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991.
Correlation between CAG Repeat Length and Clinical Features in Machado-Joseph Disease 总被引:19,自引:3,他引:16
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Patrícia Maciel Claudia Gaspar Anita L. DeStefano Isabel Silveira Paula Coutinho Joo Radvany David M. Dawson Lewis Sudarsky Joo Guimares Jose E. L. Loureiro Marjan M. Nezarati Lee I. Corwin Iscia Lopes-Cendes Karen Rooke Roger Rosenberg Patrick MacLeod Lindsay A. Farrer Jorge Sequeiros Guy A. Rouleau 《American journal of human genetics》1995,57(1):54-61
Machado-Joseph disease (MJD) is associated with the expansion of a CAG trinucleotide repeat in a novel gene on 14q32.1. We confirmed the presence of this expansion in 156 MJD patients from 33 families of different geographic origins: 15 Portuguese Azorean, 2 Brazilian, and 16 North American of Portuguese Azorean descent. Normal chromosomes contain between 12 and 37 CAG repeats in the MJD gene, whereas MJD gene carriers have alleles within the expanded range of 62–84 CAG units. The distribution of expanded alleles and the gap between normal and expanded allele sizes is either inconsistent with a premutation hypothesis or most (if not all) of the alleles we studied descend from a common ancestor. There is a strong correlation between the expanded repeat size and the age at onset of the disease as well as the clinical presentation. There is mild instability of the CAG tract length with transmission of the expanded alleles; both increase and decrease in size between parents and progeny occur, with larger variations in male than in female transmissions. Together, these effects can partly explain the variability of age at onset and of phenotypic features in MJD; however, other modifying factors must exist. 相似文献
992.
Anita Lyngstadaas Anders L?bner-Olesen Erik Boye 《Molecular & general genetics : MGG》1995,247(5):546-554
The dam-containing operon in Escherichia coli is located at 74 min on the chromosomal map and contains the genes aroK, aroB, a gene called urf74.3, dam and trpS. We have determined the nucleotide sequence between the dam and trpS genes and show that it encodes two proteins with molecular weights of 24 and 27 kDa. Furthermore, we characterize the three genes urf74.3, 24kDa, 27kDa and the proteins they encode. The predicted amino acid sequences of the 24 and 27 kDa proteins are similar to those of the CbbE and CbbZ proteins, respectively, of the Alcaligenes eutrophus cbb operon, which encodes enzymes involved in the Calvin cycle. In separate experiments, we have shown that the 24 kDa protein has d-ribulose-5-phosphate epimerase activity (similar to CbbE), and we call the gene rpe. Similarly, the 27 kDa protein has 2-phosphoglycolate phosphatase activity (similar to CbbZ), and we name the gene gph. The Urf74.3 protein, with a predicted molecular weight of 46 kDa, migrated as a 70 kDa product under denaturing conditions. Overexpression of Urf74.3 induced cell filamentation, indicating that Urf74.3 directly or indirectly interferes with cell division. We present evidence for translational coupling between aroB and urf74.3 and also between rpe and gph. Proteins encoded in the dam superoperon appear to be largely unrelated: Dam, and perhaps Urf74.3, are involved in cell cycle regulation, AroK, AroB, and TrpS function in aromatic amino acid biosynthesis, whereas Rpe and Gph are involved in carbohydrate metabolism. 相似文献
993.
Solventogenic enzymes of Clostridium acetobutylicum: catalytic properties, genetic organization, and transcriptional regulation 总被引:1,自引:0,他引:1
994.
Lipid peroxidation (LPO) of polyunsaturated fatty acids (PUFAs) is suspected to be involved in the generation of chronic diseases. A model reaction for LPO is the air oxidation of PUFAs initiated by Fe2+ and ascorbic acid. In the course of such model reactions glycolaldehyde (GLA) was detected as main aldehydic product. Since it is difficult to explain the generation of GLA by oxidation of PUFAs, it was suspected that GLA might be derived by oxidation of ascorbic acid. This assumption was verified by treatment of ascorbic acid with Fe2+.
Produced aldehydic compounds were trapped by addition of pentafluorobenzylhydroxylamine hydrochloride (PFBHA-HCl), trimethylsilylated and finally identified by gas chromatography/mass spectrometry (GC/MS). Oxidation of ascorbic acid with O2 in presence of iron ions produced not only glycolaldehyde (GLA), but also glyceraldehyde (GA), dihydroxyacetone (DA) and formaldehyde. Glyoxal (GO) and malondialdehyde (MDA) were detected as trace compounds.
The yield of the aldehydic compounds was increased by addition of lipid hydroperoxides (LOOH) or H2O2. The buffer influenced the reaction considerably: Iron ions react with Tris buffer by producing dihydroxyace-tone (DA). Since ascorbic acid is present in biological systems and Fe2+ ions are obviously generated by cell damaging processes, the production of GLA and other aldehydic components might add to the damaging effects of LPO.
Glucose suffers also oxidation to short-chain aldehydic compounds in aqueous solution, but this reaction requires addition of equimolar amounts of Fe2+ together with equimolar amounts of H2O2 or 13-hydroperoxy-9-cis-11-trans-octadecadienoic acid (13-HPODE). Therefore this reaction, also influenced by the buffer system, seems to be not of biological relevance. 相似文献
Produced aldehydic compounds were trapped by addition of pentafluorobenzylhydroxylamine hydrochloride (PFBHA-HCl), trimethylsilylated and finally identified by gas chromatography/mass spectrometry (GC/MS). Oxidation of ascorbic acid with O2 in presence of iron ions produced not only glycolaldehyde (GLA), but also glyceraldehyde (GA), dihydroxyacetone (DA) and formaldehyde. Glyoxal (GO) and malondialdehyde (MDA) were detected as trace compounds.
The yield of the aldehydic compounds was increased by addition of lipid hydroperoxides (LOOH) or H2O2. The buffer influenced the reaction considerably: Iron ions react with Tris buffer by producing dihydroxyace-tone (DA). Since ascorbic acid is present in biological systems and Fe2+ ions are obviously generated by cell damaging processes, the production of GLA and other aldehydic components might add to the damaging effects of LPO.
Glucose suffers also oxidation to short-chain aldehydic compounds in aqueous solution, but this reaction requires addition of equimolar amounts of Fe2+ together with equimolar amounts of H2O2 or 13-hydroperoxy-9-cis-11-trans-octadecadienoic acid (13-HPODE). Therefore this reaction, also influenced by the buffer system, seems to be not of biological relevance. 相似文献
995.
Manjula S. Thomas Anita Daniel Benny Nair G.M. 《Plant Cell, Tissue and Organ Culture》1997,51(2):145-148
Protocols for in vitro plant regeneration via axillary and adventitious shoot regeneration were established in an important
medicinal plant, Aristolochia indica L. (Aristolochiaceae). Basal Murashige and Skoog's (MS) medium supplemented with 0.54
μM α-naphthaleneacetic acid (NAA) and 13.31 μM benzyladenine (BA) induced the maximum number of shoots (45-50) from shoot
tip and nodal segment cultures. Phenolic accumulation in leaf and internodal stem derived callus cultured in MS medium containing
NAA or 2,4-dichlorophenoxyacetic acid and BA or kinetin was controlled by the addition of 1.0 mg l-1 phloroglucinol (PG) to the callus induction medium. Basal medium supplemented with 2.69 μM NAA, 13.31 μM BA and 1.0 mg l-1 PG induced the best results in terms of shoot bud regeneration from leaf derived callus. Direct de novo development of shoots
from leaf segments was achieved using 13.31 μM BA along with 50 mg l-1 activated charcoal. The microshoots were rooted in White's medium supplemented with 2.46 μM indolebutyric acid. More than
85% of rooted plants survived in the soil.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
996.
S. Kannaiyan S. J. Aruna S. Merina Prem Kumari D. O. Hall 《Journal of applied phycology》1997,9(2):167-174
N2-fixing cyanobacteria (Anabaena azollae, symbiont strains) were immobilized in polyurethane foam and ammonia production by
the cyanobacteria was investigated in the laboratory and rice field. The cyanobacterial symbiont, A. azollae - MPK-SK-AM-24
showed the highest growth rate and biomass production amongst the 5 isolates examined while A. azollae-AS-DS showed the highest
nitrogenase activity followed by A. variabilis - SA0 (wild type, non-symbiotic). Treatment of the foam-immobilized cyanobacteria with the systemic fungicide Bavistin stimulated
nitrogenase activity while inhibiting glutamine synthetase (GS) activity. Free-living A. azollae-MPK-SK-AF-38, A. azollae
- MPK-SK-AM-24 and A. azollae-MPK-SK-AM-27 excreted the highest amounts of ammonia into the growth medium; under foam - immobilized
conditions the ammonia production increased further. Treatment of the foam - immobilized cyanobacteria with the fungicides
Bavistin and Vitavax resulted in ammonia production at significantly higher rates. Rice seedlings (var. ADT 36) grown in the
laboratory in conjunction with foam - immobilized A. azollae showed increased growth. A field experiment with paddy rice and
foam - immobilized A. azollae strains indicated that the cyanobacteria excreted significant amounts of ammonia into the flood
water in the rice fields resulting in increased chlorophyll content of the plants and increased the rice grain and straw yields.
A combination of fertilizer nitrogen and inoculation with foam - immobilized cyanobacteria also significantly increased the
rice grain and straw yield. Additionally, both A. azollae and A. variabilis were immobilized in sugarcane waste (bagasse),
added to rice paddy and resulted in increased rice grain yield.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
997.
Chicita F. Culberson William Louis Culberson Sharon Gowan Anita Johnson 《American journal of botany》1987,74(3):403-414
A high-performance liquid chromatographic method originally devised to provide a reproducible measure of retention is used to determine chemical structures of new compounds in lichens. The method relates retention to a standard homologous series so that retention indices of members of other homologous series are linear with carbon number. When two or more homologs are known, retention of new members of the same series can be accurately predicted. Combining this method with other microchemical techniques allows the determination of structures of lichen depsides in small samples of crustose species for which the total material is meager and known only from the herbarium. The conditions are sufficiently mild that chemical decompositions of labile depsides are avoided. Eight new orcinol-type p-depsides with seven- or nine-carbon oxidized sidechains on one or both rings are reported from an endemic Japanese species, Haematomma pachycarpum. The nine-carbon sidechain is the longest ever found in lichen depsides. These new compounds are higher homologs of the known lichen products confluentic, 2‘-O-methylperlatolic, 4-O-methylolivetoric, and 2‘-C-methylmicrophyllinic acids. In addition, an isocoumarin with a nine-carbon sidechain occurs in some specimens. Haematomma pachycarpum has the most complex secondary-product chemistry thus far reported for any lichen species. The significance of the technique used here lies in providing a way to characterize new compounds in rare or endangered species, thereby completing data sets for phylogenetic reconstructions. 相似文献
998.
999.
Anita Laitinen Sofia Oja Lotta Kilpinen Tanja Kaartinen Johanna Möller Saara Laitinen Matti Korhonen Johanna Nystedt 《Cytotechnology》2016,68(4):891-906
Efficient xenofree expansion methods to replace fetal bovine serum (FBS)-based culture methods are strongly encouraged by the regulators and are needed to facilitate the adoption of mesenchymal stromal cell (MSC)-based therapies. In the current study we established a clinically-compliant and reproducible animal serum-free culture protocol for bone marrow-(BM-) MSCs based on an optimized platelet-derived supplement. Our study compared two different platelet-derived supplements, platelet lysate PL1 versus PL2, produced by two different methods and lysed with different amounts of freeze–thaw cycles. Our study also explored the effect of a low oxygen concentration on BM-MSCs. FBS-supplemented BM-MSC culture served as control. Growth kinetics, differentiation and immunomodulatory potential, morphology, karyotype and immunophenotype was analysed. Growth kinetics in long-term culture was also studied. Based on the initial results, we chose to further process develop the PL1-supplemented culture protocol at 20 % oxygen. The results from 11 individual BM-MSC batches expanded in the chosen condition were consistent, yielding 6.60 × 109 ± 4.74 × 109 cells from only 20 ml of bone marrow. The cells suppressed T-cell proliferation, displayed normal karyotype and typical MSC differentiation potential and phenotype. The BM-MSCs were, however, consistently HLA-DR positive when cultured in platelet lysate (7.5–66.1 %). We additionally show that culture media antibiotics and sterile filtration of the platelet lysate can be successfully omitted. We present a robust and reproducible clinically-compliant culture method for BM-MSCs based on platelet lysate, which enables high quantities of HLA-DR positive MSCs at a low passage number (p2) and suitable for clinical use. 相似文献
1000.
Benjamin B. Policicchio Cuiling Xu Egidio Brocca-Cofano Kevin D. Raehtz Tianyu He Dongzhu Ma Hui Li Ranjit Sivanandham George S. Haret-Richter Tammy Dunsmore Anita Trichel John W. Mellors Beatrice H. Hahn George M. Shaw Ruy M. Ribeiro Ivona Pandrea Cristian Apetrei 《PLoS pathogens》2016,12(9)
Viruses that persist despite seemingly effective antiretroviral treatment (ART) and can reinitiate infection if treatment is stopped preclude definitive treatment of HIV-1 infected individuals, requiring lifelong ART. Among strategies proposed for targeting these viral reservoirs, the premise of the “shock and kill” strategy is to induce expression of latent proviruses [for example with histone deacetylase inhibitors (HDACis)] resulting in elimination of the affected cells through viral cytolysis or immune clearance mechanisms. Yet, ex vivo studies reported that HDACis have variable efficacy for reactivating latent proviruses, and hinder immune functions. We developed a nonhuman primate model of post-treatment control of SIV through early and prolonged administration of ART and performed in vivo reactivation experiments in controller RMs, evaluating the ability of the HDACi romidepsin (RMD) to reactivate SIV and the impact of RMD treatment on SIV-specific T cell responses. Ten RMs were IV-infected with a SIVsmmFTq transmitted-founder infectious molecular clone. Four RMs received conventional ART for >9 months, starting from 65 days post-infection. SIVsmmFTq plasma viremia was robustly controlled to <10 SIV RNA copies/mL with ART, without viral blips. At ART cessation, initial rebound viremia to ~106 copies/mL was followed by a decline to < 10 copies/mL, suggesting effective immune control. Three post-treatment controller RMs received three doses of RMD every 35–50 days, followed by in vivo experimental depletion of CD8+ cells using monoclonal antibody M-T807R1. RMD was well-tolerated and resulted in a rapid and massive surge in T cell activation, as well as significant virus rebounds (~104 copies/ml) peaking at 5–12 days post-treatment. CD8+ cell depletion resulted in a more robust viral rebound (107 copies/ml) that was controlled upon CD8+ T cell recovery. Our results show that RMD can reactivate SIV in vivo in the setting of post-ART viral control. Comparison of the patterns of virus rebound after RMD administration and CD8+ cell depletion suggested that RMD impact on T cells is only transient and does not irreversibly alter the ability of SIV-specific T cells to control the reactivated virus. 相似文献