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1

Preventive and Curative Biological Treatments for Control of Botrytis cinerea Stem Canker of Greenhouse Tomatoes  

Microsoft Academic Search

The effects of biological treatments with PlantShield®, Prestop®, Quadra 136, RootShield®, and S33 (Rhodosporidium diobovatum) and chemical treatment with Decree® applied as a preventive or curative sprays on stem canker caused by Botrytis cinerea on tomato plants grown in sawdust were studied under near-commercial greenhouse conditions. Prestop® and Decree®, applied as preventive or curative sprays, PlantShield® applied as curative spray,

R. S. Utkhede; S. Mathur

2006-01-01

2

TPCP: Pitch canker PITCH CANKER  

E-print Network

to commercial forestry in South Africa today. In the past seven years, Fusarium subglutinans f.sp. pini or FSP was first recorded in South Africa in 1991, where it was found causing a root disease of Pinus patula severe and extensive root disease of pine seedlings in nurseries. Dead top associated with stem canker

3

Effects of biological and chemical treatments on Botrytis stem canker and fruit yield of tomato under greenhouse conditions  

Microsoft Academic Search

Experiments were conducted to identify, by in vitro dual culture tests, potential biological control agents producing antibiotics and to evaluate selected biological and chemical agents for control of stem canker caused by Botrytis cinerea on tomato plants (Lycopersicon esculentum) grown in yellow cedar sawdust in a research greenhouse. Four strains of Bacillus subtilis and one each of Enterobacter agglomerans and

R. Utkhede; C. Bogdanoff; J. McNevin

2001-01-01

4

Geographic variation in severity of phoma stem canker and Leptosphaeria maculans\\/ L. biglobosa populations on UK winter oilseed rape ( Brassica napus )  

Microsoft Academic Search

Phoma stem canker, caused by Leptosphaeria maculans and L. biglobosa, is the most important disease of oilseed rape in Europe. Differences between L. maculans and L. biglobosa in their life-cycles enable the two species to co-exist on oilseed rape crops over a cropping season. This review considers\\u000a the factors affecting geographic variation in the severity of phoma stem canker epidemics

Jenna F. Stonard; Akinwunmi O. Latunde-Dada; Yong-Ju Huang; Jonathan S. West; Neal Evans; Bruce D. L. Fitt

2010-01-01

5

Inheritance of resistance to southern stem canker (Diaporthe phaseolorum f.s. meridionalis) in soybean [Glycine max (L.) Merr.  

E-print Network

encoun- tered among children. Thesis format follows Crop Science style. Recently, soybean production in the southeastern United States was threatened by stem canker, a dangerous disease caused by the fungus Diaporrhe pItaseolorum (Cke & Elh) f. s.... meridionalis (Athow & Caldwell) (2, 3). This fungus is capable of infecting and killing plants prior to completion of the seed-filling stage. Plants are usually infected during the early vegetative stages, but disease symptoms do not ap- pear until later...

Ngeleka, Kadima

2012-06-07

6

Canker Sores  

MedlinePLUS

... the base of your gums or under your tongue. Canker sores are different from fever blisters, which usually are on the outside of your lips or the corners of your mouth. Canker sores are also called aphthous ulcers. Anyone can get canker sores, but women and ...

7

Involvement of microRNA-Mediated Gene Expression Regulation in the Pathological Development of Stem Canker Disease in Populus trichocarpa  

PubMed Central

MicroRNAs (miRNAs), a type of short (21–23 nucleotides), non-coding RNA molecule, mediate repressive gene regulation through RNA silencing at the post-transcriptional level, and play an important role in defense and response to abiotic and biotic stresses. In the present study, Affymetrix® miRNA Array, real-time quantitative PCR (qPCR) for miRNAs and their targets, and miRNA promoter analysis were used to validate the gene expression patterns of miRNAs in Populus trichocarpa plantlets induced with the poplar stem canker pathogen, Botryosphaeria dothidea. Twelve miRNAs (miR156, miR159, miR160, miR164, miR166, miR168, miR172, miR319, miR398, miR408, miR1448, and miR1450) were upregulated in the stem bark of P. trichocarpa, but no downregulated miRNAs were found. Based on analysis of the miRNAs and their targets, a potential co-regulatory network was developed to describe post-transcriptional regulation in the pathological development of poplar stem canker. There was highly complex cross-talk between diverse miRNA pathway responses to biotic and abiotic stresses. The results suggest that miR156 is probably an integral component of the miRNA response to all environmental stresses in plants. Cis-regulatory elements were binding sites for the transcription factors (TFs) on DNA. Promoter analysis revealed that TC-rich repeats and a W1-box motif were both tightly related disease response motifs in Populus. Promoter analysis and target analysis of miRNAs also revealed that some TFs regulate their activation/repression. Furthermore, a feedback regulatory network in the pathological development of poplar stem canker is provided. The results confirm that miRNA pathways regulate gene expression during the pathological development of plant disease, and provide new insights into understanding the onset and development of poplar stem canker. PMID:23028709

Zhao, Jia-Ping; Jiang, Xiao-Ling; Zhang, Bing-Yu; Su, Xiao-Hua

2012-01-01

8

Canker Sores  

MedlinePLUS

... You can get them on or under the tongue and on the inside of the cheeks and lips — the parts of the mouth that can move. They usually pop up alone, but sometimes they show up in small clusters. Signs It's a Canker Sore Your mouth might tingle or burn before a canker sore appears. Soon, a small ...

9

Canker sore  

MedlinePLUS

Aphthous ulcer; Ulcer - aphthous ... Canker sores are a common form of mouth ulcer . They may occur with viral infections. In some ... spots or bump that develops into an open ulcer White or yellow center Small size (most often ...

10

Progeny differences of hinoki ( Chamaecyparis obtusa ) and sawara ( C. pisifera ) against resinous stem canker disease and spatial distribution of damage (disease severity) in a progeny test  

Microsoft Academic Search

The incidence and severity of resinous stem canker disease were investigated in hinoki (Chamaecyparis obtusa) and sawara (C. pisifera) at a progeny test located in Yamatsuri Town, Fukushima Prefecture, Japan. Symptoms of the disease were observed in 307 trees\\u000a out of 933 investigated trees (32.9%). The damage was more severe on lower slopes than on upper slopes, indicating that micro-environmental

Makoto Takahashi; Minoru Mukouda; Kenji Nishimura

1998-01-01

11

Ability of a Leptosphaeria maculans isolate to form stem cankers on Indian mustard ( Brassica juncea ) segregates as a single locus  

Microsoft Academic Search

Australian isolates of the blackleg fungusLeptosphaeria maculans, that form cankers on two Indian mustard (Brassica juncea) varieties (Stoke and Zaria) are described. This ability to form cankers on var. Stoke segregates as a single locus in both F1 and backcross progeny from a cross between twoL. maculans isolates.

Chang-Yong Chen; Kim M. Plummer; Barbara J. Howlett

1996-01-01

12

Alternaria redefined  

PubMed Central

Alternaria is a ubiquitous fungal genus that includes saprobic, endophytic and pathogenic species associated with a wide variety of substrates. In recent years, DNA-based studies revealed multiple non-monophyletic genera within the Alternaria complex, and Alternaria species clades that do not always correlate to species-groups based on morphological characteristics. The Alternaria complex currently comprises nine genera and eight Alternaria sections. The aim of this study was to delineate phylogenetic lineages within Alternaria and allied genera based on nucleotide sequence data of parts of the 18S nrDNA, 28S nrDNA, ITS, GAPDH, RPB2 and TEF1-alpha gene regions. Our data reveal a Pleospora/Stemphylium clade sister to Embellisia annulata, and a well-supported Alternaria clade. The Alternaria clade contains 24 internal clades and six monotypic lineages, the assemblage of which we recognise as Alternaria. This puts the genera Allewia, Brachycladium, Chalastospora, Chmelia, Crivellia, Embellisia, Lewia, Nimbya, Sinomyces, Teretispora, Ulocladium, Undifilum and Ybotromyces in synonymy with Alternaria. In this study, we treat the 24 internal clades in the Alternaria complex as sections, which is a continuation of a recent proposal for the taxonomic treatment of lineages in Alternaria. Embellisia annulata is synonymised with Dendryphiella salina, and together with Dendryphiella arenariae, are placed in the new genus Paradendryphiella. The sexual genera Clathrospora and Comoclathris, which were previously associated with Alternaria, cluster within the Pleosporaceae, outside Alternaria s. str., whereas Alternariaster, a genus formerly seen as part of Alternaria, clusters within the Leptosphaeriaceae. Paradendryphiella is newly described, the generic circumscription of Alternaria is emended, and 32 new combinations and 10 new names are proposed. A further 10 names are resurrected, while descriptions are provided for 16 new Alternaria sections. Taxonomic novelties: New combinations - Alternaria abundans (E.G. Simmons) Woudenb. & Crous, Alternaria alternariae (Cooke) Woudenb. & Crous, Alternaria atra (Preuss) Woudenb. & Crous, Alternaria bornmuelleri (Magnus) Woudenb. & Crous, Alternaria botrytis (Preuss) Woudenb. & Crous, Alternaria caespitosa (de Hoog & C. Rubio) Woudenb. & Crous, Alternaria cantlous (Yong Wang bis & X.G. Zhang) Woudenb. & Crous, Alternaria caricis (E.G. Simmons) Woudenb. & Crous, Alternaria cinerea (Baucom & Creamer) Woudenb. & Crous, Alternaria didymospora (Munt.-Cvetk.) Woudenb. & Crous, Alternaria fulva (Baucom & Creamer) Woudenb. & Crous, Alternaria hyacinthi (de Hoog & P.J. Mull. bis) Woudenb. & Crous, Alternaria indefessa (E.G. Simmons) Woudenberg & Crous, Alternaria leptinellae (E.G. Simmons & C.F. Hill) Woudenb. & Crous, Alternaria lolii (E.G. Simmons & C.F. Hill) Woudenb. & Crous, Alternaria multiformis (E.G. Simmons) Woudenb. & Crous, Alternaria obclavata (Crous & U. Braun) Woudenb. & Crous, Alternaria obovoidea (E.G. Simmons) Woudenb. & Crous, Alternaria oudemansii (E.G. Simmons) Woudenb. & Crous, Alternaria oxytropis (Q. Wang, Nagao & Kakish.) Woudenb. & Crous, Alternaria penicillata (Corda) Woudenb. & Crous, Alternaria planifunda (E.G. Simmons) Woudenb. & Crous, Alternaria proteae (E.G. Simmons) Woudenb. & Crous, Alternaria scirpinfestans (E.G. Simmons & D.A. Johnson) Woudenb. & Crous, Alternaria scirpivora (E.G. Simmons & D.A. Johnson) Woudenb. & Crous, Alternaria septospora (Preuss) Woudenb. & Crous, Alternaria slovaca (Svob.-Pol., L. Chmel & Bojan.) Woudenb. & Crous, Alternaria subcucurbitae (Yong Wang bis & X.G. Zhang) Woudenb. & Crous, Alternaria tellustris (E.G. Simmons) Woudenb. & Crous, Alternaria tumida (E.G. Simmons) Woudenb. & Crous, Paradendryphiella salina (G.K. Sutherl.) Woudenb. & Crous, Paradendryphiella arenariae (Nicot) Woudenb. & Crous. New names - Alternaria aspera Woudenb. & Crous, Alternaria botryospora Woudenb. & Crous, Alternaria brassicae-pekinensis Woudenb. & Crous, Alternaria breviramosa Woudenb. & Crous, Alternaria chlamydosporigena Woudenb. & Crous, Alternaria concatenata

Woudenberg, J.H.C.; Groenewald, J.Z.; Binder, M.; Crous, P.W.

2013-01-01

13

Canker Sore (Aphthous Ulcer)  

MedlinePLUS

newsletter | contact Share | Canker Sore (Aphthous Ulcer) Information for adults A A A This image displays white-to-yellow lesions typical of apthous ulcers. Overview Canker sores (aphthous ulcers), ...

14

Canker Sores (For Parents)  

MedlinePLUS

... canker sores. Sodium lauryl sulfate (SLS), an ingredient in many toothpastes and mouthwashes, has been linked to canker sores and is thought to prolong the healing time of the sores. Even emotional stress could be a factor. One study of college students showed that they had more canker sores during ...

15

A canker of Limonium sp. caused by Phomopsis limonii sp. nov  

Microsoft Academic Search

A stem canker disease of a Limonium hybrid ‘Chorus Magenta’ was identified at several sites throughout the North Island of New Zealand. First symptoms included leaves of diseased plants turning yellow, often on one side of the leaf blades. Cankers developed blue?black discoloration, and dark fruiting bodies of a fungus were located below the epidermis of cankers on dying plants.

I. C. Harvey; E. R. Morgan; G. K. Burge

2000-01-01

16

First outbreak of pitch canker in a South African pine plantation  

Microsoft Academic Search

Fusarium circinatum, the causal agent of pitch canker, was first reported in South Africa in 1990 on Pinus patula seedlings in a nursery. Subsequent to this outbreak the pathogen has spread throughout South African pine nurseries causing\\u000a a serious root and collar rot disease of various Pinus spp. The stem canker disease on plantation trees that typifies pitch canker in

T. A. Coutinho; E. T. Steenkamp; K. Mongwaketsi; M. Wilmot; M. J. Wingfield

2007-01-01

17

Alternaria within the Pericarp of the Wheat Seed  

Microsoft Academic Search

IN 1951, Miss Hyde1 obtained from the basal internode (about 1-2 in. long) of flowering stems of Barsée wheat and from stems immediately below the inflorescence, under aseptic conditions in culture plates, Alternaria tenuis in 40 and 43 stems out of 70. In 1953, I2 published a note on the apparent symbiotic nature of Alternaria tennis within the pericarp of

S. R. Bose

1956-01-01

18

A Test of the Validity of Screening Poplar Clones for Long-Term Canker Disease Damage by Responses to Inoculation with Septoria Musiva  

Microsoft Academic Search

Summary Septoria musiva (S. musiva) causes a stem canker dis- ease that severely damages susceptible hybrid poplars in Eastern North America. An earlier field trial demonstrated the potential for short-term responses of poplar stems to inoculation with S. musiva to be predictive of long-term canker disease damage. In the summer of 2000, addition- al poplar clones primarily selected by a

J. E. Weiland; J. C. Stanosz; G. R. Stanosz

19

Citrus Canker: The Pathogen and Its Impact  

NSDL National Science Digital Library

This resource is a review article about the Citrus Canker, an introduced plant disease. The article contains detailed background and overview and includes information on (1) Citrus Canker strain diversity, identification, diagnosis and characterization; (2) the symptoms and infection Process; (3) the epidemiology; (4) the management for prevention and control of Citrus Canker; (5) and the social, political, and legal ramifications of regulatory policy.

Tim R. Gottwald (USDA;); James H. Graham (University of Florida;); Tim S. Schubert (Florida Department of Agriculture and Consumer Services;)

2002-08-12

20

Nonhost resistance of Arabidopsis thaliana against Alternaria alternata involves both pre- and postinvasive defenses but is collapsed by AAL-toxin in the absence of LOH2.  

PubMed

The tomato pathotype of Alternaria alternata causes Alternaria stem canker on tomato depending upon the production of the host-specific AAL-toxin. Host defense mechanisms to A. alternata, however, are largely unknown. Here, we elucidate some of the mechanisms of nonhost resistance to A. alternata using Arabidopsis mutants. Wild-type Arabidopsis showed either no symptoms or a hypersensitive reaction (HR) when inoculated with both strains of AAL-toxin-producing and non-producing A. alternata. Yet, when these Arabidopsis penetration (pen) mutants, pen2 and pen3, were challenged with both strains of A. alternata, fungal penetration was possible. However, further fungal development and conidiation were limited on these pen mutants by postinvasion defense with HR-like cell death. Meanwhile, only AAL-toxin-producing A. alternata could invade lag one homologue (loh)2 mutants, which have a defect in the AAL-toxin resistance gene, subsequently allowing the fungus to complete its life cycle. Thus, the nonhost resistance of Arabidopsis thaliana to A. alternata consists of multilayered defense systems that include pre-invasion resistance via PEN2 and PEN3 and postinvasion resistance. However, our study also indicates that the pathogen is able to completely overcome the multilayered nonhost resistance if the plant is sensitive to the AAL-toxin, which is an effector of the toxin-dependent necrotrophic pathogen A. alternata. PMID:23360532

Egusa, Mayumi; Miwa, Takuya; Kaminaka, Hironori; Takano, Yoshitaka; Kodama, Motoichiro

2013-07-01

21

Prediction of Long-Term Canker Disease Damage from the Responses of Juvenile Poplar Clones to Inoculation with Septoria musiva  

Microsoft Academic Search

Weiland, J. E., Stanosz, J. C., and Stanosz, G. R. 2003. Prediction of long-term canker disease damage from the responses of juvenile poplar clones to inoculation with Septoria musiva. Plant Dis. 87:1507-1514. Stem cankers caused by Septoria musiva severely limit production of susceptible hybrid poplars in eastern North America. A field experiment was conducted to determine whether short-term responses of

JoAnne C. Stanosz; Glen R. Stanosz

22

Injected Treatments for Management of Madrone Canker  

Microsoft Academic Search

Pacific madrone (Arbutus menziesii) has been experiencing a decline in the Puget Sound area, primarily as a result of a canker disease caused by the fungus Fusicoccum arbuti. Cultural methods such as prevention of stress and wounding are recommended to control canker diseases on trees. In addition to these, injected treatments can be used to protect valuable Pacific madrone trees

Marianne Elliott; Robert L. Edmonds

2008-01-01

23

Canker Sores (Aphthous Stomatitis or Recurrent Mouth Ulcers)  

MedlinePLUS

Canker Sores (Aphthous Stomatitis or Recurrent Mouth Ulcers) What Is It? Symptoms Diagnosis Expected Duration Prevention Treatment When To Call a Professional Prognosis Additional Info What Is It? Canker sores are ...

24

76 FR 81359 - European Larch Canker; Expansion of Regulated Areas  

Federal Register 2010, 2011, 2012, 2013

...301 [Docket No. APHIS-2011-0029] European Larch Canker; Expansion of Regulated...regulations by expanding the regulated area for European larch canker to include additional areas...prevent human- assisted transmission of European larch canker from infested areas to...

2011-12-28

25

Dynamics of Cryphonectria hypovirus infection in chestnut blight cankers.  

PubMed

Virulent strains of the chestnut blight fungus Cryphonectria parasitica cause lethal bark cankers on chestnut trees. Infection of C. parasitica with Cryphonectria hypovirus 1 in Europe biologically controls this disease, leading to nonlethal and inactive cankers. Unexpectedly, virus-free C. parasitica strains have been isolated from inactive cankers. In this study, we compared the virulence of virus-infected and virus-free C. parasitica strains isolated from either inactive or active cankers on chestnut seedlings and sprouts. In the seedling experiment, we assessed canker growth and seedling mortality. In the sprout experiment, we also assessed canker growth and made fungal reisolations to determine virus infection and immigration of foreign vegetative compatibility (vc) types over a period of 13 years in a coppice forest. Overall, the virulence of virus-free C. parasitica strains isolated from inactive versus active cankers did not differ. Significant differences were only attributed to virus infection. Virus infection and fungal strain composition in cankers changed over time. Foreign vc types immigrated into cankers and virus-free cankers became virus-infected within a few years. Most of the cankers were callused over time and became inactive. However, we observed that the virus did not always persist in these cankers. This study demonstrates that virus spread occurs effectively in European chestnut forests and that this biocontrol system is highly dynamic. PMID:24601984

Bryner, Sarah Franziska; Prospero, Simone; Rigling, Daniel

2014-09-01

26

Clinical Characteristics of Alternaria Keratitis  

PubMed Central

Purpose. Alternaria spp. are an uncommon cause of mycotic keratitis. Previous studies on Alternaria keratitis have generally been limited to case reports. We examined the clinical characteristics of Alternaria keratitis in this study. Methods. The characteristics and outcomes of 7 patients with culture-proven Alternaria keratitis treated in our hospital were compared with 25 previously reported cases. Results. The risk factors for Alternaria keratitis were trauma in 5 patients and soft contact lenses in 1 patient. Six patients with early diagnosis (<2 weeks) were cured with medical antimicrobial treatment; a patch graft was required in 1 patient with perforation. When incorporated with previous reports on Alternaria keratitis (n = 32), 14 (44%) infections followed trauma, 10 (31%) were associated with preexisting corneal disease or previous ocular surgery, and 5 (16%) occurred in soft contact lens wearers. Successful medical treatment was achieved in 23 (72%) patients, including 10 out of 21 eyes (48%) treated with natamycin and/or amphotericin B. Therapeutic penetrating keratoplasty was performed in 9 (28%) cases. Conclusions. Alternaria keratitis is generally associated with specific risk factors and responds to medical treatment when early diagnosis is performed and prompt antifungal treatment is initiated. PMID:24778867

Lin, Hsin-Chiung; Chen, Phil Y. F.; Ma, David H. K.; Tan, Hsin-Yuan

2014-01-01

27

Fusarium circinatum and pitch canker of Pinus in Colombia E. T. Steenkamp & C. A. Rodas & M. Kvas &  

E-print Network

trees in plantations. Symptoms on seedlings included collar and root disease while shoot dieback and resinous stem cankers were found on trees in plantations. The aim of this study was to isolate and identify Pinus species in Haiti (Hepting and Roth 1953), Japan (Kobayashi and Muramoto 1989), Korea (Woo et al

28

Citrus Canker: The Pathogen and Its Impact  

NSDL National Science Digital Library

This Web site, currently featured on the home page of the American Phytopathological Society, contains a research report regarding the Asiatic citrus canker that has had devastating effects on Florida's citrus industry. The report, in a journal article format, thoroughly relates the natural history and current status of the disease, as well as detailing the methods and results of the (primarily genetic) experiments conducted in this study. One of the most appealing features of this Web site is the quality of the photos within the report. These photos can be viewed separately from the report in a slide show. While navigating this site is relatively straightforward, the lack of a table of contents can make finding your place in the body of the text somewhat confusing.

2002-01-01

29

Cryphonectria canker on Tibouchina in South Africa Henrietta MYBURG1  

E-print Network

Cryphonectria canker on Tibouchina in South Africa Henrietta MYBURG1 , Marieka GRYZENHOUT2 , Ronald, University of Pretoria, Pretoria, 0002, South Africa. 2 Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria, 0002, South Africa. 3 Forestry and Agricultural Biotechnology Institute

30

Increased risk of pitch canker to Australasia under climate change  

Microsoft Academic Search

Pitch canker is a varied and complex disease of Pinus species. Despite the establishment of this disease in many countries, it has been difficult to predict how Fusarium circinatum would behave if introduced into Australia or New Zealand. To understand the potential risk this pathogen poses to the forest\\u000a industries in Australasia, the process-oriented niche modelling program CLIMEX was used

Rebecca J. Ganley; Michael S. Watt; Darren J. Kriticos; Anna J. M. Hopkins; Lucy K. Manning

2011-01-01

31

Stems  

NSDL National Science Digital Library

Some mature plants can produce new plants by cutting a piece of stem off of the original plant. Most members of the mint family and ivy family can do this readily. The new plant will grow its own root system.

Olivia Worland (Purdue University;Biological Sciences)

2008-06-03

32

Tenuazonic Acid, a Toxin Produced by Alternaria alternata1  

PubMed Central

Fifty-seven of 87 isolates of Alternaria alternata (Fr) Keissler grown on autoclaved, moist corn-rice substrate and fed to rats were lethal. The major toxin produced was isolated and characterized as tenuazonic acid. Twenty of 23 toxigenic Alternaria isolates examined produced tenuazonic acid. No tenuazonic acid could be detected in either of the field samples of sorghum or blackeyed peas, which were heavily invaded by Alternaria. PMID:5063203

Meronuck, R. A.; Steele, J. A.; Mirocha, C. J.; Christensen, C. M.

1972-01-01

33

Over-expression of the Arabidopsis NPR1 gene in citrus increases resistance to citrus canker  

Microsoft Academic Search

Citrus canker, caused by the bacterial pathogen Xanthomonas citri subsp. citri (Xcc), is a serious leaf and fruit spotting disease affecting many important citrus cultivars including grapefruit and certain\\u000a sweet oranges. Currently, efficacious and economical disease control measures for highly susceptible citrus cultivars are\\u000a lacking. Development of commercial cultivars with greater field resistance to citrus canker is the optimum strategy

Xudong Zhang; Marta I. Francis; William O. Dawson; James H. Graham; Vladimir Orbovi?; Eric W. Triplett; Zhonglin Mou

2010-01-01

34

Thousand Canker Disease of Black Walnut Indiana Emergency Rule Indiana's Emergency Rule for Thousand Canker Disease of Black Walnut (TCD) will be effective  

E-print Network

Thousand Canker Disease of Black Walnut ­ Indiana Emergency Rule Indiana's Emergency Rule, and recently added Tennessee may not come into Indiana without an inspection at the point of origin by a state before they are to come into Indiana. The primary concern is Tennessee as it is the most likely source

35

Volatilization of Selenium by Alternaria alternata  

PubMed Central

Seleniferous water continues to be a serious problem to wildlife in the central valley of California. Water samples collected from Kesterson Reservoir, Peck Ranch, and Lost Hills evaporation pond facilities contained between 0.005 and 5 mg of Se per liter. The objective of this study was to isolate Se-methylating organisms in evaporation pond water and to assess, through enrichment and manipulation of their optimal growth parameters, the environmental factors which govern microbial Se methylation. Alternaria alternata was isolated as an active Se-methylating organism. The volatile product was identified as dimethylselenide. The effects of pH, temperature, Se substrates, and methyl donors on the ability of A. alternata to methylate Se were investigated in liquid medium containing 100 mg of Se per liter. The optimum pH and temperature for methylation were 6.5 and 30°C, respectively. Selenate and selenite were methylated more rapidly than selenium sulfide and various organic Se compounds (6-selenoguanosine, 6-selenoinosine, seleno-dl-methionine, and 6-selenopurine). l-Methionine and methyl cobalamine (0.1 ?M) stimulated dimethylselenide production. This study demonstrates that Se-methylating organisms are present in evaporation pond water and are capable of liberating substantial quantities of Se in the volatile dimethylselenide form. By determining the optimum environmental conditions which stimulate volatilization, it may be possible to design a way to remove Se from seleniferous water in situ. PMID:16347933

Thompson-Eagle, E. T.; Frankenberger, W. T.; Karlson, U.

1989-01-01

36

Oak tree canker disease supports arthropod diversity in a natural ecosystem.  

PubMed

Microorganisms have many roles in nature. They may act as decomposers that obtain nutrients from dead materials, while some are pathogens that cause diseases in animals, insects, and plants. Some are symbionts that enhance plant growth, such as arbuscular mycorrhizae and nitrogen fixation bacteria. However, roles of plant pathogens and diseases in natural ecosystems are still poorly understood. Thus, the current study addressed this deficiency by investigating possible roles of plant diseases in natural ecosystems, particularly, their positive effects on arthropod diversity. In this study, the model system was the oak tree (Quercus spp.) and the canker disease caused by Annulohypoxylon truncatum, and its effects on arthropod diversity. The oak tree site contained 44 oak trees; 31 had canker disease symptoms while 13 were disease-free. A total of 370 individual arthropods were detected at the site during the survey period. The arthropods belonged to 25 species, 17 families, and seven orders. Interestingly, the cankered trees had significantly higher biodiversity and richness compared with the canker-free trees. This study clearly demonstrated that arthropod diversity was supported by the oak tree canker disease. PMID:25288984

Lee, Yong-Bok; An, Su Jung; Park, Chung Gyoo; Kim, Jinwoo; Han, Sangjo; Kwak, Youn-Sig

2014-03-01

37

Oak Tree Canker Disease Supports Arthropod Diversity in a Natural Ecosystem  

PubMed Central

Microorganisms have many roles in nature. They may act as decomposers that obtain nutrients from dead materials, while some are pathogens that cause diseases in animals, insects, and plants. Some are symbionts that enhance plant growth, such as arbuscular mycorrhizae and nitrogen fixation bacteria. However, roles of plant pathogens and diseases in natural ecosystems are still poorly understood. Thus, the current study addressed this deficiency by investigating possible roles of plant diseases in natural ecosystems, particularly, their positive effects on arthropod diversity. In this study, the model system was the oak tree (Quercus spp.) and the canker disease caused by Annulohypoxylon truncatum, and its effects on arthropod diversity. The oak tree site contained 44 oak trees; 31 had canker disease symptoms while 13 were disease-free. A total of 370 individual arthropods were detected at the site during the survey period. The arthropods belonged to 25 species, 17 families, and seven orders. Interestingly, the cankered trees had significantly higher biodiversity and richness compared with the canker-free trees. This study clearly demonstrated that arthropod diversity was supported by the oak tree canker disease. PMID:25288984

Lee, Yong-Bok; An, Su Jung; Park, Chung Gyoo; Kim, Jinwoo; Han, Sangjo; Kwak, Youn-Sig

2014-01-01

38

A New Canker Disease of Apple, Pear, and Plum Rootstocks Caused by Diaporthe ambigua in South Africa  

E-print Network

A New Canker Disease of Apple, Pear, and Plum Rootstocks Caused by Diaporthe ambigua in South., Wingfield. B. D.. Wingfield. M. 1., and Calitz. F. J. 1996. A new canker disease of apple. pear, and plum was found to be the c:J.useof a newly recognized disease of apple. pear, and plum rootstocks in South Africa

39

Allergic bronchopulmonary mycosis due to Alternaria: Case report and review  

PubMed Central

While allergic bronchopulmonary aspergillosis and mycosis are well recognised, no cases have been described related to Alternaria spp. Alternaria is a common sensitising fungus in asthmatics and related to thunderstorm asthma. We report a case of an asthmatic who presented with worsening asthma control, mild eosinophilia on high dose inhaled corticosteroids (800 ?g/day), a total IgE of 3800 KIU/L, an Alternaria-specific IgE of 21.3 KUa/L and positive skin prick test, negative specific IgE and skin prick test to Aspergillus fumigatus, Penicillium spp., Cladosporium spp., Trichophyton spp. and a normal CT scan of the thorax. He responded well to a short course of oral prednisolone and then oral itraconazole, given over 17 months but relapsed 1 month after stopping it. PMID:24371728

Singh, Bhagteshwar; Denning, David W.

2012-01-01

40

Toxigenic profile and AFLP variability of Alternaria alternata and Alternaria infectoria occurring on wheat  

PubMed Central

The objectives of this study were to evaluate the ability to produce alternariol (AOH), alternariol monomethyl ether (AME) and tenuazonic acid (TA) by A. alternata and A. infectoria strains recovered from wheat kernels obtained from one of the main production area in Argentina; to confirm using AFLPs molecular markers the identify of the isolates up to species level, and to evaluate the intra and inter-specific genetic diversity of these two Alternaria species. Among all the Alternaria strains tested (254), 84% of them were able to produce mycotoxins. The most frequent profile of toxin production found was the co-production of AOH and AME in both species tested. TA was only produced by strains of A. alternata. Amplified fragment polymorphism (AFLPs) analysis was applied to a set of 89 isolates of Alternaria spp (40 were A. infectoria and 49 were A. alternata) in order to confirm the morphological identification. The results showed that AFLPs are powerful diagnostic tool for differentiating between A. alternata and A. infectoria. Indeed, in the current study the outgroup strains, A. tenuissima was consistently classified. Characteristic polymorphic bands separated these two species regardless of the primer combination used. Related to intraspecific variability, A. alternata and A. infectoria isolates evaluated seemed to form and homogeneous group with a high degree of similarity among the isolates within each species. However, there was more scoreable polymorphism within A. alternata than within A. infectoria isolates. There was a concordance between morphological identification and separation up to species level using molecular markers. Clear polymorphism both within and between species showed that AFLP can be used to asses genetic variation in A. alternata and A. infectoria. The most important finding of the present study was the report on AOH and AME production by A. infectoria strains isolated from wheat kernels in Argentina on a semisynthetic media for the first time. Also, specific bands for A. alternata and A. infectoria have been identified; these may be useful for the design of specific PCR primers in order to differentiate these species and to detect them in cereals. PMID:24294236

Oviedo, Maria Silvina; Sturm, Maria Elena; Reynoso, Maria Marta; Chulze, Sofia Noemi; Ramirez, Maria Laura

2013-01-01

41

Nonseptic diseases associated with the hoof complex: keratoma, white line disease, canker, and neoplasia.  

PubMed

This article addresses nonseptic diseases associated with the hoof complex, namely keratoma, white line disease, canker, and neoplasia. Keratoma is an uncommon cause of lameness, which may be surgically removed. White line disease, a keratolytic process on the solar surface of the hoof, is treated with therapeutic farriery and resection of the hoof wall when appropriate. Equine canker is an infectious process that results in development of a chronic hypertrophy of the horn-producing tissues. Neoplasia involving the equine foot is rare, and melanoma is the most common type of neoplasm reported. PMID:22981198

Redding, W Rich; O'Grady, Stephen E

2012-08-01

42

Figure 1. Rapidly wilting black walnut in the final stage of thousand cankers  

E-print Network

in the area of "Lone Mountain", New Mexico (Lincoln County). In the 1992 catalog of Bark and Ambrosia Beetles gallery. Figure 3. Distribution of the walnut twig beetle. In green are states and the California county 1998. Pest Alert Walnut Twig Beetle and Thousand Cankers Disease of Black Walnut Within the past decade

43

Research Note Susceptibility of South African native conifers to the pitch canker pathogen,  

E-print Network

Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0002 occurs on Douglas fir (Pseudotsuga menzeisii). It causes pitch canker of mature trees and root and collar in South Africa (Wingfield et al., 2002). The South African forestry industry contributes significantly

44

Novel hosts of the Eucalyptus canker pathogen Chrysoporthe cubensis and a new Chrysoporthe species from Colombia  

Microsoft Academic Search

The pathogen Chrysoporthe cubensis (formerly Cryphonectria cubensis) is best known for the important canker disease that it causes on Eucalyptus species. This fungus is also a pathogen of Syzygium aromaticum (clove), which is native to Indonesia, and like Eucalyptus, is a member of Myrtaceae. Furthermore, C. cubensis has been found on Miconia spp. native to South America and residing in

Marieka GRYZENHOUT; Carlos A. RODAS; Julio MENA PORTALES; Paul CLEGG; Brenda D. WINGFIELD; Michael J. WINGFIELD

2006-01-01

45

The Eucalyptus canker pathogen Holocryphia eucalypti on Eucalyptus in New Zealand  

Microsoft Academic Search

Holocryphia eucalypti is an opportunistic canker pathogen of Eucalyptus and Corymbia spp. (Myrtaceae, Myrtales) in Australia and South Africa. It is also known in Australia on Tibouchina trees (Melastomataceae, Myrtales). Using DNA sequence comparisons and morphological characterisation, we show for the first\\u000a time that H. eucalypti is present in New Zealand on Eucalyptus spp.

M. GryzenhoutA; M. VermeulenB; M. DickC; M. J. WingfieldA

2010-01-01

46

Alternaria alternata, a new pathotype pathogenic to aphids  

Microsoft Academic Search

A fungus, identified as Alternaria alternata, was isolated from dying or dead aphids and proved to be pathogenic. It was isolated from different parts of Greece from aphid specimens on cultivated plants, ornamentals and weeds. In the laboratory, disease development started with the germination of spores on the insect integument and the subsequent growth of mycelium. The fungus formed apical

Ch. Christias; P. Hatzipapas; A. Dara; A. Kaliafas; G. Chrysanthis

2001-01-01

47

Citrus MAF1, a repressor of RNA polymerase III, binds the Xanthomonas citri canker elicitor PthA4 and suppresses citrus canker development.  

PubMed

Transcription activator-like (TAL) effectors from Xanthomonas species pathogens act as transcription factors in plant cells; however, how TAL effectors activate host transcription is unknown. We found previously that TAL effectors of the citrus canker pathogen Xanthomonas citri, known as PthAs, bind the carboxyl-terminal domain of the sweet orange (Citrus sinensis) RNA polymerase II (Pol II) and inhibit the activity of CsCYP, a cyclophilin associated with the carboxyl-terminal domain of the citrus RNA Pol II that functions as a negative regulator of cell growth. Here, we show that PthA4 specifically interacted with the sweet orange MAF1 (CsMAF1) protein, an RNA polymerase III (Pol III) repressor that controls ribosome biogenesis and cell growth in yeast (Saccharomyces cerevisiae) and human. CsMAF1 bound the human RNA Pol III and rescued the yeast maf1 mutant by repressing tRNA(His) transcription. The expression of PthA4 in the maf1 mutant slightly restored tRNA(His) synthesis, indicating that PthA4 counteracts CsMAF1 activity. In addition, we show that sweet orange RNA interference plants with reduced CsMAF1 levels displayed a dramatic increase in tRNA transcription and a marked phenotype of cell proliferation during canker formation. Conversely, CsMAF1 overexpression was detrimental to seedling growth, inhibited tRNA synthesis, and attenuated canker development. Furthermore, we found that PthA4 is required to elicit cankers in sweet orange leaves and that depletion of CsMAF1 in X. citri-infected tissues correlates with the development of hyperplastic lesions and the presence of PthA4. Considering that CsMAF1 and CsCYP function as canker suppressors in sweet orange, our data indicate that TAL effectors from X. citri target negative regulators of RNA Pol II and Pol III to coordinately increase the transcription of host genes involved in ribosome biogenesis and cell proliferation. PMID:23898043

Soprano, Adriana Santos; Abe, Valeria Yukari; Smetana, Juliana Helena Costa; Benedetti, Celso Eduardo

2013-09-01

48

Airborne fungal spores of Alternaria, meteorological parameters and predicting variables  

NASA Astrophysics Data System (ADS)

Alternaria is frequently found as airborne fungal spores and is recognized as an important cause of respiratory allergies. The aerobiological monitoring of fungal spores was performed using a Burkard volumetric spore traps. To establish predicting variables for daily and weakly spore counts, a stepwise multiple regression between spore concentrations and independent variables (meteorological parameters and lagged values from the series of spore concentrations: previous day or week concentration (Alt t - 1) and mean concentration of the same day or week in other years (C mean)) was made with data obtained during 2009-2011. Alternaria conidia are present throughout the year in the atmosphere of Tetouan, although they show important seasonal fluctuations. The highest levels of Alternaria spores were recorded during the spring and summer or autumn. Alternaria showed maximum daily values in April, May or October depending on year. When the spore variables of Alternaria, namely C mean and Alt t - 1, and meteorological parameters were included in the equation, the resulting R 2 satisfactorily predict future concentrations for 55.5 to 81.6 % during the main spore season and the pre-peak 2. In the predictive model using weekly values, the adjusted R 2 varied from 0.655 to 0.676. The Wilcoxon test was used to compare the results from the expected values and the pre-peak spore data or weekly values for 2012, indicating that there were no significant differences between series compared. This test showed the C mean, Alt t - 1, frequency of the wind third quadrant, maximum wind speed and minimum relative humidity as the most efficient independent variables to forecast the overall trend of this spore in the air.

Filali Ben Sidel, Farah; Bouziane, Hassan; del Mar Trigo, Maria; El Haskouri, Fatima; Bardei, Fadoua; Redouane, Abdelbari; Kadiri, Mohamed; Riadi, Hassane; Kazzaz, Mohamed

2014-05-01

49

Simultaneous production of glucose oxidase and catalase by Alternaria alternata  

Microsoft Academic Search

A number of factors affecting simultaneous production of cell-bound glucose oxidase and catalase by the fungus Alternaria alternata have been investigated. Consecutive optimization of the type and concentration of nitrogen and carbon source, the initial pH and growth temperature resulted in a simultaneous increase in glucose oxidase and catalase by 780% and 68% respectively. Two second-order equations, describing the combined

Konstantina-Anna Caridis; Paul Christakopoulos; Basil J. Macris

1991-01-01

50

High population diversity and increasing importance of the Eucalyptus stem canker pathogen, Teratosphaeria  

E-print Network

. In this study, the genetic diversity of three T. zuluensis populations from different regions in South China, Teratosphaeria zuluensis, in South China Shuai Fei Chen & Irene Barnes & Donald Chungu & Jolanda Roux & Michael J structure of T. zuluensis in China, Malawi and South Africa has suggested that T. zuluensis

51

Effect of plant growth promoting rhizobacteria on bacterial canker of tomato  

Microsoft Academic Search

Use of plant growth promoting rhizobacteria in managing bacterial canker disease of tomato was studied in the present work. Tomato seeds were treated with PGPR strains viz., Bacillus pumilus INR7, Bacillus pumilus SE34, Bacillus pumilus T4, Bacillus subtilis GBO3, Bacillus amyloliquefaciens IN937a and Brevibacillus brevis IPC11 were subjected for seed germination and seedling vigor. Among the PGPR strains tested, only

N Girish; S Umesha

2005-01-01

52

Effect of Lime on Criconemella xenoplax and Bacterial Canker in Two California Orchards 1  

Microsoft Academic Search

In a peach orchard with an initial soil pH of 4.9, preplant application of 0, 13.2, 18.2, 27.3, or 54.2 kg lime\\/tree site altered soil pH (range after 1 year = 4.8-7.3) but did not affect numbers of Criconemella xenoplax or tree circumference. Liming also failed to reduce the incidence of bacterial canker, which affected 17% of the trees by

T. UNDERWOOD; B. A. JAFFEE; P. VERDEGAAL; M. V. K. NORTON; W. K. ASAI; A. E. MULDOON; M. V. MCKENRY; H. FERRIS

1994-01-01

53

Antiproliferative, antifungal, and antibacterial activities of endophytic alternaria species from cupressaceae.  

PubMed

Recent research has shown the bioprospecting of endophytic fungi from Cupressaceae. Here, we further uncover that the healthy cypress plants such as Cupressus arizonica, Cupressus sempervirens var. cereiformis, and Thuja orientalis host highly bioactive endophytic Alternaria fungal species. Indeed, endophytic Alternaria alternata, Alternaria pellucida, and Alternaria tangelonis were recovered from healthy Cupressaceous trees. Biodiversity and bioactivity of recovered endophytic Alternaria species were a matter of biogeography and host identity. We further extracted such Alternaria's metabolites and highlighted their significant antiproliferative, growth inhibitory, and antibacterial activities against the model target fungus Pyricularia oryzae and the model pathogenic bacteria Bacillus sp., Erwinia amylovora, and Pseudomonas syringae. In vitro assays also indicated that endophytic Alternaria species significantly inhibited the growth of cypress fungal phytopathogens Diplodia seriata, Phaeobotryon cupressi, and Spencermartinsia viticola. In conclusion, since the recovered Alternaria species were originally reported as pathogenic and allergenic fungi, our findings suggest a possible ecological niche for them inside the foliar tissues of Cupressaceous trees. Moreover, in this study, the significant bioactivities of endophytic Alternaria species in association with Cupressaceae plant family are reported. PMID:24801337

Soltani, Jalal; Hosseyni Moghaddam, Mahdieh S

2014-09-01

54

Alternaria spores in the atmosphere of Sydney, Australia, and relationships with meteorological factors  

Microsoft Academic Search

Alternaria spores are found in the atmosphere in many locations around the world. They are significant from a human health perspective because they have been known to trigger allergic respiratory disease such as asthma and hay-fever. The presence of Alternaria spores in the atmosphere has been related to meteorological factors in past studies, but this has not been done previously

P. J. Stennett; P. J. Beggs

2004-01-01

55

Effect of citrus leaf-miner damage, mechanical damage and inoculum concentration on severity of symptoms of Asiatic citrus canker in Tahiti lime  

Microsoft Academic Search

Citriculture in São Paulo State, Brazil, is threatened by Asiatic citrus canker (Xanthomonas axonopodis pv. citri). The introduction of the Asian citrus leaf miner (Phyllocnistis citrella [CLM]) has resulted in an increase in the number of disease foci and has changed the spatial pattern of citrus canker symptomatic trees from strong aggregation to intermediate aggregation and random patterns. We evaluated

R. S. C. Christiano; M. Dalla Pria; W. C. Jesus Junior; J. R. P. Parra; L. Amorim; A. Bergamin Filho

2007-01-01

56

First Report of Nectria galligena Causing European Canker of Apple Trees in Ontario. A. R. Biggs, Agriculture Canada Research Station, Vineland Station, Ontario LOR 2EO. Plant  

E-print Network

First Report of Nectria galligena Causing European Canker of Apple Trees in Ontario. A. R. Biggs for publication 19 July 1985. European canker of apple (Malus domestics Borkh. 'MacIntosh') caused by Nectria includes the apple-growing region of central Ontario. Reference: Booth, C. Commonw. Mycol. Inst. Pap. 73

Biggs, Alan R.

57

Antifungal activity of some plant extracts on Alternaria alternata, the causal agent of alternaria leaf spot of potato.  

PubMed

Pure methanol (m) and methanol water (mw) extracts of 5 plants namely: peppermint, eucalyptus, lavandula, Russian knapweed and datura were screened for their antifungal ability against Alternaria alternata, the causal agent of Alternaria leaf spot of potato at 5, 10 and 15% concentrations in vitro. Fungicide mancozeb 0.2% was also used for better comparison. Poisoned food technique and spore germination assay method were used to evaluate the antifungal efficacy of plant extracts. Present findings showed that methanol extracts of eucalyptus, peppermint and lavandula had impressive antifungal effects in inhibiting the mycelial growth as well as spore germination of the pathogen. It was also found that methanol extracts were quite more effective than methanol water extracts in this regard. Methanol extracts of peppermint (15%), lavandula (15%), peppermint (10%) and eucalyptus (15%) demonstrated promising ability in inhibiting the mycelial growth of A. alternata by 0.13, 0.40, 0.43 and 0.50 cm, mycelial growth respectively, while majority of methanol water extracts had either less or no effects in this connection. Spore germination of A. alternata was prominently reduced by methanol extracts, while those of methanol water extracts had very less effects in this regard. Mancozeb (0.2%), methanol extracts of eucalyptus (15%) and peppermint (10%) by 2, 6 and 7% spore germination were best, while methanol water extracts of datura 10, 15 and 5%, lavandula 15 and 10% and also Russian knapweed 5% represented no effect and by 91, 89, 87, 87, 85 and 85% spore germination were at par with control. Findings from this study confirmed that plant extracts can be used as less hazardous natural fungicides in controlling plant pathogenic fungi, thus reducing the dependence on the synthetic fungicides. Methanol extracts of peppermint, eucalyptus and lavandula might be promising materials for natural formulations in controlling Alternaria leaf spot of potato in the field. PMID:21313872

Zaker, M; Mosallanejad, H

2010-11-01

58

Effect of Lime on Criconemella xenoplax and Bacterial Canker in Two California Orchards.  

PubMed

In a peach orchard with an initial soil pH of 4.9, preplant application of 0, 13.2, 18.2, 27.3, or 54.2 kg lime/tree site altered soil pH (range after 1 year = 4.8-7.3) but did not affect numbers of Criconemella xenoplax or tree circumference. Liming also failed to reduce the incidence of bacterial canker, which affected 17% of the trees by the sixth year after planting. Four years after planting, numbers of C. xenoplax exceeded 400/100 cm(3) soil, regardless of treatment. Trees with higher densities of C. xenoplax had a higher incidence of canker. The nematophagous fungus Hirsutella rhossiliensis was not detected until the fourth year. Thereafter, the incidence of H. rhossiliensis and percentage C. xenoplax parasitized by H. rhossiliensis increased, but the increases lagged behind increases in numbers of nematodes. In an almond orchard with an initial soil pH of 4.6, preplant application of 0, 6.4, 12.8, or 25.0 kg lime/tree site altered soil pH (range after 1 year = 4.7-7.1). Numbers of C. xenoplax remained low (<20/100 cm(3) soil), whereas numbers of Paratylenchus sp. increased to high levels (>500/100 cm(3) soil), regardless of treatment. Low levels (<20/100 cm(3) soil) of H. rhossiliensis -parasitized Paratylenchus sp. were detected. No bacterial canker occurred, but tree circumference was greater after 6 years if soil pH was intermediate (6.0-7.0). PMID:19279934

Underwood, T; Jaffee, B A; Verdegaal, P; Norton, M V; Asai, W K; Muldoon, A E; McKenry, M V; Ferris, H

1994-12-01

59

Effect of Lime on Criconemella xenoplax and Bacterial Canker in Two California Orchards  

PubMed Central

In a peach orchard with an initial soil pH of 4.9, preplant application of 0, 13.2, 18.2, 27.3, or 54.2 kg lime/tree site altered soil pH (range after 1 year = 4.8-7.3) but did not affect numbers of Criconemella xenoplax or tree circumference. Liming also failed to reduce the incidence of bacterial canker, which affected 17% of the trees by the sixth year after planting. Four years after planting, numbers of C. xenoplax exceeded 400/100 cm³ soil, regardless of treatment. Trees with higher densities of C. xenoplax had a higher incidence of canker. The nematophagous fungus Hirsutella rhossiliensis was not detected until the fourth year. Thereafter, the incidence of H. rhossiliensis and percentage C. xenoplax parasitized by H. rhossiliensis increased, but the increases lagged behind increases in numbers of nematodes. In an almond orchard with an initial soil pH of 4.6, preplant application of 0, 6.4, 12.8, or 25.0 kg lime/tree site altered soil pH (range after 1 year = 4.7-7.1). Numbers of C. xenoplax remained low (<20/100 cm³ soil), whereas numbers of Paratylenchus sp. increased to high levels (>500/100 cm³ soil), regardless of treatment. Low levels (<20/100 cm³ soil) of H. rhossiliensis -parasitized Paratylenchus sp. were detected. No bacterial canker occurred, but tree circumference was greater after 6 years if soil pH was intermediate (6.0-7.0). PMID:19279934

Underwood, T.; Jaffee, B. A.; Verdegaal, P.; Norton, M. V. K.; Asai, W. K.; Muldoon, A. E.; McKenry, M. V.; Ferris, H.

1994-01-01

60

Dieback and sooty canker of Ficus trees in Egypt and its control.  

PubMed

This study was designed to throw lights on dieback and canker disease on urban trees of Ficus sp. in Egypt, its causal pathogens and disease control. Diseased samples were collected from five locations. Pathogenicity test was done on one year old of three different healthy seedlings of Ficus trees (Ficus benghalensis, Ficu snitida and Ficus hawaii). Lasiodiplodia theobromae and Phomopsis sp. were consistently isolated from infected tissues and were pathogenic. The fungicides Antracol Combi and Topsin M 70 provided effective control of the infection. Accordingly, protecting ficus trees from diseases threating is considered a major goal to attain their benefits. PMID:24897790

Abo Rehab, M E A; Rashed, M F; Ammar, M I; El-Morsy, S A

2014-02-01

61

Alternaria Inhibits Double-stranded RNA-Induced Cytokines Productions through TLR3  

PubMed Central

Background Fungi may be involved in asthma and chronic rhinosinusitis (CRS). PBMCs from CRS patients produce IL-5, IL-13 and INF-? by Alternaria. In addition, Alternaria produces potent Th2-like adjuvant effects in the airway. Therefore, we hypothesized that Alternaria may inhibit Th1-type defense mechanisms against virus infection. Methods Dendritic cells (DCs) were generated from mouse bone marrow. The functional responses were assessed by expression of cell surface molecules by FACS (MHC Class II, CD40, CD80, CD86 and OX40L. Production of IL-6, IP-10, I-TAC and IFN -? were measured by ELISA. TLR3 mRNA and protein expression were detected by quantitative Real time-PCR and Western blot. Results Alternaria and poly I:C enhanced cell surface expression of MHC Class II, CD40, CD80, CD86 and OX40L, and IL-6 production in a concentration-dependent manner. However, Alternaria significantly inhibited IP-10, I-TAC and IFN-? production induced by viral double-stranded RNA (dsRNA)-mimic poly I:C. TLR3 mRNA expression and protein production by poly I:C were significantly inhibited by Alternaria. These reactions are likely caused by heat-stable factor(s) in Alternaria extract with >100 kDa molecular mass. Conclusion These findings suggest that fungus, Alternaria may inhibit production of IFN-? and other cytokines by DCs by suppressing TLR3 expression. These results indicate that Alternaria may inhibit host innate immunity against virus infection. PMID:23711857

Wada, Kota; Kobayashi, Takao; Matsuwaki, Yoshinori; Moriyama, Hiroshi; Kita, Hirohito

2014-01-01

62

Comparison of Alternaria tenuis extracts prepared from different raw materials.  

PubMed

Alternaria extracts, prepared from three different sources under the same conditions, were compared by several biochemical/immunochemical methods. Two raw materials (A,G) contained mostly mycelia. The third raw material (C) contained mycelia (35%) and spores (65%). Extracts A and G were different in total allergenic potency, antigen/allergen pattern, and in the Alt 1 content. Extract C was of similar total allergenic potency as extract A but showed a somewhat different antigen/allergen pattern and a different Alt 1 content. Although there were some compositional differences among the extracts, all extracts regardless of source materials (spores and mycelia) demonstrated strong RAST inhibition activity and parallelism of the inhibition curves. PMID:2596763

Wahl, R; Oliver, J D; Hauck, P R; Winter, H G; Maasch, H J

1989-12-01

63

40 CFR 180.1256 - Alternaria destruens strain 059; exemption from the requirement of a tolerance.  

Code of Federal Regulations, 2011 CFR

...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions...tolerance is established for residues of the microbial pesticide Alternaria destruens Strain 059...

2011-07-01

64

40 CFR 180.1256 - Alternaria destruens strain 059; exemption from the requirement of a tolerance.  

Code of Federal Regulations, 2010 CFR

...ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions...tolerance is established for residues of the microbial pesticide Alternaria destruens Strain 059...

2010-07-01

65

A Polymerase Chain Reaction-Based Method to Specifically Detect Alternaria alternata Apple Pathotype (A. mali), the Causal Agent of Alternaria Blotch of Apple.  

PubMed

ABSTRACT Alternaria alternata apple pathotype (previously A. mali) causes Alternaria blotch on susceptible apple cultivars through the production of a host-specific toxin, AM-toxin. Identification of some Alternaria species, especially those that produce host-specific toxins, has been extremely difficult due to a high level of variability which extends even to nonpathogenic isolates. We have recently cloned and characterized a gene (AMT) that plays a crucial role in AM-toxin biosynthesis and demonstrated that it is only present in isolates of A. alternata apple pathotype. Using primers designed for the AMT gene, we developed a polymerase chainreaction-based method to specifically detect AM-toxin producing isolates of A. alternata apple pathotype. PMID:18944521

Johnson, R D; Johnson, L; Kohmoto, K; Otani, H; Lane, C R; Kodama, M

2000-09-01

66

Alternaria alternata from oilseed rape: mycotoxin production, and toxicity to Artemia salina larvae and rape seedlings  

Microsoft Academic Search

Summary  A survey, carried out in Southern Italy on fungi colonizing oilseed rape (Brassicae napua L subspoleifera DC) in the field, showedAlternaria alternata (Fries) Keissler as one of the predominant species. 11 strains ofAlternaria alternata isolated from oilseed rape were cultured on rice to test the ability to produce mycotoxins. All strains produced mycotoxins,\\u000a including tenuazonic acid (up to 12,000mg\\/kg), alternariol

A Visconti; A Sibilia; C Sabia

1992-01-01

67

Barrier Disrupting Effects of Alternaria Alternata Extract on Bronchial Epithelium from Asthmatic Donors  

PubMed Central

Sensitization and exposure to the allergenic fungus Alternaria alternata has been associated with increased risk of asthma and asthma exacerbations. The first cells to encounter inhaled allergens are epithelial cells at the airway mucosal surface. Epithelial barrier function has previously been reported to be defective in asthma. This study investigated the contribution of proteases from Alternaria alternata on epithelial barrier function and inflammatory responses and compared responses of in vitro cultures of differentiated bronchial epithelial cells derived from severely asthmatic donors with those from non-asthmatic controls. Polarised 16HBE cells or air-liquid interface (ALI) bronchial epithelial cultures from non-asthmatic or severe asthmatic donors were challenged apically with extracts of Alternaria and changes in inflammatory cytokine release and transepithelial electrical resistance (TER) were measured. Protease activity in Alternaria extracts was characterised and the effect of selectively inhibiting protease activity on epithelial responses was examined using protease inhibitors and heat-treatment. In 16HBE cells, Alternaria extracts stimulated release of IL-8 and TNF?, with concomitant reduction in TER; these effects were prevented by heat-treatment of the extracts. Examination of the effects of protease inhibitors suggested that serine proteases were the predominant class of proteases mediating these effects. ALI cultures from asthmatic donors exhibited a reduced IL-8 response to Alternaria relative to those from healthy controls, while neither responded with increased thymic stromal lymphopoietin (TSLP) release. Only cultures from asthmatic donors were susceptible to the barrier-weakening effects of Alternaria. Therefore, the bronchial epithelium of severely asthmatic individuals may be more susceptible to the deleterious effects of Alternaria. PMID:24009658

Blume, Cornelia; Swindle, Emily J.; Jayasekera, Nivenka P.; Dennison, Patrick W.; Shamji, Betty W. H.; Edwards, Matthew J.; Holgate, Stephen T.; Howarth, Peter H.; Davies, Donna E.

2013-01-01

68

ATP release and Ca2+ signalling by human bronchial epithelial cells following Alternaria aeroallergen exposure  

PubMed Central

Exposure of human bronchial epithelial (HBE) cells from normal and asthmatic subjects to extracts from Alternaria alternata evoked a rapid and sustained release of ATP with greater efficacy observed in epithelial cells from asthmatic patients. Previously, Alternaria allergens were shown to produce a sustained increase in intracellular Ca2+ concentration ([Ca2+]i) that was dependent on the coordinated activation of specific purinergic receptor (P2Y2 and P2X7) subtypes. In the present study, pretreatment with a cell-permeable Ca2+-chelating compound (BAPTA-AM) significantly inhibited ATP release, indicating dependency on [Ca2+]i. Alternaria-evoked ATP release exhibited a greater peak response and a slightly lower EC50 value in cells obtained from asthmatic donors compared to normal control cells. Furthermore, the maximum increase in [Ca2+]i resulting from Alternaria treatment was greater in cells from asthmatic patients compared to normal subjects. The vesicle transport inhibitor brefeldin A and BAPTA-AM significantly blocked Alternaria-stimulated incorporation of fluorescent lipid (FM1-43)-labelled vesicles into the plasma membrane and ATP release. In addition, inhibiting uptake of ATP into exocytotic vesicles with bafilomycin also reduced ATP release comparable to the effects of brefeldin A and BAPTA-AM. These results indicate that an important mechanism for Alternaria-induced ATP release is Ca2+ dependent and involves exocytosis of ATP. Serine and cysteine protease inhibitors also reduced Alternaria-induced ATP release; however, the sustained increase in [Ca2+]i typically observed following Alternaria exposure appeared to be independent of protease-activated receptor (PAR2) stimulation. PMID:23858006

O'Grady, Scott M; Patil, Nandadavi; Melkamu, Tamene; Maniak, Peter J; Lancto, Cheryl; Kita, Hirohito

2013-01-01

69

Identification and characterization of microsatellite from Alternaria brassicicola to assess cross-species transferability and utility as a diagnostic marker.  

PubMed

Alternaria blight caused by Alternaria brassicicola (Schwein.) Wiltshire and A. brassicae (Berk.) Sacc., is one of the most important disease of rapeseed-mustard, characterized by the formation of spots on leaves, stem, and siliquae with premature defoliation and stunting of growth. These two species are very difficult to differentiate based on disease symptoms or spore morphology. Therefore, the aim of present investigation was to identify and characterize transferable microsatellite loci from A. brassicicola to A. brassicae for the development of diagnostic marker. A total of 8,457 microsatellites were identified from transcript sequences of A. brassicicola. The average density of microsatellites was one microsatellite per 1.94 kb of transcript sequence screened. The most frequent repeat was tri-nucleotide (74.03 %), whereas penta-nucleotide (1.14 %) was least frequent. Among amino acids, arginine (13.11 %) showed maximum abundance followed by lysine (10.11 %). A total of 32 alleles were obtained across the 31 microsatellite loci for the ten isolates of A. brassicicola. In cross-species amplifications, 5 of the 31 markers amplified the corresponding microsatellite regions in twenty isolates of A. brassicae and showed monomorphic banding pattern. Microsatellite locus ABS28 was highly specific for A. brassicicola, as no amplification was observed from twenty-nine other closely related taxa. Primer set, ABS28F/ABS28R, amplified a specific amplicon of 380 bp from all A. brassicicola isolates. Standard curves were generated for A. brassicicola isolate using SYBR Green I fluorescent dye for detection of amplification in real-time PCR assay. The lowest detection limit of assay was 0.01 ng. Thus, the primer set can be used as diagnostic marker to discriminate and diagnose A. brassicicola from synchronously occurring fungus, A. brassicae associated with rapeseed and mustard. PMID:25048820

Singh, Ruchi; Kumar, Sudheer; Kashyap, Prem Lal; Srivastava, Alok Kumar; Mishra, Sanjay; Sharma, Arun Kumar

2014-11-01

70

STEM, STEM Education, STEMmania  

ERIC Educational Resources Information Center

In this article, the author introduces integrative STEM (science, technology, engineering, and/or mathematics) education and discusses the importance of the program. The notion of integrative STEM education includes approaches that explore teaching and learning between/among any two or more of the STEM subject areas, and/or between a STEM subject…

Sanders, Mark

2009-01-01

71

Canker Sores  

MedlinePLUS

... Journal Newsletters Latest News 2015 AAOM Call for Abstract Submissions AAOM Offers Clinical Practice Statements Upcoming Events 2014 Fall Meeting - Duluth, GA AAOM/AAOMP 2015 Annual Meeting 2016 ...

72

Delimiting cryptic pathogen species causing apple Valsa canker with multilocus data  

PubMed Central

Fungal diseases are posing tremendous threats to global economy and food safety. Among them, Valsa canker, caused by fungi of Valsa and their Cytospora anamorphs, has been a serious threat to fruit and forest trees and is one of the most destructive diseases of apple in East Asia, particularly. Accurate and robust delimitation of pathogen species is not only essential for the development of effective disease control programs, but also will advance our understanding of the emergence of plant diseases. However, species delimitation is especially difficult in Valsa because of the high variability of morphological traits and in many cases the lack of the teleomorph. In this study, we delimitated species boundary for pathogens causing apple Valsa canker with a multifaceted approach. Based on three independent loci, the internal transcribed spacer (ITS), ?-tubulin (Btu), and translation elongation factor-1 alpha (EF1?), we inferred gene trees with both maximum likelihood and Bayesian methods, estimated species tree with Bayesian multispecies coalescent approaches, and validated species tree with Bayesian species delimitation. Through divergence time estimation and ancestral host reconstruction, we tested the possible underlying mechanisms for fungal speciation and host-range change. Our results proved that two varieties of the former morphological species V. mali represented two distinct species, V. mali and V. pyri, which diverged about 5 million years ago, much later than the divergence of their preferred hosts, excluding a scenario of fungi–host co-speciation. The marked different thermal preferences and contrasting pathogenicity in cross-inoculation suggest ecological divergences between the two species. Apple was the most likely ancestral host for both V. mali and V. pyri. Host-range expansion led to the occurrence of V. pyri on both pear and apple. Our results also represent an example in which ITS data might underestimate species diversity. PMID:24834333

Wang, Xuli; Zang, Rui; Yin, Zhiyuan; Kang, Zhensheng; Huang, Lili

2014-01-01

73

Identification of Bacteriophages for Biocontrol of the Kiwifruit Canker Phytopathogen Pseudomonas syringae pv. actinidiae  

PubMed Central

Pseudomonas syringae pv. actinidiae is a reemerging pathogen which causes bacterial canker of kiwifruit (Actinidia sp.). Since 2008, a global outbreak of P. syringae pv. actinidiae has occurred, and in 2010 this pathogen was detected in New Zealand. The economic impact and the development of resistance in P. syringae pv. actinidiae and other pathovars against antibiotics and copper sprays have led to a search for alternative management strategies. We isolated 275 phages, 258 of which were active against P. syringae pv. actinidiae. Extensive host range testing on P. syringae pv. actinidiae, other pseudomonads, and bacteria isolated from kiwifruit orchards showed that most phages have a narrow host range. Twenty-four were analyzed by electron microscopy, pulse-field gel electrophoresis, and restriction digestion. Their suitability for biocontrol was tested by assessing stability and the absence of lysogeny and transduction. A detailed host range was performed, phage-resistant bacteria were isolated, and resistance to other phages was examined. The phages belonged to the Caudovirales and were analyzed based on morphology and genome size, which showed them to be representatives of Myoviridae, Podoviridae, and Siphoviridae. Twenty-one Myoviridae members have similar morphologies and genome sizes yet differ in restriction patterns, host range, and resistance, indicating a closely related group. Nine of these Myoviridae members were sequenced, and each was unique. The most closely related sequenced phages were a group infecting Pseudomonas aeruginosa and characterized by phages JG004 and PAK_P1. In summary, this study reports the isolation and characterization of P. syringae pv. actinidiae phages and provides a framework for the intelligent formulation of phage biocontrol agents against kiwifruit bacterial canker. PMID:24487530

Frampton, Rebekah A.; Taylor, Corinda; Holguín Moreno, Angela V.; Visnovsky, Sandra B.; Petty, Nicola K.; Pitman, Andrew R.

2014-01-01

74

Identification of bacteriophages for biocontrol of the kiwifruit canker phytopathogen Pseudomonas syringae pv. actinidiae.  

PubMed

Pseudomonas syringae pv. actinidiae is a reemerging pathogen which causes bacterial canker of kiwifruit (Actinidia sp.). Since 2008, a global outbreak of P. syringae pv. actinidiae has occurred, and in 2010 this pathogen was detected in New Zealand. The economic impact and the development of resistance in P. syringae pv. actinidiae and other pathovars against antibiotics and copper sprays have led to a search for alternative management strategies. We isolated 275 phages, 258 of which were active against P. syringae pv. actinidiae. Extensive host range testing on P. syringae pv. actinidiae, other pseudomonads, and bacteria isolated from kiwifruit orchards showed that most phages have a narrow host range. Twenty-four were analyzed by electron microscopy, pulse-field gel electrophoresis, and restriction digestion. Their suitability for biocontrol was tested by assessing stability and the absence of lysogeny and transduction. A detailed host range was performed, phage-resistant bacteria were isolated, and resistance to other phages was examined. The phages belonged to the Caudovirales and were analyzed based on morphology and genome size, which showed them to be representatives of Myoviridae, Podoviridae, and Siphoviridae. Twenty-one Myoviridae members have similar morphologies and genome sizes yet differ in restriction patterns, host range, and resistance, indicating a closely related group. Nine of these Myoviridae members were sequenced, and each was unique. The most closely related sequenced phages were a group infecting Pseudomonas aeruginosa and characterized by phages JG004 and PAK_P1. In summary, this study reports the isolation and characterization of P. syringae pv. actinidiae phages and provides a framework for the intelligent formulation of phage biocontrol agents against kiwifruit bacterial canker. PMID:24487530

Frampton, Rebekah A; Taylor, Corinda; Holguín Moreno, Angela V; Visnovsky, Sandra B; Petty, Nicola K; Pitman, Andrew R; Fineran, Peter C

2014-04-01

75

Novel insights into the genomic basis of citrus canker based on the genome sequences of two strains of Xanthomonas fuscans subsp. aurantifolii  

PubMed Central

Background Citrus canker is a disease that has severe economic impact on the citrus industry worldwide. There are three types of canker, called A, B, and C. The three types have different phenotypes and affect different citrus species. The causative agent for type A is Xanthomonas citri subsp. citri, whose genome sequence was made available in 2002. Xanthomonas fuscans subsp. aurantifolii strain B causes canker B and Xanthomonas fuscans subsp. aurantifolii strain C causes canker C. Results We have sequenced the genomes of strains B and C to draft status. We have compared their genomic content to X. citri subsp. citri and to other Xanthomonas genomes, with special emphasis on type III secreted effector repertoires. In addition to pthA, already known to be present in all three citrus canker strains, two additional effector genes, xopE3 and xopAI, are also present in all three strains and are both located on the same putative genomic island. These two effector genes, along with one other effector-like gene in the same region, are thus good candidates for being pathogenicity factors on citrus. Numerous gene content differences also exist between the three cankers strains, which can be correlated with their different virulence and host range. Particular attention was placed on the analysis of genes involved in biofilm formation and quorum sensing, type IV secretion, flagellum synthesis and motility, lipopolysacharide synthesis, and on the gene xacPNP, which codes for a natriuretic protein. Conclusion We have uncovered numerous commonalities and differences in gene content between the genomes of the pathogenic agents causing citrus canker A, B, and C and other Xanthomonas genomes. Molecular genetics can now be employed to determine the role of these genes in plant-microbe interactions. The gained knowledge will be instrumental for improving citrus canker control. PMID:20388224

2010-01-01

76

Nitrogen inhibition of mycotoxin production by Alternaria alternata.  

PubMed Central

Alternaria alternata produces the polyketides alternariol (AOH) and alternariol monomethyl ether (AME) during the stationary growth phase. Addition of 12 mM NaNO3 to the cultures before initiation of polyketide production reduced the AOH and AME content to 5 to 10% of that of controls. Glutamate and urea also reduced AOH and AME accumulation, whereas increasing the ionic strength did not affect the polyketide content. Adding NaNO3 after polyketide production had started did not inhibit further AOH accumulation, although over 90% of the added NO3- disappeared from the medium within 24 h. Activity of an AME-synthesizing enzyme, alternariol-O-methyltransferase (AOH-MT), appeared in control mycelia during the early stationary growth phase. No AOH-MT activity appeared in mycelia blocked in polyketide synthesis by addition of NaNO3. Later addition of NaNO3 reduced the AOH-MT specific activity to 50% of that of the control, whereas the total of activity per mycelium was the same. The AOH-MT activity in vitro was not affected by 100 mM NaNO3. The results suggest that nitrogen in some way inhibited the formation of active enzymes in the polyketide-synthesizing pathway in A. alternata when it was added before these enzymes were formed. PMID:2904801

Orvehed, M; Haggblom, P; Soderhall, K

1988-01-01

77

Stem Cells  

MedlinePLUS

Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair ... body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

78

Detached leaf inoculation of germplasm for rapid screening of resistance to citrus canker and citrus bacterial spot  

Microsoft Academic Search

A detached leaf protocol for rapid screening of germplasm for resistance to citrus canker (Xanthomonas citri subsp. citri, Xcc) and citrus bacterial spot (Xanthomonas alfalfae subsp. citrumelonis, Xac) was developed to evaluate limited quantities of leaf material. Bacterial inocula of Xcc or Xac at 104, 105, or 108 cfu ml?1 were injection-infiltrated into the abaxial surface of disinfested, immature leaves of susceptible

Marta I. Francis; Alma Peña; James H. Graham

2010-01-01

79

Modelling the progress of Asiatic citrus canker on Tahiti lime in relation to temperature and leaf wetness  

Microsoft Academic Search

The combined effect of temperature (15°C, 20°C, 25°C, 30°C, 35°C, 40°C and 42°C) and leaf wetness duration (0, 4, 8 12, 16,\\u000a 20 and 24 h) on infection and development of Asiatic citrus canker (Xanthomonas citri subsp. citri) on Tahiti lime plant was examined in growth chambers. No disease developed at 42°C and zero hours of leaf wetness. Periods\\u000a of leaf

R. S. C. Christiano; M. Dalla Pria; W. C. Jesus Junior; L. Amorim; A. Bergamin Filho

2009-01-01

80

Pseudomonas syringae pv. avii (pv. nov.), the Causal Agent of Bacterial Canker of Wild Cherries ( Prunus avium ) in France  

Microsoft Academic Search

Bacterial strains isolated from cankers of wild cherry trees (Prunus avium) in France were characterized using numerical taxonomy of biochemical tests, DNA–DNA hybridization, repeat sequence primed-PCR (rep-PCR) based on REP, ERIC and BOX sequences, heteroduplex mobility assay (HMA) of internal transcribed spacer (ITS) as well as pathogenicity on wild cherry trees and other species of Prunus. They were compared to

M. Ménard; L. Sutra; J. Luisetti; J. P. Prunier; L. Gardan

2003-01-01

81

Genetic variability of Brazilian isolates of Alternaria alternata detected by AFLP and RAPD techniques  

PubMed Central

The Alternaria brown spot (ABS) is a disease caused in tangerine plants and its hybrids by the fungus Alternaria alternata f. sp. citri which has been found in Brazil since 2001. Due to the recent occurrence in Brazilian orchards, the epidemiology and genetic variability of this pathogen is still an issue to be addressed. Here it is presented a survey about the genetic variability of this fungus by the characterization of twenty four pathogenic isolates of A. alternata f. sp. citri from citrus plants and four endophytic isolates from mango (one Alternaria tenuissima and three Alternaria arborescens). The application of two molecular markers Random Amplified Polymorphic DNA (RAPD) and Amplified Fragment Length Polymorphism (AFLP) had revealed the isolates clustering in distinct groups when fingerprintings were analyzed by Principal Components Analysis (PCA). Despite the better assessment of the genetic variability through the AFLP, significant modifications in clusters components were not observed, and only slight shifts in the positioning of isolates LRS 39/3 and 25M were observed in PCA plots. Furthermore, in both analyses, only the isolates from lemon plants revealed to be clustered, differently from the absence of clustering for other hosts or plant tissues. Summarizing, both RAPD and AFLP analyses were both efficient to detect the genetic variability within the population of the pathogenic fungus Alternaria spp., supplying information on the genetic variability of this species as a basis for further studies aiming the disease control. PMID:24031413

Dini-Andreote, Francisco; Pietrobon, Vivian Cristina; Andreote, Fernando Dini; Romao, Aline Silva; Sposito, Marcel Bellato; Araujo, Welington Luiz

2009-01-01

82

Role of weather on Alternaria Leaf Blight Disease and its effect on Yield and Yield Components of Mustard  

Microsoft Academic Search

Alternaria leaf blight disease caused by Alternaria brassicae in mustard (Brassica juncea (L) Czern and Coss) was studied in two crop seasons, 1992 and 1993 in Nepal at Nawalpur, Sarlahi (Tarai) and Khumaltar, Lalitpur (mid hill). At Nawalpur, epidemics of the disease was recorded for both seasons. Weather conditions like humidity, temperature and frequent rainfall played key role for the

Sundar K Shrestha; Lisa Munk; Suresh B Mathur

2010-01-01

83

Cutaneous Infection with Alternaria triticina in a Bilateral Lung Transplant Recipient.  

PubMed

We report the case of a 60-year-old man who was receiving immunosuppressive therapy for a bilateral lung transplant and presented with a crusted, violaceous plaque on the left hand. Based on histopathology and microbiological culture the patient was diagnosed with infection by Alternaria species. Treatment with itraconazole led to complete resolution of the skin lesion. Forty months later he developed four reddish, nodular, skin lesions on the left leg. Analysis of a biopsy from one of these lesions using histopathologic and molecular techniques identified a mold that shared 98% homology with a strain of Alternaria triticina. Alternaria species belong to a group of dematiaceous fungi that cause opportunistic infections in humans. The incidence of these infections is increasing, mainly in transplant centers. To the best of our knowledge, this is the first reported case of a human infection caused by A. triticina. PMID:24440281

González-Vela, M C; Armesto, S; Unda-Villafuerte, F; Val-Bernal, J F

2014-10-01

84

Alt a 1 from Alternaria interacts with PR5 thaumatin-like proteins.  

PubMed

Alt a 1 is a protein found in Alternaria alternata spores related to virulence and pathogenicity and considered to be responsible for chronic asthma in children. We found that spores of Alternaria inoculated on the outer surface of kiwifruits did not develop hyphae. Nevertheless, the expression of Alt a 1 gene was upregulated, and the protein was detected in the pulp where it co-localized with kiwi PR5. Pull-down assays demonstrated experimentally that the two proteins interact in such a way that Alt a 1 inhibits the enzymatic activity of PR5. These results are relevant not only for plant defense, but also for human health as patients with chronic asthma could suffer from an allergic reaction when they eat fruit contaminated with Alternaria. PMID:24642375

Gómez-Casado, Cristina; Murua-García, Amaya; Garrido-Arandia, María; González-Melendi, Pablo; Sánchez-Monge, Rosa; Barber, Domingo; Pacios, Luis F; Díaz-Perales, Araceli

2014-05-01

85

Using real-time PCR to survey frequency of azoxystrobin-resistant allele G143A in Alternaria populations from almond and pistachio orchards in California  

Microsoft Academic Search

Alternaria spp. cause leaf spot of almond and Alternaria late blight of pistachio in California, and azoxystrobin is a strobilurin fungicide that has been registered for the control of these diseases. To date, only a single point mutation of G143A in cytochrome b resulting to azoxystrobin resistance in Alternaria spp. was found in California. Based on this single point mutation,

Yong Luo; Zhonghua Ma; Heraclio C. Reyes; Dave P. Morgan; Themis J. Michailides

2007-01-01

86

Summer heat and low soil organic matter influence severity of hazelnut Cytospora canker.  

PubMed

Cytospora canker, caused by the fungus Cytospora corylicola, is present in hazelnut production areas worldwide. The disease is widespread throughout the main production areas of Italy. The causal agent is considered to be a secondary invader of damaged tissue that attacks mainly stressed plants. However, little is known of disease severity and stress factors that predispose plants to infection. In particular, the role of pedoclimatic factors was investigated. Direct survey indicated that disease severity varied across several study sites. Geostatistics showed a strong positive correlation between disease severity index and summer heat (r = 0.80 and 0.91 for July and August, respectively) and strong negative correlation between disease severity index and soil organic matter (r = -0.78). A moderate positive correlation between disease severity index and magnesium/potassium ratio (r = 0.58) and moderate negative correlations between disease severity index and total soil nitrogen (r = -0.53), thermal shock (r = -0.46), and rainfall (r = -0.53) were determined. No significant correlation between disease severity index and soil aluminum (r = -0.35), soil pH (r = -0.01), and plant age (r = -0.38) was found. PMID:24168042

Lamichhane, Jay Ram; Fabi, Alfredo; Varvaro, Leonardo

2014-04-01

87

Acinetobacter qingfengensis sp. nov., isolated from canker bark of Populus x euramericana.  

PubMed

Two Gram-negative, non-motile, rod-shaped bacterial strains, 2BJ1(T) and 2C-3-1, were isolated from canker bark of Populus × euramericana collected from different locations in Puyang City, Henan Province, China. The two strains were characterized using nutritional and physiological testing and DNA sequence analysis. They were found to produce acid from d-glucose. Haemolysis was not observed on agar medium supplemented with sheep erythrocytes. Phylogenetic analysis based on 16S rRNA, rpoB and gyrB gene sequences revealed that the strains formed a distinct cluster with 100?% bootstrap support within the genus Acinetobacter in all phylogenetic trees. The phenotypic characteristics most useful for the differentiation of the two strains from other species of the genus Acinetobacter were their ability to grow at 41 °C and to assimilate malonate, phenylacetate and trigonelline. Based on phenotypic, genotypic and phylogenetic characteristics, the two strains are considered to represent a novel species of the genus Acinetobacter, for which the name Acinetobacter qingfengensis sp. nov. is proposed. The type strain is 2BJ1(T) (?=?CFCC 10890(T)?=?KCTC 32225(T)). PMID:24363297

Li, Yong; He, Wei; Wang, Tao; Piao, Chun-gen; Guo, Li-min; Chang, Ju-pu; Guo, Min-Wei; Xie, Shou-jiang

2014-03-01

88

Novel hosts of the Eucalyptus canker pathogen Chrysoporthe cubensis and a new Chrysoporthe species from Colombia.  

PubMed

The pathogen Chrysoporthe cubensis (formerly Cryphonectria cubensis) is best known for the important canker disease that it causes on Eucalyptus species. This fungus is also a pathogen of Syzygium aromaticum (clove), which is native to Indonesia, and like Eucalyptus, is a member of Myrtaceae. Furthermore, C. cubensis has been found on Miconia spp. native to South America and residing in Melastomataceae. Recent surveys have yielded C. cubensis isolates from new hosts, characterized in this study based on DNA sequences for the ITS and beta-tubulin gene regions. These hosts include native Clidemia sericea and Rhynchanthera mexicana (Melastomataceae) in Mexico, and non-native Lagerstroemia indica (Pride of India, Lythraceae) in Cuba. Isolates from these hosts and areas group in the sub-clade of C. cubensis accommodating the South American collections of the fungus. This sub-clade also includes isolates recently collected from Eucalyptus in Cuba, which are used to epitypify C. cubensis. New host records from Southeast Asia include exotic Tibouchina urvilleana from Singapore and Thailand and native Melastoma malabathricum (Melastomataceae) in Sumatra, Indonesia. Consistent with their areas of occurrence isolates from the latter collections group in the Asian sub-clade of C. cubensis. DNA sequence comparisons of isolates from Tibouchina lepidota in Colombia revealed that they represent a new sub-clade within the greater Chrysoporthe clade. Isolates in this clade are described as Chrysoporthe inopina sp. nov., based on distinctive morphological differences. PMID:16876702

Gryzenhout, Marieka; Rodas, Carlos A; Portales, Julio Mena; Clegg, Paul; Wingfield, Brenda D; Wingfield, Michael J

2006-07-01

89

Tall fescue is a potential spillover reservoir host for Alternaria species.  

PubMed

The spread of invasive species is complicated and multifaceted. Enemy spillover (i.e. the transfer of a natural enemy from a reservoir host to a novel host) is one mechanism that facilitates the spread of non-native species. The reservoir host is a species that harbors high abundance of the enemy with little cost to fitness. We asked whether Schedonorus arundinaceus (tall fescue), a highly invasive grass species in North America, is a potential reservoir host for the ubiquitous genus of fungi, Alternaria. We also asked whether spillover of Alternaria is possible among grasses that commonly occur with S. arundinaceus in grassland ecosystems. We performed a greenhouse cross inoculation of three isolates of Alternaria and six grass species (three native, three invasive, including S. arundinaceus). We determined that spillover is possible because the fungal isolates infected and caused disease symptoms on all six grasses and decreased biomass in two of the grass species. We also determined that the invasive grass species appear to be more competent hosts than the native species and that S. arundinaceus could be a likely reservoir host for Alternaria spp. because it can harbor the pathogen with no apparent fitness cost. PMID:24603832

Wilson, Hannah E; Carroll, George C; Roy, Bitty A; Blaisdell, G Kai

2014-01-01

90

Inhibition of polyketide synthesis in Alternaria alternata by the fatty acid synthesis inhibitor cerulenin.  

PubMed Central

The fatty acid synthase inhibitor cerulenin (50 to 100 micrograms/ml) inhibited production of the polyketide mycotoxins alternariol (AOH) and alternariol monomethyl ether (AME) by the mold Alternaria alternata. The results suggested that AOH synthesis was inhibited by a direct mechanism by cerulenin, whereas production of AME was probably limited by a shortage of the precursor AOH. PMID:1575478

Hiltunen, M; Soderhall, K

1992-01-01

91

Release of alkenyl isothiocyanates and other volatiles from Brassica rapa seedlings during infection by Alternaria brassicae  

Microsoft Academic Search

When Brassica rapa seedlings were inoculated with the fungal pathogen Alternaria brassicae, 3-butenyl and 4-pentenyl isothiocyanates were released, together with dimethyl disulphide, dimethyl trisulphide, 4-oxoisophorone and a number of sesquiterpenes. Release of isothiocyanates is evidence for the catabolism of glucosinolates during infection, which is a prerequisite for their involvement in resistance.

Kevin J. Doughty; Margaret M. Blight; Clive H. Bock; Jane K. Fieldsend; John A. Pickett

1996-01-01

92

Effects of the nematicide 1,3-dichloropropene on weed populations and stem canker disease severity in potatoes  

Microsoft Academic Search

The soil fumigant 1,3-dichloropropene (1,3-D) has been used in the UK for the control of potato cyst nematodes (PCN), Globodera pallida (Stone) and Globodera rostochiensis (Wollenweber), but its potential herbicidal activity has not been extensively investigated in this country. Field and glasshouse studies were therefore conducted to evaluate the potential of 1,3-D for the control of weeds in potatoes, and

Patrick P. J. Haydock; Thomas Deliopoulos; Ken Evans; Stephen T. Minnis

2010-01-01

93

Alternaria induces STAT-6 dependent acute airway eosinophila and epithelial FIZZ1 expression that promotes airway fibrosis and epithelial thickness  

PubMed Central

The fungal allergen, Alternaria, is specifically associated with severe asthma, including life-threatening exacerbations. To better understand the acute innate airway response to Alternaria, naïve WT mice were challenged once intranasally with Alternaria. Naïve WT mice developed significant BAL eosinophila following Alternaria challenge when analyzed 24 hours later. In contrast to Alternaria, neither Aspergillus nor Candida induced BAL eosinophilia. Gene microarray analysis of airway epithelial cell brushings demonstrated that Alternaria-challenged naïve WT mice had an over 20 fold increase level of expression of “Found in Inflammatory Zone 1” (FIZZ1/Retnla), a resistin-like molecule. Lung immunostaining confirmed strong airway epithelial FIZZ1 expression present as early as 3 hours after a single Alternaria challenge that persisted for at least 5 days and was significantly reduced in STAT6-deficient, but not PAR-2-deficient mice. Bone marrow chimera studies revealed that STAT6 expressed in lung cells was required for epithelial FIZZ1 expression, while in contrast, STAT6 present in bone marrow derived cells contributed to airway eosinophilia. Studies investigating which cells in the non-challenged lung bind FIZZ1 demonstrated that CD45+CD11c+ (macrophages and dendritic cells) as well as collagen-1 producing CD45 negative cells (fibroblasts) can bind to FIZZ1. Importantly, direct administration of recombinant FIZZ1 to naïve WT mice led to airway eosinophilia, peribronchial fibrosis, and increased thickness of the airway epithelium. Thus, Alternaria induces STAT-6 dependent acute airway eosinophila and epithelial FIZZ1 expression that promotes airway fibrosis and epithelial thickness. This may provide some insight into the uniquely pathogenic aspects of Alternaria-associated asthma. PMID:22327070

Doherty, Taylor A.; Khorram, Naseem; Sugimoto, Kotaro; Sheppard, Dean; Rosenthal, Peter; Youn Cho, Jae; Pham, Alexa; Miller, Marina; Croft, Michael; Broide, David H.

2012-01-01

94

Artificial neural network models of relationships between Alternaria spores and meteorological factors in Szczecin (Poland)  

NASA Astrophysics Data System (ADS)

Alternaria is an airborne fungal spore type known to trigger respiratory allergy symptoms in sensitive patients. Aiming to reduce the risk for allergic individuals, we constructed predictive models for the fungal spore circulation in Szczecin, Poland. Monthly forecasting models were developed for the airborne spore concentrations of Alternaria, which is one of the most abundant fungal taxa in the area. Aerobiological sampling was conducted over 2004-2007, using a Lanzoni trap. Simultaneously, the following meteorological parameters were recorded: daily level of precipitation; maximum and average wind speed; relative humidity; and maximum, minimum, average, and dew point temperature. The original factors as well as with lags (up to 3 days) were used as the explaining variables. Due to non-linearity and non-normality of the data set, the modelling technique applied was the artificial neural network (ANN) method. The final model was a split model with classification (spore presence or absence) followed by regression for spore seasons and log(x+1) transformed Alternaria spore concentration. All variables except maximum wind speed and precipitation were important factors in the overall classification model. In the regression model for spore seasons, close relationships were noted between Alternaria spore concentration and average and maximum temperature (on the same day and 3 days previously), humidity (with lag 1) and maximum wind speed 2 days previously. The most important variable was humidity recorded on the same day. Our study illustrates a novel approach to modelling of time series with short spore seasons, and indicates that the ANN method provides the possibility of forecasting Alternaria spore concentration with high accuracy.

Grinn-Gofro?, Agnieszka; Strzelczak, Agnieszka

2008-11-01

95

DNA Polymorphisms and Biocontrol of Bacillus Antagonistic to Citrus Bacterial Canker with Indication of the Interference of Phyllosphere Biofilms  

PubMed Central

Citrus bacterial canker caused by Xanthomonas axonopodis pv. citri is a devastating disease resulting in significant crop losses in various citrus cultivars worldwide. A biocontrol agent has not been recommended for this disease. To explore the potential of bacilli native to Taiwan to control this disease, Bacillus species with a broad spectrum of antagonistic activity against various phytopathogens were isolated from plant potting mixes, organic compost and the rhizosphere soil. Seven strains TKS1-1, OF3-16, SP4-17, HSP1, WG6-14, TLB7-7, and WP8-12 showing superior antagonistic activity were chosen for biopesticide development. The genetic identity based on 16S rDNA sequences indicated that all seven native strains were close relatives of the B. subtilis group and appeared to be discrete from the B. cereus group. DNA polymorphisms in strains WG6-14, SP4-17, TKS1-1, and WP8-12, as revealed by repetitive sequence-based PCR with the BOXA1R primers were similar to each other, but different from those of the respective Bacillus type strains. However, molecular typing of the strains using either tDNA-intergenic spacer regions or 16S–23S intergenic transcribed spacer regions was unable to differentiate the strains at the species level. Strains TKS1-1 and WG6-14 attenuated symptom development of citrus bacterial canker, which was found to be correlated with a reduction in colonization and biofilm formation by X. axonopodis pv. citri on leaf surfaces. The application of a Bacillus strain TKS1-1 endospore formulation to the leaf surfaces of citrus reduced the incidence of citrus bacterial canker and could prevent development of the disease. PMID:22848728

Huang, Tzu-Pi; Tzeng, Dean Der-Syh; Wong, Amy C. L.; Chen, Chun-Han; Lu, Kuan-Min; Lee, Ya-Huei; Huang, Wen-Di; Hwang, Bing-Fang; Tzeng, Kuo-Ching

2012-01-01

96

Rapid and sensitive detection of Citrus Bacterial Canker by loop-mediated isothermal amplification combined with simple visual evaluation methods  

PubMed Central

Background Citrus Bacterial Canker (CBC) is a major, highly contagious disease of citrus plants present in many countries in Asia, Africa and America, but not in the Mediterranean area. There are three types of Citrus Bacterial Canker, named A, B, and C that have different genotypes and posses variation in host range within citrus species. The causative agent for type A CBC is Xanthomonas citri subsp. citri, while Xanthomonas fuscans subsp. aurantifolii, strain B causes type B CBC and Xanthomonas fuscans subsp. aurantifolii strain C causes CBC type C. The early and accurate identification of those bacteria is essential for the protection of the citrus industry. Detection methods based on bacterial isolation, antibodies or polymerase chain reaction (PCR) have been developed previously; however, these approaches may be time consuming, laborious and, in the case of PCR, it requires expensive laboratory equipment. Loop-mediated isothermal amplification (LAMP), which is a novel isothermal DNA amplification technique, is sensitive, specific, fast and requires no specialized laboratory equipment. Results A loop-mediated isothermal amplification assay for the diagnosis of Citrus Bacterial Canker (CBC-LAMP) was developed and evaluated. DNA samples were obtained from infected plants or cultured bacteria. A typical ladder-like pattern on gel electrophoresis was observed in all positive samples in contrast to the negative controls. In addition, amplification products were detected by visual inspection using SYBRGreen and using a lateral flow dipstick, eliminating the need for gel electrophoresis. The sensitivity and specificity of the assay were evaluated in different conditions and using several sample sources which included purified DNA, bacterium culture and infected plant tissue. The sensitivity of the CBC-LAMP was 10 fg of pure Xcc DNA, 5 CFU in culture samples and 18 CFU in samples of infected plant tissue. No cross reaction was observed with DNA of other phytopathogenic bacteria. The assay was capable of detecting CBC-causing strains from several geographical origins and pathotypes. Conclusions The CBC-LAMP technique is a simple, fast, sensitive and specific method for the diagnosis of Citrus Bacterial Canker. This method can be useful in the phytosanitary programs of the citrus industry worldwide. PMID:20565886

2010-01-01

97

Lateral organ boundaries 1 is a disease susceptibility gene for citrus bacterial canker disease.  

PubMed

Citrus bacterial canker (CBC) disease occurs worldwide and incurs considerable costs both from control measures and yield losses. Bacteria that cause CBC require one of six known type III transcription activator-like (TAL) effector genes for the characteristic pustule formation at the site of infection. Here, we show that Xanthomonas citri subspecies citri strain Xcc306, with the type III TAL effector gene pthA4 or with the distinct yet biologically equivalent gene pthAw from strain XccA(w), induces two host genes, CsLOB1 and CsSWEET1, in a TAL effector-dependent manner. CsLOB1 is a member of the Lateral Organ Boundaries (LOB) gene family of transcription factors, and CsSWEET1 is a homolog of the SWEET sugar transporter and rice disease susceptibility gene. Both TAL effectors drive expression of CsLOB1 and CsSWEET1 promoter reporter gene fusions when coexpressed in citrus or Nicotiana benthamiana. Artificially designed TAL effectors directed to sequences in the CsLOB1 promoter region, but not the CsSWEET1 promoter, promoted pustule formation and higher bacterial leaf populations. Three additional distinct TAL effector genes, pthA*, pthB, and pthC, also direct pustule formation and expression of CsLOB1. Unlike pthA4 and pthAw, pthB and pthC do not promote the expression of CsSWEET1. CsLOB1 expression was associated with the expression of genes associated with cell expansion. The results indicate that CBC-inciting species of Xanthomonas exploit a single host disease susceptibility gene by altering the expression of an otherwise developmentally regulated gene using any one of a diverse set of TAL effector genes in the pathogen populations. PMID:24474801

Hu, Yang; Zhang, Junli; Jia, Hongge; Sosso, Davide; Li, Ting; Frommer, Wolf B; Yang, Bing; White, Frank F; Wang, Nian; Jones, Jeffrey B

2014-01-28

98

Association of IL-4RA single nucleotide polymorphisms, HLA-DR and HLA-DQ in children with Alternaria-sensitive moderate-severe asthma  

PubMed Central

Background Asthma afflicts 6% to 8% of the United States population, and severe asthma represents approximately 10% of asthmatic patients. Several epidemiologic studies in the United States and Europe have linked Alternaria sensitivity to both persistence and severity of asthma. In order to begin to understand genetic risk factors underlying Alternaria sensitivity and asthma, in these studies we examined T cell responses to Alternaria antigens, HLA Class II restriction and HLA-DQ protection in children with severe asthma. Methods Sixty children with Alternaria-sensitive moderate-severe asthma were compared to 49 children with Alternaria-sensitive mild asthma. We examined HLA-DR and HLA-DQ frequencies in Alternaria-sensitive asthmatic by HLA typing. To determine ratios of Th1/Th2 Alternaria-specific T-cells, cultures were stimulated in media alone, Alternaria alternata extract and Alt a1. Sensitivity to IL-4 stimulation was measured by up-regulation of CD23 on B cells. Results Children with Alternaria-sensitive moderate-severe asthma trended to have increased sensitivities to Cladosporium (46% versus 35%), to Aspergillus (43% versus 28%), and significantly increased sensitivities to trees (78% versus 57%) and to weeds (68% versus 48%). The IL-4RA ile75val polymorphism was significantly increased in Alternaria-sensitive moderate-severe asthmatics, 83% (0.627 allele frequency) compared to Alternaria-sensitive mild asthmatics, 57% (0.388 allele frequency). This was associated with increased sensitivity to IL-4 stimulation measured by significantly increased IL-4 stimulated CD23 expression on CD19+ and CD86+CD19+ B cells of Alternaria-sensitive moderate-severe asthmatics. IL-5 and IL-13 synthesis was significantly increased in Alternaria-sensitive moderate-severe asthmatics compared to mild asthmatics to Alternaria extract and Alt a1 stimulation. The frequency of HLA-DQB1*03 allele was significantly decreased in Alternaria-sensitive moderate-severe asthmatics compared to mild asthmatics, 39% versus 63%, with significantly decreased allele frequency, 0.220 versus 0.398. Summary In children with Alternaria-sensitive moderate severe asthma, there was an increased Th2 response to Alternaria stimulation and increased sensitivity to IL-4 stimulation. This skewing towards a Th2 response was associated with an increased frequency of the IL-4RA ile75val polymorphism. In evaluating the HLA association, there was a decreased frequency of HLA-DQB1*03 in Alternaria-sensitive moderate severe asthmatic children consistent with previous studies suggest that HLA-DQB1*03 may be protective against the development of mold-sensitive severe asthma. PMID:20298583

2010-01-01

99

Evaluation of non-chemical seed treatment methods for the control of Alternaria dauci and A. radicina on carrot seeds  

Microsoft Academic Search

The current study was initiated to evaluate the efficacy of physical methods (hot water, aerated steam, electron treatment)\\u000a and agents of natural origin (resistance inducers, plant derived products, micro-organisms) as seed treatments of carrots\\u000a for control of Alternaria dauci and A. radicina. Control of both Alternaria species by seed treatment with the resistance inducers was generally poor. Results were also

Eckhard Koch; Annegret Schmitt; Dietrich Stephan; Carola Kromphardt; Marga Jahn; Hermann-Josef Krauthausen; Gustaf Forsberg; Sigrid Werner; Tahsein Amein; Sandra A. I. Wright; Federico Tinivella; Maria L. Gullino; Steven J. Roberts; Jan van der Wolf; Steven P. C. Groot

2010-01-01

100

PHENOTYPIC AND MOLECULAR PROPERTIES OF PSEUDOMONAS SYRINGAE pv. SYRINGAE THE CAUSAL AGENT OF BACTERIAL CANKER OF STONE FRUIT TREES IN KURDISTAN PROVINCE  

Microsoft Academic Search

SUMMARY Since 2005, a disease similar to bacterial canker of stone fruit trees was observed in some areas of Kurdis- tan province, Iran. A total of 12 bacterial isolates were obtained from infected tissues of apricot and peach trees. According to biochemical, physiological and whole cell protein patterns, isolates were identified as Pseudomonas syringae pv. syringae. Some molecular properties of

G. Karimi-Kurdistani; B. Harighi

2008-01-01

101

Fusicoccum arbuti sp. nov. causing cankers on pacific madrone in western North America with notes on Fusicoccum dimidiatum, the correct name for Scytalidium dimidiatum and Nattrassia mangiferae.  

PubMed

Pacific madrone (Arbutus menziesii) is a broadleaf evergreen tree native to western North America that has been in decline for the past 30 years. A fungus has been isolated and was verified as the cause of cankers on dying trees. It was determined to belong in the genus Fusicoccum, an asexual state of Botryosphaeria. This genus in both its sexual and asexual states commonly causes canker diseases of deciduous woody plants. Using morphological and molecular data the fungus causing cankers on Pacific madrone is characterized, described and illustrated as a new species of Fusicoccum, F. arbuti D.F. Farr & M. Elliott sp. nov. No sexual state is known for F. arbuti. Evidence from the literature, cultures and specimens suggests that F. arbuti, often mistakenly identified as Nattrassia mangiferae, has been causing madrone canker since at least 1968. Authentic isolates of Nattrassia mangiferae as the synanamorph Scytalidium dimidiatum were sequenced and determined to be different from Fusicoccum arbuti and to belong in Botryosphaeria/Fusicoccum. In addition to molecular sequence data, the morphology of the pycnidial and arthric conidial states of Nattrassia mangiferae/ Scytalidium dimidiatum resembles that of Fusicoccum. Therefore the correct name for Nattrassia mangiferae and its numerous synonyms (Dothiorella mangiferae, Torula dimidata, Scytilidium dimidiatum, Fusicoccum eucalypti, Hendersonula toruloidea, H. cypria, Exosporina fawcetii, H. agathidia, and S. lignicola) is Fusicoccum dimidiatum (Penz.) D.F. Farr, comb. nov. PMID:16392261

Farr, David F; Elliott, Marianne; Rossman, Amy Y; Edmonds, Robert L

2005-01-01

102

Alternaria toxins: DNA strand-breaking activity in mammalian cells in vitro  

Microsoft Academic Search

Treatment, for 1 h, of cultured Chinese hamster V79 cells, human liver HepG2 cells, and human colon HT-29 cells with theAlternaria toxins alternariol (AOH) and alternariol methyl ether (AME) caused a concentration-dependent induction of DNA strand breaks\\u000a at concentrations ranging from 5 to 50 micromolar. After treatment for 24 h, DNA strand breaks were observed in HepG2 but\\u000a not HT-29

E. Pfeiffer; S. Eschbach; M. Metzler

2007-01-01

103

Relationship between Fusarium graminearum and Alternaria alternata contamination and deoxynivalenol occurrence on Argentinian durum wheat  

Microsoft Academic Search

A mycological survey was carried out on durum wheat (Triticum durum) samples from the main production area of Argentina. The\\u000a isolation frequency and relative density of species of dematiaceous fungi, and genus Fusarium were calculated. Alternaria\\u000a alternata and Fusarium graminearum were the predominant fungal species. An analysis of deoxynivalenol (DON) natural contamination\\u000a was also performed on a limited number of

H. H. L. González; E. J. Mart; A. Pacin; S. L. Resnik; Cient ´ ificas

1998-01-01

104

Solubilization of Acid-Swollen Cellulose by an Enzyme System from a Species of Alternaria1  

PubMed Central

An unknown species of Alternaria, when grown on a medium containing carboxymethylcellulose as a carbon source produced a mixture of extracellular enzymes which solubilized acid-swollen cellulose. The product of the hydrolysis was a 1:2 molar mixture of cellobiose and glucose. The organism apparently produced no cellobiase. It is suggested that the mixture of cellulolytic enzymes contains at least two different enzymes which degrade cellulose in an endwise manner. PMID:16349671

Logan, Robert M.; Siehr, Donald J.

1966-01-01

105

Preparative Isolation and Purification of Altertoxin I from an Alternaria sp. by HSCCC  

Microsoft Academic Search

Altertoxin I (ATX I) is one of the common mycotoxins produced by genus Alternaria which is a common food pathogen of fruits and grains. To prepare enough quantity of pure ATX I for further research of mutagenicity\\u000a and toxicology tests, a novel method using preparative high-speed counter-current chromatography (HSCCC) was developed. The\\u000a ethyl acetate crude extracts of the acetone washes

Dejun Hu; Miao Liu; Xing Xia; Daijie Chen; Fengsheng Zhao; Mei Ge

2008-01-01

106

Microbial transformation of deoxyandrographolide by Alternaria alternata AS 3.4578.  

PubMed

Biotransformation of deoxyandrographolide (1) by Alternaria alternata AS 3.4578 gave five derivatives identified by spectral methods including 2D NMR as the known dehydroandrographolide (2) and 9beta-hydroxy-dehydroandrographolide (3) and the new compounds 9beta-hydroxy-deoxyandrographolide (4), 3alpha,17,19-trihydroxy-8,13-ent-labdadien-15,16-olide (5) and 3-oxo-9beta-hydroxy-deoxyandrographolide (6). PMID:21815410

Xin, Xiu-Lan; Deng, Sha; Zhang, Bao-Jing; Huang, Shan-Shan; Tian, Yan; Ma, Xiao-Chi; An, Lei; Shu, Xiao-Hong; Yao, Ji-Hong; Cui, Xun

2011-06-01

107

Interaction between Alternaria alternata or Fusarium equiseti and Glomus mosseae and its effects on plant growth  

Microsoft Academic Search

The effect of inoculation with the saprophytic fungi Alternaria alternata or Fusarium equiseti on maize (Zea mays) and lettuce (Lactuca sativa) with or without arbuscular mycorrhizal (AM) colonization by Glomus mosseae was studied in a greenhouse trial. Plant dry weights of non-AM-inoculated maize and lettuce were unaffected by the presence\\u000a of A. alternata and F. equiseti. In contrast, A. alternata

C. B. McAllister; J. M. Garcia-Garrido; I. Garcia-Romera; A. Godeas; J. A. Ocampo

1997-01-01

108

Agrobacterium tumefaciens-mediated transformation of the causative agent of Valsa canker of apple tree Valsa mali var. mali.  

PubMed

Valsa mali var. mali (Vmm), which is the causative agent of Valsa canker of apple tree, causes heavy damage to apple production in eastern Asia. In this article, we report Agrobacterium tumefaciens-mediated transformation (ATMT) of Vmm and expression of gfp (green fluorescent protein) in this fungus. The transformation system was optimized to a transformation efficiency of approximately 150 transformants/10(6) conidia, and a library containing over 4,000 transformants was generated. The tested transformants were mitotically stable. One hundred percent hph (hygromycin B phosphotransferase) integration into Vmm was identified by PCR and five single-copy integration of T-DNA was detected in the eighteen transformants by Southern blot. To our knowledge, this is the first report of ATMT of Vmm. Furthermore, this library has been used to identify genes involved in the virulence of the pathogen, and the transformation system may also be useful to the transformation of other species of the genus Valsa. PMID:24554343

Hu, Yang; Dai, Qingqing; Liu, Yangyang; Yang, Zhe; Song, Na; Gao, Xiaoning; Voegele, Ralf Thomas; Kang, Zhensheng; Huang, Lili

2014-06-01

109

Characterization and pathogenicity of Alternaria spp. strains associated with grape bunch rot during post-harvest withering.  

PubMed

Alternaria is a fungal agent of grape bunch rot which occurs during withering, a process which produces passito style wines. Seven isolates of Alternaria spp. were characterized using morphological examination, genotypic analysis and pathogenicity. Six of these isolates produced conidiophores and conidia displaying sporulation patterns typical of the Alternaria alternata species-group. Variability in colony morphology and growth on different media was observed. Phylogenetic analysis of internal transcribed spacer (ITS) sequences clustered all isolates within a monophyletic clade, while intergenic spacer region (IGS)-RFLP profiles were congruent with those of A. alternata and Alternaria arborescens. RAPD-PCR proved helpful in discriminating between strains. To assay strain pathogenicity, grape berries were infected while undergoing withering conditions at different temperatures. Disease capacity was found to be strain dependent and varied consistently between the most and least aggressive strains. This study has provided interesting information on polymorphism within Alternaria spp. populations in withered grapes and on understanding the saprophytic role of this fungus during the post-harvest dehydrating process. PMID:24974273

Lorenzini, Marilinda; Zapparoli, Giacomo

2014-09-01

110

Hourly predictive artificial neural network and multivariate regression tree models of Alternaria and Cladosporium spore concentrations in Szczecin (Poland).  

PubMed

A study was made of the link between time of day, weather variables and the hourly content of certain fungal spores in the atmosphere of the city of Szczecin, Poland, in 2004-2007. Sampling was carried out with a Lanzoni 7-day-recording spore trap. The spores analysed belonged to the taxa Alternaria and Cladosporium. These spores were selected both for their allergenic capacity and for their high level presence in the atmosphere, particularly during summer. Spearman correlation coefficients between spore concentrations, meteorological parameters and time of day showed different indices depending on the taxon being analysed. Relative humidity (RH), air temperature, air pressure and clouds most strongly and significantly influenced the concentration of Alternaria spores. Cladosporium spores correlated less strongly and significantly than Alternaria. Multivariate regression tree analysis revealed that, at air pressures lower than 1,011 hPa the concentration of Alternaria spores was low. Under higher air pressure spore concentrations were higher, particularly when RH was lower than 36.5%. In the case of Cladosporium, under higher air pressure (>1,008 hPa), the spores analysed were more abundant, particularly after 0330 hours. In artificial neural networks, RH, air pressure and air temperature were the most important variables in the model for Alternaria spore concentration. For Cladosporium, clouds, time of day, air pressure, wind speed and dew point temperature were highly significant factors influencing spore concentration. The maximum abundance of Cladosporium spores in air fell between 1200 and 1700 hours. PMID:19526373

Grinn-Gofro?, Agnieszka; Strzelczak, Agnieszka

2009-11-01

111

STEM Career  

NSDL National Science Digital Library

There are many groups and organizations in the United States working to encourage young people to enter STEM-related careers, and this website represents one of those endeavors. The STEM Career website was created by Professor Rich Feller of Colorado State University to help encourage young people to select just such a career path. The website contains updates on STEM career possibilities, and basic answers to questions like "Why STEM?" and "Why STEM Centric Career Development?" Visitors should also scan through the "STEM Disciplines" area on the homepage, as it contains resources about the job outlook for related STEM disciplines, such as biochemical engineering and engineering managers. Moving on, the site also features news updates from Professor Feller and his colleagues on subjects that include the ways in which corporations are promoting STEM education and women in STEM.

112

Perylene derivatives produced by Alternaria alternata, an endophytic fungus isolated from Laurencia species.  

PubMed

Two new perylene derivatives, 7-epi-8-hydroxyaltertoxin I (1) and 6-epi-stemphytriol (2), along with two known compounds stemphyperylenol (3) and altertoxin I (4) were isolated from Alternaria alternata, a marine endophytic fungus derived from an unidentified algal species of the genus Laurencia. Structures of compounds 1-4 were determined on the basis of detailed spectroscopic analysis, as well as by comparison with literature reports. The antimicrobial activities of compounds 1 and 3 against Staphylococcus aureus, Escherichia coli, and Aspergillus niger were evaluated; neither showed obvious activity. PMID:19967977

Gao, Shu-Shan; Li, Xiao-Ming; Wang, Bin-Gui

2009-11-01

113

Light inhibits the production of alternariol and alternariol monomethyl ether in Alternaria alternata.  

PubMed Central

Alternaria alternata (Fr.) Keissler, grown in drop culture, produced alternariol and alternariol monomethyl ether in late growth phase. Production was almost completely inhibited when the fungal cultures were exposed to white light (180 W/m2), although mycelial dry weight was not significantly affected. The fungus was most sensitive to light during the exponential growth phase. Twelve hours of light exposure was sufficient to decrease significantly the production of the secondary metabolites. In light the fungus produced a red-brown pigment of unknown nature. PMID:569466

Soderhall, K; Svensson, E; Unestam, T

1978-01-01

114

Maculosin, a host-specific phytotoxin for spotted knapweed from Alternaria alternata  

PubMed Central

Several diketopiperazines have been isolated from liquid cultures of Alternaria alternata, the causal agent of black leaf blight of spotted knapweed, Centaurea maculosa Lam. One of these compounds, maculosin [the diketopiperazine cyclo(-L-Pro-L-Tyr-)], was active in the nicked-leaf bioassay at 10-5 M; synthetic maculosin possessed chemical and biological activities identical to those of the natural product. Other diketopiperazines isolated from the fungus possessed either less activity or none at all. In tests against 19 plant species, maculosin was phytotoxic only to spotted knapweed. Thus maculosin is a host-specific phytotoxin from a weed pathogen. PMID:16593989

Stierle, Andrea C.; Cardellina, John H.; Strobel, Gary A.

1988-01-01

115

Quantitative Association of Bark Beetles with Pitch Canker Fungus and Effects of Verbenone on Their Semiochemical Communication in Monterey Pine Forests in Northern Spain  

Microsoft Academic Search

The association between 11 species of bark beetles (Coleoptera: Scolytinae) and one weevil (Coleoptera: Entiminae) with the pitch canker fungus, Fusarium circinatum Nirenberg and OÕDonnell, was determined by crushing beetles on selective medium and histone H3 gene sequencing. Pityophthorus pubescens (Marsham) (25.00%), Hylurgops palliatus (Gyllenhal) (11.96%), Ips sexden- tatus (Borner) (8.57%), Hypothenemus eruditus Westwood (7.89%), Hylastes attenuatus Erichson (7.40%), and

Pedro Romón; Juan Carlos Iturrondobeitia; Ken Gibson; B. Staffan Lindgren; Arturo Goldarazena

2007-01-01

116

Invasive Plants, Species and Conditions Fact Sheets: Cheatgrass Brome, Bamboo Reed, Butternut Canker, Dutch Elm, Chestnut Blight, Asian Cycad Scale, Crazy Ant, Red Fox  

NSDL National Science Digital Library

This resource from ATEEC provides a number of fact sheets on invasive plants, species and conditions which may be printed out or used as presentation material. The plants, species and conditions described here are cheatgrass brome, bamboo reed, butternut canker, dutch elm disease, chestnut blight, Asian cycad scale, crazy ant and red fox. The lesson plan is available for download as a PDF; users must create a free, quick login with ATEEC to access the materials.

2013-06-12

117

Genetics of anthracnose panel canker disease resistance and its relationship with yield and growth characters in half-sib progenies of rubber tree (Hevea brasiliensis)  

Microsoft Academic Search

Rubber tree (Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell-Arg) anthracnose panel canker disease resistance, caused by Colletotrichum gloeosporioides (Penz.) Sacc., and growth and yield characters were assessed at three years old in the nursery, in 18 half-sib progenies. There were highly significant (P < 0.01) genetic differences among progenies for most characters. The genetic component of variance accounted for

Paulo de Souza Gonçalves; Edson Luiz Furtado; Ondino Cleante Bataglia; Altino Aldo Ortolani; André May; Giselle Olmos Belletti

1999-01-01

118

STEM Sell  

ERIC Educational Resources Information Center

Between 1994 and 2003, employment in science, technology, engineering and math (STEM) fields grew by a remarkable 23 percent, compared with 17 percent in non-STEM fields, according to federal data. The Bureau of Labor Statistics predicts continued strong growth in STEM job openings through 2014, with emphasis on life sciences, environmental…

Pantic, Zorica

2007-01-01

119

Backbone resonance assignment of Alt a 1, a unique ?-barrel protein and the major allergen of Alternaria alternata.  

PubMed

Alt a 1 is the major allergen of the fungus Alternaria alternata and can be found in the cell wall of its spores. It is a cysteine linked homodimeric protein with a unique ?-barrel fold as recently revealed by X-ray crystallography. Despite the elucidation of its structure, its biological function remains unknown. For Alternaria-sensitized patients, contact leads to respiratory allergy and in severe cases to asthma-related death. Here we report the sequence-specific Alt a 1 backbone (1)H, (15)N and (13)C chemical shift assignment. PMID:23715812

Wagner, Gabriel E; Gutfreund, Sandra; Fauland, Kerstin; Keller, Walter; Valenta, Rudolf; Zangger, Klaus

2014-10-01

120

STEM crisis or STEM surplus?  

E-print Network

The science, technology, engineering, and mathematics (STEM) workforce is a crucial driver of the U.S. economy. Over the last decade, there has been significant concern regarding the adequacy of the supply of STEM workers ...

Xue, Yi, S.M. Massachusetts Institute of Technology

2014-01-01

121

Furfural from Pine Needle Extract Inhibits the Growth of a Plant Pathogenic Fungus, Alternaria mali  

PubMed Central

The antifungal effect of pine needle extract prepared by a distinguishable extraction method and the dry distillation method, was examined. The effect of this extract itself was insignificant. The chemical components of pine needle extract were then investigated by gas chromatographic analysis, and four chemical components, acetol, furfural, 5-methyl furfural, and terpine-4-ol, were identified. The antifungal effects of those four chemical components against Alternaria mali (A. mali), an agent of Alternaria blotch of apple, were then examined. It was observed that the minimum inhibitory concentrations (MICs) were 6.25, 0.78, 0.78, and 12.5 (mg/ml) of acetol, furfural, 5-methyl furfural, and terpine-4-ol, respectively. MICs of furfural and 5-methyl furfural had the same order of magnitude as that of an antifungal agrochemical, chlorothalonil. Although furfural itself can not be completely substituted for an antifungal agrochemical, a partial mixture of furfural and antifungal agrochemical may be used as a substitute. The use of agrochemicals for the prevention of plant disease caused by pathogenic fungus such as A. mali could be partially reduced by the application of this mixture. PMID:24015067

Yoo, Sun Kyun; Moon, Sung-Kwon; Lee, Ung-Soo

2007-01-01

122

A nonribosomal peptide synthetase mediates siderophore production and virulence in the citrus fungal pathogen Alternaria alternata.  

PubMed

Alternaria species produce and excrete dimethyl coprogen siderophores to acquire iron. The Alternaria alternata gene AaNPS6, encoding a polypeptide analogous to fungal nonribosomal peptide synthetases, was found to be required for the production of siderophores and virulence on citrus. Siderophores purified from culture filtrates of the wild-type strain did not induce any phytotoxicity on the leaves of citrus. Fungal strains lacking AaNPS6 produced little or no detectable extracellular siderophores and displayed an increased sensitivity to H?O?, superoxide-generating compounds (KO? and menadione) and iron depletion. ?nps6 mutants were also defective for the production of melanin and conidia. The introduction of a wild-type AaNPS6 under the control of its endogenous promoter to a ?nps6 null mutant at least partially restored siderophore production and virulence to citrus, demonstrating a functional link between iron uptake and fungal pathogenesis. Elevated sensitivity to H?O?, seen for the ?nps6 null strain could be relieved by exogenous application of ferric iron. The expression of the AaNPS6 gene was highly up-regulated under low-iron conditions and apparently controlled by the redox-responsive yeast transcriptional regulator YAP1. Hence, the maintenance of iron homeostasis via siderophore-mediated iron uptake also plays an important role in resistance to toxic reactive oxygen species (ROS). Our results demonstrate further the critical role of ROS detoxification for the pathogenicity of A.?alternata in citrus. PMID:23438010

Chen, Li-Hung; Lin, Ching-Hsuan; Chung, Kuang-Ren

2013-06-01

123

Conservation of the genes for HC-toxin biosynthesis in Alternaria jesenskae  

PubMed Central

Background HC-toxin, a cyclic tetrapeptide, is a virulence determinant for the plant pathogenic fungus Cochliobolus carbonum. It was recently discovered that another fungus, Alternaria jesenskae, also produces HC-toxin. Results The major genes (collectively known as AjTOX2) involved in the biosynthesis of HC-toxin were identified from A. jesenskae by genomic sequencing. The encoded orthologous proteins share 75-85% amino acid identity, and the genes for HC-toxin biosynthesis are duplicated in both fungi. The genomic organization of the genes in the two fungi show a similar but not identical partial clustering arrangement. A set of representative housekeeping proteins show a similar high level of amino acid identity between C. carbonum and A. jesenskae, which is consistent with the close relatedness of these two genera within the family Pleosporaceae (Dothideomycetes). Conclusions This is the first report that the plant virulence factor HC-toxin is made by an organism other than C. carbonum. The genes may have moved by horizontal transfer between the two species, but it cannot be excluded that they were present in a common ancestor and lost from other species of Alternaria and Cochliobolus. PMID:23865912

2013-01-01

124

Stem Cell Basics  

MedlinePLUS

... Center Stem Cell Basics Stem Cell Basics Stem Cell Information Frequently Asked Questions What are stem cells? ... policy? More FAQs Links to related resources Stem Cell Research Center for Regenerative Medicine NIH Stem Cell ...

125

Effects of Leaf Maturity, Infection Site, and Application Rate of Alternaria cirsinoxia Conidia on Infection of Canada Thistle ( Cirsium arvense)  

Microsoft Academic Search

The effects of leaf maturity, infection site, and application rate of Alternaria cirsinoxia conidia on the pre- and postpenetration phases of infection of Canada thistle were studied. Leaf maturity had no effect on the germination of conidia, but appressoria formation was significantly higher on the oldest leaf than on the youngest leaf. There were no differences in the frequency of

S Green; K. L Bailey

2000-01-01

126

Constitutive expression of a celery mannitol dehydrogenase in tobacco enhances resistance to the mannitol-secreting fungal pathogen Alternaria alternata  

Microsoft Academic Search

Summary Our previous observation that host plant extracts induce production and secretion of mannitol in the tobacco pathogen Alternaria alternata suggested that, like their animal counterparts, plant pathogenic fungi might produce the reactive oxygen quencher mannitol as a means of suppressing reactive oxygen- mediated plant defenses. The concurrent discovery that pathogen attack induced mannitol dehydrogenase (MTD) expression in the non-mannitol-containing

Dianne B. Jennings; Margaret E. Daub; D. Mason Pharr; John D. Williamson

2002-01-01

127

Cutaneous infection by Alternaria infectoria in a liver transplant recipient: a case report.  

PubMed

We report the case of a 65-year-old man who developed multiple crusty ulcerative skin lesions on both lower extremities six months after liver transplantation. The causative pathogen was identified as Alternaria Infectoria, an opportunistic fungal agent. The patient was successfully treated with fluconazole for 27 weeks, with complete regression of the lesions. Due to the lack of well-designed clinical studies it is difficult to determine the best treatment course regarding solid organ transplant recipients presenting with invasive fungal infections. And for now, the clinician must lean upon case-reports or retrospective analyses to compose the most suited therapy for his patient. Based upon literature, it seems that the combination of a broad spectrum azole and reducing the dose of immunosuppressive drugs is the cornerstone of treating invasive fungal infections in solid organ transplant patients. PMID:25090825

Coussens, E; Rogge, S; Haspeslagh, M; Geerts, A; Verhelst, X; Van Vlierberghe, H; Troisi, R I; Colle, I

2014-06-01

128

Blue light inhibits mycotoxin production and increases total lipids and pigmentation in Alternaria alternata.  

PubMed Central

Light inhibits production of the mycotoxins alternariol and alternariol monomethyl ether, both polyketids produced by Alternaria alternata. This effect seems to be general because seven isolates of A. alternata with different alternariol- and alternariol monomethyl ether-producing abilities all respond to continuous light with reduced levels of alternariol and alternariol monomethyl ether when the mycotoxins were calculated on a microgram-per-milligram (dry weight) basis. Blue light inhibited alternariol and alternariol monomethyl ether production 69 and 77%, respectively. Red light gave no reduction of toxin levels. Total lipids were increased 25% when mycelium was grown in blue light as compared with red light or darkness. In white or blue light, but not in red light or darkness, a red-brown pigment accumulated by the mycelium. PMID:526015

Haggblom, P; Unestam, T

1979-01-01

129

Enhancement of the citrus immune system provides effective resistance against Alternaria brown spot disease.  

PubMed

In addition to basal defense mechanisms, plants are able to develop enhanced defense mechanisms such as induced resistance (IR) upon appropriate stimulation. We recently described the means by which several carboxylic acids protect Arabidopsis and tomato plants against fungi. In this work, we demonstrate the effectiveness of hexanoic acid (Hx) in the control of Alternaria brown spot (ABS) disease via enhancement of the immune system of Fortune mandarin. The application of 1mM Hx in irrigation water to 2-year-old Fortune plants clearly reduced the incidence of the disease and led to smaller lesions. We observed that several of the most important mechanisms involved in induced resistance were affected by Hx application. Our results demonstrate enhanced callose deposition in infected plants treated with Hx, which suggests an Hx priming mechanism. Plants treated with the callose inhibitor 2-DDG were more susceptible to the fungus. Moreover, polygalacturonase-inhibiting protein (PGIP) gene expression was rapidly and significantly upregulated in treated plants. However, treatment with Hx decreased the levels of reactive oxygen species (ROS) in infected plants. Hormonal and gene analyses revealed that the jasmonic acid (JA) pathway was activated due to a greater accumulation of 12-oxo-phytodienoic acid (OPDA) and JA along with a rapid accumulation of JA-isoleucine (JA-Ile). Furthermore, we observed a more rapid accumulation of abscisic acid (ABA), which could act as a positive regulator of callose deposition. Thus, our results support the hypothesis that both enhanced physical barriers and the JA signaling pathway are involved in hexanoic acid-induced resistance (Hx-IR) to Alternaria alternata. PMID:23260526

Llorens, Eugenio; Fernández-Crespo, Emma; Vicedo, Begonya; Lapeña, Leonor; García-Agustín, Pilar

2013-01-15

130

Stem Cells and Diseases  

MedlinePLUS

... Can Stem Cells Help my Medical Condition? Stem Cell Information Frequently Asked Questions What are stem cells? ... policy? More FAQs Links to related resources Stem Cell Research Center for Regenerative Medicine NIH Stem Cell ...

131

Population Structure of Geosmithia morbida, the Causal Agent of Thousand Cankers Disease of Walnut Trees in the United States  

PubMed Central

The ascomycete Geosmithia morbida and the walnut twig beetle Pityophthorus juglandis are associated with thousand cankers disease of Juglans (walnut) and Pterocarya (wingnut). The disease was first reported in the western United States (USA) on several Juglans species, but has been found more recently in the eastern USA in the native range of the highly susceptible Juglans nigra. We performed a comprehensive population genetic study of 209 G. morbida isolates collected from Juglans and Pterocarya from 17 geographic regions distributed across 12 U.S. states. The study was based on sequence typing of 27 single nucleotide polymorphisms from three genomic regions and genotyping with ten microsatellite primer pairs. Using multilocus sequence-typing data, 197 G. morbida isolates were placed into one of 57 haplotypes. In some instances, multiple haplotypes were recovered from isolates collected on the same tree. Twenty-four of the haplotypes (42%) were recovered from more than one isolate; the two most frequently occurring haplotypes (H02 and H03) represented 36% of all isolates. These two haplotypes were abundant in California, but were not recovered from Arizona or New Mexico. G. morbida population structure was best explained by four genetically distinct groups that clustered into three geographic regions. Most of the haplotypes isolated from the native range of J. major (Arizona and New Mexico) were found in those states only or present in distinct genetic clusters. There was no evidence of sexual reproduction or genetic recombination in any population. The scattered distribution of the genetic clusters indicated that G. morbida was likely disseminated to different regions at several times and from several sources. The large number of haplotypes observed and the genetic complexity of G. morbida indicate that it evolved in association with at least one Juglans spp. and the walnut twig beetle long before the first reports of the disease. PMID:25393300

Graves, Andrew D.; Hartel, Colleen; Pscheidt, Jay W.; Tonos, Jadelys; Broders, Kirk; Cranshaw, Whitney; Seybold, Steven J.; Tisserat, Ned

2014-01-01

132

Effect of acidic solutions and acidic prochloraz on the control of postharvest decay caused by Alternaria alternata in mango and persimmon fruit  

Microsoft Academic Search

The effectiveness of treatments with hydrochloric acid (HCl), alone or in combination with prochloraz, in controlling quiescent infections of Alternaria alternata that cause alternaria rot in mango and persimmon fruit during storage, were compared. Spore germination and germ-tube elongation of A. alternata in vitro were inhibited by 95 and 65%, respectively, by exposure to 1.25mM HCl, and fungal germination was

D. Prusky; I. Kobiler; M. Akerman; I. Miyara

2006-01-01

133

Restoring stemness.  

PubMed

This essay is focused on a specific line of research toward regenerative therapies that is based on the use of embryonic stem cells but tries to avoid cloning techniques that are the heart of current ethical debates. PMID:16351688

Westphal, Heiner

2005-12-01

134

Effect of climate change on Alternaria leaf spot of rocket salad and black spot of basil under controlled environment.  

PubMed

Plant responses to elevated CO2 and temperature have been much studied in recent years, but effects of climate change on pathological responses are still largely unknown. The pathosystems rocket (Eruca vesicaria subsp. sativa)--Alternaria leaf spot (Alternaria japonica) and basil (Ocimum basilicum)--black spot (Colletotrichum gloeosporioides) were chosen as models to assess the potential impact of increased CO2 and temperature on disease incidence and severity under controlled environment. Potted plants were grown in phytotrons under 4 different simulated climatic conditions: (1) standard temperature (ranging from 18 degrees to 22 degrees C) and standard CO2 concentration (400 ppm); (2) standard temperature and elevated CO2 concentration (800 ppm); (3) elevated temperature (ranging from 22 degrees to 26 degrees C, 4 degrees C higher than standard) and standard CO2 concentration; (4) elevated temperature and CO2 concentration. Each plant was inoculated with a spore suspension containing 1 x 10(5) cfu/ml of the pathogen. Disease incidence and severity were assessed 14 days after inoculation. Increasing CO2 to 800 ppm showed a clear increment in the percentage of Alternaria leaf spot on rocket leaves compared to standard conditions. Basil plants grown at 800 ppm of CO2 showed increased black spot symptoms compared to 400 ppm. Disease incidence and severity were always influenced by the combination of rising CO2 and increased temperature, compared to standard conditions (400 ppm of CO2 - 22 degrees C). Considering the rising concentrations of CO2 and global temperature, we can assume that this could increase the severity of Alternaria japonica on rocket and Colletotrichum gloeosporioides on basil. PMID:23878979

Pugliese, M; Cogliati, E; Gullino, M L; Garibaldi, A

2012-01-01

135

Analysis of global gene expression changes in human bronchial epithelial cells exposed to spores of the allergenic fungus, Alternaria alternata  

PubMed Central

Exposure and sensitivity to ubiquitous airborne fungi such as Alternaria alternata have long been implicated in the development, onset, and exacerbation of chronic allergic airway disorders. This present study is the first to investigate global changes in host gene expression during the interaction of cultured human bronchial epithelial cells and live Alternaria spores. In in vitro experiments human bronchial epithelial cells (BEAS-2B) were exposed to spores or media alone for 24 h. RNA was collected from three biological replicates per treatment and was used to assess changes in gene expression patterns using Affymetrix Human Genome U133 Plus 2.0 Arrays. In cells treated with Alternaria spores compared to controls, 613 probe sets representing 460 individual genes were found differentially expressed (p ? 0.05). In this set of 460 statistically significant, differentially expressed genes, 397 genes were found to be up-regulated and 63 were down-regulated. Of these 397 up-regulated genes, 156 genes were found to be up-regulated ?2 fold. Interestingly, none of the 63 down-regulated genes were found differentially expressed at ??2 fold. Differentially expressed genes were identified following statistical analysis and subsequently used for pathway and network evaluation. Interestingly, many cytokine and chemokine immune response genes were up-regulated with a particular emphasis on interferon-inducible genes. Genes involved in cell death, retinoic acid signaling, and TLR3 response pathways were also significantly up-regulated. Many of the differentially up-regulated genes have been shown in other systems to be associated with innate immunity, inflammation and/or allergic airway diseases. This study now provides substantial information for further investigating specific genes and innate immune system pathways activated by Alternaria in the context of allergic airway diseases. PMID:23882263

Babiceanu, M. C.; Howard, B. A.; Rumore, A. C.; Kita, H.; Lawrence, C. B.

2013-01-01

136

Selection and differentiation of Bacillus spp. Antagonistic to Fusarium oxysporum f.sp. lycopersici and Alternaria solani infecting Tomato  

Microsoft Academic Search

Antagonistic Bacillus spp. displaying in vitro production of siderophore, chitinase, and ?-1,3-glucanase were identified from dual culture assays.\\u000a In independent greenhouse studies, seed bacterization and soil application of Bacillus atrophaeus S2BC-2 challenge inoculated with Fusarium oxysporum f.sp. lycopersici (FOL) and Alternaria solani (AS) recorded low percent disease index of 25.3 and 28.7, respectively, over nonbacterised pathogen control (44.3 and 56.4).

Veerubommu Shanmugam; Kamini Atri; Samriti Gupta; Nandina Kanoujia; Digvijay Singh Naruka

2011-01-01

137

Similar and distinct roles of NADPH oxidase components in the tangerine pathotype of Alternaria alternata.  

PubMed

The fungal nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) complex, which has been implicated in the production of low-level reactive oxygen species (ROS), contains mainly NoxA, NoxB (gp91(phox) homologues) and NoxR (p67(phox) homologue). Here, we report the developmental and pathological functions of NoxB and NoxR in the tangerine pathotype of Alternaria alternata. Loss-of-function genetics revealed that all three Nox components are required for the accumulation of cellular hydrogen peroxide (H?O?). Alternaria alternata strains lacking NoxA, NoxB or NoxR also displayed an increased sensitivity to H?O? and many ROS-generating oxidants. These phenotypes are highly similar to those previously seen for the ?yap1 mutant lacking a YAP1 transcriptional regulator and for the ?hog1 mutant lacking a HOG1 mitogen-activated protein (MAP) kinase, implicating a possible link among them. A fungal strain carrying a NoxA NoxB or NoxA NoxR double mutation was more sensitive to the test compounds than the strain mutated at a single gene, implicating a synergistic function among Nox components. The ?noxB mutant strain failed to produce any conidia; both ?noxA and ?noxR mutant strains showed a severe reduction in sporulation. Mutant strains carrying defective NoxB had higher chitin content than the wild-type and were insensitive to calcofluor white, Congo red and the fungicides vinclozolin and fludioxonil. Virulence assays revealed that all three Nox components are required for the elaboration of the penetration process. The inability to penetrate the citrus host, observed for ?nox mutants, could be overcome by wounding and by reacquiring a dominant Nox gene. The A.?alternata?NoxR did not influence the expression of NoxB, but negatively regulated NoxA. Importantly, the expression of both YAP1 and HOG1 genes, whose products are involved in resistance to ROS, was down-regulated in fungi carrying defective NoxA, NoxB or NoxR. Our results highlight the requirement of Nox in ROS resistance and provide insights into its critical role in regulating both YAP1 and HOG1 in A.?alternata. PMID:23527595

Yang, Siwy Ling; Chung, Kuang-Ren

2013-08-01

138

Stress Response and Pathogenicity of the Necrotrophic Fungal Pathogen Alternaria alternata  

PubMed Central

The production of host-selective toxins by the necrotrophic fungus Alternaria alternata is essential for the pathogenesis. A. alternata infection in citrus leaves induces rapid lipid peroxidation, accumulation of hydrogen peroxide (H2O2), and cell death. The mechanisms by which A. alternata avoids killing by reactive oxygen species (ROS) after invasion have begun to be elucidated. The ability to coordinate of signaling pathways is essential for the detoxification of cellular stresses induced by ROS and for pathogenicity in A. alternata. A low level of H2O2, produced by the NADPH oxidase (NOX) complex, modulates ROS resistance and triggers conidiation partially via regulating the redox-responsive regulators (YAP1 and SKN7) and the mitogen-activated protein (MAP) kinase (HOG1) mediated pathways, which subsequently regulate the genes required for the biosynthesis of siderophore, an iron-chelating compound. Siderophore-mediated iron acquisition plays a key role in ROS detoxification because of the requirement of iron for the activities of antioxidants (e.g., catalase and SOD). Fungal strains impaired for the ROS-detoxifying system severely reduce the virulence on susceptible citrus cultivars. This paper summarizes the current state of knowledge of signaling pathways associated with cellular responses to multidrugs, oxidative and osmotic stress, and fungicides, as well as the pathogenicity/virulence in the tangerine pathotype of A. alternata. PMID:24278721

Chung, Kuang-Ren

2012-01-01

139

Stress Response and Pathogenicity of the Necrotrophic Fungal Pathogen Alternaria alternata.  

PubMed

The production of host-selective toxins by the necrotrophic fungus Alternaria alternata is essential for the pathogenesis. A. alternata infection in citrus leaves induces rapid lipid peroxidation, accumulation of hydrogen peroxide (H2O2), and cell death. The mechanisms by which A. alternata avoids killing by reactive oxygen species (ROS) after invasion have begun to be elucidated. The ability to coordinate of signaling pathways is essential for the detoxification of cellular stresses induced by ROS and for pathogenicity in A. alternata. A low level of H2O2, produced by the NADPH oxidase (NOX) complex, modulates ROS resistance and triggers conidiation partially via regulating the redox-responsive regulators (YAP1 and SKN7) and the mitogen-activated protein (MAP) kinase (HOG1) mediated pathways, which subsequently regulate the genes required for the biosynthesis of siderophore, an iron-chelating compound. Siderophore-mediated iron acquisition plays a key role in ROS detoxification because of the requirement of iron for the activities of antioxidants (e.g., catalase and SOD). Fungal strains impaired for the ROS-detoxifying system severely reduce the virulence on susceptible citrus cultivars. This paper summarizes the current state of knowledge of signaling pathways associated with cellular responses to multidrugs, oxidative and osmotic stress, and fungicides, as well as the pathogenicity/virulence in the tangerine pathotype of A. alternata. PMID:24278721

Chung, Kuang-Ren

2012-01-01

140

Multiple phytohormone signalling pathways modulate susceptibility of tomato plants to Alternaria alternata f. sp. lycopersici  

PubMed Central

Three phytohormone molecules – ethylene (ET), jasmonic acid (JA) and salicylic acid (SA) – play key roles in mediating disease response to necrotrophic fungal pathogens. This study investigated the roles of the ET, JA, and SA pathways as well as their crosstalk during the interaction between tomato (Solanum lycopersicum) plants and a necrotrophic fungal pathogen Alternaria alternata f. sp. lycopersici (AAL). Both the ET and JASMONIC ACID INSENSITIVE1 (JAI1) receptor-dependent JA signalling pathways are necessary for susceptibility, while SA response promotes resistance to AAL infection. In addition, the role of JA in susceptibility to AAL is partly dependent on ET biosynthesis and perception, while the SA pathway enhances resistance to AAL and antagonizes the ET response. Based on these results, it is proposed that ET, JA, and SA each on their own can influence the susceptibility of tomato to AAL. Furthermore, the functions of JA and SA in susceptibility to the pathogen are correlated with the enhanced or decreased action of ET, respectively. This study has revealed the functional relationship among the three key hormone pathways in tomato defence against AAL. PMID:23264518

Jia, Chengguo; Zhang, Liping; Wang, Qiaomei

2013-01-01

141

Secretome Analysis Reveals an Arabidopsis Lipase Involved in Defense against Alternaria brassicicolaW?  

PubMed Central

The Arabidopsis thaliana secretome was analyzed by the proteomic approach, which led to the identification of secreted proteins implicated in many aspects of cell biology. We then investigated the change in the Arabidopsis secretome in response to salicylic acid and identified several proteins involved in pathogen response. One of these, a secreted lipase with a GDSL-like motif designated GDSL LIPASE1 (GLIP1), was further characterized for its function in disease resistance. glip1 plants were markedly more susceptible to infection by the necrotrophic fungus Alternaria brassicicola compared with the parental wild-type plants. The recombinant GLIP1 protein possessed lipase and antimicrobial activities that directly disrupt fungal spore integrity. Furthermore, GLIP1 appeared to trigger systemic resistance signaling in plants when challenged with A. brassicicola, because pretreatment of the glip1 mutant with recombinant GLIP1 protein inhibited A. brassicicola–induced cell death in both peripheral and distal leaves. Moreover, glip1 showed altered expression of defense- and ethylene-related genes. GLIP1 transcription was increased by ethephon, the ethylene releaser, but not by salicylic acid or jasmonic acid. These results suggest that GLIP1, in association with ethylene signaling, may be a critical component in plant resistance to A. brassicicola. PMID:16126835

Oh, Il Seok; Park, Ae Ran; Bae, Min Seok; Kwon, Sun Jae; Kim, Young Soon; Lee, Ji Eun; Kang, Na Young; Lee, Sumin; Cheong, Hyeonsook; Park, Ohkmae K.

2005-01-01

142

STEM Transitions  

NSDL National Science Digital Library

Under the direction of the Center for Occupational Research and Development (CORD), the STEM Transitions initiative has worked with 40 community college faculty to create integrated curriculum projects for use in math, science, and technical courses in the six STEM-related clusters. Much of this work has been funded by the U.S. Department of Education's Office of Vocational and Adult Education. First-time visitors can get an overview in the "Using This Site" area and then visit the "Integrated Projects" area. After signing up for a free account, they can take advantage of over 60 lesson plans and activities such as "The Secret Ingredient: Nutrient Analysis of Selected Food Items" and "Good Dirty, Bad Dirty: Soil Types and Erosion Potential." The site also provides information about upcoming webinars and workshops sponsored by the STEM Transitions, along with information about their faculty affiliates.

143

Fitness cost of virulence differs between the AvrLm1 and AvrLm4 loci in Leptosphaeria maculans (phoma stem canker of oilseed rape)  

Microsoft Academic Search

To investigate whether the reported fitness cost of virulence at the AvrLm4 locus in Leptosphaeria maculans is common to other loci, near-isogenic (NI) isolates differing at AvrLm1 locus were produced in vitro. Fitness of virulent (avrLm1) or avirulent (AvrLm1) isolates on Brassica napus without the corresponding R (resistance) gene Rlm1 was investigated in controlled environment (CE) and field experiments. Results

Yong-Ju Huang; Marie-Hélène Balesdent; Zi-Qin Li; Neal Evans; Thierry Rouxel; Bruce D. L. Fitt

2010-01-01

144

Isolation and characterization of the grain mold fungi Cochliobolus and Alternaria spp. from sorghum using semiselective media and DNA sequence analyses.  

PubMed

Mold diseases, caused by fungal complexes including Alternaria, Cochliobolus, and Fusarium species, limit sorghum grain production. Media were tested by plating Fusarium thapsinum, Alternaria sp., and Curvularia lunata, individually and competitively. Dichloran chloramphenicol rose bengal (DRBC) and modified V8 juice (ModV8) agars, found to be useful, were compared with commonly used agar media, dichloran chloramphenicol peptone (DCPA) and pentachloronitrobenzene (PCNB). Radial growth, starting with mycelia or single-conidia and hyphal tips, demonstrated an effect of media. For isolation of grain fungi, DRBC and ModV8 were similar or superior to DCPA and PCNB. When seedlings were inoculated with conidia of C. lunata, Alternaria sp., F. thapsinum, or mixtures, the percentage of root infection ranged from 28% to 77%. For mixed inoculations, shoot weights, lesion lengths, and percentage of root infections were similar to F. thapsinum inoculations; most colonies recovered from roots were F. thapsinum. For Alternaria grain isolates, 5 morphological types, including Alternaria alternata, were distinguished by colony morphologies and conidial dimensions. Sequence analysis using a portion of the endo-polygalacturonase gene was able to further distinguish isolates. Cochliobolus isolates were identified morphologically as C. lunata, Curvularia sorghina, and Bipolaris sorghicola. Multiple molecular genotypes were apparent from rRNA internal transcribed spacer region sequences from Cochliobolus grain isolates. PMID:23461515

Funnell-Harris, Deanna L; Prom, Louis K; Pedersen, Jeffrey F

2013-02-01

145

Transcription Factor Amr1 Induces Melanin Biosynthesis and Suppresses Virulence in Alternaria brassicicola  

PubMed Central

Alternaria brassicicola is a successful saprophyte and necrotrophic plant pathogen. Several A. brassicicola genes have been characterized as affecting pathogenesis of Brassica species. To study regulatory mechanisms of pathogenesis, we mined 421 genes in silico encoding putative transcription factors in a machine-annotated, draft genome sequence of A. brassicicola. In this study, targeted gene disruption mutants for 117 of the transcription factor genes were produced and screened. Three of these genes were associated with pathogenesis. Disruption mutants of one gene (AbPacC) were nonpathogenic and another gene (AbVf8) caused lesions less than half the diameter of wild-type lesions. Unexpectedly, mutants of the third gene, Amr1, caused lesions with a two-fold larger diameter than the wild type and complementation mutants. Amr1 is a homolog of Cmr1, a transcription factor that regulates melanin biosynthesis in several fungi. We created gene deletion mutants of ?amr1 and characterized their phenotypes. The ?amr1 mutants used pectin as a carbon source more efficiently than the wild type, were melanin-deficient, and more sensitive to UV light and glucanase digestion. The AMR1 protein was localized in the nuclei of hyphae and in highly melanized conidia during the late stage of plant pathogenesis. RNA-seq analysis revealed that three genes in the melanin biosynthesis pathway, along with the deleted Amr1 gene, were expressed at low levels in the mutants. In contrast, many hydrolytic enzyme-coding genes were expressed at higher levels in the mutants than in the wild type during pathogenesis. The results of this study suggested that a gene important for survival in nature negatively affected virulence, probably by a less efficient use of plant cell-wall materials. We speculate that the functions of the Amr1 gene are important to the success of A. brassicicola as a competitive saprophyte and plant parasite. PMID:23133370

Cho, Yangrae; Srivastava, Akhil; Ohm, Robin A.; Lawrence, Christopher B.; Wang, Koon-Hui; Grigoriev, Igor V.; Marahatta, Sharadchandra P.

2012-01-01

146

The influence of different nitrogen and carbon sources on mycotoxin production in Alternaria alternata.  

PubMed

The aim of this study was to determine the influence of different carbon and nitrogen sources on the production of the mycotoxins alternariol (AOH), alternariol monomethyl ether (AME) and tenuazonic acid (TA) by Alternaria alternata at 28°C using a semi-synthetic medium (modified Czapek-Dox broth) supplemented with nitrogen and carbon sources. Additionally the effect of shaken and static cultivation on mycotoxin production was tested. Initial experiments showed a clear dependency between nitrogen depletion and mycotoxin production. To assess whether nitrogen limitation in general or the type of nitrogen source triggers the production, various nitrogen sources including several ammonium/nitrate salts and amino acids were tested. In static culture the production of AOH/AME can be enhanced greatly with phenylalanine whereas some nitrogen sources seem to inhibit the AOH/AME production completely. TA was not significantly affected by the choice of nitrogen source. In shaken culture the overall production of all mycotoxins was lower compared to static cultivation. Furthermore tests with a wide variety of carbon sources including monosaccharides, disaccharides, complex saccharides such as starch as well as glycerol and acetate were performed. In shaken culture AOH was produced when glucose, fructose, sucrose, acetate or mixtures of glucose/sucrose and glucose/acetate were used as carbon sources. AME production was not detected. The use of sodium acetate resulted in the highest AOH production. In static culture AOH production was also stimulated by acetate and the amount is comparable to shaken conditions. Under static conditions production of AOH was lower except when cultivated with acetate. In static cultivation 9 of 14 tested carbon sources induced mycotoxin production compared to 4 in shaken culture. This is the first study which analyses the influence of carbon and nitrogen sources in a semi-synthetic medium and assesses the effects of culture conditions on mycotoxin production by A. alternata. PMID:21496935

Brzonkalik, Katrin; Herrling, Tanja; Syldatk, Christoph; Neumann, Anke

2011-05-27

147

Elevated Atmospheric Carbon Dioxide Concentrations Amplify Alternaria alternata Sporulation and Total Antigen Production  

PubMed Central

Background Although the effect of elevated carbon dioxide (CO2) concentration on pollen production has been established in some plant species, impacts on fungal sporulation and antigen production have not been elucidated. Objective Our purpose was to examine the effects of rising atmospheric CO2 concentrations on the quantity and quality of fungal spores produced on timothy (Phleum pratense) leaves. Methods Timothy plants were grown at four CO2 concentrations (300, 400, 500, and 600 ?mol/mol). Leaves were used as growth substrate for Alternaria alternata and Cladosporium phlei. The spore abundance produced by both fungi, as well as the size (microscopy) and antigenic protein content (ELISA) of A. alternata, were quantified. Results Leaf carbon-to-nitrogen ratio was greater at 500 and 600 ?mol/mol, and leaf biomass was greater at 600 ?mol/mol than at the lower CO2 concentrations. Leaf carbon-to-nitrogen ratio was positively correlated with A. alternata spore production per gram of leaf but negatively correlated with antigenic protein content per spore. At 500 and 600 ?mol/mol CO2 concentrations, A. alternata produced nearly three times the number of spores and more than twice the total antigenic protein per plant than at lower concentrations. C. phlei spore production was positively correlated with leaf carbon-to-nitrogen ratio, but overall spore production was much lower than in A. alternata, and total per-plant production did not vary among CO2 concentrations. Conclusions Elevated CO2 concentrations often increase plant leaf biomass and carbon-to-nitrogen ratio. Here we demonstrate for the first time that these leaf changes are associated with increased spore production by A. alternata, a ubiquitous allergenic fungus. This response may contribute to the increasing prevalence of allergies and asthma. PMID:20462828

Wolf, Julie; O'Neill, Nichole R.; Rogers, Christine A.; Muilenberg, Michael L.; Ziska, Lewis H.

2010-01-01

148

Modulation of Alternaria infectoria Cell Wall Chitin and Glucan Synthesis by Cell Wall Synthase Inhibitors  

PubMed Central

The present work reports the effects of caspofungin, a ?-1,3-glucan synthase inhibitor, and nikkomycin Z, an inhibitor of chitin synthases, on two strains of Alternaria infectoria, a melanized fungus involved in opportunistic human infections and respiratory allergies. One of the strains tested, IMF006, bore phenotypic traits that conferred advantages in resisting antifungal treatment. First, the resting cell wall chitin content was higher and in response to caspofungin, the chitin level remained constant. In the other strain, IMF001, the chitin content increased upon caspofungin treatment to values similar to basal IMF006 levels. Moreover, upon caspofungin treatment, the FKS1 gene was upregulated in IMF006 and downregulated in IMF001. In addition, the resting ?-glucan content was also different in both strains, with higher levels in IMF001 than in IMF006. However, this did not provide any advantage with respect to echinocandin resistance. We identified eight different chitin synthase genes and studied relative gene expression when the fungus was exposed to the antifungals under study. In both strains, exposure to caspofungin and nikkomycin Z led to modulation of the expression of class V and VII chitin synthase genes, suggesting its importance in the robustness of A. infectoria. The pattern of A. infectoria phagocytosis and activation of murine macrophages by spores was not affected by caspofungin. Monotherapy with nikkomycin Z and caspofungin provided only fungistatic inhibition, while a combination of both led to fungal cell lysis, revealing a strong synergistic action between the chitin synthase inhibitor and the ?-glucan synthase inhibitor against this fungus. PMID:24614372

Fernandes, Chantal; Anjos, Jorge; Walker, Louise A.; Silva, Branca M. A.; Cortes, Luisa; Mota, Marta; Munro, Carol A.; Gow, Neil A. R.

2014-01-01

149

Scopoletin is a phytoalexin against Alternaria alternata in wild tobacco dependent on jasmonate signalling.  

PubMed

Alternaria alternata (tobacco pathotype) is a necrotrophic fungus causing severe losses in Nicotiana species by infection of mature leaves. Similar to what has been observed in cultivated tobacco, N. tabacum, young leaves of wild tobacco, N. attenuata, were more resistant to A. alternata than mature leaves, and this was correlated with stronger blue fluorescence induced after infection. However, the nature of the fluorescence-emitting compound, its role in defence, and its regulation were not clear. Silencing feruloyl-CoA 6'-hydroxylase 1 (F6'H1), the gene encoding the key enzyme for scopoletin biosynthesis, by virus-induced gene silencing (VIGS) revealed that the blue fluorescence was mainly emitted by scopoletin and its ?-glycoside form, scopolin. Further analysis showed that scopoletin exhibited strong antifungal activity against A. alternata in vitro and in vivo. Importantly, jasmonic acid (JA) levels were highly elicited in young leaves but much less in mature leaves after infection; and fungus-elicited scopoletin was absent in JA-deficient plants, but was largely restored with methyl jasmonate treatments. Consistent with this, plants strongly impaired in JA biosynthesis and perception were highly susceptible to A. alternata in the same way scopoletin/scopolin-depleted VIGS F6'H1 plants. Furthermore, silencing MYC2, a master regulator of most JA responses, reduced A. alternata-induced NaF6'H1 transcripts and scopoletin. Thus, it is concluded that JA signalling is activated in N. attenuata leaves after infection, which subsequently regulates scopoletin biosynthesis for the defence against A. alternata partly through MYC2, and higher levels of scopoletin accumulated in young leaves account for their strong resistance. PMID:24821958

Sun, Huanhuan; Wang, Lei; Zhang, Baoqin; Ma, Junhong; Hettenhausen, Christian; Cao, Guoyan; Sun, Guiling; Wu, Jianqiang; Wu, Jinsong

2014-08-01

150

Contrasting Codon Usage Patterns and Purifying Selection at the Mating Locus in Putatively Asexual Alternaria Fungal Species  

PubMed Central

Sexual reproduction in heterothallic ascomycete fungi is controlled by a single mating-type locus called MAT1 with two alternate alleles or idiomorphs, MAT1-1 and MAT1-2. These alleles lack sequence similarity and encode different transcriptional regulators. A large number of phytopathogenic fungi including Alternaria spp. are considered asexual, yet still carry expressed MAT1 genes. The molecular evolution of Alternaria MAT1 was explored using nucleotide diversity, nonsynonymous vs. synonymous substitution (dn/ds) ratios and codon usage statistics. Likelihood ratio tests of site-branch models failed to detect positive selection on MAT1-1-1 or MAT1-2-1. Codon-site models demonstrated that both MAT1-1-1 and MAT1-2-1 are under purifying selection and significant differences in codon usage were observed between MAT1-1-1 and MAT1-2-1. Mean GC content at the third position (GC3) and effective codon usage (ENC) were significantly different between MAT1-1-1 and MAT1-2-1 with values of 0.57 and 48 for MAT1-1-1 and 0.62 and 46 for MAT1-2-1, respectively. In contrast, codon usage of Pleospora spp. (anamorph Stemphylium), a closely related Dothideomycete genus, was not significantly different between MAT1-1-1 and MAT1-2-1. The purifying selection and biased codon usage detected at the MAT1 locus in Alternaria spp. suggest a recent sexual past, cryptic sexual present and/or that MAT1 plays important cellular role(s) in addition to mating. PMID:21625561

Stewart, Jane E.; Kawabe, Masato; Abdo, Zaid; Arie, Tsutomu; Peever, Tobin L.

2011-01-01

151

Cell Stem Cell Stem Cell States, Fates,  

E-print Network

and Stem Cell Research, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, Lund SE-223 62, Sweden 4Lund Strategic Research Center for Stem Cell Biology and Cell Therapy, LundCell Stem Cell Review Stem Cell States, Fates, and the Rules of Attraction Tariq Enver,1 Martin

Peterson, Carsten

152

Gamma-pyrone derivatives, kojic acid methyl ethers from a marine-derived fungus Alternaria [correction of Altenaria] sp.  

PubMed

Kojic acid dimethyl ether (1), and the known kojic acid monomethyl ether (2), kojic acid (3) and phomaligol A (4) have been isolated from the organic extract of the broth of the marine-derived fungus Alternaria sp. collected from the surface of the marine green alga Ulva pertusa. The structures were assigned on the basis of comprehensive spectroscopic analyses. Each isolate was tested for its tyrosinase inhibitory activity. Kojic acid (3) was found to have significant tyrosinase inhibitory activity, but compounds 1, 2, and 4 were found to be inactive. PMID:12934644

Li, Xifeng; Jeong, Jee Hean; Lee, Kang Tae; Rho, Jung Rae; Choi, Hong Dae; Kang, Jung Sook; Son, Byeng Wha

2003-07-01

153

Apoptosis: A Functional Paradigm for Programmed Plant Cell Death Induced by a Host-Selective Phytotoxin and Invoked during Development.  

PubMed Central

The host-selective AAL toxins secreted by Alternaria alternata f sp lycopersici are primary chemical determinants in the Alternaria stem canker disease of tomato. The AAL toxins are members of a new class of sphinganine analog mycotoxins that cause cell death in both animals and plants. Here, we report detection of stereotypic hallmarks of apoptosis during cell death induced by these toxins in tomato. DNA ladders were observed during cell death in toxin-treated tomato protoplasts and leaflets. The intensity of the DNA ladders was enhanced by Ca2+ and inhibited by Zn2+. The progressive delineation of fragmented DNA into distinct bodies, coincident with the appearance of DNA ladders, also was observed during death of toxin-treated tomato protoplasts. In situ analysis of cells dying during development in both onion root caps and tomato leaf tracheary elements revealed DNA fragmentation localized to the dying cells as well as the additional formation of apoptotic-like bodies in sloughing root cap cells. We conclude that the fundamental elements of apoptosis, as characterized in animals, are conserved in plants. The apoptotic process may be expressed during some developmental transitions and is the functional process by which symptomatic lesions are formed in the Alternaria stem canker disease of tomato. Sphinganine analog mycotoxins may be used to characterize further signaling pathways leading to apoptosis in plants. PMID:12239387

Wang, H; Li, J; Bostock, RM; Gilchrist, DG

1996-01-01

154

Dissection of the host range of the fungal plant pathogen Alternaria alternata by modification of secondary metabolism.  

PubMed

The filamentous fungus Alternaria alternata contains seven pathogenic variants (pathotypes), which produce different host-specific toxins and cause diseases on different plants. The strawberry pathotype produces host-specific AF-toxin and causes Alternaria black spot of strawberry. This pathotype is also pathogenic to Japanese pear cultivars susceptible to the Japanese pear pathotype that produces AK-toxin. The strawberry pathotype produces two related molecular species, AF-toxins I and II: toxin I is toxic to both strawberry and pear, and toxin II is toxic only to pear. Previously, we isolated a cosmid clone pcAFT-1 from the strawberry pathotype that contains three genes involved in AF-toxin biosynthesis. Here, we have identified a new gene, designated AFTS1, from pcAFT-1. AFTS1 encodes a protein with similarity to enzymes of the aldo-ketoreductase superfamily. Targeted mutation of AFTS1 diminished the host range of the strawberry pathotype: Delta aftS1 mutants were pathogenic to pear, but not to strawberry, as is the Japanese pear pathotype. These mutants were found to produce AF-toxin II, but not AF-toxin I. These data represent a novel example of how the host range of a plant pathogenic fungus can be restricted by modification of secondary metabolism. PMID:15066029

Ito, Kaoru; Tanaka, Takayoshi; Hatta, Rieko; Yamamoto, Mikihiro; Akimitsu, Kazuya; Tsuge, Takashi

2004-04-01

155

Stem Cell Transplants  

MedlinePLUS

What Are Stem Cells? As you probably remember from biology class, every living thing is made up of cells — including the human body. ... can become new cells like this. Blood Stem Cells When you hear about stem cell transplants, they ...

156

Stem Up  

NSDL National Science Digital Library

Stem Up is a pilot program to aid the disadvantaged youth of Boyle Heights in Los Angeles. The intent of the program was to integrate STEM career pathways into schools and local communities. Visitors will find the K-12 Students tab near the top of the page to be filled with almost two dozen links for all levels of student learning about science and technology. Some of the sites include "Arrick Robotics", for 9-12 graders, "Extreme Science", for all ages, and "Fun Engineering" for kids aged 10-14. The "Boyle Heights" link is a great resource for residents of the LA neighborhood, as well as informative for those visitors unfamiliar with it. There is full contact information for the city and state representatives of the neighborhood, the Police Activities League, and a live theatre that performs outreach through theatre, and classical plays. The "Parents" link also provides a number of science and technology links that parents and kids can visit together.

157

Occurrence of Cladosporium spp. and Alternaria spp. spores in Western, Northern and Central-Eastern Poland in 2004-2006 and relation to some meteorological factors  

NASA Astrophysics Data System (ADS)

The concentration of airborne spores of Cladosporium spp. and Alternaria spp. has been investigated at three monitoring stations situated along the west-north and central-east transect in Poland (Szczecin, Olsztyn, Warszawa,) i.e. from a height of 100 m to 149 m above sea level. The aerobiological monitoring of fungal spores was performed by means of three Lanzoni volumetric spore traps. Cladosporium spp. spores were dominant at all the stations. The highest Cladosporium spp. and Alternaria spp. numbers of spores were observed at all the cities in July and August. Statistically significant correlations have been found between the Cladosporium spp. and Alternaria spp. concentration in the air and the mean air temperature, amount of precipitation, air pressure and relative air humidity. The spore count of Cladosporium spp. and Alternaria spp. is determined by the diversity of local flora and weather conditions, especially by the air temperature. The identification of factors, which influence and shape spore concentrations, may significantly improve the current methods of allergy prevention.

Grinn-Gofro?, Agnieszka; Rapiejko, Piotr

2009-08-01

158

Alternaria toxin-induced resistance against rose aphids and olfactory response of aphids to toxin-induced volatiles of rose plants*  

PubMed Central

The search for active toxins for managing weeds or plant diseases is believed to be a promising avenue of investigation. However, the effects of Alternaria toxins on insects have just begun to be investigated. Bioactivities of toxins from four strains of Alternaria alternata on Rosa chinensis and rose aphid Macrosiphum rosivorum were tested in the present study. At a concentration of 50.0 ?g/ml, the crude extract (toxin) of strain 7484 was found not to be harmful to rose plants with excised leaf-puncture method (P?0.079), and rose plants showed enhanced resistance to rose aphids when this Alternaria toxin was sprayed on the plants (P?0.001). However, this toxin caused no detrimental effects on aphids in insecticidal bioassay at a concentration of 10.0 to 160.0 ?g/ml (P?0.096). Therefore, the Alternaria toxin had significantly induced the resistance of rose plants against rose aphids, demonstrating that the resistance mechanism triggered by the Alternaria toxin in the rose plant may also be used by the plant to defend itself against insects. Further bioassays aimed to discover the olfactory responses of aphids to the toxin-induced volatiles of host plants. The aphids were significantly more attracted to both volatiles emitted and collected from control rose plants than to both volatiles emitted and collected from the toxin-treated rose plants (P?0.014). This result showed that the toxin-induced resistance related to the volatile changes of host plants. PMID:22302426

Yang, Fa-zhong; Li, Li; Yang, Bin

2012-01-01

159

The Anthraquinone Derivatives from the Fungus Alternaria sp. XZSBG-1 from the Saline Lake in Bange, Tibet, China.  

PubMed

Four new anthraquinone derivatives 1-4 were obtained along with seven known compounds 5-11 from the extracts of the fungal strain Alternaria sp. XZSBG-1 which was isolated from the sediments of the carbonate saline lake in Bange, Tibet, China. Their structures were determined by spectroscopic methods, mainly by 2D NMR spectra. Compound 1 is a novel tetrahydroanthraquinone with an epoxy ether bond between C-4a and C-9a. In the primary bioassays, compound 3 (alterporriol T) exhibited inhibition of a-glucosidase with a IC50 value 7.2 ?M, and compound 9 showed good inhibitory activity against the HCT-116 and HeLa cell lines, with IC50 values of 3.03 and 8.09 ?M, respectively. PMID:25317580

Chen, Bin; Shen, Qiong; Zhu, Xun; Lin, Yongcheng

2014-01-01

160

Seven naphtho-?-pyrones from the marine-derived fungus Alternaria alternata: structure elucidation and biological properties  

PubMed Central

Eight bioactive pyrone derivatives were identified from the culture of Alternaria alternata strain D2006, isolated from the marine soft coral Denderonephthya hemprichi, which was selected as its profound antimicrobial activities. The compounds were assigned as pyrophen (1), rubrofusarin B (2), fonsecin (3), and fonsecin B (5) beside to the four dimeric naphtho-?-pyrones; aurasperone A (6), aurasperone B (7), aurasperone C (8), and aurasperone F (9). Structures of the isolated compounds were identified on the basis of 1D and 2D NMR spectroscopy and mass (EI, ESI, HRESI) data, and by comparison with the literature. Configuration of the four dimeric naphtho-?-pyrones 6-9 was analyzed by CD spectra, exhibiting an identical stereochemistry. PMID:22377027

2012-01-01

161

Spatial and temporal distribution of Alternaria spores in the Iberian Peninsula atmosphere, and meteorological relationships: 1993-2009  

NASA Astrophysics Data System (ADS)

This paper provides an updated of airborne Alternaria spore spatial and temporal distribution patterns in the Iberian Peninsula, using a common non-viable volumetric sampling method. The highest mean annual spore counts were recorded in Sevilla (39,418 spores), Mérida (33,744) and Málaga (12,947), while other sampling stations never exceeded 5,000. The same cities also recorded the highest mean daily spore counts (Sevilla 109 spores m-3; Mérida 53 spores m-3 and Málaga 35 spores m-3) and the highest number of days on which counts exceeded the threshold levels required to trigger allergy symptoms (Sevilla 38 % and Mérida 30 % of days). Analysis of annual spore distribution patterns revealed either one or two peaks, depending on the location and prevailing climate of sampling stations. For all stations, average temperature was the weather parameter displaying the strongest positive correlation with airborne spore counts, whilst negative correlations were found for rainfall and relative humidity.

Aira, María-Jesús; Rodríguez-Rajo, Francisco-Javier; Fernández-González, María; Seijo, Carmen; Elvira-Rendueles, Belén; Abreu, Ilda; Gutiérrez-Bustillo, Montserrat; Pérez-Sánchez, Elena; Oliveira, Manuela; Recio, Marta; Tormo, Rafael; Morales, Julia

2013-03-01

162

Dental Pulp Stem Cells  

Microsoft Academic Search

Postnatal stem cells have been isolated from a variety of tissues. These stem cells are thought to possess great therapeutic potential for repairing damaged and\\/or defective tissues. Clinically, hematopoietic stem cells have been successfully used for decades in the treatment of various diseases and disorders. However, the therapeutic potential of other postnatal stem cell populations has yet to be realized,

He Liu; Stan Gronthos; Songtao Shi

2006-01-01

163

Stem cells in urology  

Microsoft Academic Search

The shortage of donors for organ transplantation has stimulated research on stem cells as a potential resource for cell-based therapy in all human tissues. Stem cells have been used for regenerative medicine applications in many organ systems, including the genitourinary system. The potential applications for stem cell therapy have, however, been restricted by the ethical issues associated with embryonic stem

Tamer Aboushwareb; Anthony Atala

2008-01-01

164

Toward ‘SMART’ stem cells  

Microsoft Academic Search

Stem cell research is at the heart of regenerative medicine, which holds great promise for the treatment of many devastating disorders. However, in addition to hurdles posed by well-publicized ethical issues, this emerging field presents many biological challenges. What is a stem cell? How are embryonic stem cells different from adult stem cells? What are the physiological bases for therapeutically

T Cheng

2008-01-01

165

Stem Cell Image Library  

NSDL National Science Digital Library

The mission of the Stem Cell Resources website is "to provide timely, reliable, high-quality and scientifically credible stem cell information for the educational community worldwide." This section of their site, the Stem Cell Image Library, presents a collection of microscope images of stem cells in various phases.

2012-11-13

166

Dual Roles of Reactive Oxygen Species and NADPH Oxidase RBOHD in an Arabidopsis-Alternaria Pathosystem1[W  

PubMed Central

Arabidopsis (Arabidopsis thaliana) NADPH oxidases have been reported to suppress the spread of pathogen- and salicylic acid-induced cell death. Here, we present dual roles of RBOHD (for respiratory burst oxidase homolog D) in an Arabidopsis-Alternaria pathosystem, suggesting either initiation or prevention of cell death dependent on the distance from pathogen attack. Our data demonstrate that a rbohD knockout mutant exhibits increased spread of cell death at the macroscopic level upon inoculation with the fungus Alternaria brassicicola. However, the cellular patterns of reactive oxygen species accumulation and cell death are fundamentally different in the AtrbohD mutant compared with the wild type. Functional RBOHD causes marked extracellular hydrogen peroxide accumulation as well as cell death in distinct, single cells of A. brassicicola-infected wild-type plants. This single cell response is missing in the AtrbohD mutant, where infection triggers spreading-type necrosis preceded by less distinct chloroplastic hydrogen peroxide accumulation in large clusters of cells. While the salicylic acid analog benzothiadiazole induces the action of RBOHD and the development of cell death in infected tissues, the ethylene inhibitor aminoethoxyvinylglycine inhibits cell death, indicating that both salicylic acid and ethylene positively regulate RBOHD and cell death. Moreover, A. brassicicola-infected AtrbohD plants hyperaccumulate ethylene and free salicylic acid compared with the wild type, suggesting negative feedback regulation of salicylic acid and ethylene by RBOHD. We propose that functional RBOHD triggers death in cells that are damaged by fungal infection but simultaneously inhibits death in neighboring cells through the suppression of free salicylic acid and ethylene levels. PMID:19726575

Pogany, Miklos; von Rad, Uta; Grun, Sebastian; Dongo, Anita; Pintye, Alexandra; Simoneau, Philippe; Bahnweg, Gunther; Kiss, Levente; Barna, Balazs; Durner, Jorg

2009-01-01

167

Stem Cell Biobanks  

Microsoft Academic Search

Stem cells contribute to innate healing and harbor a promising role for regenerative medicine. Stem cell banking through long-term\\u000a storage of different stem cell platforms represents a fundamental source to preserve original features of stem cells for patient-specific\\u000a clinical applications. Stem cell research and clinical translation constitute fundamental and indivisible modules catalyzed\\u000a through biobanking activity, generating a return of investment.

Silvana Bardelli

2010-01-01

168

Stem cells supporting other stem cells  

PubMed Central

Adult stem cell therapies are increasingly prevalent for the treatment of damaged or diseased tissues, but most of the improvements observed to date are attributed to the ability of stem cells to produce paracrine factors that have a trophic effect on existing tissue cells, improving their functional capacity. It is now clear that this ability to produce trophic factors is a normal and necessary function for some stem cell populations. In vivo adult stem cells are thought to self-renew due to local signals from the microenvironment where they live, the niche. Several niches have now been identified which harbor multiple stem cell populations. In three of these niches – the Drosophila testis, the bulge of the mammalian hair follicle, and the mammalian bone marrow – one type of stem cell has been found to produce factors that contribute to the maintenance of a second stem cell population in the shared niche. In this review, I will examine the architecture of these three niches and discuss the molecular signals involved. Together, these examples establish a new paradigm for stem cell behavior, that stem cells can promote the maintenance of other stem cells. PMID:24348512

Leatherman, Judith

2013-01-01

169

Stable integration and expression of wasabi defensin gene in “Egusi” melon ( Colocynthis citrullus L.) confers resistance to Fusarium wilt and Alternaria leaf spot  

Microsoft Academic Search

Production of “Egusi” melon (Colocynthis citrullus L.) in West Africa is limited by fungal diseases, such as Alternaria leaf spot and Fusarium wilt. In order to engineer “Egusi”\\u000a resistant to these diseases, cotyledonary explants of two “Egusi” genotypes, ‘Ejagham’ and NHC1-130, were transformed with\\u000a Agrobacterium tumefaciens strain EHA101 harbouring wasabi defensin gene (isolated from Wasabia japonica L.) in a binary

Valentine Otang Ntui; Gunaratnam Thirukkumaran; Pejman Azadi; Raham Sher Khan; Ikuo Nakamura; Masahiro Mii

2010-01-01

170

The effect of nano-silver on the activation of nasal polyp epithelial cells by Alternaria, Der P1 and staphylococcal enterotoxin B.  

PubMed

Nano-silver is used for its anti-bacterial, anti-viral and anti-fungal properties. The aim of this study was to investigate the potential clinical efficacy of nano-silver for its anti-inflammatory effect on respiratory epithelial cell inflammation. Primary nasal polyp epithelial cells (NPECs) were exposed to Alternaria alternata, Der P1, and staphylococcal enterotoxin B for 48 h with or without various concentration of nano-silver, then the supernatants were collected. Cell cytotoxicities were measured using a CellTiter-96® aqueous cell proliferation assay kit. The interleukin (IL)-6, IL-8 and granulocyte-macrophage colony stimulating factor were measured to evaluate the inflammatory effects on the epithelial cells. Nuclear factor-?B (NF-?B) and activator protein-1 (AP-1) were analyzed using western blot and ELISA method. Cell survival was found to be significantly decreased at nano-silver concentrations exceeding 10 ppm. Alternaria, Der P1 and SEB activated NPECs with increased cytokine production. Alternaria induced NPECs not inhibited by nano-silver. However, Der P1 and SEB induced cytokine production was significantly affected by concentrations over 1 ppm. Alternaria, Der P1 and SEB enhanced nuclear NF-?B expression and nano-silver inhibited NF-?B expression in SEB and Der P1 treated group. Although nano-silver is cytotoxic at higher concentrations, at safe concentrations it can inhibit the activation of NPECs. This finding suggests a novel pharmacological rationale for the treatment of airway inflammation and/or immunological disease. PMID:21683166

Shin, Seung-Heon; Ye, Mi-Kyung

2011-11-01

171

Induction of ?-1,3-glucanase and chitinase activity in the defense response of Eruca sativa plants against the fungal pathogen Alternaria brassicicola  

Microsoft Academic Search

Plants have developed many mechanisms to protect themselves against most potential microbial pathogens and diseases. Pathogenesis-related proteins are produced as a part of the active defenses to prevent attack. In this study, the induction of PR proteins in Eruca sativa in response to fungal pathogen Alternaria brassicicola was investigated in 10 days and one-month-old plants. Induction of pathogen resulted in

Poonam Gupta; Indu Ravi; Vinay Sharma

2012-01-01

172

Production of plants resistant to Alternaria carthami via organogenesis and somatic embryogenesis of safflower cv. NARI-6 treated with fungal culture filtrates  

Microsoft Academic Search

The present study describes a system for efficient plant regeneration via organogenesis and somatic embryogenesis of safflower\\u000a (Carthamus\\u000a tinctorius L.) cv. NARI-6 in fungal culture filtrates (FCF)-treated cultures. FCF was prepared by culturing Alternaria carthami fungal mycelia in selection medium for host-specific toxin production. Cotyledon explants cultured on callus induction medium\\u000a with different levels of FCF (10–50%) produced embryogenic callus.

J. Vijaya Kumar; B. D. Ranjitha Kumari; G. Sujatha; Enrique Castaño

2008-01-01

173

Involvement of hsr203J like gene homologue, protease and protease inhibitors in triggering differential defense response against Alternaria blight in Brassica  

Microsoft Academic Search

Transcript profiling of hsr203J, a known marker gene for Hypersensitive response (HR), was performed to delineate its role in differential defense against\\u000a Alternaria brassicae in tolerant and susceptible genotypes of Brassica juncea. Reverse transcriptase (RT) PCR approach was utilized to investigate the correlation between expression of hsr203J like gene(s) and pathogenesis in stage dependent manner. It was revealed that the

Arpita Mishra; Dinesh Pandey; Manoj Singh; Anil Kumar

174

Ultrastructural effects of AAL-toxin T A from the fungus Alternaria alternata on black nightshade ( Solanum nigrum L.) leaf discs and correlation with biochemical measures of toxicity  

Microsoft Academic Search

Ultrastructural effects of AAL-toxin TA from Alternaria alternata on black nightshade (Solanum nigrum L.) leaf discs and correlation with biochemical measures of toxicity. In black nightshade (Solanum nigrum L.) leaf discs floating in solutions of AAL-toxin TA (0.01–200?M) under continuous light at 25°C, electrolyte leakage, chlorophyll loss, autolysis, and photobleaching were observed within 24h. Electrolyte leakage, measured by the conductivity

H. K. Abbas; R. N. Paul; R. T. Riley; T. Tanaka; W. T. Shier

1998-01-01

175

Comparative study on the effect of chemicals on Alternaria blight in Indian mustard--a multi-location study in India.  

PubMed

High severity of Altemaria blight disease is a major constraint in production of rapeseed-mustard in India. The aim of this study was to investigate the suppressive potential of chemicals viz., zinc sulphate, borax, sulphur, potash and calcium sulphate, aqueous extracts viz., Eucalyptus globosus (50 g l-1) leaf extract and garlic (Allium sativum) bulb (20 g l-1) extract, cow urine and bio-agents Trichoderma harzianum, Pseudomonas fluorescence in comparison with the recommended chemical fungicide (mancozeb), against foliar disease Alternaria blight of Indian mustard [Brassica juncea (L.) Czern. and Coss] under five different geographical locations of India. Mancozeb recorded the lowest mean severity (leaf: 33.1%; pod: 26.3%) of Alternaria blight with efficacy of garlic bulb extract alone (leaf = 34.4%; pod = 27.3%) or in combination with cow urine (leaf = 34.2%; pod = 28.6%) being statistically at par with the recommended chemical fungicide. Chemicals also proved effective in reducing Alternaria blight severity on leaves and pods of Indian mustard (leaf = 36.3-37.9%; pod = 27.5-30.1%). The effective treatments besides providing significant reduction in disease severity also enabled increase in dry seed yield of the crop (mancozeb = 2052 kg ha-1; garlic = 2006 kg ha-1; control = 1561 kg ha-1). PMID:22167952

Meena, P D; Chattopadhyay, C; Kumar, A; Awasthi, R P; Singh, R; Kaur, S; Thomas, L; Goyal, P; Chand, P

2011-05-01

176

Original article Compatible stem taper and stem volume functions  

E-print Network

for oak performs relatively well considering the substantial number of forked oak trees. stem taper / stemOriginal article Compatible stem taper and stem volume functions for oak (Quercus robur L and Q - In this paper we develop compatible stem taper and stem volume functions for oak (Quercus robur L and Q petraea

Boyer, Edmond

177

STEM Learning Quality Indicator Map  

E-print Network

STEM Learning Quality Indicator Map Quality Indicator Initiation Involvement Implementation Innovation Student Engagement STEM learning experiences are engaging and inspire creativity and imagination STEM learning experience is activity driven with specific step by step directions STEM learning

US Army Corps of Engineers

178

Choosing a STEM Career  

NSDL National Science Digital Library

Students will view video clips about graduate and middle school students with interests in STEM careers and compare technologies from yesterday with today. They will explore careers on-line before writing about their futures as STEM professionals.

Wpsu

2009-11-10

179

STEM Club Participation and STEM Schooling Outcomes  

ERIC Educational Resources Information Center

To develop a more robust understanding of the relationship between non-formal, school-based STEM activities and students' success and persistence in STEM fields, this study evaluates how math club participation influences math GPA and how science club participation influences science GPA. Additionally, this study evaluates how math or science…

Gottfried, Michael A.; Williams, Darryl N.

2013-01-01

180

Umbilical Cord Stem Cells  

Microsoft Academic Search

The two most basic properties of stem cells are the capacities to self-renew and to differentiate into multiple cell or tissue\\u000a types (1–3). Generally, stem cells are categorized as one of three types: embryonic stem cells (ES), embryonic germ cells (EG), or adult\\u000a stem cells. ES cells are derived from the inner cell mass of the blastula (Fig. 1). They

Kathy E. Mitchell

181

Stem cell culture engineering  

Microsoft Academic Search

Stem cells have the capacity for self renewal and undergo multilineage differentiation. Stem cells isolated from both blastocysts and adult tissues represent valuable sources of cells for applications in cell therapy, drug screening and tissue engineering. While expanding stem cells in culture, it is critical to maintain their self?renewal and differentiation capacity. In generating particular cell types for specific applications,

Gargi Seth; Catherine M. Verfaillie

2005-01-01

182

Cyclic AMP-dependent protein kinase A negatively regulates conidia formation by the tangerine pathotype of Alternaria alternata.  

PubMed

The necrotrophic fungal pathogen Alternaria alternata causes brown spot diseases in many citrus cultivars. The FUS3 and SLT2 mitogen-activated protein kinases (MAPK)-mediated signaling pathways have been shown to be required for conidiation. Exogenous application of cAMP to this fungal pathogen decreased conidia formation considerably. This study determined whether a cAMP-activated protein kinase A (PKA) is required for conidiation. Using loss-of-function mutations in PKA catalytic and regulatory subunit-coding genes, we demonstrated that PKA negatively regulates conidiation. Fungal mutants lacking PKA catalytic subunit gene (PKA ( cat )) reduced growth, lacked detectable PKA activity, and produced higher amounts of conidia compared to wild-type. Introduction of a functional copy of PKA ( cat ) into a null mutant partially restored PKA activity and produced wild-type level of conidia. In contrast, fungi lacking PKA regulatory subunit gene (PKA ( reg )) produced detectable PKA activity, exhibited severe growth reduction, formed swelling hyphal segments, and produced no mature conidia. Introduction of the PKA ( reg ) gene to a regulatory subunit mutant restored all phenotypes to wild type. PKA ( reg )-null mutants induced fewer necrotic lesions on citrus compared to wild-type, whereas PKA ( cat ) mutant displayed wild-type virulence. Overall, our studies indicate that PKA and FUS3-mediated signaling pathways apparently have very different roles in the regulation of conidia production and A. alternata pathogenesis in citrus. PMID:23054702

Tsai, Hsieh-Chin; Yang, Siwy Ling; Chung, Kuang-Ren

2013-02-01

183

Resistance to oxidative stress via regulating siderophore-mediated iron acquisition by the citrus fungal pathogen Alternaria alternata.  

PubMed

The ability of the necrotrophic fungus Alternaria alternata to detoxify reactive oxygen species (ROS) is crucial for pathogenesis to citrus. We report regulation of siderophore-mediated iron acquisition and ROS resistance by the NADPH oxidase (NOX), the redox activating yes-associated protein 1 (YAP1) regulator, and the high-osmolarity glycerol 1 (HOG1) mitogen-activated protein kinase (MAPK). The A. alternata nonribosomal peptide synthetase (NPS6) is essential for the biosynthesis of siderophores, contributing to iron uptake under low-iron conditions. Fungal strains impaired for NOX, YAP1, HOG1 or NPS6 all display increased sensitivity to ROS. Exogenous addition of iron at least partially rescues ROS sensitivity seen for NPS6, YAP1, HOG1, and NOX mutants. Importantly, expression of the NPS6 gene and biosynthesis of siderophores are regulated by NOX, YAP1 and HOG1, supporting a functional link among these regulatory pathways. Although iron fully rescues H2O2 sensitivity seen in mutants impaired for the response regulator SKN7, neither expression of NPS6 nor biosynthesis of siderophores is controlled by SKN7. Our results indicate that the acquisition of environmental iron has profound effects on ROS detoxification. PMID:24586035

Chen, Li-Hung; Yang, Siwy Ling; Chung, Kuang-Ren

2014-05-01

184

Calcineurin phosphatase and phospholipase C are required for developmental and pathological functions in the citrus fungal pathogen Alternaria alternata.  

PubMed

Excessive Ca(2+) or compounds interfering with phosphoinositide cycling have been found to inhibit the growth of the tangerine pathotype of Alternaria alternata, suggesting a crucial role of Ca(2+) homeostasis in this pathotype. The roles of PLC1, a phospholipase C-coding gene and CAL1, a calcineurin phosphatase-coding gene were investigated. Targeted gene disruption showed that both PLC1 and CAL1 were required for vegetative growth, conidial formation and pathogenesis in citrus. Fungal strains lacking PLC1 or CAL1 exhibited extremely slow growth and induced small lesions on calamondin leaves. ?plc1 mutants produced fewer conidia, which germinated at slower rates than wild-type. ?cal1 mutants produced abnormal hyphae and failed to produce any mature conidia, but instead produced highly melanized bulbous hyphae with distinct septae. Fluorescence microscopy using Fluo-3 dye as a Ca(2+) indicator revealed that the ?plc1 mutant hyphae emitted stronger cytosolic fluorescence, and the ?cal1 mutant hyphae emitted less cytosolic fluorescence, than those of wild-type. Infection assessed on detached calamondin leaves revealed that application of CaCl2 or neomycin 24 h prior to inoculation provided protection against Alt. alternata. These data indicate that a dynamic equilibrium of cellular Ca(2+) is critical for developmental and pathological processes of Alt. alternata. PMID:24763426

Tsai, Hsieh-Chin; Chung, Kuang-Ren

2014-07-01

185

Functional analysis of the promoter of a glycosyl hydrolase gene induced in resistant Sinapis alba by Alternaria brassicicola.  

PubMed

A putative family 3 glycosyl hydrolase (GH) gene showed significant differential expression in resistant Sinapis alba, compared with the susceptible Brassica juncea, as part of the initial responses during interaction with the necrotroph Alternaria brassicicola. To understand the mechanism of induction, the promoter was isolated and deletion analysis carried out. All the promoter fragments were fused with the ?-glucuronidase gene and the expressions were studied in stable B. juncea transgenics and transiently transformed Nicotiana tabacum. Analysis of the expression of the promoter showed the presence of functional abscisic acid (ABA)-, jasmonic acid (JA)-, and salicylic acid (SA)-responsive cis elements. Interestingly, the promoter was found to be induced in both S. alba and B. juncea upon challenge with A. brassicicola but, in S. alba, SA had an inhibitory effect on the pathogen-induced expression of the gene whereas, in B. juncea, SA did not have any negative effect. Therefore, the SA-mediated inhibition in S. alba indicates that the induction is probably through JA or ABA signaling. The difference in the mechanism of induction of the same promoter in the resistant and susceptible plants is probably due to the differential hormonal responses initiated upon challenge with A. brassicicola. PMID:23550974

Chatterjee, Madhuvanti; Mazumder, Mrinmoy; Basu, Debabrata

2013-08-01

186

Selection and differentiation of Bacillus spp. Antagonistic to Fusarium oxysporum f.sp. lycopersici and Alternaria solani infecting Tomato.  

PubMed

Antagonistic Bacillus spp. displaying in vitro production of siderophore, chitinase, and ?-1,3-glucanase were identified from dual culture assays. In independent greenhouse studies, seed bacterization and soil application of Bacillus atrophaeus S2BC-2 challenge inoculated with Fusarium oxysporum f.sp. lycopersici (FOL) and Alternaria solani (AS) recorded low percent disease index of 25.3 and 28.7, respectively, over nonbacterised pathogen control (44.3 and 56.4). The low disease incidence corroborated with tomato growth promotion with high vigor index (8,041.2) and fresh plant weight (82.5 g) on challenge inoculation with FOL. Analysis of root and leaf samples in rhizobacterial treatment challenged with FOL and AS revealed maximum induction of chitinase (1.9 and 1.7 U/mg of protein, respectively) and ?-1,3-glucanase (23.5 and 19.2 U/mg of protein, respectively). In native gel activity assays, the rhizobacterial treatment on challenge inoculation strongly expressed three high intensity PO isoforms along with one low intensity isoform. In studies on genetic diversity of the Bacillus strains by repetitive extragenomic palindromic-polymerase chain reaction (REP-PCR) and amplified rDNA restriction analysis (ARDRA) patterns, ARDRA was more highly discriminant than REP-PCR and allowed grouping of the strains and differentiation of the antagonistic strains from other isolates. PMID:21503737

Shanmugam, Veerubommu; Atri, Kamini; Gupta, Samriti; Kanoujia, Nandina; Naruka, Digvijay Singh

2011-03-01

187

Artificial Stem Cell Niches  

PubMed Central

Stem cells are characterized by their dual ability to reproduce themselves (self-renew) and specialize (differentiate), yielding a plethora of daughter cells that maintain and regenerate tissues. In contrast to their embryonic counterparts, adult stem cells retain their unique functions only if they are in intimate contact with an instructive microenvironment, termed stem cell niche. In these niches, stem cells integrate a complex array of molecular signals that, in concert with induced cell-intrinsic regulatory networks, control their function and balance their numbers in response to physiologic demands. This progress report provides a perspective on how advanced materials technologies could be used (i) to engineer and systematically analyze specific aspects of functional stem cells niches in a controlled fashion in vitro and (ii) to target stem cell niches in vivo. Such “artificial niches” constitute potent tools for elucidating stem cell regulatory mechanisms with the capacity to directly impact the development of novel therapeutic strategies for tissue regeneration. PMID:20882496

Lutolf, Matthias P.; Blau, Helen M.

2011-01-01

188

Hematopoietic Stem Cells and Somatic Stem Cells  

Microsoft Academic Search

\\u000a Stem cells are unspecialized cells that can differentiate to generate more specialized cell types responsible for tissue-specific\\u000a function. During development, the differentiation of pluripotent embryonic stem cells leads to the production of specialized\\u000a somatic cells that are ultimately responsible for the structure and function of all adult tissues and organs. “Naturally”\\u000a pluripotent cells exist only at the earliest stages of

Kah Yong Tan; Francis S. Kim; Amy J. Wagers; Shane R. Mayack

189

Cancer stem cells - normal stem cells \\  

Microsoft Academic Search

Evidence has accumulated that cancer develops from a population of quiescent tissue committed\\/pluripotent stem cells (TCSC\\/PSC) or cells developmentally closely related to them that are distributed in various organs. To support this notio n, stem cells (SC) are long lived cells and thus may become the subject of accumulating mutations that are crucial for initiation\\/progression of cancer. More important, they

Mariusz Z. Ratajczak

2005-01-01

190

Stem Cell 101 What is a stem cell?  

E-print Network

and stem cells found in the skin generally form skin. However, some research suggests that certain adultStem Cell 101 What is a stem cell? A stem cell is a parent cell in the body that has two specific into all types of tissue in the body ­ this is called differentiation. Where are stem cells found

Minnesota, University of

191

Stem Cell Transplants  

NSDL National Science Digital Library

Transplanting embryonic stem cells from embryo into adult as a means of rejuvenating diseased cells, tissues, and organs poses ethical and moral challenges. In recent years, stem cell-derived nerve and glandular tissue has been transplanted into the brains and pancreas of Parkinson's disease and diabetes patients, respectively, with mixed results. This chapter provides background information on stem cell research, the future treatment of Parkinson's disease, and the controversy surrounding this sensitive issue.

Slesnick, Irwin

2004-01-01

192

The involvement of jasmonates and ethylene in Alternaria alternata f. sp. lycopersici toxin-induced tomato cell death  

PubMed Central

Previous studies have shown that an ethylene (ET)-dependent pathway is involved in the cell death signalling triggered by Alternaria alternata f. sp. lycopersici (AAL) toxin in detached tomato (Solanum lycopersicum) leaves. In this study, the role of jasmonic acid (JA) signalling in programmed cell death (PCD) induced by AAL toxin was analysed using a 35S::prosystemin transgenic line (35S::prosys), a JA-deficient mutant spr2, and a JA-insensitive mutant jai1. The results indicated that JA biosynthesis and signalling play a positive role in the AAL toxin-induced PCD process. In addition, treatment with the exogenous ET action inhibitor silver thiosulphate (STS) greatly suppressed necrotic lesions in 35S::prosys leaves, although 35S::prosys leaflets co-treated with AAL toxin and STS still have a significant high relative conductivity. Application of 1-aminocyclopropane-1-carboxylic acid (ACC) markedly enhanced the sensitivity of spr2 and jai1 mutants to the toxin. However, compared with AAL toxin treatment alone, exogenous application of JA to the ET-insensitive mutant Never ripe (Nr) did not alter AAL toxin-induced cell death. In addition, the reduced ET-mediated gene expression in jai1 leaves was restored by co-treatment with ACC and AAL toxin. Furthermore, JA treatment restored the decreased expression of ET biosynthetic genes but not ET-responsive genes in the Nr mutant compared with the toxin treatment alone. Based on these results, it is proposed that both JA and ET promote the AAL toxin-induced cell death alone, and the JAI1 receptor-dependent JA pathway also acts upstream of ET biosynthesis in AAL toxin-triggered PCD. PMID:21865178

Zhang, Liping; Jia, Chengguo; Liu, Lihong; Zhang, Zhiming; Li, Chuanyou; Wang, Qiaomei

2011-01-01

193

Biopriming of Infected Carrot Seed with an Antagonist, Clonostachys rosea, Selected for Control of Seedborne Alternaria spp.  

PubMed

ABSTRACT An ecological approach was used to select fungal antagonists effective against the seedborne pathogens Alternaria dauci and A. radicina on carrot. Twenty-five and 105 isolates originating from cereal and carrot habitats were screened against the pathogens in planta, respectively. Irrespective of isolate origin, fungal isolates belonging to Clonostachys rosea controlled pre- and postemergence death caused by A. dauci and A. radicina as effectively as the fungicide iprodione. Isolate IK726 of C. rosea was used in biopriming a seed lot with 29% A. radicina and 11% A. dauci (highly infected), and a seed lot with 4% A. radicina and 7% A. dauci (low infection). Seeds were primed with water alone (hydropriming) or with addition of C. rosea IK726 (biopriming). The occurrence of A. radicina and A. dauci increased twofold and fivefold, respectively, during 14 days hydropriming, irrespective of the initial infection level. On highly infected seed, biopriming reduced the incidence of A. radicina to <2.3% and that of A. dauci to <4.8% while the level of both pathogens was <0.5% on bioprimed seed with a low initial infection rate. In sand stand establishment tests, hydroprimed seeds had a lower healthy seedling stand than nonprimed seeds, mainly due to a high degree of postemergence seedling death. In contrast, biopriming resulted in a seedling stand that was better than that of both nonprimed and hydroprimed seeds. C. rosea IK726 multiplied fivefold to eightfold, and microscopic observations using C. rosea IK726 transformed with a green fluorescent protein (GFP) reporter gene showed that seeds were covered with a fine web of sporulating mycelium of C. rosea. The positive effect of biopriming on healthy seedling stand remained after 5 months of storage at 4 degrees C and IK726 survived at high numbers on these seed. In this study, we demonstrated that bio-priming with the biocontrol strain C. rosea IK726 facilitates priming of infected seeds without risking adverse effects on seedling establishment. PMID:18943479

Jensen, Birgit; Knudsen, Inge M B; Madsen, Mette; Jensen, Dan Funck

2004-06-01

194

RNA-Seq derived identification of differential transcription in the chrysanthemum leaf following inoculation with Alternaria tenuissima  

PubMed Central

Background A major production constraint on the important ornamental species chrysanthemum is black spot which is caused by the necrotrophic fungus Alternaria tenuissima. The molecular basis of host resistance to A. tenuissima has not been studied as yet in any detail. Here, high throughput sequencing was taken to characterize the transcriptomic response of the chrysanthemum leaf to A. tenuissima inoculation. Results The transcriptomic data was acquired using RNA-Seq technology, based on the Illumina HiSeq™ 2000 platform. Four different libraries derived from two sets of leaves harvested from either inoculated or mock-inoculated plants were characterized. Over seven million clean reads were generated from each library, each corresponding to a coverage of >350,000 nt. About 70% of the reads could be mapped to a set of chrysanthemum unigenes. Read frequency was used as a measure of transcript abundance and therefore as an identifier of differential transcription in the four libraries. The differentially transcribed genes identified were involved in photosynthesis, pathogen recognition, reactive oxygen species generation, cell wall modification and phytohormone signalling; in addition, a number of varied transcription factors were identified. A selection of 23 of the genes was transcription-profiled using quantitative RT-PCR to validate the RNA-Seq output. Conclusions A substantial body of chrysanthemum transcriptomic sequence was generated, which led to a number of insights into the molecular basis of the host response to A. tenuissima infection. Although most of the differentially transcribed genes were up-regulated by the presence of the pathogen, those involved in photosynthesis were down-regulated. PMID:24387266

2014-01-01

195

Stem Cell Resources  

NSDL National Science Digital Library

The mission of the Stem Cell Resources website is "to provide timely, reliable, high-quality and scientifically credible stem cell information for the educational community worldwide." The website is a division of Bioscience Network which publishes online science education materials. On the site, visitors will find a stem cell image library, a multimedia area, and a special section titled "For Educators". In the "For Educators" area, visitors will find links to a primer on stem cells and links to educational resources on stem cells from curriculum to case studies to lesson plans from such trusted sources as the Australian Stem Cell Centre and the National Institutes of Health. Moving on, the "Multimedia" area includes videos that show how embryonic stem cell lines are made, along with other animations and graphics on the topic. Additionally, the site's "SCR Library" area includes the link to the Stem Cell Image Library, which provides dozens of photos of stem cells taken from researchers at the University of Cambridge and other institutions.

196

Stem cells and reproduction  

PubMed Central

Purpose of review To review the latest developments in reproductive tract stem cell biology. Recent findings In 2004, two studies indicated that ovaries contain stem cells which form oocytes in adults and that can be cultured in vitro into mature oocytes. A live birth after orthotopic transplantation of cyropreserved ovarian tissue in a woman whose ovaries were damaged by chemotherapy demonstrates the clinical potential of these cells. In the same year, another study provided novel evidence of endometrial regeneration by stem cells in women who received bone marrow transplants. This finding has potential for the use in treatment of uterine disorders. It also supports a new theory for the cause of endometriosis, which may have its origin in ectopic transdifferentiation of stem cells. Several recent studies have demonstrated that fetal cells enter the maternal circulation and generate microchimerism in the mother. The uterus is a dynamic organ permeable to fetal stem cells, capable of transdifferentiation and an end organ in which bone marrow stem cells may differentiate. Finally stem cell transformation can be an underlying cause of ovarian cancer. Summary Whereas we are just beginning to understand stem cells, the potential implications of stem cells to reproductive biology and medicine are apparent. PMID:20305558

Du, Hongling; Taylor, Hugh S.

2011-01-01

197

Stable integration and expression of wasabi defensin gene in "Egusi" melon (Colocynthis citrullus L.) confers resistance to Fusarium wilt and Alternaria leaf spot.  

PubMed

Production of "Egusi" melon (Colocynthis citrullus L.) in West Africa is limited by fungal diseases, such as Alternaria leaf spot and Fusarium wilt. In order to engineer "Egusi" resistant to these diseases, cotyledonary explants of two "Egusi" genotypes, 'Ejagham' and NHC1-130, were transformed with Agrobacterium tumefaciens strain EHA101 harbouring wasabi defensin gene (isolated from Wasabia japonica L.) in a binary vector pEKH1. After co-cultivation for 3 days, infected explants were transferred to MS medium containing 100 mg l(-l) kanamycin to select transformed tissues. After 3 weeks of culture, adventitious shoots appeared directly along the edges of the explants. As much as 19 out of 52 (36.5%) and 25 out of 71 (35.2%) of the explants in genotype NHC1-130 and 'Ejagham', respectively, formed shoots after 6 weeks of culture. As much as 74% (14 out of 19) of the shoots regenerated in genotype NHC1-130 and 72% (18 out of 25) of those produced in genotype 'Ejagham' were transgenic. A DNA fragment corresponding to the wasabi defensin gene or the selection marker nptII was amplified by PCR from the genomic DNA of all regenerated plant clones rooted on hormone-free MS medium under the same selection pressure, suggesting their transgenic nature. Southern blot analysis confirmed successful integration of 1-5 copies of the transgene. RT-PCR, northern and western blot analyses revealed that wasabi defensin gene was expressed in transgenic lines. Transgenic lines showed increased levels of resistance to Alternaria solani, which causes Alternaria leaf spot and Fusarium oxysporum, which causes Fusarium wilt, as compared to that of untransformed plants. PMID:20552202

Ntui, Valentine Otang; Thirukkumaran, Gunaratnam; Azadi, Pejman; Khan, Raham Sher; Nakamura, Ikuo; Mii, Masahiro

2010-09-01

198

Stemming vision loss with stem cells  

PubMed Central

Dramatic advances in the field of stem cell research have raised the possibility of using these cells to treat a variety of diseases. The eye is an excellent target organ for such cell-based therapeutics due to its ready accessibility, the prevalence of vasculo- and neurodegenerative diseases affecting vision, and the availability of animal models to demonstrate proof of concept. In fact, stem cell therapies have already been applied to the treatment of disease affecting the ocular surface, leading to preservation of vision. Diseases in the back of the eye, such as macular degeneration, diabetic retinopathy, and inherited retinal degenerations, present greater challenges, but rapidly emerging stem cell technologies hold the promise of autologous grafts to stabilize vision loss through cellular replacement or paracrine rescue effects. PMID:20811157

Marchetti, Valentina; Krohne, Tim U.; Friedlander, David F.; Friedlander, Martin

2010-01-01

199

Stem cells in dermatology*  

PubMed Central

Preclinical and clinical research have shown that stem cell therapy could be a promising therapeutic option for many diseases in which current medical treatments do not achieve satisfying results or cure. This article describes stem cells sources and their therapeutic applications in dermatology today. PMID:24770506

Ogliari, Karolyn Sassi; Marinowic, Daniel; Brum, Dario Eduardo; Loth, Fabrizio

2014-01-01

200

Skeletal muscle stem cells  

Microsoft Academic Search

Satellite cells are myogenic stem cells responsible for the post-natal growth, repair and maintenance of skeletal muscle. This review focuses on the basic biology of the satellite cell with emphasis on its role in muscle repair and parallels between embryonic myogenesis and muscle regeneration. Recent advances have altered the long-standing view of the satellite cell as a committed myogenic stem

Jennifer CJ Chen; David J Goldhamer

2003-01-01

201

Bioreactors Stem Cells  

E-print Network

Keywords Bioreactors Stem Cells Regenerative Medicine Tissue Engineering Pharmacology » Prof. M.; yeZhelyev, M.; eMMrich, F.; o'regan, r.; bader, a. Quantum dots for human mesenchymal stem cells and mechanical forces mediated to the cells by the matrix. The in vivo extracellular matrix constitutes

Schüler, Axel

202

Lock For Valve Stem  

NASA Technical Reports Server (NTRS)

Simple, cheap device locks valve stem so its setting cannot be changed by unauthorized people. Device covers valve stem; cover locked in place with standard padlock. Valve lock made of PVC pipe and packing band. Shears, drill or punch, and forming rod only tools needed.

Burley, Richard K.; Guirguis, Kamal S.

1991-01-01

203

STEM Careers Ambassadors  

ERIC Educational Resources Information Center

This article is designed to help teachers feel more confident in their work with STEM Ambassadors to further enhance enrichment activities. Skills shortages in Science, Technology, Engineering, Maths (STEM) and the Built Environment are well documented, and will continue to be an issue whether people are in a period of recession or recovery. The…

Eaton, Denise

2011-01-01

204

TPCP: Cryphonectria canker of Eucalyptus CRYPHONECTRIA CANKER OF  

E-print Network

of the fungus can easily be seen using a simple hand lens.. These trees often die as competition in BIOLOGY such as Zululand, and warmer parts of the Eastern and Northern Transvaal. Death of young coppice. clones

205

I-STEM  

NSDL National Science Digital Library

The University of Illinois at Urbana-Champaign has developed a multi-pronged approach to remedying the lack of academic emphasis on the STEM subjects, from preschool through college, as well as the lack of interest in STEM subjects on the part of youth in the United States. Visitors can read about the University's four goals under the "Goals" tab at the top of any page. The "STEM Ed Projects" tab contains a directory of externally funded projects divided into four categories, and which are then further divided into subcategories. Visitors will find such projects as "Improving Supply and Demand Data for the Preparation of Secondary Science and Math Teachers" and "Clean Energy Education Workshop", under the category that aims to shape policy and advocate for STEM education. The "Resources" tab contains half a dozen categories under which visitors will find Outreach Resources, Teacher Development and Resources, and Policy and Advocacy for STEM Ed.

206

Intraoperative Stem Cell Therapy  

PubMed Central

Stem cells hold significant promise for regeneration of tissue defects and disease-modifying therapies. Although numerous promising stem cell approaches are advancing in clinical trials, intraoperative stem cell therapies offer more immediate hope by integrating an autologous cell source with a well-established surgical intervention in a single procedure. Herein, the major developments in intraoperative stem cell approaches, from in vivo models to clinical studies, are reviewed, and the potential regenerative mechanisms and the roles of different cell populations in the regeneration process are discussed. Although intraoperative stem cell therapies have been shown to be safe and effective for several indications, there are still critical challenges to be tackled prior to adoption into the standard surgical armamentarium. PMID:22809140

Coelho, Monica Beato; Cabral, Joaquim M.S.; Karp, Jeffrey M.

2013-01-01

207

Hematopoietic stem cell transplantation  

PubMed Central

More than 25,000 hematopoietic stem cell transplantations (HSCTs) are performed each year for the treatment of lymphoma, leukemia, immune-deficiency illnesses, congenital metabolic defects, hemoglobinopathies, and myelodysplastic and myeloproliferative syndromes. Before transplantation, patients receive intensive myeloablative chemoradiotherapy followed by stem cell “rescue.” Autologous HSCT is performed using the patient’s own hematopoietic stem cells, which are harvested before transplantation and reinfused after myeloablation. Allogeneic HSCT uses human leukocyte antigen (HLA)-matched stem cells derived from a donor. Survival after allogeneic transplantation depends on donor–recipient matching, the graft-versus-host response, and the development of a graft versus leukemia effect. This article reviews the biology of stem cells, clinical efficacy of HSCT, transplantation procedures, and potential complications. PMID:24198516

Hatzimichael, Eleftheria; Tuthill, Mark

2010-01-01

208

"Mesenchymal" stem cells.  

PubMed

Two opposing descriptions of so-called mesenchymal stem cells (MSCs) exist at this time. One sees MSCs as the postnatal, self-renewing, and multipotent stem cells for the skeleton. This cell coincides with a specific type of bone marrow perivascular cell. In skeletal physiology, this skeletal stem cell is pivotal to the growth and lifelong turnover of bone and to its native regeneration capacity. In hematopoietic physiology, its role as a key player in maintaining hematopoietic stem cells in their niche and in regulating the hematopoietic microenvironment is emerging. In the alternative description, MSCs are ubiquitous in connective tissues and are defined by in vitro characteristics and by their use in therapy, which rests on their ability to modulate the function of host tissues rather than on stem cell properties. Here, I discuss how the two views developed, conceptually and experimentally, and attempt to clarify the confusion arising from their collision. PMID:25150008

Bianco, Paolo

2014-10-11

209

Spontaneous loss of a conditionally dispensable chromosome from the Alternaria alternata apple pathotype leads to loss of toxin production and pathogenicity.  

PubMed

The Alternaria alternata apple pathotype causes Alternaria blotch of susceptible apple cultivars through the production of a cyclic peptide, host-specific toxin, AM-toxin. We recently cloned a cyclic peptide synthetase gene, AMT, whose product catalyzes the production of AM-toxin and showed that it resides on chromosomes of 1.8 Mb or less, depending on the A. alternata apple pathotype strain. Reverse transcriptase (RT)-PCR, using primers specific to AMT, on laboratory sub-cultured strains previously shown to produce AM-toxin, identified one isolate that did not express the gene. A leaf necrosis bioassay confirmed an AM-toxin-minus phenotype. However, an original isolate of this strain which had not undergone sub-culture gave a positive result by both RTPCR and bioassay. Contour-clamped homogeneous electric field electrophoresis and Southern hybridization demonstrated the loss of a 1.1-Mb chromosome in the non-toxin-producing isolate. Since this chromosome can be entirely lost without affecting growth, but is necessary for pathogenicity, we propose it is a conditionally dispensable chromosome. PMID:11570518

Johnson, L J; Johnson, R D; Akamatsu, H; Salamiah, A; Otani, H; Kohmoto, K; Kodama, M

2001-08-01

210

``Stemness'': Transcriptional Profiling of Embryonic and Adult Stem Cells  

Microsoft Academic Search

The transcriptional profiles of mouse embryonic, neural, and hematopoietic stem cells were compared to define a genetic program for stem cells. A total of 216 genes are enriched in all three types of stem cells, and several of these genes are clustered in the genome. When compared to differentiated cell types, stem cells express a significantly higher number of genes

Miguel Ramalho-Santos; Soonsang Yoon; Yumi Matsuzaki; Richard C. Mulligan; Douglas A. Melton

2002-01-01

211

Cell Stem Cell Stem Cell Epigenetics: Looking Forward  

E-print Network

Cell Stem Cell Voices Stem Cell Epigenetics: Looking Forward Epigenetics in Adult SCs The integrity of tissues is maintained by adult stem cells during adulthood. How- ever, recent work indicates that tissues often contain more than one population of stem cells that are located at distinct niches and display

Sander, Maike

212

Cell Stem Cell Control of Stem Cell Fate by Physical  

E-print Network

, Philadelphia, PA 19104, USA 5Stem Cell Laboratory, Pennington Biomedical Research Center, Louisiana StateCell Stem Cell Review Control of Stem Cell Fate by Physical Interactions with the Extracellular.06.016 A diverse array of environmental factors contributes to the overall control of stem cell activity

Chen, Christopher S.

213

Autophagy in stem cells  

PubMed Central

Autophagy is a highly conserved cellular process by which cytoplasmic components are sequestered in autophagosomes and delivered to lysosomes for degradation. As a major intracellular degradation and recycling pathway, autophagy is crucial for maintaining cellular homeostasis as well as remodeling during normal development, and dysfunctions in autophagy have been associated with a variety of pathologies including cancer, inflammatory bowel disease and neurodegenerative disease. Stem cells are unique in their ability to self-renew and differentiate into various cells in the body, which are important in development, tissue renewal and a range of disease processes. Therefore, it is predicted that autophagy would be crucial for the quality control mechanisms and maintenance of cellular homeostasis in various stem cells given their relatively long life in the organisms. In contrast to the extensive body of knowledge available for somatic cells, the role of autophagy in the maintenance and function of stem cells is only beginning to be revealed as a result of recent studies. Here we provide a comprehensive review of the current understanding of the mechanisms and regulation of autophagy in embryonic stem cells, several tissue stem cells (particularly hematopoietic stem cells), as well as a number of cancer stem cells. We discuss how recent studies of different knockout mice models have defined the roles of various autophagy genes and related pathways in the regulation of the maintenance, expansion and differentiation of various stem cells. We also highlight the many unanswered questions that will help to drive further research at the intersection of autophagy and stem cell biology in the near future. PMID:23486312

Guan, Jun-Lin; Simon, Anna Katharina; Prescott, Mark; Menendez, Javier A.; Liu, Fei; Wang, Fen; Wang, Chenran; Wolvetang, Ernst; Vazquez-Martin, Alejandro; Zhang, Jue

2013-01-01

214

Stem Cell Task Force  

NSDL National Science Digital Library

This Web site from the National Institutes of Health (NIH) provides an overview of the activities of an NIH task force established to move the stem cell research agenda forward. The section titled Scientific Research may be of particular interest to researchers in this area. It provides links to the Web sites of stem cell-related research at a number of NIH institutes, as well as an extensive information index, a FAQs page about stem cell research, information on funding opportunities, and much more.

215

Information on Stem Cell Research  

MedlinePLUS

Information on Stem Cell Research Research @ NINDS Stem Cell Highlights Submit a hESC line for NIH review (9/21/09) NIH Opens Website ... here: Human Induced Pluripotent Stem Cells NINDS Stem Cell Research on Campus The Intramural Research Program of ...

216

LESSON PLAN Stem Cell Discussion  

E-print Network

of stem cell research · research the current research situation · debate the future of stem cell of the ethical, moral and social implications of stem cell research. Photocopy these pages and distribute to students to read. · Make a list of advantages and disadvantages of using embryonic stem cells in research

Rambaut, Andrew

217

Stem cells and brain cancer  

Microsoft Academic Search

An increasing body of research is showing that cancers might contain their own stem cells. In fact, cancer cells, like stem cells, can proliferate indefinitely through a deregulated cellular self-renewal capacity. This raises the possibility that some features of tumor cells may be due to cancer stem cells. Stem cell-like cancer cells were isolated from several solid tumors. Now, evidence

U Galderisi; M Cipollaro; A Giordano

2006-01-01

218

Haute Culture: Tailoring stem cells  

E-print Network

Biology, Department of Stem Cell and Regenerative Biology, Harvard University Massachusetts General Hospital Fernando Camargo, PhD Assistant Professor of Stem Cell Regenerative Biology, Department of Stem Cell and Regenerative Biology, Harvard University Children's Hospital Boston Stem Cell Program #12

Chou, James

219

Cell Stem Cell Clinical Progress  

E-print Network

Cell Stem Cell Clinical Progress Rapid Expansion of Human Hematopoietic Stem Cells by Automated implementations of hematopoietic stem cells (HSCs) and their deriva- tives further increase interest in strategies the marked improvements that control of feed- back signaling can offer primary stem cell culture

Zandstra, Peter W.

220

Springboard to STEM  

NSDL National Science Digital Library

The goal of the Springboard to STEM program is "to increase student interest in science, technology, engineering and mathematics (STEM) and provide training and classroom materials for teachers." On this website, visitors can take advantage of free educational materials like worksheets, lesson plans, and discussion questions. Visitors need to fill out a form on the site before they can access all of the materials, but this only takes a minute or two. Moving on, the News and Links area contains links to their work around STEM education and the project's Twitter feed. The Marketplace is another great feature of the site which contains links to high quality STEM-related resources, such as books and classroom DVDs, that are available for purchase.

221

Springboard to STEM  

NSDL National Science Digital Library

The goal of the Springboard to STEM program is "to increase student interest in science, technology, engineering and mathematics (STEM) and provide training and classroom materials for teachers." On this website, visitors can take advantage of free educational materials like worksheets, lesson plans, and discussion questions. Visitors need to fill out a form on the site before they can access all of the materials, but this only takes a minute or two. Moving on, the News and Links area contains links to their work around STEM education and the project's Twitter feed. The Marketplace is another great feature of the site which contains links to high quality STEM-related resources, such as books and classroom DVDs, that are available for purchase.

2013-11-26

222

STEM Careers Grad Students  

NSDL National Science Digital Library

This brief video from WPSU introduces a diverse group of graduate students with interests in STEM careers. From deep sea diving to creating video games, each graduate student is pursuing activities beyond the stereotypical view of a nerdy scientist.

Wpsu

2009-11-10

223

The advantages of hair follicle pluripotent stem cells over embryonic stem cells and induced pluripotent stem cells for regenerative medicine  

Microsoft Academic Search

Multipotent adult stem cells have many potential therapeutic applications. Our recent findings suggest that hair follicles are a promising source of easily accessible multipotent stem cells. Stem cells in the hair follicle area express the neural stem cell marker nestin, suggesting that hair-follicle stem cells and neural stem cells have common features. Nestin-expressing hair follicle stem cells can form neurons

Yasuyuki Amoh; Kensei Katsuoka; Robert M. Hoffman

2010-01-01

224

The Neural Stem Cells  

Microsoft Academic Search

\\u000a Neural stem cells represent a heterogeneous population of mitotically active, self-renewing and multipotent cells of both\\u000a the developing and the adult central nervous system (CNS) showing complex patterns of gene expression that may vary in both\\u000a space and time. Endogenous stem cells residing within CNS germinal niches might concur to nervous system repair owing to their\\u000a ability to drive neurogenesis

Stefano Pluchino; Marco Bacigaluppi; Elena Brini; Erica Butti; Chiara Cossetti; Melania Cusimano; Lucia Zanotti; Gianvito Martino

225

Stem CAM in arborescent succulents  

Microsoft Academic Search

Stem CAM with a peripheral chlorenchyma in stem succulents growing up to arborescent sizes and life forms appears to be a\\u000a unique evolution as it requires delayed and reduced bark formation and stem stomata. However, stem succulence as a convergent\\u000a morphotype and with it the stem CAM physiotype evolved polyphyletically in many divergent taxa of the dicotyledonous angiosperms.\\u000a Controlling water

U. Lüttge

2008-01-01

226

Clonal interrogation of stem cells  

Microsoft Academic Search

Individual stem cells are functionally defined by their self-renewal and differentiation potential. Methods for clonal analysis are essential for understanding stem cells, particularly given the increasing evidence for stem-cell heterogeneity. Stem cells reside within complex microenvironments, making single-cell analysis particularly challenging. Furthermore, simultaneous molecular and functional characterization of single stem cells is not trivial. Here we explore clonal assays applied

Kristin Hope; Mickie Bhatia

2011-01-01

227

The Stemness Phenotype Model  

PubMed Central

The identification of a fraction of cancer stem cells (CSCs) associated with resistance to chemotherapy in most solid tumors leads to the dogma that eliminating this fraction will cure cancer. Experimental data has challenged this simplistic and optimistic model. Opposite to the classical cancer stem cell model, we introduced the stemness phenotype model (SPM), which proposed that all glioma cells possess stem cell properties and that the stemness is modulated by the microenvironment. A key prediction of the SPM is that to cure gliomas all gliomas cells (CSCs and non-CSCs) should be eliminated at once. Other theories closely resembling the SPM and its predictions have recently been proposed, suggesting that the SPM may be a useful model for other type of tumors. Here, we review data from other tumors that strongly support the concepts of the SPM applied to gliomas. We include data related to: (1) the presence of a rare but constant fraction of CSCs in established cancer cell lines, (2) the clonal origin of cancer, (3) the symmetrical division, (4) the ability of “non-CSCs” to generate “CSCs,” and (5) the effect of the microenvironment on cancer stemness. The aforenamed issues that decisively supported the SPM proposed for gliomas can also be applied to breast, lung, prostate cancer, and melanoma and perhaps other tumors in general. If the glioma SPM is correct and can be extrapolated to other types of cancer, it will have profound implications in the development of novel modalities for cancer treatment. PMID:22928120

Cruz, M. H.; Siden, A.; Calaf, G. M.; Delwar, Z. M.; Yakisich, J. S.

2012-01-01

228

Control of Stemness by Fibroblast Growth Factor Signaling in Stem Cells and Cancer Stem Cells  

Microsoft Academic Search

Since the discovery of stem cells, scientists have invested tremendous effort in establishing in vitro culture conditions in order to maintain the self-renewal and efficient proliferative capabilities of stem cells by manipulating a va- riety of growth factors. Fibroblast growth factor (FGF) is one of the most common growth factors used to expand stem cells, including human embryonic stem (hES)

Noriko Gotoh

2009-01-01

229

Molecular characterization and detection of mutations associated with resistance to succinate dehydrogenase-inhibiting fungicides in Alternaria solani.  

PubMed

Early blight, caused by Alternaria solani, is an economically important foliar disease of potato in several production areas of the United States. Few potato cultivars possess resistance to early blight; therefore, the application of fungicides is the primary means of achieving disease control. Previous work in our laboratory reported resistance to the succinate dehydrogenase-inhibiting (SDHI) fungicide boscalid in this plant pathogen with a concomitant loss of disease control. Two phenotypes were detected, one in which A. solani isolates were moderately resistant to boscalid, the other in which isolates were highly resistant to the fungicide. Resistance in other fungal plant pathogens to SDHI fungicides is known to occur due to amino acid exchanges in the soluble subunit succinate dehydrogenase B (SdhB), C (SdhC), and D (SdhD) proteins. In this study, the AsSdhB, AsSdhC, and AsSdhD genes were analyzed and compared in sensitive (50% effective concentration [EC50] < 5 ?g ml(-1)), moderately resistant (EC50 = 5.1 to 20 ?g ml(-1)), highly resistant (EC50 = 20.1 to 100 ?g ml(-1)), and very highly resistant (EC50 > 100 ?g ml(-1)) A. solani isolates. In total, five mutations were detected, two in each of the AsSdhB and AsSdhD genes and one in the AsSdhC gene. The sequencing of AsSdhB elucidated point mutations cytosine (C) to thymine (T) at nucleotide 990 and adenine (A) to guanine (G) at nucleotide 991, leading to an exchange from histidine to tyrosine (H278Y) or arginine (H278R), respectively, at codon 278. The H278R exchange was detected in 4 of 10 A. solani isolates moderately resistant to boscalid, exhibiting EC50 values of 6 to 8 ?g ml(-1). Further genetic analysis also confirmed this mutation in isolates with high and very high EC50 values for boscalid of 28 to 500 ?g ml(-1). Subsequent sequencing of AsSdhC and AsSdhD genes confirmed the presence of additional mutations from A to G at nucleotide position 490 in AsSdhC and at nucleotide position 398 in the AsSdhD, conferring H134R and H133R exchanges in AsSdhC and AsSdhD, respectively. The H134R exchange in AsSdhC was observed in A. solani isolates with sensitive, moderate, highly resistant, and very highly resistant boscalid phenotypes, and the AsSdhD H133R exchange was observed in isolates with both moderate and very high EC50 value boscalid phenotypes. Detection and differentiation of point mutations in AsSdhB resulting in H278R and H278Y exchanges in the AsSdhB subunit were facilitated by the development of a mismatch amplification mutation assay. Detection of these two mutations in boscalid-resistant isolates, in addition to mutations in AsSdhC and AsSdhD resulting in an H134R and H133R exchange, respectively, was achieved by the development of a multiplex polymerase chain reaction to detect and differentiate the sensitive and resistant isolates based on the single-nucleotide polymorphisms present in all three genes. A single A. solani isolate with resistance to boscalid did not contain any of the above-mentioned exchanges but did contain a substitution of aspartate to glutamic acid at amino acid position 123 (D123E) in the AsSdhD subunit. Among A. solani isolates possessing resistance to boscalid, point mutations in AsSdhB were more frequently detected than mutations in genes coding for any other subunit. PMID:23901829

Mallik, I; Arabiat, S; Pasche, J S; Bolton, M D; Patel, J S; Gudmestad, N C

2014-01-01

230

Multiple Epoxide Hydrolases in Alternaria alternata f. sp. lycopersici and Their Relationship to Medium Composition and Host-Specific Toxin Production  

PubMed Central

The production of Alternaria alternata f. sp. lycopersici host-specific toxins (AAL toxins) and epoxide hydrolase (EH) activity were studied during the growth of this plant-pathogenic fungus in stationary liquid cultures. Media containing pectin as the primary carbon source displayed peaks of EH activity at day 4 and at day 12. When pectin was replaced by glucose, there was a single peak of EH activity at day 6. Partial characterization of the EH activities suggests the presence of three biochemically distinguishable EH activities. Two of them have a molecular mass of 25 kDa and a pI of 4.9, while the other has a molecular mass of 20 kDa and a pI of 4.7. Each of the EH activities can be distinguished by substrate preference and sensitivity to inhibitors. The EH activities present at day 6 (glucose) or day 12 (pectin) are concomitant with AAL toxin production. PMID:10347018

Morisseau, Christophe; Ward, Barney L.; Gilchrist, David G.; Hammock, Bruce D.

1999-01-01

231

Cloning and characterization of a cyclic peptide synthetase gene from Alternaria alternata apple pathotype whose product is involved in AM-toxin synthesis and pathogenicity.  

PubMed

Afternaria afternata apple pathotype causes Alternaria blotch of susceptible apple cultivars through the production of a cyclic peptide host-specific toxin, AM-toxin. PCR (polymerase chain reaction), with primers designed to conserved domains of peptide synthetase genes, amplified several products from A. alternata apple pathotype that showed high similarity to other fungal peptide synthetases and were specific to the apple pathotype. Screening of a Lambda Zap genomic library with these PCR-generated probes identified overlapping clones containing a complete cyclic peptide synthetase gene of 13.1 kb in length with no introns. Disruption of this gene, designated AM-toxin synthetase (AMT), by transformation of wild-type A. afternata apple pathotype with disruption vectors resulted in toxin-minus mutants, which were also unable to cause disease symptoms on susceptible apple cultivars. AM-toxin synthetase is therefore a primary determinant of virulence and specificity in the A. alternata apple pathotype/apple interaction. PMID:10875335

Johnson, R D; Johnson, L; Itoh, Y; Kodama, M; Otani, H; Kohmoto, K

2000-07-01

232

6. VIEW SHOWING INCLINED OUTLET GATE WHEEL, STEM AND STEM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. VIEW SHOWING INCLINED OUTLET GATE WHEEL, STEM AND STEM GUIDE (18' HARDESTY GATE), LOOKING SOUTHEAST - High Mountain Dams in Bonneville Unit, Long Lake Dam, Wasatch National Forest, Kamas, Summit County, UT

233

7. VIEW OF INCLINED OUTLET GATE WHEEL, STEM AND STEM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. VIEW OF INCLINED OUTLET GATE WHEEL, STEM AND STEM GUIDE (15' HARDESTY MODEL 115 GATE), LOOKING NORTHWEST - High Mountain Dams in Bonneville Unit, Marjorie Lake Dam, Wasatch National Forest, Kamas, Summit County, UT

234

5. VIEW OF UPRIGHT OUTLET GATE WHEEL, STEM AND STEM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW OF UPRIGHT OUTLET GATE WHEEL, STEM AND STEM GUIDE (HARDESTY CAST IRON RECTANGULAR SLIDE GATE), LOOKING SOUTHWEST - High Mountain Dams in Bonneville Unit, Lost Lake Dam, Kamas, Summit County, UT

235

5. VIEW SHOWING INCLINED OUTLET GATE WHEEL, STEM AND STEM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW SHOWING INCLINED OUTLET GATE WHEEL, STEM AND STEM GUIDE (28' WIDE HARDESTY CAST IRON SLIDE HEADGATE), LOOKING NORTHEAST - High Mountain Dams in Bonneville Unit, Duck Lake Dam, Wasatch National Forest, Kamas, Summit County, UT

236

5. VIEW OF UPRIGHT OUTLET GATE WHEEL, STEM AND STEM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW OF UPRIGHT OUTLET GATE WHEEL, STEM AND STEM GUIDE, LOOKING NORTHWEST - High Mountain Dams in Upalco Unit, Drift Lake Dam, Ashley National Forest, 11.4 miles Northwest of Swift Creek Campground, Mountain Home, Duchesne County, UT

237

5. VIEW OF INCLINED OUTLET GATE WHEEL, STEM AND STEM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW OF INCLINED OUTLET GATE WHEEL, STEM AND STEM GUIDE, (12' DIAMETER HARDESTY MODEL 112 CIRCULAR GATE), LOOKING NORTHEAST - High Mountain Dams in Bonneville Unit, Island Lake Dam, Wasatch National Forest, Kamas, Summit County, UT

238

4. VIEW OF INCLINED OUTLET GATE, STEM, STEM GUIDE AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. VIEW OF INCLINED OUTLET GATE, STEM, STEM GUIDE AND WHEEL (10' HARDESTY VERTICAL LIFT GATE), LOOKING NORTHWEST - High Mountain Dams in Bonneville Unit, Pot Lake Dam, Wasatch National Forest, Kamas, Summit County, UT

239

5. VIEW OF UPRIGHT OUTLET GATE, STEM, STEM GUIDE AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW OF UPRIGHT OUTLET GATE, STEM, STEM GUIDE AND WHEEL (10' HARDESTY CAST IRON VERTICAL LIFT GATE), LOOKING WEST - High Mountain Dams in Bonneville Unit, Weir Lake Dam, Wasatch National Forest, Kamas, Summit County, UT

240

7. VIEW OF UPRIGHT OUTLET GATE, WHEEL STEM AND STEM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. VIEW OF UPRIGHT OUTLET GATE, WHEEL STEM AND STEM GUIDE (14' DIAMETER CIRCULAR CALCO CAST IRON SLIDE GATE), LOOKING SOUTHEAST - High Mountain Dams in Bonneville Unit, Fire Lake Dam, Wasatch National Forest, Kamas, Summit County, UT

241

Pathways to Science: STEM  

NSDL National Science Digital Library

Sponsored by NASA and the National Science Foundation, the Pathways to Science Project was created by the Institute for Broadening Participation to support "pathways to the STEM fields: science, technology, engineering, and mathematics." The project works on connecting underrepresented groups with STEM programs, funding, mentoring, and resources. The "Students" area features a sign-in area where students can sign up to receive targeted emails that will inform them of new STEM-focused scholarship and mentoring opportunities. The "Programs" area features a database of over 1500 programs designed for K-8 students, college educators, and undergraduate students. Additionally, the site also includes a "News" area where users can learn about recent success stories from universities around the United States, along with the particulars of upcoming conferences and seminars.

242

Germline Stem Cells  

PubMed Central

Sperm and egg production requires a robust stem cell system that balances self-renewal with differentiation. Self-renewal at the expense of differentiation can cause tumorigenesis, whereas differentiation at the expense of self-renewal can cause germ cell depletion and infertility. In most organisms, and sometimes in both sexes, germline stem cells (GSCs) often reside in a defined anatomical niche. Factors within the niche regulate a balance between GSC self-renewal and differentiation. Asymmetric division of the germline stem cell to form daughter cells with alternative fates is common. The exception to both these tendencies is the mammalian testis where there does not appear to be an obvious anatomical niche and where GSC homeostasis is likely accomplished by a stochastic balance of self-renewal and differentiation and not by regulated asymmetric cell division. Despite these apparent differences, GSCs in all organisms share many common mechanisms, although not necessarily molecules, to guarantee survival of the germline. PMID:21791699

Spradling, Allan; Fuller, Margaret T.; Braun, Robert E.; Yoshida, Shosei

2011-01-01

243

Skeletal muscle stem cells  

PubMed Central

Satellite cells are myogenic stem cells responsible for the post-natal growth, repair and maintenance of skeletal muscle. This review focuses on the basic biology of the satellite cell with emphasis on its role in muscle repair and parallels between embryonic myogenesis and muscle regeneration. Recent advances have altered the long-standing view of the satellite cell as a committed myogenic stem cell derived directly from the fetal myoblast. The experimental basis for this evolving perspective will be highlighted as will the relationship between the satellite cell and other newly discovered muscle stem cell populations. Finally, advances and prospects for cell-based therapies for muscular dystrophies will be addressed. PMID:14614776

Chen, Jennifer CJ; Goldhamer, David J

2003-01-01

244

STEM2Stern  

NSDL National Science Digital Library

The STEM2Stern Coordination Office works alongside all of the Naval Laboratories and Warfare Centers to offer a broad range of STEM education and outreach programs to support the next generation of scientists and engineers who will bring their talents to U.S. Naval laboratories and warfighting centers. On this site, visitors will find information about the multiple programs offered in each of the fifty states, success stories of students who have gone through these programs, and information for all those interested to get involved (students, educators, parents, and mentors).

2013-07-12

245

Stem Cells Branch Out  

NSDL National Science Digital Library

Heals all manner of ailments, unlimited quantities, tailor-made for you. ⦠No, it's not an advertisement for snake oil but may represent the promise of stem cellsâÂÂcells that have the potential to produce various cell types that make up the body and might therefore provide replacements for tissues damaged by age, trauma, or disease. But the work raises numerous questions as well: Can such promise be true? What is the ethical cost of such developments? Who will fund the necessary R&D? This article introduces a special issue on stem cells.

Pamela Hines (AAAS;); Beverly Purnell (AAAS;); Jean Marx (AAAS;)

2000-02-25

246

STEM on the radio  

NASA Astrophysics Data System (ADS)

Looking for an Internet radio station focusing on programing about science, technology, engineering, and math (STEM)? The U.S. National Science Foundation (NSF) announced on 26 September the launch of Science360 Radio, which it says is the first Internet radio stream dedicated to STEM programing. Science360 includes more than 100 radio shows and podcasts that are available on the Web as well as on iPhone and Android devices. The shows originate from a variety of sources, including NSF, other U.S. government agencies, science organizations, universities, and media outlets. For more information, see http://science360.gov/files/.

Showstack, Randy

2011-10-01

247

Cell Stem Cell Dear Student: Stem Cell Scientists' Advice  

E-print Network

a career in stem cell research?'' ``Besides lending great worth to a scholar's life, leaving spiritual prog or restrict certain types of stem cell research raised profound questions about the field's sustainability. In academia, stem cell research has quickly become institutionalized. Research universities seized the opportu

248

Cancer stem cells and “stemness” genes in neuro-oncology  

Microsoft Academic Search

The main properties of stem cells include long-term self-renewal and the capacity to give rise to one or more types of differentiated progeny. Recently, much evidence was provided that leukemia and tumor maintenance and growth are sustained by a small proportion of cells exhibiting stem cell properties. In neural tumors, stem cells have been detected in glioblastoma, medulloblastoma and ependymoma.

Silvia K. Nicolis

2007-01-01

249

Blood and Marrow Stem Cell Transplant  

MedlinePLUS

... Twitter. What Is a Blood and Marrow Stem Cell Transplant? A blood and marrow stem cell transplant ... the missing white blood cells. Types of Stem Cell Transplants The two main types of stem cell ...

250

Stem Cells and Female Reproduction  

PubMed Central

Several recent findings in stem cell biology have resulted in new opportunities for the treatment of reproductive disease. Endometrial regeneration can be driven by bone marrow derived stem cells. This finding has potential implications for the treatment of uterine disorders. It also supports a new theory for the etiology of endometriosis. The ovaries have been shown to contain stem cells that form oocytes in adults and can be cultured in vitro to develop mature oocytes. Stem cells from the fetus have been demonstrated to lead to microchimerism in the mother and implicated in several maternal diseases. Additionally the placenta may be another source of hematopoietic stem cell. Finally endometrial derived stem cells have been demonstrated to differentiate into non-reproductive tissues. While we are just beginning to understand stem cells and many key questions remain, the potential advantages of stem cells in reproductive biology and medicine are apparent. PMID:19208782

Du, Hongling; Taylor, Hugh S.

2011-01-01

251

Laser biomodulation on stem cells  

NASA Astrophysics Data System (ADS)

Stem cells are views from the perspectives of their function, evolution, development, and cause. Counterintuitively, most stem cells may arise late in development, to act principally in tissue renewal, thus ensuring an organisms long-term survival. Surprisingly, recent reports suggest that tissue-specific adult stem cells have the potential to contribute to replenishment of multiple adult tissues. Stem cells are currently in the news for two reasons: the successful cultivation of human embryonic stem cell lines and reports that adult stem cells can differentiate into developmentally unrelated cell types, such as nerve cells into blood cells. The spotlight on stem cells has revealed gaps in our knowledge that must be filled if we are to take advantage of their full potential for treating devastating degenerative diseases such as Parkinsons's disease and muscular dystrophy. We need to know more about the intrinsic controls that keep stem cells as stem cells or direct them along particular differentiation pathways. Such intrinsic regulators are, in turn, sensitive to the influences of the microenvironment, or niche, where stem cells normally reside. Both intrinsic and extrinsic signals regular stem cell fate and some of these signals have now been identified. Vacek et al and Wang et al have studied the effect of low intensity laser on the haemopoietic stem cells in vitro. There experiments show there is indeed the effect of low intensity laser on the haemopoietic stem cells in vitro, and the present effect is the promotion of haemopoietic stem cells proliferation. In other words, low intensity laser irradiation can act as an extrinsic signal regulating stem cell fate. In this paper, we study how low intensity laser can be used to regulate stem cell fate from the viewpoint of collective phototransduction.

Liu, Timon C.; Duan, Rui; Li, Yan; Li, Xue-Feng; Tan, Li-Ling; Liu, Songhao

2001-08-01

252

Cell Fusion and Stem Cells  

Microsoft Academic Search

\\u000a Differentiation, self-renewal and the ability to readily undergo cell fusion are properties of adult and embryonic stem cells.\\u000a Spontaneous fusion between stem cells, and fusion of stem cells with various differentiated cell types, has been observed\\u000a in many in vitro and in vivo contexts. Stem cell fusion is implicated in many crucial functions during normal development\\u000a and is increasingly being

Alain Silk; Anne E. Powell; Paige S. Davies; Melissa H. Wong

253

Stem Cells in Intraepithelial Neoplasia  

Microsoft Academic Search

\\u000a Tumours are thought to contain a subpopulation of self-renewing stem cells, the so-called cancer stem cells, which maintain the tumour. Moreover, tumours themselves are thought to arise from organ-specific stem cells. In epithelia, transformation of these cells leads to spread of a mutated stem cell clone through the epithelial sheet, leading to the development of a pre-invasive lesion. Barrett’s oesophagus

Nicholas A. Wright

254

Cell Stem Cell Brief Report  

E-print Network

Cell Stem Cell Brief Report Reprogramming of T Cells from Human Peripheral Blood Yuin-Han Loh,1,2,5,9,10,* 1Stem Cell Transplantation Program, Division of Pediatric Hematology Oncology, Children's Hospital, Harvard Medical School, Boston, MA 02115, USA 2Harvard Stem Cell Institute, Cambridge, MA 02138, USA 3

Church, George M.

255

STEMMING the Gap  

ERIC Educational Resources Information Center

America has a gap when it comes to youth pursuing science and technology careers. In an effort to improve the knowledge and application of science, technology, engineering, and math (STEM), after-school programs can work in conjunction with formal in-school curriculum to improve science education. One organization that actively addresses this…

Kahler, Jim; Valentine, Nancy

2011-01-01

256

Epithelial Cells Stem Cells  

E-print Network

Keywords Epithelial Cells Keratins Stem Cells » Prof. Thomas M. Magin Epithelia protect the body, altered cell adhesion and signal- ling. As no molecular therapy for these conditions is available, one that the co-chaperone CHIP can remove mutant aggregated keratins in a cell culture model of EBS, leading

Schüler, Axel

257

Stem Cell Research  

Microsoft Academic Search

The case lays out the controversies surrounding stem cell research, looking specifically at therapeutic cloning and how the embryos produced in this process are produced solely to be destroyed. Thus, the dilemma of whether it is ethical to take one life to save another and the dilemma surrounding human cloning. This case may be used to portray problems in the

R. Freeman; Will Truslow; Pia Ahmad; Bidham Pamar

258

Siemens Stem Academy  

NSDL National Science Digital Library

This website hosts resources for K-12 educators looking to access and share ideas for STEM (science, technology, engineering and mathematics) education. Monthly webinars (archived), lessons, videos, a blog, posters and other materials are available. Professional development opportunities are posted. Some resources require a free registration.

2012-01-01

259

Brain tumour stem cells  

Microsoft Academic Search

The dogma that the genesis of new cells is a negligible event in the adult mammalian brain has long influenced our perception and understanding of the origin and development of CNS tumours. The discovery that new neurons and glia are produced throughout life from neural stem cells provides new possibilities for the candidate cells of origin of CNS neoplasias. The

Rossella Galli; Brent A. Reynolds; Angelo L. Vescovi

2006-01-01

260

Embryonic Stem Cells  

NSDL National Science Digital Library

BioEd Online is an "educational resource for educators, students, and parents" from the Baylor College of Medicine. This is an excellent place to find educational materials and current information in the field of biology. The "Hot Topics" section of this site focus on current events and issues in biology that are "receiving national attention." The controversy surrounding embryonic stem cells, and coverage it receives in news and research publications in the United States and around the world definitely warrants a closer look at this issue. This "Hot Topic" compiled by Joseph Marx, PhD, Nancy Moreno, PhD, and Deanne Erdmann, MS, contains a brief discussion of the stem cell debate, and includes references and links for further reading. Related news articles can be found as well. Be sure to check out the related slide sets for both embryonic stem cells and stem cells. These slide shows are an excellent resource to use in the classroom. Just add the slides you wish to use to your tray and then view or download your slide tray for an instant visual resource.

Erdmann, Deanne; Marx, Joseph; Moreno, Nancy

2006-07-20

261

Advancing Diversity in STEM  

ERIC Educational Resources Information Center

Although progress has been made, greater efforts are needed to promote faculty diversity at the college and university levels, especially in STEM fields. Thus, it is important to elucidate best practices both for increasing awareness of diversity issues pertaining to higher education and for implementing change. This article focuses on the…

Hill, Paul L.; Shaw, Rose A.; Taylor, Jan R.; Hallar, Brittan L.

2011-01-01

262

Cell Stem Cell Perspective  

E-print Network

, genetic vari- ations in iPSCs may originate from the heterogeneous genetic makeup of source cell novo variations (Figure 1B). Third, like ESCs, prolonged culturing of iPSCs may introduce or select in in vitro cultured PSCs, including iPSCs and ESCs. One comprehensive study by the International Stem Cell

Zhang, Yi

263

STEM At Work  

NSDL National Science Digital Library

STEM (Science Technology Engineering & Math) at work, presented by the Florida Advanced Technological Education Center, includes a number of educational puzzles for use in the classroom. Puzzles include an energy audit exercise, measurement of air bag movement, and diesel fuel additive volatility.

2011-03-17

264

Background Information 1. What are stem cells?  

E-print Network

Background Information 1. What are stem cells? 2. What might stem cell research achieve? 3. Why we need to continue research using embryonic stem cells? 4. Time taken for discoveries 5. Examples of stem of Embryonic cell lines 8. Fertility Research using human embryos and blastocysts 1. What are stem cells? Stem

Rambaut, Andrew

265

Short stem shoulder replacement  

PubMed Central

Context: It is agreed that it is important to anatomically reproduce the proximal humeral anatomy when performing a prosthetic shoulder replacement. This can be difficult with a long stemmed prosthesis, in particular if there is little relationship of the metaphysis to the humeral shaft. The ‘short stem’ prosthesis can deal with this problem. Aims: A prospective study assessed the results of total shoulder arthroplasty using a short stem humeral prosthesis, a ceramic humeral head, and a pegged cemented polyethylene glenoid. Materials and methods: Patients with primary shoulder osteoarthritis were recruited into this prospective trial and pre-operatively had the ASES, Constant, SPADI, and DASH scores recorded. The patients were clinically reviewed at the two weeks, eight weeks, one year, and two year mark with completion of a data form. Radiological evaluation was at the eight week, one year and two year follow-up. At the one and two year follow-up the satisfaction rating, the range of passive and active motion, Constant, ASES, SPADI, DASH and pain results were recorded and analysed with SPPS 20. Results: During the study period 97 short stem, ceramic head total shoulder replacements were carried out. At the time of follow-up 12 were two years from operation and 38 one year from operation. Active elevation was overall mean 160 degrees. Constant scores were 76 at 1 year, and 86 at 2 years, ASES 88 and 93, and satisfaction 96% and 98% respectively at one and 2 year follow up. There were no problems during insertion of the humeral prosthesis, or any radiolucent lines or movement of the prosthesis on later radiographs. Conclusion: The short stem prosthesis had no complications, and on follow up radiographs good bone fixation. These fairly short term clinical results were overall good. PMID:25258497

Bell, Simon N.; Coghlan, Jennifer A.

2014-01-01

266

Inflammation and cancer stem cells.  

PubMed

Cancer stem cells are becoming recognised as being responsible for metastasis and treatment resistance. The complex cellular and molecular network that regulates cancer stem cells and the role that inflammation plays in cancer progression are slowly being elucidated. Cytokines, secreted by tumour associated immune cells, activate the necessary pathways required by cancer stem cells to facilitate cancer stem cells progressing through the epithelial-mesenchymal transition and migrating to distant sites. Once in situ, these cancer stem cells can secrete their own attractants, thus providing an environment whereby these cells can continue to propagate the tumour in a secondary niche. PMID:23941828

Shigdar, Sarah; Li, Yong; Bhattacharya, Santanu; O'Connor, Michael; Pu, Chunwen; Lin, Jia; Wang, Tao; Xiang, Dongxi; Kong, Lingxue; Wei, Ming Q; Zhu, Yimin; Zhou, Shufeng; Duan, Wei

2014-04-10

267

A Class IV Chitinase Is Up-Regulated by Fungal Infection and Abiotic Stresses and Associated with Slow-Canker-Growth Resistance to Cronartium ribicola in Western White Pine (Pinus monticola).  

PubMed

ABSTRACT In the present study, in a candidate gene approach, a class IV chitinase gene (PmCh4A) of pathogenesis-related family three was cloned and characterized in western white pine (Pinus monticola). PmCh4A chitinase expression in the different organs of healthy seedlings was below levels detectable by western immunoblot analysis using an antibody raised against PmCh4A protein. However, a 27-kDa isozyme of PmCh4A accu mulated in both susceptible and slow-canker-growth (SCG) resistant seedlings after infection by Cronartium ribicola. As with fungal infection, the application of a signal chemical (methyl jasmonate) and a protein phosphatase 1 and 2A inhibitor (okadaic acid) increased the PmCh4A protein accumulation. Furthermore, another 26-kDa isozyme was expressed specifically in SCG resistant seedlings, providing a potential tool for marker-assisted selection in forest breeding. Wounding treatment also induced expression of the protein. These data suggest that the class IV chitinase PmCh4A is involved in the defense response of western white pine to infection and abiotic stresses. PMID:18943122

Liu, Jun-Jun; Ekramoddoullah, Abul K M; Zamani, Arezoo

2005-03-01

268

Materials as stem cell regulators  

NASA Astrophysics Data System (ADS)

The stem cell/material interface is a complex, dynamic microenvironment in which the cell and the material cooperatively dictate one another's fate: the cell by remodelling its surroundings, and the material through its inherent properties (such as adhesivity, stiffness, nanostructure or degradability). Stem cells in contact with materials are able to sense their properties, integrate cues via signal propagation and ultimately translate parallel signalling information into cell fate decisions. However, discovering the mechanisms by which stem cells respond to inherent material characteristics is challenging because of the highly complex, multicomponent signalling milieu present in the stem cell environment. In this Review, we discuss recent evidence that shows that inherent material properties may be engineered to dictate stem cell fate decisions, and overview a subset of the operative signal transduction mechanisms that have begun to emerge. Further developments in stem cell engineering and mechanotransduction are poised to have substantial implications for stem cell biology and regenerative medicine.

Murphy, William L.; McDevitt, Todd C.; Engler, Adam J.

2014-06-01

269

Materials as stem cell regulators  

PubMed Central

The stem cell/material interface is a complex, dynamic microenvironment in which the cell and the material cooperatively dictate one another's fate: the cell by remodelling its surroundings, and the material through its inherent properties (such as adhesivity, stiffness, nanostructure or degradability). Stem cells in contact with materials are able to sense their properties, integrate cues via signal propagation and ultimately translate parallel signalling information into cell fate decisions. However, discovering the mechanisms by which stem cells respond to inherent material characteristics is challenging because of the highly complex, multicomponent signalling milieu present in the stem cell environment. In this Review, we discuss recent evidence that shows that inherent material properties may be engineered to dictate stem cell fate decisions, and overview a subset of the operative signal transduction mechanisms that have begun to emerge. Further developments in stem cell engineering and mechanotransduction are poised to have substantial implications for stem cell biology and regenerative medicine. PMID:24845994

Murphy, William L.; McDevitt, Todd C.; Engler, Adam J.

2014-01-01

270

Characterization of rhizosphere bacteria for control of phytopathogenic fungi of tomato.  

PubMed

Fluorescent Pseudomonas spp., isolated from rhizosphere soil of tomato and pepper plants, were evaluated in vitro as potential antagonists of fungal pathogens. Strains were characterized using the API 20NE biochemical system, and tested against the causal agents of stem canker and leaf blight (Alternaria alternata f. sp. lycopersici), southern blight (Sclerotium rolfsii Sacc.), and root rot (Fusarium solani). To this end, dual culture antagonism assays were carried out on 25% Tryptic Soy Agar, King B medium, and Potato Dextrose Agar to determine the effect of the strains on mycelial growth of the pathogens. The effect of two concentrations of FeCl(3) on antagonism against Alternaria alternata f. sp. lycopersici was also tested. In addition, strains were screened for ability to produce exoenzymes and siderophores. Finally, the selected Pseudomonas strain, PCI2, was evaluated for effect on tomato seedling development and as a potential candidate for controlling tomato damping-off caused by Sclerotium rolfsii Sacc., under growth chamber conditions. All strains significantly inhibited Alternaria alternata f. sp. lycopersici, particularly in 25% TSA medium. Antagonistic effect on Sclerotium rolfsii Sacc. and Fusarium solani was greater on King B medium. Protease was produced by 30% of the strains, but no strains produced cellulase or chitinase. Growth chamber studies resulted in significant increases in plant stand as well as in root dry weight. PCI2 was able to establish and survive in tomato plants rhizosphere after 40 days following planting of bacterized seeds. PMID:21507555

Pastor, Nicolás; Carlier, Evelin; Andrés, Javier; Rosas, Susana B; Rovera, Marisa

2012-03-01

271

STEM Equity Pipeline  

NSDL National Science Digital Library

As a past president of the National Academy of Engineering put it, "A consequence of lack of diversity...[is that] we pay an opportunity cost, a cost in designs not thought of, in solutions not produced." Thus, in an effort to increase the diversity of the Science, Technology, Engineering and Mathematics (STEM) workforce, STEM Equity Pipeline was developed. The "Online Resources" section of their website offers visitors a wide variety of resources, including "pamphlets/brochures", "posters", "scholarships" and "videos". The "Curriculum" resource is particularly rich and it offers over 50 websites that contain single activities, whole lesson plans or hands-on explorations. Some of the titles visitors might find valuable are "Some Disassembly Required", which employs reverse engineering (or taking things apart) to learn how they work, "Teaching Tool for Introductory Programming Concepts", to teach students computer programming in a 3D environment, and "Home Science Adventures", science lessons and plans for home- schoolers.

2011-06-17

272

Stem Cell Transplant  

Microsoft Academic Search

\\u000a Hematopoietic stem cell transplant (HSCT) began in humans in the late 1950s and since that time more than 800,000 people have\\u000a been treated with this procedure. To date 150,000 patients are living 5 years or more post transplant, with this number expanding\\u000a rapidly [1]. As advances have been made in refining HSCT and making it more accessible, a larger proportion

Jean C. Yi; Karen L. Syrjala

273

Update on stem cell \\  

Microsoft Academic Search

Summary  Allogeneic haematopoietic stem cell transplantation in humans results in true biological chimeras. Whilst circulating haematopoietic\\u000a cells become donor genotype after transplantation, other cells believed to remain recipient in origin. It was only recently\\u000a realized that bone marrow-derived cells may also contribute to non-haematopoietic tissues, suggesting a level of plasticity\\u000a not previously expected. New concepts in ontogenesis and developmental potential of

A. Spyridonidis

2010-01-01

274

Brain cancer stem cells  

Microsoft Academic Search

Cancers comprise heterogeneous cells, ranging from highly proliferative immature precursors to more differentiated cell lineages.\\u000a In the last decade, several groups have demonstrated the existence of cancer stem cells in both nonsolid solid tumors, including\\u000a some of the brain: glioblastoma multiforme (GBM), medulloblastoma, and ependymoma. These cells, like their normal counterpart\\u000a in homologous tissues, are multipotent, undifferentiated, self-sustaining, yet transformed

Sara G. M. Piccirillo; Elena Binda; Roberta Fiocco; Angelo L. Vescovi; Khalid Shah

2009-01-01

275

Melanoma Stem Cells  

Microsoft Academic Search

\\u000a The hypothesis that tumor initiation and growth are driven by a subpopulation of malignant cells, that is, cancer stem cells\\u000a (CSCs), has received considerable attention. The CSC concept predicts that the design of novel therapies that ablate CSCs\\u000a or target CSC-specific protumorigenic signaling pathways might result in more durable therapeutic responses in cancer patients\\u000a than those achieved by therapeutic approaches

Tobias Schatton; Markus H. Frank

276

AccessSTEM  

NSDL National Science Digital Library

The University of Washington's award-winning DO-IT Center (Disabilities, Opportunities, Internetworking and Technology) collaborates with AccessSTEM, which has been funded by the National Science Foundation since 2002. AccessSTEM, aims to "broaden participation in STEM fields and improve those fields with the perspectives and expertise of people with disabilities." Visitors to the site who are disabled students, faculty, employees, or just the interested public will find much to peruse or read in-depth. There is the longitudinal transition study link in the "For Faculty and Employees" section that tracks the college and career paths of students with disabilities who used the DO-IT program. Visitors will find the "Promising Practices" section, also in the Faculty and Employees section, to be filled with useful articles and innovations. There is "A Smart Board in the Classroom: A Promising Practice for Engaging Students", which addresses how the use of a Smart Board can aid students with attention deficits, visual impairments, and other disabling conditions without bringing the whole class' attention to them.

277

Melanocytes, melanocyte stem cells, and melanoma stem cells  

PubMed Central

Melanocyte stem cells differ greatly from melanoma stem cells; the former provide pigmented cells during normal tissue homeostasis and repair, while the latter play an active role in a lethal form of cancer. These two cell types share several features and can be studied by similar methods. Aspects held in common by both melanocyte stem cells and melanoma stem cells include their expression of shared biochemical markers, a system of similar molecular signals necessary for their maintenance, and a requirement for an ideal niche microenvironment for providing these factors. This review provides a perspective of both these cell types and discusses potential models of stem cell growth and propagation. Recent findings provide a strong foundation for the development of new therapeutics directed at isolating and manipulating melanocyte stem cells for tissue engineering or at targeting and eradicating melanoma specifically, while sparing non-tumor cells. PMID:23438380

Lang, Deborah; Mascarenhas, Joseph B.; Shea, Christopher R.

2012-01-01

278

Immune Responses to Stem Cells and Cancer Stem Cells  

Microsoft Academic Search

\\u000a The demonstrated capacity and potential of pluripotent stem cells to repair the damaged tissues holds great promise in development\\u000a of novel cell replacement therapeutics for treating various chronic and degenerative diseases. However, previous reports show\\u000a that stem cell therapy, in autologous and allogeneic settings, triggers immune responses to stem cells as shown by lymphocyte\\u000a infiltration and inflammation. Therefore, an important

Xiao-Feng Yang; Hong Wang

279

Biomaterials as Stem Cell Niche: Cardiovascular Stem Cells  

Microsoft Academic Search

\\u000a A tissue-specific stem cell niche functions to direct either self-renewal or differentiation. The niche comprises all local\\u000a cues that can be sensed by the cell including soluble and insoluble signals, physical forces and cell–cell contacts. Approximating\\u000a the stem cell niche through the utilization of biomaterials may give rise to a greater understanding of the biology of the\\u000a stem cell niche

Ge Zhang; Laura J. Suggs

280

EMBRYONIC STEM CELLS/INDUCED PLURIPOTENT STEM CELLS Long-Term, Stable Differentiation of Human Embryonic Stem  

E-print Network

EMBRYONIC STEM CELLS/INDUCED PLURIPOTENT STEM CELLS Long-Term, Stable Differentiation of Human Embryonic Stem Cell-Derived Neural Precursors Grafted into the Adult Mammalian Neostriatum IGOR NASONKIN Words. Cellular therapy · Embryonic stem cells · Neural differentiation · Neural induction · Neural stem

Ryugo, David K.

281

Salicylic acid-mediated establishment of the compatibility between Alternaria brassicicola and Brassica juncea is mitigated by abscisic acid in Sinapis alba.  

PubMed

This work addresses the changes in the phytohormonal signature in the recognition of the necrotrophic fungal pathogen Alternaria brassicicola by susceptible Brassica juncea and resistant Sinapis alba. Although B. juncea, S. alba and Arabidopsis all belong to the same family, Brassicaceae, the phytohormonal response of susceptible B. juncea towards this pathogen is unique because the latter two species express non-host resistance. The differential expression of the PR1 gene and the increased level of salicylic acid (SA) indicated that an SA-mediated biotrophic mode of defence response was triggered in B. juncea upon challenge with the pathogen. Compared to B. juncea, resistant S. alba initiated enhanced abscisic acid (ABA) and jasmonic acid (JA) responses following challenge with this pathogen, as revealed by monitoring the expression of ABA-related genes along with the concentration of ABA and JA. Furthermore, these results were verified by the exogenous application of ABA on B. juncea leaves prior to challenge with A. brassicicola, which resulted in a delayed disease progression, followed by the inhibition of the pathogen-mediated increase in SA response and enhanced JA levels. Therefore, it seems that A. brassicicola is steering the defence response towards a biotrophic mode by mounting an SA response in susceptible B. juncea, whereas the enhanced ABA response of S. alba not only counteracts the SA response but also restores the necrotrophic mode of resistance by enhancing JA biosynthesis. PMID:23770593

Mazumder, Mrinmoy; Das, Srirupa; Saha, Upala; Chatterjee, Madhuvanti; Bannerjee, Kaushik; Basu, Debabrata

2013-09-01

282

Antifungal activity of food additives in vitro and as ingredients of hydroxypropyl methylcellulose-lipid edible coatings against Botrytis cinerea and Alternaria alternata on cherry tomato fruit.  

PubMed

The antifungal activity of food additives or 'generally recognized as safe' (GRAS) compounds was tested in vitro against Botrytis cinerea and Alternaria alternata. Radial mycelial growth of each pathogen was measured in PDA Petri dishes amended with food preservatives at 0.2, 1.0, or 2.0% (v/v) after 3, 5, and 7 days of incubation at 25 °C. Selected additives and concentrations were tested as antifungal ingredients of hydroxypropyl methylcellulose (HPMC)-lipid edible coatings. The curative activity of stable coatings was tested in in vivo experiments. Cherry tomatoes were artificially inoculated with the pathogens, coated by immersion about 24 h later, and incubated at 20 °C and 90% RH. Disease incidence and severity (lesion diameter) were determined after 6, 10, and 15 days of incubation and the 'area under the disease progress stairs' (AUDPS) was calculated. In general, HPMC-lipid antifungal coatings controlled black spot caused by A. alternata more effectively than gray mold caused by B. cinerea. Overall, the best results for reduction of gray mold on cherry tomato fruit were obtained with coatings containing 2.0% of potassium carbonate, ammonium phosphate, potassium bicarbonate, or ammonium carbonate, while 2.0% sodium methylparaben, sodium ethylparaben, and sodium propylparaben were the best ingredients for coatings against black rot. PMID:24026010

Fagundes, Cristiane; Pérez-Gago, María B; Monteiro, Alcilene R; Palou, Lluís

2013-09-16

283

FTIR spectroscopic evaluation of changes in the cellular biochemical composition of the phytopathogenic fungus Alternaria alternata induced by extracts of some Greek medicinal and aromatic plants  

NASA Astrophysics Data System (ADS)

In this study, the biological activity of aquatic extracts of selected Greek medicinal and aromatic plants to the phytopathogenic fungus Alternaria alternata was investigated. Lamiaceae species (Hyssopus officinalis L., Melissa officinalis L., Origanum dictamnus L., Origanum vulgare L. and Salvia officinalis L.) were found to enhance significantly the mycelium growth whereas Crocus sativus appears to inhibit it slightly. M. officinalis and S. officinalis caused the highest stimulation in mycelium growth (+97%) and conidia production (+65%) respectively. In order to further investigate the bioactivity of plant extracts to A. alternata, we employed Fourier Transform Infrared Spectroscopy (FTIR). Differences of original spectra were assigned mainly to amides of proteins. The second derivative transformation of spectra revealed changes in spectral regions corresponding to absorptions of the major cellular constituents such as cell membrane and proteins. Principal component analysis of the second derivative transformed spectra confirmed that fatty acids of the cell membranes, amides of proteins and polysaccharides of the cell wall had the major contribution to data variation. FTIR band area ratios were found to correlate with fungal mycelium growth.

Skotti, Efstathia; Kountouri, Sophia; Bouchagier, Pavlos; Tsitsigiannis, Dimitrios I.; Polissiou, Moschos; Tarantilis, Petros A.

2014-06-01

284

Role of the Alternaria alternata Blue-Light Receptor LreA (White-Collar 1) in Spore Formation and Secondary Metabolism  

PubMed Central

Alternaria alternata is a filamentous fungus that causes considerable loss of crops of economically important feed and food worldwide. It produces more than 60 different secondary metabolites, among which alternariol (AOH) and altertoxin (ATX) are the most important mycotoxins. We found that mycotoxin production and spore formation are regulated by light in opposite ways. Whereas spore formation was largely decreased under light conditions, the production of AOH was stimulated 2- to 3-fold. ATX production was even strictly dependent on light. All light effects observed could be triggered by blue light, whereas red light had only a minor effect. Inhibition of spore formation by light was reversible after 1 day of incubation in the dark. We identified orthologues of genes encoding the Neurospora crassa blue-light-perceiving white-collar proteins, a cryptochrome, a phytochrome, and an opsin-related protein in the genome of A. alternata. Deletion of the white-collar 1 (WC-1) gene (lreA) resulted in derepression of spore formation in dark and in light. ATX formation was strongly induced in the dark in the lreA mutant, suggesting a repressing function of LreA, which appears to be released in the wild type after blue-light exposure. In addition, light induction of AOH formation was partially dependent on LreA, suggesting also an activating function. A. alternata ?lreA was still able to partially respond to blue light, indicating the action of another blue-light receptor system. PMID:24532063

Pruss, Sonja; Fetzner, Ramona; Seither, Kristin; Herr, Andreas; Pfeiffer, Erika; Metzler, Manfred; Lawrence, Christopher B.

2014-01-01

285

Stem cells in veterinary medicine  

Microsoft Academic Search

The stem cell field in veterinary medicine continues to evolve rapidly both experimentally and clinically. Stem cells are\\u000a most commonly used in clinical veterinary medicine in therapeutic applications for the treatment of musculoskeletal injuries\\u000a in horses and dogs. New technologies of assisted reproduction are being developed to apply the properties of spermatogonial\\u000a stem cells to preserve endangered animal species. The

Lisa A Fortier; Alexander J Travis

2011-01-01

286

Stem cells: Implications for urology  

Microsoft Academic Search

Stem cells are characterized by their potential immortality and are capable of self-renewal and differentiation. Stem cells\\u000a are proposed to provide the potential to cure degenerative diseases and to give important clues regarding human development\\u000a and aging. However, stem cell research has evoked enthusiasm and passionate debate regarding the ethics of their use in medicine\\u000a and reproduction. In this article,

Kirk C. Lo; Shannon Whirledge; Dolores J. Lamb

2005-01-01

287

Stem Cell Basics About this document  

E-print Network

that are the focus of scientific research, and the potential use of stem cells in research and in treating disease1 Stem Cell Basics About this document This primer on stem cells is intended for anyone who wishes to learn more about the biological properties of stem cells, the important questions about stem cells

Bandettini, Peter A.

288

Human Embryonic Stem Cell Registry  

NSDL National Science Digital Library

The National Institutes of Health (NIH) has recently released the Human Embryonic Stem Cell Registry in response to the President's announcement on August 9, 2001 to allow federal funds for stem cell research. The site lists the eleven laboratories or companies that meet the specific criteria for approved stem cell lines and explains the criteria themselves. The NIH gives the number of actual lines for each entity, the NIC and providers code for each, as well as contact information. The Website also provides links to those seeking additional information about NIH stem cell information, grants and funding opportunities, technology transfer issues, and further facts about the NIH.

2001-01-01

289

Mechanotransduction: Tuning Stem Cells Fate  

PubMed Central

It is a general concern that the success of regenerative medicine-based applications is based on the ability to recapitulate the molecular events that allow stem cells to repair the damaged tissue/organ. To this end biomaterials are designed to display properties that, in a precise and physiological-like fashion, could drive stem cell fate both in vitro and in vivo. The rationale is that stem cells are highly sensitive to forces and that they may convert mechanical stimuli into a chemical response. In this review, we describe novelties on stem cells and biomaterials interactions with more focus on the implication of the mechanical stimulation named mechanotransduction. PMID:24956164

D'Angelo, Francesco; Tiribuzi, Roberto; Armentano, Ilaria; Kenny, Jose Maria; Martino, Sabata; Orlacchio, Aldo

2011-01-01

290

STEm Minority Graduate Program  

SciTech Connect

ABSTRACT The state of science, technology, engineering and math (STEM) education in the United States has seen some unfavorable assessments over the past decade. In early February, 2010 the House of Representatives heard testimony on undergraduate and graduate education. The message from the panel, which included experts from academia, STEM-based industries, and the National Science Foundation (NSF) was dire and required an urgent response. The experts along with the committee���¢��������s chairperson, U. S. Representative Daniel Lipinski (D-IL) cited that the complexity of Science, Technology, Engineering, and Mathematics applications and coursework and the methodology utilized to teach these subjects are forcing students out of these disciplines. As the National Academies described in its 2007 report Rising Above the Gathering Storm, successful STEM education is not just an academic pursuit���¢��������it���¢��������s a necessity for competing in the knowledge-based economy that the United States had a key role in creating. The potential for action is being made available again as the America COMPETES Act of 2007 is up for reauthorization. Its initial focus was on STEM education at the K-12 levels, but efforts at the undergraduate and graduate levels are needed to retain students to fill the jobs left vacant as baby boomers retire. The Educational Advancement Alliance, Inc. (EAA) has for two decades created programs that have not only addressed the issues of ensuring that students are aptly prepared for college but have focused its efforts over the past decade on increasing the number of students who pursue degrees in STEM disciplines. For the EAA, the introduction of the wonders of science begins at the elementary and middle school level via the Learning Lab, a state-of-the-art mobile science laboratory that visits students in grades 4-6 at the various schools throughout Philadelphia and The Math/Tech Academy which meets on Saturdays for students in grades 5-7. For the past two years the EAA has assisted college graduates in their quest to attain advanced degrees in STEM by providing fellowships. The EAA continued this effort by recruiting and providing fellowships to students who aspired to continue their education at the graduate level. The fellowships provided funding for tuition, fees, books, technology, and stipends to assist with room, board, and living expenses during the academic year and salary, transportation, and living expenses to those students who secured internships with the Department of Energy. Additionally the EAA designed and implemented needed support systems to ensure successful completion of the Masters degree programs, including but not limited to membership in professional associations, attendance at industry and academic conferences, and professional development workshops, and tutorial assistance if needed. This program assisted over 80 students directly and society-at-large by helping to educate and develop future physicists, engineers, biostatisticians, and researchers who will have the necessary skillsets to fill the increasing numbers of positions that require such expertise.

Kaen E. Nicholas

2012-09-20

291

Stem Cell Glycolipids  

Microsoft Academic Search

Glycolipids are compounds containing one or more monosaccharide residues bound by a glycosidic linkage to a hydrophobic moiety.\\u000a Because of their expression patterns and the intracellular localization patterns, glycolipids, including stage-specific embryonic\\u000a antigens (SSEA-3, SSEA-4, and possibly SSEA-1) and gangliosides (e.g., GD3, GD2, and A2B5 antigens), have been used as marker\\u000a molecules of stem cells. In this review, I will

Makoto Yanagisawa

292

Stem Cell Research  

SciTech Connect

We have identified a population of primitive cells in normal human post-natal bone marrow that can, at the single cell level, differentiate in many ways and also proliferate extensively. These cells can differentiate in vitro into most mesodermal cell types (for example, bone cells, and others), as well as cells into cells of the nervous system. The finding that stem cells exist in post-natal tissues with previously unknown proliferation and differentiation potential opens up the possibility of using them to treat a host of degenerative, traumatic or congenital diseases.

Verfaillie, Catherine (University of Minnesota) [University of Minnesota

2002-01-23

293

STEM Colorado: Galactic Communication  

NSDL National Science Digital Library

This applet illustrates the challenges of communicating with extraterrestrial civilizations. It shows a galaxy with a diameter of 100,000 light years. The user is able to control the average lifetime of communicating civilizations and the birth rate of such civilizations in the Milky Way galaxy. After hitting start, Earth appears and begins transmitting its signal. When Earth receives a signal from another civilization, a line appears connecting them. The applet will automatically pause when Earth ceases to communicate. Signals change color when a civilization ceases to exist. This is part of a larger collection of applets by STEM Colorado focused mostly on topics in astronomy.

Mccray, Richard; Koelemay, Andrew

2008-08-28

294

STEM Colorado: Doppler Shift  

NSDL National Science Digital Library

This applet demonstrates the Doppler shift. The user can control the frequency of the sound source and the sound speed. The chart recorder at the bottom displays the wave crests as detected by the receiver and their frequency. It also displays the instantaneous wavelength if the ear is at rest. The user can drag the source or the receiver to any location in the display and choose the velocity of each. This is part of a larger collection of applets by STEM Colorado focused mostly on topics in astronomy.

Mccray, Richard; Koelemay, Andrew

2008-08-30

295

6. VIEW SHOWING UPRIGHT OUTLET GATE WHEEL, STEM AND STEM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. VIEW SHOWING UPRIGHT OUTLET GATE WHEEL, STEM AND STEM GUIDE, WITH LOG ACCESS STRUCTURE, LOOKING WEST - High Mountain Dams in Upalco Unit, Bluebell Lake Dam, Ashley National Forest, 11.2 miles Northwest of Swift Creek Campground, Mountain Home, Duchesne County, UT

296

5. VIEW SHOWING UPRIGHT OUTLET GATE WHEEL, STEM AND STEM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW SHOWING UPRIGHT OUTLET GATE WHEEL, STEM AND STEM GUIDE, WITH LOG ACCESS STRUCTURE, LOOKING SOUTHEAST - High Mountain Dams in Upalco Unit, Bluebell Lake Dam, Ashley National Forest, 11.2 miles Northwest of Swift Creek Campground, Mountain Home, Duchesne County, UT

297

Learning for STEM Literacy: STEM Literacy for Learning  

ERIC Educational Resources Information Center

We are in the STEM generation whose comprehensive purpose is to resolve (1) societal needs for new technological and scientific advances; (2) economic needs for national security; and (3) personal needs to become a fulfilled, productive, knowledgeable citizen. STEM specifically refers to science, technology, engineering, and mathematics, but now…

Zollman, Alan

2012-01-01

298

An Ecological Model of STEM Education: Operationalizing STEM FOR ALL  

ERIC Educational Resources Information Center

This article describes a framework for how to provide more accessible, relevant, and effective instruction in science, technology, engineering, and mathematics (STEM) education to all students. The STEM for All initiative asserts that all students, including those with disabilities and other diverse learning needs, should be included in meaningful…

Basham, James D.; Israel, Maya; Maynard, Kathie

2010-01-01

299

Multilocus Variable-Number-Tandem-Repeats Analysis (MLVA) distinguishes a clonal complex of Clavibacter michiganensis subsp. michiganensis strains isolated from recent outbreaks of bacterial wilt and canker in Belgium  

PubMed Central

Background Clavibacter michiganensis subsp. michiganensis (Cmm) causes bacterial wilt and canker in tomato. Cmm is present nearly in all European countries. During the last three years several local outbreaks were detected in Belgium. The lack of a convenient high-resolution strain-typing method has hampered the study of the routes of transmission of Cmm and epidemiology in tomato cultivation. In this study the genetic relatedness among a worldwide collection of Cmm strains and their relatives was approached by gyrB and dnaA gene sequencing. Further, we developed and applied a multilocus variable number of tandem repeats analysis (MLVA) scheme to discriminate among Cmm strains. Results A phylogenetic analysis of gyrB and dnaA gene sequences of 56 Cmm strains demonstrated that Belgian Cmm strains from recent outbreaks of 2010–2012 form a genetically uniform group within the Cmm clade, and Cmm is phylogenetically distinct from other Clavibacter subspecies and from non-pathogenic Clavibacter-like strains. MLVA conducted with eight minisatellite loci detected 25 haplotypes within Cmm. All strains from Belgian outbreaks, isolated between 2010 and 2012, together with two French strains from 2010 seem to form one monomorphic group. Regardless of the isolation year, location or tomato cultivar, Belgian strains from recent outbreaks belonged to the same haplotype. On the contrary, strains from diverse geographical locations or isolated over longer periods of time formed mostly singletons. Conclusions We hypothesise that the introduction might have originated from one lot of seeds or contaminated tomato seedlings that was the source of the outbreak in 2010 and that these Cmm strains persisted and induced infection in 2011 and 2012. Our results demonstrate that MLVA is a promising typing technique for a local surveillance and outbreaks investigation in epidemiological studies of Cmm. PMID:23738754

2013-01-01

300

FDA Warns About Stem Cell Claims  

MedlinePLUS

... Biologics Articulos en Espanol FDA Warns About Stem Cell Claims Search the Consumer Updates Section Researchers hope ... forming system. back to top Regulation of Stem Cells FDA regulates stem cells in the U.S. to ...

301

What's It Like to Donate Stem Cells?  

MedlinePLUS

... learn more What’s it like to donate stem cells? People usually volunteer to donate stem cells for ... autologous transplant. If you want to donate stem cells for someone else People who want to donate ...

302

Sources of Stem Cells for Transplant  

MedlinePLUS

... Donor matching for allogeneic transplant Sources of stem cells for transplant There are 3 possible sources of ... blood transplants are being actively studied. Which stem cell source is best? All 3 sources of stem ...

303

Stem Cell Transplant Patients and Fungal Infections  

MedlinePLUS

... About CDC.gov . Fungal Diseases Share Compartir Stem Cell Transplant Patients and Fungal Infections As a stem ... Top of Page Preventing fungal infections in stem cell transplant patients Fungi are difficult to avoid because ...

304

7 CFR 29.6039 - Stem rot.  

Code of Federal Regulations, 2012 CFR

... 2012-01-01 2012-01-01 false Stem rot. 29.6039 Section 29.6039 Agriculture... Standards Definitions § 29.6039 Stem rot. The deterioration of an uncured or frozen stem resulting from bacterial action....

2012-01-01

305

7 CFR 29.6039 - Stem rot.  

Code of Federal Regulations, 2011 CFR

... 2011-01-01 2011-01-01 false Stem rot. 29.6039 Section 29.6039 Agriculture... Standards Definitions § 29.6039 Stem rot. The deterioration of an uncured or frozen stem resulting from bacterial action....

2011-01-01

306

7 CFR 29.6039 - Stem rot.  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 2010-01-01 false Stem rot. 29.6039 Section 29.6039 Agriculture... Standards Definitions § 29.6039 Stem rot. The deterioration of an uncured or frozen stem resulting from bacterial action....

2010-01-01

307

Defining Vascular Stem Cells  

PubMed Central

Mesenchymal stem cells (MSCs) exist in most adult tissues and have been located near or within blood vessels. Although “perivascular” has been commonly used to describe such locations, increasing evidence points at the vessel wall as the exact location. Thus, “vascular stem cells (VSCs)” is recommended as a more accurate term for MSCs. Furthermore, 2 cell populations, namely pericytes and adventitial progenitor cells (APCs), are the likely VSCs. The pericyte evidence relies on the so-called pericyte-specific markers, but none of these markers is pericyte specific. In addition, pericytes appear to be too functionally diverse and sophisticated to have a large differentiation capacity. On the other hand, APCs are more naïve functionally and, therefore, more akin to being VSCs. In vitro, these cells spontaneously differentiate into pericytes, and can be induced to differentiate into vascular cells (endothelial and smooth muscle cells) and mesenchymal cells (eg, bone, cartilage, and fat). In vivo, indirect evidence also points to their ability to differentiate into mesenchymal cells of their native tissue (eg, fat). Moreover, they possess a large paracrine capacity and, therefore, can help maintain tissue homeostasis by encouraging the replication and differentiation of mesenchymal cells locally. These proposed in vivo functions are areas of interest for future research on VSCs. PMID:23330734

Lue, Tom F.

2013-01-01

308

Stem cells and brain cancer  

Microsoft Academic Search

One of the most devastating CNS pathologies is brain cancer. The undifferentiated character of brain tumor cells and recent reports of cancer stem cells prompt questions regarding the involvement of normal stem\\/progenitor cells in brain tumor biology, their potential contribution to the tumor itself, and whether they are the cause or the consequence of tumor initiation and progression. The cancer

Elena I. Fomchenko; Eric C. Holland

2005-01-01

309

International stem cell research considerations  

Microsoft Academic Search

Legislative bodies in the international arena and in individual countries are actively engaged in developing policies regarding the establishment, distribution and use of human embryonic stem cells. Present and anticipated policies concerning research on human adult and embryonic stem cells of possible medical importance reflect the wide spectrum of popular views that range from complete rejection to enthusiastic support. Since

Heiner Westphal

2002-01-01

310

Stem cell transplantation; Iranian experience.  

PubMed

From March 1991 through 31st December 2007, 2042 patients underwent stem cell transplantation at the Hematology-Oncology and Stem Cell Transplantation Research Center, affiliated to Tehran University of Medical Sciences. These transplantations included 1405 allogeneic stem cell transplantation, 624 autologous stem cell transplantation, and 13 syngeneic stem cell transplantation. Stem cell transplantation was performed for various diseases including acute myelogenous leukemia, acute lymphoblastic leukemia, chronic myelogenous leukemia, chronic lymphoblastic leukemia, thalassemia major, sickle cell thalassemia, sickle cell disease, multiple myeloma, myelodysplasia, mucopolysaccharidosis, paroxysmal nocturnal hemoglobinuria, non-Hodgkin's lymphoma, Hodgkin's disease, severe aplastic anemia, plasma cell leukemia, Niemann-Pick disease, Fanconi anemia, severe combine immunodeficiency, congenital neutropenia, leukocyte adhesion deficiencies, Chediak-Higashi syndrome, osteopetrosis, histiocytosis X, Hurler syndrome, amyloidosis, systemic sclerosis, breast cancer, Ewing's sarcoma, testicular cancer, germ cell tumors, neuroblastoma, medulloblastoma, renal cell carcinoma, nasopharyngeal carcinoma, ovarian cancer, Wilms' tumor, rhabdomyosarcoma, pancreatoblastoma, and multiple sclerosis. We had 105 cellular therapies for postmyocardial infarction, multiple sclerosis, cirrhosis, head of femur necrosis, and renal cell carcinoma. About 30 patients were retransplanted in this center. About 74.9% of the patients (1530 of 2042) remained alive between one to 168 months after stem cell transplantation. Nearly 25.1% (512 of 2042) of our patients died after stem cell transplantation. The causes of deaths were relapse, infections, hemorrhagic cystitis, graft versus host disease, and others. PMID:19111033

Ghavamzadeh, Ardeshir; Alimoghaddam, Kamran; Alimogaddam, Kamran; Jahani, Mohammad; Mousavi, Seied Asadollah; Mousavi, Seyed Asadollah; Iravani, Masood; Bahar, Babak; Khodabandeh, Ali; Khatami, Farnaz; Ghaffari, Fatemeh; Jalali, Arash

2009-01-01

311

National STEM Promoting Awareness of  

E-print Network

, Engineering and Math (STEM) among Underrepresented Students Blanket Purchase Agreement (BPA) available for all of funding (See BPA SOP) · BPA cost per "Call" (Plus per diem based on JTR) STEM Awareness Program - $17 Environmental Scan. About the BPA The U.S. Army Corps of Engineers has developed a Blanket Purchase Agreement

US Army Corps of Engineers

312

Regulating the leukemia stem cell  

PubMed Central

Leukemia stem cells (LSCs) are responsible for sustaining and propagating malignant disease, and, as such, are promising targets for therapy. Studies of human LSCs have served an important role in defining the major tenets of the cancer stem cell model, which center on the frequencies of cancer stem cells, their potential hierarchical organization, and their degree of maturation. LSCs in acute myeloid leukemia (AML) have recently been studied using mouse syngeneic models of leukemia induced by MLL oncogenes. These studies have revealed that LSCs are more analogous to progenitor cells and employ embryonic stem cell-like genetic programs for their maintenance, prompting a refinement of the original cancer stem cell model with important implications for design of therapies to selectively target LSCs. PMID:19959097

Cleary, Michael L.

2009-01-01

313

DEVELOPMENTAL BIOLOGY: Orienting Stem Cells  

NSDL National Science Digital Library

Access to the article is free, however registration and sign-in are required. Stem cells have the ability to self-renew and to differentiate into a variety of different cell types. However, it is not clear what determines the path taken by any particular stem cell. Discussing recent work with stem cells from the fruit fly testis (Yamashita et al.), Wallenfang and Matunis explain in their Perspective that, at least in the case of these stem cells, the trick is the asymmetric arrangement of the mitotic spindle during cell division. This asymmetric arrangement ensures that as the stem cell divides, one daughter cell remains in the environmental niche of the testis and continues to self-renew, whereas the other daughter cell is edged out of the niche and begins to differentiate.

Matthew R. Wallenfang (University of Pennsylvania;Department of Cell and Developmental Biology); Erika Matunis (The Johns Hopkins Medical Institutions;Department of Cell Biology)

2003-09-12

314

Bioprinting for stem cell research  

PubMed Central

Recently, there has been a growing interest to apply bioprinting techniques to stem cell research. Several bioprinting methods have been developed utilizing acoustics, piezoelectricity, and lasers to deposit living cells onto receiving substrates. Using these technologies, spatially defined gradients of immobilized proteins can be engineered to direct stem cell differentiation into multiple subpopulations of different lineages. Stem cells can also be patterned in a high-throughput manner onto flexible implementation patches for tissue regeneration or onto substrates with the goal of accessing encapsulated stem cell of interest for genomic analysis. Here, we review recent achievements with bioprinting technologies in stem cell research, and identify future challenges and potential applications including tissue engineering and regenerative medicine, wound healing, and genomics. PMID:23260439

Tasoglu, Savas; Demirci, Utkan

2012-01-01

315

Stem Cells behind the Barrier  

PubMed Central

Epidermal stem cells sustain the adult skin for a lifetime through self-renewal and the production of committed progenitors. These stem cells generate progeny that will undergo terminal differentiation leading to the development of a protective epidermal barrier. Whereas the molecular mechanisms that govern epidermal barrier repair and renewal have been extensively studied, pathways controlling stem cell differentiation remain poorly understood. Asymmetric cell divisions, small non-coding RNAs (microRNAs), chromatin remodeling complexes, and multiple differentiation factors tightly control the balance of stem and progenitor cell proliferation and differentiation, and disruption of this balance leads to skin diseases. In this review, we summarize and discuss current advances in our understanding of the mechanisms regulating epidermal stem and progenitor cell differentiation, and explore new relationships for maintenance of skin barrier function. PMID:23812084

Cangkrama, Michael; Ting, Stephen B.; Darido, Charbel

2013-01-01

316

Leaving STEM: STEM Ph.D. Holders in Non-STEM Careers. Issue Brief  

ERIC Educational Resources Information Center

During the last few decades, national, state, and institutional-level initiatives have been implemented to build and expand the science, technology, engineering, and mathematics (STEM) workforce by recruiting and retaining groups of individuals that have been traditionally underrepresented in STEM in higher education. The underlying theory of…

Turk-Bicakci, Lori; Berger, Andrea

2014-01-01

317

The YAP1 homolog-mediated oxidative stress tolerance is crucial for pathogenicity of the necrotrophic fungus Alternaria alternata in citrus.  

PubMed

Citrus brown spot disease is caused by the necrotrophic fungus Alternaria alternata. Its pathogenic capability has been thought to depend exclusively on the production of host-selective ACT toxin. However, circumvention of plant defenses is also likely to be important for the disease process. To investigate the fungal response to host-generated reactive oxygen species (ROS), we cloned and characterized the AaAP1 gene of A. alternata, which encodes a polypeptide resembling yeast YAP1-like transcriptional activators implicated in cellular responses to stress. Expression of the AaAP1 gene in a wild-type strain was primarily induced by H(2)O(2) or ROS-generating oxidants. Using a loss-of-function mutation in the AaAP1 gene, we demonstrated an essential requirement for oxidative tolerance during the host invasion step. Mutants lacking AaAP1 showed increased sensitivity to H(2)O(2) and loss of fungal pathogenicity. The DeltaAaAP1 null mutant did not cause any visible necrotic lesions on wounded or unwounded leaves of citrus cv. Minneola. Compared with the wild type, the null mutant displayed lower catalase, peroxidase, and superoxide dismutase activities. All mutant phenotypes were restored to the wild type in fungal strains expressing a functional copy of AaAP1. Upon exposure to H(2)O(2), the AaAP1::sGFP (synthetic green fluorescent protein) fusion protein became localized in the nucleus. Inoculation of the mutant with NADPH oxidase inhibitors partially restored fungal pathogenicity. Our results highlight the global regulatory role of a YAP1 homolog in response to oxidative stress in A. alternata and provide insights into the critical role of ROS detoxification in the pathogenicity of A. alternata. PMID:19589070

Lin, Ching-Hsuan; Yang, Siwy Ling; Chung, Kuang-Ren

2009-08-01

318

Chilling Stress--The Key Predisposing Factor for Causing Alternaria alternata Infection and Leading to Cotton (Gossypium hirsutum L.) Leaf Senescence  

PubMed Central

Leaf senescence plays a vital role in nutrient recycling and overall capacity to assimilate carbon dioxide. Cotton premature leaf senescence, often accompanied with unexpected short-term low temperature, has been occurring with an increasing frequency in many cotton-growing areas and causes serious reduction in yield and quality of cotton. The key factors for causing and promoting cotton premature leaf senescence are still unclear. In this case, the relationship between the pre-chilling stress and Alternaria alternata infection for causing cotton leaf senescence was investigated under precisely controlled laboratory conditions with four to five leaves stage cotton plants. The results showed short-term chilling stress could cause a certain degree of physiological impairment to cotton leaves, which could be recovered to normal levels in 2–4 days when the chilling stresses were removed. When these chilling stress injured leaves were further inoculated with A. alternata, the pronounced appearance and development of leaf spot disease, and eventually the pronounced symptoms of leaf senescence, occurred on these cotton leaves. The onset of cotton leaf senescence at this condition was also reflected in various physiological indexes such as irreversible increase in malondialdehyde (MDA) content and electrolyte leakage, irreversible decrease in soluble protein content and chlorophyll content, and irreversible damage in leaves' photosynthesis ability. The presented results demonstrated that chilling stress acted as the key predisposing factor for causing A. alternata infection and leading to cotton leaf senescence. It could be expected that the understanding of the key factors causing and promoting cotton leaf senescence would be helpful for taking appropriate management steps to prevent cotton premature leaf senescence. PMID:22558354

Zhao, Jingqing; Li, Sha; Jiang, Tengfei; Liu, Zhi; Zhang, Wenwei; Jian, Guiliang; Qi, Fangjun

2012-01-01

319

STEM Colorado: Planetary Transits  

NSDL National Science Digital Library

This applet demonstrates how astronomers measure the properties of extra-solar planets by detecting planetary transits and eclipses. The applet shows a planet in orbit around a star. A graph plots the total brightness of the star as the planet orbits around it. The user can control the star's radius, the star's temperature, the planet's radius, the orbital radius and the albedo. The user can also see how the spectrum of the illuminated side of the planet, due to both the reflected starlight and the emitted planetary radiation, dependes on wavelength, albedo, and the parameters of the system. This is part of a larger collection of applets by STEM Colorado focused mostly on topics in astronomy.

Mccray, Richard; Koelemay, Andrew

2008-08-30

320

STEM Colorado: Eclipsing Binaries  

NSDL National Science Digital Library

This applet demonstrates how one can infer the diameters and temperature of stars by measuring the brightness variations seen in an eclipsing binary star system. The applet displays binary stars eclipsing each other. The user can control the photospheric temperature and radius of each star, as well as the orbital radius and inclination. The applet also allows the user to simulate the effect of noisy data by setting the random error of measurement as a fraction of the total brightness of both stars. The simulation will continue to calculate the system brightness, averaging its results with the previous trials. This is part of a larger collection of applets by STEM Colorado focused mostly on topics in astronomy.

Mccray, Richard; Koelemay, Andrew

2008-10-22

321

Modular stems in DDH.  

PubMed

The Modulus (Lima-Lto) system has been created on the association of a conical stem and a modular neck in order to address the so called "difficult hip". Modularity can maximize the options for a correct reconstruction in a total hip replacement of the coxofemoral anatomy as well as biomechanics. Modulus should be used in CDH, primary hip arthritis, the sequelae of osteotomies and in each case in which we face a congenital or acquired hip deformity. The Modulus stem has been commonly utilised in association with the Delta cup (Lima-Lto) with the chance to use big diameter heads (32-36 mm) and ceramic on ceramic coupling. Modulus has been used in association with Delta cup since November 2002. 51 patients affected by CDH have been treated. Clinical and radiographic results can be considered very good. The average evaluation based on Merle D'Aubigné schedule is equal to 17.5 with a significant increase in the results with respect to the preoperatory score (with an average score equal to 10). In the light of the above, Modulus should be considered a valuable system to optimize the results of total hip replacement also in those more complex situations with a modified femoral morphology, allowing the restoration of a normal biomechanics in terms of off-set and anteversion with benefit in terms of stability and length of the implant as well as in terms of satisfaction of the patient as far as limb length and ROM are concerned. The association of Modulus with big diameter heads gives a higher guarantee in terms of duration of the implant and restoration of the functionality in young patients with a serious deformity and increased functional demands. PMID:19197896

Benazzo, F; Cuzzocrea, F; Stroppa, S; Ravasi, F; Dalla Pria, P

2007-01-01

322

Types of Stem Cell Transplants for Treating Cancer  

MedlinePLUS

... of stem cells for transplant Types of stem cell transplants for treating cancer In a typical stem ... from your identical twin or triplet Autologous stem cell transplants These stem cells come from you alone. ...

323

Stem cell therapy for osteoporosis.  

PubMed

Osteoporosis is a debilitating disease that affects millions of people worldwide. Current osteoporosis treatments are predominantly bone-resorbing drugs that are associated with several side effects. The use of stem cells for tissue regeneration has raised great hope in various fields of medicine, including musculoskeletal disorders. Stem cell therapy for osteoporosis could potentially reduce the susceptibility of fractures and augment lost mineral density by either increasing the numbers or restoring the function of resident stem cells that can proliferate and differentiate into bone-forming cells. Such osteoporosis therapies can be carried out by exogenous introduction of mesenchymal stem cells (MSCs), typically procured from bone marrow, adipose, and umbilical cord blood tissues or through treatments with drugs or small molecules that recruit endogenous stem cells to osteoporotic sites. The main hurdle with cell-based osteoporosis therapy is the uncertainty of stem cell fate and biodistribution following cell transplantation. Therefore, future advancements will focus on long-term engraftment and differentiation of stem cells at desired bone sites for tangible clinical outcome. PMID:24407712

Antebi, Ben; Pelled, Gadi; Gazit, Dan

2014-03-01

324

Adult Stem and Progenitor Cells  

NASA Astrophysics Data System (ADS)

The discovery of adult stem cells in most adult tissues is the basis of a number of clinical studies that are carried out, with therapeutic use of hematopoietic stem cells as a prime example. Intense scientific debate is still ongoing as to whether adult stem cells may have a greater plasticity than previously thought. Although cells with some features of embryonic stem cells that, among others, express Oct4, Nanog and SSEA1 are isolated from fresh tissue, it is not clear if the greater differentiation potential is acquired during cell culture. Moreover, adult more pluripotent cells do not have all pluripotent characteristics typical for embryonic stem cells. Recently, some elegant studies were published in which adult cells could be completely reprogrammed to embryonic stem cell-like cells by overexpression of some key transcription factors for pluripotency (Oct4, Sox2, Klf4 and c-Myc). It will be interesting for the future to investigate the exact mechanisms underlying this reprogramming and whether similar transcription factor pathways are present and/or can be activated in adult more pluripotent stem cells.

Geraerts, Martine; Verfaillie, Catherine M.

325

GPCRs in Stem Cell Function  

PubMed Central

Many tissues of the body cannot only repair themselves, but also self-renew, a property mainly due to stem cells and the various mechanisms that regulate their behavior. Stem cell biology is a relatively new field. While advances are slowly being realized, stem cells possess huge potential to ameliorate disease and counteract the aging process, causing its speculation as the next panacea. Amidst public pressure to advance rapidly to clinical trials, there is a need to understand the biology of stem cells and to support basic research programs. Without a proper comprehension of how cells and tissues are maintained during the adult life span, clinical trials are bound to fail. This review will cover the basic biology of stem cells, the various types of stem cells, their potential function, and the advantages and disadvantages to their use in medicine. We will next cover the role of G-protein coupled receptors in the regulation of stem cells and their potential in future clinical applications. PMID:23415095

DOZE, VAN A.; PEREZ, DIANNE M.

2013-01-01

326

Paving the road for lung stem cell biology: bronchioalveolar stem cells and other putative distal lung stem cells  

Microsoft Academic Search

New discoveries in stem cell biology are making the biology of solid tissues increasingly complex. Important seminal studies demonstrating the presence of damage-resistant cell populations together with new isolation and characterization techniques suggest that stem cells exist in the adult lung. More detailed in vivo molecular and cellular characterization of bronchioalveolar stem cells (BASCs), other putative lung stem and progenitor

Carla F. Kim

2007-01-01

327

Stem cells in pharmaceutical biotechnology.  

PubMed

Multiple populations of stem cells have been indicated to potentially participate in regeneration of injured organs. Especially, embryonic stem cells (ESC) and recently inducible pluripotent stem cells (iPS) receive a marked attention from scientists and clinicians for regenerative medicine because of their high proliferative and differentiation capacities. Despite that ESC and iPS cells are expected to give rise into multiple regenerative applications when their side effects are overcame during appropriate preparation procedures, in fact their most recent application of human ESC may, however, reside in their use as a tool in drug development and disease modeling. This review focuses on the applications of stem cells in pharmaceutical biotechnology. We discuss possible relevance of pluripotent cell stem populations in developing physiological models for any human tissue cell type useful for pharmacological, metabolic and toxicity evaluation necessary in the earliest steps of drug development. The present models applied for preclinical drug testing consist of primary cells or immortalized cell lines that show limitations in terms of accessibility or relevance to their in vivo counterparts. The availability of renewable human cells with functional similarities to their in vivo counterparts is the first landmark for a new generation of cell-based assays. We discuss the approaches for using stem cells as valuable physiological targets of drug activity which may increase the strength of target validation and efficacy potentially resulting in introducing new safer remedies into clinical trials and the marketplace. Moreover, we discuss the possible applications of stem cells for elucidating mechanisms of disease pathogenesis. The knowledge about the mechanisms governing the development and progression of multitude disorders which would come from the cellular models established based on stem cells, may give rise to new therapeutical strategies for such diseases. All together, the applications of various cell types derived from patient specific pluripotent stem cells may lead to targeted drug and cellular therapies for certain individuals. PMID:21902635

Zuba-Surma, Ewa K; Józkowicz, Alicja; Dulak, Józef

2011-11-01

328

UCLA stem cell scientists discover new airway stem cell:  

Cancer.gov

Researchers at UCLA have identified a new stem cell that participates in the repair of the large airways of the lungs, which play a vital role in protecting the body from infectious agents and toxins in the environment.

329

Stem cells, dot-com.  

PubMed

Direct-to-consumer (DTC) advertising of suspect goods and services has burgeoned because of the Internet. Despite very limited approval for use, DTC stem cell-marketed "treatments" have emerged for an array of conditions, creating global public health and safety risks. However, it remains unclear whether such use of stem cells is subject to drugs or biologics regulations. To address this gap, regulatory agencies should be given clear authority, and the international community should create a framework for appropriate stem cell use. In addition, consumer protection laws should be used to scrutinize providers. PMID:22972840

Liang, Bryan A; Mackey, Tim K

2012-09-12

330

Distal stem features improve the torsional resistance of long-stem cemented revision hip stems: an in vitro biomechanical study.  

PubMed

When proximal bone stock is compromised at revision hip arthroplasty, distal fixation is often relied upon for stability of the femoral component. In such circumstances, torsional forces can result in debonding and loosening. This study compared the torsional behaviour of a cemented, polished and featureless (plain) stem with cemented, polished stems featuring fins or flutes. The finned stem construct was found to be significantly stiffer than the fluted stem. The maximum torque of the finned and fluted stems was significantly higher than the plain stem, with no difference between the finned and fluted stems. Distal stem features may provide a more reliable and greater resistance to torque in polished, cemented revision hip stems. Finned stem features may also increase the stiffness of the construct. PMID:23637260

Holsgrove, Timothy P; Petheram, Timothy G; Miles, Anthony W; Timperley, Andrew J

2013-05-01

331

Generation of induced pluripotent stem cells from neural stem cells  

Microsoft Academic Search

The generation of induced pluripotent stem (iPS) cells from mouse and human somatic cells by expression of defined transcription factors (Oct4, Sox2, c-Myc, Klf4, Nanog and Lin28) is a powerful tool for conducting basic research and investigating the potential of these cells for replacement therapies. In our laboratory, iPS cells have been generated from adult mouse neural stem cells (NSCs)

Jeong Beom Kim; Holm Zaehres; Marcos J Araúzo-Bravo; Hans R Schöler

2009-01-01

332

Targeting Leukemia Stem Cells and Stem Cell Pathways in ALL  

Microsoft Academic Search

\\u000a Growing evidence suggests that haematological malignancies are ­sustained by a critical population of leukemia-initiating\\u000a cells or leukemia stem cells. These cellular populations are likely to be the critical target for eradication of leukemia\\u000a and most likely form the reservoir for relapse and disease resistance. Leukemia stem cells (LSC) have been demonstrated in\\u000a Acute Lymphoblastic Leukemia (ALL), although their origins, identity

Clare Pridans; Brian J. P. Huntly

333

Two-photon imaging of stem cells  

Microsoft Academic Search

A variety of human and animal stem cells (rat and human adult pancreatic stem cells, salivary gland stem cells, dental pulpa stem cells) have been investigated by femtosecond laser 5D two-photon microscopy. Autofluorescence and second harmonic generation have been imaged with submicron spatial resolution, 270 ps temporal resolution, and 10 nm spectral resolution. In particular, NADH and flavoprotein fluorescence was

A. Uchugonova; E. Gorjup; I. Riemann; D. Sauer; K. König

2008-01-01

334

Asymmetric stem cell division: precision for robustness.  

PubMed

Asymmetric cell division (ACD) produces two daughter cells with distinct fates or characteristics. Many adult stem cells use ACD as a means of maintaining stem cell number and thus tissue homeostasis. Here, we review recent progress on ACD, discussing conservation between stem and non-stem cell systems, molecular mechanisms, and the biological meaning of ACD. PMID:23040475

Inaba, Mayu; Yamashita, Yukiko M

2012-10-01

335

28. Embryonic and adult stem cell therapy  

Microsoft Academic Search

Stem cells are characterized by the ability to remain undifferentiated and to self-renew. Embryonic stem cells derived from blastocysts are pluripotent (able to differentiate into many cell types). Adult stem cells, which were traditionally thought to be monopotent multipotent, or tissue restricted, have recently also been shown to have pluripotent properties. Adult bone marrow stem cells have been shown to

Carl T. Henningson; Marisha A. Stanislaus; Alan M. Gewirtz

2003-01-01

336

The STEM Initiative: Constraints and Challenges  

ERIC Educational Resources Information Center

There is considerable national interest in STEM initiatives, but yet there is little discussion concerning what STEM means in terms of a curriculum concept to be applied to school programming. This article focuses on STEM as a curriculum concept. First, STEM programming is discussed in terms of separate subjects, correlated and broad fields…

Herschbach, Dennis R.

2011-01-01

337

Cell Stem Cell Adult SVZ Stem Cells Lie in a Vascular  

E-print Network

Cell Stem Cell Article Adult SVZ Stem Cells Lie in a Vascular Niche: A Quantitative Analysis Susan K. Goderie,1 Badrinath Roysam,3 and Sally Temple1,2,* 1New York Neural Stem Cell Institute within stem cell niches. Here, we examine whether neural stem cells (NSCs) in the adult subventricular

Lin, Gang

338

EMBRYONIC STEM CELLS or INDUCED PLURIPOTENT STEM CELLS? A DNA INTEGRITY PERSPECTIVE  

E-print Network

1 EMBRYONIC STEM CELLS or INDUCED PLURIPOTENT STEM CELLS? A DNA INTEGRITY PERSPECTIVE Qiang Bai Gene Therapy 2013;13(2):93-8" #12;2 ABSTRACT Induced pluripotent stem cells (iPSCs) and embryonic stem cells (ESCs) are two types of pluripotent stem cells that hold great promise for biomedical research

Boyer, Edmond

339

Columbia Stem Cell Initiative Tapping the potential of stem cells for human health  

E-print Network

Faculty Positions in Stem Cell Research at Columbia University Medical Center The Columbia Stem Cell of stem cells for human health. Their research covers all aspects of stem cell research, from basic Professor and Associate Professor level. Applicants' research may focus directly on stem cell biology

Adams, Mark

340

Curr Gene Ther . Author manuscript Embryonic stem cells or induced pluripotent stem cells? A DNA integrity  

E-print Network

Curr Gene Ther . Author manuscript Page /1 7 Embryonic stem cells or induced pluripotent stem cellsPSCs) and embryonic stem cells (ESCs) are two types of pluripotent stem cells that hold great promise for biomedical ; Embryonic Stem Cells ; cytology ; immunology ; Epigenesis, Genetic ; Genomic Instability ; Humans ; Induced

Paris-Sud XI, Université de

341

From stem cells to germ cells and from germ cells to stem cells  

Microsoft Academic Search

Germline and somatic stem cells are distinct types of stem cells that are dedicated to reproduction and somatic tissue regeneration, respectively. Germline stem cells (GSCs), which can self-renew and generate gametes, are unique stem cells in that they are solely dedicated to transmit genetic information from generation to generation. We developed a strategy for the establishment of germline stem cell

Gerald Wulf; Ingrid E. Ehrmann; David Elliott; Ulrich Zechner; Thomas Haaf; Andreas Meinhardt; Hans W. Michelmann; Gerlad Hasenfuss; Kaomei Guan

342

Interpreting stem diameter changes  

NASA Astrophysics Data System (ADS)

Detecting phloem transport in stem diameter changes Teemu Hölttä1, Sanna Sevanto2, Eero Nikinmaa1 1Department of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland 2Department of Physics, P.O. Box 48, FIN-00014 University of Helsinki, Finland Introduction The volume of living cells and xylem conduits vary according to pressures they are subjected to. Our proposition is that the behavior of the inner bark diameter variation which cannot be explained by changes in xylem water status arise from changes in the osmotic concentration of the phloem and cambial growth. Materials and methods Simultaneous xylem and stem diameter measurements were conducted between June 28th to October 4th 2006 in Southern Finland on a 47-year old, 15 meter tall, Scots pine tree (DBH 15 cm) at heights of 1.5 and 10 meters. The difference between the measured inner bark diameter and the inner bark diameter predicted from xylem diameter change with a simple model (assuming there was no change in the osmotic concentration of the phloem) is hypothesized to give the changes in the osmotic concentration of the inner bark. The simple model calculates the radial water exchange between the xylem and phloem driven by the water potential changes in the xylem. Results and Discussion The major signal in the inner bark diameter was the transpiration rate as assumed, but also a signal arising from the change in the osmotic concentration (Fig 1a). The predicted osmotic concentration of the phloem typically increased during the afternoon due to the loading of photosynthesized sugars to the phloem. Inner bark osmotic concentration followed the photosynthesis rate with a 3 and 4 hour time-lag at the top and base, respectively (Fig 1b). The connection between photosynthesis and the predicted change in phloem osmotic concentration was stronger in the upper part of the tree compared to lower part. The changes in the predicted osmotic concentration were not similar every day, indicating that photosynthesized sugars were not always immediately loaded to the phloem (not shown). Figures Fig 1. (a) Measured xylem and inner bark diameter, the inner bark diameter predicted from xylem diameter alone, and the difference between the measured inner bark diameter and the inner bark diameter predicted from xylem diameter. (b) Measured transpiration and photosynthesis rates and the change in osmotic concentration at tree top and bottom predicted by the analysis.

Hölttä, T.; Sevanto, S.; Nikinmaa, E.

2009-12-01

343

25 YEARS OF EPIDERMAL STEM CELLS  

PubMed Central

This is a chronicle of concepts in the field of epidermal stem cell biology and a historic look at their development over time. The last 25 years have seen the evolution of epidermal stem cell science, from first fundamental studies to a sophisticated science. The study of epithelial stem cell biology was aided by the ability to visualize the distribution of stem cells and their progeny through lineage analysis studies. The excellent progress we have made in understanding epidermal stem cell biology is discussed in this article. The challenges we still face in understanding epidermal stem cell include defining molecular markers for stem and progenitor subpopulations, determining the locations and contributions of the different stem cell niches, and mapping regulatory pathways of epidermal stem cell proliferation and differentiation. However, our rapidly evolving understanding of epidermal stem cells has many potential uses that promise to translate into improved patient therapy. PMID:22205306

Ghadially, Ruby

2012-01-01

344

Dental stem cells--characteristics and potential.  

PubMed

Soft dental tissues have been identified as easily accessible sources of multipotent postnatal stem cells. Dental stem cells are mesenchymal stem cells (MSC) capable of differentiating into at least three distinct cell lineages: osteo/odontogenic, adipogenic and neurogenic. They express various markers including those specific for MSC, embryonic stem cells and neural cells. Five different types of dental stem cells have been isolated from mature and immature teeth: dental pulp stem cells, stem cells from exfoliated deciduous teeth, periodontal ligament stem cells, stem cells from apical papilla and dental follicle progenitor cells. Dental stem cells may be used in dental tissue engineering including dental, enamel and periodontal tissue regeneration. They could also be used as a promising tool in potential treatment of neurodegenerative, ischemic and immune diseases. PMID:24446280

Bojic, Sanja; Volarevic, Vladislav; Ljujic, Biljana; Stojkovic, Miodrag

2014-06-01

345

Modeling Stem Cell Induction Processes  

E-print Network

Technology for converting human cells to pluripotent stem cell using induction processes has the potential to revolutionize regenerative medicine. However, the production of these so called iPS cells is still quite inefficient ...

Grácio, Filipe

346

Humboldt River main stem, Nevada  

USGS Publications Warehouse

This data set contains the main stem of the Humboldt River as defined by Humboldt Project personnel of the U.S. Geological Survey Nevada District, 2001. The data set was digitized on screen using digital orthophoto quadrangles from 1994.

Warmath, Eric; Medina, Rose L.

2001-01-01

347

Cell Stem Cell Short Article  

E-print Network

-renewal and reprogramming. INTRODUCTION The transcription factors OCT4, NANOG, and SOX2 are master regulators the requirement of OCT4, SOX2, and NANOG in stem cell function (De Los Angeles et al., 2012), discrepancies

Collins, James J.

348

Framework bolsters stem cell progress.  

PubMed

With many of the leading science nations still stuck in debates on the use of embryonic stem cells, Britain, with a regulatory framework in place, is well-positioned to take the lead. Michael Gross reports. PMID:15296763

Gross, Michael

2004-08-10

349

Stem Cells Promises to Keep?  

NSDL National Science Digital Library

Samantha and her husband Brad have two children, conceived with the help of in vitro fertilization treatments. After viewing a TV program on stem cells and their potential medical uses, Samantha is convinced that they should donate the remaining frozen embryos they have to medical research, an idea Brad strongly objects to. The case teaches about stem cells and their medical applications as well as the ethical dilemmas posed by their use.

Yaich, Lauren E.

2002-01-01

350

The stem cell debate CNN  

NSDL National Science Digital Library

As most of our readers no doubt know, President Bush made a determination on federal funding for embryonic stem cell research in August 2001, agreeing to release federal funds for research involving already existing stem cell lines. Information on this contentious topic is available at CNN's in-depth special, which features articles, analysis, video clips, and message boards devoted to the many aspects of the debate.

2001-01-01

351

Renal Stem Cells and Kidney Regeneration  

Microsoft Academic Search

\\u000a Significant advances have been made in stem cell research over the past decade. A number of non-hematopoietic sources of stem\\u000a cells (or progenitor cells) have been identified including endothelial stem cells and neural stem cells. These discoveries\\u000a have been a major step towards the potential regeneration of organs for clinical applications using stem cells. The worldwide\\u000a shortage of donor kidneys

Takashi Yokoo; Akira Fukui; Kei Matsumoto; Tetsuya Kawamura

352

[Plasticity of tissue stem cells].  

PubMed

In the early stages of embryonic development, cells have the capability of dividing indefinitely and then differentiating into any type of cell in the body. Recent studies have revealed that much of this remarkable developmental potential of stem cells is retained by small populations of cells within most tissues in the adult. Intercellular signals that control the proliferation, differentiation and survival of tissue stem cells in their niches are being identified and include a diverse array of morphogens, cytokines, chemokines and cell adhesion molecules. Adult tissue stem cells, moreover, can also differentiate into developmentally unrelated cell types, such as nerve stem cells into blood cells. Currently, we can only speculate about the mechanisms involved in such dramatic changes in cell fate. For example, the emergence of, say, hematopoietic stem cells from brain neurospheres could involve either transdifferentiation (brain-->blood) or dedifferentiation (brain-->pluripotent cells), or by the actions of rare, but residual pluripotent stem cells. This issue is central to understanding the molecular basis of commitment and lies at the heart of debates about plasticity and the reversibility of developmental restriction. PMID:12053651

Uher, Ferenc; Vas, Virág

2002-05-01

353

Locally induced neural stem cells\\/pluripotent stem cells for in vivo cell replacement therapy  

Microsoft Academic Search

Neural stem cells hold the key to innovative new treatments for age-associated degeneration and traumatic injury to the brain and spinal cord. We hypothesized that the in vivo induced pluripotent stem cells or neural stem cells through \\

Ti-Fei Yuan; Oscar Arias-Carrión

2008-01-01

354

Specialized and shared functions of the histidine kinase- and HOG1 MAP kinase-mediated signaling pathways in Alternaria alternata, a filamentous fungal pathogen of citrus.  

PubMed

Signal transduction pathways are critical for the coordination of complex cellular processes in cells. In Alternaria alternata, a necrotrophic fungal pathogen of citrus, cloning and characterization of a gene coding a Group III histidine kinase (AaHSK1) and the yeast HOG1 ortholog (AaHOG1) showed the two genes to operate, both uniquely and synergistically, in a number of physiological and pathological functions. Systemic loss-of-function genetics in A. alternata revealed that AaHSK1 is a primary regulator for cellular resistance to sugar osmotic stress and for sensitivity to dicarboximide or phenylpyrrole fungicides. These functions were likely modulated by unknown mechanisms rather than solely by the AaHOG1-mediated pathway. AaHOG1, which conferred cellular resistance to salts and oxidative stress, also bypassed AaHSK1, even though deletion of AaHSK1 affected AaHOG1 phosphorylation. Phosphorylation of AaHOG1 was increased when the fungus was treated with osmotic stress, fungicides or H(2)O(2). Fungal mutants impaired in AaHSK1, AaHOG1, AaAP1 (encoding a redox-responsive transcription factor) or AaFUS3 (encoding a MAP kinase) were all hypersensitive to 2-chloro-5-hydroxypyridine (CHP) or 2,3,5-triiodobenzoic acid (TIBA). An AaHOG1::sGFP (synthetic green fluorescent protein) fusion protein became localized in the nucleus in response to H(2)O(2), CHP, TIBA, fungicides, but not glucose. Glucose, however, enhanced AaHOG1 phosphorylation and nuclear localization in the AaHSK1 deficient background. Accumulation of the AaHSK1 gene transcript was negatively regulated by AaHOG1, AaAP1 or AaFUS3. AaHOG1 was necessary for fungal pathogenicity, yet AaHSK1 was completely dispensable for pathogenicity. Our results highlight a dramatic flexibility and uniqueness in the signaling pathways that are involved in responding to diverse environmental stimuli in A. alternata. PMID:20601043

Lin, Ching-Hsuan; Chung, Kuang-Ren

2010-10-01

355

Massachusetts Higher Education STEM Faculty: Partnering in the Transformation of STEM  

E-print Network

Massachusetts Higher Education STEM Faculty: Partnering Organized By: Massachusetts Academy of Sciences Massachusetts Department of Higher Education #12;Massachusetts Higher Education STEM Faculty: Partnering

Riley, Margaret

356

Stem-cell ecology and stem cells in motion  

PubMed Central

This review highlights major scientific developments over the past 50 years or so in concepts related to stem-cell ecology and to stem cells in motion. Many thorough and eloquent reviews have been presented in the last 5 years updating progress in these issues. Some paradigms have been challenged, others validated, or new ones brought to light. In the present review, we will confine our remarks to the historical development of progress. In doing so, we will refrain from a detailed analysis of controversial data, emphasizing instead widely accepted views and some challenging novel ones. PMID:18398055

Scadden, David T.

2008-01-01

357

Stem Cell Transplantation for Neuroprotection in Stroke  

PubMed Central

Stem cell-based therapies for stroke have expanded substantially over the last decade. The diversity of embryonic and adult tissue sources provides researchers with the ability to harvest an ample supply of stem cells. However, the optimal conditions of stem cell use are still being determined. Along this line of the need for optimization studies, we discuss studies that demonstrate effective dose, timing, and route of stem cells. We recognize that stem cell derivations also provide uniquely individual difficulties and limitations in their therapeutic applications. This review will outline the current knowledge, including benefits and challenges, of the many current sources of stem cells for stroke therapy. PMID:24147217

Shinozuka, Kazutaka; Dailey, Travis; Tajiri, Naoki; Ishikawa, Hiroto; Kaneko, Yuji; Borlongan, Cesar V.

2013-01-01

358

[Conservative femoral implants. Short stems].  

PubMed

Uncemented hip replacement matches the best results of classic cemented replacements. With the aim of preserving bone and soft tissue, implants with shorter stems and proximal metaphyseal support have been developed. Likewise, the lack of distal load should avoid cortical diaphyseal remodelling phenomena and the thigh pain of some cylindrical and wedge implants. The resurfacing implant, very popular as a conservative hip replacement in the young adult, has disadvantages associated with the fragility of the neck and with large head metal friction torque. Short stem hip replacement may be a reasonable alternative to classic implants and surface hip replacements. The different designs of conservative short stem implants are analysed, and are classified according to their morphology and biomechanical characteristics. Some medium term series show promising results. PMID:23177948

Valverde-Mordt, C; Valverde-Belda, D

2012-01-01

359

Are cancer stem cells radioresistant?  

PubMed Central

Based on findings that cancer cell clonogens exhibit stem cell features, it has been suggested that cancer stem-like cells are relatively radioresistant owing to different intrinsic and extrinsic factors, including quiescence, activated radiation response mechanisms (e.g., enhanced DNA repair, upregulated cell cycle control mechanisms and increased free-radical scavengers) and a surrounding microenvironment that enhances cell survival mechanisms (e.g., hypoxia and interaction with stromal elements). However, these radiosensitivity features are probably dynamic in nature and come into play at different times during the course of chemo/radiotherapy. Therefore, different molecularly targeted radiosensitization strategies may be needed at different stages of therapy. This article describes potential sensitization approaches based on the dynamics and changing properties of cancer stem-like cells during therapy. PMID:21062156

Hittelman, Walter N; Liao, Yong; Wang, Li; Milas, Luka

2011-01-01

360

Stem Cells and Calcium Signaling  

PubMed Central

The increasing interest in stem cell research is linked to the promise of developing treatments for many lifethreatening, debilitating diseases, and for cell replacement therapies. However, performing these therapeutic innovations with safety will only be possible when an accurate knowledge about the molecular signals that promote the desired cell fate is reached. Among these signals are transient changes in intracellular Ca2+ concentration [Ca2+]i. Acting as an intracellular messenger, Ca2+ has a key role in cell signaling pathways in various differentiation stages of stem cells. The aim of this chapter is to present a broad overview of various moments in which Ca2+-mediated signaling is essential for the maintenance of stem cells and for promoting their development and differentiation, also focusing on their therapeutic potential. PMID:22453975

Tonelli, Fernanda M.P.; Santos, Anderson K.; Gomes, Dawidson A.; da Silva, Saulo L.; Gomes, Katia N.; Ladeira, Luiz O.

2014-01-01

361

p53 in stem cells  

PubMed Central

p53 is well known as a “guardian of the genome” for differentiated cells, in which it induces cell cycle arrest and cell death after DNA damage and thus contributes to the maintenance of genomic stability. In addition to this tumor suppressor function for differentiated cells, p53 also plays an important role in stem cells. In this cell type, p53 not only ensures genomic integrity after genotoxic insults but also controls their proliferation and differentiation. Additionally, p53 provides an effective barrier for the generation of pluripotent stem cell-like cells from terminally differentiated cells. In this review, we summarize our current knowledge about p53 activities in embryonic, adult and induced pluripotent stem cells. PMID:21949570

Solozobova, Valeriya; Blattner, Christine

2011-01-01

362

Science: Embryos and Stem Cells  

NSDL National Science Digital Library

It's quite easy to stay abreast of all the developments within the world of embryos and stem cell research with this handy site created and maintained by staff members at the Guardian newspaper. On their page, visitors can read news reports from the frontlines of scientific research in these areas, and also check out the latest posts from the weblogs they maintain on these matters. Further down the page, visitors will find a selection of specialized reports on both stem cell research and the manipulation and transformation of embryos. Visitors can also sign up to receive an RSS feed and even learn about related subjects, including genetics and biotechnology.

2008-06-04

363

Reconstructing the stem cell debate.  

PubMed

Human embryonic stem cells have been a major topic in science, medicine, and religion since their discovery in 1998. However, due to the complex discourse and rhetoric of scientific language, debate has remained within the professional realm via "expert bioethics." Using the tenets of pragmatism, the author examines the need to move the debate to society as a whole and disentangle the stem cell debate from the ideologies of the human cloning and abortion debates. Opening this issue to a societal debate will advance societal growth, resulting in informed decisions on moral issues, funding, or regulation associated with hES cell research. PMID:12755109

Sitko, Bradley J

2002-01-01

364

Stem-and-Leaf Plots  

NSDL National Science Digital Library

This lesson is designed to introduce students to stem-and-leaf plots as a graphical way to represent a data set. The lesson also reviews measures of central tendency with directions for finding mean, median, and mode are given. This lesson provides links to discussions and activities related to stem-and-leaf plots as well as suggested ways to integrate them into the lesson. Finally, the lesson provides links to follow-up lessons designed for use in succession with the current one.

Shodor

2012-04-02

365

Making STEM Fun: How to Organize a STEM Camp  

ERIC Educational Resources Information Center

The work from the University of Central Florida's STEM summer camp (sponsored by Workforce Central Florida) is shared. The camps targeted low-SES schools with a high percentage of students on free and reduced lunch as well as high percentages of students with. Students were given preassessments and postassessments to gauge their knowledge of and…

Davis, Kimberly E. Bryant; Hardin, Stacey E.

2013-01-01

366

Notions about human stem cells. [Stem cell proliferation  

Microsoft Academic Search

Precise characterization of the structure of hemopoiesis in man and its quantitation is required for an understanding of hemopoietic regulation and its response to toxic agents, during and after chemotherapy and radiotherapy, in the course of various diseases, and in individuals exposed to agents known to be or which may be toxic to the bone marrow. Knowledge of stem cell

E. P. Cronkite; L. E. Feinendegen

1975-01-01

367

Stem cell differentiation: Sticky mechanical memory  

NASA Astrophysics Data System (ADS)

Physical cues from the extracellular environment influence the lineage commitment of stem cells. Now, experiments on human mesenchymal stem cells cultured on photodegradable hydrogels show that the cells' fate can also be determined by past physical environments.

Eyckmans, Jeroen; Chen, Christopher S.

2014-06-01

368

Dyskeratosis congenita and limbal stem cell deficiency  

Microsoft Academic Search

In light of the latest developments in the field of molecular hematology, we herein discuss the reported cases that have presented dyskeratosis congenita as one of the inherited stem cell diseases causing limbal stem cell deficiency.

Deniz Aslan; Rustu Fikret Akata

2010-01-01

369

Editor's Corner: STEM Beyond the Classroom  

NSDL National Science Digital Library

One of our most important tasks as science educators is to encourage students to consider careers in science, technology, engineering, and mathematics (STEM). So, how do we encourage more students to consider STEM careers? It is a multilayered problem, bu

Metz, Steve

2009-12-01

370

7 CFR 29.6037 - Stem.  

Code of Federal Regulations, 2012 CFR

... Agriculture 2 2012-01-01 2012-01-01 false Stem. 29.6037 Section 29.6037 Agriculture Regulations... TOBACCO INSPECTION Standards Definitions § 29.6037 Stem. The midrib or large central vein of a tobacco...

2012-01-01

371

Plant Structure--Leaves, Stems, and Roots  

NSDL National Science Digital Library

Page one consists of a full color illustration of an idealized plant, showing various leaf, stem and root features. Page two illustrates various adaptations of plant flowers, leaves and stems. All illustrations are accompanied by explanations of the structures' functions.

2000-01-01

372

30 CFR 75.1322 - Stemming boreholes  

Code of Federal Regulations, 2010 CFR

...tamped to fill the entire cross sectional area of the borehole. (c) Stemming material shall contact the explosive cartridge nearest the collar of the borehole. (d) Each borehole 4 or more feet deep shall be stemmed for at...

2010-07-01

373

Enabling Stem Cell Research and Development  

E-print Network

to an optimal global solution for stem cell R&D. Relying onstem cell materials in existence, in order to identify where new solutionssolutions. Membership may be defined simply as institutions that are “engaged in stem cell

Saha, Krishanu; Graff, Gregory; Winickoff, David

2007-01-01

374

Control of the Embryonic Stem Cell State  

E-print Network

Embryonic stem cells and induced pluripotent stem cells hold great promise for regenerative medicine. These cells can be propagated in culture in an undifferentiated state but can be induced to differentiate into specialized ...

Young, Richard A.

375

7 CFR 29.6037 - Stem.  

Code of Federal Regulations, 2010 CFR

... Agriculture 2 2010-01-01 2010-01-01 false Stem. 29.6037 Section 29.6037 Agriculture Regulations... TOBACCO INSPECTION Standards Definitions § 29.6037 Stem. The midrib or large central vein of a tobacco...

2010-01-01

376

7 CFR 29.6037 - Stem.  

Code of Federal Regulations, 2011 CFR

... Agriculture 2 2011-01-01 2011-01-01 false Stem. 29.6037 Section 29.6037 Agriculture Regulations... TOBACCO INSPECTION Standards Definitions § 29.6037 Stem. The midrib or large central vein of a tobacco...

2011-01-01

377

Stem Cell Reports Quality Metrics for Stem Cell-Derived Cardiac Myocytes  

E-print Network

Stem Cell Reports Article Quality Metrics for Stem Cell-Derived Cardiac Myocytes Sean P. Sheehy,1, provided the original author and source are credited. SUMMARY Advances in stem cell manufacturing methods have made it possible to produce stem cell-derived cardiac myocytes at industrial scales for in vitro

378

Stem Cell Reports CRIPTO/GRP78 Signaling Maintains Fetal and Adult Mammary Stem Cells  

E-print Network

Stem Cell Reports Report CRIPTO/GRP78 Signaling Maintains Fetal and Adult Mammary Stem Cells Ex cell behavior. Here, we identify CRIPTO and its cell- surface receptor GRP78 as regulators of stem cell differentiation and reduces self-renewal of mammary stem cell-enriched populations cultured ex vivo. By contrast

Wahl, Geoffrey M.

379

Stem Cell Rev . Author manuscript Human bone marrow mesenchymal stem cells: a systematic reappraisal  

E-print Network

Stem Cell Rev . Author manuscript Page /1 11 Human bone marrow mesenchymal stem cells: a systematic (acronym for Adult mesenchymal stem cells engineering for connective tissue disorders. From the bench Mesenchymal Stem Cell (MSC) biological properties and repair capacity. Part of Genostem activity has been

Paris-Sud XI, Université de

380

College Students' Conceptions of Stem Cells, Stem Cell Research, and Cloning  

ERIC Educational Resources Information Center

In this study, we examined 96 undergraduate non-science majors' conceptions of stem cells, stem cell research, and cloning. This study was performed at a large, Midwest, research extensive university. Participants in the study were asked to answer 23 questions relating to stem cells, stem cell research, and cloning in an on-line assessment before…

Concannon, James P.; Siegel, Marcelle A.; Halverson, Kristy; Freyermuth, Sharyn

2010-01-01

381

College Students' Conceptions of Stem Cells, Stem Cell Research, and Cloning  

Microsoft Academic Search

In this study, we examined 96 undergraduate non-science majors' conceptions of stem cells, stem cell research, and cloning. This study was performed at a large, Midwest, research extensive university. Participants in the study were asked to answer 23 questions relating to stem cells, stem cell research, and cloning in an on-line assessment before and after instruction. Two goals of the

James P. Concannon; Marcelle A. Siegel; Kristy Halverson; Sharyn Freyermuth

2010-01-01

382

Spatial Organization of Embryonic Stem Cell Responsiveness to Autocrine Gp130 Ligands Reveals an Autoregulatory Stem  

E-print Network

Spatial Organization of Embryonic Stem Cell Responsiveness to Autocrine Gp130 Ligands Reveals, Ontario, Canada Key Words. Autocrine signaling · Embryonic stem cell · Niche · Self-renewal · Stem cell-location-independent processes control- ling cell fate by analyzing the spatial organization of embryonic stem cells (ESCs) using

Zandstra, Peter W.

383

Bio-engineering of stem/progenitor cells Blood stem cell products  

E-print Network

Bio-engineering of stem/progenitor cells Blood stem cell products: Toward sustainable benchmarks expansion of umbilical cord blood (UCB) derived hematopoietic stem and progenitor cells (HSPCs) should stem cell derived products that fulfill our current best known criteria of clinical relevance

Zandstra, Peter W.

384

Results of Curing Some Diseases by Stem Cell Transplantation at Stem Cell R&D Laboratory  

Microsoft Academic Search

Stem cell therapy in curing dangerous diseases usually is main target of many researches about stem cells. In the world, researching and applying stem cells to cure diseases got some great achievements while there is a few in Viet Nam. In recently years, Laboratory of Stem cell R&D, University of Science, VNU HCM city carried out some researches about pre-

Phan Kim Ngoc; Pham Van Phuc; Viet Nam

2010-01-01

385

College Students’ Conceptions of Stem Cells, Stem Cell Research, and Cloning  

Microsoft Academic Search

In this study, we examined 96 undergraduate non-science majors’ conceptions of stem cells, stem cell research, and cloning. This study was performed at a large, Midwest, research extensive university. Participants in the study were asked to answer 23 questions relating to stem cells, stem cell research, and cloning in an on-line assessment before and after instruction. Two goals of the

James P. Concannon; Marcelle A. Siegel; Kristy Halverson; Sharyn Freyermuth

2010-01-01

386

Media presentation and public understanding of stem cells and stem cell research in Hungary  

Microsoft Academic Search

This paper reports on a research project which examined media coverage and audience perceptions of stem cells and stem cell research in Hungary, using focus groups and a media analysis. A background study was also conducted on the Hungarian legal, social and political situation linked to stem cell research, treatment and storage. Our data show how stem cell research\\/treatments were

Lilla Vicsek; Júlia Gergely

2011-01-01

387

Stem Cells of Mammalian Brain: Biology of the Stem Cells in vivoand in vitro  

Microsoft Academic Search

Stem cells are totipotent cells of the blastocyst (embryonal stem cells) and multipotent germinative cells of ento-, ecto-, and mesoderm that give rise to all tissues during embryogenesis. The stem cells have high proliferation activity and an unlimited capacity for self-production by symmetrical mitosis. Asymmetrical mitosis of the stem cells generates daughter cells (“progenitor cells”) with unlimited proliferation potential. During

I. V. Viktorov

2001-01-01

388

Stem cells and tooth tissue engineering  

Microsoft Academic Search

The notion that teeth contain stem cells is based on the well-known repairing ability of dentin after injury. Dental stem\\u000a cells have been isolated according to their anatomical locations, colony-forming ability, expression of stem cell markers,\\u000a and regeneration of pulp\\/dentin structures in vivo. These dental-derived stem cells are currently under increasing investigation\\u000a as sources for tooth regeneration and repair. Further

Amanda H.-H. Yen; Paul T. Sharpe

2008-01-01

389

Stem cell and precursor cell therapy  

Microsoft Academic Search

Strategies for cell replacement therapy have been guided by the success in the hematopoietic stem cell field. In this review,\\u000a we discuss the basis of this success and examine whether this stem cell transplant model can be replicated in other systems\\u000a where stem cell therapy is being evaluated. We conclude that identifying the most primitive stem cell and using it

Jingli Cai; Mahendra S. Rao

2002-01-01

390

New therapeutics targeting colon cancer stem cells  

Microsoft Academic Search

The recent identification of tumor-initiating colorectal cancer (CRC) stem cells in the pathogenesis of CRC has provided a\\u000a potential target for novel therapeutics. Many details about CRC stem cells, however, remain poorly understood. Several potential\\u000a markers of CRC stem cells have been proposed, including CD133, CD44, and, recently, Lgr5. Attention also has been drawn to\\u000a control of stem cell self-renewal,

Arun Thenappan; Ying Li; Kirti Shetty; Lynt Johnson; E. P. Reddy; Lopa Mishra

2009-01-01

391

Head and Neck Cancer Stem Cells  

Microsoft Academic Search

Most cancers contain a small sub-population of cells that are endowed with self-renewal, multipotency, and a unique potential for tumor initiation. These properties are considered hallmarks of cancer stem cells. Here, we provide an overview of the field of cancer stem cells with a focus on head and neck cancers. Cancer stem cells are located in the invasive fronts of

S. Krishnamurthy; J. E. Nör

2012-01-01

392

Developmental Cell Sox2+ Stem Cells Contribute  

E-print Network

as a marker for the dental epithelial stem cells will facilitate further studies on their lineage segregationDevelopmental Cell Article Sox2+ Stem Cells Contribute to All Epithelial Lineages of the Tooth via and Department of Stem Cell and Regenerative Biology, Harvard University and Harvard Medical School, 7 Divinity

Klein, Ophir

393

Epigenetic regulation of aging stem cells  

Microsoft Academic Search

The function of adult tissue-specific stem cells declines with age, which may contribute to the physiological decline in tissue homeostasis and the increased risk of neoplasm during aging. Old stem cells can be ‘rejuvenated’ by environmental stimuli in some cases, raising the possibility that a subset of age-dependent stem cell changes is regulated by reversible mechanisms. Epigenetic regulators are good

E A Pollina; A Brunet

2011-01-01

394

Generalized Potential of Adult Neural Stem Cells  

Microsoft Academic Search

The differentiation potential of stem cells in tissues of the adult has been thought to be limited to cell lineages present in the organ from which they were derived, but there is evidence that some stem cells may have a broader differentiation repertoire. We show here that neural stem cells from the adult mouse brain can contribute to the formation

Diana L. Clarke; Clas B. Johansson; Johannes Wilbertz; Biborka Veress; Erik Nilsson; Helena Karlström; Urban Lendahl; Jonas Frisén

2000-01-01

395

Embryonic Stem Cells Cell Signalling Course  

E-print Network

Embryonic Stem Cells Cell Signalling Course Ceské Budjovice January 2013 #12;Pluripotent (stem) cells (Embryonic, Adult, Induced,...?) Promise for biomedicine ·Replacement therapy ·Drug development(s) of differentiation ·Symmetric/asymmetric division ? ? ? ? #12;Where can we find the origins of stem cell research

South Bohemia, University of

396

Embryonic Stem Cells Cell Signalling Course  

E-print Network

Embryonic Stem Cells Cell Signalling Course Ceské Budjovice November 2013 #12;Pluripotent (stem) cells (Embryonic, Adult, Induced,...?) Promise for biomedicine ·Replacement therapy ·Drug development(s) of differentiation ·Symmetric/asymmetric division ? ? ? ? #12;Where can we find the origins of stem cell research

South Bohemia, University of

397

Description Soybean stem borer is the  

E-print Network

Description Soybean stem borer is the common name of a small, long-horned beetle that attacks soybeans. The adult beetleis pale gray in color and is about 3/8 inch long with antennae that are longer The soybean stem borer overwinters as a larva in the base of hollowed-out, girdled stems. Larvae pupate

Mukhtar, Saqib

398

Learning about Cancer by Studying Stem Cells  

MedlinePLUS

... About Cancer by Studying Stem Cells Inside Life Science View All Articles | Inside Life Science Home Page Learning About Cancer by Studying Stem ... Once Upon a Stem Cell This Inside Life Science article also appears on LiveScience . Learn about related ...

399

Considerations for Teaching Integrated STEM Education  

Microsoft Academic Search

Quality Science, Technology, Engineering, and Mathematics (STEM) education is vital for the future success of students. Integrated STEM education is one way to make learning more connected and relevant for students. There is a need for further research and discussion on the knowledge, experiences, and background that teachers need to effectively teach integrated STEM education. A support, teaching, efficacy, and

Micah Stohlmann; Tamara J. Moore; Gillian H. Roehrig

2012-01-01

400

Incorporating Ethics into K-12 STEM Education  

E-print Network

Incorporating Ethics into K-12 STEM Education: An Introduction Richard A. Burgess, M.A. Texas Tech for Engineering Ethics (NIEE) to incorporate Ethics into all STEM education and outreach efforts. · In this module be integrated into a Project Based Learning (PBL) context. #12;Why Include Ethics in STEM Education? · A great

Gelfond, Michael

401

Cell Stem Cell The Systematic Production  

E-print Network

Cell Stem Cell Review The Systematic Production of Cells for Cell Therapies Daniel C. Kirouac1 10.1016/j.stem.2008.09.001 Stem cells have emerged as the starting material of choice for bioprocesses to produce cells and tissues to treat degenerative, genetic, and immunological disease

Zandstra, Peter W.

402

Human stem cell ethics: beyond the embryo.  

PubMed

Human embryonic stem cell research has elicited powerful debates about the morality of destroying human embryos. However, there are important ethical issues related to stem cell research that are unrelated to embryo destruction. These include particular issues involving different types of cells used, the procurement of such cells, in vivo use of stem cells, intellectual property, and conflicts of interest. PMID:18522846

Sugarman, Jeremy

2008-06-01

403

Cell Stem Cell Alternative Induced Pluripotent  

E-print Network

-disease- relevant area of stem cell research. We agree that criteria and standards are important to allow for crossCell Stem Cell Letter Alternative Induced Pluripotent Stem Cell Characterization Criteria Cell Facility, SickKids Research Institute, University of Toronto, Toronto, Ontario M5G 1L7, Canada 2

Zandstra, Peter W.

404

*Institute for Stem Cell Research, GSF --National  

E-print Network

*Institute for Stem Cell Research, GSF -- National Research Center for Environment and Health neural stem cells. THE CELL BIOLOGY OF NEUROGENESIS Magdalena Götz* and Wieland B. Huttner Abstract | During the development of the mammalian central nervous system, neural stem cells and their derivative

Cai, Long

405

--Taking STem Cell SCienCe from  

E-print Network

associate professor of biomedical engineering and stem cell researcher, says that basic research the frontiers of biomedical engineering and stem cell research: associate professor Treena livingston arinzeh Medicine, dedi- cated to creating technologies to translate basic stem cell research into practical

Bieber, Michael

406

Patenting Human Genes and Stem Cells  

Microsoft Academic Search

Cell lines and genetically modified single cell organisms have been considered patentable subjects for the last two decades. However, despite the technical patentability of genes and stem cell lines, social and legal controversy concerning their 'ownership' has surrounded stem cell research in recent years. Some granted patents on stem cells with extremely broad claims are casting a shadow over the

Enca Martin-Rendon; Derek J. Blake

2007-01-01

407

Autophagy prevents irradiation injury and maintains stemness through decreasing ROS generation in mesenchymal stem cells  

PubMed Central

Stem cells were characterized by their stemness: self-renewal and pluripotency. Mesenchymal stem cells (MSCs) are a unique type of adult stem cells that have been proven to be involved in tissue repair, immunoloregulation and tumorigenesis. Irradiation is a well-known factor that leads to functional obstacle in stem cells. However, the mechanism of stemness maintenance in human MSCs exposed to irradiation remains unknown. We demonstrated that irradiation could induce reactive oxygen species (ROS) accumulation that resulted in DNA damage and stemness injury in MSCs. Autophagy induced by starvation or rapamycin can reduce ROS accumulation-associated DNA damage and maintain stemness in MSCs. Further, inhibition of autophagy leads to augment of ROS accumulation and DNA damage, which results in the loss of stemness in MSCs. Our results indicate that autophagy may have an important role in protecting stemness of MSCs from irradiation injury. PMID:24113178

Hou, J; Han, Z-p; Jing, Y-y; Yang, X; Zhang, S-s; Sun, K; Hao, C; Meng, Y; Yu, F-h; Liu, X-q; Shi, Y-f; Wu, M-c; Zhang, L; Wei, L-x

2013-01-01

408

The Top STEM Degree Producers  

ERIC Educational Resources Information Center

This article presents a list of the top Science, Technology, Engineering, and Mathematics (STEM) degree producers in the U.S. This list is broken down into seven categories: (1) Total Minority Research/Scholarship and Other Doctoral: Mathematics and Statistics; (2) Total Minority Bachelors: Biological and Biomedical Sciences; (3) Total Minority…

Diverse: Issues in Higher Education, 2012

2012-01-01

409

Iatrogenic Limbal Stem Cell Deficiency  

Microsoft Academic Search

Although little has been written about iatrogenic limbal stem cell deficiency, patients with this disorder are probably more common than the literature might suggest. It is important to recognize this disorder as a limbal deficiency, since standard medical therapies will not address its etiology. The sequelae of this condition include stromal scarring and significant loss of vision. Fortunately, phacoemulsification has

Gary S. Schwartz; Edward J. Holland

410

STEM Education: Proceed with Caution  

ERIC Educational Resources Information Center

The STEM (science, technology, engineering and mathematics) movement has developed from a non-educational rationale. Although some think it may enliven the delivery of maths and science in classrooms, the social and economic rationales are those that have initiated this movement. Spurred on by the global financial crisis, it is hoped that…

Williams, P. John

2011-01-01

411

Gene and Stem Cell Therapy  

Microsoft Academic Search

Gene and stem cell therapy are being developed as novel treatments for cystic fibrosis (CF). In gene therapy, the therapeutic nucleic acid is delivered to terminally differentiated epithelial cells in the airways. While technically less demanding, this approach has the drawback that therapy must be continually re-administered because of target cell turnover. Direct airway administration is also faced with powerful

A. Boyd

2006-01-01

412

Stem cell therapy and gene transfer for regeneration  

Microsoft Academic Search

The committed stem and progenitor cells have been recently isolated from various adult tissues, including hematopoietic stem cell, neural stem cell, mesenchymal stem cell and endothelial progenitor cell. These adult stem cells have several advantages as compared with embryonic stem cells as their practical therapeutic application for tissue regeneration. In this review, we discuss the promising gene therapy application of

T Asahara; C Kalka; J M Isner

2000-01-01

413

Expression of the antiapoptotic baculovirus p35 gene in tomato blocks programmed cell death and provides broad-spectrum resistance to disease  

PubMed Central

The sphinganine analog mycotoxin, AAL-toxin, induces a death process in plant and animal cells that shows apoptotic morphology. In nature, the AAL-toxin is the primary determinant of the Alternaria stem canker disease of tomato, thus linking apoptosis to this disease caused by Alternaria alternata f. sp. lycopersici. The product of the baculovirus p35 gene is a specific inhibitor of a class of cysteine proteases termed caspases, and naturally functions in infected insects. Transgenic tomato plants bearing the p35 gene were protected against AAL-toxin-induced death and pathogen infection. Resistance to the toxin and pathogen co-segregated with the expression of the p35 gene through the T3 generation, as did resistance to A. alternata, Colletotrichum coccodes, and Pseudomonas syringae pv. tomato. The p35 gene, stably transformed into tomato roots by Agrobacterium rhizogenes, protected roots against a 30-fold greater concentration of AAL-toxin than control roots tolerated. Transgenic expression of a p35 binding site mutant (DQMD to DRIL), inactive against animal caspases-3, did not protect against AAL-toxin. These results indicate that plants possess a protease with substrate-site specificity that is functionally equivalent to certain animal caspases. A biological conclusion is that diverse plant pathogens co-opt apoptosis during infection, and that transgenic modification of pathways regulating programmed cell death in plants is a potential strategy for engineering broad-spectrum disease resistance in plants. PMID:12403830

Lincoln, James E.; Richael, Craig; Overduin, Bert; Smith, Kathy; Bostock, Richard; Gilchrist, David G.

2002-01-01

414

Isolation and characterization of rhizosphere bacteria for the biocontrol of the damping-off disease of tomatoes in Tunisia.  

PubMed

Fluorescent Pseudomonas spp., isolated from tomato and pepper plants rhizosphere soil, was evaluated in vitro as a potential antagonist of fungal pathogens. Pseudomonas strains were tested against the causal agents of tomatoes damping-off (Sclerotinia sclerotiorum), root rot (Fusarium solani), and causal agents of stem canker and leaf blight (Alternaria alternata). For this purpose, dual culture antagonism assays were carried out on 25% tryptic soy agar, King B medium and potato dextrose agar to determine the effect of the strains on mycelial growth of the pathogens. In addition, strains were screened for their ability to produce exoenzymes and siderophores. All the strains significantly inhibited Alternaria alternata, particularly in 25% TSA medium. Antagonistic effect on Sclerotinia sclerotiorum and Fusarium solani was greater on King B medium. Protease was produced by 30% of the strains, but no strain produced cellulase or chitinase. Finally, the selected Pseudomonas strain, Psf5, was evaluated on tomato seedling development and as a potential candidate for controlling tomato damping-off caused by Sclerotinia sclerotiorum, under growth chamber conditions. In vivo studies resulted in significant increases in plant stand as well as in root dry weight. Psf5 was able to establish and survive in tomato plants rhizosphere after 40days following the planting of bacterized seeds. PMID:24296079

Hammami, Inés; Ben Hsouna, Anis; Hamdi, Naceur; Gdoura, Radhouane; Triki, Mohamed Ali

2013-01-01

415

Conversion of adult mouse unipotent germline stem cells into pluripotent stem cells  

Microsoft Academic Search

Germline stem cells (GSCs), often called spermatogonial stem cells, are unipotent stem cells that can give rise only to gametes. Under defined culture conditions, unipotent GSCs can be converted into pluripotent stem cells, termed as germline-derived pluripotent stem (gPS) cells. gPS cells can be differentiated into cells forming all three germ layers and germ cells. In this study, we describe

Kinarm Ko; Marcos J Araúzo-Bravo; Julee Kim; Martin Stehling; Hans R Schöler

2010-01-01

416

Neural stem cell engineering: directed differentiation of adult and embryonic stem cells into neurons Matthew J. Robertson1  

E-print Network

Neural stem cell engineering: directed differentiation of adult and embryonic stem cells Adult and embryonic stem cells 5. Embryonic stem cells 5.1. Expanding and culturing embryonic stem cells potential of embryonic stem cells in animal models 5.5.1. ES cell-derived dopaminergic cells 5.5.2. ES cell

Schaffer, David V.

417

Saving Superman: Ethics and Stem Cell Research  

NSDL National Science Digital Library

This case explores the political and ethical issues associated with stem cell research. Students read the case describing Christopher Reeve’s accident and injuries and his advocacy for stem cell research along with background readings on stem cells and the ethics of stem cell research. They are then assigned to one of four stakeholder groups and asked to develop a position on whether or not the U.S. Senate should expand stem cell research with a focus on the ethics underlying the issue.  They present their positions in class in a simulated public hearing.

Post, Doug M.; Knutson, Doug

2006-01-01

418

Embryonic stem cell patents and human dignity.  

PubMed

This article examines the assertion that human embryonic stem cells patents are immoral because they violate human dignity. After analyzing the concept of human dignity and its role in bioethics debates, this article argues that patents on human embryos or totipotent embryonic stem cells violate human dignity, but that patents on pluripotent or multipotent stem cells do not. Since patents on pluripotent or multipotent stem cells may still threaten human dignity by encouraging people to treat embryos as property, patent agencies should carefully monitor and control these patents to ensure that patents are not inadvertently awarded on embryos or totipotent stem cells. PMID:17922198

Resnik, David B

2007-09-01

419

Perspectives on human stem cell research.  

PubMed

Human stem cell research draws not only scientists' but the public's attention. Human stem cell research is considered to be able to identify the mechanism of human development and change the paradigm of medical practices. However, there are heated ethical and legal debates about human stem cell research. The core issue is that of human dignity and human life. Some prefer human adult stem cell research or iPS cell research, others hES cell research. We do not need to exclude any type of stem cell research because each has its own merits and issues, and they can facilitate the scientific revolution when working together. PMID:19384875

Jung, Kyu Won

2009-09-01

420

ADULT STEM CELLS AND THEIR NICHES  

PubMed Central

Stem cells participate in dynamic physiologic systems that dictate the outcome of developmental events and organismal stress, Since these cells are fundamental to tissue maintenance and repair, the signals they receive play a critical role in the integrity of the organism. Much work has focused on stem cell identification and the molecular pathways involved in their regulation. Yet, we understand little about how these pathways achieve physiologically responsive stem cell functions. This chapter will review the state of our understanding of stem cells in the context of their microenvironment regarding the relation between stem cell niche dysfunction, carcinogenesis and aging. PMID:21222205

Ferraro, Francesca; Celso, Cristina Lo; Scadden, David

2014-01-01

421

Stem Cells for Neurovascular Repair in Stroke  

PubMed Central

Stem cells exert therapeutic effects against ischemic stroke via transplantation of exogenous stem cells or stimulation of endogenous stem cells within the neurogenic niches of subventricular zone and subgranular zone, or recruited from the bone marrow through peripheral circulation. In this paper, we review the different sources of stem cells that have been tested in animal models of stroke. In addition, we discuss specific mechanisms of action, in particular neurovascular repair by endothelial progenitor cells, as key translational research for advancing the clinical applications of stem cells for ischemic stroke. PMID:24077523

Shinozuka, Kazutaka; Dailey, Travis; Tajiri, Naoki; Ishikawa, Hiroto; Kim, Dae Won; Pabon, Mibel; Acosta, Sandra; Kaneko, Yuji; Borlongan, Cesar V

2013-01-01

422

Challenges for heart disease stem cell therapy  

PubMed Central

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. The use of stem cells to improve recovery of the injured heart after myocardial infarction (MI) is an important emerging therapeutic strategy. However, recent reviews of clinical trials of stem cell therapy for MI and ischemic heart disease recovery report that less than half of the trials found only small improvements in cardiac function. In clinical trials, bone marrow, peripheral blood, or umbilical cord blood cells were used as the source of stem cells delivered by intracoronary infusion. Some trials administered only a stem cell mobilizing agent that recruits endogenous sources of stem cells. Important challenges to improve the effectiveness of stem cell therapy for CVD include: (1) improved identification, recruitment, and expansion of autologous stem cells; (2) identification of mobilizing and homing agents that increase recruitment; and (3) development of strategies to improve stem cell survival and engraftment of both endogenous and exogenous sources of stem cells. This review is an overview of stem cell therapy for CVD and discusses the challenges these three areas present for maximum optimization of the efficacy of stem cell therapy for heart disease, and new strategies in progress. PMID:22399855

Hoover-Plow, Jane; Gong, Yanqing

2012-01-01

423

Stem cells news update: a personal perspective.  

PubMed

This article is a follow-up to a previous Commentary published in 2011. It updates some of the events mentioned in that Commentary and continues with more interesting and exciting news on stem cell research and the emerging field of Regenerative Medicine. Some of the news includes: 1) the 2012 Nobel Prize for Medicine awarded to John B. Gurdon and Shinya Yamanaka; 2) the cloning of human embryonic stem cells; 3) the continued search for truly pluripotent adult stem cells via in vitro and in vivo protocols; 4) the breakthrough in organ replacements; 5) the global stem cell race; 6) the global stem cell cryo-preservation business; 7) the worldwide stem cell donor registries, and 8) the issue of government regulation on stem cell therapy. PMID:24778557

Wong, Sc

2013-12-01

424

Stem Cells News Update: A Personal Perspective  

PubMed Central

This article is a follow-up to a previous Commentary published in 2011. It updates some of the events mentioned in that Commentary and continues with more interesting and exciting news on stem cell research and the emerging field of Regenerative Medicine. Some of the news includes: 1) the 2012 Nobel Prize for Medicine awarded to John B. Gurdon and Shinya Yamanaka; 2) the cloning of human embryonic stem cells; 3) the continued search for truly pluripotent adult stem cells via in vitro and in vivo protocols; 4) the breakthrough in organ replacements; 5) the global stem cell race; 6) the global stem cell cryo-preservation business; 7) the worldwide stem cell donor registries, and 8) the issue of government regulation on stem cell therapy. PMID:24778557

Wong, SC

2013-01-01

425

Encapsulated stem cells for cancer therapy.  

PubMed

Stem cells have inherent tumor?trophic migratory properties and can serve as vehicles for delivering effective, targeted therapy to isolated tumors and metastatic disease, making them promising anti?cancer agents. Encapsulation of therapeutically engineered stem cells in hydrogels has been utilized to provide a physical barrier to protect the cells from hostile extrinsic factors and significantly improve the therapeutic efficacy of transplanted stem cells in different models of cancer. This review aims to discuss the potential of different stem cell types for cancer therapy, various engineered stem cell based therapies for cancer, stem cell encapsulation process and provide an in depth overview of current applications of therapeutic stem cell encapsulation in the highly malignant brain tumor, glioblastoma multiforme (GBM), as well as the prospects for their clinical translation. PMID:23507920

Shah, Khalid

2013-01-01

426

Epidermal Stem Cells and Their Epigenetic Regulation  

PubMed Central

Stem cells play an essential role in embryonic development, cell differentiation and tissue regeneration. Tissue homeostasis in adults is maintained by adult stem cells resident in the niches of different tissues. As one kind of adult stem cell, epidermal stem cells have the potential to generate diversified types of progeny cells in the skin. Although its biology is still largely unclarified, epidermal stem cells are widely used in stem cell research and regenerative medicine given its easy accessibility and pluripotency. Despite the same genome, cells within an organism have different fates due to the epigenetic regulation of gene expression. In this review, we will briefly discuss the current understanding of epigenetic modulation in epidermal stem cells. PMID:23999591

Shen, Qi; Jin, Hongchuan; Wang, Xian

2013-01-01

427

Stem cells and repair of lung injuries  

PubMed Central

Fueled by the promise of regenerative medicine, currently there is unprecedented interest in stem cells. Furthermore, there have been revolutionary, but somewhat controversial, advances in our understanding of stem cell biology. Stem cells likely play key roles in the repair of diverse lung injuries. However, due to very low rates of cellular proliferation in vivo in the normal steady state, cellular and architectural complexity of the respiratory tract, and the lack of an intensive research effort, lung stem cells remain poorly understood compared to those in other major organ systems. In the present review, we concisely explore the conceptual framework of stem cell biology and recent advances pertinent to the lungs. We illustrate lung diseases in which manipulation of stem cells may be physiologically significant and highlight the challenges facing stem cell-related therapy in the lung. PMID:15285789

Neuringer, Isabel P; Randell, Scott H

2004-01-01

428

Encapsulated stem cells for cancer therapy  

PubMed Central

Stem cells have inherent tumor?trophic migratory properties and can serve as vehicles for delivering effective, targeted therapy to isolated tumors and metastatic disease, making them promising anti?cancer agents. Encapsulation of therapeutically engineered stem cells in hydrogels has been utilized to provide a physical barrier to protect the cells from hostile extrinsic factors and significantly improve the therapeutic efficacy of transplanted stem cells in different models of cancer. This review aims to discuss the potential of different stem cell types for cancer therapy, various engineered stem cell based therapies for cancer, stem cell encapsulation process and provide an in depth overview of current applications of therapeutic stem cell encapsulation in the highly malignant brain tumor, glioblastoma multiforme (GBM), as well as the prospects for their clinical translation. PMID:23507920

2013-01-01

429

Endometrial stem cells in regenerative medicine  

PubMed Central

First described in 2004, endometrial stem cells (EnSCs) are adult stem cells isolated from the endometrial tissue. EnSCs comprise of a population of epithelial stem cells, mesenchymal stem cells, and side population stem cells. When secreted in the menstrual blood, they are termed menstrual stem cells or endometrial regenerative cells. Mounting evidence suggests that EnSCs can be utilized in regenerative medicine. EnSCs can be used as immuno-modulatory agents to attenuate inflammation, are implicated in angiogenesis and vascularization during tissue regeneration, and can also be reprogrammed into induced pluripotent stem cells. Furthermore, EnSCs can be used in tissue engineering applications and there are several clinical trials currently in place to ascertain the therapeutic potential of EnSCs. This review highlights the progress made in EnSC research, describing their mesodermal, ectodermal, and endodermal potentials both in vitro and in vivo. PMID:25097665

2014-01-01

430

A stem cell for stem cells in murine haematopoiesis  

Microsoft Academic Search

Mature erythrocytes and granulocytes have limited lifespans, do not replicate and must therefore be replenished constantly. They are derived from pluripotent stem cells (PSCs) which are capable of self-renewal1. The numbers and properties of PSCs can be inferred in part from studies of their progeny. Such studies have depended largely on highly artificial experimental systems, involving such procedures as X-ray

D. I. Burton; J. D. Ansell; R. A. Gray; H. S. Micklem

1982-01-01

431

Retroviral Expression in Embryonic Stem Cells and Hematopoietic Stem Cells  

PubMed Central

Achieving long-term retroviral expression in primary cells has been problematic. De novo DNA methylation of infecting proviruses has been proposed as a major cause of this transcriptional repression. Here we report the development of a mouse stem cell virus (MSCV) long terminal repeat-based retroviral vector that is expressed in both embryonic stem (ES) cells and hematopoietic stem (HS) cells. Infected HS cells and their differentiated descendants maintained long-term and stable retroviral expression after serial adoptive transfers. In addition, retrovirally infected ES cells showed detectable expression level of the green fluorescent protein (GFP). Moreover, GFP expression of integrated proviruses was maintained after in vitro differentiation of infected ES cells. Long-term passage of infected ES cells resulted in methylation-mediated silencing, while short-term expression was methylation independent. Tissues of transgenic animals, which we derived from ES cells carrying the MSCV-based provirus, did not express GFP. However, treatment with the demethylating agent 5-azadeoxycytidine reactivated the silent provirus, demonstrating that DNA methylation is involved in the maintenance of retroviral repression. Our results indicate that retroviral expression in ES cells is repressed by methylation-dependent as well as methylation-independent mechanisms. PMID:11003639

Cherry, Sara R.; Biniszkiewicz, D.; van Parijs, L.; Baltimore, D.; Jaenisch, R.

2000-01-01

432

Cancer Stem Cells Converted from Pluripotent Stem Cells and the Cancerous Niche  

PubMed Central

Nowadays, the cancer stem cells are considered to be significantly responsible for growth, metastasis, invasion and recurrence of all cancer. Cancer stem cells are typically characterized by continuous proliferation and self-renewal as well as by differentiation potential, while stem cells are considered to differentiate into tissue- specific phenotype of mature cells under the influence of micro-environment. Cancer stem cells should be traced to the stem cells under the influence of a micro-environment, which induces malignant tumors. In this review, we propose this micro-environment as a ‘cancerous niche’ and discuss its importance on the formation and maintenance of cancer stem cells with the recent experimental results to establish cancer stem cell models from induced pluripotent stem cells. These models of cancer stem cell will provide the great advantages in cancer research and its therapeutic applications in the future. PMID:25075155

Kasai, T; Chen, L; Mizutani, AZ; Kudoh, T; Murakami, H; Fu, L; Seno, M

2014-01-01

433

Polarity in Stem Cell Division: Asymmetric Stem Cell Division in Tissue Homeostasis  

PubMed Central

Many adult stem cells divide asymmetrically to balance self-renewal and differentiation, thereby maintaining tissue homeostasis. Asymmetric stem cell divisions depend on asymmetric cell architecture (i.e., cell polarity) within the cell and/or the cellular environment. In particular, as residents of the tissues they sustain, stem cells are inevitably placed in the context of the tissue architecture. Indeed, many stem cells are polarized within their microenvironment, or the stem cell niche, and their asymmetric division relies on their relationship with the microenvironment. Here, we review asymmetric stem cell divisions in the context of the stem cell niche with a focus on Drosophila germ line stem cells, where the nature of niche-dependent asymmetric stem cell division is well characterized. PMID:20182603

Yamashita, Yukiko M.; Yuan, Hebao; Cheng, Jun; Hunt, Alan J.

2010-01-01

434

Informal STEM Education in Antarctica  

NASA Astrophysics Data System (ADS)

Tourism in Antarctica has increased dramatically with tens of thousands of tourists visiting the White Continent each year. Tourism cruises to Antarctica offer a unique educational experience for lay people through informal science-technology-engineering-mathematics (STEM) education. Passengers attend numerous scientific lectures that cover topics such as the geology of Antarctica, plate tectonics, glaciology, and climate change. Furthermore, tourists experience the geology and glaciology first hand during shore excursions. Currently, the grand challenges facing our global society are closely connected to the Earth sciences. Issues such as energy, climate change, water security, and natural hazards, are consistently on the legislative docket of policymakers around the world. However, the majority of the world’s population is uninformed about the role Earth sciences play in their everyday lives. Tourism in Antarctica provides opportunities for informal STEM learning and, as a result, tourists leave with a better understanding and greater appreciation for both Antarctica and Earth sciences.

Chell, K.

2010-12-01

435

STEM CELLS FOR TOOTH ENGINEERING  

Microsoft Academic Search

Tooth development results from sequential and reciprocal interactions between the oral epithelium and the underlying neural crest-derived mesenchyme. The generation of dental structures and\\/or entire teeth in the laboratory depends upon the manipulation of stem cells and requires a synergy of all cellular and molecular events that finally lead to the formation of tooth-specific hard tissues, dentin and enamel. Although

G. Bluteau; H. U. Luder; C. De Bari; T. A. Mitsiadis; Aberdeen AB

2008-01-01

436

Epithelial stem cells in teeth  

Microsoft Academic Search

Many tissues and organs maintain a process known as homeostasis, in which cells are replenished as they die as a result of\\u000a apoptosis or injury. The continuously growing mouse incisors are an excellent model for studying the molecular mechanisms\\u000a of cell homeostasis, renewal, and repair. We elucidated these mechanisms in mouse incisors by detecting adult stem cells and\\u000a analyzing the

H. Harada; T. Mitsuyasu; T. Toyono; K. Toyoshima

2002-01-01

437

Storage of Adipose Stem Cells  

Microsoft Academic Search

\\u000a Adipose-derived stem cells (ADSCs) are becoming the cells of choice for an increasing number of clinical trials, and they\\u000a promise to be in the next decade the preferential cell type used in cell therapies. Here we describe how they can be isolated\\u000a from adipose tissue, prepared for storage, and eventually conserved in liquid nitrogen, waiting for future cell therapy applications.

Giorgio Bronz; Gianni Soldati

438

STEM Colorado: Simplified Planetary Transits  

NSDL National Science Digital Library

This applet demonstrates how astronomers measure the properties of extra-solar planets by detecting planetary transits and eclipses. The applet shows a planet in orbit around a star. A graph plots the total brightness of the star as the planet orbits around it. The user can control the star's radius, the star's temperature, the planet's radius, the orbital radius and the albedo. This is part of a larger collection of applets by STEM Colorado focused mostly on topics in astronomy.

Mccray, Richard; Koelemay, Andrew

2008-10-22

439

Cardiac Stem and Progenitor Cells  

Microsoft Academic Search

\\u000a Since the early days of cardiovascular biology, it has been believed that mammalian adult cardiomyocytes exit from the cell\\u000a cycle soon after birth, with the total number of cardiomyocytes being pre-determined. Recently, the identification of resident\\u000a cardiac stem\\/progenitor cells by several independent laboratories has challenged this long-held paradigm and has provoked\\u000a an exponential increase in the number of investigations. As

Ronglih Liao; Regina L. Sohn

440

STEM Colorado: Software Applet Page  

NSDL National Science Digital Library

The STEM Software applet page offers Java laboratory applets for the introductory astronomy teacher. These applets illustrate: the communication with extraterrestrial civilizations, radiative transfer, why the setting sun is red and the sky is blue, a random walk in two dimensions, binary star orbits, extra-solar planets, and the Doppler Shift. These applets provide a step-by-step instructional guide for students on how to use the various applets in a laboratory format.

Mccray, Richard; Koelemay, Andrew

2004-11-17

441

Elimination of Cancer Stem Cells  

Microsoft Academic Search

\\u000a The acceptance of the Cancer Stem Cell (CSC) concept has revolutionized all aspects of our understanding of cancer biology,\\u000a from the cellular origin of cancer to its growth and expansion, shedding new light into the interrelations of all the cellular\\u000a components of the tumour and their role in its progression. From the therapeutic point of view, the existence of CSCs

A. Sagrera; J. Pérez-Losada; M. Pérez-Caro; R. Jiménez; I. Sánchez-García; C. Cobaleda

442

Tumor Stem Cells and Metastasis  

Microsoft Academic Search

\\u000a The last decade has seen the emergence of a shift in paradigm in the therapeutic strategies to target cancer. This is based\\u000a on the existence of a small reservoir of cells within the tumor mass that exhibits the capacity for self-renewal, as well\\u000a as undergo differentiation to give rise to phenotypically heterogeneous progeny with limited proliferative potential. These\\u000a stem-like cells

Jaclyn Y. Hung

443

Salivary Gland Cancer Stem Cells  

PubMed Central

Emerging evidence suggests the existence of a tumorigenic population of cancer cells that demonstrate stem cell-like properties such as self-renewal and multipotency. These cells, termed cancer stem cells (CSC), are able to both initiate and maintain tumor formation and progression. Studies have shown that CSC are resistant to traditional chemotherapy treatments preventing complete eradication of the tumor cell population. Following treatment, CSC are able to re-initiate tumor growth leading to patient relapse. Salivary gland cancers are relatively rare but constitute a highly significant public health issue due to the lack of effective treatments. In particular, patients with mucoepidermoid carcinoma or adenoid cystic carcinoma, the two most common salivary malignancies, have low long-term survival rates due to the lack of response to current therapies. Considering the role of CSC in resistance to therapy in other tumor types, it is possible that this unique sub-population of cells is involved in resistance of salivary gland tumors to treatment. Characterization of CSC can lead to better understanding of the pathobiology of salivary gland malignancies as well as to the development of more effective therapies. Here, we make a brief overview of the state-of-the-science in salivary gland cancer, and discuss possible implications of the cancer stem cell hypothesis to the treatment of salivary gland malignancies. PMID:23810400

Adams, April; Warner, Kristy; Nor, Jacques E.

2013-01-01

444

Stem cells and nuclear reprogramming.  

PubMed

Derivation of human embryonic stem (ES) cells from preimplantation embryos ten years ago raised great hopes that they may be an excellent source of cells for cell replacement therapy. However, serious ethical concerns and the risk of immune rejection of allotransplanted cells have hindered the translation of ES cell-based therapies into the clinic. In an attempt to circumvent these barriers, a number of methods have been developed for converting adult somatic cells into a pluripotent state from which ethically acceptable patient-specific mature cells of interest could be derived. These efforts, backed by advances in elucidating the molecular basis of pluripotency, have culminated in successful reprogramming of fibroblasts into ES cell-like cells, termed induced pluripotent stem (iPS) cells, by ectopic expression of only a handful of "stemness" factors. iPS cells possess morphological, molecular and developmental features of conventional blastocyst-derived ES cells and have the potential to serve as a source of therapeutic cells for customized tissue repair, gene therapy, drug discovery, toxicological testing and for studying the molecular basis of human disease. The goal of this review is to provide the current state-of-the-art in this very exciting and dynamic field and to discuss barriers that remain to be removed before the therapeutic potential of iPS cells can be fully realized. PMID:18465442

Saric, Tomo; Hescheler, Juergen

2008-01-01

445

TOPICAL REVIEW Stem cells in bone tissue engineering  

Microsoft Academic Search

Bone tissue engineering has been one of the most promising areas of research, providing a potential clinical application to cure bone defects. Recently, various stem cells including embryonic stem cells (ESCs), bone marrow-derived mesenchymal stem cells (BM-MSCs), umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), adipose tissue-derived stem cells (ADSCs), muscle-derived stem cells (MDSCs) and dental pulp stem cells (DPSCs) have

Jeong Min Seong; Byung-Chul Kim; Jae-Hong Park; Il Keun Kwon; Anathathios Mantalaris; Yu-Shik Hwang

2010-01-01

446

Pluripotent stem cell-derived neural stem cells: From basic research to applications  

PubMed Central

Basic research on pluripotent stem cells is designed to enhance understanding of embryogenesis, whereas applied research is designed to develop novel therapies and prevent diseases. Attainment of these goals has been enhanced by the establishment of embryonic stem cell lines, the technological development of genomic reprogramming to generate induced-pluripotent stem cells, and improvements in vitro techniques to manipulate stem cells. This review summarizes the techniques required to generate neural cells from pluripotent stem cells. In particular, this review describes current research applications of a simple neural differentiation method, the neural stem sphere method, which we developed.

Otsu, Masahiro; Nakayama, Takashi; Inoue, Nobuo

2014-01-01

447

The mitochondrial contribution to stem cell biology.  

PubMed

The distribution and functions of mitochondria in stem cells have not been examined, yet the contributions of these organelles to stem cell viability and differentiation must be vitally important in view of their critical roles in all other cell types. A key role for mitochondria in stem cells is indicated by reports that they translocate in the oocyte during fertilisation to cluster around the pronuclei and can remain in a perinuclear pattern during embryo development. This clustering appears to be essential for normal embryonic development. Because embryonic stem cells are derived from fertilised oocytes, and eventually can differentiate into 'adult' stem cells, it was hypothesised that mitochondrial perinuclear clustering persists through preimplantation embryo development into the stem cells, and that this localisation is indicative of stem cell pluripotency. Further, it was predicted that mitochondrial activity, as measured by respiration and adenosine triphosphate (ATP) content, would correlate with the degree of perinuclear clustering. It was also predicted that these morphological and metabolic measurements could serve as indicators of 'stemness.' This article reviews the distribution and metabolism of mitochondria in a model stem cell line and how this information is related to passage number, differentiation and/or senescence. In addition, it describes mitochondrial DNA deletions in oocytes and embryos that could adversely affect stem cell performance. PMID:17147931

Bavister, Barry D

2006-01-01

448

A comparison study in the proteomic signatures of multipotent germline stem cells, embryonic stem cells, and germline stem cells  

Microsoft Academic Search

Germline stem (GS) cells can only differentiate into germline cells, while multipotent germ stem (mGS) cells, like embryonic stem (ES) cells, can differentiate into various somatic cells and tissues. The proteomic profiles in GS and mGS cells were compared by two-dimensional gel electrophoresis. Ten down-regulated and 16 up-regulated proteins were differentially expressed in mGS cells in comparison to GS cells,

Hajime Kurosaki; Yasuhiro Kazuki; Masaharu Hiratsuka; Toshiaki Inoue; Yasuhisa Matsui; Chi Chiu Wang; Mito Kanatsu-Shinohara; Takashi Shinohara; Tosifusa Toda; Mitsuo Oshimura

2007-01-01

449

Seeing stems everywhere: position-independent identification of stem morphemes.  

PubMed

There is broad consensus that printed complex words are identified on the basis of their constituent morphemes. This fact raises the issue of how the word identification system codes for morpheme position, hence allowing it to distinguish between words like overhang and hangover, and to recognize that preheat is a word, whereas heatpre is not. Recent data have shown that suffixes are identified as morphemes only when they occur at the end of letter strings (Crepaldi, Rastle, & Davis, 2010, "Morphemes in Their Place: Evidence for Position-Specific Identification of Suffixes," Memory & Cognition, 38, 312-321), which supports the general proposal that the word identification system is sensitive to morpheme positional constraints. This proposal leads to the prediction that the identification of free stems should occur in a position-independent fashion, given that free stems can occur anywhere within complex words (e.g., overdress and dresser). In Experiment 1, we show that the rejection time of transposed-constituent pseudocompounds (e.g., moonhoney) is longer than that of matched control nonwords (e.g., moonbasin), suggesting that honey and moon are identified within moonhoney, and that these morpheme representations activate the representation for the word honeymoon. In Experiments 2 and 3, we demonstrate that the masked presentation of transposed-constituent pseudocompounds (e.g., moonhoney) facilitates the identification of compound words (honeymoon). In contrast, monomorphemic control pairs do not produce a similar pattern (i.e., rickmave did not prime maverick), indicating that the effect for moonhoney pairs is genuinely morphological in nature. These results demonstrate that stem representations differ from affix representations in terms of their positional constraints, providing a challenge to all existing theories of morphological processing. PMID:22905908

Crepaldi, Davide; Rastle, Kathleen; Davis, Colin J; Lupker, Stephen J

2013-04-01

450

Two-photon imaging of stem cells  

NASA Astrophysics Data System (ADS)

A variety of human and animal stem cells (rat and human adult pancreatic stem cells, salivary gland stem cells, dental pulpa stem cells) have been investigated by femtosecond laser 5D two-photon microscopy. Autofluorescence and second harmonic generation have been imaged with submicron spatial resolution, 270 ps temporal resolution, and 10 nm spectral resolution. In particular, NADH and flavoprotein fluorescence was detected in stem cells. Major emission peaks at 460nm and 530nm with typical mean fluorescence lifetimes of 1.8 ns and 2.0 ns, respectively, were measured using time-correlated single photon counting and spectral imaging. Differentiated stem cells produced the extracellular matrix protein collagen which was detected by SHG signals at 435 nm.

Uchugonova, A.; Gorjup, E.; Riemann, I.; Sauer, D.; König, K.

2008-02-01

451

Muscle stem cells at a glance  

PubMed Central

ABSTRACT Muscle stem cells facilitate the long-term regenerative capacity of skeletal muscle. This self-renewing population of satellite cells has only recently been defined through genetic and transplantation experiments. Although muscle stem cells remain in a dormant quiescent state in uninjured muscle, they are poised to activate and produce committed progeny. Unlike committed myogenic progenitor cells, the self-renewal capacity gives muscle stem cells the ability to engraft as satellite cells and capitulate long-term regeneration. Similar to other adult stem cells, understanding the molecular regulation of muscle stem cells has significant implications towards the development of pharmacological or cell-based therapies for muscle disorders. This Cell Science at a Glance article and accompanying poster will review satellite cell characteristics and therapeutic potential, and provide an overview of the muscle stem cell hallmarks: quiescence, self-renewal and commitment. PMID:25300792

Wang, Yu Xin; Dumont, Nicolas A.; Rudnicki, Michael A.

2014-01-01

452

History and perspective of stem cell research.  

PubMed

Several types of stem cell have been discovered from germ cells, the embryo, fetus and adult. Each of these has promised to revolutionize the future of regenerative medicine through the provision of cell-replacement therapies to treat a variety of debilitating diseases. Stem cell research is politically charged, receives considerable media coverage, raises many ethical and religious debates and generates a great deal of public interest. The tremendous versatility of embryonic stem cells versus the unprecedented reports describing adult stem cell plasticity have ignited debates as to the choice of one cell type over another for future application. However, the biology of these mysterious cells have yet to be understood and a lot more basic research is needed before new therapies using stem-cell-differentiated derivatives can be applied. Stem cell research opens-up the new field of 'cell-based therapies' and, as such, several safety measures have also to be evaluated. PMID:15582541

Bongso, Ariff; Richards, Mark

2004-12-01

453

Stem cell tracking with optically active nanoparticles  

PubMed Central

Stem-cell-based therapies hold promise and potential to address many unmet clinical needs. Cell tracking with modern imaging modalities offers insight into the underlying biological process of the stem-cell-based therapies, with the goal to reveal cell survival, migration, homing, engraftment, differentiation, and functions. Adaptability, sensitivity, resolution, and non-invasiveness have contributed to the longstanding use of optical imaging for stem cell tracking and analysis. To identify transplanted stem cells from the host tissue, optically active probes are usually used to label stem cells before the administration. In comparison to the traditional fluorescent probes like fluorescent proteins and dyes, nanoparticle-based probes are advantageous in terms of the photo-stabilities and minimal changes to the cell phenotype. The main focus here is to overview the recent development of optically active nanoparticles for stem cells tracking. The related optical imaging modalities include fluorescence imaging, photoacoustic imaging, Raman and surface enhanced Raman spectroscopy imaging. PMID:23638335

Gao, Yu; Cui, Yan; Chan, Jerry KY; Xu, Chenjie

2013-01-01

454

EMBRYONIC STEM CELLS/INDUCED PLURIPOTENT STEM CELLS Nanog Regulates Proliferation During Early Fish Development  

E-print Network

in the neuronal lineage of established OE: neural stem cells, which express the transcription factor Sox2; Mash1, Neurogenesis, Olfactory epithelium, Nasal cavity, Stem cell, Apoptosis, Cre recombinase, Fgf8, Foxg1, Sox2, Pax

DeSalle, Rob

455

Normal and neoplastic non-stem cells can spontaneously convert to a stem-like state  

E-print Network

Current models of stem cell biology assume that normal and neoplastic stem cells reside at the apices of hierarchies and differentiate into nonstem progeny in a unidirectional manner. Here we identify a subpopulation of ...

Su, Ying

456

Dental pulp stem cells in regenerative dentistry  

Microsoft Academic Search

Stem cells constitute the source of differentiated cells for the generation of tissues during development, and for regeneration\\u000a of tissues that are diseased or injured postnatally. In recent years, stem cell research has grown exponentially owing to\\u000a the recognition that stem cell-based therapies have the potential to improve the life of patients with conditions that span\\u000a from Alzheimer’s disease to

Luciano Casagrande; Mabel M. Cordeiro; Silvia A. Nör; Jacques E. Nör

2011-01-01

457

Stem cell therapy in ischemic heart disease.  

PubMed

Coronary artery disease (CAD) remains the leading cause of death in the Western world. The high impact of its main sequelae, acute myocardial infarction and congestive heart failure (CHF), on the quality of life of patients and the cost of health care drives the search for new therapies. The recent finding that stem cells contribute to neovascularization and possibly improve cardiac function after myocardial infarction makes stem cell therapy the most highly active research area in cardiology. Although the concept of stem cell therapy may revolutionize heart failure treatment, several obstacles need to be addressed. To name a few: 1) Which patient population should be considered for stem cell therapy? 2) What type of stem cell should be used? 3) What is the best route for cell delivery? 4) What is the optimum number of cells that should be used to achieve functional effects? 5) Is stem cell therapy safer and more effective than conventional therapies? The published studies vary significantly in design, making it difficult to draw conclusions on the efficacy of this treatment. For example, different models of ischemia, species of donors and recipients, techniques of cell delivery, cell types, cell numbers and timing of the experiments have been used. However, these studies highlight the landmark concept that stem cell therapy may play a major role in treating cardiovascular diseases in the near future. It should be noted that stem cell therapy is not limited to the treatment of ischemic cardiac disease. Non-ischemic cardiomyopathy, peripheral vascular disease, and aging may be treated by stem cells. Stem cells could be used as vehicle for gene therapy and eliminate the use of viral vectors. Finally, stem cell therapy may be combined with pharmacological, surgical, and interventional therapy to improve outcome. Here we attempt a systematic overview of the science of stem cells and their effects when transplanted into ischemic myocardium. PMID:14647535

Sunkomat, Julia N E; Gaballa, Mohamed A

2003-01-01

458

Pluripotency of male germline stem cells  

Microsoft Academic Search

The ethical issues and public concerns regarding the use of embryonic stem (ES) cells in human therapy have motivated considerable\\u000a research into the generation of pluripotent stem cell lines from non-embryonic sources. Numerous reports have shown that pluripotent\\u000a cells can be generated and derived from germline stem cells (GSCs) in mouse and human testes during in vitro cultivation. The gene

Sungtae Kim; Juan Carlos Izpisua Belmonte

459

Hemopoietic stem cells: Sources and applications  

Microsoft Academic Search

Classically hemopoietic stem cells to be used for transplantation or autologous reinfusion have been harvested from the bone\\u000a marrow which has remained the major source of stem cells for allogeneic transplantation. However, pluripotent stem cells also\\u000a circulate in peripheral blood under physiological conditions and can be “mobilized” to appearin very large numbers in peripheral blood by treatment with cytotoxic chemotherapy,

Dae-Sik Hong; H. Joachim Deeg

1994-01-01

460

Towards predictive models of stem cell fate  

Microsoft Academic Search

Quantitative approaches are essential for the advancement of strategies to manipulate stem cells or their derivatives for\\u000a therapeutic applications. Predictive models of stem cell systems would provide the means to pose and validate non-intuitive\\u000a hypotheses and could thus serve as an important tool for discerning underlying regulatory mechanisms governing stem cell fate\\u000a decisions. In this paper we review the development

Sowmya Viswanathan; Peter W. Zandstra

2003-01-01

461

A glossary for stem-cell biology  

Microsoft Academic Search

Stem-cell biology is in a phase of dynamic expansion and is forming connections with a broad range of basic and applied disciplines. The field is simultaneously exposed to public and political scrutiny. A common language in the stem-cell community is an important tool for coherent exposition to these diverse audiences, not least because certain terms in the stem-cell vocabulary are

Austin Smith

2006-01-01

462

Transdifferentiation of Stem Cells: A Critical View  

Microsoft Academic Search

\\u000a Recently a large amount of new data on the plasticity of stem cells of various lineages have emerged, providing new perspectives\\u000a especially for the therapeutic application of adult stem cells. Previously unknown possibilities of cell differentiation beyond\\u000a the known commitment of a given stem cell have been described using keywords such as “blood to liver,” or “bone to brain.”\\u000a Controversies

Ina Gruh; Ulrich Martin

2009-01-01

463

Pluripotent stem cells and their niches  

Microsoft Academic Search

The ability of stem cells to self-renew and to replace mature cells is fundamental to ontogeny and tissue regeneration. Stem\\u000a cells of the adult organism can be categorized as mono-, bi-, or multipotent, based on the number of mature cell types to\\u000a which they can give rise. In contrast, pluripotent stem cells of the early embryo have the ability to

M. William Lensch; Laurence Daheron; Thorsten M. Schlaeger

2006-01-01

464

Embryonic Stem Cell Patents and Human Dignity  

Microsoft Academic Search

This article examines the assertion that human embryonic stem cells patents are immoral because they violate human dignity.\\u000a After analyzing the concept of human dignity and its role in bioethics debates, this article argues that patents on human\\u000a embryos or totipotent embryonic stem cells violate human dignity, but that patents on pluripotent or multipotent stem cells\\u000a do not. Since patents

David B. Resnik

2007-01-01

465

Stem cell banking: between traceability and identifiability  

Microsoft Academic Search

Stem cell banks are increasingly seen as an essential resource of biological materials for both basic and translational research.\\u000a Stem cell banks support transnational access to quality-controlled and ethically sourced stem cell lines from different origins\\u000a and of varying grades. According to the Organisation for Economic Co-operation and Development, advances in regenerative medicine\\u000a are leading to the development of a

Bartha M Knoppers; Rosario Isasi

2010-01-01

466

STEM Focus in Innoventure Competition Theme  

SciTech Connect

This report documents the inclusion of the STEM focus in the annual competition theme for the Innoventure youth project. The STEM concepts have always played a part in the selection of the theme. However, this year, STEM is intentionally mentioned in the description of the theme to emphasize the importance of these concepts. This work is a part of the National Security Preparedness Project (NSPP), being performed under a Department of Energy (DOE)/National Nuclear Security Administration (NNSA) grant.

None

2010-03-31

467

Engineering microenvironments to control stem cell fate and function  

E-print Network

), StemBook, ed. The Stem Cell Research Community, StemBook, doi/10.3824/stembook.1.5.1, httpEngineering microenvironments to control stem cell fate and function Shawdee Eshghi and David V . . . . . . . . . . . . . 3 2.2. Sequential factors to program stem cell differentiation

Schaffer, David V.

468

Cell Stem Cell Stage-Specific Differences in the  

E-print Network

Cell Stem Cell Article Stage-Specific Differences in the Requirements for Germline Stem CellDepartment of Biochemistry, Institute for Stem Cell and Regenerative Medicine, University of Washington tissues in the animal kingdom depend on stem cell populations. Embryonic stem cells are considered

Hay, Bruce A.

469

Cell Stem Cell Wnts as Self-Renewal Factors  

E-print Network

Cell Stem Cell Previews Wnts as Self-Renewal Factors: Mammary Stem Cells and Beyond Esther M, Burnaby, British Columbia V5A 1S6, Canada 2Hubrecht Institute for Developmental Biology and Stem Cell.clevers@hubrecht.eu DOI 10.1016/j.stem.2010.05.004 Adult stem cells hold great promise for regenerative medicine, yet

Verheyen, Esther M.

470

Stemming Cancer: Functional Genomics of Cancer Stem Cells in Solid Tumors  

Microsoft Academic Search

Cancer stem cells (CSCs) were discovered about 15 years ago in hematopoietic cancers. Subsequently, cancer stem cells were\\u000a discovered in various solid tumors. Based on parallels with normal stem cells, a developmental process of cancer stem cells\\u000a follows paths of organized, hierarchical structure of cells with different degrees of maturity. While some investigators have\\u000a reported particular markers as identification of cancer

C. R. A. Regenbrecht; H. Lehrach; J. Adjaye

2008-01-01

471

College Students’ Conceptions of Stem Cells, Stem Cell Research, and Cloning  

Microsoft Academic Search

In this study, we examined 96 undergraduate non-science majors’ conceptions of stem cells, stem cell research, and cloning.\\u000a This study was performed at a large, Midwest, research extensive university. Participants in the study were asked to answer\\u000a 23 questions relating to stem cells, stem cell research, and cloning in an on-line assessment before and after instruction.\\u000a Two goals of the

James P. Concannon; Marcelle A. Siegel; Kristy Halverson; Sharyn Freyermuth

2010-01-01

472

Melanocyte Stem Cells: As an Excellent Model to Study Stem Cell Biology  

Microsoft Academic Search

Elucidation of molecular mechanisms underlying stem cell regulation is of great importance for their clinical applications\\u000a in regenerative medicine and cancer therapy. The function of stem cells is maintained by their specialized microenvironment,\\u000a referred as the niche. Despite intensive studies of the stem cell niche, the molecular basis of stem cell regulation by the\\u000a niche has still remained elusive. Since

Masatake Osawa; Kiyotaka Hasegawa; Mariko Moriyama; Shin-Ichi Nishikawa

473

Stem Cell Clinics Online: The Direct-to-Consumer Portrayal of Stem Cell Medicine  

Microsoft Academic Search

Despite the immature state of stem cell medicine, patients are seeking and ac- cessing putative stem cell therapies in an ''early market'' in which direct-to-con- sumer advertising via the internet likely plays an important role. We analyzed stem cell clinic websites and appraised the relevant published clinical evidence of stem cell therapies to address three questions about the direct-to-consumer portrayal

Darren Lau; Ubaka Ogbogu; Benjamin Taylor; Tania Stafinski; Devidas Menon; Timothy Caulfield

474

[Haematopoietic stem cell transplantation and oral complications].  

PubMed

New haematopoietic stem cell transplantation procedures make the treatment available to patients who previously did not qualify, such as the elderly. In addition, the spectrum of oral complications associated with haematopoietic stem cell transplantation has altered as a result of the recent developments. This article is a review of the main principles of haematopoietic stem cell transplantation and provides information on oral complications which may develop, such as mucositis, infections, bleeding, graft-versus-host disease, xerostomia, hyposalivation, altered taste, secondary tumors, osteoporosis, osteonecrosis and growing and developing disturbancies. Finally, the role of dental care providers in cases of haematopoietic stem cell transplantation is addressed. PMID:19585886

Raber-Durlacher, J E; von dem Borne, P A; Stokman, M A; Gortzak, R A Th

2009-06-01

475

Stem cells in the nervous system.  

PubMed

Given their capacity to regenerate cells lost through injury or disease, stem cells offer new vistas into possible treatments for degenerative diseases and their underlying causes. As such, stem cell biology is emerging as a driving force behind many studies in regenerative medicine. This review focuses on the current understanding of the applications of stem cells in treating ailments of the human brain, with an emphasis on neurodegenerative diseases. Two types of neural stem cells are discussed: endogenous neural stem cells residing within the adult brain and pluripotent stem cells capable of forming neural cells in culture. Endogenous neural stem cells give rise to neurons throughout life, but they are restricted to specialized regions in the brain. Elucidating the molecular mechanisms regulating these cells is key in determining their therapeutic potential as well as finding mechanisms to activate dormant stem cells outside these specialized microdomains. In parallel, patient-derived stem cells can be used to generate neural cells in culture, providing new tools for disease modeling, drug testing, and cell-based therapies. Turning these technologies into viable treatments will require the integration of basic science with clinical skills in rehabilitation. PMID:24800720

Maldonado-Soto, Angel R; Oakley, Derek H; Wichterle, Hynek; Stein, Joel; Doetsch, Fiona K; Henderson, Christopher E

2014-11-01

476

Checkpoints of Melanocyte Stem Cell Development  

NSDL National Science Digital Library

The bulge region of the adult hair follicle contains the niches for both epithelial and melanocyte stem cells. Recent evidence suggests that the development of melanocyte stem cells is controlled by a complex network of transcription factors, including Pax3, Sox10, and Mitf, and of regulatory extracellular cues such as Wnt. However, additional players are likely to be involved. It will be intriguing to identify these signals and to elucidate whether and how neighboring epithelial stem cells influence the balance between melanocyte stem cell maintenance and differentiation.

Lukas Sommer (Swiss Federal Institute of Technology.;Institute of Cell Biology REV)

2005-08-23

477

Generalized Potential of Adult Neural Stem Cells  

NASA Astrophysics Data System (ADS)

The differentiation potential of stem cells in tissues of the adult has been thought to be limited to cell lineages present in the organ from which they were derived, but there is evidence that some stem cells may have a broader differentiation repertoire. We show here that neural stem cells from the adult mouse brain can contribute to the formation of chimeric chick and mouse embryos and give rise to cells of all germ layers. This demonstrates that an adult neural stem cell has a very broad developmental capacity and may potentially be used to generate a variety of cell types for transplantation in different diseases.

Clarke, Diana L.; Johansson, Clas B.; Wilbertz, Johannes; Veress, Biborka; Nilsson, Erik; Karlström, Helena; Lendahl, Urban; Frisén, Jonas

2000-06-01

478

Establishment of a Mesenchymal Stem Cell Bank  

PubMed Central

Adult stem cells have generated great amount of interest amongst the scientific community for their potential therapeutic applications for unmet medical needs. We have demonstrated the plasticity of mesenchymal stem cells isolated from the umbilical cord matrix. Their immunological profile makes it even more interesting. We have demonstrated that the umbilical cord is an inexhaustible source of mesenchymal stem cells. Being a very rich source, instead of discarding this tissue, we worked on banking these cells for regenerative medicine application for future use. The present paper gives a detailed account of our experience in the establishment of a mesenchymal stem cell bank at our facility. PMID:21826152

Cooper, Khushnuma; Viswanathan, Chandra

2011-01-01

479

PEDF & Stem Cells: Niche vs. Nurture.  

PubMed

Anti-angiogenic pigment epithelium-derived factor (PEDF) is a multifunctional 50kD secreted glycoprotein emerging as a key factor in stem cell renewal. Characteristics of the stem cell niche can be highly dependent on location, access to the vasculature, oxygen tension and neighboring cells. In the neural stem cell (NSC) niche, specifically the subventricular zone, PEDF actively participates in the self renewal process and promotes stemness by upregulating Notch signaling effectors Hes1 and Hes5. The local vascular endothelial cells and ependymal cells are the likely sources of PEDF for the NSC while mesenchymal and retinal stem cells can actually produce PEDF. The opposing actions of PEDF and VEGF on various cells are recapitulated in the NSC niche. Intraventricular injection of PEDF promotes stem cell renewal, while injection of VEGF prompts differentiation and neurogenesis in the subventricular zone. Enhancing the expression of PEDF in stem cells has promising therapeutic implications. Bone marrow mesenchymal stem cells overexpressing PEDF effectively inhibited pathologic angiogenesis in the murine eye and these same cells suppressed hepatocellular carcinoma growth. As a protein with bioactivities in nearly all normal organ systems, it is likely that PEDF will continue to gain visibility as an essential component in the development and delivery of novel