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1.
《Endocrine practice》2004,10(4):311-316
ObjectiveTo evaluate whether analysis of thyroid hormones in fine-needle aspiration (FNA) of thyroid nodules can provide information about the functional status and the nature of the nodules.MethodsWe studied 4 groups of patients: group 1, 17 patients with autonomous hyperfunctioning thyroid nodules; group 2, 52 patients with cold nonfunctioning thyroid nodules; group 3, 12 patients with malignant thyroid nodules; and group 4 (control group), 10 patients with nonthyroid nodular lesions (enlarged parathyroid glands or lymph nodes). The assay of thyroid hormones was performed in FNA after the washing of needles and, with patient consent, also in normal thyroid parenchyma.ResultsThe free thyroxine (FT4) and free triiodothyronine (FT3) values were remarkably high in group 1 (mean, 5.5 ± 0.53 ng/dL and 27.6 ± 3.1 pg/mL, respectively; P < 0.05 versus group 2 and group 4, the control group). The levels of FT4 and FT3 were very low in group 3 (< 0.2 ng/dL and < 1.0 pg/mL, respectively; P < 0.05 versus group 2). Thyroglobulin values in FNA specimens were much higher than the normal range in human serum, but no significant differences were found between the various groups. The control group had low levels of FT4 and FT3 (< 0.2 ng/dL and < 1.0 pg/mL, respectively) in conjunction with low levels of thyroglobulin, whereas parathyroid hormone levels were high in parathyroid nodules.ConclusionThese results show that assay of FT4 and FT3 in FNA can yield information about the functional status of thyroid nodules and, indirectly, about the nature of nodules. In this era of sophisticated new molecular markers in FNA cytology, this low-cost diagnostic method can be readily performed in every laboratory. (Endocr Pract. 2004;10:311-316)  相似文献   

2.
PurposeEPID-based in vivo dosimetry (IVD) has been implemented for stereotactic body radiotherapy treatments of non-small cell lung cancer to check both isocenter dose and the treatment reproducibility comparing EPID portal images.Methods15 patients with lung tumors of small dimensions and treated with volumetric modulated arc therapy were enrolled for this initial experience. IVD tests supplied ratios R between in vivo reconstructed and planned isocenter doses. Moreover a γ-like analysis between daily EPID portal images and a reference one, in terms of percentage of points with γ-value smaller than 1, Pγ<1, and mean γ-values, γmean, using a local 3%–3 mm criteria, was adopted to check the treatment reproducibility. Tolerance levels of 5% for R ratio, Pγ<1 higher than 90% and γmean lower than 0.67 were adopted.ResultsA total of 160 EPID images, two images for each therapy session, were acquired during the treatment of the 15 patients. The overall mean of the R ratios was equal to 1.005 ± 0.014 (1 SD), with 96.9% of tests within ± 5%. The 2 D image γ-like analysis showed an overall γmean of 0.39 ± 0.12 with 96.1% of tests within the tolerance level, and an average Pγ<1 value equal to 96.4 ± 3.6% with 95.4% of tests with Pγ<1 > 90%. Paradigmatic discrepancies were observed in three patients: a set-up error and a patient morphological change were identified thanks to CBCT image analysis whereas the third discrepancy was not fully justified.ConclusionsThis procedure can provide improved patient safety as well as a first step to integrate IVD and CBCT dose recalculation.  相似文献   

3.
《Endocrine practice》2014,20(6):576-586
ObjectiveTo determine the association between thyroid hormone levels and sleep quality in community-dwelling men.MethodsAmong 5,994 men aged ≥ 65 years in the Osteoporotic Fractures in Men (MrOS) study, 682 had baseline thyroid function data, normal free thyroxine (FT4) (0.70 ≤ FT4 ≤ 1.85 ng/dL), actigraphy measurements, and were not using thyroid-related medications. Three categories of thyroid function were defined: subclinical hyperthyroid (thyroid-stimulating hormone [TSH] < 0.55 mIU/L), euthyroid (TSH, 0.55 to 4.78 mIU/L), and subclinical hypothyroid (TSH > 4.78 mIU/L). Objective (total hours of nighttime sleep [TST], sleep efficiency [SE], wake after sleep onset [WASO], sleep latency [SL], number of long wake episodes [LWEP]) and subjective (TST, Pittsburgh Sleep Quality Index score, Epworth Sleepiness Scale score) sleep quality parameters were measured. The association between TSH and sleep quality was examined using linear regression (continuous sleep outcomes) and log-binomial regression (categorical sleep outcomes).ResultsAmong the 682 men examined, 15 had subclinical hyperthyroidism and 38 had subclinical hypothyroidism. There was no difference in sleep quality between subclinical hypothyroid and euthyroid men. Compared to euthyroid men, subclinical hyperthyroid men had lower mean actigraphy TST (adjusted mean difference [95% confidence interval (CI)], − 27.4 [− 63.7 to 8.9] minutes), lower mean SE (− 4.5% [− 10.3% to 1.3%]), and higher mean WASO (13.5 [− 8.0 to 35.0] minutes]), whereas 41% had increased risk of actigraphy-measured TST < 6 hours (relative risk [RR], 1.41; 95% CI, 0.83 to 2.39), and 83% had increased risk of SL ≥ 60 minutes (RR, 1.83; 95% CI, 0.65 to 5.14) (all P > .05).ConclusionNeither subclinical hypothyroidism nor hyperthyroidism is significantly associated with decreased sleep quality. (Endocr Pract. 2014;20:576-586)  相似文献   

4.
BackgroundIodine is an essential trace element for the synthesis of thyroid hormones, which are keys in maternal metabolism during pregnancy as well as in neurological development during fetal and postnatal life. This was a prospective study on iodine status and thyroid function in women during pregnancy in the Basque country to assess whether there was any relationship among maternal urinary iodine, maternal thyroid function and thyrotropin (TSH) in newborns, and to explore any difference in women experiencing miscarriages.MethodsWe analyzed TSH, free T4 (FT4), free T3 (FT3), thyroid peroxidase antibody (TPO-Ab) titers in serum and urinary iodine concentrations (UIC) in 2104 women in the first trimester of pregnancy and in 1322 of them in their second trimester. We obtained neonatal TSH levels in 1868 cases.ResultsIn the first (T1) and second trimesters (T2), the median UICs were 88.5 μg/L and 140 μg/L, respectively. No relationship was found between UIC and FT4, or maternal and neonatal TSH. In T1 and T2, 9.7% and 7.5% of women were TPO-Ab positive, respectively. The total miscarriage rate was 10%. The percentage of miscarriages in healthy women was 8.9%, lower than in women with overt hypothyroidism (21.2%; p < 0.001) and than in women with subclinical hypothyroidism (15.6%; p < 0.025). The miscarriage rate was not higher in TPO-Ab-positive women.ConclusionsIn this study most women had iodine deficiency during pregnancy. Neonatal TSH is not correlated with maternal UIC during pregnancy. Pregnant women with hypothyroidism have a higher rate of miscarriages.  相似文献   

5.
BackgroundZinc status has been previously documented in cystic fibrosis (CF) infants, children and adolescents. However, despite the increasing life expectancy observed in CF populations, data regarding zinc status of CF adults are surprisingly lacking. The objectives of this study were to (1) characterize zinc status and (2) explore associations between zinc status and clinical outcomes of CF adult patients.MethodsA retrospective chart review was performed for patients who had their plasma zinc measured between 2009 and 2012. Data included demographics, clinical characteristics, biochemical parameters and co-morbid conditions.ResultsA total of 304 CF patients were included in the study. These patients displayed a good nutritional status (mean BMI ± SD: 22.7 ± 3.5) and moderate lung disease (mean FEV1 ± SD: 66.3 ± 22.2). Low plasma zinc concentration (<9.2 μmol/L) was found in 68 out of 304 CF patients (22.4%). Compared to patients with normal zinc, those with low zinc had significantly lower forced vital capacity and forced expiratory volume in one second. 72% of CF adults with low zinc suffered from bone disease (vs 49% with normal zinc, p = 0.037) and 79% had impaired glycemic status (vs 58%, p = 0.016). Accordingly, negative correlations were found between plasma zinc and glucose (r = −0.139, p = 0.0001), HbA1c (r = −0.237, p = 0.0001) and fructosamine (r = −0.134, p = 0.034). In multiple linear regression, albumin and glycemic status were significant predictors of plasma zinc.ConclusionOur data indicated that nearly one quarter of CF adults with good nutritional status and moderate lung disease had low plasma zinc concentration and that low zinc status was associated with worse clinical outcomes.  相似文献   

6.
PurposeThis study evaluated whether RapidPlan based plans (RP plans) created by a single optimization, are usable in volumetric modulated arc therapy (VMAT) for patients with prostate cancer.MethodsWe used 51 previously administered VMAT plans to train a RP model. Thirty RP plans were created by a single optimization without planner intervention during optimization. Differences between RP plans and clinical manual optimization (CMO) plans created by an experienced planner for the same patients were analyzed (Wilcoxon tests) in terms of homogeneity index (HI), conformation number (CN), D95%, and D2% to planning target volume (PTV), mean dose, V50Gy, V70Gy, V75Gy, and V78Gy to rectum and bladder, monitor unit (MU), and multi-leaf collimator (MLC) sequence complexity.ResultsRP and CMO values for PTV D95%, PTV D2%, HI, and CN were significantly similar (p < 0.05 for all). RP mean dose, V50Gy, and V70Gy to rectum were superior or comparable to CMO values; RP V75Gy and V78Gy were higher than in CMO plans (p < 0.05). RP bladder dose-volume parameter values (except V78Gy) were lower than in CMO plans (p < 0.05). MU values were RP: 730 ± 55 MU and CMO: 580 ± 37 MU (p < 0.05); and MLC sequence complexity scores were RP: 0.25 ± 0.02 and CMO: 0.35 ± 0.03 (p < 0.05).ConclusionsRP plans created by a single optimization were clinically acceptable in VMAT for patient with prostate cancer. Our simple model could reduce optimization time, independently of planner’s skill and knowledge.  相似文献   

7.
ObjectiveIn Graves' disease therapy, the amount of 131I is usually decided following two different modalities: the administration of a fixed activity or of an activity individually calculated based on a fixed value of target absorbed dose. Although the effectiveness of each of these approaches is good (about 80% of patients cured), the ALARA principle must be applied avoiding the un-justified radioactivity to the patient himself, the people living/working near him and the environment. In this paper a new approach to the 131I therapy in Graves' disease, based on the optimum value of the final thyroid mass, is presented.Design97 Graves' disease patients (29 males) were randomly assigned into three groups (GR1, GR2, GR3). In two of them (GR1, GR3) the radioiodine administering activity was calculated based on two fixed thyroid absorbed dose values (100 Gy for GR1; 400 Gy for GR3), in GR2 it was calculated based on the desired final optimum thyroid mass value mf = 0.24 m0/U0ResultsThe rate of cured patients are 48% (GR1), 97% (GR2) (z-test, p < 0.001) and 97% (GR3). The average activity administered to GR2 (393 ± 157 MBq) is lower than that administrered to GR3 patients (524 ± 201 MBq) (p = 0.007, two-tails unpaired t-test); the thyroid absorbed dose in GR2 (262 ± 78 Gy) is lower than in GR3 patients (407 ± 23 Gy) (p < 0.001, two-tails unpaired t-test).ConclusionOur results demonstrate that the thyroid-mass based approach optimizes the treatment avoiding an un-justified excess or a not-effective too low activity without time and resources consuming.  相似文献   

8.
《Endocrine practice》2007,13(5):444-450
ObjectiveTo evaluate the effect of exenatide on clinical parameters in obese patients with type 2 diabetes mellitus whose hyperglycemia is not adequately controlled despite treatment with oral hypoglycemic agents and insulin.MethodsIn this retrospective analysis, clinical progress of 52 obese patients with type 2 diabetes treated with exenatide, 5 mcg twice daily, in an outpatient setting was reviewed. Treatment initiation was between September and December 2005. Mean follow-up period was 26 weeks. Thirty-eight patients took exenatide regularly (Group A); 14 patients discontinued exenatide because of insurance, personal, or economic reasons (Group B). Measurements at baseline and at follow-up included body weight; blood pressure; and levels of hemoglobin A1c (HbA1c), high-sensitivity C-reactive protein (CRP), and plasma lipids. Insulin dosage requirements were assessed.ResultsMean body weight (± standard error of the mean) decreased by 6.46 ± 0.8 kg (P < .001) in Group A and increased by 2.4 ± 0.6 kg in Group B (P < .001). In Group A, mean HbA1c decreased by 0.6 ± 0.21% (P = .007), and the insulin dosage requirement decreased for rapid-acting and mixed insulins (P < .02). In Group A, means of the following parameters decreased: serum total cholesterol by 8.5 ± 3.3% (P = .03), triglycerides by 26 ± 7.6% (P = .01), systolic blood pressure by 9.2 ± 3.3 mm Hg (P = .02), and high-sensitivity CRP by 34 ± 14.3% (P = .05). These indices did not change in Group B.ConclusionExenatide effectively treats obese patients with type 2 diabetes on insulin, leading to weight loss and reduction in levels of HbAlc, systolic blood pressure, triglycerides, and high-sensitivity CRP. (Endocr Pract 2007;13:444-450)  相似文献   

9.
《Endocrine practice》2008,14(1):33-39
ObjectiveTo determine first-trimester thyroid function values and associations with thyroperoxidase antibody (TPO-Ab) status, smoking, emesis, and iodine-containing multivitamin use.MethodsWe collected information by interview, questionnaire, and blood draw at the initial obstetric visit in 668 pregnant women without known thyroid disease. We compared thyroid-stimulating hormone (TSH), total thyroxine (T4), and free T4 index (FT4I) values by TPO-Ab status. Multiple regression was used to identify characteristics associated with thyroid function values.ResultsThe following median (range containing 95% of the data points) thyroid function test values were obtained in 585 TPO-Ab–negative women: TSH, 1.1 mIU/L (0.04-3.6); FT4I, 2.1 (1.5-2.9); and T4, 9.9 μg/dL (7.0-14.0). The following median (range containing 95% of the data points) thyroid function test values were obtained in 83 TPO-Ab–positive women: TSH, 1.8 mIU/L (0.3-6.4) (P < .001); FT4I, 2.0 (1.4-2.7) (P = .06); and T4, 9.3 μg/dL (6.8-13.0) (P = .03) (P values denote statistically significant differences between TPO-Ab–positive and negative participants). Among TPO-Ab–negative participants, TSH level was not associated with use of iodine-containing multivitamins, smoking, or race. TSH increased 0.03 mIU/L for every year of maternal age (P = .03) and decreased by 0.3 mIU/L for every increase in parity (P < .001). T4 decreased 0.04 μg/dL for every year of maternal age (P = .04). Mean FT4I was 2.05 in smokers and 2.20 in nonsmokers (P < .01). There were no relationships between T4 or FT4I and parity, race, or iodine-containing multivitamin use.ConclusionTPO-Ab status of pregnant women should be considered when constructing trimester-specific reference ranges because elevated serum TPO-Ab levels are associated with higher TSH and lower T4 values. (Endocr Pract. 2008;14:33-39)  相似文献   

10.
《Phytomedicine》2014,21(10):1146-1153
IntroductionR(+)-pulegone is a ketone monoterpene and it is the main constituent of essential oils in several plants. Previous studies provided some evidence that R(+)-pulegone may act on isolated cardiac myocytes. In this study, we evaluated in extended detail, the pharmacological effects of R(+)-pulegone on cardiac tissue.MethodsUsing in vivo measurements of rat cardiac electrocardiogram (ECG) and patch-clamp technique in isolated myocytes we determinate the influence of R(+)-pulegone on cardiac excitability.ResultsR(+)-pulegone delayed action potential repolarization (APR) in a concentration-dependent manner (EC50 = 775.7 ± 1.48, 325.0 ± 1.30, 469.3 ± 1.91 μM at 10, 50 and 90% of APR respectively). In line with prolongation of APR R(+)-pulegone, in a concentration-dependent manner, blocked distinct potassium current components (transient outward potassium current (Ito), rapid delayed rectifier potassium current (IKr), inactivating steady state potassium current (Iss) and inward rectifier potassium current (IK1)) (EC50 = 1441 ± 1.04; 605.0 ± 1.22, 818.7 ± 1.22; 1753 ± 1.09 μM for Ito, IKr, Iss and IK1, respectively). The inhibition occurred in a fast and reversible way, without changing the steady-state activation curve, but instead shifting to the left the steady-state inactivation curve (V1/2 from −56.92 ± 0.35 to −67.52 ± 0.19 mV). In vivo infusion of 100 mg/kg R(+)-pulegone prolonged the QTc (∼40%) and PR (∼62%) interval along with reducing the heart rate by ∼26%.ConclusionTaken together, R(+)-pulegone prolongs the APR by inhibiting several cardiomyocyte K+ current components in a concentration-dependent manner. This occurs through a direct block by R(+)-pulegone of the channel pore, followed by a left shift on the steady state inactivation curve. Finally, R(+)-pulegone induced changes in some aspects of the ECG profile, which are in agreement with its effects on potassium channels of isolated cardiomyocytes.  相似文献   

11.
《Endocrine practice》2015,21(8):887-896
Objective: We studied the impact of radiofrequency ablation (RFA) on health-related quality of life (HRQL) in patients with benign thyroid nodules (TN) in a 2-year follow-up.Methods: Forty patients (35 women and 5 men; age, 54.9 ± 14.3 years) with cold thyroid solitary nodules or a dominant nodule within a normofunctioning multi-nodular goiter (volume range, 6.5 to 90.0 mL) underwent RFA of thyroid nodular tissue under ultrasound real-time assistance.Results: Data are mean and standard deviation. Energy delivered was 37,154 ± 18,092 joules, with an output power of 37.4 ± 8.8 watts. Two years after RFA, nodule volume decreased from 30.0 ± 18.2 mL to 7.9 ± 9.8 mL (-80.1 ± 16.1% of initial volume; P<.0001). Thyroid-stimulating hormone, free triiodothyronine, and free thyroxine levels remained stable. Symptom score measured on a 0- to 10-cm visual analogue scale (VAS) declined from 5.6 ± 3.1 cm to 1.9 ± 1.3 cm (P<.0001). Cosmetic score (VAS 0–10 cm) declined from 5.7 ± 3.2 cm to 1.9 ± 1.5 cm (P<.0001). Two patients became anti-thyroglobulin antibody–positive. Physical Component Summary (PCS)-12 improved from 50.4 ± 8.9 to 54.5 ± 5.3, and the Mental Component Summary (MCS)-12 improved from 36.0 ± 13.3 to 50.3 ± 6.3 (P<.0001 for both score changes).Conclusion: Our 2-year follow-up study confirms that RFA of benign TNs is effective in reducing nodular volume and compressive and cosmetic symptoms, without causing thyroid dysfunction or life-threatening complications. Our data indicate that the achievement of these secondary endpoints is associated with HRQL improvement, measured both as PCS and MCS.Abbreviations: fT3 = free triiodothyronine fT4 = free thyroxine HRQL = health-related quality of life MCS-12 = Mental Component Summary-12 PLA = percutaneous laser ablation PCS-12 = Physical Component Summary-12 RF = radiofrequency RFA = radiofrequency ablation SF-12 = Short-Form 12 Health Survey TgAb = anti-thyroglobulin antibody TN = thyroid nodule TRAb = anti-TSH-receptor antibody TSH = thyroid-stimulating hormone US = ultrasound VAS = visual analogue scale  相似文献   

12.
PurposeFDG-PET is an established tool for the diagnosis of recurrent or metastatic colorectal carcinoma. Several case series suggest that FDG-PET often detects incidental adenomatous polyps or colorectal adenocarcinomas. The aim of this study was to correlate unexpected colorectal foci of FDG uptake to pathology findings after systematic colonoscopy.Patients and methodsWe reviewed the records of 3541 patients who underwent FDG PET/CT in our institution over a 30-month period for the assessment of a known or suspected malignancy. In 85 of them, incidental, nodular shaped and well-circumscribed foci of abnormal uptake were identified in the area of the colon or rectum. Patients with segmental or diffuse abnormal colorectal uptake were excluded, as well as patients with known benign or malignant colorectal disease. Colonoscopy and complete pathology report was available in 29 patients. Maximal standardized uptake value (SUVmax) was measured in all lesions.ResultsUnexpected colorectal foci of FDG uptake were associated with colonoscopic abnormalities in 23 patients (true positive rate: 79 %). Adenocarcinomas were found in six patients (SUVmax = 7.3 ± 2.6), tubulous adenomas in four patients (SUVmax = 7.3 ± 4.9) and tubulovillous adenomas in 12 patients (SUVmax = 4.2 ± 1.1). Hyperplasic polyps with no sign of dysplasia were found in the last patient (SUVmax = 3.3). Concomitant CT abnormalities were found on PET/CT fusion in eight patients and consisted of wall thickening (n = 5) or nodular mass (n = 3). Conversely, PET was falsely positive in six patients (21 %), with no concomitant CT abnormalities and no abnormal findings at endoscopy (SUVmax = 6.2 ± 2.8, no significant difference with true positive lesions).ConclusionOur findings emphasize the need to perform a colonoscopy in front of incidental nodular colorectal foci of FDG uptake because malignant or pre-malignant neoplasms, which are not clinically apparent, are found in more than three-quarter of cases.  相似文献   

13.
《Endocrine practice》2011,17(4):541-545
ObjectiveTo determine the reliability of early radioiodine uptake (RAIU) in calculation of the radioiodine ablation dose for pediatric patients with Graves disease.MethodsThis retrospective review of medical records involved 22 pediatric patients with Graves disease, who had undergone early (4 to 8 hours) and late (24 to 26 hours) RAIU studies and were treated with iodine 131 (131I). Quantitative data are reported as mean ± standard error of the mean. Early and late RAIU and actual administered versus calculated 131I ablation doses were compared by using the paired t test. The correlation between early and late RAIU was assessed by curvilinear regression analysis. Significance was assessed at P < .05.ResultsMean early RAIU was 57.1% ± 18.2%, and mean late RAIU was 72.1% ± 14.4% (P < .05). Curvilinear regression analysis showed the following: late RAIU = 7.13 + 1.71 × (early RAIU) - 0.01 × (early RAIU)2; r2 = 0.75. The mean ablation dose of 131I based on late RAIU was 9.3 ± 2.0 mCi. The calculated radioiodine dose would have been, on average, 32% higher (12.3 ± 3.8 mCi; P < .05) had early RAIU been used.ConclusionIn children, early RAIU can be much lower than late RAIU. This may be misleading for ablation dose calculations. Therefore, late RAIU should be used to avoid overtreatment in children with Graves disease.(Endocr Pract. 2011;17:541-545)  相似文献   

14.
《Endocrine practice》2011,17(6):933-938
ObjectiveTo evaluate the glucose- and lipid-altering efficacy of colesevelam hydrochloride (HCl) when added to background metformin therapy in patients with inadequately controlled type 2 diabetes mellitus (T2DM).MethodsThis post hoc analysis included patients with T2DM from 3 randomized, double-blind, placebo- controlled pivotal studies who received metformin as part of their background antidiabetes therapy. In the pivotal studies, patients with T2DM were randomly assigned to receive colesevelam HCl (3.75 g/d) or placebo added to existing metformin (26 weeks), sulfonylurea (26 weeks), or insulin (16 weeks) monotherapy or combination therapy, wherein the combination therapies may have included metformin.ResultsIn this pooled analysis of 696 patients with T2DM who were receiving metformin monotherapy or metformin combined with other antidiabetes therapies, 355 were randomly assigned to receive colesevelam HCl and 341 to receive placebo. In comparison with placebo, colesevelam HCl significantly reduced hemoglobin A1c (A1C) and fasting plasma glucose (mean treatment difference: -0.50% and -15.7 mg/dL, respectively; P < .001 for both), as well as significantly reduced levels of low-density lipoprotein cholesterol (LDL-C; mean treatment difference: -16.5%), total cholesterol (TC; -5.8%), non-high-density lipoprotein cholesterol (non-HDL-C; -8.2%), and apolipoprotein (apo) B (-7.6%) (P < .0001 for all). Median triglyceride levels were increased with colesevelam HCl (median treatment difference: + 12.8%; P < .0001). In comparison with placebo, colesevelam HCl significantly increased apo A-I (mean treatment difference: + 3.3%; P < .0001), whereas the mean increase in HDL-C with colesevelam HCl was not significant. Colesevelam HCl therapy was generally well tolerated.ConclusionWhen added to metformin-including therapy, colesevelam HCl significantly reduced A1C and fasting glucose, as well as levels of LDL-C, TC, non- HDL-C, and apo B in patients with inadequately controlled T2DM. (Endocr Pract. 2011;17:933-938)  相似文献   

15.
PurposeThis study evaluates the radiological properties of different 3D printing materials for a range of photon energies, including kV and MV CT imaging and MV radiotherapy beams.MethodsThe CT values of a number of materials were measured on an Aquilion One CT scanner at 80 kVp, 120 kVp and a Tomotherapy Hi Art MVCT imaging beam. Attenuation of the materials in a 6 MV radiotherapy beam was investigated.ResultsPlastic filaments printed with various infill densities have CT values of −743 ± 4, −580 ± 1 and −113 ± 3 in 120 kVp CT images which approximate the CT values of low-density lung, high-density lung and soft tissue respectively. Metal-infused plastic filaments printed with a 90% infill density have CT values of 658 ± 1 and 739 ± 6 in MVCT images which approximate the attenuation of cortical bone. The effective relative electron density REDeff is used to describe the attenuation of a megavoltage treatment beam, taking into account effects relating to the atomic number and mass density of the material. Plastic filaments printed with a 90% infill density have REDeff values of 1.02 ± 0.03 and 0.94 ± 0.02 which approximate the relative electron density RED of soft tissue. Printed resins have REDeff values of 1.11 ± 0.03 and 1.09 ± 0.03 which approximate the RED of bone mineral.Conclusions3D printers can model a variety of body tissues which can be used to create phantoms useful for both imaging and dosimetric studies.  相似文献   

16.
AimsIn this study, responses of β3-adrenoceptor agonists were examined on human isolated internal anal sphincter (IAS) in order to explore their relaxant effects on hypertonicity of IAS.Main methodsThe relaxant efficacy (Emax) and potency (? logIC50) of BRL37344 and SR58611A, β3-adrenoceptor agonists, were examined in contracted IAS muscle strips. The presence of β3-adrenoceptors, and changes in intracellular calcium and cyclic nucleotide levels in IAS muscle were tested by Western blotting, epifluorescence microscopy and enzyme immunoassay, respectively.Key findingsBRL37344 and SR58611A relaxed contracted IAS muscle (Emax = 27 ± 3% and 35 ± 3%; -logIC50 = 6.26 ± 0.24 and 4.87 ± 0.13; respectively). These relaxant responses were blocked by SR59230A, a selective β3-antagonist but not by β12-selective antagonists, neuronal inhibitor or inhibition of nitric oxide synthase. The Emax of β3-agonists was similar to that of β2-selective agonists but smaller than that of isoprenaline (nonselective agonist) or β1-selective agonists. BRL37344 (100 μM) increased cAMP (1.5-fold) without cGMP change, and depressed intracellular calcium signal. β3-Adrenoceptor expression was smaller than that of β1- and β2-adrenoceptors.SignificanceThis is the first study demonstrating the presence of β3-adrenoceptor in human IAS muscle and β3-mediated relaxation of augmented sphincter tone. However, direct β3-relaxation appears smaller than that obtained for nonselective agonists which may limit their potential use in the treatment of anorectal hypertonicity disorders.  相似文献   

17.
BackgroundHF elderly patients are underrepresented in Sacubitril/Valsartan HF trials, and the effect of S/V in real-life patients with advanced age is unknown. The aim of this study was to evaluate the use and safety of S/V in a real-word cohort of elderly patients.MethodsWe performed a prospective registry of patients who started S/V in clinical practice. We compared baseline characteristics, adverse events during follow-up and causes of S/V withdrawal according to age.ResultsA total of 427 patients started treatment with S/V: 222 (52.0%) < 70 years old, 140 (32.8%) between 70 and 79 and 65 (15.2%)  80. During a mean follow-up of 7.0 ± 0.1 months S/V was well tolerated, with no age-related differences in adverse events (26.8%, 25.9%, 23.1% respectively; p = 0.83). Symptomatic hypotension tended to be more frequent in the elderly (19.8%, 25.6%, 33.3% respectively; p = 0.17). The withdrawal of S/V was more frequent in younger patients (14.4%, 10.0%, 4.6% respectively; p = 0.05) and related to poor prognosis (HR 13.51, 95% CI 3.22–56.13, p < 0.001).ConclusionsSacubitril/Valsartan is useful and safe in elderly people with HF-rEF in real-life clinical practice, and withdrawal is associated to poor prognosis. The doses achieved are lower in elderly people.  相似文献   

18.
ObjectiveDehydroepiandrosterone (DHEA) and high-density lipoprotein (HDL) are both vascular relaxants. In the circulation, HDL transports DHEA fatty acyl esters (DHEA-FAEs), which are naturally occurring lipophilic derivatives of DHEA. We studied in isolated rat mesenteric arteries whether HDL-associated DHEA-FAE improves the vasodilatory effect of HDL.Methods and resultsTo prepare DHEA-FAE-enriched HDL, we incubated DHEA with human plasma. After incubation, HDL was isolated, purified, and added in cumulative doses (0.1–125 μg/ml) to noradrenaline-precontracted rat arterial rings. DHEA-FAE-enriched HDL caused a dose-dependent relaxation (maximal 43 ± 4%), which was significantly stronger than the effect of HDL from the control incubation without addition of DHEA (25 ± 2%, p < 0.001). When plasma incubation of DHEA was carried out in the presence of lecithin:cholesterol acyltransferase (LCAT) inhibitor, the relaxation response to HDL (25 ± 3%) did not differ from the control HDL (p = 0.98). Pretreatment of the arterial rings with nitric oxide synthase (NOS) antagonist impaired the relaxation response to DHEA-FAE-enriched HDL (43 ± 4% vs. 30 ± 3%, p = 0.008). Similar experiments were performed with 17β-estradiol (E2). Compared to control HDL, E2-FAE-enriched HDL induced slightly but non-significantly stronger relaxation.ConclusionsDHEA-FAE-enriched HDL was a stronger vasodilator than native HDL, and vascular relaxation was in part mediated by NOS, suggesting that DHEA-FAE may improve HDL's antiatherogenic function.  相似文献   

19.
《Endocrine practice》2015,21(2):143-157
ObjectiveSelf-adjustment of insulin dose is commonly practiced in Western patients with type 2 diabetes but is usually not performed in Asian patients. This multinational, 24-week, randomized study compared patient-led with physician-led titration of once-daily insulin glargine in Asian patients with uncontrolled type 2 diabetes who were on 2 oral glucose-lowering agents.MethodsPatient-led (n = 275) or physician-led (n = 277) subjects followed the same dose-titration algorithm guided by self-monitored fasting blood glucose (FBG; target, 110 mg/dL [6.1 mmol/L]). The primary endpoint was change in mean glycated hemoglobin (HbA1c) at week 24 in the patient-led versus physician-led titration groups.ResultsPatient-led titration resulted in a significantly higher drop in HbA1c value at 24 weeks when compared with physician-led titration (− 1.40% vs. − 1.25%; mean difference, − 0.15; 95% confidence interval, − 0.29 to 0.00; P = .043). Mean decrease in FBG was greatest in the patient-led group (− 2.85 mmol/L vs. − 2.48 mmol/L; P = .001). The improvements in HbA1c and FBG were consistent across countries, with similar improvements in treatment satisfaction in both groups. Mean daily insulin dose was higher in the patient-led group (28.9 units vs. 22.2 units; P < .001). Target HbA1c of < 7.0% without severe hypoglycemia was achieved in 40.0% and 32.9% in the patient-led and physician-led groups, respectively (P = .086). Severe hypoglycemia was not different in the 2 groups (0.7%), with an increase in nocturnal and symptomatic hypoglycemia in the patient-led arm.ConclusionPatient-led insulin glargine titration achieved near-target blood glucose levels in Asian patients with uncontrolled type 2 diabetes who were on 2 oral glucose-lowering drugs, demonstrating that Asian patients can self-uptitrate insulin dose effectively when guided. (Endocr Pract. 2015;21:143-157)  相似文献   

20.
AimTo evaluate the performance of volumetric arc modulation with RapidArc against conventional IMRT for head and neck cancers.BackgroundRapidArc is a novel technique that has recently been made available for clinical use. Planning study was done for volumetric arc modulation with RapidArc against conventional IMRT for head and neck cancers.Materials and methodsTen patients with advanced tumors of the nasopharynx, oropharynx, and hypopharynx were selected for the planning comparison study. PTV was delineated for two different dose levels and planning was done by means of simultaneously integrated boost technique. A total dose of 70 Gy was delivered to the boost volume (PTV boost) and 57.7 Gy to the elective PTV (PTV elective) in 35 equal treatment fractions. PTV boost consisted of the gross tumor volume and lymph nodes containing visible macroscopic tumor or biopsy-proven positive lymph nodes, whereas the PTV elective consisted of elective nodal regions. Planning was done for IMRT using 9 fields and RapidArc with single arc, double arc. Beam was equally placed for IMRT plans. Single arc RapidArc plan utilizes full 360° gantry rotation and double arc consists of 2 co-planar arcs of 360° in clockwise and counter clockwise direction. Collimator was rotated from 35 to 45° to cover the entire tumor, which reduced the tongue and groove effect during gantry rotation. All plans were generated with 6 MV X-rays for CLINAC 2100 Linear Accelerator. Calculations were done in the Eclipse treatment planning system (version 8.6) using the AAA algorithm.ResultsDouble arc plans show superior dose homogeneity in PTV compared to a single arc and IMRT 9 field technique. Target coverage was almost similar in all the techniques. The sparing of spinal cord in terms of the maximum dose was better in the double arc technique by 4.5% when compared to the IMRT 9 field and single arc techniques. For healthy tissue, no significant changes were observed between the plans in terms of the mean dose and integral dose. But RapidArc plans showed a reduction in the volume of the healthy tissue irradiated at V15 Gy (5.81% for single arc and 4.69% for double arc) and V20 Gy (7.55% for single arc and 5.89% for double arc) dose levels when compared to the 9-Field IMRT technique. For brain stem, maximum dose was similar in all the techniques. The average MU (±SD) needed to deliver the dose of 200 cGy per fraction was 474 ± 80 MU and 447 ± 45 MU for double arc and single arc as against 948 ± 162 MU for the 9-Field IMRT plan. A considerable reduction in maximum dose to the mandible by 6.05% was observed with double arc plan. Double arc shows a reduction in the parotid mean dose when compared with single arc and IMRT plans.ConclusionRapidArc using double arc provided a significant sparing of OARs and healthy tissue without compromising target coverage compared to IMRT. The main disadvantage with IMRT observed was higher monitor units and longer treatment time.  相似文献   

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