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The factor V Leiden mutation in 12 children with thrombosis and in 20 controls was investigated. Five heterozygous individuals and 1 homozygous individual among the cases with thrombosis and 1 heterozygous individual among controls were found. Central nervous system thromboses were increased in children with the factor V mutation, associated with protein S deficiency. © 1996 Wiley-Liss, Inc.  相似文献   
104.
Nuclear noncoding RNAs (ncRNAs) are key regulators of gene expression and chromatin organization. The progress in studying nuclear ncRNAs depends on the ability to identify the genome-wide spectrum of contacts of ncRNAs with chromatin. To address this question, a panel of RNA–DNA proximity ligation techniques has been developed. However, neither of these techniques examines proteins involved in RNA–chromatin interactions. Here, we introduce RedChIP, a technique combining RNA–DNA proximity ligation and chromatin immunoprecipitation for identifying RNA–chromatin interactions mediated by a particular protein. Using antibodies against architectural protein CTCF and the EZH2 subunit of the Polycomb repressive complex 2, we identify a spectrum of cis- and trans-acting ncRNAs enriched at Polycomb- and CTCF-binding sites in human cells, which may be involved in Polycomb-mediated gene repression and CTCF-dependent chromatin looping. By providing a protein-centric view of RNA–DNA interactions, RedChIP represents an important tool for studies of nuclear ncRNAs.  相似文献   
105.
Discoid lupus erythematosus (DLE) is a chronic inflammatory erythematous skin disease that can be triggered by several factors. Rosacea is another skin disease that causes facial redness and tenderness. Demodex mites have been reported in rosacea and DLE patients commonly in the literature. These two diseases can be seen concomitant, mimic each other clinically and share common possible etiologic factors. To assess demodex mite infestation in both clinical and histopathological findings in DLE patients. We retrospectively evaluated the files of 42 patients with DLE who had been diagnosed DLE based on clinical and histopathological findings between August 2018 and August 2019. Demodex positivity was detected 50% of patients (n = 21). Neutrophile percentages in the dermal and perivascular area were higher in the demodex positive patients (4.43%) than in the Demodex negative patients (2.19%). The intensity of demodex mites correlated positively with dermal neutrophile percentages. ANA was negative in 29 patients (69%) and positive in 13 patients (31%). Anti‐dsDNA was negative in serology and follicular plugging was positive in histopathology in all 42 patients (100%). This was a retrospective study. DLE and rosacea share common features in etiopathogenesis and clinical presentation. Inflammation and exacerbations caused by the demodex mites may increase the clinical severity of DLE. Although the position of demodex mites in DLE etiopathogenesis is not known exactly, the presence of high demodex in DLE patients has been determined. Standard skin surface biopsy can be a routine procedure for the evaluation of DLE patients in daily clinical practice.  相似文献   
106.
Fatal pulmonary edema and hemorrhage are significant complications of endovascular treatment in steno-occlusive carotid artery disease; a rational mechanism has not been adequately examined in the literature so far. We investigated if cervical sympathetic ganglia ischemia prevents pulmonary vasospasm on the prognosis of bilateral common carotid artery ligation (BCCAL). Twenty-three adult New Zealand rabbits (4.2 ± 0.3 kg) were randomly divided into three groups: the control group (G1, n = 5), the sham group (G2, n = 6), and the BCCAL group (G3, n = 12). Common carotid arteries were dissected bilaterally in G2/G3, and permanent BCCAL was applied to only in G3. All animals were followed for 3 weeks and decapitated under general anesthesia. Histopathological changes in stellate ganglia and severity of pulmonary vasospasm-related lung edema and hemorrhage were investigated. Results were analyzed by the Kruskal–Wallis test. Two animals of G3 dead within three weeks and the remainder were sacrificed three weeks later. Subpleural petechial foci and an endotracheal bloody fluid collection were grossly observed in the lungs. Histopathologically, pulmonary artery vasospasm, perivascular and subintimal edema, interalveolar hemorrhage, and alveolar wall destructions were observed with less ischemic-degenerated neuron density-determined stellate ganglia animals. Neurodegeneration of stellate ganglia may have a beneficial effect on the prevention of lung injury during steno-occlusive carotid artery disease.  相似文献   
107.
Small molecules can have a significant effect on human metabolic processes. Computational drug design aims at constructing specialized small molecules that selectively and efficiently address specific proteins. The basic ideas of computational molecular design are presented and it will be shown how a virtual protein can be computer designed. This virtual protein can be used to predict the binding affinity of given small molecules without having to synthesize them in a laboratory. Modern computational drug design goes far beyond the lock and key principle. Possible future developments are discussed and a current successful example of computational drug design in the field of painkiller medication is demonstrated.  相似文献   
108.
In patients with vitiligo, the clinical and laboratory features of the disease may vary according to time of onset. This is addressed in the literature by only a few studies with conflicting results. The aim of this study was to determine the demographic and clinical features of patients with non‐segmental vitiligo and to establish the association between vitiligo and autoimmune diseases with a focus on time of disease onset. A total of 224 vitiligo patients for whom complete medical records were available were evaluated retrospectively. Demographic data, scores on the Vitiligo Area Score Index (VASI), clinical features, vitiligo disease activity, repigmentation status, presence of any accompanying autoimmune disease, antinuclear antibody (ANA) titers, serum levels of glucose, thyroid‐stimulating hormone (TSH), thyroxine (T4) hormone, anti‐thyroid peroxidase (anti‐TPO), and anti‐thyroglobulin (anti‐TG) were recorded. The prevalence of halo nevi was significantly higher (P < 0.001) among children than in other patient groups. The prevalence of leukotrichia was higher in adults with adult‐onset disease than in either pediatric patients or adults with childhood‐onset disease (P = 0.002). Both anti‐TG and anti‐TPO levels were significantly higher in adults with adult‐onset disease than in pediatric patients and adult patients with childhood‐onset disease. The prevalence of autoimmune disease was 22.2%. Anti‐TG levels were significantly higher in patients with treatment‐related repigmentation than in those without repigmentation. This study shows that clinical features and associations with autoimmune disease may vary according to the age of onset of vitiligo.  相似文献   
109.
The aim of our study was to determine whether fluid-attenuated inversion recovery (FLAIR) imaging and diffusion-weighted imaging (DWI) would be helpful in characterizing primitive neuroectodermal tumors (PNET) from other pediatric brain tumors. We expected that the compact cellular nature and the relatively small extracellular space of this tumor would affect the signal intensity on both pulse sequences relative to the more sparsely cellular glial tumors that have larger extracellular spaces. Eighteen pediatric patients with PNET were examined on a 1.5 T MRI with routine imaging plus FLAIR and compared with 28 patients with non-PNET. DWI was also performed in 7 PNET and 18 non-PNET. Seventy-eight percent of PNET were isointense to gray matter on FLAIR while 82 % of non-PNET were hyperintense and only one was isointense (3 %). Diffusion was abnormally restricted in all 7 PNET examined (100 %) but was restricted in non-PNET in only 1 out of 18 (6 %) patients who had DWI. The differences in the histologic architecture between PNET and non-PNET are reflected in both FLAIR imaging and in DWI. Received: 3 February 2001/Accepted: 13 February 2001  相似文献   
110.
Behçet disease is a multisystemic chronic autoimmune process that can be responsible for some vascular lesions, in addition to its typical dermatologic lesions. Arterial pseudoaneurysm formation can be diagnosed in this group of patients and generally surgery is indicated. In this report, we discuss an alternative endovascular intervention and its advantages. An endovascular stent graft was placed in the popliteal artery pseudoaneurysm of a 37-year-old male with Behçet disease. Early results of this procedure are good thus far. Implantation of an endovascular stent graft, an alternative modality in the treatment of pseudoaneurysms, can result in a shorter hospital stay and a significantly shorter period before returning to normal life. General anesthesia and surgical dissection are avoided, thus diminishing morbidity.  相似文献   
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