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41.
We herein report the joint occurrence of an autistic disorder (AD) and X-linked hypophosphatemia. X-linked hypophosphatemia (XLH), an X-linked dominant disorder, is the most common of the inherited renal phosphate wasting disorders. Autism is a pervasive developmental disorder that occurs mainly due to genetic causes. In approximately 6-15% of cases, the autistic phenotype is a part of a broader genetic condition called syndromic autism.Therefore, reports of cases with the joint occurrence of a known genetic syndrome and a diagnosis of ASD by a child psychiatrist are relevant. A joint occurrence does not, however, mean that there is always a causal link between the genetic syndrome and the autistic behavioural phenotype. In this case, there are a number of arguments countering a causal link. 相似文献
42.
Is apoptosis in bovine in vitro produced embryos related to early developmental kinetics and in vivo bull fertility? 总被引:1,自引:0,他引:1
Although several studies have indicated a paternal effect on bovine embryo development, no conclusive data exist on the effect of in vivo bull fertility on apoptosis. Therefore, it was the main objective of this study to compare the apoptotic cell ratio (ACR) in embryos originating from bulls with different in vivo fertility. However, since it is has been demonstrated before that bulls with different in vivo fertility differ in timing of first cleavage, it was necessary to investigate first the effect of timing of development on apoptosis in vitro in order to get an unbiased insight in the contribution of in vivo bull fertility on apoptosis in bovine blastocysts. In the first experiment, bovine embryos (n = 939) were allocated to different groups according to cleavage rate at 30, 36 and 48 hpi and blastocysts were selected at 7 and 8 dpi. The blastocyst rate at 7 dpi was significantly lower in embryos which had first cleaved at 48 hpi than in embryos from the 30 and 36 hpi group (P < 0.05). The ACR after TUNEL in day 7 blastocyst was significantly lower in the 30 hpi group in comparison with the 36 and 48 hpi group (P < 0.05) and lower in day 7 blastocysts than in day 8 blastocysts. In the second experiment, sperm of eight bulls with different non return rates was used for in vitro bovine embryo production (n = 3820 oocytes). Cleavage rates (30, 36 and 48 hpi) and blastocyst rate (7 dpi) were determined. Only very low negative correlations could be found between in vivo and in vitro bull fertility and ACR did not differ between groups derived from sires with either low or normal fertility (P > 0.05). Further research in serum free conditions is needed to confirm that the lower ACR in early cleaved embryos could be mediated by the cooperative interaction of embryos of good quality cultured in group. In vivo bull fertility could hardly be correlated with in vitro blastocyst yield and could not be correlated with appearance of apoptosis. 相似文献
43.
Borlotti A Khir AW Rietzschel ER De Buyzere ML Vermeersch S Segers P 《Journal of applied physiology (Bethesda, Md. : 1985)》2012,113(5):727-735
We recently introduced noninvasive methods to assess local pulse wave velocity (PWV) and wave intensity ((n)dI) in arteries based on measurements of flow velocity (U) and diameter (D). Although the methods were validated in an experimental setting, clinical application remains lacking. The aim of this study was therefore to investigate the effect of age and gender on PWV and (n)dI in the carotid and femoral arteries of an existing population. We measured D and U in the carotid and femoral arteries of 1,774 healthy subjects aged 35-55 yr, a subgroup of the Asklepios population. With the use of the lnDU-loop method, we calculated local PWV, which was used to determine arterial distensibility ((n)Ds). We then used the new algorithm to determine maximum forward and backward wave intensities ((n)dI(+max) and (n)dI(-min), respectively) and the reflection index ((n)RI). On average, PWV was higher, and (n)Ds was lower in the femoral than at the carotid arteries. At the carotid artery, PWV increased with age, but (n)Ds, (n)dI(+max), and (n)dI(-min) decreased; (n)RI did not change with age. At the femoral artery, PWV was higher, and (n)Ds was lower in male, but all parameters did not change significantly with age in both women and men. We conclude that the carotid artery is more affected by the aging process than the femoral artery, even in healthy subjects. The new techniques provide mechanical and hemodynamic parameters, requiring only D and U measurements, both of which can be acquired using ultrasound equipment widely available today, hence their advantage for potential use in the clinical setting. 相似文献
44.
Marie Deghorain Louis-Marie Bobay Pierre R. Smeesters Sabrina Bousbata Marjorie Vermeersch David Perez-Morga Pierre-Alexandre Drèze Eduardo P. C. Rocha Marie Touchon Laurence Van Melderen 《Journal of bacteriology》2012,194(21):5829-5839
Despite increasing interest in coagulase-negative staphylococci (CoNS), little information is available about their bacteriophages. We isolated and sequenced three novel temperate Siphoviridae phages (StB12, StB27, and StB20) from the CoNS Staphylococcus hominis and S. capitis species. The genome sizes are around 40 kb, and open reading frames (ORFs) are arranged in functional modules encoding lysogeny, DNA metabolism, morphology, and cell lysis. Bioinformatics analysis allowed us to assign a potential function to half of the predicted proteins. Structural elements were further identified by proteomic analysis of phage particles, and DNA-packaging mechanisms were determined. Interestingly, the three phages show identical integration sites within their host genomes. In addition to this experimental characterization, we propose a novel classification based on the analysis of 85 phage and prophage genomes, including 15 originating from CoNS. Our analysis established 9 distinct clusters and revealed close relationships between S. aureus and CoNS phages. Genes involved in DNA metabolism and lysis and potentially in phage-host interaction appear to be widespread, while structural genes tend to be cluster specific. Our findings support the notion of a possible reciprocal exchange of genes between phages originating from S. aureus and CoNS, which may be of crucial importance for pathogenesis in staphylococci. 相似文献
45.
Vendeville S Lin TI Hu L Tahri A McGowan D Cummings MD Amssoms K Canard M Last S Van den Steen I Devogelaere B Rouan MC Vijgen L Berke JM Dehertogh P Fransen E Cleiren E van der Helm L Fanning G Van Emelen K Nyanguile O Simmen K Raboisson P 《Bioorganic & medicinal chemistry letters》2012,22(13):4437-4443
Optimization of a novel series of macrocyclic indole-based inhibitors of the HCV NS5b polymerase targeting the finger loop domain led to the discovery of lead compounds exhibiting improved potency in cellular assays and superior pharmacokinetic profile. Further lead optimization performed on the most promising unsaturated-bridged subseries provided the clinical candidate 27-cyclohexyl-12,13,16,17-tetrahydro-22-methoxy-11,17-dimethyl-10,10-dioxide-2,19-methano-3,7:4,1-dimetheno-1H,11H-14,10,2,9,11,17-benzoxathiatetraazacyclo docosine-8,18(9H,15H)-dione, TMC647055 (compound 18a). This non-zwitterionic 17-membered ring macrocycle combines nanomolar cellular potency (EC(50) of 82 nM) with minimal associated cell toxicity (CC(50)>20 μM) and promising pharmacokinetic profiles in rats and dogs. TMC647055 is currently being evaluated in the clinic. 相似文献
46.
Guido Lopes dos Santos Santiago Inge Tency Hans Verstraelen Rita Verhelst Marijke Trog Marleen Temmerman Leen Vancoillie Ellen Decat Piet Cools Mario Vaneechoutte 《PloS one》2012,7(9)
Background
To obtain more detailed understanding of the causes of disturbance of the vaginal microflora (VMF), a longitudinal study was carried out for 17 women during two menstrual cycles.Methods
Vaginal swabs were obtained daily from 17 non-pregnant, menarchal volunteers. For each woman, Gram stains were scored, the quantitative changes of 5 key vaginal species, i.e. Atopobium vaginae, Lactobacillus crispatus, L. iners, (sialidase positive) Gardnerella vaginalis and Prevotella bivia were quantified with qPCR and hydrogen-peroxide production was assessed on TMB+ agar.Results
Women could be divided in 9 subjects with predominantly normal VMF (grades Ia, Ib and Iab, group N) and 8 with predominantly disturbed VMF (grades I-like, II, III and IV, group D).VMF was variable between women, but overall stable for most of the women. Menses were the strongest disturbing factor of the VMF. L. crispatus was present at log7–9 cells/ml in grade Ia, Iab and II VMF, but concentrations declined 100-fold during menses. L. crispatus below log7 cells/ml corresponded with poor H2O2-production. L. iners was present at log 10 cells/ml in grade Ib, II and III VMF. Sialidase negative G. vaginalis strains (average log5 cells/ml) were detected in grade I, I-like and IV VMF. In grade II VMF, predominantly a mixture of both sialidase negative and positive G. vaginalis strains (average log9 cells/ml) were present, and predominantly sialidase positive strains in grade III VMF. The presence of A. vaginae (average log9 cells/ml) coincided with grade II and III VMF. P. bivia (log4–8 cells/ml) was mostly present in grade III vaginal microflora. L. iners, G. vaginalis, A. vaginae and P. bivia all increased around menses for group N women, and as such L. iners was considered a member of disturbed VMF.Conclusions
This qPCR-based study confirms largely the results of previous culture-based, microscopy-based and pyrosequencing-based studies. 相似文献47.
48.
Leen Verbert Bora Lee Sarah L Kocks Zerihun Assefa Jan B Parys Ludwig Missiaen Geert Callewaert Rafael A Fissore Humbert De Smedt Geert Bultynck 《Biology of the cell / under the auspices of the European Cell Biology Organization》2008,100(1):39-49
BACKGROUND INFORMATION: The IP(3)R (inositol 1,4,5-trisphosphate receptor) is a tetrameric channel that accounts for a large part of the intracellular Ca(2+) release in virtually all cell types. We have previously demonstrated that caspase-3-mediated cleavage of IP(3)R1 during cell death generates a C-terminal fragment of 95 kDa comprising the complete channel domain. Expression of this truncated IP(3)R increases the cellular sensitivity to apoptotic stimuli, and it was postulated to be a constitutively active channel. RESULTS: In the present study, we demonstrate that expression of the caspase-3-cleaved C-terminus of IP(3)R1 increased the rate of thapsigargin-mediated Ca(2+) leak and decreased the rate of Ca(2+) uptake into the ER (endoplasmic reticulum), although it was not sufficient by itself to deplete intracellular Ca(2+) stores. We detected the truncated IP(3)R1 in different cell types after a challenge with apoptotic stimuli, as well as in aged mouse oocytes. Injection of mRNA corresponding to the truncated IP(3)R1 blocked sperm factor-induced Ca(2+) oscillations and induced an apoptotic phenotype. CONCLUSIONS: In the present study, we show that caspase-3-mediated truncation of IP(3)R1 enhanced the Ca(2+) leak from the ER. We suggest a model in which, in normal conditions, the increased Ca(2+) leak is largely compensated by enhanced Ca(2+)-uptake activity, whereas in situations where the cellular metabolism is compromised, as occurring in aging oocytes, the Ca(2+) leak acts as a feed-forward mechanism to divert the cell into apoptosis. 相似文献
49.
Fransen M Amery L Hartig A Brees C Rabijns A Mannaerts GP Van Veldhoven PP 《Biochimica et biophysica acta》2008,1783(5):864-873
Tetratricopeptide (TPR)-domain proteins are involved in various cellular processes. The TPR domain is known to be responsible for interaction with other proteins commonly recognizing sequence motifs at the C-termini. One such TPR-protein, TRIP8b, was originally identified in rat as an interaction partner of Rab8b, and its human orthologue as a protein related to the peroxisomal targeting signal 1 (PTS1) receptor Pex5p (Pex5Rp). Somewhat later, the mouse orthologue was reported to bind the hyperpolarization-activated, cyclic nucleotide-regulated HCN channels, and, very recently, the rat orthologue was shown to interact with latrophilin 1, the calcium-independent receptor of alpha-latrotoxin. Here we employed various methodological approaches to investigate and compare the binding specificities of the human PTS1 receptor Pex5p and the related protein Pex5Rp/TRIP8b towards a subset of targets, including Rab8b and various C-termini resembling PTS1. The results show that the TPR domains of Pex5p and Pex5Rp/TRIP8b have distinct but overlapping substrate specificities. This suggests that selectivity in the recognition of substrates by the TPR domains of Pex5p and Pex5Rp/TRIP8b is a matter of considerable complexity, and that no single determinant appears to be sufficient in unambiguously defining a binding target for either protein. This idea is further corroborated by our observations that changes in the surrounding residues or the conformational state of one of the binding partners can profoundly alter their binding activities. The implications of these findings for the possible peroxisome-related functions of Pex5Rp/TRIP8b are discussed. 相似文献
50.