of higher plants derives from cells at the tip of the stem, in the shoot apical meristem (SAM). Throughout the life of a plant, the SAM produces stem tissues and lateral organs, and also regenerates itself. For correct growth, the plant must maintain a constant flow of cells through the meristem, where the input of dividing pluripotent stem cells offsets the output of differentiating cells. This flow depends on extracellular signaling within the SAM, governed by a spatial regulatory feedback loop that maintains a reservoir of stem cells, and on factors that prevent meristem cells from differentiating prematurely. The terminating floral meristem incorporates the spatial regulation scheme into a temporal regulation pathway involving flower patterning factors.

  1. Diffuse proliferative glomerulonephritis after bone marrow transplantation.

    Suehiro, T; Masutani, K; Yokoyama, M; Tokumoto, M; Tsuruya, K; Fukuda, K; Kanai, H; Katafuchi, R; Nagatoshi, Y; Hirakata, H


    A 15-year-old boy developed nephrotic syndrome and acute renal failure 4 years after allogenic bone marrow transplantation (BMT) for lymphoid crisis of chronic myelocytic leukemia. On admission, he presented with clinical features of chronic GVHD including transient exacerbation of cholestatic liver injury. Renal biopsy showed diffuse proliferative glomerulonephritis with cellular crescents. The patient was treated with methylprednisolone pulse therapy (1 g/day, for 3 days) followed by oral prednisolone. Renal function gradually improved but nephrotic state was persistent. A second renal biopsy showed improvement of acute tubular necrosis and endocapillary proliferation and transformation of crescents into a fibrous form. After tapering of oral prednisolone, cyclophosphamide was started, which resulted in a gradual improvement of proteinuria. Several cases of nephrotic syndrome occurring after BMT have already been reported, but most cases had membranous nephropathy. In our case, renal biopsy revealed diffuse proliferative glomerulonephritis with findings of active cellular immunity, and aggressive treatment resulted in attenuation of these findings. Moreover, chronic GVHD-related liver injury was noted at the time of this episode. Our findings suggest that chronic GVHD may be complicated with diffuse proliferative glomerulonephritis through unknown cellular immune mechanism.

  2. An intrinsic microRNA timer regulates progressive decline in shoot regenerative capacity in plants.

    Zhang, Tian-Qi; Lian, Heng; Tang, Hongbo; Dolezal, Karel; Zhou, Chuan-Miao; Yu, Sha; Chen, Juan-Hua; Chen, Qi; Liu, Hongtao; Ljung, Karin; Wang, Jia-Wei


    Plant cells are totipotent and competent to regenerate from differentiated organs. It has been shown that two phytohormones, auxin and cytokinin, play critical roles within this process. As in animals, the regenerative capacity declines with age in plants, but the molecular basis for this phenomenon remains elusive. Here, we demonstrate that an age-regulated microRNA, miR156, regulates shoot regenerative capacity. As a plant ages, the gradual increase in miR156-targeted SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors leads to the progressive decline in shoot regenerative capacity. In old plants, SPL reduces shoot regenerative capacity by attenuating the cytokinin response through binding with the B-type ARABIDOPSIS RESPONSE REGULATORs, which encode the transcriptional activators in the cytokinin signaling pathway. Consistently, the increased amount of exogenous cytokinin complements the reduced shoot regenerative capacity in old plants. Therefore, the recruitment of age cues in response to cytokinin contributes to shoot regenerative competence. © 2015 American Society of Plant Biologists. All rights reserved.

  3. Current perspectives on shoot branching regulation

    Cunquan YUAN,Lin XI,Yaping KOU,Yu ZHAO,Liangjun ZHAO


    Full Text Available Shoot branching is regulated by the complex interactions among hormones, development, and environmental factors. Recent studies into the regulatory mecha-nisms of shoot branching have focused on strigolactones, which is a new area of investigation in shoot branching regulation. Elucidation of the function of the D53 gene has allowed exploration of detailed mechanisms of action of strigolactones in regulating shoot branching. In addition, the recent discovery that sucrose is key for axillary bud release has challenged the established auxin theory, in which auxin is the principal agent in the control of apical dominance. These developments increase our understan-ding of branching control and indicate that regulation of shoot branching involves a complex network. Here, we first summarize advances in the systematic regulatory network of plant shoot branching based on current information. Then we describe recent developments in the synthesis and signal transduction of strigolactones. Based on these considerations, we further summarize the plant shoot branching regulatory network, including long distance systemic signals and local gene activity mediated by strigolactones following perception of external envi-ronmental signals, such as shading, in order to provide a comprehensive overview of plant shoot branching.

  4. Lockheed P-80A Shooting Star


    Lockheed P-80A Shooting Star: The Lockheed P-80A Shooting Star was America's first fully operation jet fighter. This all-yellow example arrived at Langley in November 1946. The P-80 was used for air speed calibration and development of a tuned vibration damper.

  5. A novel combination of plant growth regulators for in vitro regeneration of complete plantlets of guar [Cyamopsis tetragonoloba (L.) Taub].

    Verma, S; Gill, K S; Pruthi, V; Dhugga, K S; Randhaw, G S


    A novel combination of plant growth regulators comprising indole-3-butyric acid (IBA), 6-benzylaminopurine (BA) and gibberellic acid (GA3) in Murashige and Skoog basal medium has been formulated for in vitro induction of both shoot and root in one culture using cotyledonary node explants of guar, (Cyamopsis tetragonoloba). Highest percentages of shoot (92%) and root (80%) induction were obtained in the medium containing (mg/L) 2 IBA, 3 BA and 1 GA3. Shoot regeneration from the cotyledonary node explants was observed after 10-15 days. Regeneration of roots from these shoots occurred after 20 to 25 days. The regenerated plantlets showed successful acclimatization on transfer to soil. This protocol is expected to be helpful in carrying out various in vitro manipulations in this economically and industrially important legume.

  6. Cryopreservation of adventitious shoot tips of Paraisometrum mileense by droplet vitrification.

    Lin, Liang; Yuan, Bin; Wang, Dandan; Lin, Weiqi


    Gesneriaceae family contains numerous species endemic to China, and many of them are listed as endangered species. There is a need for a simple and efficient method for long-term conservation of these species. The study aimed to establish an efficient procedure for cryopreserving Paraisometrum mileense, a critically endangered species endemic to Yunnan, China. Effects of sucrose concentration of preculture solution, duration of sucrose preculture, duration of plant vitrification solution 2 (PVS2) treatment, and cold acclimation on regeneration of cryopreserved adventitious shoot tips (ASTs) were assessed. Among different sucrose preculture regimes tested, preculture with 0.3M sucrose for 24h resulted in best regeneration of cryopreserved ASTs. PVS2 treatment also affected regeneration considerably with the maximum survival of ASTs after incubation in PVS2 for 90 min at 0 degrees C. With the optimised parameters, the level of shoot regeneration from cryopreserved ASTs reached 86%. No morphological abnormalities were observed during one year's growth of the plantlets developing from cryopreserved ASTs. Procedure established in this research is a promising technique for the cryopreservation of ASTs of this species.

  7. Calcium Signalling and Liver Regeneration

    Isabelle Garcin


    Full Text Available After partial hepatectomy (PH the initial mass of the organ is restored through a complex network of cellular interactions that orchestrate both proliferative and hepatoprotective signalling cascades. Among agonists involved in this network many of them drive Ca2+ movements. During liver regeneration in the rat, hepatocyte cytosolic Ca2+ signalling has been shown on the one hand to be deeply remodelled and on the other hand to enhance progression of hepatocytes through the cell cycle. Mechanisms through which cytosolic Ca2+ signals impact on hepatocyte cell cycle early after PH are not completely understood, but at least they include regulation of immediate early gene transcription and ERK and CREB phosphorylation. In addition to cytosolic Ca2+, there is also evidence that mitochondrial Ca2+ and also nuclear Ca2+ may be critical for the regulation of liver regeneration. Finally, Ca2+ movements in hepatocytes, and possibly in other liver cells, not only impact hepatocyte progression in the cell cycle but more generally may regulate cellular homeostasis after PH.

  8. Plant regeneration of Alstroemeria in vitro

    Eleonora Gabryszewska


    Full Text Available The regenerative ability of explants from various organs of Alstroemeria plants was investigated. Rhizome apical and axillary tips cultured on the Murashige and Skoog medium with BA - 2. mgl-1 and NAA - 0,5 mgl-1 were the best among the tissue tested as initial explants. Five weeks after isolation the rhizome with 1-4 upright growing shoots were obtained. The types of rhizome explants influenced development and growth of lateral rhizomes and upright growing shoots. There were no significant differences in number of roots formed on various kind of rhizome explants. Rooting was strongly influenced by NAA. Subapical segments of vegetative stem, segments of flower pedicels and parts of ovary did not regenerate rhizome or roots but occasionally callus was formed on the medium with kinetin - 2 mgl-1 and NAA - 2 mgl-1. Segments excised from vegetative stem sporadically developed roots on the medium with NAA or IBA in concentrations 3 and 9 mgl-1.

  9. Growth and carbohydrate status of coppice shoots of hybrid poplar following shoot pruning.

    Tschaplinski, T J; Blake, T J


    Fifteen, 1-year-old Populus maximowiczii Henry x P. nigra L. 'MN9' trees were decapitated and allowed to sprout. After 8 weeks, all had 6 to 10 coppice shoots. All shoots, except the tallest (dominant) shoot, were removed from five of the trees (pruned treatment), and shoot growth, gas exchange and carbohydrate status were compared in the pruned and unpruned trees. Although photosynthetic rate of recently mature leaves of pruned trees was approximately 50% greater than that of leaves on the dominant shoot of unpruned trees, and the dry weight of leaves of pruned trees was 37% greater than that of the leaves on the dominant shoot of unpruned trees, the shoot dry matter relative growth rate did not differ between treatments. Concentrations of water-soluble carbohydrates and starch in the uppper stem and leaves of the dominant shoot were similar in pruned and unpruned trees. However, relative to that of the dominant shoot in unpruned trees, the lower stem in pruned trees was depleted in both soluble carbohydrates and starch. Starch deposition, assessed as the quantity of (14)C-starch in tissues 24 h after a fully expanded source leaf was labeled with (14)CO(2), was 3.9 times greater in roots of pruned trees than in roots of unpruned trees. We conclude that early removal of all but the dominant shoot reduces the carbohydrate status of the roots and the lower portion of the stem by eliminating the excised shoots as a source of photosynthate.

  10. Novel technique for scaling up of micropropagated Ruta graveolens shoots using liquid culture systems: a step towards commercialization.

    Diwan, Renuka; Malpathak, Nutan


    Wide applications of Ruta graveolens L. in pharmaceutical industry has led to increased interest in large-scale plant production, with emphasis on use of in vitro cultures. Earlier reports describe use of in vitro germinated seedlings for raising shoot cultures and not regeneration. There is only a single regeneration protocol of R. graveolens; however, it employs conventional labour intensive techniques deterring automation. The aim of present investigation was to establish a cost effective protocol for large-scale plant production. We report for the first time a one-step protocol with improved regeneration efficiency for multiple shoots induction employing liquid culture systems. Effect of polyamines (putrescine and spermine) on growth and furanocoumarin was studied. Addition of spermine enhanced the number of multiple shoots formed (2.5-fold) and reduced the time taken by half. Spermine addition resulted in 1.47-fold in furanocoumarin production. The selected shoot line, RS2 was successfully scaled up to 5L in culture vessels, with 1.53-fold increase in biomass without affecting the productivity of these cultures. This proves to be a commercially feasible alternative to bioreactors for large-scale biomass and furanocoumarin production.

  11. Survival, regeneration and leaf biomass changes in woody plants following spring burns in Burkea africana—Ochna pulchra Savanna*

    M. C. Rutherford


    Full Text Available Effects of two intensities of spring burn on various aspects of woody plants of a Burkea africana—Ochna pulchra Savanna after one growth season are given. Mortality of woody plants was very low with, for example, that of individuals of Ochna pulchra being between 1 and 5%. Some species where the above-ground parts were often burned away completely, as in  Grewia flavescens, no mortality of individuals occurred. Basal regeneration shoot mass was found to depend parabolically on plant height while the ratio of leaf to twig mass in basal shoot regeneration varied inversely with plant height in  Ochna pulchra. The ability of  Ochna pulchra plants to produce new basal shoots appeared to not only depend on size of the plant but also on the number of basal shoots present prior to the fire. In live Ochna pulchra plants basal regeneration shoot biomass per individual was found to increase exponentially with greater reduction in canopy leaf biomass. This relation was also affected by possible direct heat effects. Basal shoot regeneration mass was found to vary greatly with species and varied from 0,7 g/individual for  Dichapetalum cymosum to 285,6 g/individual for Euclea natalensis. There was a clear tendency for non-suffrutex shrub species to have greater mean basal regeneration shoot mass per plant than that of most tree species. There was a compensatory effect in  Ochna pulchra between number and size of basal regeneration shoots. Standing dead woody plant individuals (before the burn were either felled by fire or apparently unaffected by fire and there was no selectivity by species. Results of the present study are generally supported by other work on the effects of fire in savanna and some other vegetation types.

  12. Proline and Glutamine Improvein vitro Callus Induction and Subsequent Shooting in Rice

    Bhausaheb PAWAR; Prashant KALE; Jyoti BAHURUPE; Ashok JADHAV; Anil KALE; Sharad PAWAR


    This study was conducted to evaluate the effects of proline and glutamine onin vitro callus induction and subsequent regeneration and to develop a reproducible and highly efficient plant regeneration protocol in four ricegenotypes, viz. Pawana, Jaya, Indrayani and Ambemohar. Considerable variation in response to plant growth regulators and amino acid supplements used was observed in all the four genotypes. Medium supplemented with proline and glutamine was shown to be superior to medium without proline and glutamine. The best callusing from mature embryo was observed on Murashige and Skoog (MS) medium supplemented with 2.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D), 500 mg/L proline and 500 mg/L glutamine. Shoot induction was higher in the callus obtained from medium supplemented with 500 mg/L proline and 500 mg/L glutamine. The highest shoot regeneration frequency (83.2%) was observed on MS medium with 2.0 mg/L benzylaminopurine, 0.5 mg/L 1-naphthaleneacetic acid, 500 mg/L proline, and 500 mg/L glutamine in the callus obtained from MS medium supplemented with 2.0 mg/L 2,4-D, 500 mg/L proline and 500 mg/L glutamine. Among the four genotypes, Pawana has the highest regeneration efficiency (83.2%), whereas the regeneration efficiency of the rest three rice genotypes was in the range of 32.0% to 72.3%. This optimized regeneration protocol can be efficiently used forAgrobacterium mediated genetic transformation in rice.

  13. Value addition to bamboo shoots: a review.

    Choudhury, Debangana; Sahu, Jatindra K; Sharma, G D


    Bamboo shoot forms a traditional delicacy in many countries. Being low in fat content and high in potassium, carbohydrate, dietary fibres, Vitamins and active materials, bamboo shoots are consumed in raw, canned, boiled, marinated, fermented, frozen, liquid and medicinal forms. Although the fresh bamboo shoots of species like Dendraocalamus giganteus are healthier and nutritionally rich, the young shoots, after fortification, can be consumed by processing into a wide range of food products with longer shelf-life and better organoleptic qualities. However, the consumption pattern of bamboo shoots in most of the countries is traditional, non-standardized, seasonal and region-specific with little value addition. Therefore, there exists a great opportunity, especially for the organized food processing sectors to take up the processing of bamboo shoot-based food products in an organized manner. The present article gives an insight into the global scenario of bamboo shoot-based food products and their consumption pattern, the quality attributes, and the opportunities for value addition along with future prospects in view of international food safety, security and nutrition.

  14. Fried Bamboo Shoots with Salted Vegetables


    Ingredients: 250 grams of canned bamboo shoots; 75 grams of salted potherb mustard leaves; 5 grams of cooking wine, 1 gram of salt and 500 grams of vegetable oil (15 grams will be consumed). MSG to taste. Directions: 1. Chop the bamboo shoots into rectangles 4 centimeters by 1.65 centimeters. Marinate the bamboo shoots in salt and cooking wine. Clean the salted potherb mustard leaves (or any other kind of vegetable leaves) with hot water and chop into 3.5-centimeter segments.


    Loeb, J


    1. In Bryophyllum calycinum two apical leaves suppress the shoot formation in all the dormant buds situated basally from the leaf; one apical leaf suppresses the shoot formation in the basal buds situated in the same half of the stem where the leaf is, and, if one-half of the petiole of such a leaf is removed, the growth of basal buds in one quadrant of the stem is suppressed. 2. This inhibitory influence of a leaf upon shoot formation in the basal part of a stem is diminished or disappears when the mass of the leaf is reduced below a certain limit. 3. The inhibitory influence of an apical leaf upon the growth of shoots in horizontally suspended stems is greater when the leaf is on the upper than when it is on the lower side of the stem. 4. All these facts suggest the possibility that the inhibitory influence of the leaf upon shoot formation is due to inhibitory substances secreted by the leaf and carried by the sap from the leaf towards the base of the stem. 5. An apical leaf accelerates root formation in the basal part of a stem and this accelerating effect increases with the mass of the leaf. 6. This inhibitory influence of a leaf upon shoot formation and the favoring influence upon root formation in the more basally situated parts of the stem is one of the factors determining the polar character of regeneration.

  16. Human stem cells and articular cartilage regeneration.

    Inui, Atsuyuki; Iwakura, Takashi; Reddi, A Hari


    The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES) cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS) cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  17. Human Stem Cells and Articular Cartilage Regeneration

    A. Hari Reddi


    Full Text Available  The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  18. Regeneration and growth rates of allofragments in four common stream plants

    Riis, Tenna; Madsen, Tom Vindbæk; Sennels, R. S. H.


    Colonisation by stream plants occurs to a large extent from simple stem fragments. Allofragments are stem fragments formed by mechanical breakage. We studied regeneration, colonisation, and growth rates in four common stream plants: Elodea canadensis Michx., Myriophyllum spicatum L., Potamogeton...... perfoliatus L. and Ranunculus baudotii x pseudofluitans. The objectives of this study were to determine (1) if shoots with an apical tip have higher regeneration (growth of new shoots and rhizomes from allofragments) and colonisation (root attachment in sediment) abilities and higher relative growth rates...

  19. Tissue Culture Technology for Populus × euramericana Hybrids: Effect of Genotype on in Vitro Regeneration


    In order to select a suitable genotype for the studies on genetic transformation, the difference among three genotypes (DN04-18, DN04-25 and DN04-26) of Populus × euramericana (Populus deltoides × P. nigra) in terms of shoot regeneration was investigated in this paper. An efficient in vitro micropropagation method was successfully established for genotype DN04-18. The high frequency shoot regeneration (90.0%) from leaf discs was obtained in genotype DN04-18 on the modified Murashige and Skoog (mMS) medium w...

  20. Plant regeneration from hypocotyl protoplasts of winter oilseed rape (Brassica napus L.

    Wacław Orczyk


    Full Text Available Protoplasts were isolated from hypocotyls of six breeding lines and two cultivars of winter oilseed rape (B. napus L.. Under presented culture conditions almost all of the protoplasts regenerated cell walls. Division frequency depended on the genotype and was from 50% to 64%. Shoot regeneration (also depended on the genotype was induced with the frequency of 3.6% (for cv Bolko on the medium containing IAA (0.1 mg•dm-3, zeatin (0.5 mg•dm-3 and BAP (0.5 mg•dm-3 . All shoots were rooted on MS basal medium supplemented with sucrose 30 g•dm-3.

  1. Effects of antibiotics on plantlet regeneration via organogenesis in Populus euphratica

    Ding Xia; Chen Xiao-yang; Li Wei; Du Zhi-yan


    Four antibiotics, kanamycin, geneticin, carbenicillin and cefotaxime, were evaluated for their effect on the regeneration of adventitious buds, shoot differentiation, rooting from regenerated shoots of Populus euphratica as well as on their control of Agrobacterium-mediated transformations. Results showed that the optimum concentration ranges of kanamycin and geneticin were 15-20 and 10-15 mg·L-1 at the stage of transgenic plantlet selection. The inhibitory effects of cefotaxime and carbenicillin varied among different genotypes of Agrobacterium. The inhibition of cefotaxime on Agrobacterium C58 was stronger than that of carbenicillin.LBA4404 and their optimum concentrations were both 150 mg·L-1.


    I Gusti Ngurah Agung Cahya Prananta


    Full Text Available The effectiveness of  jump-shoot technique step jump shoot and still jump shoot in a game is still questionable,  because many different assumptions arise. One opinion stated that step jump shoot was more effective and the other stated that and still jump shoot was more efective. Therefore it is necessary to do research on the analysis of the results of step jump shoot and and still jump shoot to improve the accuracy of shooting in a basketball. The experimental research had been conducted on 20samples of people whowere selected randomly from the men's basketball club of the Faculty of Physical Educationand Health of Teacher Training Institute PGRI Bali. Samples were divided into two groups each  consisting of 10 people. Group I was given training step  jump shoot four sets of 10 reps  and Group II training still jump shoot four sets of 10 reps. The data before and after treatment were tested by SPSS computer program. The data were normally distributed and homogeneous so further tested using pairedt-test to compare the average values?? before and after training between each group, while the independent t-test was used to determine differences in mean values?? between the two groups. Paired t-test resulted the obtained data were significantly increased in both treatment groups p=0,001 in Group I and p=0,000 in Group II (p <0.05. Results of independent t-test found that both groups before training did not differ significantly p=0,926 (p>0.05 and after training both groups equally improve the accuracy of shooting because p=0,133 (p>0.05. It was concluded that botht raining improved the shooting accuracy and there was no difference between the effect of step jumps hoot and still jump shoot toward the shooting accuracy. It was suggested to improve the shooting accuracy in basketball used step jump shoot training and still jump shoot training four sets of 10 reps with a training frequency of 4 times a week for 6 weeks

  3. Effect of gelling agents on shoot growth and multiple shoot formation of mangosteen

    Sompong Te-chato


    Full Text Available Apomict seeds of mangosteen were cultured as a whole or half seed on MS medium supplemented with 5 mg/l 6-benzyladenine (BA. The medium was solidified with various gelling agents. After culture for 2 months, multiple shoot formation, morphological and physiological characters of the shoot were investigated. The results revealed that 1.5% agarose gave the highest seed forming shoot (98% and number of shoots per culture seed (20.7. Wounding the seed by sectioning into half promoted higher callus formation (47-88% in all gelling agents. Phytagel (0.17% resulted in the highest callus formation (100% and hyperhydric shoots (11-31%. Those shoots produced translucent, thin and brittle leaves and stems, and malformed stoma. Those leaves had the lowest content of chlorophyll a, b and total chlorophyll.

  4. Contagion in Mass Killings and School Shootings

    Towers, Sherry; Gomez-Lievano, Andres; Khan, Maryam; Mubayi, Anuj; Castillo-Chavez, Carlos


    ... the seeds of ideation in at-risk individuals to commit similar acts. Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings...

  5. Integrins are required for tissue organization and restriction of neurogenesis in regenerating planarians.

    Seebeck, Florian; März, Martin; Meyer, Anna-Wiebke; Reuter, Hanna; Vogg, Matthias C; Stehling, Martin; Mildner, Karina; Zeuschner, Dagmar; Rabert, Franziska; Bartscherer, Kerstin


    Tissue regeneration depends on proliferative cells and on cues that regulate cell division, differentiation, patterning and the restriction of these processes once regeneration is complete. In planarians, flatworms with high regenerative potential, muscle cells express some of these instructive cues. Here, we show that members of the integrin family of adhesion molecules are required for the integrity of regenerating tissues, including the musculature. Remarkably, in regenerating β1-integrin RNAi planarians, we detected increased numbers of mitotic cells and progenitor cell types, as well as a reduced ability of stem cells and lineage-restricted progenitor cells to accumulate at wound sites. These animals also formed ectopic spheroid structures of neural identity in regenerating heads. Interestingly, those polarized assemblies comprised a variety of neural cells and underwent continuous growth. Our study indicates that integrin-mediated cell adhesion is required for the regenerative formation of organized tissues and for restricting neurogenesis during planarian regeneration.

  6. [Genetic regulation of plant shoot stem cells].

    Al'bert, E V; Ezhova, T A


    This article describes the main features of plant stem cells and summarizes the results of studies of the genetic control of stem cell maintenance in the apical meristem of the shoot. It is demonstrated that the WUS-CLV gene system plays a key role in the maintenance of shoot apical stem cells and the formation of adventitious buds and somatic embryos. Unconventional concepts of plant stem cells are considered.

  7. Rapid plant regeneration and analysis of genetic fidelity of in vitro derived plants of Chlorophytum arundinaceum Baker--an endangered medicinal herb.

    Lattoo, S K; Bamotra, S; Sapru Dhar, R; Khan, S; Dhar, A K


    An efficient in vitro multiplication system via multiple shoot bud induction and regeneration has been developed in Chlorophytum arundinaceum using shoot crown explants. Optimum regeneration frequency (87%) and desirable organogenetic response in the form of de novo organized multiple shoot buds without an intervening callus phase was obtained on Murashige and Skoog's (MS) minimal organics medium containing 3% sucrose (w/v) supplemented with 4 x 10(-6) M Kn and 2 x 10(-6) MIBA. Axenic secondary explants with multiple shoot buds on subculturing elicited best response with 1 x 10(-5) M Kinetin (Kn) and 5 x 10(-6) M indole-3-butyric acid (IBA) giving rise to an average of 18.74 shoots per culture with mean shoot length of 7.6 cm +/- 1.73. Varying molar ratios of either Kn/IBA or Kn/NAA revealed statistically significant differences in the regeneration frequencies among the phytohormone treatments. It was observed that the shoot bud differentiation and regeneration was influenced by the molar ratios of cytokinins/auxin rather than their relative concentrations. Healthy regenerated shoots were rooted in half strength MS basal medium containing 3% sucrose (w/v) supplemented with 5 x 10(-6) M IBA. Following simple hardening procedures, rooted plantlets, were transferred to soil-sand (1:1; v/v) with more than 90% success. Genetic fidelity was assessed using random amplified polymorphic DNA (RAPD), karyotype analysis and meiotic behaviour of in vitro and in vivo plants. Five arbitrary decamers displayed same banding profile within all the micropropagated plants and in vivo explant donor. The cytological and molecular analysis complemented and compared well and showed no genomic alterations in the plants regenerated through shoot bud differentiation. High multiplication frequency, molecular, cytological and phenotypic stability ensures the efficacy of the protocol developed for the production and conservation of this important endangered medicinal herb.

  8. Direct regeneration of Periwinkle (Catharanthus roseus via node explants culture and different combinations of plant growth regulators

    M. Talebi


    Full Text Available Periwinkle (Catharanthus roseus L., Apocynaceae contains more than 130 different terpenoid indole alkaloids (TIAs, of which two dimeric alkaloids, Vinblastine and Vincristine, have antineoplastic activity and are useful in treatment of various cancers. Specific production of some alkaloids in differentiated tissues such as leaf and stem led to use direct regeneration of explants in order to increase the production of these important alkaloids in the plant. In this research, 30 combinations of plant growth regulators and activated charcoal were used in MS media for direct regeneration of node explants. Application of BAP in media containing 1 g/l activated charcoal showed the best direct regeneration of node explants and shoot proliferation. Although application of activated charcoal is necessary for periwinkle growth in media due to many phenolic compounds, but it has negative effects on adsorption of plant growth regulators and consequently reduce shoot proliferation. Therefore, it seems that 1 g/l activated charcoal is an appropriate concentration for preparing shoot proliferation media. In addition, transporting regenerated shoots to culture media containing NAA resulted in increasing shoot length. Proliferated shoots rooted in media without PGR and with 2 g/l activated charcoal and acclimated with environmental conditions after transferring to the soil.

  9. Optimization of in vitro and ex vitro regeneration and micromorphological studies in Basella alba L.

    Shekhawat, Mahipal S; Manokari, M


    The optimum concentrations of the plant hormones for in vitro regeneration and subsequent effect of auxins on rooting (in vitro and ex vitro) of shoots of Basella alba L. have been investigated in present study. Nodal shoot segments were used as explants to initiate the cultures. The bud breaking from explants was observed within 1 week of incubation on agar gelled Murashige and Skoog's (MS) medium. Multiple axillary shoots (7.30 ± 0.56 shoots per explant) were induced on MS medium supplemented with 2.0 mg/L 6-benzylaminopurine (BAP). The shoots were multiplied (maximum 17.10 ± 0.44 shoots per explant) on the same medium fortified with 0.5 mg/L each of BAP and Kin (Kinetin) +0.1 mg/L IAA. These shoots were excised and rooted in vitro (10.73 ± 0.92 roots per shoot) on half-strength MS medium augmented with 2.0 mg/L indole-3 butyric acid (IBA). Hundred percentage success rates have been achieved by ex vitro rooting of the in vitro regenerated shoots with IBA at 300 mg/L. The in vitro and ex vitro rooted shoots were acclimatized in greenhouse and subsequently transferred to the natural field conditions where 100 % survival rate was reported. The ex vitro rooting method was found more advantageous than in vitro rooting in terms of time, energy and survival percentage of B. alba. A comparative foliar micromorphological study of B. alba was conducted to understand the micromorphological changes in plants while shifting from in vitro to the in vivo conditions in terms of variations in stomatal index, venation pattern and vein density, and the arrangement of crystals. The study could help in understanding the response of in vitro raised plants towards in vivo environment.

  10. Body linear traits for identifying prolific goats

    Avijit Haldar


    Full Text Available Aim: The present study was conducted on prolific goat breed to identify body linear type traits that might be associated with prolificacy trait in goats. Materials and Methods: Two-stage stratified random sample survey based data were collected from 1427 non-pregnant goats with the history of single, twin and triplet litter sizes (LZ between January 2008 to February 2011 for 3 years in 68 villages located in East and North East India. Data on sixteen body linear traits were analyzed using logistic regression model to do the step-wise selection for identifying the body linear traits that could determine LZ. An average value for each identified body linear trait was determined for classifying the goats into three categories: Goats having the history of single LZ, goats having the history of twin LZ and goats having the history of triplet LZ. Results: The LZ proportions for single, twin and triplet, were 29.50, 59.14 and 11.36%, respectively, with the prolificacy rate of 181.85% in Indian Black Bengal goats. A total of eight body linear traits that could determine LZ in prolific goats were identified. Heart girth (HG measurement (>60.90 cm, paunch girth (PG (>70.22 cm, wither height (WH (>49.75 cm, neck length (>21.45 cm, ear length (>12.80 cm and distance between trochanter major (DTM bones (>12.28 cm, pelvic triangle area (PTA (>572.25 cm2 and clearance at udder (CU (>23.16 cm showed an increase likelihood of multiple LZ when compared to single LZ. Further, HG measurement (>62.29 cm, WH (>50.54 cm, PG (>71.85 cm and ear length (>13.00 cm, neck length (>22.01 cm, PTA (>589.64 cm2, CU (>23.20 cm and DTM bones (>12.47 cm were associated with increased likelihood of triplet LZ, when compared with that of twin LZ. Conclusion: HG measurement was the best discriminating factor, while PG, neck length, DTM bones, CU, PTA, WH and ear length measurements were other important factors that could be used for identifying prolific goats to achieve economic

  11. High-frequency in vitro plantlet regeneration from apical bud as a novel explant of Carum copticum L.

    Mansoureh Salehi; Bahman Hosseini; Zohreh Jabbarzadeh


    Objective: To develop an in vitro regeneration system to increase the recovery of Carum copticum L. plantlets as a part of developing a metabolic engineering program.Methods:3-acetic acid and indole butyric acid on direct shoot regeneration and rooting of ajowan from apical bud explants were assessed. All explants were cultured on Murashige and Skoog (MS) medium supplemented with different combinations of 6-benzyl amino purine (BAP) (0, 2.2, 4.4, 8.8µ The efficacy of different concentrations and combinations of 6-benzyladenine, indole-Results: The maximum shoot regeneration frequency (97.5%) and the highest number of shoots produced from apical buds (34 shoots per explant) were obtained on MS medium fortified with BAP (4.4 µmol/L) and IAA (0.5 µmol/L). Low shoot regeneration frequency was observed in BAP free treatments. The effects of different strengths of MS medium and various concentrations of IAA and indole-3- butyric acid on rooting rate, length and average number of roots were also investigated. Application of indole-3- butyric acid (6 µmol/L) in full-strength MS medium, was more effective than IAA and resulted in highest shoot regeneration frequency with the rooting rate of 100% and highest mean number of roots per shoot (41.8). The rooted plantlets were acclimatized successfully in greenhouse conditions with a survival rate of 90%. mol/L) and indole-3-acetic acid (IAA) (0, 0.5, 1.1, 2.2 µmol/L). Conclusion: In this study, a simple and reliable regeneration and acclimatization protocol for Carum copticum has been presented. This protocol can be found very advantageous for a variety of purposes, including mass multiplication of Carum species, medicinal plant breeding studies and transgenic plant production.

  12. Induction of shoot buds, multiplication and plantlet formation in seedling explants of bell pepper (Capsicum annuum L. cv. Bryza in vitro

    Andrzej Gatz


    Full Text Available In vitro shoot bud induction and multiplication as well as plantlets formation from different parts of 21-d old seedlings (shoot tip, cotyledonary node, distal part of cotyledon, acropetal section of hypocotyl of Capsicum annuum L., cv. Bryza were compared. During 4 weeks of primary explant culture on initiation media, first shoot bud primordia appeared; they reminded leaf primordia and subsequently some of them underwent enlargement, some developed into leaves and leaf-like structures (mainly on cotyledon explants. The highest number of shoot bud primordia was noted on cotyledonary node explants, but they were smaller than those on the remaining types of the explants. The best response of shoot regeneration showed cotyledon explants on which most of shoot buds were formed in each from four treated passages. From shoot buds on elongation media after 4 weeks of culture rooted rosettes of leaves were achieved, and the extension of the culture time to eight weeks without subculture caused that the rosettes developed into plantlets. Throughout four successive passages plantlets were obtained from cotyledon and shoot tip explants.

  13. Active magnetic regenerator

    Barclay, John A.; Steyert, William A.


    The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.

  14. Helping the Retina Regenerate

    ... Briefs > Helping the retina regenerate Helping the retina regenerate NEI Audacious Goals Initiative report outlines strategies to replace or reprogram neurons in the retina News Brief 03/30/17 ...

  15. Localization of QTLs for in vitro plant regeneration in tomato

    Nuez Fernando


    Full Text Available Abstract Background Low regeneration ability limits biotechnological breeding approaches. The influence of genotype in the regeneration response is high in both tomato and other important crops. Despite the various studies that have been carried out on regeneration genetics, little is known about the key genes involved in this process. The aim of this study was to localize the genetic factors affecting regeneration in tomato. Results We developed two mapping populations (F2 and BC1 derived from a previously selected tomato cultivar (cv. Anl27 with low regeneration ability and a high regeneration accession of the wild species Solanum pennellii (PE-47. The phenotypic assay indicated dominance for bud induction and additive effects for both the percentage of explants with shoots and the number of regenerated shoots per explant. Two linkage maps were developed and six QTLs were identified on five chromosomes (1, 3, 4, 7 and 8 in the BC1 population by means of the Interval Mapping and restricted Multiple QTL Mapping methods. These QTLs came from S. pennellii, with the exception of the minor QTL located on chromosome 8, which was provided by cv. Anl27. The main QTLs correspond to those detected on chromosomes 1 and 7. In the F2 population, a QTL on chromosome 7 was identified on a similar region as that detected in the BC1 population. Marker segregation distortion was observed in this population in those areas where the QTLs of BC1 were detected. Furthermore, we located two tomato candidate genes using a marker linked to the high regeneration gene: Rg-2 (a putative allele of Rg-1 and LESK1, which encodes a serine/threonine kinase and was proposed as a marker for regeneration competence. As a result, we located a putative allele of Rg-2 in the QTL detected on chromosome 3 that we named Rg-3. LESK1, which is also situated on chromosome 3, is outside Rg-3. In a preliminary exploration of the detected QTL peaks, we found several genes that may be related

  16. Diagnostic criteria in proliferative verrucous leukoplakia: evaluation.

    García-Chías, Begoña; Casado-De La Cruz, Laura; Esparza-Gómez, Germán-Carlos; Cerero-Lapiedra, Rocío


    to evaluate the ability of the diagnostic criteria proposed by Cerero et al in 2010 to perform an early diagnose in patients with proliferative verrucous leukoplakia. retrospective study with patients diagnosed with leukoplakia at Oral Medicine Service at Oral Medicine and Surgery Department at Dentistry Faculty at Universidad Complutense of Madrid. the criteria were applied in 116 patients, turning positive in 40 cases. Out of these, 24 (60%) had been previously diagnosed with PVL. Most frequent criteria were major criteria A and E, concerning lesion's site and histopathology, and minor criteria b and c, concerning sex and smoking habit. diagnostic criteria developed by Cerero et al can be a useful tool for an early diagnose of PVL, as in 60% of the cases, the criteria would have allowed to make an early diagnose of the disease.

  17. Clues to prolific productivity among prominent scientists.

    Kantha, S S


    In a survey based on the biographical sketches, obituary notes and eulogies of notable scientists, eight were identified as belonging to an elite group, having authored more than 1000 research publications, which include books, monographs and patents. They were, in chronological order, Thomas Alva Edison, Paul Karrer, Margaret Mead, Giulio Natta, Hans Selye, Herbert C Brown, Tetsuji Kametani and Carl Djerassi. Among these, Karrer, Natta and Brown were Nobelists in chemistry. Four criteria which can be identified as clues to their prolific productivity are, 1) enthusiasm for compulsive work and eccentric life style, 2) physical and/or environmental handicap, 3) pioneering efforts in a new research field, and 4) selection of research area, predominantly organic chemistry.

  18. Cell walls as a stage for intercellular communication regulating shoot meristem development

    Toshiaki eTameshige


    Full Text Available Aboveground organs of plants are ultimately derived/generated from the shoot apical meristem (SAM, which is the proliferative tissue located at the apex of the stem. The SAM contains a population of stem cells that provide new cells for organ/tissue formation. The SAM is composed of distinct cell layers and zones with different properties. Primordia of lateral organs develop at the periphery of the SAM. The shoot apex is a dynamic and complex tissue, and as such intercellular communications among cells, layers and zones play significant roles in the coordination of cell proliferation, growth and differentiation to achieve elaborate morphogenesis. Recent findings have highlighted the importance of a number of singling molecules acting in the cell wall space for the intercellular communication, including classic phytohormones and secretory peptides. Moreover, accumulating evidences reveal that cell wall properties and their modifying enzymes modulate hormone actions. In this review, we overview how behaviors of singling molecules and changes of cell wall properties are integrated for the shoot meristem regulation.


    Loeb, J


    1. Quantitative proof is furnished that all the material available for shoot and root formation in an isolated leaf of Bryophyllum calycinum flows to those notches where through the influence of gravity or by a more abundant supply of water growth is accelerated. As soon as the acceleration of growth in these notches commences, the growth of shoots and roots in the other notches which may already have started ceases. 2. It had been shown in a preceding paper that the regeneration of an isolated piece of stem may be and frequently is in the beginning not markedly polar, but that after some time the growth of all the roots except those at the base and of all the shoots except those at the apex is suppressed. This analogy with the behavior of regeneration in a leaf in which the growth in one set of notches is accelerated, suggests that in an isolated stem a more rapid growth is favored at the extreme ends (probably by a block of the sap flow at the extreme ends) and that when this happens the total flow of ascending sap goes to the most apical buds and the total flow of the descending sap goes to the most basal roots. As soon as this occurs, the growth of the other roots and shoots is suppressed.

  20. Organ and plantlet regeneration of Menyanthes trifoliata through tissue culture

    Urszula Adamczyk-Rogozińska


    Full Text Available The conditions for the regeneration of plants through organogenesis from callus tissues of Menyanthes trifoliata are described. The shoot multiplication rate was affected by basal culture media, the type and concentration of cytokinin and subculture number. The best response was obtained when caulogenic calli were cultured on the modified Schenk and Hildebrandt medium (SH-M containing indole-3-acetic acid (IAA 0,5 mg/l and 6-benzyladenine (BA 1 mg/l or zeatin (2 mg/l. Under these conditions ca 7 shoots (mostly 1 cm or more in length per culture in the 5th and 6th passages could be developed. In older cultures (after 11-12 passages there was a trend for more numerous but shorter shoot formation. All regenerated shoots could be rooted on the SH-M medium supplemented with 0.5 mg/l IAA within 6 weeks; 80% of in vitro rooted plantlets survived their transfer to soil.

  1. A Molecular Framework for the Embryonic Initiation of Shoot Meristem Stem Cells.

    Zhang, Zhongjuan; Tucker, Elise; Hermann, Marita; Laux, Thomas


    The establishment of pluripotent stem cells is a key event during plant and animal embryogenesis, but the underlying mechanisms remain enigmatic. We show that in the flowering plant Arabidopsis thaliana, expression of the shoot meristem stem cell marker CLV3 becomes detectable in transition stage embryos. Surprisingly, the key regulator of stem cell homeostasis WUSCHEL (WUS) is expressed but dispensable for stem cell initiation. Rather, the WUS paralog WOX2, a regulator of embryo patterning initiated in the zygote, functions in this process by shielding stem cell progenitors from differentiation. WOX2 upregulates HD-ZIP III transcription factors required for shoot identity and balances cytokinin versus auxin hormone pathways, revealing that classical plantlet regeneration procedures recapitulate the natural induction mechanism. Our findings link transcriptional regulation of early embryo patterning to hormonal control of stem cell initiation and suggest that similar strategies have evolved in plant and animal stem cell formation. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Shooting Mechanisms in Nature: A Systematic Review.

    Aimée Sakes

    Full Text Available In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these mechanisms fulfill.We systematically searched the literature using Scopus and Web of Knowledge to retrieve articles about solid projectiles that either are produced in the body of the organism or belong to the body and undergo a ballistic phase. The shooting mechanisms were categorized based on the energy management prior to and during shooting.Shooting mechanisms were identified with projectile masses ranging from 1·10-9 mg in spores of the fungal phyla Ascomycota and Zygomycota to approximately 10,300 mg for the ballistic tongue of the toad Bufo alvarius. The energy for shooting is generated through osmosis in fungi, plants, and animals or muscle contraction in animals. Osmosis can be induced by water condensation on the system (in fungi, or water absorption in the system (reaching critical pressures up to 15.4 atmospheres; observed in fungi, plants, and animals, or water evaporation from the system (reaching up to -197 atmospheres; observed in plants and fungi. The generated energy is stored as elastic (potential energy in cell walls in fungi and plants and in elastic structures in animals, with two exceptions: (1 in the momentum catapult of Basidiomycota the energy is stored in a stalk (hilum by compression of the spore and droplets and (2 in Sphagnum energy is mainly stored in compressed air. Finally, the stored energy is transformed into kinetic energy of the projectile using a catapult mechanism delivering up to 4,137 J/kg in the osmotic shooting mechanism in cnidarians and 1,269 J/kg in the muscle-powered appendage strike of the mantis shrimp Odontodactylus scyllarus. The launch accelerations range from 6.6g in the frog Rana pipiens to 5,413,000g in

  3. Shooting Mechanisms in Nature: A Systematic Review.

    Sakes, Aimée; van der Wiel, Marleen; Henselmans, Paul W J; van Leeuwen, Johan L; Dodou, Dimitra; Breedveld, Paul


    In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these mechanisms fulfill. We systematically searched the literature using Scopus and Web of Knowledge to retrieve articles about solid projectiles that either are produced in the body of the organism or belong to the body and undergo a ballistic phase. The shooting mechanisms were categorized based on the energy management prior to and during shooting. Shooting mechanisms were identified with projectile masses ranging from 1·10-9 mg in spores of the fungal phyla Ascomycota and Zygomycota to approximately 10,300 mg for the ballistic tongue of the toad Bufo alvarius. The energy for shooting is generated through osmosis in fungi, plants, and animals or muscle contraction in animals. Osmosis can be induced by water condensation on the system (in fungi), or water absorption in the system (reaching critical pressures up to 15.4 atmospheres; observed in fungi, plants, and animals), or water evaporation from the system (reaching up to -197 atmospheres; observed in plants and fungi). The generated energy is stored as elastic (potential) energy in cell walls in fungi and plants and in elastic structures in animals, with two exceptions: (1) in the momentum catapult of Basidiomycota the energy is stored in a stalk (hilum) by compression of the spore and droplets and (2) in Sphagnum energy is mainly stored in compressed air. Finally, the stored energy is transformed into kinetic energy of the projectile using a catapult mechanism delivering up to 4,137 J/kg in the osmotic shooting mechanism in cnidarians and 1,269 J/kg in the muscle-powered appendage strike of the mantis shrimp Odontodactylus scyllarus. The launch accelerations range from 6.6g in the frog Rana pipiens to 5,413,000g in cnidarians, the

  4. Studies on Callus Induction and Regeneration of Medicinal Plant Chicory (Cichorium intybus L. from Leaf and Petiole Explants

    H. Hadizadeh


    Full Text Available Introduction: Chicory (Cichorium intybus L. belongs to Asteraceae family is commonly known as witloof chicory. The leaves and the roots of this medicinal plant are edible and commonly used as salad. Some varieties are also cultivated as coffee substitute after roasting the roots. All parts of the plant contain these volatile oils, with the majority of the toxic components concentrated in the plant's root. In folk medicine, the plant is used for the treatment of diarrhea, spleen enlargement, fever, and vomiting. Antihepatotoxic activity on damaged rat’s liver sections and anti-bacterial activity of this crop has been recently reported. In vitro regeneration from leaf explants with various hormonal combinations has been reported previously. Moreover, in vitro regeneration of Chicory from cotyledon explants using different combinations of plant growth regulators has been studied. Also, a protocol for the regeneration of plantlets from leaf and petiole explants of witloof chicory has been developed. The aim of the present investigation was optimization of callus induction and shoot regeneration from leaf and petiole tissues of Chicory (Esfahan genotype. Materials and Methods: In this investigation, Esfahan genotype was used for callus induction and direct shoot regeneration. Seeds were first washed with running tap water for 30 min then seeds were surface sterilized by dipping in 70% ethanol for 90 s and rinsed with sterile distilled water, followed by immersing in 5% sodium hypochlorite solution for 25 min and thereafter rinsed for 30 min with sterile distilled water. The basal medium used in this investigation was MS. For shoot regeneration, leaf and petiole explants (5 mm segments were excised from 4-week-old sterile seedlings and cultured on MS medium containing different combinations of NAA / BA and KIN / BA in two separate experiments. Experiments were performed factorial based on completely randomized design. Cultures were incubated at 25

  5. Agrobacterium-mediated transformation of Eucalyptus globulus using explants with shoot apex with introduction of bacterial choline oxidase gene to enhance salt tolerance.

    Matsunaga, Etsuko; Nanto, Kazuya; Oishi, Masatoshi; Ebinuma, Hiroyasu; Morishita, Yoshihiko; Sakurai, Nozomu; Suzuki, Hideyuki; Shibata, Daisuke; Shimada, Teruhisa


    Eucalyptus globulus is one of the most economically important plantation hardwoods for paper making. However, its low transformation frequency has prevented genetic engineering of this species with useful genes. We found the hypocotyl section with a shoot apex has the highest regeneration ability among another hypocotyl sections, and have developed an efficient Agrobacterium-mediated transformation method using these materials. We then introduced a salt tolerance gene, namely a bacterial choline oxidase gene (codA) with a GUS reporter gene, into E. globulus. The highest frequency of transgenic shoot regeneration from hypocotyls with shoot apex was 7.4% and the average frequency in four experiments was 4.0%, 12-fold higher than that from hypocotyls without shoot apex. Using about 10,000 explants, over 250 regenerated buds were confirmed as transformants by GUS analysis. Southern blot analysis of 100 elongated shoots confirmed successful generation of stable transformants. Accumulation of glycinebetaine was investigated in 44 selected transgenic lines, which showed 1- to 12-fold higher glycinebetaine levels than non-transgenic controls. Rooting of 16 transgenic lines was successful using a photoautotrophic method under enrichment with 1,000 ppm CO(2). The transgenic whole plantlets were transplanted into potting soil and grown normally in a growth room. They showed salt tolerance to 300 mM NaCl. The points of our system are using explants with shoot apex as materials, inhibiting the elongation of the apex on the selection medium, and regenerating transgenic buds from the side opposite to the apex. This approach may also solve transformation problems in other important plants.

  6. Cell proliferation is necessary for the regeneration of oral structures in the anthozoan cnidarian Nematostella vectensis

    Passamaneck Yale J


    Full Text Available Abstract Background The contribution of cell proliferation to regeneration varies greatly between different metazoan models. Planarians rely on pluripotent neoblasts and amphibian limb regeneration depends upon formation of a proliferative blastema, while regeneration in Hydra can occur in the absence of cell proliferation. Recently, the cnidarian Nematostella vectensis has shown potential as a model for studies of regeneration because of the ability to conduct comparative studies of patterning during embryonic development, asexual reproduction, and regeneration. The present study investigates the pattern of cell proliferation during the regeneration of oral structures and the role of cell proliferation in this process. Results In intact polyps, cell proliferation is observed in both ectodermal and endodermal tissues throughout the entire oral-aboral axis, including in the tentacles and physa. Following bisection, there is initially little change in proliferation at the wound site of the aboral fragment, however, beginning 18 to 24 hours after amputation there is a dramatic increase in cell proliferation at the wound site in the aboral fragment. This elevated level of proliferation is maintained throughout the course or regeneration of oral structures, including the tentacles, the mouth, and the pharynx. Treatments with the cell proliferation inhibitors hydroxyurea and nocodazole demonstrate that cell proliferation is indispensable for the regeneration of oral structures. Although inhibition of regeneration by nocodazole was generally irreversible, secondary amputation reinitiates cell proliferation and regeneration. Conclusions The study has found that high levels of cell proliferation characterize the regeneration of oral structures in Nematostella, and that this cell proliferation is necessary for the proper progression of regeneration. Thus, while cell proliferation contributes to regeneration of oral structures in both Nematostella and

  7. Proliferative verrucous leukoplakia: diagnosis, management and current advances.

    Capella, Diogo Lenzi; Gonçalves, Jussara Maria; Abrantes, Adelino António Artur; Grando, Liliane Janete; Daniel, Filipe Ivan

    Proliferative verrucous leukoplakia is a multifocal and progressive lesion of the oral mucosa, with unknown etiology, and commonly resistant to all therapy attempts with frequent recurrences. It is characterized by a high rate of oral squamous cell carcinoma and verrucou carcinoma transformations. To analyze the studies about Proliferative verrucous leukoplakia and develop a concise update. A Pubmed search identifying studies (laboratory research, case series and reviews of literature) that examined patients with Proliferative verrucous leukoplakia was realized. There are not enough studies about Proliferative verrucous leukoplakia in the literature. The few found studies not present a consensus about its etiology and diagnosis criteria. Although several treatment strategies have been proposed, most of them still show a high recurrence rate. More research about Proliferative verrucous leukoplakia is necessary to understand and treat this disease. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  8. Regeneration of periodontal tissues: guided tissue regeneration.

    Villar, Cristina C; Cochran, David L


    The concept that only fibroblasts from the periodontal ligament or undifferentiated mesenchymal cells have the potential to re-create the original periodontal attachment has been long recognized. Based on this concept, guided tissue regeneration has been applied with variable success to regenerate periodontal defects. Quantitative analysis of clinical outcomes after guided tissue regeneration suggests that this therapy is a successful and predictable procedure to treat narrow intrabony defects and class II mandibular furcations, but offers limited benefits in the treatment of other types of periodontal defects.

  9. Effect of colchicine applied to callus of mangosteen on morphological changes of regenerated plants

    Te-chato, S.


    Full Text Available Calli of mangosteen raised on callus induction medium (CIM at 20 days of culture were submerged in various concentrations of colchicine. The cultures were incubated on a rotary shaker and shaken at 80 rpm for 2 hours. In the case of high concentrations of colchicine (500 and 750 mg/l, the calli were cultured directily on the colchicine-containing media for 90 days. The results showed that leaves of regenerated shoots contained more chlorophyll b than those of control. However, shoot size, leaf area and leaf number tended to decrease while number and lenght of roots increased. A high concentration of colchicine, 500 mg/l, produced shoots with brown-callused leaves. However, roots could be induced from these shoots to from complete plantlets. Some of the intact leaves produced a large number of shoots. Colchicine at 750 mg/l gave some morphological abnormalities with 5 roots per shoot. A small shoot could produce a large healthy root. Some shoots produced 3 leaves per whorl.

  10. Contagion in Mass Killings and School Shootings.

    Towers, Sherry; Gomez-Lievano, Andres; Khan, Maryam; Mubayi, Anuj; Castillo-Chavez, Carlos


    Several past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts. Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed). We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event. We find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015). We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001). All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings.

  11. Contagion in Mass Killings and School Shootings.

    Sherry Towers

    Full Text Available Several past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts.Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed. We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event.We find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015. We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001. All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings.

  12. Contagion in Mass Killings and School Shootings

    Towers, Sherry; Gomez-Lievano, Andres; Khan, Maryam; Mubayi, Anuj; Castillo-Chavez, Carlos


    Background Several past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts. Methods Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed). We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event. Conclusions We find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015). We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001). All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings. PMID:26135941

  13. Transcriptional components of anteroposterior positional information during zebrafish fin regeneration.

    Nachtrab, Gregory; Kikuchi, Kazu; Tornini, Valerie A; Poss, Kenneth D


    Many fish and salamander species regenerate amputated fins or limbs, restoring the size and shape of the original appendage. Regeneration requires that spared cells retain or recall information encoding pattern, a phenomenon termed positional memory. Few factors have been implicated in positional memory during vertebrate appendage regeneration. Here, we investigated potential regulators of anteroposterior (AP) pattern during fin regeneration in adult zebrafish. Sequence-based profiling from tissues along the AP axis of uninjured pectoral fins identified many genes with region-specific expression, several of which encoded transcription factors with known AP-specific expression or function in developing embryonic pectoral appendages. Transgenic reporter strains revealed that regulatory sequences of the transcription factor gene alx4a activated expression in fibroblasts and osteoblasts within anterior fin rays, whereas hand2 regulatory sequences activated expression in these same cell types within posterior rays. Transgenic overexpression of hand2 in all pectoral fin rays did not affect formation of the proliferative regeneration blastema, yet modified the lengths and widths of regenerating bones. Hand2 influenced the character of regenerated rays in part by elevation of the vitamin D-inactivating enzyme encoded by cyp24a1, contributing to region-specific regulation of bone metabolism. Systemic administration of vitamin D during regeneration partially rescued bone defects resulting from hand2 overexpression. Thus, bone-forming cells in a regenerating appendage maintain expression throughout life of transcription factor genes that can influence AP pattern, and differ across the AP axis in their expression signatures of these and other genes. These findings have implications for mechanisms of positional memory in vertebrate tissues.

  14. Extracellular matrix components in peripheral nerve regeneration.

    Gonzalez-Perez, Francisco; Udina, Esther; Navarro, Xavier


    Injured axons of the peripheral nerve are able to regenerate and, eventually, reinnervate target organs. However, functional recovery is usually poor after severe nerve injuries. The switch of Schwann cells to a proliferative state, secretion of trophic factors, and the presence of extracellular matrix (ECM) molecules (such as collagen, laminin, or fibronectin) in the distal stump are key elements to create a permissive environment for axons to grow. In this review, we focus attention on the ECM components and their tropic role in axonal regeneration. These components can also be used as molecular cues to guide the axons through artificial nerve guides in attempts to better mimic the natural environment found in a degenerating nerve. Most used scaffolds tested are based on natural molecules that form the ECM, but use of synthetic polymers and functionalization of hydrogels are bringing new options. Progress in tissue engineering will eventually lead to the design of composite artificial nerve grafts that may replace the use of autologous nerve grafts to sustain regeneration over long gaps.


    Özge Çelik


    Full Text Available In this study, the aim was to determine the effect of magnetic fields on regeneration of Paulownia node cultures. Paulownia tomentosa node cultures were used to generate explants and these explants were passed through a 2.9- 4.6-mT magnetic flux density 1 and 9 times at 2.2 and 19.8 seconds, respectively. Chlorophyll quantities, total RNA concentrations of shoots and shoot formation rates from control and treated explants were determined. While the shoot formation rate was 61.9% in the control group, this rate was increased in magnetic field experiments and shoot formation was 82.5% in the explants that were exposed to a magnetic field for a 2.2 second period. However, the regeneration percentage of the explants exposed to a MF for a period of 19.8 s was 45%. Chlorophyll a, chlorophyll b and total chlorophyll contents of the 2.2 s group were increased in comparison to the control group. Total RNA concentrations of seedlings regenerated from treatment explants treated for 2.2 seconds significantly increased in comparison to the control (p<0.05. Our experiments show that the exposure duration to MFs is an important factor for plant tissue. MFs may be used in in vitro regeneration studies rapid and for a short time.

  16. An Efficient In Vitro Regeneration System for Ornamental Ginger (Hedychium spp.)

    An improved and efficient regeneration protocol was established for Hedychium via somatic embryogenesis. The plant material used consisted of 11 species and 9 cultivars of Hedychium. The explants consisted of young leaves taken from lateral or terminal shoots of mature greenhouse grown plants. These...

  17. Efficient soybean regeneration and Agrobacterium-mediated transformation using a whole cotyledonary node as an explant.

    Zhang, Fuli; Chen, Can; Ge, Honglian; Liu, Jinmei; Luo, Yunling; Liu, Kun; Chen, Long; Xu, Kedong; Zhang, Yi; Tan, Guangxuan; Li, Chengwei


    An optimized regeneration and Agrobacterium-mediated transformation protocol based on whole cotyledonary node explants was developed in soybean (Glycine max) cultivar Zhong Huang 13. Adding 6-benzylaminopurine (BAP) in a germinating medium could significantly increase regeneration efficiency; the optimal BAP concentration for shoot formation was 0.5 mg/L. The concentrations of plant growth regulators in a shoot induction medium were optimized by the orthogonal test [L9 (3(3))]. The best combination for shoot regeneration was a medium of Murashige & Skoog salts with B5 vitamins (MSB) supplemented with 3.5 mg/L BAP, 0.2 mg/L indole-3-butyric acid (IBA), and 0.2 mg/L kinetin (KT). Under this favorable condition, one node could regenerate 28-30 shoots. Soybean whole cotyledonary nodes were transformed by inoculation with A. tumefaciens strain EHA105 harboring a vector pBI121 containing a β-glucuronidase gene (gus). GUS assay, polymerase chain reaction, and Southern blot analysis indicated that the gus gene was transformed into soybean plants with 23.1% transformation efficiency. Transgenic plants could be obtained within 5-6 weeks, which was about 4 weeks less than that of a traditional single cotyledonary node method.

  18. Notch Signaling Inhibits Axon Regeneration

    Bejjani, Rachid El; Hammarlund, Marc


    Many neurons have limited capacity to regenerate their axons after injury. Neurons in the mammalian CNS do not regenerate, and even neurons in the PNS often fail to regenerate to their former targets. This failure is likely due in part to pathways that actively restrict regeneration; however, only a few factors that limit regeneration are known. Here, using single-neuron analysis of regeneration in vivo, we show that Notch/lin-12 signaling inhibits the regeneration of mature C. elegans neuron...

  19. Differentiated skeletal cells contribute to blastema formation during zebrafish fin regeneration.

    Sousa, Sara; Afonso, Nuno; Bensimon-Brito, Anabela; Fonseca, Mariana; Simões, Mariana; Leon, Joaquín; Roehl, Henry; Cancela, Maria Leonor; Jacinto, António


    The origin of cells that generate the blastema following appendage amputation has been a long-standing question in epimorphic regeneration studies. The blastema is thought to originate from either stem (or progenitor) cells or differentiated cells of various tissues that undergo dedifferentiation. Here, we investigate the origin of cells that contribute to the regeneration of zebrafish caudal fin skeletal elements. We provide evidence that the process of lepidotrichia (bony rays) regeneration is initiated as early as 24 hours post-amputation and that differentiated scleroblasts acquire a proliferative state, detach from the lepidotrichia surface, migrate distally, integrate into the blastema and dedifferentiate. These findings provide novel insights into the origin of cells in epimorphic appendage regeneration in zebrafish and suggest conservation of regeneration mechanisms between fish and amphibians.

  20. Analysis on Pathogenesis of 50 Cases of Bladder Proliferative Lesions

    陈志强; 蓝儒竹; 叶章群; 杨为民


    In order to study the pathogenesis, clinical and pathological characteristics of prolifera-tive lesions of the bladder, 50 cases of proliferative lesions of the bladder from 150 patients withcomplaints of frequency, urgency, hematuria and dysuria were subjected to cystoscopic biopsy ofthe suspicious foci in the bladder. In combination with the symptoms, urine routine and urodynam-ics, the relationship of proliferative lesions of the bladder to the inflammation and obstruction of thelower urinary tract was analyzed. Of the 50 cases of proliferative bladder lesions, 44 cases (88%)had lower urinary tract infection and 29 (58%) lower urinary tract obstruction. The patients withlower urinary tract obstruction were all complicated with infection. Three cases were associatedwith transitional cell carcinoma. Malignant cells were detected in 1 case by urinary cytologic exami-nation. Proliferative lesions of the bladder, especially those without other obvious mucosa changesunder cystoscopy, are common histological variants of urothelium in the patients with chronic in-flammation and obstruction of the lower urinary tract. Chronic inflammation and obstruction of thelower urinary tract might be the causes for proliferative lesions of the bladder. It is suggested thatdifferent treatments should be applied according to the scope and histological type of the prolifera-tive lesions.

  1. Proliferative and inflammatory factors in the vitreous of patients with proliferative diabetic retinopathy

    V V Chernykh


    Full Text Available Purpose: The purpose was to measure the concentrations of various cytokines and growth factors (including vascular endothelial growth factor [VEGF] and pigment epithelium-derived factor [PEDF] in the vitreous of patients with proliferative diabetic retinopathy (PDR and to investigate interaction between inflammatory and proliferative factors in the genesis of PDR. Materials and Methods : Vitreous samples from 32 eyes with PDR and 25 eyes without diabetes mellitus and signs of DR (control were collected. Vitreous concentrations of VEGF, PEDF, monocyte chemotactic protein-1 (MCP-1, interleukin-4 (IL-4, IL-6, IL-8, IL-10, IL-17A, and secretory immunoglobulin A (sIgA were simultaneously measured using enzyme-linked immunoassay. Results : Vitreous levels of VEGF, PEDF, IL-17A, IL-6, IL-8, IL-4, and sIgA were significantly (Π < 0.05 higher in eyes with PDR compared to control. The concentration of VEGF was more than 17-times higher than in control, and the concentration of PEDF was not changed oppositely and was also higher (1.45-times compared to control, that may indicate disturbances of compensatory mechanisms in angiogenesis regulation in PDR. Significant (Π < 0.05 positive correlations were observed between vitreous concentrations of VEGF and IL-17ΐ (r = 0.45, VEGF and IL-8 (r = 0.48, VEGF and IL-4 (r = 0.51, PEDF and IL-17ΐ (r = 0.48, PEDF and IL-8 (r = 0.59, MCP-1 and PEDF (r = 0.72, MCP-1 and IL-8 (r0 = 0.45, IL-4 and IL-17ΐ (r = 0.65, IL-4 and IL-8 (r = 0.71, IL-8 and IL-17ΐ (r = 0.59. Conclusions: Significantly raised levels of inflammatory and proliferative factors and numerous positive correlations between them may demonstrate a significant role of activation of vascular proliferation and local inflammation in the pathogenesis of PDR.

  2. Micropropagation of a Thai medicinal plant for women's health, Curcuma comosa Roxb., via shoot and microrhizome inductions.

    Lo-apirukkul, Sureerat; Jenjittikul, Thaya; Saralamp, Promchit; Prathanturarug, Sompop


    We studied the effects of explant types, plant growth regulators, and sucrose concentrations on shoot and microrhizome inductions of Curcuma comosa Roxb., an important Thai medicinal plant for women's health. Explant types significantly affected shoot induction of the plant. The maximum shoot multiplication rate of 11.82 ± 1.03 shoots/responding explant was obtained when culturing terminal bud explants on semi-solid Murashige and Skoog (MS) medium supplemented with 18.16 μM thidiazuron for 8 weeks. Subsequently, they were transferred to a semi-solid MS medium without plant growth regulators for 4 weeks. The regenerated shoots produced roots spontaneously. Rooted plantlets were successfully transferred to the soil. Microrhizome induction was significantly influenced by sucrose concentrations, but not by 6-benzyladenine (BA). Liquid MS medium with a combination of 17.76 μM BA and 50 g L(-1) sucrose was optimal for microrhizome induction of C. comosa. After 12 weeks of culture, the microrhizome induction rate was 3.36 ± 0.44 microrhizomes/responding explant. Starch accumulation in microrhizomes increased with higher sugar concentration and with longer duration of culture. The microrhizomes were allowed to germinate under greenhouse conditions and further developed into normal plants. The protocols established will be used for the production of uniform plantlets suitable for field plantation for the herbal industry.

  3. Optimization of in vitro regeneration and Agrobacterium tumefaciens-mediated transformation with heat-resistant cDNA in Brassica oleracea subsp. italica cv. Green Marvel.

    Ravanfar, Seyed Ali; Aziz, Maheran Abdul; Saud, Halimi Mohd; Abdullah, Janna Ong


    An efficient system for shoot regeneration and Agrobacterium tumefaciens-mediated transformation of Brassica oleracea cv. Green Marvel cultivar is described. This study focuses on developing shoot regeneration from hypocotyl explants of broccoli cv. Green Marvel using thidiazuron (TDZ), zeatin, and kinetin, the optimization of factors affecting Agrobacterium-mediated transformation of the hypocotyl explants with heat-resistant cDNA, followed by the confirmation of transgenicity of the regenerants. High shoot regeneration was observed in 0.05-0.1 mg dm(-3) TDZ. TDZ at 0.1 mg dm(-3) produced among the highest percentage of shoot regeneration (96.67 %) and mean number of shoot formation (6.17). The highest percentage (13.33 %) and mean number (0.17) of putative transformant production were on hypocotyl explants subjected to preculture on shoot regeneration medium (SRM) with 200 µM acetosyringone. On optimization of bacterial density and inoculation time, the highest percentage and mean number of putative transformant production were on hypocotyl explants inoculated with a bacterial dilution of 1:5 for 30 min. Polymerase chain reaction (PCR) assay indicated a transformation efficiency of 8.33 %. The luciferase assay showed stable integration of the Arabidopsis thaliana HSP101 (AtHSP101) cDNA in the transgenic broccoli regenerants. Three out of five transgenic lines confirmed through PCR showed positive hybridization bands of the AtHSP101 cDNA through Southern blot analysis. The presence of AtHSP101 transcripts in the three transgenic broccoli lines indicated by reverse transcription-PCR (RT-PCR) confirmed the expression of the gene. In conclusion, an improved regeneration system has been established from hypocotyl explants of broccoli followed by successful transformation with AtHSP101 for resistance to high temperature.

  4. Microdissection of shoot meristem functional domains.

    Lionel Brooks


    Full Text Available The shoot apical meristem (SAM maintains a pool of indeterminate cells within the SAM proper, while lateral organs are initiated from the SAM periphery. Laser microdissection-microarray technology was used to compare transcriptional profiles within these SAM domains to identify novel maize genes that function during leaf development. Nine hundred and sixty-two differentially expressed maize genes were detected; control genes known to be upregulated in the initiating leaf (P0/P1 or in the SAM proper verified the precision of the microdissections. Genes involved in cell division/growth, cell wall biosynthesis, chromatin remodeling, RNA binding, and translation are especially upregulated in initiating leaves, whereas genes functioning during protein fate and DNA repair are more abundant in the SAM proper. In situ hybridization analyses confirmed the expression patterns of six previously uncharacterized maize genes upregulated in the P0/P1. P0/P1-upregulated genes that were also shown to be downregulated in leaf-arrested shoots treated with an auxin transport inhibitor are especially implicated to function during early events in maize leaf initiation. Reverse genetic analyses of asceapen1 (asc1, a maize D4-cyclin gene upregulated in the P0/P1, revealed novel leaf phenotypes, less genetic redundancy, and expanded D4-CYCLIN function during maize shoot development as compared to Arabidopsis. These analyses generated a unique SAM domain-specific database that provides new insight into SAM function and a useful platform for reverse genetic analyses of shoot development in maize.

  5. Shooting Gallery Notes. Working Paper #22. Preliminary.

    Bourgois, Philippe

    This paper contains ethnographic participant-observation field notes taken on a one-night visit to a "shooting gallery" in East Harlem (New York City) along with background information and commentary. East Harlem, also referred to as "El Barrio" or Spanish Harlem, is a 200-square block neighborhood on the upper East Side of Manhattan in New York…

  6. Physiological Disorders of Pear Shoot Cultures

    Physiological disorders are some of the most difficult challenges in micropropagation. Little is known of the causes of plant growth disorders which include callus formation, hyperhydricity, shoot tip necrosis, leaf lesions, epinasty, fasciation and hypertrophy. During our study of mineral nutritio...

  7. Hangzhou People and Bamboo Shoots Dish



    SOON we’ll celebrate the new year. According to Hangzhou tradition, every family will cook a hot dish for this feast which will include shredded winter bamboo shoots, hotbed chives, shredded meat and smoked bean curd. In addition, some families will also cook a dish of "braised

  8. School Shootings; Standards Kill Students and Society

    Angert, Betsy L.


    School shootings have been in the news of late. People ponder what occurs in classrooms today. Why would a young person wish to take a life? Within educational institutions, the killings are a concern. In our dire attempt to teach the children and ensure student success, it seems many of our offspring are lost. Some students feel separate from…

  9. Enhancing plant regeneration in tissue culture: a molecular approach through manipulation of cytokinin sensitivity.

    Hill, Kristine; Schaller, G Eric


    Micropropagation is used for commercial purposes worldwide, but the capacity to undergo somatic organogenesis and plant regeneration varies greatly among species. The plant hormones auxin and cytokinin are critical for plant regeneration in tissue culture, with cytokinin playing an instrumental role in shoot organogenesis. Type-B response regulators govern the transcriptional output in response to cytokinin and are required for plant regeneration. In our paper published in Plant Physiology, we explored the functional redundancy among the 11 type-B Arabidopsis response regulators (ARRs). Interestingly, we discovered that the enhanced expression of one family member, ARR10, induced hypersensitivity to cytokinin in multiple assays, including callus greening and shoot induction of explants. Here we 1) discuss the hormone dependence for in vitro plant regeneration, 2) how manipulation of the cytokinin response has been used to enhance plant regeneration, and 3) the potential of the ARR10 transgene as a tool to increase the regeneration capacity of agriculturally important crop plants. The efficacy of ARR10 for enhancing plant regeneration likely arises from its ability to transcriptionally regulate key cytokinin responsive genes combined with an enhanced protein stability of ARR10 compared with other type-B ARRs. By increasing the capacity of key tissues and cell types to respond to cytokinin, ARR10, or other type-B response regulators with similar properties, could be used as a tool to combat the recalcitrance of some crop species to tissue culture techniques.

  10. Stirling convertor regenerators

    Ibrahim, Mounir B


    Stirling Convertor Regenerators addresses the latest developments and future possibilities in the science and practical application of Stirling engine regenerators and technology. Written by experts in the vanguard of alternative energy, this invaluable resource presents integral scientific details and design concepts associated with Stirling converter regenerators. Content is reinforced with novel insights and remarkable firsthand experience that the authors and their colleagues acquired while working at the National Aeronautics and Space Administration (NASA) and other leading organizations.

  11. In vitro plant regeneration of Albizia lebbeck (L. from seed explants

    S. Perveen


    Full Text Available Objectives: An efficient and reproducible regeneration protocol for rapid multiplication of Albizia lebbeck (L. was developed by using intact seed explants.Methods: Murashige and Skoog's (MS medium supplemented with different hormones (BA, Kn, GA3 and TDZ was used for the induction of multiple shoots from the seed explants. Ex-vitro rooting was performed by using pulse treatment method in auxins (IBA and NAA and the complete plantlets were transferred to the field.Results: High frequency direct shoot induction was found in aseptic seed cultures of A. lebbeck on Murashige and Skoog medium supplemented with 5.0 µM TDZ (Thiadiazuron. Seeds were germinated after 7 days of culture and induced maximum 8 shoots from the region adjacent to the apex of the primary shoot of the seedling upto 25 days of incubation. Proliferating shoot cultures with increased shoot length was established by sub-culture of excised sprouting epicotyls on MS medium supplied with reduced concentrations of TDZ. Maximum shoot regeneration frequency (76 % with  highest number of shoots (21 and shoot length (5.1 cm per sprouting epicotyl was observed in the MS medium supplemented with 0.5 µM TDZ after 8 weeks of culture. Different concentrations of Indole-3-butyric acid (IBA and α-naphthalene acetic acid (NAA were tested to determine the optimal conditions for ex-vitro rooting of the microshoots. The best treatment for maximum ex-vitro root induction frequency (81 % was accomplished with IBA (250 µM pulse treatment given to the basal end of the microshoots for 30 min followed by their transfer in plastic cups containing soilrite and eventually established in normal garden soil + soilrite (1:1 with 78 % survival rate. In addition, histological study was undertaken to gain a better understanding of the regenerated shoots from the epicotyl region.Conclusion: The findings will be fruitful in getting a time saving and cost effective protocol for the in vitro propagation of Albizia

  12. In vitro plant regeneration from leaves and internode sections of sweet cherry cultivars (Prunus avium L.).

    Matt, Andrea; Jehle, Johannes A


    Regeneration of adventitious shoots from leaves and, for the first time, from internode sections were compared and optimized for five economically important sweet cherry cultivars, i.e. "Schneiders", "Sweetheart", "Starking Hardy Giant", "Kordia" and "Regina" (Prunus avium L.). The influence of basal media, carbon source, combination and dosage of phytohormones, ethylene inhibitor such as silver thiosulfate and a 16 h:8 h light:dark photoperiod versus complete darkness were evaluated. Both, DKW/WPM (1:1) and Quoirin/Lepoivre (QL) basal media stimulated organogenesis more than QL/WPM (1:1), Chee and Pool (CP), Murashige Skoog (MS), Driver and Kuniyuki (DKW) or woody plant (WPM) media did. An induction phase in darkness resulted in lower or zero regeneration rates. The best regeneration efficiencies were generally obtained with thidiazuron in combination with indole-3-butyric-acid. The addition of silver thiosulfate resulted in a similar or reduced regeneration efficiency. Significant genotypic variability in adventitious bud formation was evident for both explant sources, leaf and internode section. Adventitious shoots were obtained from 11% of leaf explants and 50% of internode sections indicating that shoot regeneration from internodes was significantly more efficient than from leaves.

  13. Is proliferative colonic disease presentation changing?

    Vito D Corleto; Cristiano Pagnini; Maria Sofia Cattaruzza; Ermira Zykaj; Emilio Di Giulio; Giovanna Margagnoni; Emanuela Pilozzi


    AIM:To compare the site,age and gender of cases of colorectal cancer (CRC) and polyps in a single referral center in Rome,Italy,during two periods.METHODS:CRC data were collected from surgery/pathology registers,and polyp data from colonoscopy reports.Patients who met the criteria for familial adenomatous polyposis,hereditary non-polyposis colorectal cancer syndrome or inflammatory bowel disease were excluded from the study.Overlap of patients between the two groups (cancers and polyps) was carefully avoided.Thex2 statistical test and a regression analysis were performed.RESULTS:Data from a total of 768 patients (352 and 416 patients,respectively,in periods A and B) who underwent surgery for cancer were collected.During the same time periods,a total of 1693 polyps were analyzed from 978 patients with complete colonoscopies (428 polyps from 273 patients during period A and 1265 polyps from 705 patients during period B).A proximal shift in cancer occurred during the latter years for both sexes,but particularly in males.Proximal cancer increased > 3-fold in period B compared to period A in males [odds ratio (OR) 3.31,95%CI:2.00-5.47; P <0.0001).A similar proximal shift was observed for polyps,particularly in males (OR 1.87,95%CI:1.23-2.87;P < 0.0038),but also in females (OR 1.62,95%CI:0.96-2.73; P < 0.07).CONCLUSION:The prevalence of proximal proliferative colonic lesions seems to have increased over the last decade,particularly in males.

  14. Intravitreal methotrexate infusion for proliferative vitreoretinopathy

    Sadaka A


    Full Text Available Ama Sadaka,1 Robert A Sisk,1–3 James M Osher,1,3 Okan Toygar,4 Melinda K Duncan,5 Christopher D Riemann1,3 1Department of Ophthalmology, University of Cincinnati College of Medicine, 2Department of Opthalmology, Cincinnati Children’s Hospital Medical Center, 3Cincinnati Eye Institute, Cincinnati, OH, USA; 4Department of Ophthalmology, Bahcesehir University Medical Faculty, Istanbul, Turkey; 5Department of Biological Sciences, University of Delaware, Newark, DE, USA Purpose: The purpose of this study was to evaluate intravitreal methotrexate infusion (IMI during pars plana vitrectomy (PPV for retinal detachment in patients with high risk for the development of proliferative vitreoretinopathy (PVR.Methods: Patients presenting with severe recurrent PVR with tractional retinal detachment and/or a history of severe ocular inflammation were treated with IMI. Clinical outcomes were determined from a retrospective medical chart review.Results: Twenty-nine eyes presenting with either tractional retinal detachment and recurrent PVR (n=22 or a history of severe inflammation associated with high PVR risk (n=7 received IMI during PPV. Best-corrected visual acuity at 6 months was ≥20/200 in 19 of 29 eyes (66% and remained stable or improved compared with initial presentation in 24 of 29 eyes (83%. At the last follow-up examination, the retinas of 26 of 29 eyes (90% remained attached after IMI while three eyes required another reattachment procedure. Three additional eyes (10% developed recurrent limited PVR without recurrent RD and were observed. No complications attributable to IMI occurred during a mean follow-up of 27 months.Conclusion: Eyes at high risk for PVR development due to a history of prior PVR or intraocular inflammation had a low incidence of PVR following IMI at the time of PPV for RD repair. No significant safety issues from IMI were observed in this series. Keywords: tractional retinal detachment, recurrent retinal detachment, pars

  15. Comparative Study on Antioxidative System in Normal and Vitrified Shoots of Populus suaveolens in Tissue Culture

    Lin Shanzhi; Zhang Zhiyi; Lin Yuanzhen; Liu Wenfeng; Guo Huan; Zhang Wei; Zhang Chong


    To explore the physiological and biochemical mechanism of the occurrence of vitrified shoots of Populus suaveolens in tissue culture, the changes in water, chlorphyll, lignin, H2O2, phenylalanine ammonialyase (PAL), malonaldehyde (MDA), protective enzymatic systems, and some key enzymes involved in the ascorbate- glutathione cycle were comparatively studied in both normal and vitrified shoots of P. Suaveolens. The results show that the lower activities of peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR) and PAL, and the less contents of chlorphyll, lignin, ascorbate (ASA) and reduced glutathione (GSH) as well as the lower ratios of ASA / DHA and GSH / GSSG are observed in vitrified shoots than in normal ones during the whole culture period. While in comparison with normal shoots, the higher activity of superoxide dismutase (SOD) and the more concentrations of water, H2O2, MDA, dehydroascorbate (DHA) and oxidized glutathione (GSSG) are found in vitrified shoots. Statistical analysis indicates that the enhanced activity of SOD and the decreased activities of CAT and POD as well as some enzymes involved in the ascorbate-glutathione cycle might be closely correlated to the accumulation of H2O2. The less regeneration of ASA and GSH and the lower capacity of the ascorbate-glutathione cycle observed in vitrified shoots might be due to a significant decrease in APX, MDAR, DHAR and GR activities and a decline in redox status of ASA and GSH. The decreases in chlorphyll content might result in a decline in photosynthesis. The lower activities of POD and PAL could result in the decrease of lignin synthesis and cell wall ligination, which might be the key factor leading to the increase in water content. It is concluded that the deficiency of detoxification capacity caused by the lower capacity of the ascorbate-glutathione pathway and the decreased activity of protective enzymatic system might lead to the

  16. Visual selection and maintenance of the cell lines with high plant regeneration ability and low ploidy level in Dianthus acicularis by monitoring with flow cytometry analysis.

    Shiba, Tomonori; Mii, Masahiro


    Efficient plant regeneration system from cell suspension cultures was established in D. acicularis (2n=90) by monitoring ploidy level and visual selection of the cultures. The ploidy level of the cell cultures closely related to the shoot regeneration ability. The cell lines comprising original ploidy levels (2C+4C cells corresponding to DNA contents of G1 and G2 cells of diploid plant, respectively) showed high regeneration ability, whereas those containing the cells with 8C or higher DNA C-values showed low or no regeneration ability. The highly regenerable cell lines thus selected consisted of compact cell clumps with yellowish color and relatively moderate growth, suggesting that it is possible to select visually the highly regenerable cell lines with the original ploidy level. All the regenerated plantlets from the highly regenerable cell cultures exhibited normal phenotypes and no variations in ploidy level were observed by flow cytometry (FCM) analysis.

  17. Plant regeneration from stem and petal of carnation (Dianthus caryophyllus L.).

    Nugent, G; Wardley-Richardson, T; Lu, C Y


    Plants were regenerated via adventitious shoot initiation from petal explants of carnation (Dianthus caryophyllus L.) cultivars Crowley Sim, Ember Rose, Orchid Beauty, Red Sim, White Sim and from stem segments of Crowley Sim, Red Sim, White Sim. Differences in cultivar response were observed, with White Sim being the most responsive for both explant types. Plants were also regenerated from receptacles of this cultivar. The effect of different cytokinins on regeneration from petal and stem explants of cultivar White Sim was compared. Thidiazuron was more effective than 6-benzylaminopurine or kinetin. In stem explants, morphogenic capacity was determined by the developmental stage of the explant. Highest percentage of shoot formation was observed in the youngest stem segments, on all the cytokinins tested. Stem-derived plants grew faster than petal or receptacle-derived plants and produced normal, flowering plants eight to ten months after culture.

  18. Ready, aim, shoot: stem cell regulation of the shoot apical meristem.

    Soyars, Cara L; James, Sean R; Nimchuk, Zachary L


    Plant shoot meristems contain stem cells that are continuously renewed to replenish cells that exit and differentiate during lateral organ formation. Complex cell-to-cell signaling systems balance division and differentiation. These center on ligand-receptor networks, hormone pathways, and transcriptional regulators that function in an integrated manner. In this review, we aim to highlight new findings in shoot stem cell regulation across species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Poised Regeneration of Zebrafish Melanocytes Involves Direct Differentiation and Concurrent Replenishment of Tissue-Resident Progenitor Cells.

    Iyengar, Sharanya; Kasheta, Melissa; Ceol, Craig J


    Efficient regeneration following injury is critical for maintaining tissue function and enabling organismal survival. Cells reconstituting damaged tissue are often generated from resident stem or progenitor cells or from cells that have dedifferentiated and become proliferative. While lineage-tracing studies have defined cellular sources of regeneration in many tissues, the process by which these cells execute the regenerative process is largely obscure. Here, we have identified tissue-resident progenitor cells that mediate regeneration of zebrafish stripe melanocytes and defined how these cells reconstitute pigmentation. Nearly all regeneration melanocytes arise through direct differentiation of progenitor cells. Wnt signaling is activated prior to differentiation, and inhibition of Wnt signaling impairs regeneration. Additional progenitors divide symmetrically to sustain the pool of progenitor cells. Combining direct differentiation with symmetric progenitor divisions may serve as a means to rapidly repair injured tissue while preserving the capacity to regenerate.

  20. Proliferative periostitis of Garré: Report of a case.

    Jacobson, H L Jay; Baumgartner, J Craig; Marshall, J Gordon; Beeler, William J


    Proliferative periostitis of Garré is described as a productive and proliferative inflammatory response of periosteum to infection or other irritation. This can be odontogenic or non-odontogenic in nature. This is a case report of an odontogenic periostitis resulting from periapical inflammation of endodontic origin. It was successfully treated by nonsurgical endodontics. Antibiotic therapy was not used during the treatment of this patient.

  1. [Proliferative vitreoretinopathy: modern view on etiology and pathogenesis].

    Artem'eva, O V; Samoĭlov, A N; Zhernakov, S V


    Studies on etiology and pathogenesis of proliferative vitreoretinopathy are necessitated by the absence of a unified theory, which would provide a clear understanding of causes and mechanisms of the disease. The results of recent investigations allow to consider proliferative vitreoretinopathy as an uncontrollable plastic process caused by certain changes in the retina aimed at survival of its cells under oxidative stress. This approach enables preclinical indication of the process and development of new therapies.

  2. Analysis of miRNAs and their targets during adventitious shoot organogenesis of Acacia crassicarpa.

    Weina Liu

    Full Text Available Organogenesis is an important process for plant regeneration by tissue or cell mass differentiation to regenerate a complete plant. MicroRNAs (miRNAs play an essential role in regulating plant development by mediating target genes at transcriptional and post-transcriptional levels, but the diversity of miRNAs and their potential roles in organogenesis of Acacia crassicarpa have rarely been investigated. In this study, approximately 10 million sequence reads were obtained from a small RNA library, from which 189 conserved miRNAs from 57 miRNA families, and 7 novel miRNAs from 5 families, were identified from A. crassicarpa organogenetic tissues. Target prediction for these miRNAs yielded 237 potentially unique genes, of which 207 received target Gene Ontology annotations. On the basis of a bioinformatic analysis, one novel and 13 conserved miRNAs were selected to investigate their possible roles in A. crassicarpa organogenesis by qRT-PCR. The stage-specific expression patterns of the miRNAs provided information on their possible regulatory functions, including shoot bud formation, modulated function after transfer of the culture to light, and regulatory roles during induction of organogenesis. This study is the first to investigate miRNAs associated with A. crassicarpa organogenesis. The results provide a foundation for further characterization of miRNA expression profiles and roles in the regulation of diverse physiological pathways during adventitious shoot organogenesis of A. crassicarpa.

  3. Sound propagation from a semi-open shooting range

    Eerden, F.J.M. van der; Berg, F. van den


    Semi-open shooting ranges, in contrast to a fully open shooting range, are often used in the densely populated area of the Netherlands. The Ministry of Defense operates a number of these ranges. In these shooting ranges above the line of fire a number of screens are situated for safety precautions t

  4. Benign Proliferative Breast Lesions and Risk of Cancer

    Serap Erel


    Full Text Available Benign breast lesions (BBL includes a wide variety of histologic entities, which have been broadly classified into non-proliferative lesions, proliferative lesions without atypia, and hyperplasia with atypia. With the increased use of mammography, more benign lesions are being detected, and in order to estimate the risk of breast cancer for specific histologic categories is of great importance to guide clinical management. Women with proliferative lesions without atypia are at slightly increased risk of subsequent breast cancer, whereas women with proliferative lesions with atypia have a higher risk. The risk is 1.5- 2-fold in women with proliferative lesions without atypia, 4-5-fold in women with proliferative lesions with atypia, and 8-10 fold in women with ductal carcinoma in situ. Age at diagnosis of BBL, menopausal status, family history of breast cancer in a first-degree relative, and time since BBL diagnosis on risk of breast cancer are important for risk evaluation. [Archives Medical Review Journal 2010; 19(3.000: 155-167

  5. Transport of Nutrients Determines Growth in Tissue Culture; Why apple shoots grow rapidly and tulip shoots grow slowly

    Klerk, de G.J.M.


    Tulip growth in vitro is seriously impaired by inferior transport in the shoots. As a result, tulip cannot be micropropagated commercially using conventional means. In contrast, apple shoots show high transport and are easily micropropagated.

  6. Pirfenidone inhibits post-traumatic proliferative vitreoretinopathy.

    Khanum, B N M K; Guha, R; Sur, V P; Nandi, S; Basak, S K; Konar, A; Hazra, S


    PurposeThe purpose of the study was to evaluate the efficacy and safety of intravitreal pirfenidone for inhibition of proliferative vitreoretinopathy (PVR) in a model of penetrating ocular injury.Patients and methodsPenetrating trauma was induced on the retina of rabbit and treated either with 0.1 ml of phosphate-buffered saline (PBS) or 0.1 ml of 0.5% pirfenidone, and development of PVR was evaluated clinically and graded after 1 month. Histopathology and immunohistochemistry with transforming growth factor beta (TGFβ), alpha smooth muscle actin (αSMA), and collagen-1 were performed to assess the fibrotic changes. Expression of cytokines in the vitro-retinal tissues at different time points following pirfenidone and PBS injection was examined by RT-PCR. Availability of pirfenidone in the vitreous of rabbit at various time points was determined by high-performance liquid chromatography following injection of 0.1 ml of 0.5% pirfenidone. In normal rabbit eye, 0.1 ml of 0.5% pirfenidone was injected to evaluate any toxic effect.ResultsClinical assessment and grading revealed prevention of PVR formation in pirfenidone-treated animals, gross histology, and histopathology confirmed the observation. Immunohistochemistry showed prevention in the expression of collagen-I, αSMA, and TGFβ in the pirfenidone-treated eyes compared to the PBS-treated eyes. Pirfenidone inhibited increased gene expression of cytokines observed in control eyes. Pirfenidone could be detected up to 48 h in the vitreous of rabbit eye following single intravitreal injection. Pirfenidone did not show any adverse effect following intravitreal injection; eyes were devoid of any abnormal clinical sign, intraocular pressure, and electroretinography did not show any significant change and histology of retina remained unchanged.ConclusionThis animal study shows that pirfenidone might be a potential therapy for PVR. Further clinical study will be useful to evaluate the clinical application of

  7. Protoplast-to-plant regeneration of American elm (Ulmus americana).

    Jones, A M P; Shukla, M R; Biswas, G C G; Saxena, P K


    This study describes a protocol for regeneration of plants from cell suspension-derived protoplasts of American elm (Ulmus americana). Efficient protoplast isolation was achieved from a two-phase culture system through the incorporation of 100 μM 2-aminoindan-2-phosphonic acid, with a yield of approximately 2 × 10(6) protoplasts/ml packed cell volume. Isolated protoplasts failed to survive in liquid or alginate bead culture systems but initiated and continued to divide when embedded in low melting point agarose beads. Protoplast-derived callus proliferated and differentiated into shoot buds in response to 10 or 20 μM thidiazuron. Differentiated buds elongated and continued to proliferate on elm shoot medium supplemented with 3.0 μM GA3. The protoplast-derived shoots rooted and acclimatized to greenhouse conditions and continued to grow. This system provides the first protoplast-to-plant regeneration system for American elm and provides a framework for the development of protoplast fusion or genome editing technologies.

  8. The Analysis of Activated Carbon Regeneration Technologies



    A series of methods for activated carbon regeneration were briefly introduced.Such as thermal regeneration,chemical regeneration,biochemical regeneration,and newly supercritical fluid regeneration, electrochemical regeneration,light-catalyzed regeneration,and microwave radiation method,and the developing trend of activated carbon regeneration was predicted.

  9. Multiple Shooting and Time Domain Decomposition Methods

    Geiger, Michael; Körkel, Stefan; Rannacher, Rolf


    This book offers a comprehensive collection of the most advanced numerical techniques for the efficient and effective solution of simulation and optimization problems governed by systems of time-dependent differential equations. The contributions present various approaches to time domain decomposition, focusing on multiple shooting and parareal algorithms.  The range of topics covers theoretical analysis of the methods, as well as their algorithmic formulation and guidelines for practical implementation. Selected examples show that the discussed approaches are mandatory for the solution of challenging practical problems. The practicability and efficiency of the presented methods is illustrated by several case studies from fluid dynamics, data compression, image processing and computational biology, giving rise to possible new research topics.  This volume, resulting from the workshop Multiple Shooting and Time Domain Decomposition Methods, held in Heidelberg in May 2013, will be of great interest to applied...

  10. Auxin at the shoot apical meristem

    Vernoux, Teva; Besnard, Fabrice; Traas, Jan


    Plants continuously generate new tissues and organs through the activity of populations of undifferentiated stem cells, called meristems. Here, we discuss the so-called shoot apical meristem (SAM), which generates all the aerial parts of the plant. It has been known for many years that auxin plays a central role in the functioning of this meristem. Auxin is not homogeneously distributed at the SAM and it is thought that this distribution is interpreted in terms of differential gene expression...

  11. Microdissection of Shoot Meristem Functional Domains

    Lionel Brooks; Josh Strable; Xiaolan Zhang; Kazuhiro Ohtsu; Ruilian Zhou; Ananda Sarkar; Sarah Hargreaves; Robert J Elshire; Douglas Eudy; Teresa Pawlowska; Doreen Ware; Diane Janick-Buckner; Brent Buckner; Timmermans, Marja C.P.; Patrick S. Schnable


    The shoot apical meristem (SAM) maintains a pool of indeterminate cells within the SAM proper, while lateral organs are initiated from the SAM periphery. Laser microdissection-microarray technology was used to compare transcriptional profiles within these SAM domains to identify novel maize genes that function during leaf development. Nine hundred and sixty-two differentially expressed maize genes were detected; control genes known to be upregulated in the initiating leaf (P0/P1) or in the SA...

  12. Recurrent posterior shoulder instability after rifle shooting.

    Cho, Jae-Ho; Chung, Nam-Su; Song, Hyung-Keun; Lee, Doo-Hyung


    Rifle shooting produces a sudden counterforce against the body thorough the anterior shoulder, which may produce a traumatic injury in soldiers. Posterior instability of the shoulder can occur in soldiers who practice rifle shooting. To the authors' knowledge, few reports have examined shooting-related injuries in soldiers. This article describes the case of a 27-year-old male soldier who presented with left shoulder pain and instability after rifle training. He developed symptoms, and presented radiographic findings consistent with a posterior Bankart lesion. Intraoperatively, while in the lateral decubitus position, a posterior portal was created 3 cm inferior and 2 cm lateral to the posterolateral corner of acromion for making a proper angle for inserting anchors. A reverse bony Bankart lesion and adjacent cartilage breakdown at the glenoid rim were noted. An arthroscopic capsulolabral repair was performed with 3-mm bioabsorbable anchors to the glenoid rim. No gross reverse Hill-Sachs lesion or hyaline cartilage lesion was noted. Postoperatively, the arm was supported in a sling with an abduction pillow for 5 weeks. Codman's exercises, scapular protraction exercises, and elbow and wrist exercises were started. Physical therapy focused on reestablishing glenohumeral range of motion and rotator cuff and periscapular muscle strength. Six months postoperatively, the patient had normal scapular kinesis and reported no shoulder pain or symptoms of instability associated with a reverse bony Bankart lesion. Copyright 2012, SLACK Incorporated.

  13. Cell-specific transcriptomic analyses of three-dimensional shoot development in the moss Physcomitrella patens.

    Frank, Margaret H; Scanlon, Michael J


    Haploid moss gametophytes harbor distinct stem cell types, including tip cells that divide in single planes to generate filamentous protonemata, and bud cells that divide in three planes to yield axial gametophore shoots. This transition from filamentous to triplanar growth occurs progressively during the moss life cycle, and is thought to mirror evolution of the first terrestrial plants from Charophycean green algal ancestors. The innovation of morphologically complex plant body plans facilitated colonization of the vertical landscape, and enabled development of complex vegetative and reproductive plant morphologies. Despite its profound evolutionary significance, the molecular programs involved in this transition from filamentous to triplanar meristematic plant growth are poorly understood. In this study, we used single-cell type transcriptomics to identify more than 4000 differentially expressed genes that distinguish uniplanar protonematal tip cells from multiplanar gametophore bud cells in the moss Physcomitrella patens. While the transcriptomes of both tip and bud cells show molecular signatures of proliferative cells, the bud cell transcriptome exhibits a wider variety of genes with significantly increased transcript abundances. Our data suggest that combined expression of genes involved in shoot patterning and asymmetric cell division accompanies the transition from uniplanar to triplanar meristematic growth in moss.

  14. The application of multi-shoots cultures in micropropagation of willow herb (Chamaenerion angustifolium (L. Scop.

    Dreger, Mariola


    Full Text Available Willow herb (Chamaenerion angustifolium (L. Scop. syn. Epilobium angustifolium L. from Onagraceae family is a valuable medicinal plant that has been used in the treatment of urogenital disorders including BPH (Benign Prostatic Hypertrophy. The raw material is a rich source of polyphenols as well as steroids, triterpenoids and fatty acids. The extracts show pharmacological activities: anti-androgen, anti-proliferative, anti-inflammatory, antioxidant, antibacterial and analgesic properties. Due to frequent interspecific hybridization, plants collected in the wild display a diverse and variable content of active compounds. This poses a challenge in obtaining high quality and homogenous raw material. Application of the in vitro cultures and micropropagation techniques may offer a solution for alternative methods of cultivation. This work presents preliminary results of the implementation of Ch. angustifolium in vitro cultures to obtain raw material for the first time. Sterile seedlings were donors of explants, which were used for induction of multi-shoots culture according to a modified Turker’s protocol. Six different genotypes (lines originating from root explants were chosen for clonal propagation. Efficiency of the elaborated method was 16 – 20 shoots per explants. Finally, over 3000 acclimatized plants were obtained and used for field crops.

  15. Regeneration of Blackgram (Vigna mungo L. on Changes of Hormonal Condition

    Shariful Alam MONY


    Full Text Available The study comprised of experiments for shoot regeneration and plantlet formation from cotyledonary node of Vigna mungo by culturing them on low concentration of BAP followed by transfer to hormone free MS medium. Cotyledonary node explants were cultured on different concentrations of BAP (0, 1, 2.5 and 50 mg l-1. Shoot regeneration occurred from cotyledonary nodes irrespective of the presence or absence of BAP in the medium. However, culture of cotyledonary node explants for 10 days on medium containing 1.0 mg l-1 BAP followed by transfer to hormone free medium gave higher number of shoots (9.33/explant compared to culture of the explants on hormone free medium for 15 days followed by transfer to medium containing 1.0 mg l-1 BAP (8.33/explants. The regenerated shoots were transferred to rooting medium supplemented with different concentrations of IBA and NAA. The high frequency (100.0% of rooting was observed with MS medium supplemented with 0.5 mg l-1 IBA. The rooted plants were transferred to pots for hardening.

  16. Plantlet Regeneration of Tartary Buckwheat (Fagopyrum tataricum Gaertn.) in Vitro Tissue Cultures.

    Wang, Cheng-Long; Dong, Xue-Ni; Ding, Meng-Qi; Tang, Yi-Xiong; Zhu, Xue-Mei; Wu, Yan-Min; Zhou, Mei-Liang; Shao, Ji-Rong


    Tartary buckwheat is an ancient annual dicotyledonous herb, which is widely distributed around the world, specifically in the high altitude area of southwestern China and in the hill region of Himalayan. The plantlet regeneration of tartary buckwheat via somatic embryogenesis or multiple shoot induction was investigated in two different tartary buckwheats, Yuanzi and Xichang. The regeneration ability of Yuanzi was better than Xichang tartary buckwheat, and the hypocotyls were better than cotyledons as tartary buckwheat plantlet regeneration explants via somatic embryogenesis. The most suitable medium for callus induction was Murashige and Skoog basal medium added 2 mg/L 2, 4- dichlorophenoxyacetic acid and 1 mg/L Kinetin, which could reach up to 98.96% callus induction percentage. The plantlet regeneration percentage from callus of tartary buckwheat could reach up to 55.77%, which induced on 2.0 mg/L Benzyladenine and 1.0 mg/L KT in MS basal medium. In addition, maximum of multiple shoot induction percentage was 69.05%, which was observed in case of Yuanzi tartary buckwheat in MS basal medium with added 3.0 mg/L 6-BA and 1.0 mg/L Thidiazuron. Roots induction of regenerated plants were achieved on 1/2 MS basal medium with added 1mg/L Indole-3-Butytric acid, which has 75% survival after transferred regenerated plants to soil under field conditions.

  17. Plants regenerated from mesophyll protoplasts of white mulberry



    Morus alba(white mulberry) mesophyll protoplasts were isolated from leaves of 30-45 day old sterile shoots,with protoplast yields of 2.5×107 g-1/F.W.after purification.The protoplasts were cultured in a modified K8P liquid medium containing 0.2mg/L 2,4-(2,4-Dichlorophenoxy acetic acid),1mg/L NAA(Naphthyl acetic acid) and 0.5mg/L BA(6-benzylaminopurine).A low plating density(5×104/ml) proved to be favourable to the division of protoplast-derived cells.The first division occurred 4 days after culture,and the division frequency reached 24% at 10 days.A number of cell colonies and microcalli formed in 6 weeks.The microcalli were transferred onto MSB medium with 0.5mg/L NAA and 0.5mg/L BA for further proliferation.Shoot formation was initiated when the calli of 3-4 mm in size were transferred onto MSB differentiation medium with 0.1mg/L NAA and 1mg/L BA.The frequency of shoot formation was 35%.The shoots of 4-5 cm in height were excised from the callus and rooted on half strength MS medium with 0.5 mg/L IBA and 0.1 mg/L BA.After transplantation into pots,the regenerated plants grew vigorously in the phytotron.

  18. Externally imposed electric field enhances plant root tip regeneration

    Kral, Nicolas; Hanna Ougolnikova, Alexandra


    Abstract In plants, shoot and root regeneration can be induced in the distinctive conditions of tissue culture (in vitro) but is also observed in intact individuals (in planta) recovering from tissue damage. Roots, for example, can regenerate their fully excised meristems in planta, even in mutants with impaired apical stem cell niches. Unfortunately, to date a comprehensive understanding of regeneration in plants is still missing. Here, we provide evidence that an imposed electric field can perturb apical root regeneration in Arabidopsis. Crucially, we explored both spatial and temporal competences of the stump to respond to electrical stimulation, by varying respectively the position of the cut and the time interval between excision and stimulation. Our data indicate that a brief pulse of an electric field parallel to the root is sufficient to increase by up to two‐fold the probability of its regeneration, and to perturb the local distribution of the hormone auxin, as well as cell division regulation. Remarkably, the orientation of the root towards the anode or the cathode is shown to play a role. PMID:27606066

  19. Evaluation of genetic homogeneity in tissue culture regenerates of Jatropha curcas L. using flow cytometer and DNA-based molecular markers.

    Rathore, Mangal S; Yadav, P; Mastan, Shaik G; Prakash, Ch R; Singh, A; Agarwal, Pradeep K


    The present investigation aimed to evaluate the reliability of in vitro propagation methods for elite genotypes of Jatropha curcas L., that maintain genetic integrity of tissue culture (TC) regenerates among two regeneration systems developed through direct shoot bud regeneration using nodal/apical shoot segments (protocol-A) and in vitro-derived leaves (protocol-B) as explants. Random amplified polymorphic DNA (RAPD), intersimple sequence repeat (ISSR), simple sequence repeat (SSR) molecular markers, and flow cytometery (FCM) were employed to evaluate genetic homogeneity in TC-regenerates at different passages of subcultures. RAPD markers showed genetic homogeneity in fifth-generation TC-regenerates of both protocols. ISSR markers showed genetic stability of leaf regenerates (protocol-B) at 10th generation. FCM analysis of TC-regenerates at 10th generation in protocol-B and at 20th generation in both protocols, showed stability of ploidy level. SSR assessment of TC-regenerates at 20th generation in both protocols confirmed genetic homogeneity. The results confirmed the genetic stability of the TC-regenerates and demonstrated the reliability of the regeneration systems developed so far using explants of two different origins, for large-scale multiplication of elite genotypes of Jatropha.

  20. Regeneration and reprogramming compared

    Robles Vanesa


    Full Text Available Abstract Background Dedifferentiation occurs naturally in mature cell types during epimorphic regeneration in fish and some amphibians. Dedifferentiation also occurs in the induction of pluripotent stem cells when a set of transcription factors (Oct4, Sox2, Klf4 and c-Myc is over expressed in mature cell types. Results We hypothesised that there are parallels between dedifferentiation or reprogramming of somatic cells to induced pluripotent stem cells and the natural process of dedifferentiation during epimorphic regeneration. We analysed expression levels of the most commonly used pluripotency associated factors in regenerating and non-regenerating tissue and compared them with levels in a pluripotent reference cell. We found that some of the pluripotency associated factors (oct4/pou5f1, sox2, c-myc, klf4, tert, sall4, zic3, dppa2/4 and fut1, a homologue of ssea1 were expressed before and during regeneration and that at least two of these factors (oct4, sox2 were also required for normal fin regeneration in the zebrafish. However these factors were not upregulated during regeneration as would be expected if blastema cells acquired pluripotency. Conclusions By comparing cells from the regeneration blastema with embryonic pluripotent reference cells we found that induced pluripotent stem and blastema cells do not share pluripotency. However, during blastema formation some of the key reprogramming factors are both expressed and are also required for regeneration to take place. We therefore propose a link between partially reprogrammed induced pluripotent stem cells and the half way state of blastema cells and suggest that a common mechanism might be regulating these two processes.

  1. Effect of Gamma Irradiation on Regeneration Capacity of Mangosteen Nodular Callus



    Full Text Available The research was conducted to determine the effect of gamma irradiation on regeneration capacity of mangosteed nodular callus. Nodular calli derived from a leaf as explants and cultured on MS medium containing combination of 2.2 µM benzilaminopurin (BAP and 2.27 µM tidiazuron (TDZ. Nodular calli were irradiated with 0 (control 5, 10, 15, 20, 25, 30, 35, and 40 Gy doses of gamma irradiation. After the irradiation, the calli were generated on woody plant medium (WPM, supplemented with 1.39 µM polyvinilpirolidon (PVP, 8 g.l-1 agar, 30 g.l-1 sucrose and 2.2 µM BAP concentration. Results showed that the irradiation influence the plant regeneration. Response dose of 50% (RD that could promote the nodular calli of shoot formation was the 25 Gy while that of the shoot number per nodular calli was the 21 Gy. The shoot number irradiated with total dose 5 Gy (9.1 shoot was higher than that of 0 Gy (8.6 shoot.

  2. An efficient in vitro plant regeneration of Dipteracanthus prostratus (Poir.) Nees.- a medicinal herb

    Jeyachandran Robert; Baskaran Xavier ravi; Cindrella Louis


    Objective: This is the first attempt for an efficient plant regeneration protocol through in vitro direct organogenesis for a valuable medicinal plant, Dipteracanthus prostratus using nodal segment. Methods: Multiple shoots were induced from nodal explants cultured on Murashige and Skoog medium supplemented with kinetin (KIN), 6-benzylaminopurine (BAP) and 1-Naphthaleneacetic acid (NAA). Results: Maximum shoot responses (80%) were obtained with kinetin at 1.0 mg-1. The rate of shoot multiplication was maintained in subsequent subculture on similar fresh culture medium. The highest shoot length (3.96cm) was obtained with seventy three percentages of shoots at 0.2 mg-1 NAA along with 1.0 mg-1 kinetin. Maximum length of root (3.63cm) was formed at 0.5 mg-1 IBA with significant responses (80%). Rooted plantlets were then transferred to perforated plastic cups and grown in the green house at 80% survival rate. Conclusions: The highest survival rate was noticed and this plant developmental protocol could be used for large- scale regeneration of D. prostratus.

  3. Efficient cryopreservation by droplet vitrification of pentaploid roses and the phenotype of regenerated plants

    Bożena Pawłowska


    Full Text Available Shoot tips from in vitro plants of four rose species were cryopreserved by the droplet vitrification method. Optimized conditions involved exposure to loading solution for 20 min, then treatment with plant vitrification solution (PVS2 for 20 min (Rosa agrestis, R. canina and R. dumalis or 30 min (R. rubiginosa followed by freezing in liquid nitrogen. Survival rate ranged from 78.3 to 95.1%, depending on the species. Regrowth rate of shoot tips was 50.5% for R. agrestis, 63.2% for R. rubiginosa, 71.4% for R. dumalis and 78% for R. canina. The preculture of donor plants in a medium with 0.25 µM sucrose facilitated the isolation of shoot tips and increased regrowth rate after cryopreservation. Plant regeneration was carried out in Murashige and Skoog medium with 1 µM 6-benzylaminopurine, 1.5 µM gibberellic acid and 0.087 M sucrose. Plants regenerated from cryopreserved shoot tips did not display morphological alterations in comparison with non-cryopreserved shoot tip – derived plants.

  4. Preculturing effect of thidiazuron on in vitro shoot multiplication and micropropagation round in Capparis decidua (Forsk.) an important multipurpose plant.

    Bukhari, Najat A W; Siddique, Iram; Perveen, Kahkashan


    An efficient protocol was developed for clonal multiplication of an important shrub: Capparis decidua (Forsk.) Edgew, through in vitro shoot induction and multiplication from nodal explants. Pretreatment of nodal explants in a liquid Murashige and Skoog (MS) medium augmented with various thidiazuron (TDZ) concentrations at relatively high levels (5-100 μM) for different time duration (4, 8, 12 and 16 d), proved a significant approach for in vitro shoot production. After an initial exposure time to TDZ, nodal explants were inoculated onto a MS basal medium devoid of TDZ for further induction and proliferation. The highest regeneration rate (85%), average number of shoots/explant (8.7 ± 0.22) and maximum shoot length (3.9 ± 0.33 cm) were obtained from the nodal explants exposed to 50 μM TDZ for 8 d. The nodal explants excised from the proliferated cultures of TDZ (50 μM) for 8 d were used as explants and showed an enhancement rate after next three round of in vitro propagation. Best results for rooting was obtained by ex vitro treatment of shoots with 200 μM indole-3-butyric acid (IBA) for 20 min. as it produced an average of 5.7 ± 0.41 roots per microshoot with 4.4 ± 0.39 cm root length in 84% shoots. Different planting substrates was tested for maximum survival of hardening off micropropagated plantlets and soilrite proved most effective than others as 97.1 ± 7.21 plantlets survived. All micropropagated plants grew well in natural conditions and showed similar morphology to the mother plant.

  5. Strategies for lung regeneration

    Thomas H. Petersen


    Full Text Available Due to the limited ability of the adult lung to regenerate and the frequency of lung disease, the lung is a tissue that can especially benefit from regenerative medicine. Prospects for lung regeneration have made great strides in the past year. In this review, we summarize recent progress and key challenges for approaches in lung regenerative medicine. With a focus on the matrix components critical for the development of regenerative lung tissues, we discuss possible cell sources for lung regeneration, key matrix effects on cell repopulation, and physical stimuli that will aid in the growth of lung tissues in vitro.

  6. Tooth regeneration: Current status

    Dadu Shifali


    Full Text Available Regeneration of a functional tooth has the potential to be a promising therapeutic strategy. Experiments have shown that with the use of principles of bioengineering along with adult stem cells, scaffold material, and signaling molecules, tooth regeneration is possible. Research work is in progress on creating a viable bioroot with all its support. A new culture needs to be created that can possibly provide all the nutrients to the stem cells. With the ongoing research, tissue engineering is likely to revolutionize dental health and well-being of people by regenerating teeth over the next decade.

  7. Tooth regeneration: current status.

    Dadu, Shifali S


    Regeneration of a functional tooth has the potential to be a promising therapeutic strategy. Experiments have shown that with the use of principles of bioengineering along with adult stem cells, scaffold material, and signaling molecules, tooth regeneration is possible. Research work is in progress on creating a viable bioroot with all its support. A new culture needs to be created that can possibly provide all the nutrients to the stem cells. With the ongoing research, tissue engineering is likely to revolutionize dental health and well-being of people by regenerating teeth over the next decade.

  8. Regeneration Heat Exchange

    J. Lin


    The original project goals were to establish the viability of the proposed gas turbine regenerator concept by performing the following tasks: (1) Perform detailed design of a working model of the regenerator concept. (2) Construct a ''bench-top'' model of the regenerator concept based upon the detail design. (3) Test the bench-top model and gather data to support the concept's viability. The project funding was used to acquire the tools and material to perform the aforementioned tasks.

  9. Clonal fidelity of chrysanthemum regenerated from long term cultures

    Jevremović Slađana


    Full Text Available Morphological characteristics of flowers of long term regenerated chrysanthemum, cv. "White Spider", after ten years of micropropagation are investigated. Shoot cultures are established and maintained more than ten years by stem segment culture on MS medium supplemented with BAP and NAA (1.0, 0.1 mgL-1, respectively. Rooting of shoots (100 % has done on MS medium without hormones and it was very successful after ten years, as well as, after two or eight years of micropropagation. Acclimation of rooted chrysanthemum plantlets at greenhouse conditions was excellent and after appropriate photoperiod "in vitro" plants flowered 90.3 % and have the same flower color, shape and size as mother plants. Flower color changes of "in vitro" plants are observed during another flowering cycle one year after acclimatization. Observed variations of chrysanthemum flowers could be attributed to epigenetic factors.

  10. Surface disinfection procedure and in vitro regeneration of grapevine (Vitis vinifera L.) axillary buds.

    Lazo-Javalera, M F; Troncoso-Rojas, R; Tiznado-Hernández, M E; Martínez-Tellez, M A; Vargas-Arispuro, I; Islas-Osuna, M A; Rivera-Domínguez, M


    Establishment of an efficient explants surface disinfection protocol is essential for in vitro cell and tissue culture as well as germplasm conservation, such as the case of Grapevine (Vitis spp.) culture. In this research, different procedures for disinfection and regeneration of field-grown grapevine cv. 'Flame seedless' axillary buds were evaluated. The buds were disinfected using either NaOCl or allyl, benzyl, phenyl and 2-phenylethyl isothiocyanates. Two different media for shooting and four media for rooting were tested. Shoot and root development per buds were registered. The best disinfection procedure with 90 % of tissue survival involved shaking for 60 min in a solution containing 20 % Clorox with 50 drops/L Triton(®) X-100. These tissues showed the potential to regenerate a complete plant. Plant regeneration was conducted using full strength Murashigue and Skoog (MS) medium supplemented with 8 µM benzyl aminopurine for shoot induction and multiplication, whereas rooting was obtained on half strength MS supplemented with 2 mg L(-1) of indole-3-butyric acid and 200 mg L(-1) of activated charcoal. In this work, it was designed the protocols for obtaining sterile field-grown grapevine buds and in vitro plant development. This methodology showed potential to produce vigorous and healthy plants in 5 weeks for clonal grapevine propagation. Regenerated plants were successfully established in soil.

  11. Agrobacterium-mediated transformation of apple (Malus x domestica Borkh.): an assessment of factors affecting regeneration of transgenic plants.

    De Bondt, A; Eggermont, K; Penninckx, I; Goderis, I; Broekaert, W F


    We have previously developed a protocol for efficient gene transfer and regeneration of transgenic calli following cocultivation of apple (cv. Jonagold) explants with Agrobacterium tumefaciens (De Bondt et al. 1994, Plant Cell Reports 13: 587-593). Now we report on the optimization of postcultivation conditions for efficient and reproducible regeneration of transgenic shoots from the apple cultivar Jonagold. Factors which were found to be essential for efficient shoot regeneration were the use of gelrite as a gelling agent and the use of the cytokinin-mimicing thidiazuron in the selective postcultivation medium. Improved transformation efficiencies were obtained by combining the hormones thidiazuron and zeatin and by using leaf explants from in vitro grown shoots not older than 4 weeks after multiplication. Attempts to use phosphinothricin acetyl transferase as a selectable marker were not successful. Using selection on kanamycin under optimal postcultivation conditions, about 2% of the leaf explants developed transgenic shoots or shoot clusters. The presence and expression of the transferred genes was verified by β-glucuronidase assays and Southern analysis. The transformation procedure has also been succesfully applied to several other apple cultivars.

  12. Notch regulates blastema proliferation and prevents differentiation during adult zebrafish fin regeneration.

    Münch, Juliane; González-Rajal, Alvaro; de la Pompa, José Luis


    Zebrafish have the capacity to regenerate several organs, including the heart and fins. Fin regeneration is epimorphic, involving the formation at the amputation plane of a mass of undifferentiated, proliferating mesenchymal progenitor-like cells, called blastema. This tissue provides all the cell types that form the fin, so that after damage or amputation the fin pattern and structure are fully restored. How blastema cells remain in this progenitor-like state is poorly understood. Here, we show that the Notch pathway plays an essential role during fin regeneration. Notch signalling is activated during blastema formation and remains active throughout the regeneration process. Chemical inhibition or morpholino-mediated knockdown of Notch signalling impairs fin regeneration via decreased proliferation accompanied by reduced expression of Notch target genes in the blastema. Conversely, overexpression of a constitutively active form of the Notch1 receptor (N1ICD) in the regenerating fin leads to increased proliferation and to the expansion of the blastema cell markers msxe and msxb, as well as increased expression of the proliferation regulator aldh1a2. This blastema expansion prevents regenerative fin outgrowth, as indicated by the reduction in differentiating osteoblasts and the inhibition of bone regeneration. We conclude that Notch signalling maintains blastema cells in a plastic, undifferentiated and proliferative state, an essential requirement for fin regeneration.

  13. Neuregulin-1 signaling is essential for nerve-dependent axolotl limb regeneration.

    Farkas, Johanna E; Freitas, Polina D; Bryant, Donald M; Whited, Jessica L; Monaghan, James R


    The Mexican axolotl (Ambystoma mexicanum) is capable of fully regenerating amputated limbs, but denervation of the limb inhibits the formation of the post-injury proliferative mass called the blastema. The molecular basis behind this phenomenon remains poorly understood, but previous studies have suggested that nerves support regeneration via the secretion of essential growth-promoting factors. An essential nerve-derived factor must be found in the blastema, capable of rescuing regeneration in denervated limbs, and its inhibition must prevent regeneration. Here, we show that the neuronally secreted protein Neuregulin-1 (NRG1) fulfills all these criteria in the axolotl. Immunohistochemistry and in situ hybridization of NRG1 and its active receptor ErbB2 revealed that they are expressed in regenerating blastemas but lost upon denervation. NRG1 was localized to the wound epithelium prior to blastema formation and was later strongly expressed in proliferating blastemal cells. Supplementation by implantation of NRG1-soaked beads rescued regeneration to digits in denervated limbs, and pharmacological inhibition of NRG1 signaling reduced cell proliferation, blocked blastema formation and induced aberrant collagen deposition in fully innervated limbs. Taken together, our results show that nerve-dependent NRG1/ErbB2 signaling promotes blastemal proliferation in the regenerating limb and may play an essential role in blastema formation, thus providing insight into the longstanding question of why nerves are required for axolotl limb regeneration.

  14. Chemical genetics and regeneration.

    Sengupta, Sumitra; Zhang, Liyun; Mumm, Jeff S


    Regeneration involves interactions between multiple signaling pathways acting in a spatially and temporally complex manner. As signaling pathways are highly conserved, understanding how regeneration is controlled in animal models exhibiting robust regenerative capacities should aid efforts to stimulate repair in humans. One way to discover molecular regulators of regeneration is to alter gene/protein function and quantify effect(s) on the regenerative process: dedifferentiation/reprograming, stem/progenitor proliferation, migration/remodeling, progenitor cell differentiation and resolution. A powerful approach for applying this strategy to regenerative biology is chemical genetics, the use of small-molecule modulators of specific targets or signaling pathways. Here, we review advances that have been made using chemical genetics for hypothesis-focused and discovery-driven studies aimed at furthering understanding of how regeneration is controlled.

  15. Callus cell, shoot and stem proliferation data from pineapple crown and banana inflorescence in vitro: Biochemical and antioxidant properties

    ABM Sharif Hossain


    Full Text Available The data article contains the experimental data and images on the callus cell, shoot and stem proliferation from pineapple crown slice and banana inflorescence in vitro. Investigated data are related to the research article “Effects of benzylaminopurine and naphthalene acetic acid on proliferation and shoot growth of pineapple (Ananas comosus L. Merr in vitro” Alsaif et al. (2011 [1] and “Plantlet Production through Development of Competent Multiple Meristem Cultures from Male Inflorescence of Banana, Musa acuminta cv. ׳Pisang Mas׳(AA” Wirakarnain et al. (2008 [2]. In the experimental data 1, physiological, (shoot weight, number length and stem proliferation biochemical (total sugar and chlorophyll and nutritional ((K+ and NO3− data using BAP, MS medium and NAA growth regulators in pineapple have been explored. In the experimental data 2, physiological, (callus weight, shoot number and length biochemical (total sugar, chlorophyll, total phenol, DPPH and nutritional (K+ and NO3− data employing BAP +IAA, MS medium and NAA growth regulators in banana have been exhibited. Overall quantitative measurement was observed by Spectrophotometer. In the experimental data, BAP was shown the best effective hormone for the both pineapple and banana explants regeneration.

  16. Annual shoot growth components related to growth of Pinus brutia.

    Isik, Fikret; Isik, Kani; Yildirim, Tolga; Li, Bailian


    Shoot elongation patterns of Pinus brutia Ten. were studied in six natural populations and 10 open-pollinated families within each population. The data were collected from a provenance-progeny trial that was thinned at Ages 13 and 17 years. Annual height increment was partitioned into first flush (spring shoot) and subsequent flushes (summer shoots) and the contribution of each to annual height increment was measured from Ages 7 to 17. Spring shoot elongation patterns were similar in all populations and families for 9 out of 10 years. In contrast, at all ages, populations differed significantly in total summer shoot growth and number of summer flushes. Families within populations differed in number of summer flushes in 7 out of 10 years. Summer shoot growth was the major cause of the differences in annual height growth among the six populations. Significant and high correlations were observed between summer shoot growth at Ages 7 to 12 and height at Age 13. A population from near the middle of the species' altitudinal range had more summer flushes than populations from higher or lower elevations, indicating an opportunistic growth pattern. Compared with mid-elevation populations, low- and high-elevation populations had more conservative growth patterns that depended mainly on growth of spring shoots. We conclude that summer shoot growth can serve as an explanatory variable to predict height growth of populations. Differences in shoot elongation patterns among Pinus brutia populations may be useful for selecting seed sources and for gene conservation programs.

  17. Bamboo shoots: a novel source of nutrition and medicine.

    Singhal, Poonam; Bal, Lalit Mohan; Satya, Santosh; Sudhakar, P; Naik, S N


    Bamboos, a group of large woody grasses belonging to the family Poaceae and subfamily Bambusoideae, are much talked about for their contribution to the environment. However, the food potential of Bamboo shoot per se remains unexploited. Literature on the nutritional and medicinal potential of bamboo shoots is scarce. This paper therefore provides insight on bamboo shoot as a food resource. Various edible species and exotic food products (fermented shoots, pickle, etc.) and recipes of bamboo shoots (bamboo beer, bamboo cookies) are consumed worldwide. Change in nutritional composition of different species of bamboo shoots with processing has also been reviewed. Bamboo shoots possess high protein, moderate fiber, and less fat content. They are also endowed for having essential amino acids, selenium, a potent antioxidant, and potassium, a healthy heart mineral. Occurrence of taxiphyllin, a cyanogenic glycoside in raw shoots, and its side effect on human health calls for the demand to innovate processing ways using scientific input to eliminate the toxic compound without disturbing the nutrient reserve. Lastly, the paper also reviews the utilization of medicinal properties acquired by bamboo shoot. Using the traditional knowledge, pharmaceutical preparations of bamboo shoots like bamboo salt, bamboo vinegar, bamboo extracts for diabetes and cholesterol control, etc. are now gaining importance. Further investigation is required by the researchers to make novel nutraceutical products and benefit the society.

  18. In vitro regeneration of solanum aethiopicum L. (scarlet eggplant), an african vegetable crop with potential ornamental value

    Successful in vitro regeneration of plantlets was obtained from shoot tips of five Solanum aethiopicum (African eggplants) accessions evaluated in two media, M1 and M2. The M1 medium consisted of Murashige and Skoog (MS) basal salt mixture supplemented with 20 g/L sucrose, 0.75 g/L MgCl2, and 2 g/L ...

  19. Influence of plant growth regulators on callus mediated regeneration and secondary metabolites synthesis in Withania somnifera (L.) Dunal.

    Chakraborty, Nilanjan; Banerjee, Debarupa; Ghosh, Moumita; Pradhan, Prakash; Gupta, Namrata Shanu; Acharya, Krishnendu; Banerjee, Maitreyi


    Withania somnifera (L.) Dunal, is an important medicinal plant being the source of extremely important compounds like withanolides and withaferin. Influence of different plant growth regulators (PGRs) were evaluated for induction of callus, callus mediated regeneration and production of secondary metabolites in them. Explants for callusing were collected from plants grown in vitro and maximum callusing (98 %) was obtained on MS medium supplemented with a combination of 2,4-dichlorophenoxy acetic acid (2,4-D) (0.5 mg l(-1)) and kinetin (KN) (0.2 mg l(-1)). Among different types of calli, best shoot regeneration was observed on green, compact calli produced on MS medium with a combination of 6-benzylamino purine (BAP) and indole butyric acid (IBA). MS medium supplemented with BAP (2 mg l(-1)) showed highest frequency (98 %) of shoot bud regeneration. The micro-shoots were efficiently rooted on MS media supplemented with 0.5 mg l(-1) IBA. Rooted plants were transferred to soil-vermi-compost (1:3; w/w) medium in greenhouse for acclimatization. Presence of withanolide A and withaferin A in calli was validated through high performance thin layer chromatography (HPTLC). It was interesting to observe that the PGRs showed significant influence on the secondary metabolites production in callus and 2,4-D having the least effect. Histological studies revealed the origin of shoot tip in the callus during regeneration.

  20. Optimal Media for In-Vitro Regeneration of Two Local Genotypes of Chili Pepper (Capsicum annuum L. from West Sumatera

    - Renfiyeni


    Full Text Available Genetic engineering strategy in chilli pepper (Capsicum annuum L. has been applied so far in order to improve its genetic capacity for instance against some important diseases. This strategy needs an established system for calli preparation as well as transformant regeneration. In most cases, this necessity is genotype dependent especially for some local genotypes. Based on this, we optimized media for calli induction, shoot and root regeneration of our three local cultivars namely Kampung, Kopay and Trisula. Media combinations basically were composed of MS  and combined with some growth factors for instance IAA, BAP, NAA and TDZ with different combinations for each calli induction, shoot and root regeneration. All media compositions were supplemented with 30 GL-1 sucrose. The best medium for calli induction was MS media supplemented with 4 mgL-1 BAP, 0.5 mgL-1 IAA and L2 vitamin (Thiamin-HCl and Pyrodoxine-HCl. While the best medium for shoot induction and elongation was MS supplemented with 1mgL-1 BAP, 5 mgL-1 AgNO3, 2 mgL-1 GA3, 2 mgL-1 Calcium Pantotenate and L2 vitamin.  Furthermore, the best medium for root induction and elongation was WPM (Woody Plant Medium supplemented with 0.4 mgL-1 NAA. This finding should provide optimal media for calli induction and shoot-root regeneration for the three local cultivars Kampung, Kopay and Trisula.

  1. Air regenerating and conditioning

    Grishayenkov, B. G.


    Various physicochemical methods of regenerating and conditioning air for spacecraft are described with emphasis on conditions which affect efficiency of the system. Life support systems used in closed, hermetically sealed environments are discussed with references to actual application in the Soviet Soyuz and Voskhod manned spacecraft. Temperature and humidity control, removal of carbon dioxide, oxygen regeneration, and removal of bacteria and viruses are among the factors considered.

  2. Nanostructured Biomaterials for Regeneration**

    Wei, Guobao; Ma, Peter X.


    Biomaterials play a pivotal role in regenerative medicine, which aims to regenerate and replace lost/dysfunctional tissues or organs. Biomaterials (scaffolds) serve as temporary 3D substrates to guide neo tissue formation and organization. It is often beneficial for a scaffolding material to mimic the characteristics of extracellular matrix (ECM) at the nanometer scale and to induce certain natural developmental or/and wound healing processes for tissue regeneration applications. This article...

  3. Efficient callus formation and plant regeneration are heritable characters in sugar beet (Beta vulgaris L.).

    Kagami, Hiroyo; Taguchi, Kazunori; Arakawa, Takumi; Kuroda, Yosuke; Tamagake, Hideto; Kubo, Tomohiko


    Obtaining dedifferentiated cells (callus) that can regenerate into whole plants is not always feasible for many plant species. Sugar beet is known to be recalcitrant for dedifferentiation and plant regeneration. These difficulties were major obstacles for obtaining transgenic sugar beets through an Agrobacterium-mediated transformation procedure. The sugar beet line 'NK-219mm-O' is an exceptional line that forms callus efficiently and is easy to regenerate, but the inheritance of these characters was unknown. Another concern was whether these characters could coexist with an annual habitat that makes it possible to breed short life-cycle sugar beet suitable for molecular genetic analysis. Five sugar beet lines including NK-219mm-O were crossed with each other and subjected to in vitro culture to form callus. F1s with a NK-219mm-O background generally formed callus efficiently compared to the others, indicating that efficient callus formation is heritable. The regeneration potential was examined based on the phenotypes of calli after placement on regeneration medium. Five phenotypes were observed, of which two phenotypes regenerated shoots or somatic embryo-like structures. Vascular differentiation was evident in regenerable calli, whereas non-regenerable calli lacked normally developed vascular tissues. In a half-diallel cross, the callus-formation efficiency and the regeneration potential of reciprocal F1s progeny having a NK-219mm-O background were high. Finally, we crossed NK-219mm-O with an annual line that had a poor in vitro performance. The callus-formation efficiency and the regeneration potential of reciprocal F1 were high. The regenerated plants showed an annual habitat. Efficient callus formation and the high plant regeneration potential of NK-219mm-O were inherited and expressed in the F1. The annual habitat does not impair these high in vitro performances.

  4. Dilong: Role in Peripheral Nerve Regeneration

    Yung-Ming Chang


    Full Text Available Dilong, also known as earthworm, has been widely used in traditional Chinese medicine (TCM for thousands of years. Schwann cell migration and proliferation are critical for the regeneration of injured nerves and Schwann cells provide an essentially supportive role for neuron regeneration. However, the molecular mechanisms of migration and proliferation induced by dilongs in Schwann cells remain unclear. Here, we discuss the molecular mechanisms that includes (i migration signaling, MAPKs (mitogen-activated protein kinases, mediated PAs and MMP2/9 pathway; (ii survival and proliferative signaling, IGF-I (insulin-like growth factor-I-mediated PI3K/Akt pathways and (iii cell cycle regulation. Dilong stimulate RSC96 cell proliferation and migration. It can induce phosphorylation of ERK1/2 and p38, but not JNK, and activate the downstream signaling expression of PAs (plasminogen activators and MMPs (matrix metalloproteinases in a time-dependent manner. In addition, Dilong stimulated ERK1/2 and p38 phosphorylation was attenuated by pretreatment with chemical inhibitors (U0126 and SB203580, and small interfering ERK1/2 and p38 RNA, resulting in migration and uPA-related signal pathway inhibition. Dilong also induces the phosphorylation of IGF-I-mediated PI3K/Akt pathway, activates protein expression of PCNA (proliferating cell nuclear antigen and cell cycle regulatory proteins (cyclin D1, cyclin E and cyclin A in a time-dependent manner. In addition, it accelerates G1-phase progression with earlier S-phase entry and significant numbers of cells entered the S-phase. The siRNA-mediated knockdown of PI3K that significantly reduces PI3K protein expression levels, resulting in Bcl2 survival factor reduction, revealing a marked blockage of G1 to S transition in proliferating cells. These results reveal the unknown RSC96 cell migration and proliferation mechanism induced by dilong, which find use as a new medicine for nerve regeneration.


    Loeb, J


    1. A method is given which allows us to measure the influence of the mass of a leaf upon the quantity of shoots regenerated in an isolated piece of stem. This method consists in isolating a piece of stem with only two leaves left at the basal node and then splitting the stem lengthwise so that each half has one basal leaf. By leaving one leaf intact while the size of the sister leaf is reduced, the influence of the mass of the leaf upon the quantity of shoots regenerated by the stem can be measured. 2. This method has yielded the result that the mass of shoots regenerated at the apex of such a piece of stem increases under equal conditions and in equal time with the mass of the leaf, and is approximately proportional to the mass of the leaf. 3. Such an influence of the mass of the leaf upon the mass of shoots produced by the stem is only intelligible on the assumption that the growth of the regenerating shoot occurs at the expense of material furnished by the basal leaf. 4. This assumption is supported by two facts: first, that in the dark this influence of the leaf disappears more or less completely; and, second, that a leaf attached to the base of a regenerating stem after some time weighs markedly less than does a sister leaf completely detached from the stem, but otherwise under equal conditions. 5. This latter fact that a leaf when attached to the base of an excised piece of stem wilts more rapidly than when completely isolated is the reason that the proportionality between mass of a basal leaf and mass of shoot regenerated at the apex of an isolated piece of stem cannot always be demonstrated with the same degree of accuracy as the proportionality between the mass of completely isolated leaves and the mass of shoots they produce. 6. The material furnished by the leaf to the stem is not restricted to water but includes also the solutes, since not only the fresh weight but also the dry weight of the shoot regenerated by a piece of stem increases with the mass

  6. Chemical constituents of Caragana bungei shoots

    Daniil N. Olennikov


    Full Text Available The phytochemical study of flowering shoots of Caragana bungei Ledeb., Fabaceae, collected in Tuva Republic (Russian Federation resulted in the isolation of sixteen compounds identified as β-sitosterol, β-sitosterol-3-O-glucoside, umbelliferone, kaempferol, quercetin, isorhamnetin-3-O-glucoside, isoquercitrin, rutin, narcissin, nicotiflorin, caffeic acid, 3-O-caffeoylquinic acid, 5-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, gallic acid and sucrose. The structures of the compounds were established by spectral analyses. This is the first phytochemical investigation of C. bungei. The nicotiflorin, phenylpropanoids and gallic acid were isolated from the Caragana genus for the first time.

  7. Vegetative propagation of Quercus suber L. by somatic embryogenesis. II. Plant regeneration from selected cork oak trees.

    Hernández, I; Celestino, C; Alegre, J; Toribio, M


    The regeneration of somatic seedlings from selected 100-year-old cork oak trees is reported. The induction of somatic embryogenesis from leaves of epicormic shoots was significantly affected by genotype, harvesting time and their interaction. Leaves from all five selected trees produced somatic embryos when the segments of branches used as sources of epicormic shoots were collected in May. Genotype, but not the level of photosynthetically active radiation, affected the proliferation of the embryogenic lines and the number of detachable embryos that could be obtained from them. Genotype also affected several steps leading to conversion of somatic embryos, from germination to complete acclimatisation of somatic seedlings. Almost 40% of the somatic embryos from all lines germinated, showing coordinated root and shoot growth. Although the mean percentage of recovery for the whole process was low, plants could be regenerated from four of the five trees tested.

  8. Estrogen signaling in the proliferative endometrium: implications in endometriosis

    Rita de Cássia Pereira da Costa e Silva


    Full Text Available SUMMARY Even though the physiological role of estrogen in the female reproductive cycle and endometrial proliferative phase is well established, the signaling pathways by which estrogen exerts its action in the endometrial tissue are still little known. In this regard, advancements in cell culture techniques and maintenance of endometrial cells in cultures enabled the discovery of new signaling mechanisms activated by estrogen in the normal endometrium and in endometriosis. This review aims to present the recent findings in the genomic and non-genomic estrogen signaling pathways in the proliferative human endometrium specifically associated with the pathogenesis and development of endometriosis.

  9. TCPs, WUSs, and WINDs: families of transcription factors that regulate shoot meristem formation, stem cell maintenance, and somatic cell differentiation.

    Ikeda, Miho; Ohme-Takagi, Masaru


    In contrast to somatic mammalian cells, which cannot alter their fate, plant cells can dedifferentiate to form totipotent callus cells and regenerate a whole plant, following treatment with specific phytohormones. However, the regulatory mechanisms and key factors that control differentiation-dedifferentiation and cell totipotency have not been completely clarified in plants. Recently, several plant transcription factors that regulate meristem formation and dedifferentiation have been identified and include members of the TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP), WUSCHEL (WUS), and WOUND INDUCED DEDIFFERENTIATION (WIND1) families. WUS and WIND positively control plant cell totipotency, while TCP negatively controls it. Interestingly, TCP is a transcriptional activator that acts as a negative regulator of shoot meristem formation, and WUS is a transcriptional repressor that positively maintains totipotency of the stem cells of the shoot meristem. We describe here the functions of TCP, WUS, and WIND transcription factors in the regulation of differentiation-dedifferentiation by positive and negative transcriptional regulators.

  10. Transgenic plants from shoot apical meristems of Vitis vinifera L. "Thompson Seedless" via Agrobacterium-mediated transformation.

    Dutt, M; Li, Z T; Dhekney, S A; Gray, D J


    Shoot apical meristem explants of Vitis vinifera "Thompson Seedless" were used for Agrobacterium-mediated genetic transformation. It was determined that the meristems had to be subjected to a dark growth phase then wounded to obtain transgenic plants. Morphological and histological studies illustrated the role of wounding to expose apical meristem cells for transformation. A bifunctional egfp/nptII fusion gene was used to select kanamycin resistant plants that expressed green fluorescent protein (GFP). Kanamycin at a concentration of 16 mg L(-1) in selection medium resulted in recovery of non-chimeric transgenic plants that uniformly expressed GFP, whereas 8 mg L(-1) kanamycin allowed non-transgenic and/or chimeric plants to develop. Polymerase chain reaction (PCR) and Southern blot analyses confirmed the presence of transgenes and their stable integration into the genome of regenerated plants. Up to 1% of shoot tips produced stable transgenic cultures within 6 weeks of treatment, resulting in a total of 18 independent lines.

  11. Opposite metabolic responses of shoots and roots to drought

    Gargallo-Garriga, Albert; Sardans, Jordi; Pérez-Trujillo, Míriam; Rivas-Ubach, Albert; Oravec, Michal; Vecerova, Kristyna; Urban, Otmar; Jentsch, Anke; Kreyling, Juergen; Beierkuhnlein, Carl; Parella, Teodor; Peñuelas, Josep


    Shoots and roots are autotrophic and heterotrophic organs of plants with different physiological functions. Do they have different metabolomes? Do their metabolisms respond differently to environmental changes such as drought? We used metabolomics and elemental analyses to answer these questions. First, we show that shoots and roots have different metabolomes and nutrient and elemental stoichiometries. Second, we show that the shoot metabolome is much more variable among species and seasons than is the root metabolome. Third, we show that the metabolic response of shoots to drought contrasts with that of roots; shoots decrease their growth metabolism (lower concentrations of sugars, amino acids, nucleosides, N, P, and K), and roots increase it in a mirrored response. Shoots are metabolically deactivated during drought to reduce the consumption of water and nutrients, whereas roots are metabolically activated to enhance the uptake of water and nutrients, together buffering the effects of drought, at least at the short term.

  12. Accuracy of Skill Performance in the Basketball Free Throw Shooting

    Igawa Shoji


    Full Text Available The purpose of this study were to investigates how timing of shot of skilled player and assess performance accuracy of free throw shooting. Ten college students participated in this study (5 skilled players, and 5 naïve participants aged 18-23 years. They performed free throw shooting at 10 times. Shooting seen was recorded three cameras and analyzed shooting successful rate, off-target distance (the distance between the basketball through point and the center of the goal and shot timing. Shot timing was not significant difference. Shooting successful rate of skilled players was higher than unskilled players. Offtarget distance of skilled players was significant smaller than naive player. Consequently, skilled player is possible to aim at the center of the goal and shooting near the center of goal.

  13. MARCKS-Like Protein is an Initiating Molecule in Axolotl Appendage Regeneration

    Sugiura, Takuji; Wang, Heng; Barsacchi, Rico; Simon, Andras; Tanaka, Elly M.


    Identifying key molecules that launch regeneration has been a long sought goal. Multiple regenerative animals show an initial wound-associated proliferative response that transits into sustained proliferation if a significant portion of the body part has been removed 1-3 . In the axolotl, appendage amputation initiates a round of wound-associated cell cycle induction followed by continued proliferation that is dependent on nerve-derived signals 4,5 . A wound-associated molecule that triggers ...

  14. Arabidopsis brassinosteroid biosynthetic mutant dwarf7-1 exhibits slower rates of cell division and shoot induction

    Schulz Burkhard


    Full Text Available Abstract Background Plant growth depends on both cell division and cell expansion. Plant hormones, including brassinosteroids (BRs, are central to the control of these two cellular processes. Despite clear evidence that BRs regulate cell elongation, their roles in cell division have remained elusive. Results Here, we report results emphasizing the importance of BRs in cell division. An Arabidopsis BR biosynthetic mutant, dwarf7-1, displayed various characteristics attributable to slower cell division rates. We found that the DWARF4 gene which encodes for an enzyme catalyzing a rate-determining step in the BR biosynthetic pathways, is highly expressed in the actively dividing callus, suggesting that BR biosynthesis is necessary for dividing cells. Furthermore, dwf7-1 showed noticeably slower rates of callus growth and shoot induction relative to wild-type control. Flow cytometric analyses of the nuclei derived from either calli or intact roots revealed that the cell division index, which was represented as the ratio of cells at the G2/M vs. G1 phases, was smaller in dwf7-1 plants. Finally, we found that the expression levels of the genes involved in cell division and shoot induction, such as PROLIFERATING CELL NUCLEAR ANTIGEN2 (PCNA2 and ENHANCER OF SHOOT REGENERATION2 (ESR2, were also lower in dwf7-1 as compared with wild type. Conclusions Taken together, results of callus induction, shoot regeneration, flow cytometry, and semi-quantitative RT-PCR analysis suggest that BRs play important roles in both cell division and cell differentiation in Arabidopsis.


    I. Roostika


    Full Text Available Pruatjan (Pimpinella pruatjan Molk. is an Indonesian endangered plant which has various medicinal properties such as aphrodisiac, diuretic, and tonic. The plant is commonly harvested from its natural habitat, therefore it becomes endangered. Regeneration of pruatjan through organogenesis has been studied, but its shoot multiplication was very low (5 shoots per explant. The study aimed to investigate the best regeneration technique of pruatjan through somatic embryogenesis. This research was conducted at the tissue culture laboratory, Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development in 2004-2005. Callus formation of pruatjan was induced from the petioles and leaves in Driver and Kuniyaki’s (DKW based medium containing 2,4-D combined with picloram at the level of 0.5, 1.0, 1.5, and 1.5 ppm. Embryogenic calli were then transferred into embryo development medium in two ways. First, they were directly transferred into media containing IBA/NAA at the level of 0.5, 1.0, and 1.5 ppm. Second, they were indirectly transferred into media containing 2.0 ppm 2,4-D and 0.3% casein hydrolysate prior to the IBA/ NAA media. Parameters evaluated were fresh weight, dry weight, time initiation of embryogenic callus formation, and total number of embryos. The result showed that calli of pruatjan were successfully induced from the petioles and leaves. The best calli were induced from the leaves in the DKW medium containing 2.0 ppm 2,4-D and 0.5 ppm picloram. Embryo development of the calli was best if they were first grown in the media containing 2.0 ppm 2,4-D and 0.3% casein hydrolysate then transferred to the IBA/NAA media. The total number of somatic embryos was counted up to 103 on the medium containing 1.5 ppm IBA. This study indicated that pruatjan somatic embryogenesis regeneration required three different media, i.e. for callus induction, development and maturation, and for

  16. Evaluation of the tolerance to Finale® in the germination and regeneration of Cuban rice varieties (IACuba-17 and IACuba-19

    Daymí Abreu


    Full Text Available Selection agent used during the shoot selection has an important role on the transgenic plant generation efficiency. In this work, the tolerance to the herbicide Finale® in two Cuban rice cultivars, IACuba17 and IACuba-19 was evaluated, and determined that 10 days exposure to 5 and 10 mg.l-1 of Finale® were enough to avoid seedlings of IAC-17 and IAC-19, respectively. Cultivated calluses (0, 2, 4 and 6 days in the absence of Finale®in the regeneration medium were used to evaluate the minimal concentration of Finale®that totally inhibits shoot regeneration. Pre-induced calluses cultured during two days and 3 mg.l-1 of Finale® in the regeneration medium was the most efficient combination to select shoots during the generation of transgenic plants resistant to the herbicide. Our shoot selection procedure reduces to 3 weeks the time to obtain shoots during the generation of transgenic rice plants. Key words: germination, mature seeds, Oryza, phosphinothricin, regeneration, selection markers

  17. Preliminary Results from Simulations of Temperature Oscillations in Stirling Engine Regenerator Matrices

    Andersen, Stig Kildegård; Carlsen, Henrik; Thomsen, Per Grove


    The objective of this study has been to create a Stirling engine model for studying the effects of regenerator matrix temperature oscillations on Stirling engine performance. A one-dimensional model with axial discretisation of engine components has been formulated using the control volume method....... The model contains a system of ordinary differential equations (ODEs) derived from mass and energy balances for gas filled control volumes and energy balances for regenerator matrix control masses. Interpolation methods with filtering properties are used for state variables at control volume interfaces...... shooting method. It has been found possible to accurately solve the stiff ODE system that describes the coupled thermodynamics of the gas and the regenerator matrix and to reliably find periodic steady state solutions to the model. Preliminary results indicate that the regenerator matrix temperature...

  18. Plant regeneration from petiole segments of some species in tissue culture

    Krystyna Klimaszewska


    Full Text Available The regeneration ability of 21 plant species belonging to 14 families was tested. The method of tissue culture in vitro was applied, on basic MS medium with an addition of growth regulators from the auxin and cytokinin groups. From among the investigated plant groups Peperomia scandens and Caladium × hortulanum were capable of plant regeneration, Passiilora coerulea regenerated shoots, Hedera helix, Begonia glabra, Coleus blumei, Fuchsia hybrida, Passiflora suberosa and Peperomia eburnea formed callus and roots, Kalanchoe blossfeldiana, Pelargonium grandiflorum, P. peltatum, P. radula, Coleus shirensis and Magnolia soulangeana produced callus, Philodendron scandens, Rhododendron smirnovii, Hibiscus rosa-sinensis, Coprosma baueri, Cestrum purpureum and Solanum rantonnetii did not exhibit any regeneration reactions.

  19. [Establishment and optimization of the regeneration system for common dandelion (Taraxacum officinale Weber)].

    Chen, Hua; Li, Ping; Liu, Jing; Li, Yin-Xin


    A protocol is presented for direct and indirect regeneration of common dandelion (Taraxacum officinale Weber) from leaf and petiole explants. Multiple shoots were obtained on MS medium containing 0.2 mg/L IAA and 1 mg/L TDZ. For indirect regeneration, fragile calli were obtained from leaf and petiole explants on MS medium supplemented with 0.5 mg/L 2,4-D and 2.0 mg/L 6-BA. Regenerated plantlets were obtained when these calli were cultured on MS medium containing 1.0 mg/L 6-BA. Random amplified polymorphic DNA (RAPD) analysis of nine regenerated plantlets revealed 61 scorable bands from 10 primers, including three specific bands.

  20. In vitro regeneration from protocorms in Dendrobium aqueum Lindley – An imperiled orchid

    Selvaraju Parthibhan


    Full Text Available An efficient in vitro plant regeneration protocol from protocorms of Dendrobium aqueum was developed. The uniformly developed protocorms (in vitro origin having shoot initials were cultured on half macro strength MS medium (1/2 MS supplemented with cytokinins (BA, 2iP, KIN and TDZ at 1, 3, 5, 7, 10 mg l−1, natural additives (BP and CW at 1%, 3%, 5%, 7%, 10% and auxins (IBA, NAA, 2,4-D at 1, 3, 5, 7, 10 mg l−1 to study their efficacy on complete plant development. A maximum of 9.4 shoots per explant were generated on 3 mg l−1 of NAA followed by 3% of BP (7.0 shoots. Shoot elongation (1.52 cm was achieved on 1/2 MS medium fortified with NAA 7 mg l−1 followed by TDZ 7 mg l−1 (1.37 cm. Shoots cultured on 1/2 MS medium supplemented with IBA 5 mg l−1 produced an average of 8.75 roots per shoot, however the lengthiest roots (1.48 cm were noted in NAA 7 mg l−1. Healthy rooted plantlets successfully acclimatized in ex vitro condition. The role of complete plantlet production by natural additives could be useful for conservation and cost effective commercial production of orchids.

  1. Comparative study of in vitro regeneration efficiency of shoot-tip ...

    IRST Musanze


    Oct 24, 2011 ... observed on MS medium supplemented with 100 μM BAP while the quick buds development was observed on culture .... plants and the roots and leaves were removed. The explants were .... the reverse, the nodules which appeared on the explants ... grams below according to the average number of the.




    Full Text Available A study on propagation of three superior cassava ( Crant varieties i.e.Darul Hidayah, Malang-6 and Adira-4 through tissue culture technique was conducted at theTissue Culture Lab of SEAMEO BIOTROP, Bogor. The objective of the experiment was tostudy effect of plant growth regulators on propagation, which can be used in cassavamicropropagation protocol. Plant materials used were auxiliary shoots of a stem node. Theexperiment consisted of (i shoot multiplication, (ii roots induction, and (iii acclimatization.The multiple shoot regeneration was observed by using Murashige & Skoog (MS basal mediasupplemented with 0, 0.1, 1.0 and 5.0 mg/L of benzylaminopurine (BAP combined with 0.0,0.1 and 1.0 mg/L of thidiazuron. The root induction was observed by using 0.1 and 1.0 mg/Lof IBA and NAA. The resulting plantlets were transplanted into plastic polybags containingsoil mixed with organic fertilizer (1:1 covered with plastic sheets and transferred to agreenhouse. The result of the study showed that the highest number of shoots for DarulHidayah, Malang-6 and Adira-4 varieties were 4.93 shoots treated with BAP 1 mg/L +thidiazuron 0.1 mg/L, 4.20 shoots at BAP media of 1 mg/L, and 7.20 shoots at the mediaof BAP 1 mg/L + thidiazuron 0.1 mg/L respectively. The highest number of nodes producedwas 2.9 nodes for Darul Hidayah at BAP 5 mg/L, 5.13 nodes for Malang-6 at BAP 0.1 mg/L,and 6.18 nodes for Adira-4 at BAP 5 mg/L + thidiazuron 1 mg/L. The utilization of auxin IAAor NAA could induce and accelerate the growth of roots which finally could increase thesuccess of acclimatization process. With an average of four multiplication factors of eachculture period, the potency of each cassava shoot propagated through tissue culture couldproduce around 37 000 plants/year.

  3. Thidiazuron: A potent cytokinin for efficient plant regeneration in Himalayan poplar (Populus ciliata Wall. using leaf explants

    Gaurav Aggarwal


    Full Text Available Populus species are important resource for certain branches of industry and have special roles for scientific study on biological and agricultural systems. The present investigation was undertaken with an objective of enhancing the frequency of plant regeneration in Himalayan poplar (Populus ciliata Wall.. The effect of Thiadizuron (TDZ alone and in combination with adenine and α-Naphthalene acetic acid (NAA were studied on the regeneration potential of leaf explants. A high efficiency of shoot regeneration was observed in leaf (80.00% explants on MS basal medium supplemented with 0.024 mg/l TDZ and 79.7 mg/l adenine. Elongation and multiplication of shoots were obtained on Murashige and Skoog (MS basal medium, containing 0.5 mg/l 6. Benzyl aminopurine (BAP + 0.2mg/l Indole 3-acetic acid (IAA + 0.3 mg/l Gibberellic acid (GA3. High frequency root regeneration from in vitro developed shoots was observed on MS basal medium supplemented with 0.10 mg/l Indole 3-butyric acid(IBA. Maximum of the in vitro rooted plantlets were well accomplished to the mixture of sand: soil (1:1 and exhibited similar morphology with the field plants. A high efficiency plant regeneration protocol has been developedfrom leaf explants in Himalayan poplar (Populus ciliata Wall..

  4. Promotion of sink activity of developing rose shoots by light.

    Mor, Y; Halevy, A H


    Holding young rose shoots (Rosa hybrida cv. Marimba) in darkness while the rest of the plant was in light reduced the amount of (14)C assimilates recovered from the darkened shoot by half. Relative specific activity of the shoot tip grown in light was 13.5 times greater than that of the darkened one. The flower bud at the shoot tip degenerated in darkness and died. Shoots 2 to 3 centimeters long, after flower initiation, were most sensitive to the dark treatment. The degeneration is a gradual and reversible process in the first 8 days of darkness, followed by irreversible damage and atrophy. Darkening enhanced the ability of the young leaves to compete for the available assimilates over that of the darkened shoot tip. The enhancement of the mobilizing ability of the shoot tip by light is independent of photosynthesis since spraying with 3-(3,4-dichlorophenyl)-1,1-dimethylurea or holding shoots in a CO(2)-free atmosphere did not diminish the promoting effect of light on flower bud development or assimilate import. The possibility that light exerts its effect by photoproduction of ATP was also excluded inasmuch as no differences were found in ATP levels of shoot tips held in darkness and those held in light.

  5. In vitro mass propagation of Salvia canariensis by axillary shoots

    Sebastiana Mederos Molina


    Full Text Available During the establishment of shoots of Salvia canariensis L., five environmental factor treatments were applied. For each axillary node two shoots grew well when explants were incubated at continued ligth for 15 days followed by 16 hrs photoperiod by 30 days. Shoots multiplication was improved on a modified Murashige and Skoog (MS (1962 medium - MS + 825 mg/l NH4NO3 - supplemented with 10-7 M BA and 10-7 M NAA. The shoots produced well developed root systems within three weeks after transfer to the same culture medium supplemented with 5x 10-7 M NAA.

  6. Shoot Apical Meristem Organization in Several Philippine Species of Selaginella

    Prescillano Zamora


    Full Text Available This paper reports for the first time the occurrence of two types of shoot apical meristem organization on the main and lateral shoots of eight Philippine species of Selaginella: (1 shoot apical meristem with a single lenticular apical cell in S. cupressina and S. delicatula and (a shoot apical meristem with a row of several prominent prismatic apical cells in the lateral plane in S. jagorii, S. halconensis, S. involvens (S. polyura, S. peltata, S. flagellifera (S. biformis, S. nummularia, S. aristata, and S. philippina (endemic.

  7. Proliferative verrucous leukoplakia; a critical appraisal of the diagnostic criteria

    Carrard, V.C.; Brouns, E.R.E.A.; van der Waal, I.


    Since its introduction in the literature in 1985, the term proliferative verrucous leukoplakia (PVL) has been the subject of an ongoing discussion with regard to its definition. Widespread or multifocal occurrence of oral leukoplakia is not just synonymous to PVL. In the present treatise the proposa

  8. Dutch guidelines for diagnosis and therapy of proliferative lupus nephritis

    van Tellingen, A.; Voskuyl, A. E.; Vervloet, M. G.; Bijl, M.; de Sevaux, R. G. L.; Berger, S. P.; Derksen, R. H. W. M.; Berden, J. H. M.


    Proliferative lupus nephritis is a strong predictor of morbidity and mortality in patients with systemic lupus erythematosus. Despite improvements in the management of lupus nephritis, a significant number of the patients do not respond to immunosuppressive therapy and progress to end-stage renal fa

  9. Proliferative verrucous leukoplakia; a critical appraisal of the diagnostic criteria

    Carrard, V.C.; Brouns, E.R.E.A.; van der Waal, I.


    Since its introduction in the literature in 1985, the term proliferative verrucous leukoplakia (PVL) has been the subject of an ongoing discussion with regard to its definition. Widespread or multifocal occurrence of oral leukoplakia is not just synonymous to PVL. In the present treatise the

  10. Proliferative verrucous leukoplakia; a critical appraisal of the diagnostic criteria

    Carrard, V.C.; Brouns, E.R.E.A.; van der Waal, I.


    Since its introduction in the literature in 1985, the term proliferative verrucous leukoplakia (PVL) has been the subject of an ongoing discussion with regard to its definition. Widespread or multifocal occurrence of oral leukoplakia is not just synonymous to PVL. In the present treatise the proposa

  11. Muscle repair and regeneration: stem cells, scaffolds, and the contributions of skeletal muscle to amphibian limb regeneration.

    Milner, Derek J; Cameron, Jo Ann


    Skeletal muscle possesses a robust innate capability for repair of tissue damage. Natural repair of muscle damage is a stepwise process that requires the coordinated activity of a number of cell types, including infiltrating macrophages, resident myogenic and non-myogenic stem cells, and connective tissue fibroblasts. Despite the proficiency of this intrinsic repair capability, severe injuries that result in significant loss of muscle tissue overwhelm the innate repair process and require intervention if muscle function is to be restored. Recent advances in stem cell biology, regenerative medicine, and materials science have led to attempts at developing tissue engineering-based methods for repairing severe muscle defects. Muscle tissue also plays a role in the ability of tailed amphibians to regenerate amputated limbs through epimorphic regeneration. Muscle contributes adult stem cells to the amphibian regeneration blastema, but it can also contribute blastemal cells through the dedifferentiation of multinucleate myofibers into mononuclear precursors. This fascinating plasticity and its contributions to limb regeneration have prompted researchers to investigate the potential for mammalian muscle to undergo dedifferentiation. Several works have shown that mammalian myotubes can be fragmented into mononuclear cells and induced to re-enter the cell cycle, but mature myofibers are resistant to fragmentation. However, recent works suggest that there may be a path to inducing fragmentation of mature myofibers into proliferative multipotent cells with the potential for use in muscle tissue engineering and regenerative therapies.

  12. Perfluorodecalin and bone regeneration

    F Tamimi


    Full Text Available Perfluorodecalin (PFD is a chemically and biologically inert biomaterial and, as many perfluorocarbons, is also hydrophobic, radiopaque and has a high solute capacity for gases such as oxygen. In this article we have demonstrated, both in vitro and in vivo, that PFD may significantly enhance bone regeneration. Firstly, the potential benefit of PFD was demonstrated by prolonging the survival of bone marrow cells cultured in anaerobic conditions. These findings translated in vivo, where PFD incorporated into bone-marrow-loaded 3D-printed scaffolds substantially improved their capacity to regenerate bone. Secondly, in addition to biological applications, we have also shown that PFD improves the radiopacity of bone regeneration biomaterials, a key feature required for the visualisation of biomaterials during and after surgical implantation. Finally, we have shown how the extreme hydrophobicity of PFD enables the fabrication of highly cohesive self-setting injectable biomaterials for bone regeneration. In conclusion, perfluorocarbons would appear to be highly beneficial additives to a number of regenerative biomaterials, especially those for bone regeneration.

  13. Plant regeneration through callus organogenesis and true-to-type conformity of plants by RAPD analysis in Desmodium gangeticum (Linn.) DC.

    Cheruvathur, Meena K; Abraham, Jyothi; Thomas, T Dennis


    An efficient plant regeneration protocol was established for an endangered ethnomedicinal plant Desmodium gangeticum (Linn.) DC. Morphogenic calli were produced from 96 % of the cultures comprising the immature leaf explants on Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxyacetic acid (4.0 mg l(-1)) in combination with 6-benzylaminopurine (BA; 0.8 mg l(-1)). For callus regeneration, various concentrations of BA (1.0-5.0 mg l(-1)) or thidiazuron (TDZ; 1.0-5.0 mg l(-1)) alone or in combination with indole-3-acetic acid (IAA; 0.2-1.0 mg l(-1)) were used. Highest response of shoot regeneration was observed on MS medium fortified with TDZ (4.0 mg l(-1)) and IAA (0.5 mg l(-1)) combination. Here, 100 % cultures responded with an average number of 22.3 shoots per gram calli. Inclusion of indole-3-butyric acid in half MS medium favored rooting of recovered shoots. Out of 45 rooted plants transferred to soil, 40 survived. Total DNA was extracted from the leaves of the acclimatized plants of D. gangeticum. Analysis of random amplified polymorphic DNA using 13 arbitrary decanucleotide primers showed the genetic homogeneity in all the ten plants regenerated from callus with parental plant, suggesting that shoot regeneration from callus could be used for the true-to-type multiplication of this plant.

  14. Efficient and reproducible in vitro regeneration of Solanum lycopersicum and assessment genetic uniformity using flow cytometry and SPAR methods

    Abdulrahman A. Alatar


    Full Text Available In the present study, we develop an efficient and reproducible in vitro regeneration system for two cultivars viz., Jamila and Tomaland of Solanum lycopersicum L., an economically important vegetable crop throughout the world. Sterilization of seeds with 2.5% (v/v NaOCl was found to be most effective, about 97% of seeds germinated on cotton in magenta box moistened with sterile half strength (½Murashige and Skoog (MS medium. Regeneration efficiency of cotyledonary leaf (CL and cotyledonary node (CN explants derived from 08 days old aseptic seedling were assessed on MS medium supplemented with different concentrations of auxins and cytokinin. CL explants were found more responsive in comparison to CN in both the cultivars. Types of basal media were also assessed and found to have a significant effect on shoot regeneration. Highest regeneration frequency and maximum number of shoots were standardized from CL explants on MS medium supplied with 6-benzyl adenine (BA; 5.0 µM, indole-3-butyric acid (IBA; 2.5 µM and Kinetin (Kin; 10.0 µM. In vitro regenerated microshoots were rooted on ½MS medium containing 0.5 µM indole-3-butyric acid (IBA. Regenerated plantlets with well-developed roots and shoot system were successfully acclimated to ex vitro condition. Genetic uniformity of tissue culture raised plantlets was first time evaluated using flow cytometry and single primer amplification reaction (SPAR methods viz., DAMD and ISSR. No significant changes in ploidy level and nuclear DNA content profile were observed between in vitro propagated plants and normal plants of both the cultivars. Similarly, the SPAR analysis also revealed monomorphic banding patterns in regenerated plantlets of S. lycopersicum verifying their genetic uniformity and clonal fidelity. This efficient regeneration system can be used as a fast and reproducible method for genetic transformation of this important vegetable crop.

  15. Establishment and Optimization of the Regeneration System of Mature Embryos of Maize (Zea mays L.)

    ZHAO Cheng-hao; ZHANG Li-jun; GE Chao; HU Kai


    A reliable system was developed for regeneration from mature embryos derived from callus of four maize inbred lines (Liao 7980,Dan 9818,Dan 340,and Dan 5026).The protocol was mainly based on a series of experiments involving the composition of culture medium.We found that 9 μM 2,4-dichlorophenoxyacetic acid in MS medium was optimum for the induction of callus.The induction frequency of primary calli was over 85% for four inbred lines tested.The addition of L-proline (12 mM) in subculture medium significantly promoted the formation of embryogenic callus but it did not significantly enhance growth rate of callus.Efficient shoot regeneration was obtained on regeneration medium containing 2.22 μM 6-benzylaminopurine in combinations with 4.64 μM Kinetin.Regenerated shoots were rooted on half-strength MS medium containing 2.85 μM indole-3-butyric acid.This plant regeneration system provides a foundation for genetic transformation of maize.

  16. Levels and immunolocalization of endogenous cytokinins in thidiazuron-induced shoot organogenesis in carnation.

    Casanova, Eva; Valdés, Ana Elisa; Fernández, Belén; Moysset, Lluïsa; Trillas, Maria Isabel


    We evaluated the capacity of the plant growth regulator thidiazuron (TDZ), a substituted phenylurea with high cytokinin-like activity, to promote organogenesis in petals and leaves of several carnation cultivars (Dianthus spp.), combined with 1-naphthaleneacetic acid (NAA). The involvement of the endogenous auxin indole-3-acetic acid (IAA) and purine-type cytokinins was also studied. Shoot differentiation was found to depend on the explant, cultivar and balance of growth regulators. TDZ alone (0.5 and 5.0 micromol/L) as well as synergistically with NAA (0.5 and 5.0 micromol/L) promoted shoot organogenesis in petals, and was more active than N6-benzyladenine. In petals of the White Sim cultivar, TDZ induced cell proliferation in a concentration-dependent manner and, on day 7 of culture, the proportion of meristematic regions in those petals allowed the prediction of shoot regeneration capacity after 30 days of culture. Immunolocalization of CK ribosides, N6-(delta2-isopentenyl)adenosine, zeatin riboside (ZR) and dihydrozeatin riboside (DHZR), in organogenic petals showed them to be highly concentrated in the tips of bud primordia and in the regions with proliferation capacity. All of them may play a role in cell proliferation, and possibly in differentiation, during the organogenic process. After seven days of culture of White Sim petals, NAA may account for the changes found in the levels of IAA and DHZR, whereas TDZ may be responsible for the remarkable increases in N6-(delta2-isopentenyl)adenine (iP) and ZR. ZR is induced by low TDZ concentrations (0.0-0.005 micromol/L), whereas iP, that correlates with massive cell proliferation and the onset of shoot differentiation, is associated with high TDZ levels (0.5 micromol/L). In addition to the changes observed in quantification and in situ localization of endogenous phytohormones during TDZ-induced shoot organogenesis, we propose that TDZ also promotes growth directly, through its own biological activity. To our

  17. Effect of polyamines and silver nitrate on the high frequency regeneration from cotyledon explants of bottle gourd (Lagenaria siceraria; sp. asiatica).

    Shyamali, Saha; Hattori, Kazumi


    In this study, we have investigated the effect ofpolyamines (PA) and silver nitrate (AgNO3) on the high frequency regeneration from cotyledon explants of bottle gourd containing Murashige and Skoog (MS) media supplemented with different kind of Cytokinin alone or in the combination. Synergistic effect of kinetin (1 mg L(-1)) and benzyl adenine (BA) (2 mg L(-1)) itself showed highest shoot regeneration (80.6%) efficiency than BA or Kinetin alone in cotyledon explants of bottle gourd without adding AgNO3 or PAs. We have also observed that PAs and AgNO3 show their sensitivity on the regeneration, which is hormonal dependent. Regenerated shoots were rooted in half strength MS media containing 0.1 mg L(-1) IAA.

  18. Bioelectricity and epimorphic regeneration.

    Stewart, Scott; Rojas-Muñoz, Agustin; Izpisúa Belmonte, Juan Carlos


    All cells have electric potentials across their membranes, but is there really compelling evidence to think that such potentials are used as instructional cues in developmental biology? Numerous reports indicate that, in fact, steady, weak bioelectric fields are observed throughout biology and function during diverse biological processes, including development. Bioelectric fields, generated upon amputation, are also likely to play a key role during vertebrate regeneration by providing the instructive cues needed to direct migrating cells to form a wound epithelium, a structure unique to regenerating animals. However, mechanistic insight is still sorely lacking in the field. What are the genes required for bioelectric-dependent cell migration during regeneration? The power of genetics combined with the use of zebrafish offers the best opportunity for unbiased identification of the molecular players in bioelectricity.

  19. Transformation and regeneration of the holoparasitic plant Phelipanche aegyptiaca

    Fernández-Aparicio Mónica


    Full Text Available Abstract Background Transformation and subsequent regeneration of holoparasitic plants has never been reported, in part due to challenges in developing transformation protocols, but also because regeneration of obligate parasites is difficult since their survival depends completely on successful haustorium penetration of a host and the formation of vascular connections. The recent completion of a massive transcriptome sequencing project (the Parasitic Plant Genome Project will fuel the use of genomic tools for studies on parasitic plants. A reliable system for holoparasite transformation is needed to realize the full value of this resource for reverse genetics and functional genomics studies. Results Here we demonstrate that transformation of Phelipanche aegyptiaca is achieved by infection of 3 month-old in vitro grown P. aegyptiaca calli with Agrobacterium rhizogenes harboring the yellow fluorescent protein (YFP. Four months later, YFP-positive regenerated calli were inoculated onto tomato plants growing in a minirhizotron system. Eight days after inoculation, transgenic parasite tissue formed lateral haustoria that penetrated the host and could be visualized under UV illumination through intact host root tissue. YFP-positive shoot buds were observed one month after inoculation. Conclusions This work constitutes a breakthrough in holoparasitic plant research methods. The method described here is a robust system for transformation and regeneration of a holoparasitic plant and will facilitate research on unique parasitic plant capabilities such as host plant recognition, haustorial formation, penetration and vascular connection.

  20. Cell kinetics during regeneration in the sponge Halisarca caerulea: how local is the response to tissue damage?

    Brittany E. Alexander


    Full Text Available Sponges have a remarkable capacity to rapidly regenerate in response to wound infliction. In addition, sponges rapidly renew their filter systems (choanocytes to maintain a healthy population of cells. This study describes the cell kinetics of choanocytes in the encrusting reef sponge Halisarca caerulea during early regeneration (0–8 h following experimental wound infliction. Subsequently, we investigated the spatial relationship between regeneration and cell proliferation over a six-day period directly adjacent to the wound, 1 cm, and 3 cm from the wound. Cell proliferation was determined by the incorporation of 5-bromo-2′-deoxyuridine (BrdU. We demonstrate that during early regeneration, the growth fraction of the choanocytes (i.e., the percentage of proliferative cells adjacent to the wound is reduced (7.0 ± 2.5% compared to steady-state, undamaged tissue (46.6 ± 2.6%, while the length of the cell cycle remained short (5.6 ± 3.4 h. The percentage of proliferative choanocytes increased over time in all areas and after six days of regeneration choanocyte proliferation rates were comparable to steady-state tissue. Tissue areas farther from the wound had higher rates of choanocyte proliferation than areas closer to the wound, indicating that more resources are demanded from tissue in the immediate vicinity of the wound. There was no difference in the number of proliferative mesohyl cells in regenerative sponges compared to steady-state sponges. Our data suggest that the production of collagen-rich wound tissue is a key process in tissue regeneration for H. caerulea, and helps to rapidly occupy the bare substratum exposed by the wound. Regeneration and choanocyte renewal are competing and negatively correlated life-history traits, both essential to the survival of sponges. The efficient allocation of limited resources to these life-history traits has enabled the ecological success and diversification of sponges.

  1. An analysis of the growth of the retinal cell population in embryonic chicks yielding proliferative ratios, numbers of proliferative and non-proliferative cells and cell-cycle times for successive generations of cell cycles.

    Morris, V B; Cowan, R


    Growth curves of the retinal cell population of embryonic chicks were fitted by a branching-process model of cell population growth, thereby estimating the proliferative ratios and mean cell-cycle times of the generations of cell cycles that underlie retinal growth. The proliferative ratio determines the proportion of cells that divides in the next generation, so the numbers of proliferative and non-proliferative cells in each generation of cell cycles were obtained. The mean cell-cycle times determine the times over which the generations are extant. Assuming growth starts from one cell in generation 0, the proliferative cells reach 3.6 x 10(6) and the non-proliferative cells reach 1.1 x 10(6) by generation 23. The next four generations increase the proliferative cell numbers to 13.9 x 10(6) and produce 20.1 x 10(6) non-proliferative cells. In the next five generations in the end phase of growth, non-proliferative cells are produced in large numbers at an average of 13.9 x 10(6) cells per generation as the retinal lineages are completed. The retinal cell population reaches a maximum estimated here at 98.2 x 10(6) cells. The mean cell-cycle time estimates range between 6.8 and 10.1 h in generations before the end phase of growth and between 10.6 and 17.2 h in generations in the end phase. The retinal cell population growth is limited by the depletion of the proliferative cell population that the production of non-proliferative cells entails. The proliferative ratios and the cell-cycle-time distribution parameters are the likely determinants of retinal growth rates. The results are discussed in relation to other results of spatial and temporal patterns of the cessation of cell cycling in the embryonic chick retina.

  2. [Regeneration of airway epithelium].

    Adam, D; Perotin, J-M; Lebargy, F; Birembaut, P; Deslée, G; Coraux, C


    Epithelial regeneration is a complex process. It can lead to the remodeling of the airway epithelium as in asthma, COPD or cystic fibrosis. The development of in vivo and in vitro models has allowed the analysis of remodeling mechanisms and showed the role of components of extracellular matrix, proteases, cytokines and growth factors. Airway epithelial progenitors and stems cells have been studied in these models. However, their identification remains difficult. Identification and characterization of airway epithelial progenitor/stem-cells, and a better knowledge of the regeneration process may allow the development of new therapeutic strategies for airway epithelial reconstitution. Copyright © 2013 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  3. Shoot Differentiation in Callus Cultures of Datura Innoxia

    Engvild, Kjeld Christensen


    promoted shoot differentiation. Gibberellic acid inhibited shoot formation weakly, but inhibited proper leaf blade formation. Root differentiation was rare. The callus cultures of Datura innoxia grew rapidly (100-fold in 4 weeks) on a slightly modified Murashige and Skoog medium (0.5 mg/l thiamin · HCl, p...

  4. Role of endodermal cell vacuoles in shoot gravitropism.

    Kato, Takehide; Morita, Miyo Terao; Tasaka, Masao


    In higher plants, shoots and roots show negative and positive gravitropism, respectively. Data from surgical ablation experiments and analysis of starch deficient mutants have led to the suggestion that columella cells in the root cap function as gravity perception cells. On the other hand, endodermal cells are believed to be the statocytes (that is, gravity perceiving cells) of shoots. Statocytes in shoots and roots commonly contain amyloplasts which sediment under gravity. Through genetic research with Arabidopsis shoot gravitropism mutants, sgr1/scr and sgr7/shr, it was determined that endodermal cells are essential for shoot gravitropism. Moreover, some starch biosynthesis genes and EAL1 are important for the formation and maturation of amyloplasts in shoot endodermis. Thus, amyloplasts in the shoot endodermis would function as statoliths, just as in roots. The study of the sgr2 and zig/sgr4 mutants provides new insights into the early steps of shoot gravitropism, which still remains unclear. SGR2 and ZIG/SGR4 genes encode a phospholipase-like and a v-SNARE protein, respectively. Moreover, these genes are involved in vacuolar formation or function. Thus, the vacuole must play an important role in amyloplast sedimentation because the sgr2 and zig/sgr4 mutants display abnormal amyloplast sedimentation.

  5. Determinants of elite-level air rifle shooting performance.

    Ihalainen, S; Kuitunen, S; Mononen, K; Linnamo, V


    This study focused on identifying the most important factors determining performance in elite-level air rifle shooting technique. Forty international- and national-level shooters completed a simulated air rifle shooting competition series. From a total of 13 795 shots in 319 tests, shooting score and 17 aiming point trajectory variables were measured with an optoelectronic device and six postural balance variables were measured with force platform. Principal component analysis revealed six components in the air rifle shooting technique: aiming time, stability of hold, measurement time, cleanness of triggering, aiming accuracy, and timing of triggering. Multiple regression analysis identified four of those, namely stability of hold, cleanness of triggering, aiming accuracy, and timing of triggering as the most important predictors of shooting performance, accounting for 81% of the variance in shooting score. The direct effect of postural balance on performance was small, accounting for less than 1% of the variance in shooting score. Indirectly, the effect can be greater through a more stable holding ability, to which postural balance was correlated significantly (R = 0.55, P < 0.001). The results of the present study can be used in assessing athletes' technical strengths and weaknesses and in directing training programs on distinct shooting technical components. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. In Vitro Shoot Bud Differentiation from Hypocotyl Explants of Chili Peppers (Capsicum annuum L.



    Full Text Available Chili pepper (Capsicum annuum L. is an economically important spice crop in tropical and subtropical countries. In vitro plant regeneration was obtained from 15th day old hypocotyl explants of three chili pepper cultivars (Capsicum annuum L., var. �X-235�, var. �PC-1� and var. �Pusa Jwala�. Among the genotypes of Capsicum L. var. �X-235� responded better than the var. �PC-1� and var. �Pusa Jwala�. MS medium containing BAP (4.0 mg/l and IAA (0.5 mg/l was found to be the best medium for the production of maximum number of shoot buds in all the genotypes of chili pepper i.e., 6.80�0.16 (var. �X-235�, 5.00�0.19 (var. �PC-1� and 4.80�0.12 (var. �Pusa Jwala�. The shoots were rooted on MS medium fortified with IBA (0.5 mg/l. Rooted plants were hardened and transplanted to the soil. The plants showed 80-90% survival during transplantation.

  7. In Vitro Shoot Bud Differentiation from Hypocotyl Explants of Chili Peppers (Capsicum annuum L.



    Full Text Available Chili pepper (Capsicum annuum L. is an economically important spice crop in tropical and subtropical countries. In vitro plant regeneration was obtained from 15th day old hypocotyl explants of three chili pepper cultivars (Capsicum annuum L., var. X-235, var. PC-1 and var. Pusa Jwala. Among the genotypes of Capsicum L. var. X-235 responded better than the var. PC-1 and var. Pusa Jwala. MS medium containing BAP (4.0 mg/l and IAA (0.5 mg/l was found to be the best medium for the production of maximum number of shoot buds in all the genotypes of chili pepper i.e., 6.800.16 (var. X-235, 5.000.19 (var. PC-1 and 4.800.12 (var. Pusa Jwala. The shoots were rooted on MS medium fortified with IBA (0.5 mg/l. Rooted plants were hardened and transplanted to the soil. The plants showed 80-90% survival during transplantation.

  8. Efficient plant regeneration of bittersweet (Solanum dulcamara L., a medicinal plant

    Arzu Ucar Turker


    Full Text Available Solanum dulcamara L. (bittersweet is a medicinal plant that has been used to treat skin diseases, warts, tumors, felons, arthritis, rheumatism, bronchial congestion, heart ailments, ulcerative colitis, eye inflammations, jaundice and pneumonia. A reliable in vitro culture protocol for bittersweet was established. Explants (leaf and petiole segments were cultured on Murashige and Skoog minimal organics (MSMO medium with various plant growth regulator combinations. Leaf explants formed more shoots than petiole explants. Plant regeneration was observed through indirect organogenesis with both explants. Best shoot proliferation was obtained from leaf explants with 3 mg/l BA (benzyladenine and 0.5 mg/l IAA (indole-3-acetic acid. Regenerated shoots were transferred to rooting media containing different levels of IAA (indole-3-acetic acid, IBA (indole-3-butyric acid, NAA (naphthalene acetic acid or 2,4-D (2,4 dichlorophenoxyacetic acid. Most shoots developed roots on medium with 0.5 mg/l IBA. Rooted explants were transferred to vermiculate in Magenta containers for acclimatization and after 2 weeks, they were planted in plastic pots containing potting soil and maintained in the plant growth room.

  9. In vitro high frequency regeneration of plantlets of Vigna mungo and their ex vitro growth.

    Agnihotri, S; Singh, R R; Chaturvedi, H C


    Of the five explants of V. mungo var. T9 used, the excised shoot tips gave best response with regard to offshoot formation followed by the embryonal axis explants. While a treatment comprising 0.5 mgL(-1) BAP, 0.5 mgL(-1) 2iP and 0.1 mgL(-1) NAA induced differentiation of an average 10 offshoots in shoot tip explants, only 3 offshoots were formed in the explants of embryonal axis in a treatment containing 0.5 mgL(-1) BAP and 0.1 mgL(-1) NAA, found optimum for them. Multiple shoots differentiated when explants with earlier regenerated and growing offshoots were first cultured in a treatment containing 0.1 mgL(-1) BAP, 0.25 mgL(-1) IAA and 5 mgL(-1) CCC and then subcultured in the same treatment but having only 1 mgL(-1) CCC. The isolated shoots rooted in 0.5 mgL(-1) IAA resulted in the formation of complete plantlets of an average height of 15 cm in 20 days. The in vitro-regenerated plants grew normally under field conditions and came to flowering as well.


    Loeb, J


    1. Equal masses of sister leaves of Bryophyllum calycinum produce equal masses of shoots and roots in equal time and under equal conditions. 2. The mass of shoots and roots produced by different masses of sister leaves in equal time and under equal conditions is approximately in direct proportion to the masses of the leaves. 3. When a piece of stem inhibits the production of shoots and roots in a leaf of Bryophyllum connected with it, the stem gains in mass and this gain in mass equals approximately the mass of shoots and roots the leaf would have produced if it had been detached from the stem. 4. This suggests that the inhibitory influence of the stem upon the formation of shoots and roots in the leaf is due to the fact that the material available for this process naturally flows into the stem.

  11. Mental illness, mass shootings, and the politics of American firearms.

    Metzl, Jonathan M; MacLeish, Kenneth T


    Four assumptions frequently arise in the aftermath of mass shootings in the United States: (1) that mental illness causes gun violence, (2) that psychiatric diagnosis can predict gun crime, (3) that shootings represent the deranged acts of mentally ill loners, and (4) that gun control "won't prevent" another Newtown (Connecticut school mass shooting). Each of these statements is certainly true in particular instances. Yet, as we show, notions of mental illness that emerge in relation to mass shootings frequently reflect larger cultural stereotypes and anxieties about matters such as race/ethnicity, social class, and politics. These issues become obscured when mass shootings come to stand in for all gun crime, and when "mentally ill" ceases to be a medical designation and becomes a sign of violent threat.

  12. Proliferative periostitis of the mandibular ramus and condyle: a case report

    Seok, Hyun; Kim, Seong-Gon; Song, Ji-Young


    Proliferative periostitis is a rare form of osteomyelitis that is characterized by new bone formation with periosteal reaction common causes of proliferative periostitis are dental caries, periodontitis, cysts, and trauma. While proliferative periostitis typically presents as a localized lesion, in this study, we describe an extensive form of proliferative periostitis involving the whole mandibular ramus and condyle. Because the radiographic findings were similar to osteogenic sarcoma, an acc...

  13. Proliferative periostitis of the mandibular ramus and condyle: a case report.

    Seok, Hyun; Kim, Seong-Gon; Song, Ji-Young


    Proliferative periostitis is a rare form of osteomyelitis that is characterized by new bone formation with periosteal reaction common causes of proliferative periostitis are dental caries, periodontitis, cysts, and trauma. While proliferative periostitis typically presents as a localized lesion, in this study, we describe an extensive form of proliferative periostitis involving the whole mandibular ramus and condyle. Because the radiographic findings were similar to osteogenic sarcoma, an accurate differential diagnosis was important for proper treatment.

  14. Direct Adventitious Bud Induction and Plant Regeneration of Rosa hybrida Samantha

    GAO Li-ping; BAO Man-zhu


    Effect of explant, site of leaflet, induction period in the dark and combinations of plant growth regulators on direct adventitious bud induction and plant regeneration of Rosa hybrida Samantha was investigated. The results showed that after an induction period of 8 d on MS medium with 1.5 mg L-1 TDZ and 0.05 mg L-1 NAA in the dark and a subculture on MS medium with 0.5 mg L-1 BA and 0.01 mg L-1 NAA under light, the best plant regeneration was obtained and the regeneration frequencies of leaflets and petioles were 51.8 and 10% respectively. There was no significant difference in regeneration ability between leaflets at different sites of the compound leaves, longer time of induction in the dark or high concentration of auxin would cause callus formation, which was disadvantageous for shoot regeneration, and the regeneration frequency was significantly reduced. This regeneration system could be applied for genetic transformation of this cultivar in the future.

  15. An improved plant regeneration and Agrobacterium - mediated transformation of red pepper (Capsicum annuum L.).

    Kumar, R Vinoth; Sharma, V K; Chattopadhyay, B; Chakraborty, S


    Capsicum annuum (red pepper) is an important spice cum vegetable crop in tropical and subtropical countries. Here, we report an effective and reproducible auxin free regeneration method for six different red pepper cultivars (ACA-10, Kashi Anmol, LCA-235, PBC-535, Pusa Jwala and Supper) using hypocotyl explants and an efficient Agrobacterium-mediated transformation protocol. The explants (hypocotyls, cotyledonary leaves and leaf discs) collected from axenic seedlings of six red pepper cultivars were cultured on either hormone free MS medium or MS medium supplemented with BAP alone or in combination with IAA. Inclusion of IAA in the regeneration medium resulted in callus formation at the cut ends of explants, formation of rosette leaves and ill defined shoot buds. Regeneration of shoot buds could be achieved from hypocotyls grown in MS medium supplemented with different concentrations of BAP unlike other explants which failed to respond. Incorporation of GA3 in shoot elongation medium at 0.5 mg/l concentration enhanced the elongation in two cultivars, LCA-235 and Supper, while other cultivars showed no significant response. Chilli cultivar, Pusa Jwala was transformed with βC1 ORF of satellite DNA β molecule associated with Chilli leaf curl Joydebpur virus through Agrobacterium tumefaciens. Transgene integration in putative transformants was confirmed by PCR and Southern hybridization analysis.

  16. Infection and Pulp Regeneration

    Sahng G. Kim


    Full Text Available The regeneration of the pulp-dentin complex has been a great challenge to both scientists and clinicians. Previous work has shown that the presence of prior infection may influence the characteristics of tissues formed in the root canal space after regenerative endodontic treatment. The formation of ectopic tissues such as periodontal ligament, bone, and cementum has been observed in the root canal space of immature necrotic teeth with apical periodontitis, while the regeneration of dentin and pulp has been identified in previously non-infected teeth. The current regenerative endodontic therapy utilizes disinfection protocols, which heavily rely on chemical irrigation using conventional disinfectants. From a microbiological point of view, the current protocols may not allow a sufficiently clean root canal microenvironment, which is critical for dentin and pulp regeneration. In this article, the significance of root canal disinfection in regenerating the pulp-dentin complex, the limitations of the current regenerative endodontic disinfection protocols, and advanced disinfection techniques designed to reduce the microorganisms and biofilms in chronic infection are discussed.

  17. Simplified Regeneration Protocol for Cycas revoluta Thunb. Mature Zygotic Embryos

    Rohangiz NADERI


    Full Text Available Mature zygotic embryos of Cycas revoluta Thunb. were used as explants to investigate direct and indirect organogenesis. Explants were incubated on half-strength Murashige and Skoog (½ MS basal medium supplemented with various plant growth regulators, singly or in combination (all at 0.5 mg l-1: 6-benzyladenine (BA, kinetin (Kin, 2,4-dichlorophenoxyacetic acid (2,4-D, Kin×2,4-D, BA×Kin and BA×2,4-D. Cultures were placed at a low light intensity (4 µmol m-2 s-1 PPFD. Adventitious shoot regeneration was observed in the presence of 0.5 mg l-1BA after 35 days. The highest number of direct and indirect shoots per zygotic embryo was 3.67 and 29.67, respectively. Roots were induced on indirect shoots by continuous culture on rooting medium (½ MS,‏ 0.1 mg l-1 1-naphthaleneacetic acid and hardened successfully in perlite. Each rooted plantlet with pinnate leaves and a primary tap root was individually isolated and acclimatized 185 days after the beginning of culture, with a 10% success rate.

  18. First Reported Case of Proliferative Retinopathy in Hemoglobin SE Disease

    Paul Baciu


    Full Text Available We report the first case of proliferative sickle cell retinopathy in a patient with hemoglobin SE (Hb SE disease. Only a few dozen cases of Hb SE disease have been reported previously, and none had evidence of proliferative retinopathy. A 56-year-old African American man presented to our clinic for routine examination and was found to have sea-fan peripheral neovascularization bilaterally without maculopathy. Hemoglobin analysis revealed Hb SE heterozygosity. Sector laser photocoagulation to areas of nonperfusion in both eyes resulted in regression of the peripheral neovascularization over a period of 6 months. Although Hb SE disease is rare, the incidence of Hb SE disease is postulated to rise in the future. Awareness of its potential ocular complications is needed to appropriately refer these patients for screening.

  19. Stimulating endogenous cardiac regeneration

    Amanda eFinan


    Full Text Available The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration,a combination of these approaches couldameliorate the overall repair process to incorporate the participation ofmultiple cell players.

  20. Proliferative verrucous leukoplakia may initially mimic lichenoid reactions.

    Lopes, Marcio Ajudarte; Feio, Patricia; Santos-Silva, Alan Roger; Vargas, Pablo Agustin


    Proliferative verrucous leukoplakia is an intriguing disease, which occurs particularly in women aged greater than 60 years, is not associated with tobacco and alcohol, and has a high risk of recurrence and malignant transformation. Although it is well known that the typical presentation is characterized by multifocal and verrucous white lesions, there is no description that its initial clinical presentation may simulate a lichenoid reaction.

  1. Limb regeneration: a new development?

    Nacu, Eugen; Tanaka, Elly M


    Salamander limb regeneration is a classical model of tissue morphogenesis and patterning. Through recent advances in cell labeling and molecular analysis, a more precise, mechanistic understanding of this process has started to emerge. Long-standing questions include to what extent limb regeneration recapitulates the events observed in mammalian limb development and to what extent are adult- or salamander- specific aspects deployed. Historically, researchers studying limb development and limb regeneration have proposed different models of pattern formation. Here we discuss recent data on limb regeneration and limb development to argue that although patterning mechanisms are likely to be similar, cell plasticity and signaling from nerves play regeneration-specific roles.

  2. Proliferative Effects of Histamine on Primary Human Pterygium Fibroblasts

    Zhenwei Qin


    Full Text Available Purpose. It has been confirmed that inflammatory cytokines are involved in the progression of pterygium. Histamine can enhance proliferation and migration of many cells. Therefore, we intend to investigate the proliferative and migratory effects of histamine on primary culture of human pterygium fibroblasts (HPFs. Methods. Pterygium and conjunctiva samples were obtained from surgery, and toluidine blue staining was used to identify mast cells. 3-[4, 5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT was performed to evaluate the proliferative rate of HPFs and human conjunctival fibroblasts (HCFs; ki67 expression was also measured by immunofluorescence analysis. Histamine receptor-1 (H1R antagonist (Diphenhydramine Hydrochloride and histamine receptor-2 (H2R antagonist (Nizatidine were added to figure out which receptor was involved. Wound healing model was used to evaluate the migratory ability of HPFs. Results. The numbers of total mast cells and degranulated mast cells were both higher in pterygium than in conjunctiva. Histamine had a proliferative effect on both HPFs and HCFs, the effective concentration (10 μmol/L on HPFs was lower than on HCFs (100 μmol/L, and the effect could be blocked by H1R antagonist. Histamine showed no migratory effect on HPFs. Conclusion. Histamine may play an important role in the proliferation of HPFs and act through H1R.

  3. Laminins Expression in Children with Mesangial Proliferative Glomerulonephritis

    赵非; 黄松明; 陈荣华; 费莉; 郭梅; 黄文彦


    Objective: To investigate the role of laminins in the pathogensis of mesangial praliferalive glomeruonephritis (MsPGN ) in children. Methods: Eighteen renal biopsy specimens of MsPGN and 6 normal kidneys were studied by means of immunohistochemistry and in situ hybridization.Results: ① Protein of α1 chain and γ1 chain of laminin increased around the segments of proliferative mesangium. Increased expression of α2 and βl proteins was found in the segments with mesangial proliferation whereas the β2 chain expression decreased in these areas. ② The mRNA expression of αl,α2,β1 and γ1 increased to different degrees in glomeeruli with mesangial proliferation. But no difference was detected among Mild, Moderate, and Severe MsPGN. Conclusion:①The quantitative and qualitative alterations of laminin chains’ distribution were found in the measngial proliferative glomeruli. The proliferative mesougial cells were the origins of abnormal accumulation and expression of laminins.③ These changes may be the basis of the progresses of MsPGN.

  4. Production of yam mosaic virus (ymv)-free Dioscorea opposita plants by cryotherapy of shoot-tips.

    Shin, Jong Hee; Kang, Dong Kyoon; Sohn, Jae Keun


    In the present study, Yam mosaic virus (YMV) could be efficiently eliminated by cryotherapy in Dioscorea opposita. Shoot apices were precultured for 16 h with 0.3 M sucrose, encapsulated in sodium alginate and dehydrated for 4 h prior to direct immersion in liquid nitrogen. Up to 90 percent of the plants regenerated from cryopreserved shoot tips were YMV-free, whereas only 40% of those regenerated using meristem culture were YMV-free. YMV-free yam plantlets could be propagated in vitro through nodal stem culture, with sequential subculturing at 6-week intervals on medium containing 0.5 mg per liter kinetin. The microtubers formed at the bottom and axil of the explants, incubated at 30 degreeC after being chilled (4 degree C) for 3 months, could be sprouted successfully under in vivo conditions. Healthy plants were established without any damaging symptoms of the virus. Thus, cryotherapy provides an alternative method for efficient elimination of yam viruses, and could be simultaneously used for long-term storage of yam germplasm and for the production of virus-free plants.

  5. Planar cell polarity-mediated induction of neural stem cell expansion during axolotl spinal cord regeneration.

    Rodrigo Albors, Aida; Tazaki, Akira; Rost, Fabian; Nowoshilow, Sergej; Chara, Osvaldo; Tanaka, Elly M


    Axolotls are uniquely able to mobilize neural stem cells to regenerate all missing regions of the spinal cord. How a neural stem cell under homeostasis converts after injury to a highly regenerative cell remains unknown. Here, we show that during regeneration, axolotl neural stem cells repress neurogenic genes and reactivate a transcriptional program similar to embryonic neuroepithelial cells. This dedifferentiation includes the acquisition of rapid cell cycles, the switch from neurogenic to proliferative divisions, and the re-expression of planar cell polarity (PCP) pathway components. We show that PCP induction is essential to reorient mitotic spindles along the anterior-posterior axis of elongation, and orthogonal to the cell apical-basal axis. Disruption of this property results in premature neurogenesis and halts regeneration. Our findings reveal a key role for PCP in coordinating the morphogenesis of spinal cord outgrowth with the switch from a homeostatic to a regenerative stem cell that restores missing tissue.

  6. Metabolic changes associated with shoot formation in tobacco callus cultures

    Grady, K.L.


    Callus tissue derived from Nicotiana tabacum L. stem pith parenchyma cells was grown either on medium which maintains the callus in an undifferentiated state, or on medium which induces the formation of shoots. Two complementary types of studies were performed with the goal of establishing metabolic markers for the initiation of shoot formation: one designed to characterize the flow of radioactive sucrose into various metabolic pools, and one which allowed measurement of intermediary metabolite concentrations. In the former, callus tissue was incubated in (U-/sup 14/C)sucrose for periods up to one hour, and patterns of metabolite labelling in tissue grown on shoot-forming and non-shoot-forming media were compared. In the latter studies, tissue was grown for an entire subculture period on non-shoot-forming medium labelled with (U-/sup 14/C)sucrose, then subcultured to labelled non-shoot-forming or shoot-forming media, and sampled at intervals during the first week of growth. 189 references.

  7. Micropropagation of Paulownia fortuneii through in vitro axillary shoot proliferation.

    Venkateswarlu, B; Mukhopadhyay, J; Sreenivasan, E; Kumar, V M


    Primary cultures were established with nodal segments from juvenile shoots of two- year-old Paulownia fortuneii trees from a clonal plantation in Andhra Pradesh. A medium containing half-strength MS salts + RAP (1 mg/L) + sucrose (2%) produced optimum bud break in nodal explants. The same basal medium with reduced hormone level (0.5 mg/L) supported maximum multiplication of secondary cultures of P. fortuneii (1:6 in 6 weeks). Specific treatments were tested to enhance this rate of multiplication. In one approach, five to six week old in vitro grown shoots were ratooned (cutting the main shoot at the bottom leaving one node). The stumps (ratooned basal node) produced 2 to 3 axillary shoots, which grew into 4 to 5 nodes by 3 weeks; thus, providing additional shoots from the same explant. This provided 30% additional shoots in 4 cycles. Secondly, reducing the light intensity to 1200 lux resulted in higher shoot elongation, i.e, formation of 8 nodes in 5 weeks with healthier shoots than the normal intensity of 3000 lux under which only 6 nodes were produced in 6 weeks. In vitro-grown shoots could be successfully rooted ex vitro in vermiculite + cocopeat mixture (1:1 v/v) under 90% humidity, transferred to soil in polybags for hardening in the green house for 2 weeks and shifted to shade net for further hardening. After one month, the plants could be successfully transplanted to field with 95% survival. Micropropagated plants showed an excellent growth in the field attaining a height of 1.5 m and a collar diameter of 2.8 cm in 3 months.

  8. Auxin at the Shoot Apical Meristem

    Vernoux, Teva; Besnard, Fabrice; Traas, Jan


    Plants continuously generate new tissues and organs through the activity of populations of undifferentiated stem cells, called meristems. Here, we discuss the so-called shoot apical meristem (SAM), which generates all the aerial parts of the plant. It has been known for many years that auxin plays a central role in the functioning of this meristem. Auxin is not homogeneously distributed at the SAM and it is thought that this distribution is interpreted in terms of differential gene expression and patterned growth. In this context, auxin transporters of the PIN and AUX families, creating auxin maxima and minima, are crucial regulators. However, auxin transport is not the only factor involved. Auxin biosynthesis genes also show specific, patterned activities, and local auxin synthesis appears to be essential for meristem function as well. In addition, auxin perception and signal transduction defining the competence of cells to react to auxin, add further complexity to the issue. To unravel this intricate signaling network at the SAM, systems biology approaches, involving not only molecular genetics but also live imaging and computational modeling, have become increasingly important. PMID:20452945

  9. In vitro regeneration from petiole explants of non-toxic Jatropha curcas

    Kumar, Nitish


    Jatropha curcas, a multipurpose shrub has acquired significant economic potential as biodiesel plant. The seeds or pressed cake is toxic due to the presence of toxic substances and is not useful as food/fodder despite having the best protein composition. A simple, efficient, and reproducible method for plant regeneration through direct organogenesis from petiole explants of non-toxic J. curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ). The best induction of shoot buds (57.61%), and number of shoot buds (4.98) per explant were obtained when in vitro petiole explants were placed horizontally on MS medium supplemented with 2.27 mu M TDZ. The Induced shoot buds were transferred to MS medium containing 10 mu M kinetin (Kn), 4.5 mu M 6-benzyl aminopurine (BA), and 5.5 mu M alpha-naphthaleneacetic acid (NAA) for shoot proliferation and subsequent elongation was achieved on MS medium supplemented with 2.25 mu M BA and 8.5 mu M IAA. The elongated shoots could be rooted on half-strength MS medium with 15 mu M IBA, 11.4 mu M IAA and 5.5 mu M NAA with more than 90% survival rate. (C) 2010 Elsevier B.V. All rights reserved.

  10. Mutants in Arabidopsis thaliana with altered shoot gravitropism

    Bullen, B.L.; Poff, K.L.


    A procedure has been developed and used to screen 40,000 m-2 seedlings of Arabidopsis thaliana for strains with altered shoot gravitropism. Several strains have been identified for which shoot gravitropism is considerably more random than that of their wild-type parent (based on frequency distribution histograms of the gravitropic response to a 1 g stimulus). One such strain exhibits normal hypocotyl phototropism and normal root gravitropism. Thus, the gravitropism pathway in the shoot contains at least one mutable element which is not required for root gravitropism.

  11. The role of peripheral nerves in urodele limb regeneration.

    Stocum, David L


    Nerve axons and the apical epidermal cap (AEC) are both essential for the formation of an accumulation blastema by amputated limbs of urodele salamanders. The AEC forms in the absence of axons, but is not maintained, and blastema formation fails. Growth stages of the blastema become nerve-independent for morphogenesis, but remain dependent on the nerve for blastema growth. Denervated growth stage blastemas form smaller than normal skeletal parts, owing to diminished mitosis, but form the full proximodistal array of skeletal elements. This difference in nerve dependency of morphogenesis and proliferation is hypothesized to be the result of a dependence of the AEC on nerves for blastema cell proliferation but not for blastema morphogenesis. Regenerating axons induce the synthesis and secretion of the anterior gradient protein (AGP) by distal Schwann cells during dedifferentiation and by the gland cells of the AEC during blastema growth stages. AGP promotes the regeneration of a denervated limb to digit stages when electroporated into the limb during dedifferentiation. Once a critical mass of blastema cells has been attained, the blastema can undergo morphogenesis in the absence of the nerve, but the regenerate will be a miniature, because the nerve is no longer inducing the AEC to carry out its AGP-mediated proliferative function. AGP expression by both Schwann cells and the AEC is induced by axons, but the nature of the inductive agent is unclear.

  12. High Frequency Plant Regeneration of Musa paradisiaca cv. Karibale Monthan

    R. Shashi Kumar


    Full Text Available High frequency plant regeneration protocol has been standardized from banana cultivar Musa paradisiaca cv. Karibale Monthan, an endemic cultivar of Malnad region of Karnataka. The fruits are used as glomerular protective to solve kidney problems. To minimize the microbial contamination and to promote healthy growth, explants were treated with 70 % absolute alcohol for 6 min, 0.1 % Mercuric chloride for 10 min and 0.2 % for 10 min, 1 % Sodium hypochlorite for 15 min, 0.1 % Cefotaxime for 5 min and 0.05 % Gentamicin for 5 min. The high frequency shoot initiation (93.33 % was recorded at 5 mg/l BAP. The synergetic effect of BAP (4 to 6 mg/l, TDZ (0.1 to 1.2 mg/l and coconut water (0.1 to 0.9 ml/l induced multiple shoot buds and it was optimized at the concentration of 5 mg/l BAP, 0.5 mg/l TDZ and 0.5 ml/l coconut water with 15.90 ± 1.66 frequency of shoots per propagule. Supplementation of 1.0 mg/l IBA induced 5.33 ± 1.21 numbers of roots with a mean root length of 7.50 ± 1.87 roots. The 99% of plantlets with distinct roots and shoots were successfully acclimatized in the green house and transferred to the field to evaluate the agro-morphological variations. The weight of the bunch (kg, number of hands in a bunch, number of fingers in a hand, length of the finger (cm, girth of the finger (cm and girth of the pseudostem (cm exhibited by in vitro plants were higher than the in vivo plants.

  13. A dual epimorphic and compensatory mode of heart regeneration in zebrafish.

    Sallin, Pauline; de Preux Charles, Anne-Sophie; Duruz, Vincent; Pfefferli, Catherine; Jaźwińska, Anna


    Zebrafish heart regeneration relies on the capacity of cardiomyocytes to proliferate upon injury. To understand the principles of this process after cryoinjury-induced myocardial infarction, we established a spatio-temporal map of mitotic cardiomyocytes and their differentiation dynamics. Immunodetection of phosphohistone H3 and embryonic ventricular heavy chain myosin highlighted two distinct regenerative processes during the early phase of regeneration. The injury-abutting zone comprises a population of cardiac cells that reactivates the expression of embryo-specific sarcomeric proteins and it displays a 10-fold higher mitotic activity in comparison to the injury-remote zone. The undifferentiated cardiomyocytes resemble a blastema-like structure between the original and wound tissues. They integrate with the fibrotic tissue through the fibronectin-tenascin C extracellular matrix, and with the mature cardiomyocytes through upregulation of the tight junction marker, connexin 43. During the advanced regenerative phase, the population of undifferentiated cardiomyocytes disperses within the regenerating myocardium and it is not detected after the termination of regeneration. Although the blastema represents a transient landmark of the regenerating ventricle, the remaining mature myocardium also displays an enhanced mitotic index when compared to uninjured hearts. This suggests an unexpected contribution of a global proliferative activity to restore the impaired cardiac function. Based on these findings, we propose a new model of zebrafish heart regeneration that involves a combination of blastema-dependent epimorphosis and a compensatory organ-wide response.

  14. [Regulation of autophagy on dendritic cells during rat liver regeneration by IPA].

    Qiwen, Wang; Wei, Jin; Cuifang, Chang; Cunshuan, Xu


    To understand the mechanism underlying autophagy in regulating dendritic cells during rat liver regeneration, we used the method of percoll density gradient centrifugation combined with immunomagnetic bead to isolate dendritic cells, the Rat Genome 230 2.0 Array to determine the expression changes of autophagy-related genes, and Ingenuity Pathway Analysis 9.0 (IPA) to determine the autophagy activities. The results indicated that LC3, BECN1, ATG7 and SQSTM1 genes had significant expression changes during rat liver regeneration. There were 593 genes related to autophagy, among which 210 genes were identified as significant. We also showed that the activity of autophagy was enhanced in the priming phase and teminal phase of liver regeneration, weakened in the proliferative stage by comparative analysis method of IPA. The autophagy-related physiological activities mainly included RNA expression, RNA transcription, cell differentiation and proliferation, involving in PPARα/RXRα activation, acute phase response signaling, TREM1 signaling, IL-6 signaling, IL-8 signaling and IL-1 signaling, whose activities were increased or decreased in liver regeneration. Cluster analysis found that P53 and AMPK signaling participated in the regulation of dendritic cells autophagy, with AMPK signaling in the priming phase of liver regeneration, and both signaling pathways in the terminal phase. We conclude that dendritic cells autophagy played an important role in initiation of the immune response in priming phase and depletion of dendritic cells in late phase during rat liver regeneration.

  15. Biomaterials for cardiac regeneration

    Ruel, Marc


    This book offers readers a comprehensive biomaterials-based approach to achieving clinically successful, functionally integrated vasculogenesis and myogenesis in the heart. Coverage is multidisciplinary, including the role of extracellular matrices in cardiac development, whole-heart tissue engineering, imaging the mechanisms and effects of biomaterial-based cardiac regeneration, and autologous bioengineered heart valves. Bringing current knowledge together into a single volume, this book provides a compendium to students and new researchers in the field and constitutes a platform to allow for future developments and collaborative approaches in biomaterials-based regenerative medicine, even beyond cardiac applications. This book also: Provides a valuable overview of the engineering of biomaterials for cardiac regeneration, including coverage of combined biomaterials and stem cells, as well as extracellular matrices Presents readers with multidisciplinary coverage of biomaterials for cardiac repair, including ...

  16. Tissue regeneration with photobiomodulation

    Tang, Elieza G.; Arany, Praveen R.


    Low level light therapy (LLLT) has been widely reported to reduce pain and inflammation and enhance wound healing and tissue regeneration in various settings. LLLT has been noted to have both stimulatory and inhibitory biological effects and these effects have been termed Photobiomodulation (PBM). Several elegant studies have shown the key role of Cytochrome C oxidase and ROS in initiating this process. The downstream biological responses remain to be clearly elucidated. Our work has demonstrated activation of an endogenous latent growth factor complex, TGF-β1, as one of the major biological events in PBM. TGF-β1 has critical roles in various biological processes especially in inflammation, immune responses, wound healing and stem cell biology. This paper overviews some of the studies demonstrating the efficacy of PBM in promoting tissue regeneration.

  17. Bionanomaterials for skin regeneration

    Leonida, Mihaela D


    This book gives a concise overview of bionanomaterials with applications for skin regeneration. The advantages and challenges of nanoscale materials are covered in detail, giving a basic view of the skin structure and conditions that require transdermal or topical applications. Medical applications, such as wound healing, care for burns, skin disease, and cosmetic care, such as aging of the skin and photodamage, and how they benefit from bionanomaterials, are described in detail. A final chapter is devoted to the ethical and social issues related to the use of bionanomaterials for skin regeneration. This is an ideal book for researchers in materials science, medical scientists specialized in dermatology, and cosmetic chemists working in formulations. It can also serve as a reference for nanotechnologists, dermatologists, microbiologists, engineers, and polymer chemists, as well as students studying in these fields.

  18. High Efficiency Somatic Embrogenesis and Plant Regeneration in Suspension Cultures of an Ornamental Ginger Hybrid (Hedychium muluense x cv ‘Starburst’)

    Plants were successfully regenerated via somatic embryogenesis from shoot apex-derived callus of an ornamental ginger hybrid, Hedychium muluense x cv ‘Starburst’. H. muluense is a dwarf species and ‘Starburst’ is a hybrid cultivar with white and very fragrant flowers in a circular, wheel-like arrang...

  19. Proliferative retinopathy and proteinuria predict mortality rate in type 1 diabetic patients from Fyn County, Denmark

    Grauslund, J; Green, A; Sjølie, A K


    .01 (95% CI 0.72-1.42) and 2.04 (1.43-2.91) for patients with non-proliferative and proliferative retinopathy respectively at baseline compared with patients with no retinopathy. After adjusting for proteinuria, HR among patients with proliferative retinopathy lost statistical significance, but still...... remained 1.48 (95% CI 0.98-2.23). The 10 year survival rate of patients who had proliferative retinopathy as well as proteinuria at baseline was 22.2% and significantly lower (pproteinuria only (70.3%), proliferative retinopathy only (79.0%) or neither (86.6%). CONCLUSIONS....../INTERPRETATION: Proliferative retinopathy and proteinuria predict mortality rate in a population-based cohort of type 1 diabetic patients. In combination they act even more strongly. Non-proliferative diabetic retinopathy did not affect survival rate....

  20. [New stimulants of corneal reparative regeneration].

    Egorov, E A; Kalinin, N I; Kiiasov, A P


    The efficacy of corneregel, a drug containing pantothenic acid, a component of coenzyme A, in healing of corneal wounds has been evaluated. The study was carried out on 19 rabbits (38 eyes) with standard corneal defect made with a 5-mm trephine for lamellar transplantation of the cornea, divided into 2 groups: 1) instillations of corneregel (10 eyes) and 0.25% levomycetin solution (10 eyes) and 2) 20% solcoseryl gel (9 eyes) and 0.25% levomycetin (9 eyes). Time course of changes were evaluated by biomicroscopy (fluorescent test), histologically (hematoxylin-eosin staining), and immunohistochemically after 1, 2, 4, 7, 30, and 90 days. Proliferative activity was studied by expression of the proliferating cell nuclear antigen and the migration capacity of cells by expression of alpha-smooth muscle actin. The terms of epithelialization were as follows: corneregel 10 +/- 7 h, 20% solcoseryl gel 108 +/- 10 h, levomycetin 124 +/- 6.93 h. Earlier epithelialization in the corneregel group was apparently due to increased expression of alpha-smooth muscle actin and increase in the cell migration capacity. Hence, corneregel is recommended for practical use as a stimulant of reparative regeneration of the cornea.

  1. Low Temperature Regenerator Study.


    effect. The idealized cycle achieves the same theoretical coefficient of performance (COP) as the theoretical Carnot cycle , whose limiting performance...DISTRIBUTION STATEMENT (of the abstract *irt.,ed in Block 20, iI different it oe) I8. SUPPLEMENTARY NOTES I9. KEY WORDS (Continute on reverse @do of noco*oy...PERFORMANCE ............ 64 3.1 Introduction ..... 0 ... . ......... ... . 64 3.2 Stirling Cycle Analysis ................. 71 3.2.1 Simple Regenerator Model

  2. [Periodontitis and tissue regeneration].

    Yamazaki, Kazuhisa


    Chronic periodontitis is a destructive disease that affects the supporting structures of the teeth including periodontal ligament, cementum, and alveolar bone. If left untreated, patients may lose multiple teeth and extensive prosthetic treatment will be required. In order to re-engineer lost tooth-supporting tissues, various therapeutic modalities have been used clinically. Periodontal regeneration procedures including guided tissue regeneration have achieved substantial effects. However, there are several issues to be solved. They are highly technique-sensitive, applicable to limited cases which are susceptible to treatment, and supposed to have relatively low predictability. Therefore, it is necessary to develop new approaches to improve the predictability and effectiveness of regenerative therapies for periodontal tissues. Recently, the concept of tissue engineering has been introduced to restore lost tissues more effectively where the biological process of healing is mimicked. To achieve this, integration of three key elements is required: progenitor/stem cells, growth factors and the extracellular matrix scaffold. Although it has been shown that implantation of bone marrow-derived mesenchymal stem cells into periodontal osseous defects induced regeneration of cementum, periodontal ligament and alveolar bone in dogs, further extensive preclinical studies are required. On the other hand, application of growth factors, particularly basic fibroblast growth factor in the treatment of human periodontitis, is promising and is now in clinical trial. Furthermore, the rate of release of growth factor from the scaffold also can profoundly affect the results of tissue engineering strategies and the development of new materials is expected. In addition, as tissue regenerative potential is negatively regulated by aging, the effects of aging have to be clarified to gain complete regeneration.

  3. Regeneration of Optic Nerve

    Kwok-Fai So


    Full Text Available The optic nerve is part of the central nervous system (CNS and has a structure similar to other CNS tracts. The axons that form the optic nerve originate in the ganglion cell layer of the retina and extend through the optic tract. As a tissue, the optic nerve has the same organization as the white matter of the brain in regard to its glia. There are three types of glial cells: Oligodendrocytes, astrocytes, and microglia. Little structural and functional regeneration of the CNS takes place spontaneously following injury in adult mammals. In contrast, the ability of the mammalian peripheral nervous system (PNS to regenerate axons after injury is well documented. A number of factors are involved in the lack of CNS regeneration, including: (i the response of neuronal cell bodies against the damage; (ii myelin-mediated inhibition by oligodendrocytes; (iii glial scarring, by astrocytes; (iv macrophage infiltration; and (v insufficient trophic factor support. The fundamental difference in the regenerative capacity between CNS and PNS neuronal cell bodies has been the subject of intensive research. In the CNS the target normally conveys a retrograde trophic signal to the cell body. CNS neurons die because of trophic deprivation. Damage to the optic nerve disconnects the neuronal cell body from its target-derived trophic peptides, leading to the death of retinal ganglion cells. Furthermore, the axontomized neurons become less responsive to the peptide trophic signals they do receive. On the other hand, adult PNS neurons are intrinsically responsive to neurotrophic factors and do not lose trophic responsiveness after axotomy. In this talk different strategies to promote optic-nerve regeneration in adult mammals are reviewed. Much work is still needed to resolve many issues. This is a very important area of neuroregeneration and neuroprotection, as currently there is no cure after traumatic optic nerve injury or retinal disease such as glaucoma, which

  4. Tissue culture and regeneration of an antimalarial plant, Artemisia sieberi Besser

    A. Sharafi


    Full Text Available WHO recommends artemisinin-based combination therapies (ACTs as the most effective choice to treat malaria. For developing transgenic plants with high accumulation of artemisinin (by introducing genes encoding enzymes which regulate the biosynthetic pathway of artemisinin, an efficient protocol for tissue culture and plant regeneration is necessary. In the present study, leaf explants of Artemisia sieberi were cultivated in Murashige & Skoog based medium supplemented by combination of different plant growth regulators including 6-benzyl-aminopurine (BA, α-naphthalene-acetic acid (NAA, indole-3-acetic acid (IAA, picloram (Pic and 2,4-dichlorophenoxyacetic acid (2,4-D. The highest frequency of shoot induction was obtained on MS medium supplemented with 2 mg/L BA plus 0.05 mg/L NAA (95% regeneration and MS medium supplemented with 2 mg/L BA plus 0.5 mg/L IAA (85% regeneration. Rooting was obtained on MS medium supplemented with 0.05 mg/L NAA. The present study has revealed a simple, reliable, rapid and high efficient regeneration system for A. sieberi Besser as a source of artemisinin in short period via adventitious shoot induction procedure.

  5. A valued Indian medicinal plant – Begonia malabarica Lam. : Successful plant regeneration through various explants and field performance

    Sevanan Rajeshkumar


    Full Text Available A cost-effective and efficient protocol has been described in the present work for large-scale and rapid in vitro propagation of a valuable medicinal herb Begonia malabarica Lam. (Begoniaceae by shoot auxillary-bud proliferation and organogenesis on MS medium supplemented with 6-benzylaminopurine (BA; 0.0-8.8 mg/l and indole-3-acetic acid (IAA; 0.0-2.88 mg/l at different concentrations, either alone or in combinations. Initiation of callus formation from the base of the leaf lamina was observed on MS supplemented with BA, IAA and adenine sulphate. Root induction on shoots was achieved on full strength MS with IAA/ indole-3-butyric acid (IBA at different concentrations. MS medium with 4.4 mg/l BA and 1.4 mg/l IAA elicited the maximum number of shoots (10 multiple shoots from nodal explants. Leaf-based callus differentiated into more than 28 shoots on MS with 150 mg/l adenine sulphate. The regenerated shoots were rooted on MS with 1.2 mg/l IBA within ten days. Almost 95% of the rooted shoots survived hardening when transferred to the field. The regenerated plants did not show any morphological change and variation in levels of secondary metabolites when compared with the mother stock. Thus, a reproduction of B. malabarica was established through nodal and leaf explants. This protocol can be exploited for conservation and commercial propagation of this medical plant in the Indian subcontinent and might be useful for genetic improvement programs.



    Objective To explore the mechanisms of differentiation and development of pancreatic endocrine cells as well as pancreatic regeneration. Methods Human embryonic pancreatic tissue at 7-14 weeks of gestation was collected. Diabetes mellitus rat model was induced with 65 mg/kg of streptozotocin. Insulin, glucagon, somatostatin, nestin, and cytokeratin 19 (CK19)of pancreatic tissues were observed by immunohistochemistry. Results At 9 weeks of gestation, pancreatic epithelial cells began to co-express insulin, glucagon, somatostatin, and CK19 before migration. Islet cells gradually congregated along with the increase of aging, and at 14 weeks of gestation histological examination showed islet formation. At 12 weeks of gestation, nestin-positive cells could be seen in the pancreatic mesenchyme. During early embryogenesis, islet cells of pancreatic ducts co-expressed insulin, glucagon, and somatostatin. During pancreatic regeneration after damage, nestin expression of islet cells increased. Conclusion In the early stage of embryogenesis, islet cells of primary pancreatic ducts can be differentiated to multipotential endocrine cells before migration. During tissue regeneration, pancreatic stem cells may differentiate and proliferate to form pancreatic islet.

  7. Plant regeneration from protoplasts of hydroxyproline resistant cell line in Onobrychis viciaefolia



    An efficient protocol for plant regeneration from protoplasts of hydroxyproline(HYP)resistant cell line of Onobrychis viciaefolia was established.In SH medium supplemented with 1mg/L2,4-dichlorophenoxy-acetic acid(2,4-D),0.5mg/L kinetin(KT)and 0.2mg/L naphthalene acetic acid(NAA),the division frequency of protoplastderived cells reached up to over 60%,and microcalli were obtained in 5-6wk.Upon transferring them on agar solidified MS medium plus 2mg/L indole-3-acetic acid (IAA),shoots were induced.After cultivating them on MS medium with or without IAA,roots were regenerated.Chromosome number of all protoplast-regenerated plants examined were normal(2n=28).The protoplast-derived calli and plants grew vigorously on the medium containing 10 mmol/L HYP.

  8. Contagion in Mass Killings and School Shootings: e0117259

    Sherry Towers; Andres Gomez-Lievano; Maryam Khan; Anuj Mubayi; Carlos Castillo-Chavez


    ... to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts. Methods Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings...

  9. Germination, seedling growth and relative water content of shoot in ...



    Aug 18, 2008 ... ... and higher levels of dry matter under water deficient condition (Manga and .... medium seeds with the increase of stress levels. The shoot length of .... It is important that drought resistance is characterized by small reduction ...

  10. Early signs of infection in Cacao swollen shoot virus (CSSV ...



    Feb 1, 2010 ... subscript representing product region on Agou 1 genome (L14546). tissues were then ..... infected plants, and discovered proliferation of xylem and phloem cells ..... and differentiation of cocoa swollen shoot virus isolates.

  11. Application of Monte Carlo Simulations to Improve Basketball Shooting Strategy

    Min, Byeong June


    The underlying physics of basketball shooting seems to be a straightforward example of the Newtonian mechanics that can easily be traced by numerical methods. However, a human basketball player does not make use of all the possible basketball trajectories. Instead, a basketball player will build up a database of successful shots and select the trajectory that has the greatest tolerance to small variations of the real world. We simulate the basketball player's shooting training as a Monte Carlo sequence to build optimal shooting strategies, such as the launch speed and angle of the basketball, and whether to take a direct shot or a bank shot, as a function of the player's court positions and height. The phase space volume that belongs to the successful launch velocities generated by Monte Carlo simulations are then used as the criterion to optimize a shooting strategy that incorporates not only mechanical, but human factors as well.

  12. Effect of micro-environmental factors on natural regeneration of Sal (Shorea robusta)

    J. V. Tyagi; Rakesh Kumar; S. L. Srivastava; R. D. Singh


    Micro-environmental factors viz.,soil moisture and light intensity are important factors that affect natural regeneration in forests.These factors vary spatially depending on the overhead canopy density of the forest.The present study focused on studying the effect of variation of soil moisture and light intensity on natural regeneration ofsal species (Shorea robusta) under different micro-environments due to overhead canopy of varying forest density.Experimental plots of 40m× 40m size were laid under different overhead canopy densities in a small sal forested watershed in the foot hills of Himalayas in Nainital District of Uttarakhand State,India.The plots were monitored on a long term basis for soil moisture at multi depths,light intensity and natural regeneration of sal.The results of the study rev~led that the natural regeneration was highest under C1 (up to-0.30) canopy followed by C2 (0.30-0.50),and C3 (0.50-0.70) canopies.The C3 canopy showed the dying back of sal shoots over 4 years of study.The highest R2 value of linear regression between incremental score of plot regeneration and average soil moisture content was obtained as 0.156 for average soil moisture content during non-monsoon months at 100 cm depth.The R2 value between incremental score of plot regeneration and annual average light intensity was obtained as 0.688 which indicated that the regeneration is largely dependent on the light intensity conditions during the year.The multiple linear regression analysis between the incremental score of regeneration and the average light intensity and average soil moisture content revealed that that about 80% of variation in regeneration is explained by both the factors.

  13. Acquiring competence for shoot development in Arabidopsis: ARR2 directly targets A-type ARR genes that are differentially activated by CIM preincubation.

    Che, Ping; Lall, Sonia; Howell, Stephen H


    Shoots can be regenerated from roots in Arabidopsis by treating root explants with cytokinin, however, shoot regeneration requires preincubation on callus induction medium (CIM) prior to induction on cytokinin-rich shoot induction medium (SIM). A cytokinin-inducible marker gene, RESPONSE REGULATOR 15 (ARR15), was identified through a "CIM dropout experiment" with similar requirements for CIM preincubation. The requirements for ARR15 contrasted to ARR5, another cytokinin-inducible ARR gene that does not require CIM preincubation. We show here that despite their differences, both ARR5 and ARR15 are direct targets of the transcriptional B-type response regulator, ARR2. This was demonstrated by identifying genes upregulated following beta estradiol induced nuclear relocation of an ARR2-estradiol receptor fusion protein. The differences in CIM preincubation requirements for ARR5 and ARR15 expression indicate an additional layer of control for these A-type ARR genes during SIM incubation. For ARR15, the CIM requirement is a transcriptional effect, because the expression of ARR15 promoter:GUS reporter gene constructs is also affected by CIM preincubation. A testable model is that transcription of ARR15, but not ARR5, is blocked by a repressor and that the effects of the repressor are relieved by CIM preincubation.

  14. Connective Auxin Transport in the Shoot Facilitates Communication between Shoot Apices.

    Bennett, Tom; Hines, Geneviève; van Rongen, Martin; Waldie, Tanya; Sawchuk, Megan G; Scarpella, Enrico; Ljung, Karin; Leyser, Ottoline


    The bulk polar movement of the plant signaling molecule auxin through the stem is a long-recognized but poorly understood phenomenon. Here we show that the highly polar, high conductance polar auxin transport stream (PATS) is only part of a multimodal auxin transport network in the stem. The dynamics of auxin movement through stems are inconsistent with a single polar transport regime and instead suggest widespread low conductance, less polar auxin transport in the stem, which we term connective auxin transport (CAT). The bidirectional movement of auxin between the PATS and the surrounding tissues, mediated by CAT, can explain the complex auxin transport kinetics we observe. We show that the auxin efflux carriers PIN3, PIN4, and PIN7 are major contributors to this auxin transport connectivity and that their activity is important for communication between shoot apices in the regulation of shoot branching. We propose that the PATS provides a long-range, consolidated stream of information throughout the plant, while CAT acts locally, allowing tissues to modulate and be modulated by information in the PATS.

  15. The Hidden Advantage in Shoot/Don’t Shoot Simulation Exercises for Police Recruit Training

    Amanda Davies


    Full Text Available During the past thirty-five years, developments in computer-related technology have been providing increasingly more sophisticated simulation alternatives for training law enforcement officers. Such developments have leveraged on the back of progress achieved in the aviation, military and medical professions as law enforcement educators seek to address the challenges of training for high-risk, high-stakes professional environments. While globally, simulation based learning exercises are at the forefront in use-of-force training with firearms for police recruits there is limited published research which views the influence of these exercises on operational practice through the lens of the police recruit as they engage with the demands of their volatile, unpredictable workplace. This paper discusses a case study of a cohort of 372 police recruits whose police academy education program included participation in simulation based learning exercises centred on decision making in use-of-force. The pivotal inclusion in the study was the opportunity for the police recruits to reflect on the influence of the simulation exercise experience from an operational perspective. The study revealed an unvoiced advantage—while trainers are focusing on the amount of ammunition used, the marksmanship accuracy, and the justification for the use-of-force, the students are unconsciously building a repertoire of realistic experiences as a reference library for the moment of decision in real life shoot/don’t shoot incidents.

  16. Effect of cytokinins on shoot apical meristem in Nicotiana tabacum

    Uzelac Branka


    Full Text Available Cytokinins are involved in plant cell proliferation leading to plant growth and morphogenesis. The size, activity and maintenance of the shoot apical meristem (SAM are defined by a balanced rate of mitotic cell divisions and functional cell differentiation that are controlled by cytokinins. In order to investigate the effect of exogenous cytokinin on SAM, morpho-anatomical changes in the shoot apices of tobacco treated with benzyladenine (BA were compared to those of untreated control plants.

  17. Recent Developments in the Methods of Estimating Shooting Distance

    Arie Zeichner


    Full Text Available A review of developments during the past 10 years in the methods of estimating shooting distance is provided. This review discusses the examination of clothing targets, cadavers, and exhibits that cannot be processed in the laboratory. The methods include visual/microscopic examinations, color tests, and instrumental analysis of the gunshot residue deposits around the bullet entrance holes. The review does not cover shooting distance estimation from shotguns that fired pellet loads.

  18. Coumarins and alkaloids in shoot culture of Ruta graveolens L.

    Halina Ekiert


    Full Text Available A shoot culture of Ruta graveolens L. (Rutaceae was maintained in the stationary liquid phase. From the cultured shoots seven compounds were isolated and identified as psoralen, bergapten, xanthotoxin, isopimpinellin (linear furanocoumarins, rutamarin (linear dihydrofuranocoumarin, kokusaginine and skimmianine (furanoquinoline alkaloids by spectral methods. The compounds are known as secondary metabolites of the intact plant, as well as its cell and tissue cultures.

  19. Antibacterial, antioxidant and cell proliferative properties of Coccinia grandis fruits

    Prashant Sakharkar


    Full Text Available Objective: Little knowledge is available on the antimicrobial and antioxidant properties of Coccina grandis fruits and no study has reported on its cell proliferative property. The aim of this study was to examine the antimicrobial, antioxidant and cell proliferative property of fruits of C. grandis. Material and Methods: Fruits of C. grandis were extracted using water; ethanol and acetone by cold and hot Soxhlet extraction. The antibacterial activities of the extracts were tested against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa using the modified Kirby-Bauer diffusion method and compared against erythromycin. The antioxidant property was determined using Cayman's antioxidant assay; whereas cell proliferation/cytotoxic properties were evaluated using the Cell Titer 96 Aqueous One Solution Cell MTS assay with MDA-MB 321 breast cancer cells. Data were analyzed for correlation and differences using unpaired student's t-test and one-way ANOVA. A p value of Results: Both cold and hot ethanol and acetone extracts of C. grandis fruits showed some degree of bacterial growth inhibition. Acetone extracts exhibited higher antibacterial activity. Both ethanol extracts showed antioxidant property when compared with standard Trolox. In contrary to cytotoxicity, all four extracts showed cell proliferation compared to controls at different concentrations. However, acetone extracts exhibited greater cell proliferation compared to ethanol extracts and cold extracts performed better than the hot extracts. Conclusion: C. grandis fruits exhibited some degree of antimicrobial, antioxidant and cell proliferative properties. Further investigation is warranted to isolate, confirm and characterize phytochemicals that are responsible for the medicinal properties observed.

  20. Significance of CD163-Positive Macrophages in Proliferative Glomerulonephritis.

    Li, Jun; Liu, Chang-Hua; Xu, Dao-Liang; Gao, Bo


    CD163, a marker of M2 macrophages, possesses anti-inflammatory properties. This study aims to investigate the clinicopathological significance of CD163-positive macrophages in proliferative glomerulonephritis. Renal tissue samples from patients with lupus nephritis (LN, n = 22), antineutrophil cytoplasmic autoantibody (ANCA)-associated pauci-immune necrotizing glomerulonephritis (PNGN, n = 10), type 1 membranoproliferative glomerulonephritis (n = 5), minimal change disease (n = 8) and normal control kidneys (n = 3) were included in this study. The expression of CD163, CD68, CD20 and CD3 in renal tissues was detected by immunohistochemistry or immunofluorescence. The level of urinary neutrophil gelatinase-associated lipocalin (NGAL) was determined by enzyme-linked immunosorbent assay. CD163 was mainly expressed in active crescentic glomerulonephritis, proliferative glomerular lesions and areas of tubulointerstitial injury. Patients with LN-IV and PNGN had numerous CD163-positive cells in glomerular and acute tubulointerstitial lesions. CD163-positive cells in glomeruli positively correlated to proteinuria yet negatively correlated to estimated glomerular filtration rate. There was a positive correlation between the number of CD163 cells in acute tubulointerstitial lesions and NGAL levels, whereas a negative correlation between CD163 numbers and estimated glomerular filtration rate. The number of CD163-positive cells in crescentic glomerulonephritis was more than other groups. In LN, the number of CD163 cells in the tubulointerstitial and glomerular lesions had a positive correlation with activity index. Dual staining showed that CD163-positive cells also expressed CD68, although they did not show any staining for CD20 or CD3. CD163-positive macrophages were involved in the pathogenesis of proliferative glomerular lesions, active crescentic glomerulonephritis and acute tubular injury of patients with PNGN and active LN.

  1. In vitro Plant Regeneration from the Mature Tissue of Navel Orange (Citrus sinensis L. Osbeck) by Direct Organogenesis

    HUANG Jia-quan; YIN Li-yan; YANG Xiao-hong; SUN Zhong-hai


    An efficient in vitro regeneration system by direct organogenesis from mature nodal and internodal stem segments of Newhall navel orange (Citrus sinensis L. Osbeck) was developed. Illuminating conditions together with plant growth regulators affected the adventitious bud regeneration frequency and efficiency. The initial 15 d darkness inoculation is beneficial for the adventitious bud regeneration. The highest regeneration frequency (85.2%) and bud formation efficiency (3.7 per responsive internodal stem segment) were obtained in the media supplemented with 1.0 mg L-1 BAP and 0.5 mg L-1 NAA. ABA at 0.2 mg L-1 positively affected the bud formation efficiency, which amounted to 8.5 buds per internodal segment in the presence of BAP at 1.0 mg L-1. The adventitious shoots successfully rooted and were transferred to the soil.

  2. Effect of nickel on regeneration in Jatropha curcas L. and assessment of genotoxicity using RAPD markers

    Sarkar, Tanmoy


    The aim of the present study was to determine the effect of nickel on shoot regeneration in tissue culture as well as to identify polymorphisms induced in leaf explants exposed to nickel through random amplified polymorphic DNA (RAPD). In vitro leaf explants of Jatropha curcas were grown in nickel amended Murashige and Skoog (MS) medium at four different concentrations (0, 0.01, 0.1, 1 mM) for 3 weeks. Percent regeneration, number of shoots produced and genotoxic effects were evaluated by RAPD using leaf explants obtained from the first three treatments following 5 weeks of their subsequent subculture in metal free MS medium. Percent regeneration decreased with increase in addition of nickel to the medium up to 14 days from 42.31% in control to zero in 1.0 mM. The number of shoot buds scored after 5 weeks was higher in control as compared to all other treatments except in one of the metal free subculture medium wherein the shoot number was higher in 0.01 mM treatment (mean = 7.80) than control (mean = 7.60). RAPD analysis produced only 5 polymorphic bands (3.225%) out of a total of 155 bands from 18 selected primers. Only three primers OPK-19, OPP-2, OPN-08 produced polymorphic bands. The dendrogram showed three groups A, B, and C. Group A samples showed 100% genetic similarity within them. Samples between groups B and C were more genetically distant from each other as compared to samples between groups A and B as well as groups A and C. Cluster analysis based on RAPD data correlated with treatments. © 2010 Springer Science+Business Media, LLC.

  3. Surveys of harvest technology of winter bamboo shoots

    LIU Tian-hu


    Winter bamboo shoots are widely used in Asian cuisine. We surveyed growth depth (tail depth and root depth), harvest speed, and harvest processes to provide information for developing new harvest technology. The tail depth of most winter bamboo shoots was 100-350 mm below the soil surface, and the root depth was 200-500 mm below the soil surface. Most winter bamboo shoots were difficult to locate with only the naked eye. The digging depth was 200-500 mm to cut winter bamboo shoots from the root. The highest harvest rate was 7.75 times faster than the slowest one and the average harvest speed ratio of men: women was about 1.71:1. The harvest process of winter bamboo shoots was divisible into three steps: searching, digging a hole (around the shoot) and cutting the root. The ratio of searching time to the sum of digging and cutting time was about 8:1, showing that searching required more time than digging and cutting together.

  4. Micropropagation of Asparagus by in vitro shoot culture.

    Stajner, Nataša


    Asparagus officinalis is most extensively studied species within the genus Asparagus, which is well known as garden asparagus. This species is dioecious with unisexual flowers, which means that generative propagation gives roughly equal number of male and female plants. Male plants are high yielders and preferred commercially over female plants. Tissue culture techniques could efficiently promote vegetative propagation of male plants and pave the way for efficient plant breeding.This chapter describes an efficient micropropagation protocol for developing rapid growing in vitro Asparagus shoot cultures. The source of explants, inoculation, and shoot proliferation, followed by shoot propagation, rooting, and acclimatization is described. The optimal medium for Asparagus micropropagation described in this chapter is composed of MS macro- and microelements and a combination of auxins and cytokinins. Plant growth regulators NAA, kinetin, and BA were used in various concentrations. Three different media representing the whole micropropagation protocol of Asparagus are described; medium for shoot initiation, medium for shoot multiplication, and medium for root formation. By in vitro propagation of Asparagus, root initiation is difficult, but can be promoted by adding growth retardant ancymidol which also greatly promotes shoot development and suppresses callus formation.

  5. Ferns: the missing link in shoot evolution and development

    Andrew Robert George Plackett


    Full Text Available Shoot development in land plants is a remarkably complex process that gives rise to an extreme diversity of forms. Our current understanding of shoot developmental mechanisms comes almost entirely from studies of angiosperms (flowering plants, the most recently diverged plant lineage. Shoot development in angiosperms is based around a layered multicellular apical meristem that produces lateral organs and/or secondary meristems from populations of founder cells at its periphery. In contrast, non-seed plant shoots develop from either single apical initials or from a small population of morphologically distinct apical cells. Although developmental and molecular information is becoming available for non-flowering plants, such as the model moss Physcomitrella patens, making valid comparisons between highly divergent lineages is extremely challenging. As sister group to the seed plants, the monilophytes (ferns and relatives represent an excellent phylogenetic midpoint of comparison for unlocking the evolution of shoot developmental mechanisms, and recent technical advances have finally made transgenic analysis possible in the emerging model fern Ceratopteris richardii. This review compares and contrasts our current understanding of shoot development in different land plant lineages with the aim of highlighting the potential role that the fern C. richardii could play in shedding light on the evolution of underlying genetic regulatory mechanisms.

  6. Shoot-derived cytokinins systemically regulate root nodulation.

    Sasaki, Takema; Suzaki, Takuya; Soyano, Takashi; Kojima, Mikiko; Sakakibara, Hitoshi; Kawaguchi, Masayoshi


    Legumes establish symbiotic associations with nitrogen-fixing bacteria (rhizobia) in root nodules to obtain nitrogen. Legumes control nodule number through long-distance communication between roots and shoots, maintaining the proper symbiotic balance. Rhizobial infection triggers the production of mobile CLE-RS1/2 peptides in Lotus japonicus roots; the perception of the signal by receptor kinase HAR1 in shoots presumably induces the production of an unidentified shoot-derived inhibitor (SDI) that translocates to roots and blocks further nodule development. Here we show that, CLE-RS1/2-HAR1 signalling activates the production of shoot-derived cytokinins, which have an SDI-like capacity to systemically suppress nodulation. In addition, we show that LjIPT3 is involved in nodulation-related cytokinin production in shoots. The expression of LjIPT3 is activated in an HAR1-dependent manner. We further demonstrate shoot-to-root long-distance transport of cytokinin in L. japonicus seedlings. These findings add essential components to our understanding of how legumes control nodulation to balance nutritional requirements and energy status.

  7. Biomaterial Selection for Tooth Regeneration


    Biomaterials are native or synthetic polymers that act as carriers for drug delivery or scaffolds for tissue regeneration. When implanted in vivo, biomaterials should be nontoxic and exert intended functions. For tooth regeneration, biomaterials have primarily served as a scaffold for (1) transplanted stem cells and/or (2) recruitment of endogenous stem cells. This article critically synthesizes our knowledge of biomaterial use in tooth regeneration, including the selection of native and/or s...

  8. Establishment of regeneration and transformation system in Egyptian sesame (Sesamum indicum L.) cv Sohag 1.

    Al-Shafeay, Amal F; Ibrahim, Ahmed S; Nesiem, Mohamed R; Tawfik, Mohamed S


    Sesame (Sesamum indicum L.) is an important oil crop in many tropical and sub-tropical regions of the world, yet has received little attention in applying modern biotechnology in its improvement due to regeneration and transformation difficulties. Here within, we report the successful production of transgenic fertile plants of sesame (cv Sohag 1), after screening several cultivars. Agrobacterium tumefaciens- carrying the pBI121 plasmid {neomycin phosphotransferase gene (NPTII) and a β-glucuronidase gene (GUS)} was used in all experiments. Recovery of transgenic sesame shoots was achieved using shoot induction medium (Murashige and Skoog MS basal salt mixture + Gamborg's B5 vitamins + 2.0 mg/l BA + 1.0 mg/l IAA + 5.0 mg/l AgNO3 + 30.0 g/l sucrose + 7.0 g/l agar + 200 mg/l cefotaxime and 25 mg/l kanamycin) and shoots were rooted on MS medium + B5 vitamins + 1.0 mg/l IAA + 10.0 g/l sucrose and 7.0 g/l agar. Rooted shoots were transplanted into soil and grown to maturity in greenhouse. Incorporation and expression of the GUS gene into T0 sesame plants was confirmed using polymerase chain reaction (PCR), reverse transcriptase-PCR (RT-PCR) and GUS histochemical assay. Several factors were found to be important for regeneration and transformation in sesame. The most effective were plant genotype and the addition of AgNO3 for successful recovery of sesame shoots. Co-cultivation time and optical density of the Agrobacterium were also critical for sesame transformation. This work is an attempt to open the door for further genetic improvement of sesame using important agronomic traits.

  9. The effect of triacontanol on shoot multiplication and production of antioxidant compounds in shoot cultures of Salvia officinalis L.

    Izabela Grzegorczyk


    Full Text Available This report describes the effect of triacontanol on shoot multiplication and production of antioxidant compounds (carnosic acid, carnosol and rosmarinic acid in S. officinalis cultures grown on MS basal medium (agar solidified medium supplemented with 0.1 mg l-1 IAA, 0.45 mg l-1 BAP. It was found that shoot proliferation significantly increased when triacontanol at concentrations of 5, 10 or 20 µg l-1 was added to the medium. HPLC analysis of acetone and methanolic extracts of sage shoots showed that the production of diterpenoids, carnosic acid/carnosol ratio, as well as, contents of rosmarinic acid were also affected by the treatment with triacontanol. The highest stimulation effect of triacontanol was observed on the production of carnosol, where the treatment with 20 µg l l-1 increased the content of this diterpenoid 4.5-fold compared to that in the control (sage shoots growing on MS basal medium, only.

  10. Understanding Urban Regeneration in Turkey

    Candas, E.; Flacke, J.; Yomralioglu, T.


    In Turkey, rapid population growth, informal settlements, and buildings and infrastructures vulnerable to natural hazards are seen as the most important problems of cities. Particularly disaster risk cannot be disregarded, as large parts of various cities are facing risks from earthquakes, floods and landslides and have experienced loss of lives in the recent past. Urban regeneration is an important planning tool implemented by local and central governments in order to reduce to disaster risk and to design livable environments for the citizens. The Law on the Regeneration of Areas under Disaster Risk, commonly known as the Urban Regeneration Law, was enacted in 2012 (Law No.6306, May 2012). The regulation on Implementation of Law No. 6306 explains the fundamental steps of the urban regeneration process. The relevant institutions furnished with various authorities such as expropriation, confiscation and changing the type and place of your property which makes urban regeneration projects very important in terms of property rights. Therefore, urban regeneration projects have to be transparent, comprehensible and acceptable for all actors in the projects. In order to understand the urban regeneration process, the legislation and projects of different municipalities in Istanbul have been analyzed. While some steps of it are spatial data demanding, others relate to land values. In this paper an overview of the urban regeneration history and activities in Turkey is given. Fundamental steps of the urban regeneration process are defined, and particularly spatial-data demanding steps are identified.

  11. Synthetic Phage for Tissue Regeneration

    So Young Yoo


    Full Text Available Controlling structural organization and signaling motif display is of great importance to design the functional tissue regenerating materials. Synthetic phage, genetically engineered M13 bacteriophage has been recently introduced as novel tissue regeneration materials to display a high density of cell-signaling peptides on their major coat proteins for tissue regeneration purposes. Structural advantages of their long-rod shape and monodispersity can be taken together to construct nanofibrous scaffolds which support cell proliferation and differentiation as well as direct orientation of their growth in two or three dimensions. This review demonstrated how functional synthetic phage is designed and subsequently utilized for tissue regeneration that offers potential cell therapy.

  12. Regenerable solid imine sorbents

    Gray, McMahan; Champagne, Kenneth J.; Fauth, Daniel; Beckman, Eric


    Two new classes of amine-based sorbents are disclosed. The first class comprises new polymer-immobilized tertiary amine sorbents; the second class new polymer-bound amine sorbents. Both classes are tailored to facilitate removal of acid anhydrides, especially carbon dioxide (CO.sub.2), from effluent gases. The amines adsorb acid anhydrides in a 1:1 molar ratio. Both classes of amine sorbents adsorb in the temperature range from about C. upwards to C. and can be regenerated by heating upwards to C.

  13. Regeneration Responses to Management for Old-Growth Characteristics in Northern Hardwood-Conifer Forests

    Aviva J. Gottesman


    Full Text Available Successful tree regeneration is essential for sustainable forest management, yet it can be limited by the interaction of harvesting effects and multiple ecological drivers. In northern hardwood forests, for example, there is uncertainty whether low-intensity selection harvesting techniques will result in adequate and desirable regeneration. Our research is part of a long-term study that tests the hypothesis that a silvicultural approach called “structural complexity enhancement” (SCE can accelerate the development of late-successional forest structure and functions. Our objective is to understand the regeneration dynamics following three uneven-aged forestry treatments with high levels of retention: single-tree selection, group selection, and SCE. Regeneration density and diversity can be limited by differing treatment effects on or interactions among light availability, competitive environment, substrate, and herbivory. To explore these relationships, manipulations and controls were replicated across 2 ha treatment units at two Vermont sites. Forest inventory data were collected pre-harvest and periodically over 13 years post-harvest. We used mixed effects models with repeated measures to evaluate the effect of treatment on seedling and sapling density and diversity (Shannon–Weiner H’. The treatments were all successful in recruiting a sapling class with significantly greater sapling densities compared to the controls. However, undesirable and prolific beech (Fagus americana sprouting dominates some patches in the understory of all the treatments, creating a high degree of spatial variability in the competitive environment for regeneration. Multivariate analyses suggest that while treatment had a dominant effect, other factors were influential in driving regeneration responses. These results indicate variants of uneven-aged systems that retain or enhance elements of stand structural complexity—including old-growth characteristics

  14. Connective tissue fibroblast properties are position-dependent during mouse digit tip regeneration.

    Yuanyuan Wu

    Full Text Available A key factor that contributes to the regenerative ability of regeneration-competent animals such as the salamander is their use of innate positional cues that guide the regeneration process. The limbs of mammals has severe regenerative limitations, however the distal most portion of the terminal phalange is regeneration competent. This regenerative ability of the adult mouse digit is level dependent: amputation through the distal half of the terminal phalanx (P3 leads to successful regeneration, whereas amputation through a more proximal location, e.g. the subterminal phalangeal element (P2, fails to regenerate. Do the connective tissue cells of the mammalian digit play a role similar to that of the salamander limb in controlling the regenerative response? To begin to address this question, we isolated and cultured cells of the connective tissue surrounding the phalangeal bones of regeneration competent (P3 and incompetent (P2 levels. Despite their close proximity and localization, these cells show very distinctive profiles when characterized in vitro and in vivo. In vitro studies comparing their proliferation and position-specific interactions reveal that cells isolated from the P3 and P2 are both capable of organizing and differentiating epithelial progenitors, but with different outcomes. The difference in interactions are further characterized with three-dimension cultures, in which P3 regenerative cells are shown to lack a contractile response that is seen in other fibroblast cultures, including the P2 cultures. In in vivo engraftment studies, the difference between these two cell lines is made more apparent. While both P2 and P3 cells participated in the regeneration of the terminal phalanx, their survival and proliferative indices were distinct, thus suggesting a key difference in their ability to interact within a regeneration permissive environment. These studies are the first to demonstrate distinct positional characteristics of

  15. Connective tissue fibroblast properties are position-dependent during mouse digit tip regeneration.

    Wu, Yuanyuan; Wang, Karen; Karapetyan, Adrine; Fernando, Warnakulusuriya Akash; Simkin, Jennifer; Han, Manjong; Rugg, Elizabeth L; Muneoka, Ken


    A key factor that contributes to the regenerative ability of regeneration-competent animals such as the salamander is their use of innate positional cues that guide the regeneration process. The limbs of mammals has severe regenerative limitations, however the distal most portion of the terminal phalange is regeneration competent. This regenerative ability of the adult mouse digit is level dependent: amputation through the distal half of the terminal phalanx (P3) leads to successful regeneration, whereas amputation through a more proximal location, e.g. the subterminal phalangeal element (P2), fails to regenerate. Do the connective tissue cells of the mammalian digit play a role similar to that of the salamander limb in controlling the regenerative response? To begin to address this question, we isolated and cultured cells of the connective tissue surrounding the phalangeal bones of regeneration competent (P3) and incompetent (P2) levels. Despite their close proximity and localization, these cells show very distinctive profiles when characterized in vitro and in vivo. In vitro studies comparing their proliferation and position-specific interactions reveal that cells isolated from the P3 and P2 are both capable of organizing and differentiating epithelial progenitors, but with different outcomes. The difference in interactions are further characterized with three-dimension cultures, in which P3 regenerative cells are shown to lack a contractile response that is seen in other fibroblast cultures, including the P2 cultures. In in vivo engraftment studies, the difference between these two cell lines is made more apparent. While both P2 and P3 cells participated in the regeneration of the terminal phalanx, their survival and proliferative indices were distinct, thus suggesting a key difference in their ability to interact within a regeneration permissive environment. These studies are the first to demonstrate distinct positional characteristics of connective tissue

  16. Amniocar as a proliferative medium for mesenchymal cells

    V. V. Chestkov


    Full Text Available Objectives. To develop the Amniocar nutrient medium that contains fetal calf serum (FCS and growth factors cocktail for mass cultivation of human fibroblasts. To study proliferative activity of the medium on cultures of HUVEC cells of mesenchymal origin and mesenchymal stromal cells, as well as on cell culture of human amniotic fluid.Materials and methods. Determination of the rate of accumulation of the cellular mass and cell morphology in the course of cultivation of cells of various histogenesis in the Amniocar medium and nutrient medium that contains 10 % of FCS.Results. It has been demonstrated that the Amniocar medium is prevalent as compared to the standard DMEM medium with 10 % of FCS by 2 to 5 times for cultivation of skin fibroblasts, HUVEC, and mesenchymal stem cells. The Amniocar medium increased the quantity of endothelial cells that enter mitosis and maintained the culture of HUVEC cells with prolonged passaging in vitro. Clonal cultivation of human amniotic fluid cells in the Amniocar medium secured development of colonies of both fibroblast and epithelial type.Conclusions. Proliferative Amniocar medium is efficient for mass cultivation of various cells of mesenchymal origin and can be used for diagnostic purposes in medical genetics, oncology, etc.

  17. Potentiation of lymphocyte proliferative responses by nickel sulfide

    Jaramillo, A.; Sonnenfeld, G.


    Crystalline nickel sulfide (NiS) induced a spleen cell proliferation that resembles a mixed lymphocyte reaction (MLR). It depended on cell-cell interaction, induced high levels of interleukin-1 (IL-1) and interleukin-2 (IL-2) and the responding cell subpopulation was composed of CD4+ T lymphocytes. Furthermore, the proliferation was inhibited in a dose-dependent manner by magnesium. Crystalline NiS also increased significantly the spleen cell proliferative response to concanavalin A (Con A) and lipopolysaccharide (LPS) with magnesium potentiating the combined effects of crystalline NiS and mitogens. Interestingly, crystalline NiS did not show any effect on the induction of IL-2 by Con A. The results described herein suggest that crystalline NiS can potentiate both antigenic (MLR) and mitogenic (Con A and LPS) proliferative responses in vitro. Crystalline NiS appears to potentiate these responses by acting in the form of ionic nickel on several intracellular targets for which magnesium ions have different noncompetitive interactions. The effects of magnesium on the potentiating action of crystalline NiS are different depending upon the type of primary stimulatory signal for proliferation (mitogenic or antigenic).

  18. Sequence stratigraphic control on prolific HC reservoir development, Southwest Iran

    Lasemi, Y.; Kondroud, K.N.


    An important carbonate formation in the Persian Gulf and the onshore oil fields of Southwest Iran is the Lowermost Cretaceous Fahliyan formation. The formation in Darkhowain field consists of unconformity-bounded depositional sequences containing prolific hydrocarbon reservoirs of contrasting origin. Located in the high stand systems tract (HST) of the lower sequence encompassing over 200m of oil column are the most prolific reservoir. Another reservoir is over 80m thick consisting of shallowing-upward cycles that are best developed within the transgressive systems tract of the upper sequence. Vertical facies distribution and their paleobathymetry and geophysical log signatures of the Fahliyan formation in the Darkhowain platform reveal the presence of two unconformity-bounded depositional sequences in Vail et al., Van Wagoner et al., and Sarg. The Fahliyan formation mainly consists of platform carbonates composed of restricted bioclastic lime mudstone to packstone of the platform interior, Lithocodium boundstone or ooid-intraclast-bioclast grainstone of the high energy platform margin and the bioclast packstone to lime mudstone related to the off-platform setting.

  19. Can the combination of localized "proliferative therapy" with "minor ozonated autohemotherapy" restore the natural healing process?

    Gracer, R I; Bocci, V


    Regenerative injection therapy (RIT), also known as proliferative therapy, has been used for over 30 years in the USA in patients with spinal and peripheral joint and ligamentous pathologies. It involves the injection of mildly irritating medications onto ligaments and tendons, most commonly at origins and insertions. These injections cause a mild inflammatory response which "turns on" the normal healing process and results in the regeneration of these structures. At the same time they strengthen and become less sensitive to pain through a combination of neurolysis of small nerve fibers (C-fibers) and increased stability of the underlying structures. Oxygen/ozone therapy is a well established complementary therapy practiced in many European countries. The ozone dissolves in body fluids and immediately reacts with biomolecules generating messengers responsible for biological and therapeutic activities. This results in an anti inflammatory response, which also results in a similar trophic reaction to that of RIT. It is logical to expect that combining these two modalities would result in enhanced healing and therefore improved clinical outcomes. Oxygen/ozone therapy, accomplished by autohemotherapy (AHT), is performed by either administering ozonated blood intravenously (Major AHT) or via intramuscular route (Minor AHT). These procedures result in stimulation of the immune and healing systems. Our concept is that the local injection of this activated blood injected directly to the ligamentous areas that are also being treated with RIT will act as a direct stimulation to the healing process. In addition, combining this with intravenous major AHT should stimulate the immune system to augment and support this process. RIT and oxygen/ozone therapy have been extensively studied separately. We propose a study of lumbosacral ligamentous pain to explore this therapeutic combination. We hope that this paper will stimulate general interest in this area of medicine and result

  20. Complex interaction between proliferative kidney disease, water temperature and concurrent nematode infection in brown trout.

    Schmidt-Posthaus, Heike; Steiner, Pascale; Müller, Barbara; Casanova-Nakayama, Ayako


    Proliferative kidney disease (PKD) is a temperature-dependent disease caused by the myxozoan Tetracapsuloides bryosalmonae. It is an emerging threat to wild brown trout Salmo trutta fario populations in Switzerland. Here we examined (1) how PKD prevalence and pathology in young-of-the-year (YOY) brown trout relate to water temperature, (2) whether wild brown trout can completely recover from T. bryosalmonae-induced renal lesions and eliminate T. bryosalmonae over the winter months, and (3) whether this rate and/or extent of the recovery is influenced by concurrent infection. A longitudinal field study on a wild brown trout cohort was conducted over 16 mo. YOY and age 1+ fish were sampled from 7 different field sites with various temperature regimes, and monitored for infection with T. bryosalmonae and the nematode Raphidascaris acus. T. bryosamonae was detectable in brown trout YOY from all sampling sites, with similar renal pathology, independent of water temperature. During winter months, recovery was mainly influenced by the presence or absence of concurrent infection with R. acus larvae. While brown trout without R. acus regenerated completely, concurrently infected brown trout showed incomplete recovery, with chronic renal lesions and incomplete translocation of T. bryosalmonae from the renal interstitium into the tubular lumen. Water temperature seemed to influence complete excretion of T. bryosalmonae, with spores remaining in trout from summer-warm rivers, but absent in trout from summer-cool rivers. In the following summer months, we found PKD infections in 1+ brown trout from all investigated river sites. The pathological lesions indicated a re-infection rather than a proliferation of remaining T. bryosalmonae. However, disease prevalence in 1+ trout was lower than in YOY.

  1. [Plants regeneration from genetically transformed root and callus cultures of periwinkle Vinca minor L. and foxglove purple Digitalis purpurea L].

    Leshina, L G; Bulko, O V


    Plants regenerated from hairy roots and calluses of foxglove purple and periwinkle have been obtained. It was found that organogenesis in hairy root culture occurs spontaneously on hormone-free medium but with different efficiencies. The frequency of direct shoot formation from root cultures was up to 60% in Digitalis and 3.7% in Vinca. Addition of 1 mg/l BA, 0.1 mg/l NAA and 5% sucrose to B5 medium increased regenerative capacity of Vinca roots up to 19.1%. Regenerated plants showed morphological features typically seen in Ri-transgenic plants. They include growth and plagiotropism of the root system, increased shoot formation, changed leaf morphology and short internodes.

  2. A p53-based genetic tracing system to follow postnatal cardiomyocyte expansion in heart regeneration.

    Xiao, Qi; Zhang, Guoxin; Wang, Huijuan; Chen, Lai; Lu, Shuangshuang; Pan, Dejing; Liu, Geng; Yang, Zhongzhou


    In the field of heart regeneration, the proliferative potential of cardiomyocytes in postnatal mice is under intense investigation. However, solely relying on immunostaining of proliferation markers, the long-term proliferation dynamics and potential of the cardiomyocytes cannot be readily addressed. Previously, we found that a p53 promoter-driving reporter predominantly marked the proliferating lineages in mice. Here, we established a p53-based genetic tracing system to investigate postnatal cardiomyocyte proliferation and heart regeneration. By selectively tracing proliferative cardiomyocytes, a differential pattern of clonal expansion in p53(+) cardiac myocytes was revealed in neonatal, adolescent and adult stages. In addition, the percentage of p53(+) lineage cardiomyocytes increased continuously in the first month. Furthermore, these cells rapidly responded to heart injury and greatly contributed to the replenished myocardium. Therefore, this study reveals complex proliferating dynamics in postnatal cardiomyocytes and heart repair, and provides a novel genetic tracing strategy for studying postnatal cardiac turnover and regeneration. © 2017. Published by The Company of Biologists Ltd.

  3. Signals flowing from mature tissues to shoot apical meristem affect phyllotaxis in coniferous shoot.

    Beata Zagórska-Marek


    Full Text Available Axial homodromy in growing shoots of perennial plants with spiral phyllotaxis is the case when the chirality of phyllotactic pattern does not change in consecutive growth increments of the same axis. In conifers such as Picea or Abies this rule is strictly observed, except for the rare cases of discontinuous phyllotactic transitions. In Torreya, however, the chirality changes, at random, every year. The pattern of primordia packing, executed by vegetative shoot apical meristem (SAM, depends in Torreya on their identity. The primordia of bud scales are initiated in the decussate and those of needles in bijugate spiral pattern. The decussate, achiral i.e. neutral pattern always precedes the formation of new spiral pattern and thus facilitates random selection of its chiral configuration. Periodic change in organ identity cannot itself be responsible for the special behavior of Torreya, because in other conifers it also exists. There is, however, one important difference: in Torreya, when the initiation of bud scales begins at SAM, the distance between differentiated protoxylem and the initiation site gradually increases, while in other conifers it remains constant and small. In Torreya, at this phase of development, the rate of xylem differentiation and the rate of organogenesis become uncoupled. Closer anatomical examination shows that the decussate pattern in a bud scale zone develops slowly suggesting gradual decrease of the putative signal flowing acropetally from differentiated protoxylem, responsible for positioning of primordia. We hypothesize that in the absence of this signal SAM starts acting autonomously, distributing primordia according to their identity only. A constant presence of the signal in other conifers assures the continuation of the same phyllotactic pattern throughout the period of bud scale formation, despite the change in organ identity.

  4. Diamex solvent regeneration studies

    Nicol, C.; Cames, B.; Margot, L.; Ramain, L. [CEA/VALRHO - site de Marcoule, Dept. de Recherche en Retraitement et en Vitrification, DRRV, 30 - Marcoule (France)


    The CEA has undertaken the development of the DIAMEX process as the first step in the strategy aiming at recovering minor actinides which could then be transmuted or separately conditioned. The scientific feasibility of this process was demonstrated during counter current hot tests operated in 1993. Then experimental works were conducted, on one hand to optimise the extractant formula, on the other hand to improve the flowsheet. Reference extractant and flowsheet were then chosen, respectively in 1995 and 1996. The next step, still in progress, is the demonstration of the DIAMEX technical feasibility (in 2002); this means that the flowsheet should include solvent regeneration treatments. In this aim, degradation studies were performed to quantify main degradation products, and identify those which could be disturbing in the process. This paper deals with experimental studies performed with intend to propose a regeneration treatment, included in the flowsheet, so that the solvent could be recycled. It comprises: - Quantification of the main degradation products issued from radiolysis or hydrolysis, which are methyl octyl amine (MOA) and carboxylic acids; - Effects of these products on extracting and hydrodynamics performances of the process; - Study of methods able to remove mainly disturbing degradation products. Acidic scrubbing, which are performed in the scrubbing and stripping sections of the DIAMEX process, should allow the quantitative removal of methyl octyl amine. Then basic scrubbings, which were more especially studied, should eliminate at least 80% of carboxylic acids, and part of the cations remaining in the solvent. (authors)

  5. Nanobiomaterials for neural regeneration

    Nuan Chen; Lingling Tian; Liumin He; Seeram Ramakrishna


    Diseases and disorders associated with nervous system such as injuries by trauma and neurodegeneration are shown to be one of the most serious problems in medicine, requiring innovative strategies to trigger and enhance the nerve regeneration. Tissue engineering aims to provide a highly biomimetic environment by using a combination of cells, materials and suitable biological cues, by which the lost body part may be regenerated or even fully rebuilt. Electrospinning, being able to produce extracellular matrix (ECM)-like nanostructures with great lfexibility in design and choice of materials, have demonstrated their great po-tential for fabrication of nerve tissue engineered scaffolds. The review here begins with a brief description of the anatomy of native nervous system, which provides basic knowledge and ideas for the design of nerve tissue scaffolds, followed by ifve main parts in the design of electrospun nerve tissue engineered scaffolds including materials selection, structural design,in vitro bioreactor, functionalization and cellular support. Performances of biomimetic electrospun nanofibrous nerve implant devices are also reviewed. Finally, future directions for advanced electrospun nerve tissue engineered scaffolds are discussed.

  6. Four waves of hepatocyte proliferation linked with three waves of hepatic fat accumulation during partial hepatectomy-induced liver regeneration.

    Yuhong Zou

    Full Text Available Partial hepatectomy (PH triggers hepatocyte proliferation-mediated liver repair and is widely used to study the mechanisms governing liver regeneration in mice. However, the dynamics of the hepatocyte proliferative response to PH remain unclear. We found that PH-induced mouse liver regrowth was driven by four consecutive waves of hepatocyte replication. The first wave exhibited the highest magnitude followed by two moderate waves and one minor wave. Underlying this continuous hepatocyte replication was persistent activation of cell cycle components throughout the period of liver regeneration. Hepatocyte mitotic activity in the first three proliferative cycles showed a circadian rhythm manifested by three corresponding mitosis peaks, which were always observed at Zeitgeber time 0. The Bmal1-Clock/Wee1/Cdc2 pathway has been proposed by others to govern the circadian rhythm of hepatocyte mitosis during liver regeneration. However, we did not observe the correlations in the expression or phosphorylation of these proteins in regenerating livers. Notably, Bmal1 protein displayed frequent changes in hepatic distribution and cellular localization as the liver regrowth progressed. Further, three waves of hepatic fat accumulation occurred during hepatic regeneration. The first started before and lasted through the first round of hepatocyte proliferation, whereas the second and third occurred concomitantly with the second and third mitotic peaks, respectively.PH-induced liver regeneration consists of four continuous waves of hepatocyte proliferation coupled with three waves of hepatic fat accumulation. Bmal1, Wee1, and Cdc2 may not form a pathway regulating the circadian rhythm of hepatocyte mitosis during liver regeneration.

  7. Plant regeneration of non-toxic Jatropha curcas—impacts of plant growth regulators, source and type of explants

    Kumar, Nitish


    Jatropha curcas is an oil bearing species with multiple uses and considerable economic potential as a biofuel plant, however, oil and deoiled cake are toxic. A non-toxic variety of J. curcas is reported from Mexico. The present investigation explores the effects of different plant growth regulators (PGRs) viz. 6-benzyl aminopurine (BAP) or thidiazuron (TDZ) individually and in combination with indole-3-butyric acid (IBA), on regeneration from in vitro and field-grown mature leaf explants, in vitro and glasshouse-grown seedlings cotyledonary leaf explants of non-toxic J. curcas. In all the tested parameters maximum regeneration efficiency (81.07%) and the number of shoot buds per explants (20.17) was observed on 9.08 μM TDZ containing Murashige and Skoog’s (MS) medium from in vitro cotyledonary leaf explants. The regenerated shoot buds were transferred to MS medium containing 10 μM kinetin (Kn), 4.5 μM BAP and 5.5 μM α-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with 2.25 μM BAP and 8.5 μM IAA. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing different concentrations and combinations of IBA, IAA and NAA for four days followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg/l activated charcoal. The rooted plants could be established in soil with more than 90% survival rate.

  8. Shoot differentiation from protocorm callus cultures of Vanilla planifolia (Orchidaceae: proteomic and metabolic responses at early stage

    Payet Bertrand


    Full Text Available Abstract Background Vanilla planifolia is an important Orchid commercially cultivated for the production of natural vanilla flavour. Vanilla plants are conventionally propagated by stem cuttings and thus causing injury to the mother plants. Regeneration and in vitro mass multiplication are proposed as an alternative to minimize damage to mother plants. Because mass production of V. planifolia through indirect shoot differentiation from callus culture is rare and may be a successful use of in vitro techniques for producing somaclonal variants, we have established a novel protocol for the regeneration of vanilla plants and investigated the initial biochemical and molecular mechanisms that trigger shoot organogenesis from embryogenic/organogenic callus. Results For embryogenic callus induction, seeds obtained from 7-month-old green pods of V. planifolia were inoculated on MS basal medium (BM containing TDZ (0.5 mg l-1. Germination of unorganized mass callus such as protocorm -like structure (PLS arising from each seed has been observed. The primary embryogenic calli have been formed after transferring on BM containing IAA (0.5 mg l-1 and TDZ (0.5 mg l-1. These calli were maintained by subculturing on BM containing IAA (0.5 mg l-1 and TDZ (0.3 mg l-1 during 6 months and formed embryogenic/organogenic calli. Histological analysis showed that shoot organogenesis was induced between 15 and 20 days after embryogenic/organogenic calli were transferred onto MS basal medium with NAA (0.5 mg l-1. By associating proteomics and metabolomics analyses, the biochemical and molecular markers responsible for shoot induction have been studied in 15-day-old calli at the stage where no differentiating part was visible on organogenic calli. Two-dimensional electrophoresis followed by matrix-assisted laser desorption ionization time-of-flight-tandem mass spectrometry (MALDI-TOF-TOF-MS analysis revealed that 15 protein spots are significantly expressed (P Conclusion The

  9. Effect of antibiotic cefotaxime and kanamycin on callus formation and plantlet regeneration from leaves and callus of mangosteen

    Rugpheug, R.


    Full Text Available In order to get rid of contamination from Agrobacterium tumefaciens, the bacterium employed in gene transformation, various kinds and concentrations of antibiotics were added singly or in combinations. In this investigation, concentrations of cefotaxime and kanamycin were examined for callus formation and regenerability from leaves and callus. The results showed that cefotaxime at the concentration of up to 300 mg/l gave a non-significant difference in callus formation. In the case of direct shoot bud formation, concentration over 100 mg/l drastically reduced percentage of leaf-forming shoot buds. The calli which were cultured continuously in 300 mg/l cefotaxime-containing medium for 6 passages gave callus forming shoot buds of 35%. Higher concentration of cefotaxime drastically decreased bud formation. In the case of kanamycin, callus could be induced and maintained in the medium supplemented with a lower concentration than cefotaxime. However, the callus could not be maintained after 3 subculturings.

  10. Progesterone and peripheral nerve regeneration

    Fei Fan; Haichao Li; Yuwei Wang; Yanglin Zheng; Lianjun Jia; Zhihui Wang


    OBJECTIVE: To explore the effect of progesterone on peripheral nerve regeneration.DATA SOURCES: An online search of Medline and OVID databases was under taken to identify articles about progesterone and peripheral nerve regeneration published in English between January 1990 and June 2004 by using the keywords of "peripheral nerve, injury, progesterone, regeneration".STUDY SELECTION: The data were primarily screened, those correlated with progesterone and peripheral nerve regeneration were involved, and their original articles were further searched, the repetitive studies or reviews were excluded.DATA EXTRACTION: Totally 59 articles about progesterone and peripheral nerve regeneration were collected, and 26 of them were involved, the other 33 excluded ones were the repetitive studies or reviews.DATA SYNTHESIS: Recent researches found that certain amount of progesterone could be synthetized in peripheral nervous system, and the expression of progesterone receptor could be found in sensory neurons and Schwann cells. After combined with the receptor, endogenous and exogenous progesterone can accelerate the formation of peripheral nerve myelin sheath, also promote the axonal regeneration.CONCLUSION: Progesterone plays a role in protecting neurons, increasing the sensitivity of nerve tissue to nerve growth factor, and accelerating regeneration of nerve in peripheral nerve regeneration, which provides theoretical references for the treatment of demyelinated disease and nerve injury, as well as the prevention of neuroma, especially that the in vivo level of progesterone should be considered for the elderly people accompanied by neuropathy and patients with congenital luteal phase defect, which is of positive significance in guiding the treatment.

  11. Molecular approach to echinoderm regeneration.

    Thorndyke, M C; Chen, W C; Beesley, P W; Patruno, M


    Until very recently echinoderm regeneration research and indeed echinoderm research in general has suffered because of the lack of critical mass. In terms of molecular studies of regeneration, echinoderms in particular have lagged behind other groups in this respect. This is in sharp contrast to the major advances achieved with molecular and genetic techniques in the study of embryonic development in echinoderms. The aim of our studies has been to identify genes involved in the process of regeneration and in particular neural regeneration in different echinoderm species. Our survey included the asteroid Asterias rubens and provided evidence for the expression of Hox gene homologues in regenerating radial nerve cords. Present evidence suggests: 1) ArHox1 expression is maintained in intact radial nerve cord and may be upregulated during regeneration. 2) ArHox1 expression may contribute to the dedifferentiation and/or cell proliferation process during epimorphic regeneration. From the crinoid Antedon bifida, we have been successful in cloning a fragment of a BMP2/4 homologue (AnBMP2/4) and analysing its expression during arm regeneration. Here, we discuss the importance of this family of growth factors in several regulatory spheres, including maintaining the identity of pluripotent blastemal cells or as a classic skeletal morphogenic regulator. There is clearly substantial scope for future echinoderm research in the area of molecular biology and certain aspects are discussed in this review.

  12. In vitro multiplication of Swietenia macrophylla King (Meliaceae from juvenile shoots

    Eliane de Souza Schottz


    Full Text Available Big-leaf mahogany (Swietenia macrophylla King is an important species for timber production that is considered the most valuable in the world. For this reason its exploitation is indiscriminate and leads this species to the risk of extinction. Moreover, mahogany is difficult to regenerate naturally and, when used in reforestation programs, plants are severely damaged by the shoot-borer (Hypsipyla grandella Zellar. This work aimed at developing the multiplication stage of micropropagation of Swietenia macrophylla King using juvenile material. After desinfestation, seeds were germinated in MS solid culture medium. Shoot formation from seeds occurred during five months, giving 5.54 nodal segments per seed. These explants were excised, each containing one axillary bud, and transferred on multiplication media. Four experiments with cytokinins were conducted, using media supplemented with 6-benzylaminopurine (BAP (2.5 to 50.0 μM, 2- isopentenyladenine (2-iP (0; 1.1 to 8.8 μM, combinations of BAP (0; 2.5 to 50.0 μM and 2-iP (2.2 μM. For the first treatments the basal culture medium was MS medium and in the last one MS and QL media were used in separate experiments. When BAP was tested alone, the maximum point of multiplication rate average was obtained on medium containing 23.61 μM, while 2-iP did not induce bud multiplication. On QL culture medium supplemented with the combinations of BAP (0; 2.5; 5.0; 10.0 e 20.0 μM and 2-iP (2.2 μM, there was no multiplication. The maximum point of multiplication rate average was 5.7 μM, obtained when the MS culture medium was supplemented with 18.51 μM BAP and 2.2 μM 2-iP.

  13. Micropropagation and validation of genetic and biochemical fidelity among regenerants of Nothapodytes nimmoniana (Graham) Mabb. employing ISSR markers and HPLC.

    Prakash, Lokesh; Middha, Sushil Kumar; Mohanty, Sudipta Kumar; Swamy, Mallappa Kumara


    An in vitro protocol has been established for clonal propagation of Nothapodytes nimmoniana which is an important source of Camptothecin (CPT). Elite source was identified based on the chemical potency to accumulate the optimum level of CPT. Different types and concentrations of plant growth regulators were used to study their effect on inducing multiple shoots from the explants regenerated from embryos of N. nimmoniana. Of these, a combination of N6-benzyladenine (0.2 mg L(-1)) and Indole-3-butyric acid (IBA) (0.1 mg L(-1)) proved optimum for differentiating multiple shoots in 90.6 % of the cultures with an average of 10.24 shoots per explant obtained within 8 weeks of inoculation. Nearly, 92 % of the excised in vitro shoots rooted on half strength Murashige and Skoog (MS) medium containing 0.05 % activated charcoal, supplemented with 1-naphthaleneacetic acid and IBA at 0.1 mg L(-1) each. The micropropagated plants were evaluated for their genetic fidelity by employing inter simple sequence repeats (ISSR) markers. Ten individuals, randomly chosen from a population of 145 regenerants, were compared with the donor plant. The regenerated plants were also evaluated for their chemical potency using high-performance liquid chromatography (HPLC) analysis of CPT content. The true-to-type nature of the micropropagated plants was confirmed based on their monomorphic banding profiles with that of the mother plants using ISSR markers. Besides, HPLC evaluation of the CPT content confirmed the existence of chemical uniformity among the regenerated plants and the elite mother plant.

  14. The Basis of Muscle Regeneration

    Antonio Musarò


    Full Text Available Muscle regeneration recapitulates many aspects of embryonic myogenesis and is an important homeostatic process of the adult skeletal muscle, which, after development, retains the capacity to regenerate in response to appropriate stimuli, activating the muscle compartment of stem cells, namely, satellite cells, as well as other precursor cells. Moreover, significant evidence suggests that while stem cells represent an important determinant for tissue regeneration, a “qualified” environment is necessary to guarantee and achieve functional results. It is therefore plausible that the loss of control over these cell fate decisions could lead to a pathological transdifferentiation, leading to pathologic defects in the regenerative process. This review provides an overview about the general aspects of muscle development and discusses the cellular and molecular aspects that characterize the five interrelated and time-dependent phases of muscle regeneration, namely, degeneration, inflammation, regeneration, remodeling, and maturation/functional repair.

  15. Acoustic field modulation in regenerators

    Hu, J. Y.; Wang, W.; Luo, E. C.; Chen, Y. Y.


    The regenerator is a key component that transfers energy between heat and work. The conversion efficiency is significantly influenced by the acoustic field in the regenerator. Much effort has been spent to quantitatively determine this influence, but few comprehensive experimental verifications have been performed because of difficulties in modulating and measuring the acoustic field. In this paper, a method requiring two compressors is introduced and theoretically investigated that achieves acoustic field modulation in the regenerator. One compressor outputs the acoustic power for the regenerator; the other acts as a phase shifter. A RC load dissipates the acoustic power out of both the regenerator and the latter compressor. The acoustic field can be modulated by adjusting the current in the two compressors and opening the RC load. The acoustic field is measured with pressure sensors instead of flow-field imaging equipment, thereby greatly simplifying the experiment.

  16. A Case of Proliferative Retinopathy Complicated with Tuberous Sclerosis Treated by Vitreous Surgery

    Nemoto, Emika; Morishita, Seita; Akashi, Mari; Kohmoto, Ryohsuke; Fukumoto, Masanori; Suzuki, Hiroyuki; Kobayashi, Takatoshi; Kida, Teruyo; Sugasawa, Jun; Ikeda, Tsunehiko


    We report a case of proliferative retinopathy complicated with retinal hamartoma in a tuberous sclerosis patient. This study involved a 16-year-old female patient who was diagnosed as having tuberous sclerosis at birth. Ophthalmic examination revealed retinal hamartoma surrounding the optic disc in both eyes. Vitreous surgery involving a vitrectomy and resection of the proliferative membranes was performed for proliferative retinopathy in her right eye. Postoperative fundus findings showed improvement and decreased exudative changes. The proliferative and exudative changes appeared to be due to the retinal hamartoma, and vitreous surgery proved effective in this case. PMID:28101046

  17. Experiment "Regeneration" Performed Aboard the Russian Spacecraft Foton-M2 in 2005

    Grigoryan, Elonora; Almeida, Eduardo; Domaratskaya, Elena; Poplinskaya, Valentina; Aleinikova, Karina; Tairbekov, Murad; Mitashov, Victor


    The experiments on the newts performed earlier aboard Russian biosate llites showed that the rate of lens and tail regeneration in space wa s greater than on the ground. In parallel it was found that the numbe r of cells in S-phase was greater in space-flown animals than in the ground controls. However, it was unclear whether cell proliferation stimulation was induced by micro-g per se. Molecular mechanisms under lying the change also remained obscure. These issues were addressed b y the joint Russian-American experiment "Regeneration" flown on Foton -M2 in 2005. The method for in-flight delivering DNA precursor BrdU was developed. The experiment showed that during the flight the numbe r of S-phase cells in the regenerating eyes and tails increased. Thes e data together with those obtained earlier suggest that cell prolife ration increases in response to the effects of both micro-g and 1-g a fter return to Earth. The expression of bFGF in regenerating tissues of "flown" newts and ground controls was examined using immuno-histo chemistry. Obtained results suggest that this growth factor is a part icipant of the promotional effect of space flight upon cell prolifera tion in lens and tail regenerates.

  18. dlx and sp6-9 Control optic cup regeneration in a prototypic eye.

    Sylvain W Lapan


    Full Text Available Optic cups are a structural feature of diverse eyes, from simple pit eyes to camera eyes of vertebrates and cephalopods. We used the planarian prototypic eye as a model to study the genetic control of optic cup formation and regeneration. We identified two genes encoding transcription factors, sp6-9 and dlx, that were expressed in the eye specifically in the optic cup and not the photoreceptor neurons. RNAi of these genes prevented formation of visible optic cups during regeneration. Planarian regeneration requires an adult proliferative cell population with stem cell-like properties called the neoblasts. We found that optic cup formation occurred only after migration of progressively differentiating progenitor cells from the neoblast population. The eye regeneration defect caused by dlx and sp6-9 RNAi can be explained by a failure to generate these early optic cup progenitors. Dlx and Sp6-9 genes function as a module during the development of diverse animal appendages, including vertebrate and insect limbs. Our work reveals a novel function for this gene pair in the development of a fundamental eye component, and it utilizes these genes to demonstrate a mechanism for total organ regeneration in which extensive cell movement separates new cell specification from organ morphogenesis.

  19. Down-regulation of the beacon gene expression in the regenerating rat adrenal cortex.

    Ziolkowska, Agnieszka; Rucinski, Marcin; Tyczewska, Marianna; Belloni, Anna Sandra; Nowak, Magdalena; Nussdorfer, Gastone G; Malendowicz, Ludwik K


    Beacon, a hypothalamic peptide involved in the regulation of food intake, has been recently shown to be expressed in the adrenal cortex, and to inhibit its secretion and growth. To further characterize the role of beacon in the control of adrenal growth, we investigated the level of beacon gene expression in the regenerating rat adrenal cortex. Conventional reverse transcription-polymerase chain reaction (PCR) and immunocytochemistry demonstrated the expression of beacon mRNA and protein in the adrenals at both days 5 and 8 of regeneration after enucleation and contralateral adrenalectomy. Semiquantitative real time-PCR revealed a net down-regulation of beacon mRNA in the regenerating glands, as compared to the intact adrenal cortex of sham-operated animals. Beacon gene expression was higher at day 8 than at day 5 of regeneration. Mitotic index, as assayed by the stachmokinetic method with vincristin, was negligible in the intact adrenal, but greatly elevated in regenerating gland, with a higher index found at day 5 than at day 8 after surgery. Taken together our findings indicate that the level of beacon gene expression is inversely correlated with the proliferative activity of adrenocortical cells, and suggest that beacon might act as an endogenous inhibitor of adrenocortical growth in the rat.

  20. Difference in Selenium Accumulation in Shoots of Two Rice Cultivars

    ZHANG Lian-He; SHI Wei-Ming; WANG Xiao-Chang


    Two japonica rice (Oryza sativa L.) cultivars, Xiushui 48 and S. Andrea, differing in their ability to accumulate Se in the grain (as high as a three-fold difference), were compared for selenium (Se) accumulation in their shoots when their growth media was supplied with different forms of Se. Results indicated that when treated with 0.25μmol L-1 Na2SeO3,Xiushui 48 accumulation of Se in the shoots was significantly more rapid (P ≤ 0.05) than S. Andrea, probably because of greater Se uptake and transport in Xiushui 48. Xiushui 48 rice seedlings had a higher shoot-Se accumulation rate and absorbed selenocysteine (Se-Cys) more rapidly than S. Andrea seedlings. However, when treated with Se as 0.25 μmol L-1 selenomethionine (Se-Met), the S. Andrea seedlings' accumulation rate was significantly greater (P ≤ 0.05) than that of Xiushui 48. Possibly, the high Se accumulation rate of Xiushui 48 seedling shoots compared to S. Andrea shoots was the result of a higher capacity of Xiushui 48 to transform selenite to organic Se compounds and a higher selenite uptake rate.

  1. Branching Shoots and Spikes from Lateral Meristems in Bread Wheat.

    Ying Wang

    Full Text Available Wheat grain yield consists of three components: spikes per plant, grains per spike (i.e. head or ear, and grain weight; and the grains per spike can be dissected into two subcomponents: spikelets per spike and grains per spikelet. An increase in any of these components will directly contribute to grain yield. Wheat morphology biology tells that a wheat plant has no lateral meristem that forms any branching shoot or spike. In this study, we report two novel shoot and spike traits that were produced from lateral meristems in bread wheat. One is supernumerary shoot that was developed from an axillary bud at the axil of leaves on the elongated internodes of the main stem. The other is supernumerary spike that was generated from a spikelet meristem on a spike. In addition, supernumerary spikelets were generated on the same rachis node of the spike in the plant that had supernumerary shoot and spikes. All of these supernumerary shoots/spikes/spikelets found in the super wheat plants produced normal fertility and seeds, displaying huge yield potential in bread wheat.

  2. Ontogeny of the Maize Shoot Apical Meristem[W][OA

    Takacs, Elizabeth M.; Li, Jie; Du, Chuanlong; Ponnala, Lalit; Janick-Buckner, Diane; Yu, Jianming; Muehlbauer, Gary J.; Schnable, Patrick S.; Timmermans, Marja C.P.; Sun, Qi; Nettleton, Dan; Scanlon, Michael J.


    The maize (Zea mays) shoot apical meristem (SAM) arises early in embryogenesis and functions during stem cell maintenance and organogenesis to generate all the aboveground organs of the plant. Despite its integral role in maize shoot development, little is known about the molecular mechanisms of SAM initiation. Laser microdissection of apical domains from developing maize embryos and seedlings was combined with RNA sequencing for transcriptomic analyses of SAM ontogeny. Molecular markers of key events during maize embryogenesis are described, and comprehensive transcriptional data from six stages in maize shoot development are generated. Transcriptomic profiling before and after SAM initiation indicates that organogenesis precedes stem cell maintenance in maize; analyses of the first three lateral organs elaborated from maize embryos provides insight into their homology and to the identity of the single maize cotyledon. Compared with the newly initiated SAM, the mature SAM is enriched for transcripts that function in transcriptional regulation, hormonal signaling, and transport. Comparisons of shoot meristems initiating juvenile leaves, adult leaves, and husk leaves illustrate differences in phase-specific (juvenile versus adult) and meristem-specific (SAM versus lateral meristem) transcript accumulation during maize shoot development. This study provides insight into the molecular genetics of SAM initiation and function in maize. PMID:22911570


    LI Hong-mei; LI Xing-feng; GAO Ju-rong; WANG Hong-gang


    An efficient plant regeneration system was developed from the immature embryos of Triticum aestivum L. - Thinopyrum intermedium alien disomic addition lines, which resistant to powdery mildew. The protocol was based on a series of experiments involving the callus induction and differentiation. The experiment studied the effects of embryo size on callus induction and differentiation of the immature embryos. We found that the embryo size is critical for the establishment of embryogenic callus. Immature embryos (0.8~1.5 mm) showed high ability to produce embryogenic callus capable of regenerating green plants. The medium Murashige and Skoog's (MS) added with 2mg/L 2, 4-dichlorophenoxyacetic acid (2, 4-D) gave the best embryogenic callus induction, maintenance and regeneration. The embryogenic callus maintained high regeneration during six subcultures in the callus induction medium. Suitable time of partial desiccation could effectively improve the regeneration capacity of the callus cultured for 3~4 month.Bud green spot and root green spot were observed during the differentiation of callus and the difference between them was described. Regenerated shoots were rooted on half-strength MS medium containing 0.2 mg/L Naphthalene acetic acid (NAA). Plants were successfully transferred to soil and grew well. This efficient plant regeneration system provides a foundation for the study of somaclonal variation of Triticum aestivum L. - Thinopyrum intermedium alien disomic addition lines.

  4. Factors affecting in vitro plant regeneration of the critically endangered Mediterranean knapweed ( Centaurea tchihatcheffii Fisch et. Mey)

    Ozel, Cigdem Alev; Khawar, Khalid Mahmood; Mirici, Semra; Ozcan, Sebahattin; Arslan, Orhan


    Habitat destruction has resulted in the extinction of many plant species from the earth, and many more face extinction. Likely, the annual endemic Mediterranean knapweed ( Centaurea tchihatcheffii) growing in the Golbasi district of Ankara, Turkey is facing extinction and needs urgent conservation. Plant tissue culture, a potentially useful technique for ex situ multiplication, was used for the restoration of this ill-fated plant through seed germination, micropropagation from stem nodes, and adventitious shoot regeneration from immature zygotic embryos. The seeds were highly dormant and very difficult to germinate. No results were obtained from the micropropagation of stem nodes. However, immature zygotic embryos showed the highest adventitious shoot regeneration on Murashige and Skoog (MS) medium, containing 1 mg l-1 kinetin and 0.25 mg l-1 NAA. Regenerated shoots were best rooted on MS medium containing 1 mg l-1 IBA and transferred to the greenhouse for flowering and seed set. As such, the present work is the first record of in vitro propagation of critically endangered C. tchihatcheffii, using immature zygotic embryos, and is a step forward towards conservation of this indigenous species.

  5. Planarian regeneration under micro- and hyper-gravity simulated contexts

    Auletta, Gennaro; Van Loon, ing.. Jack J. W. A.; Adell, Teresa; Salo, Emili

    Planarians are non-parasitic flatworms of the Turbellaria class, some of which show the striking ability to regenerate any part of their body, even the head, in few days. Planarians are common to many parts of the world, living in both saltwater and freshwater, as well as in terrestrial areas. Due to their plasticity Planarians have been a classical model for the study of the mechanisms of regeneration. Currently, their cheap and easy maintenance, as well as the establishment of robust genetic tools, have converted them into an essential system in the field of stem cells and regenerative medicine. The aim of our project is to study the effect that micro- and hyper- gravity could exert during the process of planarians regeneration. The reason for planarians extreme regenerative capability is the maintenance until adulthood of a population of totipotent stem cells as well as the continuous activation of the cell-cell communication molecular pathways. Our prediction is that the alteration of the forces could affect planarians regeneration at different levels: 1) To regenerate, planarians must activate both proliferative and apoptotic responses, in order to create new tissue and to remodel the pre-existing one, respectively. Both cellular processes have been reported to be altered in several models under differential gravitational forces; 2) In planarians, the main intercellular signalling pathways (Wnt, TGFb, BMP, Hh, EGF) must control the process of differentiation and determination of each cell. For instances, it has been demonstrated that the differential activity of the wnt/beta-catenin pathway specifies the posterior (tail) versus the anterior (head) identity. Those pathways rely on the distance that secreted molecules (morphogens) are able to reach. Either this mechanism consist in a passive diffusion or an active transport through phyllopodia, it could sense the magnitude of the gravitational force; 3) The epidermis of planarians is covered by cilia, which beat

  6. Polyphenols with Anti-Proliferative Activities from Penthorum Chinense Pursh

    Doudou Huang


    Full Text Available Two new polyphenols, penthorumin C (1 and 2,6-dihydroxyacetophenone-4-O- [4ꞌ,6ꞌ-(S-hexahydroxydiphenoyl]-β-D-glucose (2, along with four known polyphenolic acids, pinocembrin-7-O-[4ꞌꞌ,6ꞌꞌ-hexahydroxydiphenoyl]-β-D-glucose(3, pinocembrin-7-O-[3ꞌꞌ-O- galloyl- 4ꞌꞌ,6ꞌꞌ-hexahydroxydiphenoyl]-β-D-glucose (4, thonningianin A (5, and thonningianin B (6 were isolated from Penthourm chinense. All compounds were evaluated for their anti-proliferative activity in HSC-T6 cells, and 2 and 5 showed significant activity, with IC50 values of 12.7 and 19.2 μM, respectively.

  7. Early pathogenesis in porcine proliferative enteropathy caused by Lawsonia intracellularis

    Boutrup, Torsten Snogdal; Boesen, H. T.; Boye, Mette


    The intestinal bacterium Lawsonia intracellularis, the cause of proliferative enteropathy (PE) in pigs, is believed to infect mitotically active epithelial cells of the intestinal crypts and then multiply and spread in these cells as they divide. Further spread of infection is thought to occur...... by shedding of bacteria from infected crypts followed by infection of new crypts. The early stages of the pathogenesis of PE, from 0 to 48 hours post-infection (hpi), have not been studied in vivo. In the present study pigs were inoculated with L. intracellularis and killed from 12 hpi to 5 days post...... enterocytes. Furthermore, early invasion of the intestinal connective tissue was observed; with the presence of single bacteria in the lamina propria 12 hpi, and with a further spread of bacteria in the lamina propria observed at 5 dpi, suggesting an active role for the lamina propria in the course...

  8. Strategic planning ensures surgical success in cases of proliferative vitreoretinopathy.

    Lakhanpal, R Ross; Hariprasad, Seenu M


    For this Practical Retina column, Dr. Ross Lakhanpal from Baltimore was asked to comment on the current state of thinking and management options for proliferative vitreoretinopathy (PVR) after retinal detachment (RD) surgery.We are all aware that PVR continues to be an important cause of recurrent RD after successful repair. This feared complication has been reported to occur in up to 8% of patients after undergoing RD repair. Despite the historic progress made in managing various vitreoretinal diseases over the past decade, most retina specialists will agree that an unmet need remains in this landscape. Fortunately, advances in various surgical technologies such as instrumentation, lighting, and visualization have improved the outcomes after PVR management.Dr. Lakhanpal discusses causes of PVR, management goals, surgical techniques, and pearls to avoid complications after managing PVR. His experience working in an urban tertiary surgical retina practice enables him to offer insights that will be highly valued by our community.

  9. [Proliferative verrucous leukoplakia: Three cases and literature review].

    Ottavioli, A; Campana, F; Catherine, J-H; Massereau, E; Del Grande, J; Ordioni, U


    The aim of this study was to collect epidemiological, aetiopathogenic, clinical, histological and therapeutic data concerning proliferative verrucous leucoplakia (PVL) and to report three new cases. A literature review performed using the Medline database enabled us to collate 39 studies involving 607 cases. Three new cases were added. PVL is a rare disease characterized by extensive and multifocal oral leucoplakic lesions. Its histological pattern depends on the stage of the disease: hyperkeratosis, verrucous hyperplasia, verrucous carcinoma and squamous cell carcinoma. The aetiopathogenesis of PVL is poorly understood and there is no clear consensus concerning therapy. Malignant transformation occurs in over 50 % of cases. Diagnosis of PVL is difficult because of the presenting signs, which can be mistaken for those of other diseases. Management may be complicated and long-term follow-up is essential. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  10. Analysis and Enhancements of a Prolific Macroscopic Model of Epilepsy

    Christopher Fietkiewicz


    Full Text Available Macroscopic models of epilepsy can deliver surprisingly realistic EEG simulations. In the present study, a prolific series of models is evaluated with regard to theoretical and computational concerns, and enhancements are developed. Specifically, we analyze three aspects of the models: (1 Using dynamical systems analysis, we demonstrate and explain the presence of direct current potentials in the simulated EEG that were previously undocumented. (2 We explain how the system was not ideally formulated for numerical integration of stochastic differential equations. A reformulated system is developed to support proper methodology. (3 We explain an unreported contradiction in the published model specification regarding the use of a mathematical reduction method. We then use the method to reduce the number of equations and further improve the computational efficiency. The intent of our critique is to enhance the evolution of macroscopic modeling of epilepsy and assist others who wish to explore this exciting class of models further.

  11. [Proliferative granulomatous arachnoiditis: an infrequent form of tuberculous myeloradioculopathy].

    Amorín Díaz, M; Calleja Puerta, S; Jiménez-Blanco, L; Astudillo, A; Fernández, J M; Lahoz, C H


    Proliferative granulomatous arachnoiditis is an infrequent manifestation of central nervous system tuberculosis. The mortality rate is 30%, and there are functional sequels in almost all patients. We present the case of a 22-year-old woman, immunocompetent that suffered form tuberculous radiculo-myelopathy with fatal evolution, which allowed us to confront neuroimaging and neuropathological findings. Although serial MR imaging illustrated evolution of lesions, autopsy revealed more extensive lesions that those observed in neuroimaging studies. The characteristic pathological lesion was an intradural inflammatory exudate with a global medullar necrosis. Even through duration of medical treatment is still discussed, early diagnosis, complete antituberculous drug regimen and prolonged corticosteroid therapy are essential to avoid fatal evolution as occurred in this case.

  12. β-catenin/Wnt signaling controls progenitor fate in the developing and regenerating zebrafish retina

    Meyers Jason R


    Full Text Available Abstract Background The zebrafish retina maintains two populations of stem cells: first, the germinal zone or ciliary marginal zone (CMZ contains multipotent retinal progenitors that add cells to the retinal periphery as the fish continue to grow; second, radial glia (Müller cells occasionally divide asymmetrically to generate committed progenitors that differentiate into rod photoreceptors, which are added interstitially throughout the retina with growth. Retinal injury stimulates Müller glia to dedifferentiate, re-enter the cell cycle, and generate multipotent retinal progenitors similar to those in the CMZ to replace missing neurons. The specific signals that maintain these two distinct populations of endogenous retinal stem cells are not understood. Results We used genetic and pharmacological manipulation of the β-catenin/Wnt signaling pathway to show that it is required to maintain proliferation in the CMZ and that hyperstimulation of β-catenin/Wnt signaling inhibits normal retinal differentiation and expands the population of proliferative retinal progenitors. To test whether similar effects occur during regeneration, we developed a method for making rapid, selective photoreceptor ablations in larval zebrafish with intense light. We found that dephosphorylated β-catenin accumulates in Müller glia as they re-enter the cell cycle following injury, but not in Müller glia that remain quiescent. Activation of Wnt signaling is required for regenerative proliferation, and hyperstimulation results in loss of Müller glia from the INL as all proliferative cells move into the ONL. Conclusions β-catenin/Wnt signaling is thus required for the maintenance of retinal progenitors during both initial development and lesion-induced regeneration, and is sufficient to prevent differentiation of those progenitors and maintain them in a proliferative state. This suggests that the β-catenin/Wnt cascade is part of the shared molecular circuitry that

  13. Stimulative Effects of Low Intensity He-Ne Laser Irradiation on the Proliferative Potential and Cell-Cycle Progression of Myoblasts in Culture

    Cui-Ping Zhang


    Full Text Available Low intensity laser irradiation (LILI was found to promote the regeneration of skeletal muscle in vivo but the cellular mechanisms are not fully understood. Myoblasts, normally quiescent and inactivated in adult skeletal muscle, are a type of myogenic progenitor cells and considered as the major candidates responsible for muscle regeneration. The aim of the present study was to study the effect of LILI on the growth potential and cell-cycle progression of the cultured myoblasts. Primary myoblasts isolated from rat hind legs were cultured in nutrient-deficient medium for 36 hours and then irradiated by helium-neon laser at a certain energy density. Immunohistochemical and flow cytometric analysis revealed that laser irradiation could increase the expression of cellular proliferation marker and the amount of cell subpopulations in the proliferative phase as compared with the nonirradiated control group. Meanwhile, the expressions of cell-cycle regulatory proteins in the laser-treated myoblasts were markedly upregulated as compared to the unirradiated cells, indicating that LILI could promote the reentry of quiescent myoblasts into the cell division cycle. These results suggest that LILI at certain fluences could promote their proliferation, thus contributing to the skeletal muscle regeneration following trauma and myopathic diseases.

  14. Clinical significance of proliferative inflammatory atrophy in prostate biopsy.

    Celma, A; Servián, P; Planas, J; Placer, J; Quilez, M T; Arbós, M A; de Torres, I; Morote, J


    Proliferative inflammatory atrophy (PIA) is a frequently observed lesion in prostate biopsies and some authors have postulated its involvement in prostate carcinogenesis. However, the mechanisms that would permit its neoplastic transformation and the clinical significance of its finding in a prostate biopsy is currently not well known. To analyze the characteristics of the PIA lesion, its possible role in prostate carcinogenesis and its relation with the tumor aggressiveness. A systematic review was made of the literature in PubMed with the terms «proliferative inflammatory atrophy» or «PIA» and «prostate.» The most important findings are summarized in accordance with the study objective. PIA seems to be involved in prostate carcinogenesis. This hypothesis is based on its frequent association to cancer lesions (CaP) and on some genetic alterations that are common to the high grade prostatic intraepithelial neoplasia (HGPIN) and to the CaP, fundamentally deficit in GSTP1 expression and overexpression of AGR2. Currently, there are no epidemiological studies that evaluate the incidence of PIA or its association with HGPIN and CaP. Only one study, carried out by our group, has determined the global incidence of PIA in 30% of the prostate biopsies, a lower association to CaP than the HGPIN lesion and an association between PIA and tumors of lower and insignificant grade. PIA shares genetic alterations with HGPIN and CaP. Currently, there is no epidemiologic evidence to consider that the PIA is associated to a greater incidence of CaP and the genetic and epidemiological data available suggest its association to not very aggressive tumors. Copyright © 2013 AEU. Published by Elsevier Espana. All rights reserved.

  15. Automated detection of proliferative retinopathy in clinical practice

    Audrey Karperien


    Full Text Available Audrey Karperien1, Herbert F Jelinek1,2, Jorge JG Leandro3, João VB Soares3, Roberto M Cesar Jr3, Alan Luckie41School of Community Health, Charles Sturt University, Albury, Australia; 2Centre for Research in Complex Systems, Charles Sturt University, Albury, Australia; 3Creative Vision Research Group, Department of Computer Science, IME – University of São Paulo, Brazil; 4Albury Eye Clinic, Albury, AustraliaAbstract: Timely intervention for diabetic retinopathy (DR lessens the possibility of blindness and can save considerable costs to health systems. To ensure that interventions are timely and effective requires methods of screening and monitoring pathological changes, including assessing outcomes. Fractal analysis, one method that has been studied for assessing DR, is potentially relevant in today’s world of telemedicine because it provides objective indices from digital images of complex patterns such as are seen in retinal vasculature, which is affected in DR. We introduce here a protocol to distinguish between nonproliferative (NPDR and proliferative (PDR changes in retinal vasculature using a fractal analysis method known as local connected dimension (Dconn analysis. The major finding is that compared to other fractal analysis methods, Dconn analysis better differentiates NPDR from PDR (p = 0.05. In addition, we are the first to show that fractal analysis can be used to differentiate between NPDR and PDR using automated vessel identification. Overall, our results suggest this protocol can complement existing methods by including an automated and objective measure obtainable at a lower level of expertise that experts can then use in screening for and monitoring DR.Keywords: diabetes, proliferative retinopathy, automated clinical assessment, fractal dimension, complex systems

  16. Tamponade in surgery for retinal detachment associated with proliferative vitreoretinopathy

    Schwartz, Stephen G; Flynn, Harry W; Lee, Wen-Hsiang; Wang, Xue


    Background Retinal detachment (RD) with proliferative vitreoretinopathy (PVR) often requires surgery to restore normal anatomy and to stabilize or improve vision. PVR usually occurs in association with recurrent RD (that is, after initial retinal re-attachment surgery) but occasionally may be associated with primary RD. Either way, a tamponade agent (gas or silicone oil) is needed during surgery to reduce the rate of postoperative recurrent RD. Objectives The objective of this review was to assess the relative safety and effectiveness of various tamponade agents used with surgery for retinal detachment (RD) complicated by proliferative vitreoretinopathy (PVR). Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 5), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to June 2013), EMBASE (January 1980 to June 2013), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to June 2013), the metaRegister of Controlled Trials (mRCT) (, ( and the WHO International Clinical Trials Registry Platform (ICTRP) ( We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 26 June 2013. Selection criteria We included randomized controlled trials (RCTs) of participants undergoing surgery for RD associated with PVR that compared various tamponade agents. Data collection and analysis Two review authors screened the search results independently. We used the standard methodological procedures expected by The Cochrane Collaboration. PMID:24532038

  17. Characterization and functionality of proliferative human Sertoli cells.

    Chui, Kitty; Trivedi, Alpa; Cheng, C Yan; Cherbavaz, Diana B; Dazin, Paul F; Huynh, Ai Lam Thu; Mitchell, James B; Rabinovich, Gabriel A; Noble-Haeusslein, Linda J; John, Constance M


    It has long been thought that mammalian Sertoli cells are terminally differentiated and nondividing postpuberty. For most previous in vitro studies immature rodent testes have been the source of Sertoli cells and these have shown little proliferative ability when cultured. We have isolated and characterized Sertoli cells from human cadaveric testes from seven donors ranging from 12 to 36 years of age. The cells proliferated readily in vitro under the optimized conditions used with a doubling time of approximately 4 days. Nuclear 5-ethynyl-2'-deoxyuridine (EdU) incorporation confirmed that dividing cells represented the majority of the population. Classical Sertoli cell ultrastructural features, lipid droplet accumulation, and immunoexpression of GATA-4, Sox9, and the FSH receptor (FSHr) were observed by electron and fluorescence microscopy, respectively. Flow cytometry revealed the expression of GATA-4 and Sox9 by more than 99% of the cells, and abundant expression of a number of markers indicative of multipotent mesenchymal cells. Low detection of endogenous alkaline phosphatase activity after passaging showed that few peritubular myoid cells were present. GATA-4 and SOX9 expression were confirmed by reverse transcription polymerase chain reaction (RT-PCR), along with expression of stem cell factor (SCF), glial cell line-derived neurotrophic factor (GDNF), and bone morphogenic protein 4 (BMP4). Tight junctions were formed by Sertoli cells plated on transwell inserts coated with fibronectin as revealed by increased transepithelial electrical resistance (TER) and polarized secretion of the immunoregulatory protein, galectin-1. These primary Sertoli cell populations could be expanded dramatically in vitro and could be cryopreserved. The results show that functional human Sertoli cells can be propagated in vitro from testicular cells isolated from adult testis. The proliferative human Sertoli cells should have important applications in studying infertility

  18. Photon Regeneration Plans

    Ringwald, A


    Precision experiments exploiting low-energy photons may yield information on particle physics complementary to experiments at high-energy colliders, in particular on new very light and very weakly interacting particles, predicted in many extensions of the standard model. Such particles may be produced by laser photons send along a transverse magnetic field. The laser polarization experiment PVLAS may have seen the first indirect signal of such particles by observing an anomalously large rotation of the polarization plane of photons after the passage through a magnetic field. This can be interpreted as evidence for photon disappearance due to particle production. There are a number of experimental proposals to test independently the particle interpretation of PVLAS. Many of them are based on the search for photon reappearance or regeneration, i.e. for ``light shining through a wall''. At DESY, the Axion-Like Particle Search (ALPS) collaboration is currently setting up such an experiment.

  19. Photon regeneration plans

    Ringwald, A.


    Precision experiments exploiting low-energy photons may yield information on particle physics complementary to experiments at high-energy colliders, in particular on new very light and very weakly interacting particles, predicted in many extensions of the standard model. Such particles may be produced by laser photons send along a transverse magnetic field. The laser polarization experiment PVLAS may have seen the first indirect signal of such particles by observing an anomalously large rotation of the polarization plane of photons after the passage through a magnetic field. This can be interpreted as evidence for photon disappearance due to particle production. There are a number of experimental proposals to test independently the particle interpretation of PVLAS. Many of them are based on the search for photon reappearance or regeneration, i.e. for ''light shining through a wall''. At DESY, the Axion-Like Particle Search (ALPS) collaboration is currently setting up such an experiment. (orig.)

  20. A regenerable bitumen composition

    Sudzuki, K.; Asakava, Y.; Matsui, A.; Ogava, A.


    The regenerable bitumin composition includes the bitumen material (asphalt, oxidized bitumen, petroleum or asphalt pitch) emulsified by an cation emulsifier (alkylamine or an imidazole derivative) and additionally by a noniononic emulsifier (polyoxyethylenamine), an amide, which contains greater than 1 amide groups per molecule (amide derivative, imidazoline), an epoxide compound with greater than 1 epoxide group per molecule (preferably with an epoxy equivalent of 180 to 500), an inorganic compound which hardens in water (Portland cement or silicate cement) and additionally, water. The total content of the second third components is 1 to 200 parts per million to 100 parts of the first component, while the content of the fourth component is from 1 to 400 parts. The water content in the composition is 5 to 1,000 percent of the total content of the first three components. The patented composition is characterized by high stability, strength, chemical stability, resistance to water and good adhesion properties.

  1. The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting With Vision Impairment

    Peter M Allen


    Full Text Available The aim of this study was to investigate the level of vision impairment that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI shooting. Nineteen international-level shooters without vision impairment took part in the study. Participants shot an air rifle, while standing, towards a regulation target placed at the end of a 10m shooting range. Cambridge simulation glasses were used to simulate six different levels of vision impairment. Visual acuity (VA and contrast sensitivity (CS were assessed along with shooting performance in each of seven conditions of simulated impairment and compared to that with habitual vision. Shooting performance was evaluated by calculating each individual’s average score in every level of simulated vision impairment and normalising this score by expressing it as a percentage of the baseline performance achieved with habitual vision. Receiver Operating Characteristic (ROC curves were constructed to evaluate the ability of different VA and CS cut-off criteria to appropriately classify these athletes as achieving ‘expected’ or ‘below expected’ shooting results based on their performance with different levels of VA and CS. Shooting performance remained relatively unaffected by mild decreases in VA and CS, but quickly deteriorated with more moderate losses. The ability of visual function measurements to classify shooting performance was good, with 78% of performances appropriately classified using a cut-off of 0.53 logMAR and 74% appropriately classified using a cut-off of 0.83 logCS. The current inclusion criteria for VI shooting (1.0 logMAR is conservative, maximising the chance of including only those with an impairment that does impact performance, but potentially excluding some who do have a genuine impairment in the sport. A lower level of impairment would include more athletes who do have a genuine impairment but would potentially include those who do not

  2. Micropropagation of Vaccinium sp. by in vitro axillary shoot proliferation.

    Litwińczuk, Wojciech


    The Vaccinium genus contains several valuable fruit and ornamental species, among others: highbush blueberry (Vaccinium × corymbosum L.), cranberry (Vaccinium macrocarpon Ait.), and lingonberry (Vaccinium vitis-idaea L.). In some most popular and valuable cultivars, the conventional propagation methods, exploiting hard or soft wood cuttings, are inefficient. The demand for nursery plants could be fulfilled only by micropropagation. In principle cultivars are propagated in vitro through similar three-stage method, based on subculture of shoot explants on different culture media supplemented with IAA (0-4 mg/L) and 2iP (5-10 mg/L), and rooting shoots in vivo. The obtained plantlets are transferred to peat substrate and grown in the glasshouse until the end of growing period. The development of adventitious shoots should be monitored and controlled during in vitro stages. Many clones have specific requirements for growing conditions and/or are recalcitrant.

  3. A Study on Numerical Simulation of Core-Shooting Process


    In order to evaluate the main factors influencing the core-shooting process and to optimize the design of core boxes, the fluid-particle (air-sand) model has been built based on the two-phase flow theory. The fluid phase, air, and the particulate phase, sand granules, have been treated as a continuum. By using this model, it is possible to simulate the flow and compaction behavior of sand particles during the core-shooting process. To benchmark the calculated results, the shooting process has been recorded with a digital high speed camera, and the inlet condition of sand particles has also been achieved by using the camera. The preliminary results have showed that the calculation is in agreement with the testing results.

  4. The Mobile bypass Signal Arrests Shoot Growth by Disrupting Shoot Apical Meristem Maintenance, Cytokinin Signaling, and WUS Transcription Factor Expression.

    Lee, Dong-Keun; Parrott, David L; Adhikari, Emma; Fraser, Nisa; Sieburth, Leslie E


    The bypass1 (bps1) mutant of Arabidopsis (Arabidopsis thaliana) produces a root-sourced compound (the bps signal) that moves to the shoot and is sufficient to arrest growth of a wild-type shoot; however, the mechanism of growth arrest is not understood. Here, we show that the earliest shoot defect arises during germination and is a failure of bps1 mutants to maintain their shoot apical meristem (SAM). This finding suggested that the bps signal might affect expression or function of SAM regulatory genes, and we found WUSCHEL (WUS) expression to be repressed in bps1 mutants. Repression appears to arise from the mobile bps signal, as the bps1 root was sufficient to rapidly down-regulate WUS expression in wild-type shoots. Normally, WUS is regulated by a balance between positive regulation by cytokinin (CK) and negative regulation by CLAVATA (CLV). In bps1, repression of WUS was independent of CLV, and, instead, the bps signal down-regulates CK responses. Cytokinin treatment of bps1 mutants restored both WUS expression and activity, but only in the rib meristem. How the bps signal down-regulates CK remains unknown, though the bps signal was sufficient to repress expression of one CK receptor (AHK4) and one response regulator (AHP6). Together, these data suggest that the bps signal pathway has the potential for long-distance regulation through modification of CK signaling and altering gene expression. © 2016 American Society of Plant Biologists. All Rights Reserved.

  5. The optimization of regeneration tissue culture system of three chilli peppers cultivars based on the uniform design and the mathematical model equation.

    Hu, Tingzhang; Zeng, Hua; Chen, Zaigang; Huang, Xiaoyun; Yang, Yongwei; Wang, Guixue


    Using uniform random design optimization and the mathematical model equation we optimized the regeneration tissue culture system of the chilli pepper. An efficient and detailed plant reproducible protocol in vitro has been established using different explants and induction media for three chilli pepper cultivars. The result displayed that the seedlings at the curved hypocotyl stage were the best choice to prepare for explants, the genotype of explants affected shoot buds induction frequency and number of shoot buds per explant, and the cotyledon explant was more responsive than hypocotyl explant. The optimal media for maximum shoot initiation and regeneration and the optimal elongation medium were obtained. For Capsicum annuum var. annuum (cv. Xinsu), Capsicum annuum var. annuum (cv. Neimengchifeng) and Capsicum frutescens (cv. Xingfu), the induction rates were 99.17%, 97.50 and 96.11%, respectively; the elongation rates of shoot buds were 86.67%, 85.19% and 82.96%, respectively. The MS medium with 0.57 μM IAA and 0.69 μM NAA is the best choice for root induction. The frequency of their root emergence was 95.00-98.33%. Regenerated chilli peppers were successfully acclimatized and cultivated with 100% survival. This work will help to improve multiplication process and the genotype of chilli pepper, and may have commercial impact.

  6. NaCl and TDZ are Two Key Factors for the Improvement of In Vitro Regeneration Rate of Salicornia europaea L.

    Xiu-Ling Shi; He-Ping Han; Wu-Liang Shi; Yin-Xin Li


    The present study aimed to find out suitable conditions for the in vitro culture of Salicornla europaea L.and to develop an efficient regeneration system. S. europaea plants were regenerated successfully in vitro from callus derived from mature embryos. Via the method of 2,4-dichlorophenoxyacetic acid (2,4-D)short-treatment on mature seeds, callus was induced from hypocotyls on the MS medium with 4.55μmol/L N-phenyl-N'-1, 2, 3-thiadiazol-5-yl urea (TDZ) 3-4 weeks after the seeds germinated. The callus differentiated into shoots at a rate of 27.6% after subculture for one time on the same medium. When NaCl was included in the medium, shoots were formed in cluster and the shoot differentiation frequency was increased to 55.2%. The shoots were rooted when cultured on 1/2 MS medium supplemented with indole3-butyric acid (IBA), klnetin (KN) and activated charcoal (AC). The results indicated that NaCl and TDZ played an important role in the improvement of the regeneration rate of the halophyte, S. europaea.

  7. Cardiac Regeneration and Stem Cells.

    Zhang, Yiqiang; Mignone, John; MacLellan, W Robb


    After decades of believing the heart loses the ability to regenerate soon after birth, numerous studies are now reporting that the adult heart may indeed be capable of regeneration, although the magnitude of new cardiac myocyte formation varies greatly. While this debate has energized the field of cardiac regeneration and led to a dramatic increase in our understanding of cardiac growth and repair, it has left much confusion in the field as to the prospects of regenerating the heart. Studies applying modern techniques of genetic lineage tracing and carbon-14 dating have begun to establish limits on the amount of endogenous regeneration after cardiac injury, but the underlying cellular mechanisms of this regeneration remained unclear. These same studies have also revealed an astonishing capacity for cardiac repair early in life that is largely lost with adult differentiation and maturation. Regardless, this renewed focus on cardiac regeneration as a therapeutic goal holds great promise as a novel strategy to address the leading cause of death in the developed world.

  8. Biomaterial selection for tooth regeneration.

    Yuan, Zhenglin; Nie, Hemin; Wang, Shuang; Lee, Chang Hun; Li, Ang; Fu, Susan Y; Zhou, Hong; Chen, Lili; Mao, Jeremy J


    Biomaterials are native or synthetic polymers that act as carriers for drug delivery or scaffolds for tissue regeneration. When implanted in vivo, biomaterials should be nontoxic and exert intended functions. For tooth regeneration, biomaterials have primarily served as a scaffold for (1) transplanted stem cells and/or (2) recruitment of endogenous stem cells. This article critically synthesizes our knowledge of biomaterial use in tooth regeneration, including the selection of native and/or synthetic polymers, three-dimensional scaffold fabrication, stem cell transplantation, and stem cell homing. A tooth is a complex biological organ. Tooth loss represents the most common organ failure. Tooth regeneration encompasses not only regrowth of an entire tooth as an organ, but also biological restoration of individual components of the tooth including enamel, dentin, cementum, or dental pulp. Regeneration of tooth root represents perhaps more near-term opportunities than the regeneration of the whole tooth. In the adult, a tooth owes its biological vitality, arguably more, to the root than the crown. Biomaterials are indispensible for the regeneration of tooth root, tooth crown, dental pulp, or an entire tooth.

  9. [Induction and in vitro culture of hairy roots of Dianthus caryophyllus and its plant regeneration].

    Shi, Heping; Zhu, Yuanfeng; Wang, Bei; Sun, Jiangbing; Huang, Shengqin


    To use Agrobacterium rhizogenes-induced hairy roots to create new germplasm of Dianthus caryophyllus, we transformed D. caryophyllus with A. rhizogenes by leaf disc for plant regeneration from hairy roots. The white hairy roots could be induced from the basal surface of leaf explants of D. caryophyllus 12 days after inoculation with A. rhizogenes ATCC15834. The percentage of the rooting leaf explants was about 90% 21 days after inoculation. The hairy roots could grow rapidly and autonomously in liquid or solid phytohormone-free MS medium. The transformation was confirmed by PCR amplification of rol gene of Ri plasmid and silica gel thin-layer chromatography of opines from D. caryophyllus hairy roots. Hairy roots could form light green callus after cultured on MS+6-BA 1.0-3.0 mg/L + NAA 0.1-0.2 mg/L for 15 days. The optimum medium for adventitious shoots formation was MS + 6-BA 2.0 mg/L + NAA 0.02 mg/L, where the rate of adventitious shoot induction was 100% after cultured for 6 weeks. The mean number of adventitious shoot per callus was 30-40. The adventitious shoots can form roots when cultured on phytohormone-free 1/2 MS or 1/2 MS +0.5 mg/L NAA for 10 days. When the rooted plantlets transplanted in the substrate mixed with perlite sand and peat (volume ratio of 1:2), the survival rate was above 95%.

  10. CLAVATA-WUSCHEL signaling in the shoot meristem.

    Somssich, Marc; Je, Byoung Il; Simon, Rüdiger; Jackson, David


    Shoot meristems are maintained by pluripotent stem cells that are controlled by CLAVATA-WUSCHEL feedback signaling. This pathway, which coordinates stem cell proliferation with differentiation, was first identified in Arabidopsis, but appears to be conserved in diverse higher plant species. In this Review, we highlight the commonalities and differences between CLAVATA-WUSCHEL pathways in different species, with an emphasis on Arabidopsis, maize, rice and tomato. We focus on stem cell control in shoot meristems, but also briefly discuss the role of these signaling components in root meristems. © 2016. Published by The Company of Biologists Ltd.

  11. Algorithm on robot soccer pass and shoot a ball


    Introduces of robot soccer's competition software of Harbin Institute of Technology(HIT), the con cept of running range and the method of calculating the running range for both the opponent and our teammates according to the distances Between the ball and robot soccers, and therefore the method of calculating the angle that the robot passes or shoots the ball according to the running ranges of both sides. And gives the examples of passing the ball when the ball's position is in the backcourt and shooting the ball when the ball's position is in the frontcourt.

  12. Preliminary results from simulations of temperature oscillations in Stirling engine regenerator matrices

    Andersen, Stig Kildegaard [Department of Mechanical Engineering, Technical University of Denmark, DK-2800 Lyngby (Denmark)]. E-mail:; Carlsen, Henrik [Department of Mechanical Engineering, Technical University of Denmark, DK-2800 Lyngby (Denmark); Thomsen, Per Grove [Informatics and Mathematical Modelling, Technical University of Denmark, DK-2800 Lyngby (Denmark)


    The objective of this study has been to create a Stirling engine model for studying the effects of regenerator matrix temperature oscillations on Stirling engine performance. A one-dimensional model with axial discretisation of engine components has been formulated using the control volume method. The model contains a system of ordinary differential equations (ODEs) derived from mass and energy balances for gas filled control volumes and energy balances for regenerator matrix control masses. Interpolation methods with filtering properties are used for state variables at control volume interfaces to reduce numerical diffusion and/or non-physical oscillations. Loss mechanisms are included directly in the governing equations as terms in the mass and energy balances. Steady state periodic solutions that satisfy cyclic boundary conditions and integral conditions are calculated using a custom built shooting method. It has been found possible to accurately solve the stiff ODE system that describes the coupled thermodynamics of the gas and the regenerator matrix and to reliably find periodic steady state solutions to the model. Preliminary results indicate that the regenerator matrix temperature oscillations do have significant impact on the regenerator loss, the cycle power output, and the cycle efficiency and thus deserve further study.

  13. Effect of plant growth regulators and explant types on regeneration and micropropagation of a commercial strawberry cultivar (Fragaria ×ananassa cv. Selva

    G. Madani


    Full Text Available Strawberry (Fragaria× ananassa L. is an important horticultural product that is highly acceptable because of its desirable taste, flavor, mineral elements, vitamins and secondary metabolites. Conventionally, strawberries are vegetatively propagated by runners arising from axillary buds on the plant crown. Plant propagation through runner produces a limited number of propagules. In the view of mass propagation and transformation, it is highly desirable to optimize methods of rapid, efficient and large scale multiplication of Fragaria X ananassa Duch. through tissue culture. In present study, developing an effective protocol for regeneration of strawberry cv. Selva, different explants (leaf disk, shoot tips and hypocotyls and media modifications were examined. The best response towards shoot induction was observed on shoot tip explants cultured on MS medium supplemented with 2 mg/l of BAP and IAA. Direct shoots emerged from hypocotyls grown on MS medium supplemented by 2,4-D, BAP and TDZ at 0.01, 0.1 and 1 mg/l respectively. Indirect shoot regeneration was produced from hypocotyls on MS medium containing 2 mg/l of BAP. Using activated charcoal enhanced explants proliferation on culture media due to decreasing the toxic metabolites, phenolic exudation and adsorption of inhibitory compounds.

  14. Impairment of liver regeneration by the histone deacetylase inhibitor valproic acid in mice

    Qi KE; Rui-na YANG; Feng YE; Yu-jia WANG; Qiong WU; Li LI; Hong BU


    Background and objective:Liver regeneration is a complex process regulated by a group of genetic and epigenetic factors.A variety of genetic factors have been reported,whereas few investigations have focused on epigenetic regulation during liver regeneration.In the present study,valproic acid (VPA),a histone deacetylase (HDAC)inhibitor,was used to investigate the effect of HDAC on liver regeneration.Methods:VPA was administered via intraperitoneal injection to 2/3 partially hepatectomized mice to detect hepatocyte proliferation during liver regeneration.The mice were sacrificed,and their liver tissues were harvested at sequential time points from 0 to 168 h after treatment.DNA synthesis was detected via a BrdU assay,and cell proliferation was tested using Ki-67.The expressions of cyclin D1,cyclin E,cyclin dependent kinase 2 (CDK2),and CDK4 were detected by Western blot analysis.Chromatin immunoprecipitation (ChIP) assay was used to examine the recruitment of HDACs to the target promoter regions and the expression of the target gene was detected by Western blot.Results:Immunohistochemical analysis showed that cells positive for BrdU and Ki-67 decreased,and the peak of BrdU was delayed in the VPA-administered mice.Consistently,cyclin D1 expression was also delayed.We identified B-myc as a target gene of HDACs by complementary DNA (cDNA) microarray.The expression of B-myc increased in the VPA-administered mice after hepatectomy (PH).The ChIP assay confirmed the presence of HDACs at the B-myc promoter.Conclusions:HDAC activities are essential for liver regeneration,inhibiting HDAC activities delays liver regeneration and induces liver cell cycle arrest,thereby causing an anti-proliferative effect on liver regeneration.

  15. In vitro Embryogenesis Derived from Shoot Tips in Mass Propagation of Two Selected-Clones of Phalaenopsis

    Budi WINARTO


    Full Text Available Phalaenopsis is of high economic value and market demand in Indonesia; however, orchid products are mostly imported from other countries. ‘Kristina Dwi’ (KD 69.274 and ‘Dedeh’ (D 802.28 are two selected clones with high potential utilized and developed commercially. To support their commercialization, a reliable in vitro propagation protocol is essential. In the current study, an in vitro mass propagation protocol for KD 69.274 and D 802.28 clones was successfully established using shoot tips as explant sources. A high number of embryos, up to 8.2 embryos per explant, with 58.5% explant regeneration, and 3.5 regenerated-explants in average were regenerated from shoot tips of KD 69.274 clone cultured on half-strength Murashige and Skoog (MS medium, with full strength micro, Fe-chellate and vitamin containing 0.5 mg/L thidiazuruon (TDZ and 0.25 mg/L N6-benzyladenine (BA. The initial embryos were proliferated by culturing embryos individually on half-strength MS medium with 0.13 mg/L TDZ and 0.25 mg/L BA and resulted in high embryo regeneration up to 91.4%, with 10.2 embryos per explant and no embryo browning. The embryos were multiplied under periodical subcultures of 3 months each, resulting in gradual increasing number of embryos from the first subculture till the fifth subculture, with 23.6 embryos produced, then declined afterward. The embryos were easily germinated on half-strength MS medium with full strength of vitamin and hormone free, with 73.9% embryo germination and 14.9 germinated embryos. Healthy plantlets were stimulated on the same medium with 2 g/L activated charcoal (AC and successfully acclimatized on Cycas rumphii bulk, with 88.3% survival plantlets. Finally, it can be summarized that a new in vitro mass propagation protocol, as new alternative choice for Phalaenopsis propagation, was successfully established. Full Text: PDF DOI:

  16. Zebrafish fin regeneration after cryoinjury-induced tissue damage

    Bérénice Chassot


    Full Text Available Although fin regeneration following an amputation procedure has been well characterized, little is known about the impact of prolonged tissue damage on the execution of the regenerative programme in the zebrafish appendages. To induce histolytic processes in the caudal fin, we developed a new cryolesion model that combines the detrimental effects of freezing/thawing and ischemia. In contrast to the common transection model, the damaged part of the fin was spontaneously shed within two days after cryoinjury. The remaining stump contained a distorted margin with a mixture of dead material and healthy cells that concomitantly induced two opposing processes of tissue debris degradation and cellular proliferation, respectively. Between two and seven days after cryoinjury, this reparative/proliferative phase was morphologically featured by displaced fragments of broken bones. A blastemal marker msxB was induced in the intact mesenchyme below the damaged stump margin. Live imaging of epithelial and osteoblastic transgenic reporter lines revealed that the tissue-specific regenerative programmes were initiated after the clearance of damaged material. Despite histolytic perturbation during the first week after cryoinjury, the fin regeneration resumed and was completed without further alteration in comparison to the simple amputation model. This model reveals the powerful ability of the zebrafish to restore the original appendage architecture after the extended histolysis of the stump.

  17. Stathmin regulates keratinocyte proliferation and migration during cutaneous regeneration.

    Schmitt, Sabrina; Safferling, Kai; Westphal, Kathi; Hrabowski, Manuel; Müller, Ute; Angel, Peter; Wiechert, Lars; Ehemann, Volker; Müller, Benedikt; Holland-Cunz, Stefan; Stichel, Damian; Harder, Nathalie; Rohr, Karl; Germann, Günter; Matthäus, Franziska; Schirmacher, Peter; Grabe, Niels; Breuhahn, Kai


    Cutaneous regeneration utilizes paracrine feedback mechanisms to fine-tune the regulation of epidermal keratinocyte proliferation and migration. However, it is unknown how fibroblast-derived hepatocyte growth factor (HGF) affects these mutually exclusive processes in distinct cell populations. We here show that HGF stimulates the expression and phosphorylation of the microtubule-destabilizing factor stathmin in primary human keratinocytes. Quantitative single cell- and cell population-based analyses revealed that basal stathmin levels are important for the migratory ability of keratinocytes in vitro; however, its expression is moderately induced in the migration tongue of mouse skin or organotypic multi-layered keratinocyte 3D cultures after full-thickness wounding. In contrast, clearly elevated stathmin expression is detectable in hyperproliferative epidermal areas. In vitro, stathmin silencing significantly reduced keratinocyte proliferation. Automated quantitative and time-resolved analyses in organotypic cocultures demonstrated a high correlation between Stathmin/phospho-Stathmin and Ki67 positivity in epidermal regions with proliferative activity. Thus, activation of stathmin may stimulate keratinocyte proliferation, while basal stathmin levels are sufficient for keratinocyte migration during cutaneous regeneration.

  18. Stathmin regulates keratinocyte proliferation and migration during cutaneous regeneration.

    Sabrina Schmitt

    Full Text Available Cutaneous regeneration utilizes paracrine feedback mechanisms to fine-tune the regulation of epidermal keratinocyte proliferation and migration. However, it is unknown how fibroblast-derived hepatocyte growth factor (HGF affects these mutually exclusive processes in distinct cell populations. We here show that HGF stimulates the expression and phosphorylation of the microtubule-destabilizing factor stathmin in primary human keratinocytes. Quantitative single cell- and cell population-based analyses revealed that basal stathmin levels are important for the migratory ability of keratinocytes in vitro; however, its expression is moderately induced in the migration tongue of mouse skin or organotypic multi-layered keratinocyte 3D cultures after full-thickness wounding. In contrast, clearly elevated stathmin expression is detectable in hyperproliferative epidermal areas. In vitro, stathmin silencing significantly reduced keratinocyte proliferation. Automated quantitative and time-resolved analyses in organotypic cocultures demonstrated a high correlation between Stathmin/phospho-Stathmin and Ki67 positivity in epidermal regions with proliferative activity. Thus, activation of stathmin may stimulate keratinocyte proliferation, while basal stathmin levels are sufficient for keratinocyte migration during cutaneous regeneration.

  19. Role of tissue engineering in dental pulp regeneration

    Shruti Sial


    Full Text Available Stem cells constitute the source of differentiated cells for the generation of tissues during development, and for regeneration of tissues that are diseased or injured postnatally. In recent years, stem cell research has grown exponentially owing to the recognition that stem cell-based therapies have the potential to improve the life of patients with conditions that span from Alzheimer′s disease to cardiac ischemia to bone or tooth loss. Growing evidence demonstrates that stem cells are primarily found in niches and that certain tissues contain more stem cells than others. Among these tissues, the dental pulp is considered a rich source of mesenchymal stem cells that are suitable for tissue engineering applications. It is known that dental pulp stem cells have the potential to differentiate into several cell types, including odontoblasts, neural progenitors, osteoblasts, chondrocytes, and adipocytes. The dental pulp stem cells are highly proliferative. Collectively, the multipotency, high proliferation rates, and accessibility make the dental pulp an attractive source of mesenchymal stem cells for tissue regeneration. This review discusses fundamental concepts of stem cell biology and tissue engineering within the context of regenerative dentistry.


    Frendy Nurochwan Febryanto


    Full Text Available The purpose of this study was to determine the learning lay up shoot using basic audiovisual media shoot lay ups can improve learning outcomes shoot lay ups in class VIIIA Starch Canisius junior year 2013/2014 . This study uses Classroom Action Research ( CAR. The technique of collecting data through observation and assessment of learning outcomes shoot basketball lay up. Data analysis techniques used in this research is descriptive . At the end of the first cycle activity of teachers in teaching basic techniques lay up shoot using audio-visual media reaches 76.19%, whereas at the end of the first cycle of student activity during the learning process lay up shoot using audio-visualmediareaches78.57%. At the end of the second cycle of activity of teachers in teaching basic techniques lay up shoot using audio-visual media reaches 85.71%, whereas at the end of the second cycle of activity of students during the learning process lay up shoot using audio-visual media reaches 92.86%. Based on the results of the study it can be concluded that learning the lay-up shoot using basic audiovisual media shoot lay ups can improve student learning outcomes at Canisius junior class VIIIA Pati year 2013/2014.

  1. Quiescent and proliferative fibroblasts exhibit differential p300 HAT activation through control of 5-methoxytryptophan production.

    Huei-Hsuan Cheng

    Full Text Available Quiescent fibroblasts possess unique genetic program and exhibit high metabolic activity distinct from proliferative fibroblasts. In response to inflammatory stimulation, quiescent fibroblasts are more active in expressing cyclooxygenase-2 and other proinflammatory genes than proliferative fibroblasts. The underlying transcriptional mechanism is unclear. Here we show that phorbol 12-myristate 13-acetate (PMA and cytokines increased p300 histone acetyltransferase activity to a higher magnitude (> 2 fold in quiescent fibroblasts than in proliferative fibroblasts. Binding of p300 to cyclooxygenase-2 promoter was reduced in proliferative fibroblasts. By ultrahigh-performance liquid chromatography coupled with a quadrupole time of flight mass spectrometer and enzyme-immunoassay, we found that production of 5-methoxytryptophan was 2-3 folds higher in proliferative fibroblasts than that in quiescent fibroblasts. Addition of 5-methoxytryptophan and its metabolic precursor, 5-hydroxytryptophan, to quiescent fibroblasts suppressed PMA-induced p300 histone acetyltransferase activity and cyclooxygenase-2 expression to the level of proliferative fibroblasts. Silencing of tryptophan hydroxylase-1 or hydroxyindole O-methyltransferase in proliferative fibroblasts with siRNA resulted in elevation of PMA-induced p300 histone acetyltransferase activity to the level of that in quiescent fibroblasts, which was rescued by addition of 5-hydroxytryptophan or 5-methoxytryptophan. Our findings indicate that robust inflammatory gene expression in quiescent fibroblasts vs. proliferative fibroblasts is attributed to uncontrolled p300 histone acetyltransferase activation due to deficiency of 5-methoxytryptophan production. 5-methoxytryptophan thus is a potential valuable lead compound for new anti-inflammatory drug development.

  2. Some features of one-year-old tart Cherry shoots of cv. Sehattenmorelle

    Dariusz Świetlik


    Full Text Available The purpose of this study was to obtain data on the relationship between the length of 1-year-old shoots and their fruiting, and both their terminal and lateral growtn produced in the current year. The measurements were taken in 1977 and 1979 from the tart cherry trees of cv. Schattenmorelle grafted of Prunus mahaleb L. or Prunus avium L. grown in loose sandy soil. In 1977 there were more shoots of over 30 cm than in 1979. The longer the shoots, the more lateral shoots were there. Only the shortest shoots (1-10 cm bore more fruit per unit length as compared to the longer shoots.

  3. [Distribution patterns of shoots, flowers and seeds in Ginkgo biloba canopy and their relationships].

    Wang, J; Wei, G


    The distribution patterns of shoots, flowers and seeds in the canopy of 14 years old engrafted Ginkgo biloba and their relationships were investigated with stratification method. The result shows that long shoots, short shoots, bearing-shoots and flowers uniformly distributed in the central section of canopy. From the top to the bottom, the average age and the divaricating angle of long shoots increase 51.3% of the seeds distributed in 180-320 cm layer from the ground. The number of shoots, flowers and seeds in different canopy layers was closely correlated.

  4. C/sub 4/ photosynthesis in Euphorbia degeneri and E. remyi: a comparison of photosynthetic carbon metabolism in leaves, callus cultures and regenerated plants

    Ruzin, S.E.


    Based on analysis of /sup 14/CO/sub 2/ fixation kinetics and assays of enzymes related to C/sub 4/ metabolism (NAD-ME, NADP-ME, NAD-MDH, NADP-MDH, AST, ALT), leaves and regenerated plants of Euphorbia degeneri exhibit a modified NADP-ME-type photosynthesis. Apparently, both aspartate and malate are used for transport of CO/sub 2/ to bundle sheath cells. Callus grown on either non-shoot-forming or shoot-forming media fixes CO/sub 2/ into RPP-cycle intermediates and sucrose, as well as malate and aspartate. /sup 14/CO/sub 2/ pulse/chase kinetics show no significant loss of label from C/sub 4/ acids throughout a one minute chase. Analysis of PEPCase revealed the presence of 2 isoenzymes in both leaf and regenerated plant tissues (K/sub m/ (PEP) = 0.080 and 0.550) but only one isoenzyme in callus (K/sub m/ = 0.100). It appears that C/sub 4/ photosynthesis does not occur in callus derived from this C/sub 4/ dicot but is regenerated concomitant with shoot regeneration, and ..beta..-carboxylation of PEP in callus, mediated by the low K/sub m/ isoenzyme of PEPCase, produces C/sub 4/ acids that are not involved in the CO/sub 2/ shuttle mechanism characteristic of C/sub 4/ photosynthesis. 161 references, 19 figures, 12 tables.

  5. Chitosan Degradation Products Promote Nerve Regeneration by Stimulating Schwann Cell Proliferation via miR-27a/FOXO1 Axis.

    Wang, Yongjun; Zhao, Yahong; Sun, Cheng; Hu, Wen; Zhao, Jing; Li, Guicai; Zhang, Luzhong; Liu, Mei; Liu, Yan; Ding, Fei; Yang, Yumin; Gu, Xiaosong


    Natural polysaccharides are biomaterials widely used for constructing scaffolds in tissue engineering. While natural polysaccharides have been shown to robustly promote tissue regeneration, the underlying molecular mechanism remains largely unknown. Here, we show that chitooligosaccharides (COS), the intermediate products of chitosan degradation, stimulate peripheral nerve regeneration in rats. Our experiment also shows that COS stimulate the proliferation of Schwann cells (SCs) during nerve regeneration. By analyzing the transcriptome and gene regulatory network, we identified the miR-27a/FOXO1 axis as the main signaling pathway for mediating the proliferative effects of COS on SCs. COS increase the expression level of miR-27a and cause a reduction of FOXO1, which subsequently accelerates the cell cycle and stimulates SC proliferation to stimulate nerve regeneration. These findings define a basic pathway for oligosaccharides-mediated cell proliferation and reveal a novel aspect of polysaccharide biomaterials in tissue engineering.

  6. Four Hypotheses to Explain Axillary Budbreak after Removal of Flower Shoots in a Cut-rose Crop

    Wubs-Timmermans, A.M.; Heuvelink, E.; Marcelis, L.F.M.; Okello, R.C.; Buck-Sorlin, G.H.; Vos, J.


    When flower-bearing shoots in cut-rose (Rosa ×hybrida) are harvested (removed), a varying number of repressed axillary buds on the shoot remainder start to grow into new shoots (budbreak). Besides removing within-shoot correlative inhibition, it is hypothesized that shoot removal leads to 1) increas

  7. An experimental study of passive regenerator geometries

    Engelbrecht, Kurt; Nielsen, Kaspar Kirstein; Pryds, Nini


    this article studies the effects of regenerator geometry on performance for flat plate regenerators. This paper investigates methods of improving the performance of flat plate regenerators for use in AMR systems and studies how manufacturing variation affects regenerator performance. In order to eliminate...... experimental uncertainty associated with magnetocaloric material properties, all regenerators are made of aluminum. The performance of corrugated plates and dimpled plates are compared to traditional flat plate regenerators for a range of cycle times and utilizations. Each regenerator is built using 18...

  8. [Adult resident cardiomyocytes wake up: new axis for cardiac tissue regeneration].

    Mias, Céline; Genet, Gaël; Pathak, Atul; Sénard, Jean-Michel; Galés, Céline


    All cardiomyopathies and more specifically myocardial infarction always evolve to cardiomyocytes death and the ensuing heart failure setting. So far, cardiac regenerative medicine has focused on the use of stem cells and completely ignored the resident cardiomyocytes, assumed in a postmitotic state. However, recent findings in zebrafish and mammalians challenge this view and suggest that these cells have some capacity to proliferate and can contribute to heart regeneration. In this review, we propose an overall synthesis about knowledge of the proliferative and regenerative capacities of resident cardiomyocytes, dealing with some mechanistic aspects. In the future, the accurate identification of molecular mechanisms allowing wake-up of resident cardiomyocyte proliferation will certainly open new therapeutic avenues in cardiac regeneration. © 2012 médecine/sciences – Inserm / SRMS.

  9. Regenerable Contaminant Removal System Project

    National Aeronautics and Space Administration — The Regenerable Contaminant Removal System (RCRS) is an innovative method to remove sulfur and halide compounds from contaminated gas streams to part-per-billion...

  10. A numerical method of regenerator

    Zhu, Shaowei [Aisin Seiki Co. Ltd., Aichi (Japan); Matsubara, Yoichi [Nihon Univ., Chiba (Japan). Inst. of Quantum Science


    A numerical method for regenerators is introduced in this paper. It is not only suitable for the regenerators in cryocoolers and Stirling engines, but also suitable for the stacks in acoustic engines and the pulse tubes in pulse tube refrigerators. The numerical model is one dimensional periodic unsteady flow model. The numerical method is based on the control volume concept with the implicitly solve method. The iteration acceleration method, which considers the one-dimensional periodic unsteady problem as the steady two-dimensional problem, is used for decreasing the calculation time. By this method, the regenerator in an inertance tube pulse tube refrigerator was simulated. The result is useful for understanding how the inefficiency of the regenerator changes with the inertance effect. (author)

  11. A numerical method of regenerator

    Zhu, Shaowei; Matsubara, Yoichi


    A numerical method for regenerators is introduced in this paper. It is not only suitable for the regenerators in cryocoolers and Stirling engines, but also suitable for the stacks in acoustic engines and the pulse tubes in pulse tube refrigerators. The numerical model is one dimensional periodic unsteady flow model. The numerical method is based on the control volume concept with the implicitly solve method. The iteration acceleration method, which considers the one-dimensional periodic unsteady problem as the steady two-dimensional problem, is used for decreasing the calculation time. By this method, the regenerator in an inertance tube pulse tube refrigerator was simulated. The result is useful for understanding how the inefficiency of the regenerator changes with the inertance effect.

  12. Instructive composites for bone regeneration

    Barbieri, D.


    Developing new biomaterials for tissue regeneration requires careful balance between many factors, which is challenging because, on one side, such materials must provide complex information, through their physicochemical properties to actively interact with the biological surroundings and induce tis

  13. Early summer drought stress during the first growing year stimulates extra shoot growth in oak seedlings (Quercus petraea

    Arion eTurcsán


    Full Text Available More severe summer droughts are predicted for mid-latitudes in Europe. To evaluate the impact on forest ecosystems and more specifically on forest regeneration, we studied the response to summer drought in oak seedlings (Quercus petraea. Acorns were collected from different mother trees in three stands in Belgium, sown in pots and grown in non-heated greenhouse conditions. We imposed severe drought on the seedlings in early summer by first watering the pots to saturation and then stopping any watering. Weight of the pots and stomatal conductance were regularly measured. Re-watering followed this drought period of five weeks. Height of the seedlings and apical bud development were observed. Stomatal resistance increased towards the end of the experiment in the drought-treated group and was restored after re-watering. The seedlings from the drought treatment displayed a higher probability to produce additional shoot growth after re-watering (p ≤ 0.05. A higher competition for resources (two plants per pot increased this chance. Although this chance was also higher for smaller seedlings, the actual length of the extra growth after re-watering was higher for larger seedlings (p ≤ 0.01. Both in the drought-treated and in the control group the autochthonous provenance growing on a xeric site produced less extra shoots compared to the two other provenances. Finally, stressed plants showed less developed apical buds compared to the control group after re-watering, suggesting a phenological effect on the growth cycle of oaks (p ≤ 0.0001. The higher chance for an extra shoot growth after the drought period can be considered as a compensation for the induced growth arrest during the drought period.

  14. TCPs, WUSs, and WINDs: Families of transcription factors that regulate shoot meristem formation, stem cell maintenance, and somatic cell differentiation

    Miho eIkeda


    Full Text Available In contrast to somatic mammalian cells, which cannot alter their fate, plant cells can dedifferentiate to form totipotent callus cells and regenerate a whole plant, following treatment with specific phytohormones. However, the regulatory mechanisms and key factors that control differentiation-dedifferentiation and cell totipotency have not been completely clarified in plants. Recently, several plant transcription factors that regulate meristem formation and dedifferentiation have been identified and include members of the TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP, WUSCHEL (WUS, and WOUND INDUCED DEDIFFERENTIATION (WIND1 families. WUS and WIND positively control plant cell totipotency, while TCP negatively controls it. Interestingly, TCP is a transcriptional activator that acts as a negative regulator of shoot meristem formation, and WUS is a transcriptional repressor that positively maintains totipotency of the stem cells of the shoot meristem. We describe here the functions of TCP, WUS and WIND transcription factors in the regulation of differentiation-dedifferentiation by positive and negative transcriptional regulators.

  15. Role of acetylcholine on plant root-shoot signal transduction


    The role of acetylcholine (ACh) on plant root- shoot communication was investigated using the root-split system of Vicia faba L. In the experiments, slight osmotic stress caused the decrease of ACh content in root tips and the xylem sap transported up per time unit from root tip to the shoot when the water potential of the shoot was kept unchanged. It also caused the decrease of ACh content in the abaxial epidermis. The decrease was highly correlative to the changes of transpiration rate, suggesting that the decrease of ACh content probably functions as a signal to regulate stomatal behavior. The effect of osmotic stress might be mainly through the inhibition of the ACh synthesis in root tip; thus further influences the ACh content in root tip, xylem sap and abaxial epidermis and resulting in the changes of stomatal behavior. These results provide new evidence that plants transduce positive and negative signals among roots and shoots to coordinate stomatal behavior and adapt to variable environments.

  16. Node position influences viability and contamination in hazelnut shoot

    Initiation of shoot cultures is difficult in many woody plants due to internal microbial contaminants and general lack of juvenility in material from the source plants. Hazelnuts (Corylus avellana L.) are generally difficult to initiate into culture for these same reasons. This study was designed to...

  17. Specification of Epidermal Cell Fate in Plant Shoots

    Shinobu eTakada


    Full Text Available Land plants have evolved a single layer of epidermal cells, which are characterized by mostly anticlinal cell division patterns, formation of a waterproof coat called cuticle, and unique cell types such as stomatal guard cells and trichomes. The shoot epidermis plays important roles not only to protect plants from dehydration and pathogens but also to ensure their proper organogenesis and growth control. Extensive molecular genetic studies in Arabidopsis and maize have identified a number of genes that are required for epidermal cell differentiation. However, the mechanism that specifies shoot epidermal cell fate during plant organogenesis remains largely unknown. Particularly, little is known regarding positional information that should restrict epidermal cell fate to the outermost cell layer of the developing organs. Recent studies suggested that certain members of the HD-ZIP class IV homeobox genes are possible master regulators of shoot epidermal cell fate. Here, we summarize the roles of the regulatory genes that are involved in epidermal cell fate specification and discuss the possible mechanisms that limit the expression and/or activity of the master transcriptional regulators to the outermost cell layer in plant shoots.

  18. Phytotoxic furanocoumarins from the shoots of Semenovia transiliensis Regel & Herder

    Discovery of novel, natural herbicides has become important to manage increasing weed resistance to synthetic herbicides and environmental issues. The systematic bioassay-guided fractionation and purification of the methylene chloride/methanol extract of the shoots of Semenovia transiliensis led to ...

  19. Connecting the Dots: Lessons from the Virginia Tech Shootings

    Davies, Gordon K.


    The shootings that took place last spring on the campus of Virginia Polytechnic Institute and State University, located in Blacksburg, Virginia, elicited a host of reactions, many deeply emotional. In groups of college and university presidents, the response was generally empathetic. Indeed, they were right to be put on alert by the random and…

  20. Rootstocks: diversity, domestication and impacts on shoot phenotypes

    Grafting is an ancient agricultural practice that joins the root system (rootstock) of one plant to the shoot system (scion) of another individual. It is most commonly employed in woody perennial crops such as Apples, Grapes, and Citrus species to shorten scion juvenile stage length, facilitate clo...