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91.
Gechev T Willekens H Van Montagu M Inzé D Van Camp W Toneva V Minkov I 《Journal of plant physiology》2003,160(5):509-515
The effect of elevated light treatment (25 degrees C, PPFD 360 mumol m-2 sec-1) or chilling temperatures combined with elevated light (5 degrees C, PPFD 360 mumol m-2 sec-1) on the activity of six antioxidant enzymes, guaiacol peroxidases, and glutathione peroxidase (GPx, EC 1.11.1.9) protein accumulation were studied in tobacco Nicotiana tabacum cv. Petit Havana SR1. Both treatments caused no photooxidative damage, but chilling caused a transient wilting. The light treatment increased the activities of ascorbate peroxidase (APx, EC 1.11.1.11) and guaiacol peroxidases while catalase (EC 1.11.1.6), superoxide dismutase (SOD, EC 1.15.1.1), monodehydroascorbate reductase (MDHAR, EC 1.6.5.4), dehydroascorbate reductase (DHAR, EC 1.8.5.1), and glutathione reductase (EC 1.6.4.2) were unchanged. In contrast, chilling treatment did not increase any of the antioxidant enzyme activities, but decreased catalase and to a lesser extent DHAR activities. Glutathione peroxidase protein levels increased sporadically under light treatment and constantly under chilling. Both chilling and light stress caused induction of glutathione synthesis and accumulation of oxidised glutathione, although the predominant part of the glutathione pool remained in the reduced form. Antioxidant enzymes from the chilling treated plants were measured at both 25 degrees C and 5 degrees C. Measurements at 5 degrees C revealed a 3-fold reduction in catalase activity, compared with that measured at 25 degrees C, indicating that the overall reduction in catalase after four days of chilling was approximately 10-fold. The overall reduction in activity for the other antioxidant enzymes after four days of chilling was 2-fold for GR and APx, 1.5-fold for MDHAR, 3.5-fold for DHAR. The activity of SOD was the same at 25 and 5 degrees C. These results indicate that catalase and DHAR are most strongly affected by the chilling treatment and may be the rate-limiting factor of the antioxidant system at low temperatures. 相似文献
92.
De Vos A Sermon K Van de Velde H Joris H Vandervorst M Lissens W De Paepe A Liebaers I Van Steirteghem A 《Human genetics》2000,106(6):605-613
Osteogenesis imperfecta (OI) is an autosomal dominant genetic disorder characterized by the presence of brittle bones and decreased bone mass (osteopenia), as a result of mutations in the genes that encode the chains of type I collagen, the major protein of bone. The clinical features of the disease range from death in the perinatal period to normal life span with minimal increase in fractures. The present report describes two polymerase chain reaction (PCR)-based assays allowing preimplantation genetic diagnosis (PGD) on the one hand for OI type I, the mildest form, and on the other hand for OI type IV, which is intermediate in severity between OI type I and OI type III. In the couple referred for PGD for OI type I, the female partner carried a 1-bp deletion in exon 43 of the COL1A1 gene, resulting in a premature stop codon in exon 46. The synthesis of too little type I procollagen results from such a non-functional or COL1A1 null allele. In the other couple, referred for PGD for OI type IV, the male partner carried a G to A substitution in exon 19 of the COL1A2 gene, which results in an abnormal gene product due to an alphaGly247 (GGT) to Ser (AGT) substitution (G247S). Both mutations result in the loss of a specific restriction enzyme recognition site and can therefore be detected by PCR amplification followed by restriction fragment analysis. PCR amplification of genomic DNA of the parents-to-be with one of the two primers fluorescently labelled, followed by automated laser fluorescence (ALF) gel electrophoresis of the amplified and restricted fragments, allowed a distinction between the healthy and affected genotypes. PCR on single Epstein-Barr-virus (EBV)-transformed lymphoblasts resulted in acceptable amplification efficiencies (87% and 85% for OI type I and OI type IV respectively) and the allele drop-out (ADO) rate was assessed at 11.5% and 11.1% for OI type I and OI type IV respectively. With research blastomeres, 100% amplification rates were obtained and no contamination was observed in the blank controls, which validated the tests for clinical application. Embryos obtained after intracytoplasmic sperm injection (ICSI) were evaluated for the presence of the normal genotype of the non-affected parent. For OI type I, two frozen-thawed ICSI-PGD cycles and two fresh ICSI-PGD cycles were carried out for the same couple. The transfer of two unaffected embryos in the last cycle resulted in a twin pregnancy. A twin pregnancy was also achieved in one clinical ICSI-PGD cycle for OI type IV. 相似文献
93.
Our analysis of parts of the mitochondrial ribosomal 12S and 16S genes from 39 populations of Southeast Asian ranid frogs confirms that the fanged frogs are a monophyletic clade. This group, properly called Limnonectes, appears to have arisen in the early Tertiary at a time when free faunal exchange was possible among Southeast Asia, Borneo, Sumatra, Java, and, probably, Sulawesi. Four species groups are tentatively identified within the clade. Part of group 1 includes species related to L. kuhlii that occur in Borneo. Another part of group 1 includes species from Malay Peninsula and Thailand that are related to L. pileata. Species group 2, L. leporina, occurs only in Borneo. Species group 3 is restricted to species distributed in Sulawesi and the Philippines. Species group 4 includes L. blythii and relatives. There is a lack of compatibility between phylogenetic hypotheses generated from molecular and morphological data sets. These differences are related, in large part, to whether some species of Limnonectes have secondarily lost fangs or whether lack of fangs represents the primitive condition. 相似文献
94.
Evidence from cytology, enzyme markers and morphometry suggest that a species of Viola (Violaceae) collected in southeastern Norway should be referred to V. suavis , although differing in some phenotypic traits. V. suavis is not previously known from the Nordic countries, but must now be regarded as an established member of the Norwegian flora. It was probably introduced more than a century ago, providing an interesting analogy to the situation of V. alba in Öland (Sweden). Thus, it seems like human activity have played a role for expanding the distribution areas of several of the species within Viola subsection Viola (V. alba, V. hirta, V. odorata and V. suavis ). Electrophoretic evidence showed that the basal chromosome number of the subsection is x=5. V. suavis (2n=40) is allo-octoploid, and closely related tetraploid taxa were easily recognized. However, it is difficult to trace its origin to lower-ploid ancestors, and it seems likely that the complex may have contained extinct taxa with other allelic combinations that better explain the origin of V. suavis . 相似文献
95.
The J Domain of Simian Virus 40 Large T Antigen Is Required To Functionally Inactivate RB Family Proteins 总被引:16,自引:5,他引:11 下载免费PDF全文
Transformation by simian virus 40 large T antigen (TAg) is dependent on the inactivation of cellular tumor suppressors. Transformation minimally requires the following three domains: (i) a C-terminal domain that mediates binding to p53; (ii) the LXCXE domain (residues 103 to 107), necessary for binding to the retinoblastoma tumor suppressor protein, pRB, and the related p107 and p130; and (iii) an N-terminal domain that is homologous to the J domain of DnaJ molecular chaperone proteins. We have previously demonstrated that the N-terminal J domain of TAg affects the RB-related proteins by perturbing the phosphorylation status of p107 and p130 and promoting the degradation of p130 and that this domain is required for transformation of cells that express either p107 or p130. In this work, we demonstrate that the J domain of TAg is required to inactivate the ability of each member of the pRB family to induce a G1 arrest in Saos-2 cells. Furthermore, the J domain is required to override the repression of E2F activity mediated by p130 and pRB and to disrupt p130-E2F DNA binding complexes. These results imply that while the LXCXE domain serves as a binding site for the RB-related proteins, the J domain plays an important role in inactivating their function. 相似文献
96.
97.
Brigitte Michelsen Ragnhild Fiane Andreas P. Diamantopoulos Dag Magnar Soldal Inger Johanne W. Hansen Tuulikki Sokka Arthur Kavanaugh Glenn Haugeberg 《PloS one》2015,10(4)
Objective
The main objective of this study was to compare disease burden in rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (ax-SpA).Methods
In this cross-sectional study, all the RA (1093), PsA (365) and ax-SpA (333) patients who visited the out-patient clinic of the Hospital of Southern Norway Trust during the year 2013 were included; the RA patients all had a RA diagnosis verified by the treating rheumatologist, the PsA patients all fulfilled the ClASsification for Psoriatic ARthritis (CASPAR) criteria and the ax-SpA patients all fulfilled the Assessment of SpondyloArthritis international Society (ASAS) classification criteria for ax-SpA. Patient-reported health status, demographic variables, medications, and composite scores of disease activity were assessed. The main analyses were performed using General Linear Models adjusted for age, sex and multiple comparisons. Correlation analyses were performed using Spearman’s rho.Results
The reported pain, joint pain, patient’s global assessment and fatigue were similar in PsA and ax-SpA, but significantly lower in RA. The 28-joint Disease Activity Score (DAS28) (0.3±0.1, p = 0.003), Clinical Disease Activity Index (CDAI) (1.0±0.4, p = 0.028) and Routine Assessment of Patient Index Data 3 (RAPID3) (0.4±0.1, p = 0.004) were all significantly higher in PsA vs. RA. RAPID3 showed moderate to high correlation with DAS28 (rho = 0.521, p<0.001) and CDAI (rho = 0.768, p<0.001) in RA and PsA, and with Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) (rho = 0.902, p<0.001) and Bath Ankylosing Spondylitis Functional Index (BASFI) (0.865, p<0.001) in ax-SpA and PsA.Conclusion
In conclusion, patient- reported outcome measures were similar in our population of PsA and ax-SpA patients, but significantly lower for the RA patients. Composite disease activity measures were lower in RA than in PsA and ax-SpA, but the magnitude of these differences was small and probably not of clinical significance. Our study indicates that disease burden in RA, PsA and ax-SpA may be more similar than previously demonstrated. 相似文献98.
Malin Gingnell Elin Bannbers Harmen Moes Jonas Engman Sara Sylvén Alkistis Skalkidou Kristiina Kask Johan Wikstr?m Inger Sundstr?m-Poromaa 《PloS one》2015,10(6)
Marked endocrine alterations occur after delivery. Most women cope well with these changes, but the postpartum period is associated with an increased risk of depressive episodes. Previous studies of emotion processing have focused on maternal–infant bonding or postpartum depression (PPD), and longitudinal studies of the neural correlates of emotion processing throughout the postpartum period in healthy women are lacking. In this study, 13 women, without signs of post partum depression, underwent fMRI with an emotional face matching task and completed the MADRS-S, STAI-S, and EPDS within 48 h (early postpartum) and 4–6 weeks after delivery (late postpartum). Also, data from a previous study including 15 naturally cycling controls assessed in the luteal and follicular phase of the menstrual cycle was used. Women had lower reactivity in insula, middle frontal gyrus (MFG), and inferior frontal gyrus (IFG) in the early as compared to the late postpartum assessment. Insular reactivity was positively correlated with anxiety in the early postpartum period and with depressive symptoms late postpartum. Reactivity in insula and IFG were greater in postpartum women than in non-pregnant control subjects. Brain reactivity was not correlated with serum estradiol or progesterone levels. Increased reactivity in the insula, IFG, and MFG may reflect normal postpartum adaptation, but correlation with self-rated symptoms of depression and anxiety in these otherwise healthy postpartum women, may also suggest that these changes place susceptible women at increased risk of PPD. These findings contribute to our understanding of the neurobiological aspects of the postpartum period, which might shed light on the mechanisms underlying affective puerperal disorders, such as PPD. 相似文献
99.
Charlotte?S.?Bjor?Email authorView authors OrcID profile Emily?Wabuyele Olwen?M.?Grace Inger?Nordal Leonard?E.?Newton 《Journal of ethnobiology and ethnomedicine》2015,11(1):82