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Nitrate administration to enhance the detection of myocardial viability by technetium-99m tetrofosmin single-photon emission tomography 总被引:3,自引:1,他引:2
Albert Flotats Ignasi Carrió Montserrat Estorch Lluís Bernà Ana M. Catafau Carina Mart Manel Ballester 《European journal of nuclear medicine and molecular imaging》1997,24(7):767-773
A comparison was performed between technetium-99m tetrofosmin myocardial perfusion tomography at baseline and after nitrate administration, using a 2-day protocol, and rest-reinjection thallium-201 single-photon emission tomography (SPET) studies in order to assess whether nitrates enhance the detection of viable myocardium with99mTc-tetrofosmin. Fifteen patients with coronary artery disease, previous myocardial infarction and a left ventricular ejection fraction <40% underwent201T1 rest-injection and99mTc-tetrofosmin. baseline-postnitroglycerin (0.4 mg sublingually) SPET studies, within 48 h. Tomograms based on the three spatial planes were divided into 15 segments and regional tracer uptake was quantitatively analysed. Viability was defined as presence of tracer uptake >50% of peak activity on baseline studies or after reversibility. The percentage of peak activity of99mTc-tetrofosmin at baseline correlated with that of 201T1 (r=0.82,P <0.001). On baseline99mTc-tetrofosmin studies, 73 of the 225 segments that were analysed had <50% of peal. activity. Fifteen percent of these segments showed reversibility after nitrate administration, with an increase in99mTc-tetrofosmin uptake from 40%±9% to 57%±9% of peak activity (P=0.003). All reversible segments after nitrate administration had viability criteria on201Tl studies, but 20 segments that were non-viable on99mTc-tetrofosmin. studies were viable on201Tl studies. Using a threshold value of >40% of peak activity, only seven segments remained non-viable on99mTc-tetrofosmin studies. Overall agreement between99mTc-tetrofosmin with nitrates and201Tl-reinjection regarding the presence of myocardial viability was 90%. Detection of myocardial viability with99mTc-tetrofosmin. was enhanced after nitrate administration, correlating with viability criteria observed on thallium studies. 相似文献
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Relationship between adherence to inhaled corticosteroids and poor outcomes among adults with asthma
Williams LK Pladevall M Xi H Peterson EL Joseph C Lafata JE Ownby DR Johnson CC 《The Journal of allergy and clinical immunology》2004,114(6):283-1293
BACKGROUND: Regular use of inhaled corticosteroids (ICSs) can improve asthma symptoms and prevent exacerbations. However, overall adherence is poor among patients with asthma. Objective To estimate the proportion of poor asthma-related outcomes attributable to ICS nonadherence. METHODS: We retrospectively identified 405 adults age 18 to 50 years who had asthma and were members of a large health maintenance organization in southeast Michigan between January 1, 1999, and December 31, 2001. Adherence indices were calculated by using medical records and pharmacy claims. The main outcomes were the number of asthma-related outpatient visits, emergency department visits, and hospitalizations, as well as the frequency of oral steroid use. RESULTS: Overall adherence to ICS was approximately 50%. Adherence to ICS was significantly and negatively correlated with the number of emergency department visits (correlation coefficient [ R ] = -0.159), the number of fills of an oral steroid ( R = -0.179), and the total days' supply of oral steroid ( R = -0.154). After adjusting for potential confounders, including the prescribed amount of ICS, each 25% increase in the proportion of time without ICS medication resulted in a doubling of the rate of asthma-related hospitalization (relative rate, 2.01; 95% CI, 1.06-3.79). During the study period, there were 80 asthma-related hospitalizations; an estimated 32 hospitalizations would have occurred were there no gaps in medication use (60% reduction). CONCLUSIONS: Adherence to ICS is poor among adult patients with asthma and is correlated with several poor asthma-related outcomes. Less than perfect adherence to ICS appears to account for the majority of asthma-related hospitalizations. 相似文献
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Impact of intranasal budesonide on immune inflammatory responses and epithelial remodeling in chronic upper airway inflammation 总被引:3,自引:0,他引:3
Mastruzzo C Greco LR Nakano K Nakano A Palermo F Pistorio MP Salinaro ET Jordana M Dolovich J Crimi DN Vancheri C 《The Journal of allergy and clinical immunology》2003,112(1):37-44
BACKGROUND: Histologic and immunohistologic features of nasal polyps (NP) are similar to those observed in asthma, thus suggesting a similar immunopathology. OBJECTIVE: The primary objective of this study was to further understand the anti-inflammatory and immunoregulatory effects of locally delivered corticosteroids. To this end, the effect of intranasal budesonide on the expression of specific cytokines, lymphocyte subsets, and epithelial remodeling in this model of airway tissue inflammation were studied. METHODS: We used immunohistochemical techniques to examine nasal mucosae (NM) from healthy individuals and nasal polyp (NP) tissues from patients with nasal polyposis obtained before and after intranasal budesonide treatment. RESULTS: First, the density of CD8(+) cells was markedly increased in NP tissues after intranasal budesonide treatment from 16.1 +/- 8.4 (M +/- SEM) per mm(2) to 39.9 +/- 24.1. Second, the density of cells immunoreactive for IL-4, IL-5, IFN-gamma, IL-12, and TGF-beta in NP was significantly greater than in control NM tissues. The density of IL-4(+) and IL-5(+) cells in NP tissues significantly decreased after budesonide treatment from 40 +/- 12 to 17.8 +/- 8 and from 19.3 +/- 11 to 10.4 +/- 7, respectively. In contrast, the density of IFN-gamma(+) and IL-12(+) cells remained unchanged. In addition, we found that the density of TGF-beta(+) cells significantly increased after intranasal budesonide from 18 +/- 5 to 41 +/- 9. Third, damage to the entire length of the NP epithelium was quantified using a grading system. The epithelium of untreated NP was substantially damaged; remarkable epithelial restitution with no apparent changes in stromal collagen deposition was observed after intranasal budesonide treatment. CONCLUSIONS: These findings demonstrate that intranasal budesonide induced an increase in CD8 population and a selective regulatory effect on tissue cytokine expression. Furthermore, intranasal budesonide promoted epithelial remodeling. We hypothesize that these immunoregulatory and remodeling effects elicited by steroids might be, at least in part, mediated by the induction of TGF-beta. 相似文献
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Immunohistochemical classification of non-BRCA1/2 tumors identifies different groups that demonstrate the heterogeneity of BRCAX families. 总被引:1,自引:0,他引:1
Emiliano Honrado Ana Osorio Roger L Milne María F Paz Lorenzo Melchor Alberto Cascón Miguel Urioste Alicia Cazorla Orland Díez Enrique Lerma Manel Esteller José Palacios Javier Benítez 《Modern pathology》2007,20(12):1298-1306
Around 25% of hereditary breast and ovarian cancer families have mutations in the BRCA1 and BRCA2 genes. The search for other genes has until now failed, probably because there is not one single BRCAX gene, but rather various genes that may each be responsible for a small number of breast cancer families and/or may interact according to a polygenic model. We have studied 50 tumors from probands belonging to non-BRCA1/2 breast cancer families (BRCAX), using 25 immunohistochemical markers. The objective was to classify these tumors and confirm that they are heterogeneous. Unsupervised cluster analysis showed the existence of the following two main groups of tumors: high-grade and estrogen receptor (ER)-negative tumors (50%), and low-grade and ER-positive tumors (50%). In addition we identified five subgroups, three among the high-grade and two among the low-grade groups; one overexpressing HER-2 (18%); one with a basal-like phenotype (14%); one with a normal breast-like phenotype (18%); a luminal A subgroup (36%), and a luminal B subgroup (14%). Hypermethylation of the BRCA1 gene was observed in 42% of the cases, spread across all five subgroups, but only 37% of those had loss of heterozygosity as well. These latter cases were all clustered in the high-grade group and the majority of them in the basal-like subgroup. Our results show that familial non-BRCA1/2 tumors are heterogeneous and suggest a polygenic model for explaining the majority of BRCAX families. In addition we have defined a subset of them that have somatic inactivation of the BRCA1 gene. 相似文献
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Williams LK Peterson EL Pladevall M Tunceli K Ownby DR Johnson CC 《The Journal of allergy and clinical immunology》2005,116(1):102-108
BACKGROUND: Early childhood fevers appear to protect against later allergies and asthma. What is not known is the time in which fevers exert this effect and whether the degree of temperature increase is important. OBJECTIVE: We sought to examine the relationship between the time and degree of early fevers and later allergies and asthma. METHODS: Eight hundred thirty-five children from southeast Michigan were enrolled at birth. Clinic records from their first 2 years were abstracted for episodes of fever. At age 6 to 7 years, children underwent allergy testing. We examined fevers occurring within 6-month intervals in the first 2 years of life and outcomes at age 6 to 7 years. The primary outcome measures were allergic sensitization, asthma, asthma with allergic sensitization, and asthma without allergic sensitization. RESULTS: In the unadjusted analysis each episode of fever between 7 and 12 months of age was associated with a lower odds of allergic sensitization (odds ratio [OR], 0.71; 95% CI, 0.54-0.93) and asthma with allergic sensitization (OR, 0.43; 95% CI, 0.21-0.90) at age 6 to 7 years. Likewise, every 1 degrees C increase in the maximum temperature between 7 and 12 months was associated with a lower odds of allergic sensitization (OR, 0.77; 95% CI, 0.61-0.96) and asthma with allergic sensitization (OR, 0.62; 95% CI, 0.40-0.94). After adjusting for potential confounders, each episode of fever between 7 and 12 months was associated with a lower likelihood of asthma with allergic sensitization (adjusted OR, 0.33; 95% CI, 0.11-0.94) at age 6 to 7 years. CONCLUSIONS: Both the timing and intensity of childhood fevers appear to be important factors in the development of allergies and asthma. 相似文献
10.
Jaume Alijotas-Reig Manel Casellas-Caro Raquel Ferrer-Oliveras Elisa Llurba-Olive Eduard Hermosilla Miquel Vilardell-Tarres Lluis Cabero-Roura 《American journal of reproductive immunology (New York, N.Y. : 1989)》2008,60(3):229-237
Problem Anti-beta2 -Glicoprotein-1 antibodies (anti-β2 GPI-ab) have been related to recurrent miscarriage (RM) with conflicting results. The aim was to evaluate the role of anti-β2 -GPI-ab as unique biological marker in RM related to antiphospholipid (aPL).
Method of study A cohort study that included 59 cases, divided in two groups, was designed: group 1 comprised 43 pregnant women with 'obstetric' antiphospholipid syndrome (APS) and group 2 included 16 cases with similar complaints but only having repeatedly anti-β2 -GPI-ab. Previous thrombosis and/or inherited thrombophilia were excluded. Lupus anticoagulant, anticardiolipin antibodies (aCA), anti-β2 -GPI-ab, and other autoantibodies were analyzed. Miscarriages, premature births, pre-eclampsia, live births, placental and systemic thromboses were studied.
Results No differences in previous obstetric complications were detected ( P = 1.00–0.164). After the treatment, differences in number of obstetric complications were not seen ( P = 1.00). Live births were similar in two groups (88.4% and 93.7%; P = 1.00). Placental thrombosis was equal in both groups, 93.3% versus 80% ( P = 1.00).
Conclusion These results suggest that anti-β2 -GPI-ab may be considered a biological marker for obstetric APS. 相似文献
Method of study A cohort study that included 59 cases, divided in two groups, was designed: group 1 comprised 43 pregnant women with 'obstetric' antiphospholipid syndrome (APS) and group 2 included 16 cases with similar complaints but only having repeatedly anti-β
Results No differences in previous obstetric complications were detected ( P = 1.00–0.164). After the treatment, differences in number of obstetric complications were not seen ( P = 1.00). Live births were similar in two groups (88.4% and 93.7%; P = 1.00). Placental thrombosis was equal in both groups, 93.3% versus 80% ( P = 1.00).
Conclusion These results suggest that anti-β