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1.
Water Sci Technol ; 73(5): 1018-24, 2016.
Article de Anglais | MEDLINE | ID: mdl-26942522

RÉSUMÉ

This study evaluated the nitrogen compound removal efficiency of a hybrid subsurface constructed wetland, which began treating milking parlor wastewater in Hokkaido, northern Japan, in 2006. The wetland's overall removal rates of total nitrogen (TN) and ammonium (NH4(+)-N) improved after the second year of operation, and its rate of organic nitrogen (Org-N) removal was stable at 90% efficiency. Only nitrate (NO3(-)-N) levels were increased following the treatment. Despite increased NO3(-)-N (maximum of 3 mg-N/L) levels, TN removal rates were only slightly affected. Removal rates of TN and Org-N were highest in the first vertical bed. NH4(+)-N removal rates were highest in the second vertical bed, presumably due to water recirculation and pH adjustment. Concentrations of NO3(-)-N appeared when total carbon (TC) levels were low, which suggests that low TC prevented complete denitrification in the second vertical bed and the final horizontal bed. In practice, the beds removed more nitrogen than the amount theoretically removed by denitrification, as calculated by the amount of carbon removed from the system. This carbon-nitrogen imbalance may be due to other nitrogen transformation mechanisms, which require less carbon.


Sujet(s)
Azote/composition chimique , Élimination des déchets liquides/méthodes , Eaux usées/composition chimique , Zones humides , Composés d'ammonium , Animaux , Carbone , Bovins , Industrie laitière , Japon , Lait , Nitrates , Facteurs temps
2.
Water Sci Technol ; 73(1): 13-20, 2016.
Article de Anglais | MEDLINE | ID: mdl-26744930

RÉSUMÉ

The objective of this study was to evaluate performance of a hybrid constructed wetland (CW) built for high organic content piggery wastewater treatment in a cold region. The system consists of four vertical and one horizontal flow subsurface CWs. The wetland was built in 2009 and water quality was monitored from the outset. Average purification efficiency of this system was 95±5, 91±7, 89±8, 70±10, 84±15, 90±6, 99±2, and 93±16% for biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total carbon (TC), total nitrogen (TN), ammonium-N (NH4-N), total phosphorus (TP), total coliform (T. Coliform), and suspended solids (SS), respectively during August 2010-December 2013. Pollutant removal rate was 15±18 g m(-2) d(-1), 49±52 g m(-2) d(-1), 6±4 g m(-2) d(-1), 7±5 g m(-2) d(-1), and 1±1 g m(-2) d(-1) for BOD5, COD, TN, NH4-N, and TP, respectively. The removal efficiency of BOD5, COD, NH4-N, and SS improved yearly since the start of operation. With respect to removal of TN and TP, efficiency improved in the first three years but slightly declined in the fourth year. The system performed well during both warm and cold periods, but was more efficient in the warm period. The nitrate increase may be attributed to a low C/N ratio, due to limited availability of carbon required for denitrification.


Sujet(s)
Purification de l'eau/méthodes , Zones humides , Animaux , Carbone/analyse , Basse température , Hébergement animal , Azote/analyse , Phosphore/analyse , Suidae , Eaux usées/analyse , Qualité de l'eau
3.
Water Sci Technol ; 68(7): 1468-76, 2013.
Article de Anglais | MEDLINE | ID: mdl-24135094

RÉSUMÉ

The performance of six multistage hybrid constructed wetland systems was evaluated. The systems were designed to treat four kinds of high-content wastewater: dairy wastewater (three systems, average inflow content 2,400-5,000 mg·COD l(-1), 3-6 years of operation); pig farm wastewater, including liquid food washing wastewater (one system, 9,500 mg·COD l(-1), 3 years); potato starch processing wastewater (one system, 20,000-60,000 mg·COD l(-1), 3 years); and wastewater containing pig farm swine urine (one system, 6,600 mg·COD l(-1), 2.8 years) (COD = chemical oxygen demand). The systems contained three or four vertical (V) flow beds with self-priming siphons and surface partitions and no or one horizontal (H) flow bed (three to five beds). In some V flow beds, treated effluents were recirculated (Vr) through the inlet to improve performance. Mean annual temperature was 5-8 °C at all locations. To overcome clogging due to the high load in a cold climate, we applied a safety bypass structure and floating cover material to the V flow beds. Calculated average oxygen transfer rates (OTRs) increased proportionally with the influent load, and the OTR value was Vr > V> H. The relations of load-OTR, COD-ammonium, and a Arrhenius temperature-dependent equation enable the basic design of a reed bed system.


Sujet(s)
Climat froid , Élimination des déchets liquides/méthodes , Zones humides , Composés d'ammonium , Animaux , Bovins , Manipulation des aliments , Déchets industriels , Japon , Azote , Suidae
4.
J Eur Acad Dermatol Venereol ; 26(6): 710-3, 2012 Jun.
Article de Anglais | MEDLINE | ID: mdl-21707767

RÉSUMÉ

BACKGROUND: Paraneoplastic cutaneous disorders (PCDs) or dermadromes are skin conditions that have an association with internal malignancies but are not themselves malignant. We report the first two cases of systemic anaplastic large cell lymphoma (s-ALCL) accompanied by erythroderma and multiple leg ulcers as PCDs. CASE 1: A 52-year-old Japanese man presented with disseminated itchy papular erythemas which he had over his entire body for the preceding 5 years that later exacerbated to erythroderma. Multiple punched-out ulcers also developed on his lower legs. Superficial lymph nodes (LNs) were swollen, and a left axillary LN biopsy demonstrated dense CD30(+) atypical large cell (ALC) infiltration. By contrast, lymphocytes infiltrating into the erythroderma and leg ulcers were CD30(-) , and T-cell receptor ß (TCRß) chain gene rearrangement was negative in skin biopsy specimens. Thus, he was diagnosed with s-ALCL. Not only his s-ALCL but also his erythroderma and leg ulcers responded well to chemotherapy. CASE 2: A 71-year-old Japanese woman presented with erythroderma that persisted for approximately 20 years after mastectomy. At her initial hospital visit, she was diagnosed with s-ALCL by biopsy of swollen left inguinal LNs. Similar to Case 1, CD30(+) ALCs were negative in skin samples with normal TCRß chain gene rearrangement. As the erythrodermic skin lesion responded well to chemotherapy for s-ALCL, it was considered a PCD. CONCLUSION: s-ALCL development may be predicted by the precedence and concurrence of intractable paraneoplastic erythrodermic and ulcerative skin lesions, as reported in our two cases.


Sujet(s)
Dermatite exfoliatrice/complications , Lymphome à grandes cellules anaplasiques/complications , Syndromes paranéoplasiques/complications , Tumeurs cutanées/complications , Sujet âgé , Dermatite exfoliatrice/immunologie , Dermatite exfoliatrice/physiopathologie , Femelle , Humains , Lymphome à grandes cellules anaplasiques/immunologie , Lymphome à grandes cellules anaplasiques/physiopathologie , Mâle , Adulte d'âge moyen , Syndromes paranéoplasiques/immunologie , Syndromes paranéoplasiques/physiopathologie , Tumeurs cutanées/immunologie , Tumeurs cutanées/physiopathologie
5.
Environ Technol ; 24(7): 889-96, 2003 Jul.
Article de Anglais | MEDLINE | ID: mdl-12916840

RÉSUMÉ

The pollution of lake sediments by organic micro-pollutants has been of growing environmental concern due to their suspected long-term effects on both human health and the surrounding ecosystem. In this research, in order to investigate and evaluate the micro-organic pollution in lake sediments, an analytical methodology consisting of freeze-drying, Soxhlet extraction with dichloromethane, concentration by rotary-evaporator, purification and fractionation by Sep-pak florigil cartridge, and quantification by GC/MS was formulated and applied to the lake sediments of Akanoi Bay, Lake Biwa in Japan. Two polycyclic aromatic hydrocarbons (PAHs) (i.e., fluoranthene and pyrene) were detected in the collected sediment samples. Based on the horizontal distribution of these two PAHs and the particle size distribution of the sediment samples, it was considered that the river inflows (the land usage in their upstream is mainly paddy field andresidential) into the bay are the major pollution sources.


Sujet(s)
Sédiments géologiques/composition chimique , Hydrocarbures aromatiques polycycliques/analyse , Écosystème , Surveillance de l'environnement , Japon , Taille de particule , Mouvements de l'eau
6.
Phys Rev Lett ; 87(21): 217601, 2001 Nov 19.
Article de Anglais | MEDLINE | ID: mdl-11736378

RÉSUMÉ

Accurate charge-density distributions of cubic and tetragonal PbTiO3 and BaTiO3 have been obtained by the MEM(maximum entropy method)/Rietveld analysis using synchrotron-radiation powder data. The Pb-O bonds in tetragonal PbTiO3 show rather strong covalency, while those in cubic PbTiO3 are ionic. This is the clear evidence of the Pb-O hybridization in tetragonal PbTiO3, which has been theoretically predicted as a key factor of much larger ferroelectricity of this substance than that of BaTiO3. Tetragonal PbTiO3 forms a layered structure of a two-dimensional covalent-bonding network consisting of the Ti-O5 pyramid.

7.
Plant Cell ; 13(11): 2409-25, 2001 Nov.
Article de Anglais | MEDLINE | ID: mdl-11701878

RÉSUMÉ

We investigated gene activity within the giant embryos of the scarlet runner bean (Phaseolus coccineus) to gain understanding of the processes by which the apical and basal cells become specified to follow different developmental pathways after division of the zygote. We identified two mRNAs, designated G564 and C541, that accumulate specifically within the suspensor of globular-stage embryos. G564 mRNA accumulates uniformly throughout the suspensor, whereas C541 mRNA accumulates to a higher level within the large basal cells of the suspensor that anchor the embryo to the surrounding seed tissue. Both G564 and C541 mRNAs begin to accumulate shortly after fertilization and are present within the two basal cells of embryos at the four-cell stage. In contrast, at the same stage, these mRNAs are not detectable within the two descendants of the apical cell. Nor are they detectable within cells of the embryo sac before fertilization, including the egg cell. We used a G564/beta-glucuronidase reporter gene to show that the G564 promoter is activated specifically within the basal region and suspensor of preglobular tobacco embryos. Analysis of the G564 promoter identified a sequence domain required for transcription within the suspensor that contains several copies of a conserved motif. These results show that derivatives of the apical and basal cells transcribe different genes as early as the four-cell stage of embryo development and suggest that the apical and basal cells are specified at the molecular level after division of the zygote.


Sujet(s)
Régulation de l'expression des gènes végétaux , Phaseolus/croissance et développement , ARN messager/génétique , ARN des plantes/génétique , Graines/physiologie , Séquence nucléotidique , Banque de gènes , Gènes rapporteurs , Hybridation in situ , Données de séquences moléculaires , Végétaux génétiquement modifiés , Régions promotrices (génétique) , ARN des plantes/isolement et purification , RT-PCR , Alignement de séquences , Similitude de séquences d'acides nucléiques , Nicotiana/génétique , Transcription génétique , Transformation génétique
8.
Proc Natl Acad Sci U S A ; 98(24): 14156-61, 2001 Nov 20.
Article de Anglais | MEDLINE | ID: mdl-11698668

RÉSUMÉ

All plants flower late in their life cycle. For example, in Arabidopsis, the shoot undergoes a transition and produces reproductive flowers after the adult phase of vegetative growth. Much is known about genetic and environmental processes that control flowering time in mature plants. However, little is understood about the mechanisms that prevent plants from flowering much earlier during embryo and seedling development. Arabidopsis embryonic flower (emf1 and emf2) mutants flower soon after germination, suggesting that a floral repression mechanism is established in wild-type plants that prevents flowering until maturity. Here, we show that polycomb group proteins play a central role in repressing flowering early in the plant life cycle. We found that mutations in the Fertilization Independent Endosperm (FIE) polycomb gene caused the seedling shoot to produce flower-like structures and organs. Flower-like structures were also generated from the hypocotyl and root, organs not associated with reproduction. Expression of floral induction and homeotic genes was derepressed in mutant embryos and seedlings. These results suggest that FIE-mediated polycomb complexes are an essential component of a floral repression mechanism established early during plant development.


Sujet(s)
Protéines d'Arabidopsis , Arabidopsis/croissance et développement , Protéines végétales/physiologie , Protéines de répression/physiologie , Arabidopsis/embryologie , Arabidopsis/génétique , Fusion artificielle de gènes , Caulimovirus/génétique , Expression des gènes , Gènes de plante , Vecteurs génétiques , Protéines à fluorescence verte , Protéines luminescentes/génétique , Protéines végétales/génétique , Protéines du groupe Polycomb , Régions promotrices (génétique) , Protéines de répression/génétique , Graines , Facteurs temps , Transgènes
9.
J Am Chem Soc ; 123(44): 10884-8, 2001 Nov 07.
Article de Anglais | MEDLINE | ID: mdl-11686690

RÉSUMÉ

Some molecules that have a molecular skeleton similar to stilbenes and azobenzenes are known to show an orientational disorder in the crystals. Some of the disorders are known to be dynamic and mediated by a pedal motion in crystals. Dynamic processes of (E)-stilbene (1) and (E)-3,3',4,4'-tetramethylazobenzene (2) in the crystals were investigated by X-ray diffraction analyses. The dynamic disorder and the pedal motion were detected at higher temperature, even in the molecules that showed no traces of the disorder at room temperature. The results demonstrated that the pedal motion should always be taken into account, even if no disorder is detected. The reasons for the nonoccurrence of the disorder and for the prevalence of the pedal motion are also discussed.

10.
Radiat Med ; 19(5): 263-6, 2001.
Article de Anglais | MEDLINE | ID: mdl-11724257

RÉSUMÉ

OBJECTIVE: Percutaneous laser disk decompression (PLDD) is an effective treatment for bulging or protruding disk. The aim of this study was to present a method of PLDD for cervical disk hernia under CT guidance and to evaluate the efficacy and safety of this procedure. MATERIALS AND METHODS: Seven patients with radiculalgia caused by cervical disk hernia were treated overnight by PLDD. A laser fiber was inserted through an 18 G needle into the target disk under CT guidance. A Nd-Yag laser (1,064 nm) was used for ablation. A CT scan was obtained every 60 joule (J) at the slice of the target disk to visualize the vaporized area during the procedure. The Japan Orthopedic Association (JOA) score of cervical radiculopathy (full score 15) and MacNab criteria were used for assessment of treatment response. RESULTS: Puncture of the needle to the target disk was safely performed under CT guidance. The total dosage of laser ablation ranged from 120 to 500 J (average, 266 J). The overall success rate according to MacNab criteria was good in all cases. No complications were observed in our series. CONCLUSION: The CT-guided technique provides safe, accurate PLDD for cervical disk hernia. PLDD for cervical disk hernia shows promise in the management of radiculalgia.


Sujet(s)
Vertèbres cervicales , Déplacement de disque intervertébral/chirurgie , Thérapie laser , Tomodensitométrie , Femelle , Humains , Déplacement de disque intervertébral/imagerie diagnostique , Mâle , Adulte d'âge moyen
11.
Nat Immunol ; 2(11): 1048-53, 2001 Nov.
Article de Anglais | MEDLINE | ID: mdl-11668343

RÉSUMÉ

A key step in T cell development involves the positive selection of cells that recognize antigen presented by self-major histocompatibility complex. Yet, the signals that are activated by T cell receptor engagement and lead to cell survival remain unclear. We show here that mice lacking the transcription factor Schnurri-2 (Shn-2), a large metal-finger protein, had severely defective positive selection of CD4+ and CD8+ cells. Drosophila Shn acts as a cofactor of Smad homolog and is required for Decapentaplegic signaling. Vertebrates have at least three Shn orthologs (Shn-1, Shn-2 and Shn-3), which are thought to act as nuclear targets in the bone morphogenetic protein-transforming growth factor-beta-activin signaling pathways. These data raised the possibility that the Smad-Shn-2 complex is involved in the thymic selection of T cells.


Sujet(s)
Protéines de transport/physiologie , Délétion clonale/physiologie , Protéines de liaison à l'ADN/physiologie , Autotolérance/physiologie , Sous-populations de lymphocytes T/anatomopathologie , Thymus (glande)/anatomopathologie , Activines/physiologie , Animaux , Cellules de la moelle osseuse/métabolisme , Transplantation de moelle osseuse , Protéines morphogénétiques osseuses/physiologie , Lymphocytes T CD4+/cytologie , Lymphocytes T CD4+/immunologie , Lymphocytes T CD8+/cytologie , Lymphocytes T CD8+/immunologie , Protéines de transport/génétique , Protéines de liaison à l'ADN/déficit , Protéines de liaison à l'ADN/génétique , Protéines de Drosophila/physiologie , Drosophila melanogaster/embryologie , Drosophila melanogaster/génétique , Cellules épithéliales/cytologie , Femelle , Régulation de l'expression des gènes au cours du développement , Ciblage de gène , Mâle , Souris , Souris de lignée BALB C , Souris de lignée C57BL , Souris knockout , Facteur de transcription NF-kappa B/métabolisme , Chimère post-radique , Transduction du signal , Protéine Smad-4 , Spécificité d'espèce , Rate/immunologie , Rate/anatomopathologie , Cellules stromales/métabolisme , Sous-populations de lymphocytes T/immunologie , Thymus (glande)/immunologie , Thymus (glande)/transplantation , Transactivateurs/génétique , Transactivateurs/physiologie , Facteurs de transcription/physiologie , Facteur de croissance transformant bêta/physiologie
12.
Plant Cell Physiol ; 42(10): 1112-8, 2001 Oct.
Article de Anglais | MEDLINE | ID: mdl-11673627

RÉSUMÉ

Biosynthetic pathways for carotenoids in the purple photosynthetic bacterium, Rubrivivax gelatinosus, which synthesizes spirilloxanthin in addition to spheroidene and OH-spheroidene, were investigated by means of genetic manipulation. A phytoene desaturase gene (crtI) found in the photosynthesis gene cluster of this bacterium was expressed in an Escherichia coli strain that can produce phytoene. Both neurosporene and lycopene were synthesized in the recombinant, probably by three- and four-step desaturation reactions of CrtI. A mutant of RVI: gelatinosus lacking the crtI gene produced only phytoene, indicating that this organism had no other phytoene desaturases. When the crtI deletion mutant was complemented by the three-step phytoene desaturase of Rhodobacter capsulatus, spirilloxanthin and its precursors were not synthesized, although spheroidene and OH-spheroidene were accumulated. It was concluded that neurosporene and lycopene are produced by a single phytoene desaturase in RVI: gelatinosus resulting in the synthesis of spheroidene and spirilloxanthin, and that there are no pathways for spirilloxanthin synthesis via spheroidene.


Sujet(s)
Bactéries/enzymologie , Caroténoïdes/biosynthèse , Oxidoreductases/métabolisme , Chromatographie en phase liquide à haute performance , Escherichia coli/génétique , Test de complémentation , Lycopène , Oxidoreductases/génétique
13.
Proc Natl Acad Sci U S A ; 98(20): 11806-11, 2001 Sep 25.
Article de Anglais | MEDLINE | ID: mdl-11573014

RÉSUMÉ

The Arabidopsis LEAFY COTYLEDON2 (LEC2) gene is a central embryonic regulator that serves critical roles both early and late during embryo development. LEC2 is required for the maintenance of suspensor morphology, specification of cotyledon identity, progression through the maturation phase, and suppression of premature germination. We cloned the LEC2 gene on the basis of its chromosomal position and showed that the predicted polypeptide contains a B3 domain, a DNA-binding motif unique to plants that is characteristic of several transcription factors. We showed that LEC2 RNA accumulates primarily during seed development, consistent with our finding that LEC2 shares greatest similarity with the B3 domain transcription factors that act primarily in developing seeds, VIVIPAROUS1/ABA INSENSITIVE3 and FUSCA3. Ectopic, postembryonic expression of LEC2 in transgenic plants induces the formation of somatic embryos and other organ-like structures and often confers embryonic characteristics to seedlings. Together, these results suggest that LEC2 is a transcriptional regulator that establishes a cellular environment sufficient to initiate embryo development.


Sujet(s)
Protéines d'Arabidopsis , Arabidopsis/génétique , Protéines liant les séquences stimulatrices de type CCAAT , Protéines liant les séquences stimulatrices de type CCAAT/génétique , Protéines G , Protéines végétales/génétique , Protéines , Protéines de répression , Protéines de Saccharomyces cerevisiae , Facteurs de transcription/génétique , Séquence d'acides aminés , Arabidopsis/croissance et développement , Protéines liant les séquences stimulatrices de type CCAAT/composition chimique , Complexe du signalosome COP9 , Cotylédon/croissance et développement , Cotylédon/physiologie , Protéines fongiques/génétique , Régulation de l'expression des gènes au cours du développement , Protéines et peptides de signalisation intracellulaire , Mitogen-Activated Protein Kinases/génétique , Données de séquences moléculaires , Feuilles de plante/métabolisme , Protéines végétales/composition chimique , Racines de plante/métabolisme , Graines/physiologie , Alignement de séquences , Facteurs de transcription/composition chimique
14.
Childs Nerv Syst ; 17(8): 500-2, 2001 Aug.
Article de Anglais | MEDLINE | ID: mdl-11508543

RÉSUMÉ

We report a pediatric case of acute cerebellitis with hydrocephalus requiring emergency placement of external ventricular drainage. A 7-year-old boy presented with acute development of headache, nausea and vomiting. Magnetic resonance (MR) examination revealed obstructive hydrocephalus and marked bilateral cerebellar swelling on T2-weighted imaging. After the placement of external ventricular drainage, symptoms of intracranial hypertension promptly improved, and other clinical and radiological abnormalities gradually resolved following intravenous injection of corticosteroids. Surgical treatment and timing in the treatment of acute cerebellitis are discussed.


Sujet(s)
Maladies du cervelet/complications , Maladies du cervelet/chirurgie , Hydrocéphalie/étiologie , Infections de l'appareil respiratoire/complications , Maladie aigüe , Maladies du cervelet/imagerie diagnostique , Maladies du cervelet/anatomopathologie , Ventricules cérébraux/chirurgie , Enfant , Drainage , Humains , Hydrocéphalie/imagerie diagnostique , Hydrocéphalie/anatomopathologie , Hypertension intracrânienne/étiologie , Imagerie par résonance magnétique , Mâle , Syndrome , Tomodensitométrie , Résultat thérapeutique
15.
J Synchrotron Radiat ; 8(Pt 2): 363-5, 2001 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-11512781

RÉSUMÉ

In a conventional in-laboratory XAFS apparatus using conventional X-ray source, sealed tube or rotating anode, has been used. In which the X-ray source is fixed and the sample is moved (translated and rotated). Hence it has been difficult or required a complex method in order to put a heavy element, such as a cryogenic cooler, high temperature furnace and an in-situ reacting cell, at a sample position. Nowadays, there is a strong demand for obtaining dynamic information of a sample and in-situ observation becomes almost unavoidable. We have developed a compact X-ray tube and a new goniometer on which X-ray source is moved and monochromatic X-ray comes out of goniometer is fixed. Therefore it becomes easier to put a various cell at a sample position.

16.
No Shinkei Geka ; 29(5): 421-5, 2001 May.
Article de Japonais | MEDLINE | ID: mdl-11449713

RÉSUMÉ

We reported a case with dural arteriovenous fistula (dAVF) of the anterior cranial fossa associated with occlusion of the left cervical internal carotid artery. A 73-year-old man was admitted with total aphasia and right hemiparesis. Computed tomography showed an ischemic lesion of the left cerebral hemisphere and old infarction of the left occipital lobe. Angiography revealed occlusion of the left cervical internal carotid artery and dAVF of the anterior cranial fossa, fed by the left middle meningeal and the right anterior ethmoidal artery. Follow-up angiography revealed spontaneous recanalization and severe arteriosclerosis of the left internal carotid artery. After marked improvement of neurological deficits, the patient underwent surgical clipping of the draining veins to occlude the dAVF of the anterior cranial fossa. We speculated that marked development of the collateral circulation from the external carotid system might result in the occurrence of dAVF of the anterior cranial fossa.


Sujet(s)
Thrombose carotidienne/complications , Artère carotide interne , Malformations vasculaires du système nerveux central/étiologie , Dure-mère/vascularisation , Sujet âgé , Humains , Mâle
17.
Plant Physiol ; 126(2): 717-30, 2001 Jun.
Article de Anglais | MEDLINE | ID: mdl-11402200

RÉSUMÉ

We identified a T-DNA-generated mutation in the chaperonin-60alpha gene of Arabidopsis that produces a defect in embryo development. The mutation, termed schlepperless (slp), causes retardation of embryo development before the heart stage, even though embryo morphology remains normal. Beyond the heart stage, the slp mutation results in defective embryos with highly reduced cotyledons. slp embryos exhibit a normal apical-basal pattern and radial tissue organization, but they are morphologically retarded. Even though slp embryos are competent to transcribe two late-maturation gene markers, this competence is acquired more slowly as compared with wild-type embryos. slp embryos also exhibit a defect in plastid development-they remain white during maturation in planta and in culture. Hence, the overall developmental phenotype of the slp mutant reflects a lesion in the chloroplast that affects embryo development. The slp phenotype highlights the importance of the chaperonin-60alpha protein for chloroplast development and subsequently for the proper development of the plant embryo and seedling.


Sujet(s)
Arabidopsis/embryologie , Chaperonine-60/génétique , Mutation , Graines/croissance et développement , Séquence d'acides aminés , Arabidopsis/génétique , Chaperonine-60/composition chimique , ADN bactérien , ADN complémentaire , Test de complémentation , Germination , Données de séquences moléculaires , ARN messager/génétique , ARN messager/métabolisme , Similitude de séquences d'acides aminés , Transformation génétique
18.
J Mol Evol ; 52(4): 333-41, 2001 Apr.
Article de Anglais | MEDLINE | ID: mdl-11343129

RÉSUMÉ

A 37-kb photosynthesis gene cluster was sequenced in a photosynthetic bacterium belonging to the beta subclass of purple bacteria (Proteobacteria), Rubrivivax gelatinosus. The cluster contained 12 bacteriochlorophyll biosynthesis genes (bch), 7 carotenoid biosynthesis genes (crt), structural genes for photosynthetic apparatuses (puf and puh), and some other related genes. The gene arrangement was markedly different from those of other purple photosynthetic bacteria, while two superoperonal structures, crtEF-bchCXYZ-puf and bchFNBHLM-lhaA-puhA, were conserved. Molecular phylogenetic analyses of these photosynthesis genes showed that the photosynthesis gene cluster of Rvi. gelatinosus was originated from those of the species belonging to the alpha subclass of purple bacteria. It was concluded that a horizontal transfer of the photosynthesis gene cluster from an ancestral species belonging to the alpha subclass to that of the beta subclass of purple bacteria had occurred and was followed by rearrangements of the operons in this cluster.


Sujet(s)
Bactériochlorophylles/génétique , Photosynthèse/génétique , Proteobacteria/génétique , Séquence d'acides aminés , Bactériochlorophylles/métabolisme , Séquence nucléotidique , Réarrangement des gènes , Gènes bactériens/physiologie , Famille multigénique/physiologie , Opéron/génétique , Photosynthèse/physiologie , Phylogenèse , Similitude de séquences d'acides aminés , Similitude de séquences d'acides nucléiques
19.
Comput Methods Programs Biomed ; 66(1): 17-24, 2001 Jul.
Article de Anglais | MEDLINE | ID: mdl-11378217

RÉSUMÉ

To evaluate the practical usefulness of several types of the reporting system especially for radiologists, we have developed and employed several reporting systems. We categorized those reporting systems as follows (1) stand alone PC reporting system; (2) linked reporting system with PACS environment; (3) integrated three-dimensional (3D) imaging workstation (WS) with the intranet. We have evaluated the advantages and disadvantages of those three systems, and compared between the reporting system without PACS and network reporting system with PACS. Using linked reporting system with PACS, radiologists could easily reference both previous reports and archived diagnostic images, and also make their teaching files quickly. In conclusion, the reporting system under PACS environment is found to be practical and helpful for Japanese radiologists.


Sujet(s)
Micro-ordinateurs , , Systèmes d'information de radiologie , Humains , Imagerie tridimensionnelle , Systèmes d'information de radiologie/instrumentation , Voix
20.
Proc Natl Acad Sci U S A ; 98(10): 5874-9, 2001 May 08.
Article de Anglais | MEDLINE | ID: mdl-11320217

RÉSUMÉ

Fibroblast growth factor-2 (FGF-2) promotes proliferation of neuroprogenitor cells in culture and is up-regulated within brain after injury. Using mice genetically deficient in FGF-2 (FGF-2(-/-) mice), we addressed the importance of endogenously generated FGF-2 on neurogenesis within the hippocampus, a structure involved in spatial, declarative, and contextual memory, after seizures or ischemic injury. BrdUrd incorporation was used to mark dividing neuroprogenitor cells and NeuN expression to monitor their differentiation into neurons. In the wild-type strain, hippocampal FGF-2 increased after either kainic acid injection or middle cerebral artery occlusion, and the numbers of BrdUrd/NeuN-positive cells significantly increased on days 9 and 16 as compared with the controls. In FGF-2(-/-) mice, BrdUrd labeling was attenuated after kainic acid or middle cerebral artery occlusion, as was the number of neural cells colabeled with both BrdUrd and NeuN. After FGF-2(-/-) mice were injected intraventricularly with a herpes simplex virus-1 amplicon vector carrying FGF-2 gene, the number of BrdUrd-labeled cells increased significantly to values equivalent to wild-type littermates after kainate seizures. These results indicate that endogenously synthesized FGF-2 is necessary and sufficient to stimulate proliferation and differentiation of neuroprogenitor cells in the adult hippocampus after brain insult.


Sujet(s)
Lésions encéphaliques/anatomopathologie , Facteur de croissance fibroblastique de type 2/physiologie , Hippocampe/anatomopathologie , Animaux , Lésions encéphaliques/métabolisme , Broxuridine , Hippocampe/métabolisme , Immunohistochimie , Souris , Souris knockout
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