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81.
OBJECTIVE: To investigate neutrophil NADPH oxidase activation and subsequent production of reactive oxygen species (ROS) in pre-eclampsia. DESIGN: Baseline values and the activated response of neutrophils upon stimulation of the NADPH oxidase with the agonists was measured. Neutrophils from 17 third-trimester pre-eclamptic and 17 age- and gestation-matched normal pregnant women were examined. METHODS: Neutrophil ROS production was measured by both lucigenin- and luminol-derived chemiluminescence. The abundance of the various phox proteins was examined using Western blotting techniques. Lucigenin-derived ROS generation was significantly increased in neutrophils isolated from women with pre-eclampsia compared with normotensive controls in the case of both agonists [n-formyl-met-leu-phe (fMLP): pre-eclamptic 2.071 +/- 0.336 relative light units seconds (RLU.s) and normotensive 1.141 +/- 0.249 RLU.s, P = 0.035; phorbol-12-myristate-13-acetate (PMA): pre-eclamptic 34.954 +/- 2.634 RLU.s and normotensive 17.208 +/- 3.325 RLU.s, P = 0.0001]. Luminol-derived ROS generation was also significantly increased in the neutrophils isolated from the women with pre-eclampsia compared with the normotensive controls in the case of both agonists (fMLP: pre-eclamptic 1.955 +/- 0.316 RLU.s and normotensive 1.058 +/- 0.191 RLU.s, P = 0.023; PMA: pre-eclamptic 4.108 +/- 0.351 RLU.s and normotensive 3.073 +/- 0.332 RLU.s, P = 0.042). There were no differences between the relative abundance of the phox proteins in the two groups. CONCLUSIONS: Neutrophils isolated from women with pre-eclampsia during the third trimester showed increased sensitivity to agonist stimulation and produced significantly more ROS than age-matched normotensive controls. This was not due to an increased abundance of any of the phox proteins. Increased ROS production in pre-eclampsia may highlight a role for neutrophils in the oxidative stress and associated endothelial dysfunction that are characteristic of the condition.  相似文献   
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Loss-of-function variants in ANKRD11 were identified as the cause of KBG syndrome, an autosomal dominant syndrome with specific dental, neurobehavioural, craniofacial and skeletal anomalies. We present the largest cohort of KBG syndrome cases confirmed by ANKRD11 variants reported so far, consisting of 20 patients from 13 families. Sixteen patients were molecularly diagnosed by Sanger sequencing of ANKRD11, one familial case and three sporadic patients were diagnosed through whole-exome sequencing and one patient was identified through genomewide array analysis. All patients were evaluated by a clinical geneticist. Detailed orofacial phenotyping, including orthodontic evaluation, intra-oral photographs and orthopantomograms, was performed in 10 patients and revealed besides the hallmark feature of macrodontia of central upper incisors, several additional dental anomalies as oligodontia, talon cusps and macrodontia of other teeth. Three-dimensional (3D) stereophotogrammetry was performed in 14 patients and 3D analysis of patients compared with controls showed consistent facial dysmorphisms comprising a bulbous nasal tip, upturned nose with a broad base and a round or triangular face. Many patients exhibited neurobehavioural problems, such as autism spectrum disorder or hyperactivity. One-third of patients presented with (conductive) hearing loss. Congenital heart defects, velopharyngeal insufficiency and hip anomalies were less frequent. On the basis of our observations, we recommend cardiac assessment in children and regular hearing tests in all individuals with a molecular diagnosis of KBG syndrome. As ANKRD11 is a relatively common gene in which sequence variants have been identified in individuals with neurodevelopmental disorders, it seems an important contributor to the aetiology of both sporadic and familial cases.  相似文献   
84.
KIF1A is a neuron‐specific motor protein that plays important roles in cargo transport along neurites. Recessive mutations in KIF1A were previously described in families with spastic paraparesis or sensory and autonomic neuropathy type‐2. Here, we report 11 heterozygous de novo missense mutations (p.S58L, p.T99M, p.G102D, p.V144F, p.R167C, p.A202P, p.S215R, p.R216P, p.L249Q, p.E253K, and p.R316W) in KIF1A in 14 individuals, including two monozygotic twins. Two mutations (p.T99M and p.E253K) were recurrent, each being found in unrelated cases. All these de novo mutations are located in the motor domain (MD) of KIF1A. Structural modeling revealed that they alter conserved residues that are critical for the structure and function of the MD. Transfection studies suggested that at least five of these mutations affect the transport of the MD along axons. Individuals with de novo mutations in KIF1A display a phenotype characterized by cognitive impairment and variable presence of cerebellar atrophy, spastic paraparesis, optic nerve atrophy, peripheral neuropathy, and epilepsy. Our findings thus indicate that de novo missense mutations in the MD of KIF1A cause a phenotype that overlaps with, while being more severe, than that associated with recessive mutations in the same gene.  相似文献   
85.

Purpose

We recently reported that high thymidine phosphorylase (TP) expression is accompanied by low tumor thymidine concentration and high 3′-deoxy-3′-[18F]fluorothymidine ([18F]FLT) uptake in four untreated lung cancer xenografts. Here, we investigated whether this relationship also holds true for a broader range of tumor models.

Procedures

Lysates from n = 15 different tumor models originating from n = 6 institutions were tested for TP and thymidylate synthase (TS) expression using western blots. Results were correlated to [18F]FLT accumulation in the tumors as determined by positron emission tomography (PET) measurements in the different institutions and to previously published thymidine concentrations.

Results

Expression of TP correlated positively with [18F]FLT SUVmax (ρ = 0.549, P < 0.05). Furthermore, tumors with high TP levels possessed lower levels of thymidine (ρ = ??0.939, P < 0.001).

Conclusions

In a broad range of tumors, [18F]FLT uptake as measured by PET is substantially influenced by TP expression and tumor thymidine concentrations. These data strengthen the role of TP as factor confounding [18F]FLT uptake.
  相似文献   
86.

Purpose

Positron emission tomography (PET) with Zirconium-89 (Zr-89)-labeled antibodies can be used for in vivo quantification of antibody uptake. Knowledge about measurement variability is required to ensure correct interpretation. However, no clinical studies have been reported on measurement variability of Zr-89 immuno-PET. As variability due to low signal-to-noise is part of the total measurement variability, the aim of this study was to assess noise-induced variability of Zr-89 -immuno-PET using count-reduced clinical images.

Procedures

Data were acquired from three previously reported clinical studies with [89Zr]antiCD20 (74 MBq, n?=?7), [89Zr]antiEGFR (37 MBq, n?=?7), and [89Zr]antiCD44 (37 MBq, n?=?13), with imaging obtained 1 to 6 days post injection (D0–D6). Volumes of interest (VOIs) were manually delineated for liver, spleen, kidney, lung, brain, and tumor. For blood pool and bone marrow, fixed-size VOIs were used. Original PET list mode data were split and reconstructed, resulting in two count-reduced images at 50 % of the original injected dose (e.g., 37 MBq74inj).Repeatability coefficients (RC) were obtained from Bland-Altman analysis on standardized uptake values (SUV) derived from VOIs applied to these images.

Results

The RC for the combined manually delineated organs for [89Zr] antiCD20 (37 MBq74inj) increased from D0 to D6 and was less than 6 % at all time points. Blood pool and bone marrow had higher RC, up to 43 % for 37 MBq74inj at D6. For tumor, the RC was up to 42 % for [89Zr]antiCD20 (37 MBq74inj). For [89Zr]antiCD20, (18 MBq74inj), [89Zr]antiEGFR (18 MBq37inj), and [89Zr]antiCD44 (18 MBq37inj), measurement variability was independent of the investigated antibody.

Conclusions

Based on this study, noise-induced variability results in a RC for Zr-89-immuno-PET (37 MBq) around 6 % for manually delineated organs combined, increasing up to 43 % at D6 for blood pool and bone marrow, assuming similar biodistribution of antibodies. The signal-to-noise ratio leads to tumor RC up to 42 %.
  相似文献   
87.
Identification of gene‐environment interaction (G × E) is important in understanding the etiology of complex diseases. Based on our previously developed Set Based gene EnviRonment InterAction test (SBERIA), in this paper we propose a powerful framework for enhanced set‐based G × E testing (eSBERIA). The major challenge of signal aggregation within a set is how to tell signals from noise. eSBERIA tackles this challenge by adaptively aggregating the interaction signals within a set weighted by the strength of the marginal and correlation screening signals. eSBERIA then combines the screening‐informed aggregate test with a variance component test to account for the residual signals. Additionally, we develop a case‐only extension for eSBERIA (coSBERIA) and an existing set‐based method, which boosts the power not only by exploiting the G‐E independence assumption but also by avoiding the need to specify main effects for a large number of variants in the set. Through extensive simulation, we show that coSBERIA and eSBERIA are considerably more powerful than existing methods within the case‐only and the case‐control method categories across a wide range of scenarios. We conduct a genome‐wide G × E search by applying our methods to Illumina HumanExome Beadchip data of 10,446 colorectal cancer cases and 10,191 controls and identify two novel interactions between nonsteroidal anti‐inflammatory drugs (NSAIDs) and MINK1 and PTCHD3.  相似文献   
88.
89.
Background: This paper reviews research on the relation of attachment and substance use disorders (SUD) in adolescence. Based on a theoretical introduction, we review evidence for a possible general link between SUD and insecure attachment, for links between specific forms of SUD and specific patterns of attachment, and for studies on family patterns of attachment in adolescence. Methods: Using medical and psychological databases, we identified 10 studies on adolescent SUD and another 13 studies on adult SUD. Results: Empirical evidence strongly supports the assumption of insecure attachment in SUD samples. With regard to specific patterns of attachment, results mainly point towards fearful and dismissing-avoidance, whereas single studies report preoccupied and unresolved patterns. Results indicate different patterns of attachment in different groups of substance abusers, that is, fearful-avoidant attachment in heroin addicts and more heterogeneous results in abusers of other substances. Explorative data suggest different types of insecure family attachment patterns, which might imply different functions of substance abuse and lead to different treatment recommendations. Methodological problems such as poor assessment of SUD and the use of different measures of attachment limit comparability. Conclusions: Although a lot of research is still needed to address the unknowns in the relation between attachment and SUD, there is strong evidence for a general link between SUD and insecure attachment. Data on connections between different patterns of attachment and different pathways towards SUD are less conclusive but mainly point to disorganized and externalizing pathways. Evidence suggests that fostering attachment security might improve the outcome of state-of-the-art approaches in both early interventional treatment and prevention. Implications for individual and family approaches are outlined.  相似文献   
90.
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