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1.

Background

Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.

Methods

Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.

Results

Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).

Conclusions

Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF.  相似文献   
2.
Attachment is a behavioral and physiological system, which enables individual’s dynamic adaptation to its environment. Attachment develops in close interaction between an infant and his/her mother, plays an important role in the development of the infant’s brain, and influences the quality of interpersonal relationships throughout life.Security of attachment is believed to influence individual response to stress, exposing insecurely organized individuals to deregulated autonomic nervous system and exaggerated hypothalamic-pituitary-adrenal activity, which, in turn, produces increased and prolonged exposure to stress-hormones. Such stress responses may have considerable implications for the development of diverse health-risk conditions, such as insulin resistance and hyperlipidemia, shown by numerous studies.Although the mechanisms are not yet fully understood, there is compelling evidence highlighting the role of psychological stress in the development of type 1 diabetes (T1D). One of the possible contributing factors for the development of T1D may be the influence of attachment security on individual stress reactivity. Thus, the suggestion is that insecurely attached individuals are more prone to experience increased and prolonged influence of stress hormones and other mechanisms causing pancreatic beta-cell destruction.The present paper opens with a short overview of the field of attachment in children, the principal attachment classifications and their historic development, describes the influence of attachment security on individual stress-reactivity and the role of the latter in the development of T1D. Following is a review of recent literature on the attachment in patients with T1D with a conclusion of a proposed role of attachment organization in the etiology of T1D.  相似文献   
3.
Purpose: To study the prevalence and time of onset of ocular complications in intermediate uveitis (IU) and to assess their effects on visual outcome in short-term and long-term follow-up.

Methods: A retrospective cohort study of patients with IU who had a minimal follow-up of one year.

Results: 96 patients (174 eyes, 70% females) were included with a mean age at presentation of 30 years. Children constituted 38% of all patients. Mean follow- up was 64.9 months. Pars planitis was the most common form followed by sarcoidosis and multiple sclerosis. Cystoid macular edema (CME), cataract, epiretinal membrane and posterior synechiae were the most prevalent complications. Posterior synechiae, band keratopathy, cataract and papillitis at presentation were associated with worse presenting visual acuity (VA). Of the late-onset complications, glaucoma/ocular hypertension (OHT) was the most significantly associated with worse long-term VA. Most sight-threatening complications (namely CME and glaucoma) were diagnosed at presentation while late complications predominantly affected the posterior segment and included among others peripheral retinal elevations, vasoproliferative tumors, and vitreous hemorrhage. Median LogMAR VA improved at short-term and long-term follow-up, from 0.2 to 0.1 (p<0.001). Subgroup analysis revealed significant VA improvement for eyes with all the different complications except for eyes with glaucoma/OHT.

Conclusion: IU is a chronic low-grade uveitis that may be associated with protean early and late complications of the anterior or posterior segments or both. Optimal treatment regimens are imperative for the strict control of inflammation and proper management of complications thus allowing a favorable long-term prognosis.  相似文献   

4.
Vinylogous (Groups III and V ) and acetylenologous (Group IV ) analogs of the classical β-adrenergic agents — stimulants and blockers — were prepared in order to evaluate the effect of degree of saturation, position of unsaturation and rigidity of the chain linking the aromatic ring and the amino containing functional group on biological activity. Derivatives from Group III , which represent 4-aryl-3-butenyl-2-ol-amine analogs of Group II , retained β1-adrenoceptor antagonist activity albeit substantially less potent (50–200-fold) than that possessed by their aryloxy counterparts. Consistent with the SAR for Group II compounds, substitution at position 2 of the aromatic ring yielded the most potent antagonists ( 5a, 5d, 5g ), with KB's ranging from 73–93 nM while 3,4-dichloro substitution ( 5e ) markedly reduced antagonist potency (KB = 2,400 nM). Agonist activity was also noted for 5b and 5d , suggesting that these compounds may be best classified as partial agonists. Representatives from Groups IV and V were inactive as antagonists at the β1-adrenoceptor confirming the importance of the spatial relationship between the hydroxyl and the amino nitrogen.  相似文献   
5.
6.
Sodium MRI of the human kidney at 3 Tesla.   总被引:6,自引:0,他引:6  
The sodium concentration gradient in the kidney (from the cortex to the medulla) serves to regulate fluid homeostasis and is tightly coupled to renal function. It was previously shown that renal function and pathophysiology can be characterized in rat kidneys by measuring the sodium gradient with (23)Na MRI. This study demonstrates for the first time the ability of (23)Na MRI to map the distribution of sodium in the human kidney and to quantify the corticomedullary sodium gradient. The study was performed on a 3T Signa LX scanner (GE) using an in-house-built quadrature surface coil. (23)Na images of volunteers were acquired using a 3D coronal gradient-echo sequence at a spatial resolution of 0.3 x 0.3 x 1.5 cm(3) in a 25-min scan time. The signal intensity (relative to the noise) increased linearly from the cortex to each of the medullae with a mean slope of 1.6 +/- 0.2 in relative arbitrary units per mm (Rel.u./mm, N = 6) and then decreased, as expected, toward the renal pelvis. Water deprivation (12 hr) induced a significant increase of 25% (P < 0.05) in this gradient. Based on these results, we suggest that sodium MRI can serve as a valuable noninvasive method for functional imaging of the human kidney.  相似文献   
7.
We have recently reported that latently HSV-2-infected guinea pigs exhibit a three- to four-fold increase in recurrent lesions after exposure to ultraviolet radiation (UV), allowing rapid evaluation of antiviral drugs in treating recurrent HSV disease. In this report we examine the effect of alpha interferon (IFN-alpha), interleukin-2 (IL-2), and a cytokine inducer (R-837) on UV-induced recurrent genital herpes. We have previously shown that topical R-837 is a biologic response modifier with no in vitro anti-HSV activity, but with potent anti-HSV activity in vivo due to cytokine induction and enhancement of cell-mediated immune responses. Three-day regimens of intravaginal R-837, or five-day intraperitoneal (i.p.) administration of IFN-alpha or of IL-2 each significantly reduced recurrent genital HSV-2 disease that occurred within 7 days of UV exposure, suggesting that cytokines or cytokine inducers may be useful in the treatment of recurrent HSV disease. This model using ultraviolet radiation to induce recurrent herpes simplex virus infection proved useful in the evaluation of immunoactive agents as putative antiviral drugs.  相似文献   
8.
PURPOSE: Epidermal growth factor receptor is expressed in pediatric malignant solid tumors. We conducted a phase I trial of gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, in children with refractory solid tumors. PATIENTS AND METHODS: Gefitinib (150, 300, 400, or 500 mg/m2) was administered orally to cohorts of three to six patients once daily continuously until disease progression or significant toxicity. Pharmacokinetic studies were performed during course one (day 1 through 28). RESULTS: Of the 25 enrolled patients, 19 (median age, 15 years) were fully evaluable for toxicity and received 54 courses. Dose-limiting toxicity was rash in two patients treated with 500 mg/m2 and elevated ALT and AST in one patient treated with 400 mg/m2. The maximum-tolerated dose was 400 mg/m2/d. The most frequent non-dose-limiting toxicities were grade 1 or 2 dry skin, anemia, diarrhea, nausea, and vomiting. One patient with Ewing's sarcoma had a partial response. Disease stabilized for 8 to > or = 60 weeks in two patients with Wilms' tumor and two with brainstem glioma (one exophytic). At 400 mg/m2, the median peak gefitinib plasma concentration was 2.2 microg/mL (range, 1.2 to 3.6 microg/mL) and occurred at a median of 2.3 hours (range, 2.0 to 8.3 hours) after drug administration. The median apparent clearance and median half-life were 14.8 L/h/m2 (range, 3.8 to 24.8 L/h/m2) and 11.7 hours (range, 5.6 to 22.8 hours), respectively. Gefitinib systemic exposures were comparable with those associated with antitumor activity in adults. CONCLUSION: Oral gefitinib is well tolerated in children. Development of the drug in combination with cytotoxic chemotherapy will be pursued.  相似文献   
9.
10.
Development, reliability, and validity of a dissociation scale   总被引:20,自引:0,他引:20  
Dissociation is a lack of the normal integration of thoughts, feelings, and experiences into the stream of consciousness and memory. Dissociation occurs to some degree in normal individuals and is thought to be more prevalent in persons with major mental illnesses. The Dissociative Experiences Scale (DES) has been developed to offer a means of reliably measuring dissociation in normal and clinical populations. Scale items were developed using clinical data and interviews, scales involving memory loss, and consultations with experts in dissociation. Pilot testing was performed to refine the wording and format of the scale. The scale is a 28-item self-report questionnaire. Subjects were asked to make slashes on 100-mm lines to indicate where they fall on a continuum for each question. In addition, demographic information (age, sex, occupation, and level of education) was collected so that the connection between these variables and scale scores could be examined. The mean of all item scores ranges from 0 to 100 and is called the DES score. The scale was administered to between 10 and 39 subjects in each of the following populations: normal adults, late adolescent college students, and persons suffering from alcoholism, agoraphobia, phobic-anxious disorders, posttraumatic stress disorder, schizophrenia, and multiple personality disorder. Reliability testing of the scale showed that the scale had good test-retest and good split-half reliability. Item-scale score correlations were all significant, indicating good internal consistency and construct validity. A Kruskal-Wallis test and post hoc comparisons of the scores of the eight populations provided evidence of the scale's criterion-referenced validity.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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