Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
1.
J Neurointerv Surg ; 8(1): 94-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25387731

RESUMO

BACKGROUND AND PURPOSE: Implanted, actual flow diverter pore density is thought to be strongly influenced by proper matching between the device size and parent artery diameter. The objective of this study was to characterize the correlation between device sizing, metal coverage, and the resultant occlusion of aneurysms following flow diverter treatment in a rabbit model. METHODS: Rabbit saccular aneurysms were treated with flow diverters (iso-sized to proximal parent artery, 0.5 mm oversized, or 1.0 mm oversized, respectively, n=6 for each group). Eight weeks after implantation, the angiographic degree of aneurysm occlusion was graded (complete, near-complete, or incomplete). The ostium of the explanted aneurysm covered with the flow diverter struts was photographed. Based on gross anatomic findings, the metal coverage and pore density at the ostium of the aneurysm were calculated and correlated with the degree of aneurysm occlusion. RESULTS: Angiographic results showed there were no statistically significant differences in aneurysm geometry and occlusion among groups. The mean parent artery diameter to flow diverter diameter ratio was higher in the 1.0 mm oversized group than in the other groups. Neither the percentage metal coverage nor the pore density showed statistically significant differences among groups. Aneurysm occlusion was inversely correlated with the ostium diameter, irrespective of the size of the device implanted. CONCLUSIONS: Device sizing alone does not predict resultant pore density or metal coverage following flow diverter implantation in the rabbit aneurysm model. Aneurysm occlusion was not impacted by either metal coverage or pore density, but was inversely correlated with the diameter of the ostium.


Assuntos
Prótese Vascular/normas , Circulação Cerebrovascular/fisiologia , Procedimentos Endovasculares/instrumentação , Aneurisma Intracraniano/terapia , Animais , Implante de Prótese Vascular , Modelos Animais de Doenças , Procedimentos Endovasculares/métodos , Coelhos
2.
J Thorac Imaging ; 31(1): 2-10, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26447872

RESUMO

PURPOSE: The aim of the study was to assess whether magnetic resonance imaging (MRI) characteristics can distinguish benign from malignant part-solid pulmonary nodules and predict the aggressiveness of the latter. We also sought to compare MRI-derived parameters with morphologic and physiological values derived from conventional examinations such as computed tomography and positron emission tomography/computed tomography. MATERIALS AND METHODS: This was an institutional review board-approved pilot study of 28 participants (23 women, mean age 73.5±13.8 y) with 32 biopsy-proven lesions. 3-T unenhanced pulmonary MRI examinations were performed with regions of interest drawn around lesions for T1, T2, T2*, and diffusion-weighted sequences. Apparent diffusion coefficient (ADC) and T2* values were calculated. Two weeks later the regions of interest were redrawn. MRI parameters were compared with lesion pathology, maximal standard uptake value (SUVmax), and Hounsfield units (HU). MRI lesion visibility was correlated with solid component size and the percentage of solid component. Intraobserver and interobserver agreements were determined. RESULTS: Only ADC values correlated with malignancy (P<0.05). ADC≥1.28 µm/ms predicted malignancy with 83.3% sensitivity (area under the curve 0.79). ADC and T2* correlated with adenocarcinoma subtypes (P<0.05). No MRI parameters predicted tumor differentiation (P>0.11). SUVmax did not correlate with any MRI parameters (P>0.56). Visibility on T1-weighted images correlated with the percentage of solid components (P<0.03). T1 and T2 values showed significant correlation with HU measurements of the entire nodule (P<0.001 and P<0.024, respectively) and HU measurements of solid components (P=0.031 and 0.008, respectively). CONCLUSIONS: 3 T MRI with quantitative ADC values demonstrated potential for discriminating benign part-solid pulmonary nodules from malignant lesions. ADC and T2* values correlated with adenocarcinoma subtypes. No MRI parameters correlated with SUVmax. T1 and T2 values showed significant correlation with HU measurements of the entire nodule and of the solid components.


Assuntos
Neoplasias Pulmonares/patologia , Imageamento por Ressonância Magnética , Nódulos Pulmonares Múltiplos/patologia , Nódulo Pulmonar Solitário/patologia , Idoso , Feminino , Humanos , Pulmão/patologia , Masculino , Projetos Piloto , Estudos Prospectivos , Reprodutibilidade dos Testes
3.
J Med Imaging (Bellingham) ; 2(2): 026001, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26158114

RESUMO

Determining whether glioblastoma multiforme (GBM) is progressing despite treatment is challenging due to the pseudoprogression phenomenon seen on conventional MRIs, but relative cerebral blood volume (CBV) has been shown to be helpful. As CBV's calculation from perfusion-weighted images is not standardized, we investigated whether there were differences between three FDA-cleared software packages in their CBV output values and subsequent performance regarding predicting survival/progression. Forty-five postradiation therapy GBM cases were retrospectively identified as having indeterminate MRI findings of progression versus pseudoprogression. The dynamic susceptibility contrast MR images were processed with different software and three different relative CBV metrics based on the abnormally enhancing regions were computed. The intersoftware intraclass correlation coefficients were 0.8 and below, depending on the metric used. No statistically significant difference in progression determination performance was found between the software packages, but performance was better for the cohort imaged at 3.0 T versus those imaged at 1.5 T for many relative CBV metric and classification criteria combinations. The results revealed clinically significant variation in relative CBV measures based on the software used, but minimal interoperator variation. We recommend against using specific relative CBV measurement thresholds for GBM progression determination unless the same software or processing algorithm is used.

4.
Diabetes Technol Ther ; 17(8): 587-95, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26121060

RESUMO

BACKGROUND: Understanding the effect size, variability, and underlying physiology of the dawn phenomenon is important for next-generation closed-loop control algorithms for type 1 diabetes (T1D). SUBJECTS AND METHODS: We used an iterative protocol design to study 16 subjects with T1D on individualized insulin pump therapy for two successive nights. Endogenous glucose production (EGP) rates at 3 a.m. and 7 a.m. were measured with [6,6-(2)H(2)]glucose as a single tracer, infused from midnight to 7 a.m. in all subjects. To explore possibility of tracer recycling due to prolonged [6,6-(2)H(2)]glucose infusion, which was highly probable after preplanned interim data analyses, we infused a second tracer, [6-(3)H]glucose, from 4 a.m. to 7 a.m. in the last seven subjects to measure EGP at 7 a.m. RESULTS: Cortisol concentrations increased during both nights, but changes in glucagon and insulin concentration were inconsistent. Although the plasma glucose concentrations rose from midnight to 7 a.m. during both nights, EGP measured with [6,6-(2)H(2)]glucose between 3 a.m. and 7 a.m. did not differ during Night 1 but fell in Night 2. However, EGP measured with [6-(3)H]glucose at 7 a.m. was higher than that measured with [6,6-(2)H(2)]glucose during both nights, thereby suggesting tracer recycling probably underestimating EGP calculated at 7 a.m. with [6,6-(2)H(2)]glucose. Likewise, EGP was higher at 7 a.m. with [6-(3)H]glucose than at 3 a.m. with [6,6-(2)H(2)]glucose during both nights. CONCLUSIONS: The data demonstrate a consistent overnight rise in glucose concentrations through increased EGP, mediated likely by rising cortisol concentrations. The observations with the dual tracer approach imply significant tracer recycling leading to underestimation of EGP measured by longer-duration tracer infusion.


Assuntos
Automonitorização da Glicemia/métodos , Glicemia/metabolismo , Ritmo Circadiano/fisiologia , Diabetes Mellitus Tipo 1/sangue , Adulto , Feminino , Glucagon/sangue , Humanos , Hidrocortisona/sangue , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Sono/fisiologia
5.
J Am Coll Radiol ; 12(5): 444-52, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25940362

RESUMO

PURPOSE: Out-of pocket expenses for common medical tests and procedures will become increasingly relevant as high-deductible insurance plans gain widespread adoption. The purpose of this study was to determine the variability of pricing for an outpatient, noncontrast knee MRI, based on geographic location and population. METHODS: We randomly chose nonhospital outpatient radiology centers in each state's highest-population locality, based on a list generated from the ACR MRI Accreditation Program database. The presence of ≥2 and a maximum of 3 centers within a given locality was required for inclusion. Using a standardized script, we contacted centers by phone to determine the lowest, out-of-pocket, bundled cost (technical fee plus professional fee). The median (interquartile range) costs were calculated within each locality and region, including Midwest, Northeast, South, and West regions. A generalized linear model and Spearman's rank correlation were used to determine the association between cost and region, and cost and population, respectively. RESULTS: A total of 122 outpatient centers from 43 cities were analyzed. Costs ranged from $259 to $2,042 across all centers. For centers within a locality, the difference between the minimum and maximum costs among centers ranged from $1,592 to $0; median cost differences between localities ranged from $1,488 to $325. Median cost for the West, Northeast, Midwest, and South region was $690, $500, $550, and $550, respectively (P = .849). Median cost was inversely correlated with population density (ρ = -0.417 [correlation coefficient], P = .005). CONCLUSIONS: Out-of-pocket costs for an outpatient knee MRI vary substantially across imaging centers, both locally and nationally. Cost tends to decrease with increasing local population.


Assuntos
Instituições de Assistência Ambulatorial/economia , Assistência Ambulatorial/economia , Diagnóstico por Imagem/economia , Gastos em Saúde/estatística & dados numéricos , Radiologia/economia , Assistência Ambulatorial/estatística & dados numéricos , Instituições de Assistência Ambulatorial/estatística & dados numéricos , Custos e Análise de Custo/estatística & dados numéricos , Diagnóstico por Imagem/estatística & dados numéricos , Análise Espacial , Estados Unidos/epidemiologia
6.
Am J Physiol Endocrinol Metab ; 308(12): E1106-15, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25898950

RESUMO

To determine the effects of exercise on postprandial glucose metabolism and insulin action in type 1 diabetes (T1D), we applied the triple tracer technique to study 16 T1D subjects on insulin pump therapy before, during, and after 75 min of moderate-intensity exercise (50% V̇o2max) that started 120 min after a mixed meal containing 75 g of labeled glucose. Prandial insulin bolus was administered as per each subject's customary insulin/carbohydrate ratio adjusted for meal time meter glucose and the level of physical activity. Basal insulin infusion rates were not altered. There were no episodes of hypoglycemia during the study. Plasma dopamine and norepinephrine concentrations rose during exercise. During exercise, rates of endogenous glucose production rose rapidly to baseline levels despite high circulating insulin and glucose concentrations. Interestingly, plasma insulin concentrations increased during exercise despite no changes in insulin pump infusion rates, implying increased mobilization of insulin from subcutaneous depots. Glucagon concentrations rose before and during exercise. Therapeutic approaches for T1D management during exercise will need to account for its effects on glucose turnover, insulin mobilization, glucagon, and sympathetic response and possibly other blood-borne feedback and afferent reflex mechanisms to improve both hypoglycemia and hyperglycemia.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Exercício Físico/fisiologia , Insulina/metabolismo , Período Pós-Prandial , Adolescente , Adulto , Idoso , Diabetes Mellitus Tipo 1/tratamento farmacológico , Teste de Esforço , Feminino , Esvaziamento Gástrico , Humanos , Insulina/administração & dosagem , Sistemas de Infusão de Insulina , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
AJR Am J Roentgenol ; 204(3): W363-70, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25714323

RESUMO

OBJECTIVE. The purposes of this study were to describe the prevalence of background parenchymal uptake categories observed at screening molecular breast imaging (MBI) and to examine the association of background parenchymal uptake with mammographic density and other clinical factors. MATERIALS AND METHODS. Adjunct MBI screening was performed for women with dense breasts on previous mammograms. Two radiologists reviewed images from the MBI examinations and subjectively categorized background parenchymal uptake into four groups: photopenic, minimal-mild, moderate, or marked. Women with breast implants or a personal history of breast cancer were excluded. The association between background parenchymal uptake categories and patient characteristics was examined with Kruskal-Wallis and chi-square tests as appropriate. RESULTS. In 1149 eligible participants, background parenchymal uptake was photopenic in 252 (22%), minimal-mild in 728 (63%), and moderate or marked in 169 (15%). The distribution of categories differed across BI-RADS density categories (p < 0.0001). In 164 participants with extremely dense breasts, background parenchymal uptake was photopenic in 72 (44%), minimal-mild in 55 (34%), and moderate or marked in 37 (22%). The moderate-marked group was younger on average, more likely to be premenopausal or perimenopausal, and more likely to be using postmenopausal hormone therapy than the photopenic or minimal-mild groups (p < 0.0001). CONCLUSION. Among women with similar-appearing mammographic density, background parenchymal uptake ranged from photopenic to marked. Background parenchymal uptake was associated with menopausal status and postmenopausal hormone therapy but not with premenopausal hormonal contraceptives, phase of menstrual cycle, or Gail model 5-year risk of breast cancer. Additional work is necessary to fully characterize the underlying cause of background parenchymal uptake and determine its utility in predicting subsequent risk of breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Glândulas Mamárias Humanas/anormalidades , Imagem Molecular , Densidade da Mama , Feminino , Humanos , Pessoa de Meia-Idade , Cintilografia , Estudos Retrospectivos
8.
Neurosurgery ; 76(3): 337-43; discussion 343, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25599211

RESUMO

BACKGROUND: Intracranial dolichoectasia is associated with high morbidity, and its pathophysiology remains poorly understood. OBJECTIVE: To develop a technique for the creation of a murine model of dolichoectasia. METHODS: C57/BL6 mice were injected with 0 milliunit (mu) (control, n = 5), 15 mu (n = 7), 25 mu (n = 10), 35 mu (n = 10), and 55 mu (n = 6) of elastase in the cisterna magna. Fourteen days after injection, the vasculature of the brain was perfused with MicroFil polymerizing compound. Tortuosity index and the percentage increase in arterial diameter were calculated for the basilar artery, posterior communicating arteries, and the A1 segment of the anterior cerebral arteries. Tortuosity index >10 combined with 25% increase in diameter were used to indicate success in achieving dolichoectasia. RESULTS: The mortality rate was 28%, 30%, 80%, and 83% in the 15, 25, 35, and 55 mu groups, respectively. As the 35 and 55 mu groups experienced unacceptable mortality rates, they were excluded from further analysis. The tortuosity index and percent increase arterial diameter of the 15 and 25 mu groups for the left anterior cerebral arteries, right anterior cerebral arteries, left posterior communicating arteries, right posterior communicating arteries, and basilar artery were significantly higher (TI >10 and arterial diameter >25%) than in the control. There was no significant difference in tortuosity index or artery diameter between the 15 and 25 mu groups for any of the 5 artery segments. CONCLUSION: Elastase injection through the cisterna magna can induce intracranial dolichoectasia in mice. Fifteen to 25 mu of elastase is an appropriate dose to use with acceptable mortality.


Assuntos
Modelos Animais de Doenças , Elastase Pancreática/toxicidade , Insuficiência Vertebrobasilar , Animais , Encéfalo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
9.
J Neurointerv Surg ; 7(12): 931-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25332410

RESUMO

PURPOSE: To assess hemodynamic differences between aneurysms that occlude rapidly and those occluding in delayed fashion after flow diversion in rabbits. METHODS: Thirty-six elastase-induced aneurysms in rabbits were treated with flow diverting devices. Aneurysm occlusion was assessed angiographically immediately before they were sacrificed at 1 (n=6), 2 (n=4), 4 (n=8) or 8 weeks (n=18) after treatment. The aneurysms were classified into a fast occlusion group if they were completely or near completely occluded at 4 weeks or earlier and a slow occlusion group if they remained incompletely occluded at 8 weeks. The immediate post-treatment flow conditions in aneurysms of each group were quantified using subject-specific computational fluid dynamics and statistically compared. RESULTS: Nine aneurysms were classified into the fast occlusion group and six into the slow occlusion group. Aneurysms in the fast occlusion group were on average significantly smaller (fast=0.9 cm, slow=1.393 cm, p=0.024) and had smaller ostia (fast=0.144 cm2, slow=0.365 cm2, p=0.015) than aneurysms in the slow occlusion group. They also had a lower mean post-treatment inflow rate (fast=0.047 mL/s, slow=0.155 mL/s, p=0.0239), kinetic energy (fast=0.519 erg, slow=1.283 erg, p=0.0468), and velocity (fast=0.221 cm/s, slow=0.506 cm/s, p=0.0582). However, the differences in the latter two variables were only marginally significant. CONCLUSIONS: Hemodynamic conditions after flow diversion treatment of cerebral aneurysms in rabbits are associated with the subsequent aneurysm occlusion time. Specifically, smaller inflow rate, kinetic energy, and velocity seem to promote faster occlusions, especially in smaller and small-necked aneurysms. These results are consistent with previous studies based on clinical series.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Prótese Vascular , Hemodinâmica/fisiologia , Aneurisma Intracraniano/fisiopatologia , Aneurisma Intracraniano/cirurgia , Stents , Animais , Aneurisma Intracraniano/diagnóstico por imagem , Coelhos , Radiografia
10.
J Neurosurg ; 122(1): 95-100, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25380112

RESUMO

OBJECT: Tobacco smoking is one of the most important risk factors for the formation of intracranial aneurysms and for aneurysmal subarachnoid hemorrhages. Smoking has also been suggested to contribute to the recurrence of aneurysms after endovascular coiling. To improve the understanding of the impact of smoking on long-term outcomes after coil embolization of intracranial aneurysms, the authors studied a consecutive contemporary series of patients treated at their institution. The aims of this study were to determine whether smoking is an independent risk factor for aneurysm recurrence and retreatment after endovascular coiling. METHODS: All patients who had received an intrasaccular coil embolization of an intracranial aneurysm, who had undergone a follow-up imaging exam at least 6 months later, and whose smoking history had been recorded from January 2005 through December 2012 were included in this study. Patients were stratified according to smoking status into 3 groups: 1) never a smoker, 2) current smoker (smoked at the time of treatment), and 3) former smoker (quit smoking before treatment). The 2 primary outcomes studied were aneurysm recurrence and aneurysm retreatment after treatment for endovascular aneurysms. Kruskal-Wallis and chi-square tests were used to test statistical significance of differences in the rates of aneurysm recurrence, retreatment, or of both among the 3 groups. A multivariate logistic regression analysis controlling for smoking status and for several characteristics of the aneurysm was also performed. RESULTS: In total, 384 patients with a combined total of 411 aneurysms were included in this study. The aneurysm recurrence rate was not significantly associated with smoking: both former smokers (OR 1.00, 95% CI 0.61-1.65; p = 0.99) and current smokers (OR 0.58, 95% CI 0.31-1.09; p = 0.09) had odds of recurrence that were similar to those who were never smokers. Former smokers (OR 0.78, 95% CI 0.46-1.35; p = 0.38) had odds of retreatment similar to those of never smokers, and current smokers had a lower odds of undergoing retreatment (OR 0.44, 95% CI 0.21-0.91; p = 0.03) than never smokers. Moreover, an analysis adjusting for aneurysm rupture, diameter, and initial occlusion showed that former smokers (OR 0.65, 95% CI 0.33-1.28; p = 0.21) and current smokers (OR 1.04, 95% CI 0.60-1.81; p = 0.88) had odds of aneurysm recurrence similar to those who were never smokers. Adjusting the analysis for aneurysm rupture, diameter, and occlusion showed that both former smokers (OR 0.49, 95% CI 0.23-1.05; p = 0.07) and current smokers (OR 0.82, 95% CI 0.46-1.46; p = 0.50) had odds of retreatment similar to those of patients who were never smokers. CONCLUSIONS: The results show that smoking was not an independent risk factor for aneurysm recurrence and aneurysm retreatment among patients receiving endovascular treatment for intracranial aneurysms at the authors' institution. Nonetheless, patients with intracranial aneurysms should continue to be counseled about the risks of tobacco smoking.


Assuntos
Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/cirurgia , Fumar/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Risco , Resultado do Tratamento
11.
Clin Chem ; 60(12): 1524-31, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25281703

RESUMO

BACKGROUND: Anticoagulation protocols used during mechanical circulatory support call for titration of antiplatelet agents. We compared the precision and reliability of 5 platelet function tests in healthy volunteers and donors on daily antiplatelet therapy to distinguish their efficacy for titrating antiplatelet therapy. METHODS: We assessed arachidonic acid-induced platelet function by light transmission aggregometry (LTA), Multiplate impedance aggregometry, VerifyNow, and platelet mapping by thromboelastography (TEG PM). We assessed ADP-induced platelet function by the same methods and flow cytometry. Forty healthy volunteers and 10-13 volunteers on daily aspirin and/or clopidogrel therapy were evaluated. We compared tests for intraassay precision, interassay precision (samples from 2 separate blood draws), and reliability coefficient. RESULTS: For arachidonic acid-induced platelet aggregation in healthy volunteers, intra- and interassay CVs were ≤ 10% for all methods. Intra- and interassay precision among donors on daily aspirin was ≤ 30% for all methods except LTA (38% interassay CV) and TEG PM (95% intraassay and 104% interassay CV). For ADP-induced platelet function, intra- and interassay precision was ≤ 10% and ≤ 30% for all methods. Only Multiplate demonstrated moderate or greater (R > 0.40) reliability coefficients for arachidonic acid-induced platelet function among all subjects. All methods of ADP-induced platelet function, except TEG PM, demonstrated substantial or greater (R > 0.60) reliability among all subjects. CONCLUSIONS: TEG PM is least suited to monitor effects of antiplatelet agents. Multiplate impedance aggregometry was the only method to demonstrate an acceptable reliability coefficient among healthy volunteers and donors on both aspirin and clopidogrel therapy.


Assuntos
Aspirina/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Testes de Função Plaquetária/normas , Ticlopidina/análogos & derivados , Ácido Araquidônico/farmacologia , Aspirina/administração & dosagem , Clopidogrel , Feminino , Voluntários Saudáveis , Humanos , Masculino , Inibidores da Agregação Plaquetária/administração & dosagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ticlopidina/administração & dosagem , Ticlopidina/uso terapêutico
12.
Anesth Analg ; 119(4): 891-898, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25076100

RESUMO

BACKGROUND: Statins have been shown to possess antiinflammatory and immunomodulatory effects. In this study, we sought to determine if preoperative statin therapy is associated with a reduced frequency of postoperative acute respiratory distress syndrome (ARDS) in surgical populations at increased risk of developing ARDS. METHODS: We performed a retrospective cohort evaluation of the association between preoperative statin therapy and early postoperative ARDS in patients undergoing elective high-risk thoracic and aortic vascular surgery. The association between preoperative statin therapy and postoperative ARDS was assessed using propensity-adjusted analyses to control for indication bias and confounding factors. RESULTS: Of 1845 patients, 722 were receiving preoperative statin therapy. One hundred twenty patients developed postoperative ARDS. Frequencies of ARDS among those receiving statin therapy versus those who were not was 7.2% and 6.1%, respectively (OR = 1.20; 95% CI, 0.83-1.75; P = 0.330). Neither the stratified propensity score analysis (pooled OR 0.93; 95% CI, 0.60-1.43) nor matched analysis (OR = 0.78; 95% CI, 0.48-1.27) identified a statistically significant association between preoperative statin administration and postoperative ARDS. When compared to matched controls, patients who developed postoperative ARDS did not differ in mortality (7.7% vs 8.8%, P = 0.51), hospital length of stay (21 days vs 15 days, P = 0.21), or ventilator-free days (24 days vs 25 days, P = 0.62). CONCLUSIONS: In patients undergoing high-risk surgery, preoperative statin therapy was not associated with a statistically significant reduction in postoperative ARDS. These results do not support the use of statins as prophylaxis against ARDS in patients undergoing high-risk surgery.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios/métodos , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/prevenção & controle , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Síndrome do Desconforto Respiratório/epidemiologia , Estudos Retrospectivos , Resultado do Tratamento
13.
Anesthesiology ; 120(5): 1168-81, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24755786

RESUMO

BACKGROUND: Acute respiratory distress syndrome (ARDS) remains a serious postoperative complication. Although ARDS prevention is a priority, the inability to identify patients at risk for ARDS remains a barrier to progress. The authors tested and refined the previously reported surgical lung injury prediction (SLIP) model in a multicenter cohort of at-risk surgical patients. METHODS: This is a secondary analysis of a multicenter, prospective cohort investigation evaluating high-risk patients undergoing surgery. Preoperative ARDS risk factors and risk modifiers were evaluated for inclusion in a parsimonious risk-prediction model. Multiple imputation and domain analysis were used to facilitate development of a refined model, designated SLIP-2. Area under the receiver operating characteristic curve and the Hosmer-Lemeshow goodness-of-fit test were used to assess model performance. RESULTS: Among 1,562 at-risk patients, ARDS developed in 117 (7.5%). Nine independent predictors of ARDS were identified: sepsis, high-risk aortic vascular surgery, high-risk cardiac surgery, emergency surgery, cirrhosis, admission location other than home, increased respiratory rate (20 to 29 and ≥30 breaths/min), FIO2 greater than 35%, and SpO2 less than 95%. The original SLIP score performed poorly in this heterogeneous cohort with baseline risk factors for ARDS (area under the receiver operating characteristic curve [95% CI], 0.56 [0.50 to 0.62]). In contrast, SLIP-2 score performed well (area under the receiver operating characteristic curve [95% CI], 0.84 [0.81 to 0.88]). Internal validation indicated similar discrimination, with an area under the receiver operating characteristic curve of 0.84. CONCLUSIONS: In this multicenter cohort of patients at risk for ARDS, the SLIP-2 score outperformed the original SLIP score. If validated in an independent sample, this tool may help identify surgical patients at high risk for ARDS.


Assuntos
Lesão Pulmonar Aguda/diagnóstico , Lesão Pulmonar Aguda/epidemiologia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/epidemiologia , Idoso , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco
14.
Diabetologia ; 57(7): 1446-55, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24771091

RESUMO

AIMS/HYPOTHESIS: Dysregulation of 11ß-hydroxysteroid dehydrogenase (11ß-HSD) enzyme activities are implicated in the pathogenesis of obesity and insulin resistance. The aim of the study was to determine whether hepatic 11ß-HSD type 1 (11ß-HSD-1) enzyme activity differs in people with and without obesity and type 2 diabetes. METHODS: We measured hepatic 11ß-HSD-1 activity in the overnight fasted state in 20 lean non-diabetic participants (LND), 21 overweight/obese non-diabetic participants (OND) and 20 overweight/obese participants with type 2 diabetes (ODM) using a non-invasive approach. One mg doses of [9,12,12-(2)H3]cortisol (D cortisol) and [4-(13)C]cortisone ([(13)C]cortisone) were ingested, while [1,2,6,7-(3)H]cortisol ([(3)H] cortisol) was infused intravenously to enable concurrent measurements of first-pass hepatic extraction of ingested D cortisol and hepatic conversion of ingested [(13)C]cortisone to C13 cortisol derived from the ingested cortisone (a measure of 11ß-HSD-1 activity in the liver) using an isotope dilution technique. One-way ANOVA models and Kruskal-Wallis tests were used to test the hypothesis. RESULTS: Plasma D cortisol and C13 cortisol concentrations were lower in OND than in LND (p < 0.05) over 6 h of the study. There was no difference (p = 0.15) in C13 and D cortisol concentrations between OND and ODM and between LND and ODM for the same study period. Hepatic conversion of [(13)C]cortisone to C13 cortisol was similar between groups. CONCLUSIONS/INTERPRETATION: Hepatic conversion of [(13)C]cortisone to C13 cortisol did not differ between the groups studied. We conclude that hepatic 11ß-HSD-1 activity is similar in individuals who are overweight/obese or who have type 2 diabetes.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Fígado/enzimologia , Obesidade/enzimologia , Adulto , Idoso , Índice de Massa Corporal , Feminino , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade
15.
Transfusion ; 54(8): 1997-2003; quiz 1996, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24697759

RESUMO

BACKGROUND: The use of hematopoietic progenitor cell (HPC) transplant has risen over the past two decades. A variety of adverse events (AEs) of varying severity have been noted during HPC infusions. These AEs have been associated with several factors such as the amount of dimethyl sulfoxide and white blood cells in the HPC product. We performed a single-institution retrospective analysis to determine the effect of two different HPC infusion techniques, manual push with syringes versus infusion from bags with the aid of gravity, on the occurrence of infusion-related AEs. STUDY DESIGN AND METHODS: Infusions between December 2008 and November 2010 involving peripheral blood HPCs were reviewed. Pertinent clinical and HPC product-related information was recorded. Data were analyzed to determine the incidence of infusion-related AEs and its association with patient and product-related variables. RESULTS: We found 461 AEs in 645 patients during the study period. A total of 325 (50%) experienced at least one AE. Flushing was the most common type of AE followed by nausea and hypertension. The use of syringe infusion was more commonly associated with AEs (odds ratio, 1.82 [95% confidence interval, 1.32-2.50]; p=0.002). Other independent risk factors were cryopreserved products and the amount of polymorphonuclear leukocytes in the product. CONCLUSION: To our knowledge, this is the first study examining the effect of two different infusion techniques on infusion-related AEs. Our findings suggest that the use of bags for infusion protected the patients from AEs.


Assuntos
Rubor/etiologia , Hipertensão/etiologia , Infusões Intravenosas/efeitos adversos , Náusea/etiologia , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Acetaminofen/uso terapêutico , Adolescente , Adulto , Idoso , Preservação de Sangue/instrumentação , Preservação de Sangue/métodos , Criança , Pré-Escolar , Criopreservação , Crioprotetores/efeitos adversos , Dimetil Sulfóxido/efeitos adversos , Difenidramina/uso terapêutico , Furosemida/uso terapêutico , Neoplasias Hematológicas/cirurgia , Humanos , Hidrocortisona/uso terapêutico , Lactente , Recém-Nascido , Infusões Intravenosas/métodos , Soluções Isotônicas/efeitos adversos , Pessoa de Meia-Idade , Neutrófilos/imunologia , Neutrófilos/transplante , Transplante de Células-Tronco de Sangue Periférico/métodos , Pré-Medicação , Estudos Retrospectivos , Fatores de Risco , Seringas , Adulto Jovem
16.
EJNMMI Res ; 4(1): 5, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24428856

RESUMO

BACKGROUND: In an effort to reduce necessary acquisition time to perform molecular breast imaging (MBI), we compared diagnostic performance of MBI performed with standard 10-min-per-view acquisitions and half-time 5-min-per-view acquisitions, with and without wide beam reconstruction (WBR) processing. METHODS: Eighty-two bilateral, two-view MBI studies were reviewed. Studies were performed with 300 MBq Tc-99 m sestamibi and a direct conversion molecular breast imaging (DC-MBI) system. Acquisitions were 10 min-per-view; the first half of each was extracted to create 5-min-per-view datasets, and WBR processing was applied.The 10-min-, 5-min-, and 5-min-per-view WBR studies were independently interpreted in a randomized, blinded fashion by two radiologists. Assessments of 1 to 5 were assigned; 4 and 5 were considered test positive. Background parenchymal uptake, lesion type, distribution of non-mass lesions, lesion intensity, and image quality were described. RESULTS: Considering detection of all malignant and benign lesions, 5 min-per-view MBI had lower sensitivity (mean of 70% vs. 85% (p ≤ 0.04) for two readers) and lower area under curve (AUC) (mean of 92.7 vs. 99.6, p ≤ 0.01) but had similar specificity (p = 1.0). WBR processing did not alter sensitivity, specificity, or AUC obtained at 5 min-per-view.Overall agreement in final assessment between 5-min-per-view and 10-min-per-view acquisition types was near perfect (κ = 0.82 to 0.89); however, fair to moderate agreement was observed for assessment category 3 (probably benign) (κ = 0.24 to 0.48). Of 33 malignant lesions, 6 (18%) were changed from assessment of 4 or 5 with 10-min-per-view MBI to assessment of 3 with 5-min-per-view MBI. Image quality of 5-min-per-view studies was reduced compared to 10-min-per-view studies for both readers (3.24 vs. 3.98, p < 0.0001 and 3.60 vs. 3.91, p < 0.0001). WBR processing improved image quality for one reader (3.85 vs. 3.24, p < 0.0001). CONCLUSIONS: Although similar radiologic interpretations were obtained with 10-min- and 5-min-per-view DC-MBI, resulting in substantial agreement in final assessment, notable exceptions were found: (1) perceived image quality at 5 min-per-view was lower than that for 10-min-per-view studies and (2) in a number of cases, assessment was downgraded from a recommendation of biopsy to that of short interval follow-up.

17.
Diabetes Technol Ther ; 15(9): 751-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23937615

RESUMO

BACKGROUND: Currently, patients with type 1 diabetes decide on the amount of insulin to administer based on several factors, including current plasma glucose value, expected meal input, and physical activity (PA). One future therapeutic modality for patients with type 1 diabetes is the artificial endocrine pancreas (AEP). Incorporation of PA could enhance the efficacy of AEP significantly. We compared the main technologies used for PA quantitation. SUBJECTS AND METHODS: Data were collected during inpatient studies involving healthy control subjects and type 1 diabetes. We report PA quantified from accelerometers (acceleration units [AU]) and heart rate (HR) monitors during a standardized activity protocol performed after a dinner meal at 7 p.m. from nine control subjects (four were males, 37.4±12.7 years old, body mass index of 24.8±3.8 kg/m(2), and fasting plasma glucose of 4.71±0.63 mmol/L) and eight with type 1 diabetes (six were males, 45.2±13.4 years old, body mass index of 25.1±2.9 kg/m(2), and fasting plasma glucose of 8.44±2.31 mmol/L). RESULTS: The patient-to-patient variability was considerably less when examining AU compared with HR monitors. Furthermore, the exercise bouts and rest periods were more evident from the data streams when AUs were used to quantify activity. Unlike the AU, the HR measurements provided little insight for active and rest stages, and HR data required patient-specific standardizations to discern any meaningful pattern in the data. CONCLUSIONS: Our results indicated that AU provides a reliable signal in response to PA, including low-intensity activity. Correlation of this signal with continuous glucose monitoring data would be the next step before exploring inclusion as input for AEP control.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Frequência Cardíaca/fisiologia , Monitorização Fisiológica/instrumentação , Atividade Motora/fisiologia , Aceleração , Adulto , Composição Corporal/fisiologia , Índice de Massa Corporal , Creatinina/sangue , Interpretação Estatística de Dados , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-Idade
18.
Cancer Cytopathol ; 121(12): 708-17, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23839915

RESUMO

BACKGROUND: Patients diagnosed with primary sclerosing cholangitis (PSC) and dominant strictures often undergo endoscopic retrograde cholangiopancreatography with brush cytology to exclude or confirm the development of malignancy. Equivocal (atypical or suspicious) routine cytologic results may confound patient management decisions, especially in the absence of a mass on imaging. The objective of the current study was to identify independent predictors of malignancy in patients with PSC with an equivocal cytology diagnosis. METHODS: Patients with PSC underwent brush cytology for routine cytology and fluorescence in situ hybridization (FISH) during endoscopy as per standard care. FISH slides were classified as polysomy if at least 5 cells displayed a gain of ≥ 2 probes. A retrospective search identified 102 patients without a mass lesion noted on initial imaging studies, an equivocal routine cytology, and ≥ 2 years of follow-up. RESULTS: Of 102 patients, 30 (29%) with an equivocal cytology result developed cancer within 2 years. Serum carbohydrate antigen 19-9 (CA 19-9) levels ≥ 129 U/mL (hazard ratio [HR] 3.19; P = .001) and polysomy (HR 8.70; P < .001) were each found to be predictive of cancer. Of 10 patients who had elevated CA 19-9 levels and polysomy, all went on to develop cancer (9 within 2 years). Although only 10 patients were included in this subset, the combination of elevated CA 19-9 and polysomy was found to be predictive of cancer (HR 10.92; P < .001). CONCLUSIONS: Polysomy by FISH identified those patients most likely to have or develop malignancy in the challenging clinical scenario of PSC with no mass at baseline and equivocal cytology. The combination of an elevated serum CA 19-9 level with polysomy is highly suspicious for the presence of malignancy.


Assuntos
Neoplasias dos Ductos Biliares/sangue , Neoplasias dos Ductos Biliares/patologia , Biomarcadores Tumorais/sangue , Antígeno CA-19-9/sangue , Colangite Esclerosante/sangue , Colangite Esclerosante/patologia , Lesões Pré-Cancerosas/patologia , Adulto , Idoso , Neoplasias dos Ductos Biliares/imunologia , Biópsia por Agulha , Antígeno CA-19-9/genética , Colangiopancreatografia Retrógrada Endoscópica/métodos , Colangite Esclerosante/imunologia , Estudos de Coortes , Intervalos de Confiança , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Polirribossomos , Lesões Pré-Cancerosas/sangue , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Adulto Jovem
19.
BMC Pediatr ; 12: 50, 2012 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-22583686

RESUMO

BACKGROUND: The purpose of this study was to investigate the association between Attention Deficit/Hyperactivity Disorder (ADHD) and various factors using a representative sample of US children in a comprehensive manner. This includes variables that have not been previously studied such as watching TV/playing video games, computer usage, family member's smoking, and participation in sports. METHODS: This was a cross-sectional study of 68,634 children, 5-17 years old, from the National Survey of Children's Health (NSCH, 2007-2008). We performed bivariate and multivariate logistic regression analyses with ADHD classification as the response variable and the following explanatory variables: sex, race, depression, anxiety, body mass index, healthcare coverage, family structure, socio-economic status, family members' smoking status, education, computer usage, watching television (TV)/playing video games, participation in sports, and participation in clubs/organizations. RESULTS: Approximately 10% of the sample was classified as having ADHD. We found depression, anxiety, healthcare coverage, and male sex of child to have increased odds of being diagnosed with ADHD. One of the salient features of this study was observing a significant association between ADHD and variables such as TV usage, participation in sports, two-parent family structure, and family members' smoking status. Obesity was not found to be significantly associated with ADHD, contrary to some previous studies. CONCLUSIONS: The current study uncovered several factors associated with ADHD at the national level, including some that have not been studied earlier in such a setting. However, we caution that due to the cross-sectional and observational nature of the data, a cause and effect relationship between ADHD and the associated factors can not be deduced from this study. Future research on ADHD should take into consideration these factors, preferably through a longitudinal study design.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Criança , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Estados Unidos
20.
Artigo em Inglês | MEDLINE | ID: mdl-22135489

RESUMO

PURPOSE: Geographic disparities in hospitalization rates for chronic obstructive pulmonary disease (COPD) have been observed in Texas. However, little is known about the sources of these variations. The purpose of this manuscript is to further explore the geographic disparity of COPD hospitalization rates in Texas by examining county-level factors affecting access to care. PATIENTS AND METHODS: The study is a cross-sectional analysis of the 2007 Texas Health Care Information Council, Texas, demographer population projections and the 2009 Area Resource File (ARF). The unit of analysis was county-specific hospitalization rate, calculated as the number of discharges of county residents divided by county-level population estimates. Indicators of access to care included: type of safety-net facility and number of pulmonary specialists in a county. Safety-net facilities of interest were federally qualified health centers (FQHCs) and rural health clinics (RHCs). RESULTS: There was a significant difference (P < 0.05) in hospitalization rates according to health center presence. Counties with only FQHCs had the lowest COPD hospitalization rate (132 per 100,000 observations), and counties with only RHCs had the highest hospitalization rate (229 per 100,000 observations). The presence of a pulmonary specialist was associated with a significant decrease (25%) in hospitalization rates among counties with only FQHCs. CONCLUSION: In Texas, counties with only FQHCs were associated with lower COPD hospitalization rates. The presence of a RHC alone may be insufficient to decrease hospitalizations from COPD. There are a number of factors that may contribute to these variations in hospitalization rates, such as racial/ethnic distribution, types and quality of services provided, and the level of rurality, which creates greater distances to care and lower concentration of hospitals and pulmonary specialists.


Assuntos
Centros Comunitários de Saúde/estatística & dados numéricos , Disparidades em Assistência à Saúde/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Pacientes Internados/estatística & dados numéricos , Segurança do Paciente/estatística & dados numéricos , Doença Pulmonar Obstrutiva Crônica/terapia , Características de Residência/estatística & dados numéricos , Serviços de Saúde Rural/estatística & dados numéricos , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Alta do Paciente/estatística & dados numéricos , Pneumologia/estatística & dados numéricos , Análise de Regressão , Texas , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA