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61.
Ligase IV syndrome is a rare differential diagnosis for Nijmegen breakage syndrome owing to a shared predisposition to lympho‐reticular malignancies, significant microcephaly, and radiation hypersensitivity. Only 16 cases with mutations in LIG4 have been described to date with phenotypes varying from malignancy in developmentally normal individuals, to severe combined immunodeficiency and early mortality. Here, we report the identification of biallelic truncating LIG4 mutations in 11 patients with microcephalic primordial dwarfism presenting with restricted prenatal growth and extreme postnatal global growth failure (average OFC ?10.1 s.d., height ?5.1 s.d.). Subsequently, most patients developed thrombocytopenia and leucopenia later in childhood and many were found to have previously unrecognized immunodeficiency following molecular diagnosis. None have yet developed malignancy, though all patients tested had cellular radiosensitivity. A genotype–phenotype correlation was also noted with position of truncating mutations corresponding to disease severity. This work extends the phenotypic spectrum associated with LIG4 mutations, establishing that extreme growth retardation with microcephaly is a common presentation of bilallelic truncating mutations. Such growth failure is therefore sufficient to consider a diagnosis of LIG4 deficiency and early recognition of such cases is important as bone marrow failure, immunodeficiency, and sometimes malignancy are long term sequelae of this disorder.  相似文献   
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To examine the associations among social-emotional support, life satisfaction, and mental health with not having a routine checkup among women of reproductive age in the US, data from the 2009 Behavioral Risk Factor Surveillance System, a population-based telephone survey of health behaviors, were analyzed among reproductive aged (18–44 years) women in the US. Prevalence estimates were calculated for not having a routine checkup in the past year with measures of social-emotional support, life satisfaction, and mental distress. Independent multivariable logistic regressions for each measure assessed not having a routine checkup within the past year with adjustment for age, race/ethnicity, education level, and health care coverage. Among women of reproductive age, 33.7 % (95 % CI 33.0–34.4) did not have a routine checkup within the past year. Factors associated with not having a routine checkup included: having social-emotional support most of the time (AOR = 1.29, 95 % CI 1.20–1.38) or sometimes or less (AOR = 1.47, 95 % CI 1.34–1.61) compared to those who reported always having the social-emotional support they need; reporting life satisfaction as being satisfied (AOR = 1.27, 95 % CI 1.19–1.36) or dissatisfied (AOR = 1.65, 95 % CI 1.43–1.91) compared to being very satisfied; and frequent mental distress (AOR = 1.19, 95 % CI 1.09–1.30) compared to those without. Women who report lower levels of social-emotional support, less life satisfaction, and frequent mental distress are less likely to see a doctor for a routine checkup. Targeted outreach that provides appropriate support are needed so these women can access clinical services to increase exposure to preventive health opportunities and improve overall health.  相似文献   
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Blepharochalasis is a rare disorder of unknown etiology defined by loose, atrophic periorbital skin following recurrent episodes of eyelid edema. Characteristic histopathology shows complete absence of elastic fibers. The current case progressed after multiple episodes of crying, which may be related to matrix metalloproteinase dysregulation. This case offers further insights into the possible pathogenesis of blepharochalasis, paving the way for more targeted, disease‐modifying therapies.  相似文献   
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The regulation of metal ion transport within neurons is critical for normal brain function. Of particular importance is the regulation of redox metals such as iron (Fe), where excess levels can contribute to oxidative stress and protein aggregation, leading to neuronal death. The divalent metal transporter 1 (DMT1) plays a central role in the regulation of Fe as well as other metals; hence, failure of DMT1 regulation is linked to human brain pathology. However, it remains unclear how DMT1 is regulated in the brain. Here, we show that DMT1 is regulated by Ndfip1 (Nedd4 family-interacting protein 1), an adaptor protein that recruits E3 ligases to ubiquitinate target proteins. Using human neurons we show the Ndfip1 is upregulated and binds to DMT1 in response to Fe and cobalt (Co) exposure. This interaction results in the ubiquitination and degradation of DMT1, resulting in reduced metal entry. Induction of Ndfip1 expression protects neurons from metal toxicity, and removal of Ndfip1 by shRNAi results in hypersensitivity to metals. We identify Nedd4–2 as an E3 ligase recruited by Ndfip1 for the ubiquitination of DMT1 within human neurons. Comparison of brains from Ndfip1−/− with Ndfip1+/+ mice exposed to Fe reveals that Ndfip1−/− brains accumulate Fe within neurons. Together, this evidence suggests a critical role for Ndfip1 in regulating metal transport in human neurons.  相似文献   
67.
A focused oligonucleotide microarray featuring 62 probes targeting strain variable regions of the Clostridium botulinum strain ATCC 3502 genome sequence was developed to differentiate C. botulinum type A strains. The strain variable regions were selected from deletions identified among a panel of 10 type A strains compared to the strain ATCC 3502 genome sequence using high density comparative genomic hybridization microarrays. The focused microarray also featured specific probes for the detection of the neurotoxin genes of various serotypes (A–G), toxin gene cluster components (ha70 and orfX1), and fldB as a marker for proteolytic clostridia (Group I). Eight pairs of strains selected from separate type A botulism outbreaks were included in the 27 subtype A1–A4 strains examined in this study. Each outbreak related strain pair consisted of strains isolated from different sources (stool and food). Of the eight outbreak related strain pairs, six groups of strains with indistinguishable hybridization patterns were identified. Outbreak related strains were shown to have identical hybridization patterns. Strain pairs from three separate outbreaks involving strains harboring both the type A neurotoxin gene (bont/A) and an unexpressed type B neurotoxin gene (bont/B) shared the same probe hybridization profile. The focused microarray format provides a rapid approach for neurotoxin gene detection and preliminary determination of the relatedness of strains isolated from different sources.  相似文献   
68.
The discovery of a new class of effective migraine-abortive medications, the triptans, has sparked a new interest in the study of vascular headache. Over the past few years, the Food and Drug Administration (FDA) has approved six new abortive pharmacologic therapies, with several others in various stages of clinical trials. Unfortunately, concurrent pharmacologic changes in headache prophylaxis have not kept pace with their abortive counterparts. However, divalproex sodium (Depakote), which is approved by the FDA as a migraine prophylactic agent, is the first in the anticonvulsant class of medication for migraine headache and has expanded the options in headache treatment. The objective of this retrospective multicenter study of 284 patients with migraine or cluster headaches was to examine the clinical efficacy and safety of divalproex sodium as prophylaxis in monotherapy and in polytherapy. Sixty-one percent of migraineurs and 73% of cluster patients noted a decrease in pain with divalproex sodium and continued that therapy for more than 3 months. Reported negative side effects included weight gain, nausea, somnolence, tremor, alopecia, dysequilibrium, and rash. However, only 14% of subjects discontinued therapy due to these side effects. Overall, divalproex sodium was found to be an effective and generally well-tolerated prophylactic treatment option as monotherapy or in polytherapy for migraine and cluster headache.  相似文献   
69.
He L  Pappan LK  Grenache DG  Li Z  Tollefsen DM  Santoro SA  Zutter MM 《Blood》2003,102(10):3652-3657
The alpha 2 beta 1 integrin serves as a receptor for collagens, laminin, and several other nonmatrix ligands. Many studies have suggested that the alpha 2 beta 1 integrin is a critical mediator of platelet adhesion to collagen within the vessel wall after vascular injury and that the interactions of the platelet alpha 2 beta 1 integrin with subendothelial collagen after vascular injury are required for proper hemostasis. We have used the alpha 2 beta 1 integrin-deficient mouse to evaluate the contributions of the alpha 2 beta 1 integrin in 2 in vivo models of thrombosis. Studies using a model of endothelial injury to the carotid artery reveal that the alpha 2 beta 1 integrin plays a critical role in vascular thrombosis at the blood-vessel wall interface under flow conditions. In contrast, the alpha 2 beta 1 integrin is not required for the formation of thrombi and pulmonary emboli following intravascular injection of collagen. Our results are the first to document a critical in vivo role for the alpha 2 beta 1 integrin in thrombus formation at the vessel wall under conditions of shear following vascular injury.  相似文献   
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