Effect on Gastric Emptying and Weight Reduction of Botulinum Toxin-A Injection into the Gastric Antral Layer: An Experimental Study in the Obese Rat Model

Background: We investigated the effects of Botox-A on weight loss and gastric emptying in an experimental obese rat model. Although there is evidence of weight loss in normal-weight rats after Botox-A injection, there are no studies indicating the effect of Botox-A injection on weight loss and gastric emptying time in obese rats. Methods: 37 female Wistar Albino rats were given high calorie diet for 90 days. They were separated into 3 groups. The first group (Botox group) consisted of 15 obese rats whose gastric antrum was injected with 20 U of Botulinum Toxin Type A. The second group (Saline group) consisted of 15 obese rats whose gastric antrum was injected with 20 U of saline. The third group (Control group) had no surgical intervention. Gastric scintigraphy was performed in the 3 groups pre- and postoperatively. Results: The saline group had a weight reduction in the early postoperative days but began to gain weight thereafter. The mean weight of the Botox group between the 16th and 28th days postoperatively was significantly lower than the mean weights of the control and the saline groups (P<0.05, P<0.001). The results of gastric emptying scintigraphy in all 3 groups at day 20 revealed significantly higher T1/2 values in the Botox-A group when compared to the results of the control and saline groups (P<0.001). Conclusion: Botox-A application to the gastric antrum in obese rats leads to weight loss by increasing the gastric emptying time.     

Aseptic necrosis of the hamate: a case report.

The case of a 25-year-old man with osteonecrosis of the hamate is reported. He had pain and swelling in his right wrist. The diagnosis was accomplished with plain radiographs as well as with MRI. The case was treated surgically that included resection of the necrotic bone. The occured cavity was filled with autogenous cancellous bone graft. In addition, capito-hamate arthrodesis was performed. Histopathological examination following the operation demonstrated avascular necrosis of the hamate. The arthrodesis was obtained four months after the operation.     

Vascular Endothelial Growth Factor Expression and Cyclosporine Toxicity in Renal Allograft Rejection

The aim of this study was to evaluate the influence of vascular endothelial growth factor (VEGF) on renal function and on development of interstitial fibrosis (IF) in renal allografts. Tubular and interstitial expressions of VEGF and TNF-α, and density of macrophages in the interstitium were examined in 92 patients with nonrejected kidneys, acute rejection (AR), chronic allograft nephropathy (CAN), borderline changes (BC) and acute cyclosporin A (CsA) toxicity. Follow-up biopsy specimens from patients with AR and BC were evaluated for development of IF. A significant difference in tubular and interstitial VEGF expressions was found between patients with AR, BC, CAN and CsA toxicity (p < 0.001). Macrophage infiltration was positively correlated with VEGF and TNF-α expressions (p < 0.001). VEGF expression increased with increasing expression of TNF-α (p < 0.001). Renal function in first 6 months after initial biopsy was better in patients with marked tubular VEGF expression (p < 0.01); however, in follow-up, development of IF and graft loss was found earlier in these patients (p < 0.01 and p < 0.05, respectively). Increased renal VEGF expression has protective properties immediately following renal allograft but allows for increased risk of early IF, and therefore poor graft outcome in the long term.     

Early prediction of urinary tract infection with urinary neutrophil gelatinase associated lipocalin

Neutrophil gelatinase associated lipocalin (NGAL) is a protein identified in human neutrophil granules. The aim of the study was to assess whether urine level of NGAL (uNGAL) could represent a novel, reliable marker of urinary tract infection (UTI) and to determine the optimal cutoff level for uNGAL to predict UTI in children. Sixty patients with symptomatic UTI and 29 healthy controls were enrolled the study. Urine NGAL was measured by enzyme-linked immunosorbent assay. A dimercaptosuccinic acid (DMSA) radionuclide scan was performed within 7 days in the patients with UTI in an attempt to distinguish pyelonephritis from cystitis. Mean uNGAL level was significantly higher in the UTI group than in the controls (91.02 ng/ml vs 14.29 ng/ml, p = 0.0001) and using a cutoff 20 ng/ml for uNGAL for diagnosis of UTI, sensitivity, and specificity were 97% and 76%, respectively [area under the curve (AUC): 0.979]. Mean uNGAL/creatinine ratio (uNGAL/Cr) was also significantly higher in the UTI group [201.81 ng/mg creatinine (Cr) vs 18.08 ng/mg Cr; p = 0.0001], and using a cutoff 30 ng/mg Cr for uNGAL/Cr for diagnosis of UTI, sensitivity and specificity were 98% and 76%, respectively (AUC: 0.992). In conclusion, both uNGAL and uNGAL/Cr can be used as a novel, sensitive marker for early prediction of UTI in the absence of acute kidney injury and chronic kidney disease, and the optimal cutoff value for prediction of UTI is lower than the values determined for acute kidney injury. Further investigations with larger patient groups are required to confirm our results.     

Can we use CT pulmonary angiography as an alternative to echocardiography in determining right ventricular dysfunction and its severity in patients with acute pulmonary thromboembolism?

Purpose

Our aim was to investigate the role of computed tomography pulmonary angiography (CTPA) in the diagnosis of right ventricular dysfunction (RVD) and massive pulmonary thromboembolism (PTE).

Materials and methods

We retrospectively involved a total of 61 patients. In CTPAs, pulmonary arterial obstruction index (PAOI), right ventricular/left ventricular diameter ratio (RV/LV), and superior vena cava (SVC) diameters were calculated, followed by echocardiography (ECHO), and clinical results were evaluated based on the reports available.

Results

CTPA findings that included PAOI, RV/LV ratio, and SVC diameter were, respectively, 54.9 ± 22.7 %, 1.58 ± 0.51, and 20.3 ± 0.2 mm in patients with RVD on ECHO, whereas corresponding values were, respectively, 37.8 ± 24.2 %, 1.32 ± 0.47, and 18.4 ± 3.3 mm in those without RVD (respectively, p = 0.006, p = 0.038, and p = 0.026). PAOI was 63.3 ± 22.0 % in patients among whom massive PTE was detected and 43.1 ± 23.9 % in the group without massive PTE (p = 0.01). As for mortality; given an RV/LV ratio >1.0, this ratio had 100 % sensitivity and 35.6 % specificity, whereas given a PAOI of ≥50 %, sensitivity and specificity were 83.3 % and 57.8 %, respectively.

Conclusion

We concluded that in the patients with PTE, PAOI ≥50 % and RV/LV >1.0 in CTPA could be helpful to demonstrate RVD.     

Diagnostic value of color Doppler ultrasonography and MDCT angiography in complications of hemodialysis fistulas and grafts

Purpose

The purpose of the study was to compare the diagnostic value of color Doppler ultrasonography (CDUS) and multidetector computed tomography (MDCT) angiography against that of digital subtraction angiography (DSA) or surgery in the evaluation of failing hemodialysis arteriovenous fistulas (AVFs).

Materials and methods

CDUS and MDCT angiography were performed with 41 patients (24 men, 17 women; mean age 55.8) with dysfunctional hemodialysis fistulas. The presence of stenosis, thrombosis, aneurysm, pseudoaneurysm and seroma were recorded. The sensitivity, specificity, positive and negative predictive values (PPV and NPV) and accuracy of CDUS and MDCT angiography were calculated both individually and in combination for the detection of vascular segments with significant stenosis, thrombosis, aneurysms, pseudoaneurysms, perivascular complications and stenosis subgroups.

Results

Sixty-four segmental lesions were diagnosed by DSA or surgery. Sensitivity, specificity, PPV, NPV and accuracy of CDUS for all vascular tree lesions were 85.9%, 99.2%, 96.4%, 96.7% and 94.5%, respectively. For MDCT angiography the figures were 96.8%, 99.6%, 98.4%, 99.2% and 98.5%, respectively. When both tests were used in combination, sensitivity, specificity, PPV, NPV and accuracy for all vascular tree lesions rose to 100%.

Conclusion

Combined use of MDCT and CDUS for diagnosis of AVF dysfunctions is of equivalent value to surgery or DSA, a gold standard technique.     

Initial experience of 3 tesla apparent diffusion coefficient values in differentiating benign and malignant thyroid nodules

Purpose:

To evaluate the role of diffusion‐weighted magnetic resonance imaging (DWMRI) in differentiating benign and malignant thyroid nodules using a 3 Tesla (T) MRI scanner.

Materials and Methods:

Twenty‐eight nodules in 25 patients and 14 healthy control cases were included in the study. DWMRI was acquired with 6 b values with a 3T MRI scanner. The apparent diffusion coefficient (ADC) values of the nodules were calculated from reconstructed ADC map images and were compared with the final histopathological diagnoses.

Results:

The mean ADC value of the benign nodules was 1548 ± 353.4 (×10^?6 mm²/s), and the mean ADC of the malignant nodules was 814 ± 177.12 (×10^?6 mm²/s). The normal thyroid tissue had a mean ADC value of 1323.43 ± 210.35 × 10^?6 mm²/s (958–1689 × 10^?6 mm²/s) in the healthy control group. The ADC values were significantly different among the three groups (P = 0.001). An ADC value of 905 × 10^?6 mm²/s was determined to be the cutoff value for differentiating benign and malignant nodules, with 90% (55.5–98.3) sensitivity and 100% (81.3–100.0) specificity.

Conclusion:

This study suggests that the ADC values of nodules measured with a 3T MRI scanner could help in differentiating benign thyroid nodules from malignant nodules. J. Magn. Reson. Imaging 2013;37:1077–1082. © 2012 Wiley Periodicals, Inc.

     

Evaluation of Tc-99m(V) DMSA for imaging inflammatory lesions: An experimental study

The present study evaluated^99mTc(V) DMSA as an agent for the visualization of inflammatory lesions in comparison to^99mTc(HI) DMSA and^99mTc-HIG. All three radiopharmaceuticals were prepared with commercial kits.^99mTc(V) DMSA was prepared at neutral pH by the addition of first bicarbonate and then pertechnetate to the kit contents. The labeling efficiency was 99% as determined by ITLC. Abscesses were induced by i.m. injection of 50 μl turpentine into the right thighs of 36 Swiss albino mice. Six days later 3.7 MBq of each radiopharmaceutical was i.v. administered to 12 mice. The mice were sacrificed at 1,3,6 and 24 h later. Scintigrams were obtained with a gamma camera. The abscesses were better visualized on scintigrams with^99mTc(V) DMSA compared to^99mTc(III) DMSA, starting at 1 h. The animals were dissected and the organs were removed, weighed and the radioactivity determined with a gamma counter. The abscess to other tissue ratios were higher with^99mTc(V) DMSA than the other radiopharmaceuticals. The max. abscess/muscle ratios were 9.46 ± 3.20 (24 h), 4.19 ± 1.39 (6 h) and 5.98 ± 1.17 (24 h) and max. abscess/blood ratios were 6.22 ± 1.41, 4.09 ± 0.84 and 0.914 ± 0.351 all at 24 h for^99mTc(V) DMSA,^99mTc(III) DMSA and^99mTc-HIG, respectively. Experimental arthritis was produced in 6 New Zealand white rabbits by intra-articular injection of ovalbumin. Four days later 37 MBq of^99mTc(V) DMSA and^99mTc-HIG were each i.v. administered to 3 rabbits. Scintigrams obtained at 1, 3, 6, and 24 h clearly demonstrated arthritic joints. ROFs over arthritic joints were compared to contralateral normal joints (A/C). The max. A/C ratios were 2.10 ± 0.31 (3 h) and 2.92 ± 0.99 (24 h) for^99mTc(V) DMSA and^99mTc-HIG, respectively. Our results indicated the feasibility of imaging inflammatory lesions with^99mTc(V) DMSA.     

MR fluoroscopy-guided transthoracic fine-needle aspiration biopsy: feasibility

The purpose of this study was to evaluate the feasibility of using an open-configuration magnetic resonance (MR) imaging system with MR fluoroscopic guidance to perform percutaneous transthoracic fine-needle aspiration biopsy in patients with lung masses. Percutaneous transthoracic aspiration biopsies were performed with MR fluoroscopic guidance in 14 patients. The masses were 2-7 cm in diameter (mean, 4.1 cm). The needle was positioned by using a free-hand technique with MR fluoroscopic guidance. The needle tip reached the target lesion, and biopsy was performed. Analysis of the biopsy specimens facilitated a specific diagnosis in all patients. Pneumothorax was noted in two patients (14%) with chronic obstructive pulmonary disease. Study results showed that the described MR fluoroscopy-guided transthoracic biopsy technique can be used safely and successfully for lung masses. MR fluoroscopy can be used to reach the target lesion easily and accurately.