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1.
Renal scintigraphy is an imaging method that uses small amount of radioactive materials called radiotracers, a Gamma camera and a computer to evaluate kidney functions and its anatomy. The present work reports the comparison of the relative renal functions (RRF) calculated with technetium-99m dimercaptosuccinic acid (99mTc‑DMSA) and technetium-99m diethylenetriaminepentaacetic acid (99mTc‑DTPA) for kidney patients of ages between 5 months and 71 years. A total of 50 patients including 29 male and 21 female has been selected and studied for renography. The mean RRFs have been found to be 52.68 ± 23.63% and 47.32 ± 23.63% respectively for the left and right kidneys with 99mTc-DMSA measurement. With 99mTc-DTPA the values are 52.74 ± 23.54% and 47.26 ± 23.54% for the same. In bivariate correlation analysis, a significant positive correlation (r = 0.996, P < .001) has been found between the RRFs calculated with the two methods. Following the patients’ diagnosis, in ANOVA test, no difference has been found between the RRFs calculated for the left and right kidneys. In Bland-Altman plots, the mean difference between the two methods has been found to be 0.1 and the correlation limit lies between −4.3 and 4.2. According to the result obtained in the present work, both the 99mTc-DMSA and 99mTc-DTPA scanning methods provide almost the same RRF values. It is, therefore, always not necessary to calculate the RRFs with both the methods. This study suggests that 99mTc-DMSA may be the primary choice for the evaluation of RRF, but if the glomerular filtration rate (GFR) and renogram curve are required, 99mTc-DTPA can be the obvious selection.  相似文献   

2.
IntroductionIn preclinical research, the growing number of transgenic models has led to the need for renal-function studies in mice. Many efforts have been made to develop dedicated SPECT systems for rodents, but their availability is limited due to high capital costs. The aim of this work is to demonstrate the feasibility of mouse renal imaging by using an inexpensive alternative based on clinical gamma-cameras.MethodsA healthy mouse was scanned 3 h after injection of 6 mCi of Dimercaptosuccinic acid (DMSA) labeled with 99mTc by using a single-head gamma-camera in conjunction with a dedicated pinhole collimator. List-mode data were binned to emulate multiple injections of 1 mCi, 0.1 mCi and 0.01 mCi of 99mTc-DMSA and 6-min ventral and dorsal planar images were acquired and SPECT imaging (60 projection images acquired over 60 min) was performed. An optimization of the protocols in terms of injected activity, time scan, renal cortex uniformity and cortex-to-pelvis contrast was carried out.ResultsThe appropriate protocols were an injected activity of 0.6 mCi, combined with duration of scanning of 1 min for planar and 60 min for SPECT imaging. Our results were validated through the relative quantification of renal function, which showed that both kidneys contributed equally to the total function. They showed that functional structures of the mouse kidneys can be visually distinguished as easily as in human studies.ConclusionsOur findings showed the feasibility of conducting quantitative DMSA SPECT studies of anesthetized mice on clinical gamma cameras.  相似文献   

3.
PurposeThe aim of this proof-of-concept study is to propose a simplified personalized kidney dosimetry procedure in 177Lu peptide receptor radionuclide therapy (PRRT) for neuroendocrine tumors and metastatic prostate cancer. It relies on a single quantitative SPECT/CT acquisition and multiple radiometric measurements executed with a collimated external probe, properly directed on kidneys.MethodsWe conducted a phantom study involving external count-rate measurements in an abdominal phantom setup filled with activity concentrations of 99mTc, reproducing patient-relevant organ effective half-lives occurring in 177Lu PRRT. GATE Monte Carlo (MC) simulations of the experiment, using 99mTc and 177Lu as sources, were performed. Furthermore, we tested this method via MC on a clinical case of 177Lu-DOTATATE PRRT with SPECT/CT images at three time points (2, 20 and 70 hrs), comparing a simplified kidney dosimetry, employing a single SPECT/CT and probe measurements at three time points, with the complete MC dosimetry.ResultsThe experimentally estimated kidney half-life with background subtraction applied was compatible within 3% with the expected value. The MC simulations of the phantom study, both with 99mTc and 177Lu, confirmed a similar level of accuracy. Concerning the clinical case, the simplified dosimetric method led to a kidney dose estimation compatible with the complete MC dosimetry within 6%, 12% and 2%, using respectively the SPECT/CT at 2, 20 and 70 hrs.ConclusionsThe proposed simplified procedure provided a satisfactory accuracy and would reduce the imaging required to derive the kidney absorbed dose to a unique quantitative SPECT/CT, with consequent benefits in terms of clinic workflows and patient comfort.  相似文献   

4.
The objective of this work was to propose an automated and direct process to grade tooth wear intra-orally. Eight extracted teeth were etched with acid for different times to produce wear and scanned with an intra-oral optical scanner. Computer vision algorithms were used for alignment and comparison among models. Wear volume was estimated and visual scoring was achieved to determine reliability. Results demonstrated that it is possible to directly detect submillimeter differences in teeth surfaces with an automated method with results similar to those obtained by direct visual inspection. The investigated method proved to be reliable for comparison of measurements over time.  相似文献   

5.
为了探讨高血压患者血压与肾脏损害的关系 ,分别以RIA和ELISA共同检测尿视黄醇结合蛋白、尿微量白蛋白、尿 β2 微球蛋白和血中半胱氨酸蛋白酶抑制物C。结果显示高血压组血CystatinC、尿RBP、mALB、β2 MG均显著高于对照组 (p <0 .0 1) ,且随病程的延长而有逐渐升高的趋势。血压昼夜节律异常组的血CystatinC、尿RBP、mALB和 β2 MG也明显高于血压昼夜节律正常组 (p <0 .0 1) ,提示高血压所致的肾损害不仅与血压增高程度有关 ,而且与血压在较高水平持续时间有关。结论 :高血压病引起的肾小球、肾小管损害 ,以检测CystatinC、RBP、mALB、β2 MG可作为早期诊断肾脏损害的敏感指标  相似文献   

6.
A single nephron model, which includes the Bowman's space, Cortical interstitium, and Pelvis as well-stirred baths, is investigated. A boundary value problem, which allows for pelvic reflux, is established for the fluid-multisolute flow in the nephron. The implicit function theorem is used to establish the existence and uniqueness of a solution of the boundary value problem for the case of small permeability coefficients and transport rates.Dedicated to Professor Emertius L. P. Burton, Auburn University, for the research guidance he gave this author thirty years agoSupported in part by NIH Grant 7-ROl-DK 38817  相似文献   

7.
BackgroundThe calculation and measurement on the surface of the skin presents a significant dosimetric problem because of numerous factors which have an influence on the dose distribution in this region.AimThe overall aim of this study was to check the agreement between doses measured with thermoluminescent detectors (TLD) during tomotherapy photon beam irradiation of the skin area of a solid water cylindrical phantom with doses calculated with Hi-Art treatment planning system (TPS).Material and MethodThe measurements of the dose were made with the use of a solid water cylindrical phantom - Cheese Phantom. Two bolus phantoms were used: 5 mm and 10 mm Six different planning treatments were generated. The doses were measured using TL detectors.ResultsIn the case of a tumor located near the surface of the skin, the mean dose for 0.5 cm bolus was - 1.94 Gy, and for 1 cm bolus - 2.03 Gy. For the tumor located inside the phantom and organ at risk on the same side that TL detectors, for a 0.5 cm bolus, mean dose was 0.658 Gy, and for a 1 cm bolus, 0.62 Gy.ConclusionThe analysis of results showed that the relative percentage difference between measured and planned dose in the field of irradiation was less than 10%, while the largest differences were on the board of the field of radiation and outside of the field of irradiation, where the dose was 0.08 Gy to 1 Gy.  相似文献   

8.
We use data from an ongoing cohort study of chronic kidney patients at Salford Royal NHS Foundation Trust, Greater Manchester, United Kingdom, to investigate the influence of acute kidney injury (AKI) on the subsequent rate of change of kidney function amongst patients already diagnosed with chronic kidney disease (CKD). We use a linear mixed effects modelling framework to enable estimation of both acute and chronic effects of AKI events on kidney function. We model the fixed effects by a piece‐wise linear function with three change‐points to capture the acute changes in kidney function that characterise an AKI event, and the random effects by the sum of three components: a random intercept, a stationary stochastic process with Matérn correlation structure, and measurement error. We consider both multivariate Normal and multivariate t versions of the random effects. For either specification, we estimate model parameters by maximum likelihood and evaluate the plug‐in predictive distributions of the random effects given the data. We find that following an AKI event the average long‐term rate of decline in kidney function is almost doubled, regardless of the severity of the event. We also identify and present examples of individual patients whose kidney function trajectories diverge substantially from the population‐average.  相似文献   

9.

Aim

To evaluate the new Octavius 4D system for patient specific quality assurance and to study the correlation between plan complexity and gamma index analysis in patient specific quality assurance of VMAT using the Octavius 4D system.

Background

McNiven (2010) proposed a study to evaluate the utility of a complexity metric, the Modulation Complexity Score, to evaluate the relationship of the metric with deliverability in IMRT.

Materials and methods

Evaluation of the Octavius 4D system was carried out by gamma evaluation of user defined MLC created patterns and AAPM TG 119 benchmark plans. The relationship between plan complexity expressed as Modulation Complexity Score (MCS) and the gamma index analysis was established by a planar and volumetric gamma analysis of 106 clinically approved VMAT patient plans of different sites.

Results

Average volumetric 3D global gamma evaluation (3 mm/3%) results for the evaluation plans was 97.41% for 6 MV X-rays and 98.30% for 15 MV X-rays. Average MCS values for the head and neck, pelvic and thoracic plans were 0.2224, 0.3615 and 0.1874. Average volumetric 3D global gamma analysis (3 mm/3%) results for the head and neck, pelvic and thoracic VMAT plans were 95.45%, 97.51% and 96.98%, respectively. Out of 90 correlation analyses between the MCS and gamma passing rate, only 3 had the r value greater than 0.5.

Conclusions

The Octavius 4D system is a suitable device for patient specific pretreatment QA. Global and local gamma analysis results showed a weak correlation with the MCS.  相似文献   

10.
Since polyamines have been suggested to be one of the uremic "toxins," the levels of each polyamine, its oxidized product, acrolein, and amine oxidase in plasma of patients with renal failure were investigated. The level of putrescine was increased, whereas the level of spermine was decreased in the plasma of patients with renal failure. The patients also had increased serum amine oxidase activity leading to increased degradation of spermine. Both levels of free and protein-conjugated acrolein were also increased in plasma of patients with renal failure. The accumulated acrolein found as protein conjugates was equivalent to 180 microM, which was 6-fold higher than in plasma of normal subjects. It was found that acrolein is mainly produced by polyamine oxidase in plasma. A cell lysate containing polyamine oxidase was cytotoxic in the presence of spermine. Our results indicate that the level of acrolein is well correlated with the degree of seriousness of chronic renal failure.  相似文献   

11.
Background Regulatory T cells are important in maintaining immune homeostasis, mediating peripheral tolerance and preventing autoimmunity. Increased frequencies of CD4+CD25high T regulatory (TReg) cells have been documented in the peripheral blood of patients with several types of cancer consistent with a role in tumour escape from immunological control. We have investigated the presence of TReg cells systemically and in situ in previously untreated patients with renal cell carcinoma (RCC). Results We have shown that there is a significant increased frequency of CD4+CD25high T cells in RCC patients (n = 49) compared to normal donors (n = 38), respectively, 2.47% versus 1.50%; P < 0.0001. We confirmed these data using the FOXP3 marker of TReg cells in a subset of these patients and normal donors. The population of TReg cells identified showed the expected phenotype with CD4+CD25high population in both RCC patients and normal donors contained higher proportions of CD45RO and GITR than CD4+CD25−/low populations and exhibiting suppressive activity in an anti-CD3 and anti-CD28 induced proliferation assay. CD4+FOXP3+ T cells were detected in the tumour microenvironment by immunofluorescence and the numbers enumerated in lymphocytes recovered following enzymatic disaggregations of biopsies; their frequency was higher in the tumour than the peripheral blood of the same patients. The early follow up data show an association between higher peripheral blood regulatory T-cell count and adverse overall survival. Conclusion These data confirm the increase of TReg cells in RCC patients and provide impetus to further investigate modulation of TReg activity in RCC patients as part of therapy. Richard W. Griffiths and Eyad Elkord have equally contributed to the study.  相似文献   

12.
Background: D-serine, the enantiomer of L-serine, was identified in mammals 20?years ago. Although a close relationship between D-serine and renal dysfunction has been shown, the clinical implications of urinary D- and L-serine in humans are poorly understood. The aim of this study was to evaluate the relationship between urinary D- and L-serine with well-known renal biomarkers, and clarify the prognostic value of D- and L-serine for renal events.

Methods: This cross-sectional, prospective study included 65 patients with atherosclerotic risk factors, who were followed up for a median of 16?months. The primary endpoint was a composite of end-stage renal disease and a decline in estimated glomerular filtration rate (eGFR)?≥?25% from baseline.

Results: Urinary D-serine concentrations showed a better correlation with eGFR than did urinary L-serine, whereas neither urinary D- nor L-serine correlated with tubular markers such as urinary liver-type fatty acid-binding protein and N-acetyl-beta-D-glucosaminidase. A Cox regression analysis revealed that low urinary D-serine levels were significantly associated with the primary endpoint after adjusting for confounding factors (hazard ratio 12.60; 95% confidence interval, 3.49–45.51).

Conclusions: Urinary D-serine is associated with glomerular filtration and can be a prognostic biomarker of renal dysfunction in patients with atherosclerotic risk factors.  相似文献   


13.
Hypomagnesemia is frequent in diabetes mellitus (DM), while renal dysfunction (RD) may be associated with hypermagnesemia. Severe cardiac arrhythmias and other adverse clinical manifestations are frequent in heart failure (HF), in DM and in RD. Depletion of intracellular magnesium (icMg), which may coexist with normal serum Mg, might contribute to these deleterious effects. However, icMg content in normomagnesemic HF patients with RD or DM has not been studied. We assessed total icMg in peripheral blood mononuclear cells (PBMC) from 80 normomagnesemic furosemide-treated HF patients who were divided as follows: subgroups A (DM), B (RD), C (DM and RD), and D (free of DM or RD). PBMC from 18 healthy volunteers served as controls. IcMg content (μg/mg cell protein) in HF was lower compared to controls (1.68±0.2 vs. 2.4±0.39, p<0.001). In the entire HF group, a significant inverse correlation was evident between icMg and serum creatinine (r=−0.37) and daily furosemide dosages (r=−0.121). IcMg in the HF subgroups A, B, C, and D was 1.79±0.23, 1.57±0.23, 1.61±0.25, and 1.79±0.39, respectively (p=0.04 between A and B, p=0.08 between B and D, and non-significant in the remaining comparisons). Serum Mg, potassium, calcium, furosemide dosages and left ventricular ejection fraction were comparable in all subgroups. In conclusion, icMg depletion was demonstrable in PBMC, which may be responsible for some of the adverse clinical manifestations in HF patients. In particular, icMg depletion in RD might contribute to cardiac arrhythmias in this patient group. Mg supplementation to normomagnesemic HF patients might therefore prove beneficial.  相似文献   

14.
An optical array biosensor encapsulated with hydrolase and oxidoreductase using sol-gel immobilization technique has been fabricated for simultaneous analysis and screening of multiple samples to determine the presence of multianalytes which are clinically important in relation to renal failure. Urease and creatinine deiminase were used to detect urea and creatinine, while glucose oxidase and uricase were coimmobilized with horseradish peroxidase to quantify glucose and uric acid. Moreover, the concentrations of analytes in fetal calf serum were measured and quantified using the developed sensing system. The array biosensor showed good specificity for the simultaneous analysis of multiple samples for multianalytes without obvious cross-interference. The analytical ranges of the four analytes were between 0.01 and 10mM with detection limits of 2.5-80 microM. High precision with relative standard deviations of 3.8-9.2% (n=45) was also demonstrated. The reproducibility of array-to-array in 3 consecutive months was 5.4% (n=3). Moreover, the concentrations of analytes in fetal calf serum were 5.9 mM for urea, 0.13 mM for creatinine, 3.3mM for glucose, and 0.15 mM for uric acid, which were in good agreement with results obtained using the traditional spectroscopic methods. These results demonstrate the first use of a sol-gel-derived optical array biosensor for simultaneous analysis of multiple samples for the presence of multiple clinically important renal analytes.  相似文献   

15.
SU11248 sunitinib malate sutent® is a selective inhibitor of certain protein tyrosine kinases including VEGF-R types 1–3 PDGF-R-a and -b, c-kit, and RET. Its antitumor activity may result from both inhibition of angiogenesis and direct antiprofilerative effects on certain tumor types. In several phase I/II/III studies, sutent® was found to be effective as second and first line treatment in metastatic renal cell carcinoma (RCC). In fact, with a 37% response rate and an additional 48% stable disease sutent became the drug of choice for first line treatment in RCC. Sutent® was also effective as second line treatment in patients with gastrointestinal stromal tumors (GIST) with 8% response rate, 70% stable disease and a 20-month median survival. Prolonged stable disease was also documented in neuroendocrine tumors. In addition, a phase II study in multitreated women with breast cancer, sutent® demonstrated a moderate activity with 16% clinical benefit. Finally, in non-small cell lung cancer (NSCLC) in patients’ progressing on chemotherapy sutent® was able to achieve a 10% response rate, a level of activity similar to those documented by other agents approved for lung cancer. The agent is being tested in other tumors with a modified schedule of dosage.  相似文献   

16.
杨霞  陈世德 《蛇志》2010,22(4):345-346
目的观察眼镜蛇咬伤患者早期肝、肾功能及心肌酶的改变,以探讨其临床意义。方法对30例眼镜蛇咬伤患者入院时即抽取静脉血2.0 ml,分离血清,按常规方法行肝、肾功能及心肌酶的测定,并与健康体检者进行比较。结果与对照组比较,眼镜蛇咬伤患者早期肝功能及心肌酶指标显著升高(P0.05);肾功能检测结果差异无显著性(P0.05)。结论通过对眼镜蛇咬伤患者肝、肾功能及心肌酶的测定,了解患者肝脏、肾脏、心肌损害程度,对指导临床治疗具有一定意义。  相似文献   

17.
Purpose Although various types of immunotherapy have been used to improve the prognosis of patients with advanced renal cell carcinoma (RCC), adoptive immunotherapy using gamma-delta (γδ) T cells has not yet been tried. In this study, we designed a pilot study of adoptive immunotherapy using in vitro activated γδ T cells against advanced RCC to evaluate the safety profile and possible anti-tumor effects of this study. Experimental design Patients with advanced RCC after radical nephrectomy were administered via intravenous infusion in vitro-activated autologous γδ T cells every week or every 2 weeks, 6–12 times, with 70 JRU of teceleukin. Adverse events, anti-tumor effects and immunomonitoring were assessed. The anti-tumor effects were evaluated according to tumor doubling time (DT) by computed tomography (CT) and immunomonitoring was performed by flow cytometric analysis. Results Seven advanced RCC patients were entered in this study. The most common adverse events were fever, general fatigue and elevation of hepatobiliary enzymes, but no severe adverse events were seen. Prolongation of tumor DT was seen in three out of five patients; these three patients showed an increase in the number of γδ T cells in peripheral blood and also a high response to the antigen in vitro. Conclusions The results indicated that adoptive immunotherapy using in vitro-activated autologous γδ T cells was well tolerated and induced anti-tumor effects.  相似文献   

18.
BackgroundEstimation of nutritional requirements is a difficult task, especially for nutrients whose requirements have skewed distribution like iron in menstruating women.ObjectiveTo mathematically develop a simplified population data analysis using gamma distribution for the estimation of nutritional requirements, not depending on extensive numerical calculation.MethodsThe required equations for the estimation of requirements were devised and solved. Existing data of iron intakes and iron losses in literature were fitted to cumulative distribution curves including gamma distribution. The proposed method was applied to the estimation of iron requirements in women using the National Health and Nutrition Survey data from 2003 to 2007 in Japan.ResultsThe type 2 equation of nutritional state is first introduced: prevalence of inadequate nutritional state = Σ(individuals with intake/requirement <1)/(total number of individuals). The prevalence of inadequate nutritional status is determined by F-distribution with positive real number parameters, if the intake and the requirement have independent gamma distributions. The sum of basal and menstrual iron losses is well approximated by gamma distribution, if the basal and menstrual iron losses have independent gamma distributions. Using these relationships, an approximate estimate of iron requirements was determined. Iron intakes and losses were found to be well approximated by gamma distribution. The median of the coefficient of variation (CV) of basal iron loss was 34 %. A new correction method for intra-individual variation in gamma distribution under constant CV is presented also. The median of the estimated median iron requirement was 8.12 mg, 8.15 mg and 8.18 mg for women aged 18−29 years, respectively, as the exact numerical estimate, the approximate estimate using BETA.INV in Excel and the approximate estimate using F.INV in Excel. For women aged 30−49 years, it was 9.15 mg, 9.17 mg and 9.14 mg. The intake covering the needs of 97.7 % women was 14.55 mg, 14.44 mg and 14.49 mg for women aged 18−29 years, and 15.70 mg, 15.77 mg and 15.60 mg for women aged 30−49 years.ConclusionThe approximate estimates of iron requirements agreed well with the exact numerical estimate. The proposed method is useful for the estimation of iron requirements in menstruating women that usually requires extensive numerical calculations.  相似文献   

19.
Using Escherichia coli as a model bacterium, we tested a photon-counting method for enumeration of bacteria. This method is based on the principle that microscopic sized luminous particles in a wide field can be directly detected and counted using a photon-counting TV camera without the use of a microscope. E. coli cells were labeled with peroxidase and luminescence induced by adding a luminol-based reaction mixture. The number of luminous spots in the TV images was in good agreement with the number of bacterial colonies grown from labeled cells. The results show that our method provides a rapid and easy microbial counting system for such purposes as clinical diagnosis, microbial analysis in food, and environmental assessment.  相似文献   

20.
PurposeNutritional status and micronutrient levels of end stage renal disease (ESRD) patients may vary depending on the mode of renal replacement therapy (RRT). We aimed to compare the effects of hemodialysis, peritoneal dialysis (PD) and renal transplantation (RT) on micronutrient levels and nutritional status in ESRD patients.Patients and MethodsA total of 77 ESRD patients who had not received RRT were included in this prospective longitudinal study. All ESRD patients underwent a blood serum analysis that assessed the micronutrients such as selenium, copper, zinc, chromium, retinol, thiamine and vitamin B6 as well as a nutritional status assessment. After the baseline assessments and the initiation of RRT was accomplished, all patients were followed for 6 months.ResultsThe study showed significant improvements in subjective global assessment scores (percentage increases in score A were 26.6 and 36.6; p = 0.039 and p = 0.001; respectively), mid-arm circumference and the skin-fold thicknesses (p < 0.001, p < 0.001; respectively) in the RT and hemodialysis groups. The examinations at sixth month revealed a significant increase in body weight (4.8 kg; p = 0.002) and albumin levels (0.6 g/dL; p < 0.001) in only RT group. Zinc, thiamin and vitamin B6 were the most deficient micronutrients (44.1 %, 24.7 % and 35.1 %; respectively) in ESRD patients. There was a significant increase in selenium and retinol levels (p = 0.020 and p < 0.001; respectively) but a significant decrease in thiamin levels (p = 0.041) in RT patients. A significant increase in retinol levels (p = 0.028) and a significant decrease in thiamin levels (p = 0.022) was observed in the hemodialysis patients. However, no significant change in micronutrient levels was observed in the PD patients.ConclusionThe results support the recommendation that ESRD patients should be supplemented with water-soluble vitamins, especially thiamine and vitamin B6, and trace elements, especially zinc. RT appears to be superior to other modes of RRT when examining SGA score, anthropometric measurements, albumin and micronutrient levels.  相似文献   

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