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71.
Progesterone supplementation can prevent preterm birth in some high-risk women. Progesterone binds to progesterone receptor (PR) and modulates the expression of target genes. This study investigates the association between single nucleotide polymorphisms (SNPs) in the PR gene and spontaneous preterm birth. DNA was extracted from consecutive patients with preterm birth (n = 78) and term controls (n = 415), and genotyping was performed for 3 PR SNPs (+331[G>A], + 770[C>T], +660[G>T]) using Sequenom matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Data were analyzed by chi(2) test and logistic regression analysis. Multivariate analysis showed no association between maternal carriage of minor + 331T, +770T, and/or +660T alleles and preterm birth when controlled for maternal age, ethnicity, gravidity, parity, prior preterm birth, route of delivery, or neonatal outcome. Carriage of +770T and +660T (but not +331T) was associated with preterm birth in women with a body mass index <18.5 kg/m(2) (relative risk, 10.8; 95% confidence interval, 1.4-82.6; P = .02). Maternal carriage of minor alleles of +331(G>A), +770(C>T), and +660(G> T) SNPs in the PR gene is not associated with spontaneous preterm birth.  相似文献   
72.
Uncontrolled macrophage activation is now considered to be a critical event in the pathogenesis of chronic inflammatory diseases such as atherosclerosis, multiple sclerosis, and chronic venous leg ulcers. However, it is still unclear which environmental cues induce persistent activation of macrophages in vivo and how macrophage-derived effector molecules maintain chronic inflammation and affect resident fibroblasts essential for tissue homeostasis and repair. We used a complementary approach studying human subjects with chronic venous leg ulcers, a model disease for macrophage-driven chronic inflammation, while establishing a mouse model closely reflecting its pathogenesis. Here, we have shown that iron overloading of macrophages--as was found to occur in human chronic venous leg ulcers and the mouse model--induced a macrophage population in situ with an unrestrained proinflammatory M1 activation state. Via enhanced TNF-α and hydroxyl radical release, this macrophage population perpetuated inflammation and induced a p16(INK4a)-dependent senescence program in resident fibroblasts, eventually leading to impaired wound healing. This study provides insight into the role of what we believe to be a previously undescribed iron-induced macrophage population in vivo. Targeting this population may hold promise for the development of novel therapies for chronic inflammatory diseases such as chronic venous leg ulcers.  相似文献   
73.
New anticancer drugs that target oncogenic signaling molecules have greatly improved the treatment of certain cancers. However, resistance to targeted therapeutics is a major clinical problem and the redundancy of oncogenic signaling pathways provides back-up mechanisms that allow cancer cells to escape. For example, the AKT and PIM kinases produce parallel oncogenic signals and share many molecular targets, including activators of cap-dependent translation. Here, we show that PIM kinase expression can affect the clinical outcome of lymphoma chemotherapy. We observe the same in animal lymphoma models. Whereas chemoresistance caused by AKT is readily reversed with rapamycin, PIM-mediated resistance is refractory to mTORC1 inhibition. However, both PIM- and AKT-expressing lymphomas depend on cap-dependent translation, and genetic or pharmacological blockade of the translation initiation complex is highly effective against these tumors. The therapeutic effect of blocking cap-dependent translation is mediated, at least in part, by decreased production of short-lived oncoproteins including c-MYC, Cyclin D1, MCL1, and the PIM1/2 kinases themselves. Hence, targeting the convergence of oncogenic survival signals on translation initiation is an effective alternative to combinations of kinase inhibitors.  相似文献   
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Endocrine complications of cancer therapy are reported in over 40% of childhood cancer survivors. As survival rates for childhood cancers continue to improve, both the incidence and prevalence of endocrinopathies directly related to cancer therapy will increase. To appropriately screen for and treat endocrinopathies in cancer survivors, pediatric endocrinologists must be aware of the differential pattern and severity of endocrine disturbances associated with both chemotherapy and radiation. Determining an individual child's risk for developing endocrine abnormalities requires a thorough analysis of the child's chemotherapeutic regimen, radiation dose, fractionation of radiotherapy, age during therapy, pubertal status during therapy and length of time since completion of therapy. The following review will identify endocrinopathies associated with different chemotherapy and radiation protocols and will review lifelong screening and treatment strategies for endocrine complications of childhood cancer.  相似文献   
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BACKGROUND: Asthma control has been defined clinically by using validated tools, but an asthma control scale using administrative data has not been reported. OBJECTIVE: We sought to validate a beta-agonist asthma control scale derived from administrative data. METHODS: Surveys that included validated asthma symptom and control tools were completed by a random sample of 2250 health maintenance organization members aged 18 to 56 years with persistent asthma. Linked computerized pharmacy data provided beta-agonist canister and oral corticosteroid dispensings. The proposed 4-level asthma control scale was based on the number of short-acting beta-agonist canisters dispensed in 12 months. Construct validity and predictive validity were assessed. RESULTS: For construct validity, factor analysis showed significant loading of the beta-agonist scale on the symptom control factor, and the beta-agonist scale was significantly related to the validated asthma control and symptom scales (r = 0.31, P < .0001). For predictive validity, each progressive level of the proposed beta-agonist control scale was associated with an increased risk of subsequent asthma hospitalizations or emergency department visits and oral corticosteroid use, independent of prior use. CONCLUSION: A scale based on the number of beta-agonists dispensed in a 1-year period and derived from administrative data reflects asthma symptom control over that period of time. This scale can help identify patients who are at risk for future acute asthma health care use. CLINICAL IMPLICATIONS: This information can be used in population management and by clinicians to assess long-term asthma control and identify patients who need intervention to prevent future morbidity.  相似文献   
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79.
Acute annular outer retinopathy: report of four cases   总被引:4,自引:0,他引:4  
PURPOSE: To describe the clinical findings and course in four patients with acute annular outer retinopathy. METHODS: Four patients were evaluated during the course of acute annular outer retinopathy, and the historical and clinical findings were retrospectively collected. RESULTS: Four healthy patients developed the acute onset of visual field loss associated with a localized, white annular outer retinopathy. All patients were caucasian; two were women, aged 29 and 32 years, and two were men, aged 71 and 79 years. The mean follow-up was 3.9 years (range, 1 to 6 years). On presentation, four eyes had an irregular, incomplete, peripapillary, annular band of gray-white, deep retinal opacification with visual CONCLUSIONS: These four cases of acute annular outer retinopathy expand our knowledge of this disorder. Acute annular outer retinopathy may be a distinct entity or it may represent a variant of acute zonal occult outer retinopathy retinopathy. As more cases are recognized, the characteristic features of the disease spectrum, the etiology, and treatment options may be better elucidated.  相似文献   
80.
The clinical course of four patients with visual loss in the postpartum period due to acute optic neuritis is described. Factors that disclosed the underlying etiology and expression of disease are discussed. The clinical records of four women examined and managed for visual loss after uncomplicated pregnancies and term deliveries were reviewed. Neurodiagnostic examination, treatment modalities, and outcomes were assessed. These four women with varied and confounding medical histories, all with optic neuropathy, eventually were demonstrated to harbor demyelinating disease. Although visual loss in the postpartum period evokes differential diagnostic considerations, the authors' experience suggests that puerperal immune-mediated changes are responsible for activation of optic neuritis associated with relapsing multiple sclerosis.  相似文献   
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