Diagnostic value of [ 68 Ga]Ga-Pentixafor PET/CT in malignant melanoma: a pilot study

OBJECTIVE

To evaluate the diagnostic value of [ 68 Ga] Ga-Pentixafor in malignant melanoma patients.

METHODS

In this prospective study, patients with histology-proven melanoma were included and underwent [ 18 F]fluoro-D-glucose ([ 18 F]FDG) and [ 68 Ga] Ga-Pentixafor PET/computed tomography (CT) within a week. Suspicious lesions were interpreted as benign vs. malignant, and the corresponding semi-quantitative PET/CT parameters were recorded and compared.

RESULTS

Twelve consecutive melanoma patients (mean age: 60 ± 6) were included. Two patients were referred for initial staging, two for detecting recurrence and eight for evaluating the extent of metastases. Overall, [ 18 F]FDG PET/CT showed 236 tumoral lesions, including two primary tumors, two recurrent lesions, 29 locoregional metastases and 203 distant metastases. In [ 68 Ga]Ga-Pentixafor PET/CT, 101 tumoral lesions were detected, including two primary tumors, one recurrence, 16 locoregional metastases and 82 distant metastases. Notably, a documented brain metastasis was only visualized on [ 68 Ga]Ga-Pentixafor PET/CT images. Compared with [ 18 F]FDG, [ 68 Ga]Ga-Pentixafor PET/CT provided a 42% detection rate. Regarding semi-quantitative measures, the intensity of uptake and tumor-to-background ratios were significantly lower on [ 68 Ga]Ga-Pentixafor PET/CT [average maximum standard uptake value (SUV max ) of 2.72 ± 1.33 vs. 11.41 ± 14.79; P value <0.001 and 1.17 ± 0.53 vs. 5.32 ± 7.34; P value <0.001, respectively].

CONCLUSION

When comparing [ 68 Ga]Ga-Pentixafor PET/CT with [ 18 F]FDG PET/CT, not only did [ 68 Ga]Ga-Pentixafor PET/CT detect fewer lesions, but the intensity of uptake and the TBRs were also lower on [ 68 Ga]Ga-Pentixafor PET/CT. Thus, our results may indicate a limited potential of this novel tracer in cutaneous melanoma patients compared to [ 18 F]FDG PET/CT. Given the lower TBRs, applying this radiotracer in radioligand therapies is also questionable.

The FEDBD plasma's quantitative investigation of skin parameters: Skin elasticity, thickness, density, tissue oxygenation, perfusion, and edema

This study used the FEDBD plasma device for skin rejuvenation in animal samples. There were two groups of six male Wistar rats. Before starting the treatment, immediately after the treatment, the fourth week, and the tenth week of follow-up, biometric tests were performed, including moisture level, evaporation from the skin surface, erythema and melanin, skin elasticity and firmness with an MPA9 device and cutometer. The thickness and density of the epidermis and dermis, an essential indicator in rejuvenation, were evaluated with a skin ultrasound device. Also, the level of oxygen, perfusion, and interstitial water (edema) was checked using a Tivita tissue hyperspectral camera at a depth of 6 mm of the skin.

Electrostatic interactions of enzymes in non-aqueous conditions: insights from molecular dynamics simulations

Electrostatic interactions of enzymes and their effects on enzyme activity and stability are poorly understood in non-aqueous conditions. Here, we investigate the contribution of the electrostatic interactions on the stability and activity of enzymes in the non-aqueous environment using molecular dynamics simulations. Lipase was selected as active and lysozyme as inactive model enzymes in non-aqueous media. Hexane was used as a common non-aqueous solvent model. In agreement with the previous experiments, simulations show that lysozyme has more structural instabilities than lipase in hexane. The number of hydrogen bonds and salt bridges of both enzymes is dramatically increased in hexane. In contrast to the other opinions, we show that the increase of the electrostatic interactions in non-aqueous media is not so favorable for enzymatic function and stability. In this condition, the newly formed hydrogen bonds and salt bridges can partially denature the local structure of the enzymes. For lysozyme, the changes in electrostatic interactions occur in all domains including the active site cleft, which leads to enzyme inactivation and destabilization. Interestingly, most of the changes in electrostatic interactions of lipase occur far from the active site regions. Therefore, the active site entrance regions remain functional in hexane. The results of this study reveal how the changes in electrostatic interactions can affect enzyme stability and activity in non-aqueous conditions. Moreover, we show for the first time how some enzymes, such as lipase, remain active in a non-aqueous environment.Communicated by Ramaswamy H. Sarma.

Supercritical CO2/Deep Eutectic Solvent Biphasic System as a New Green and Sustainable Solvent System for Different Applications: Insights from Molecular Dynamics Simulations

Deep eutectic solvents (DESs) are one of the most interesting research subjects in green chemistry nowadays. Due to their low toxicity, simple synthesis, and lower prices, they have gradually taken the place of other green solvents such as ionic liquids (ILs) in sustainable processes. However, problems such as high viscosity and high polarity limit the applications of DESs in areas such as extraction, catalysis, and biocatalysis. In this work, we introduce and evaluate the potential application of scCO2/DES for the first time. Molecular dynamics simulations were used to examine the phase behavior, polarity, molecular mobilities, and microstructure of this system. Results show that CO2 molecules can significantly diffuse to the DES phase, while DES components do not appear in the scCO2 phase. The diffused CO2 molecules significantly enhanced the molecular mobility of the DES components. The presence of CO2 molecules changes the DES polarity so that hexane can be solubilized and dispersed in the DES phase. Radial distribution functions show that the solubilized CO2 molecules have negligible effects on the microstructure of DES. It was shown that chloride and urea are the main interaction sites of CO2 in DES. The results of this study show that scCO2/DES as a new class of green and versatile solvents can open a new promising window for research in sustainable chemistry and engineering.

A novel AI-based approach for modelling the fate, transportation and prediction of chromium in rivers and agricultural crops: A case study in Iran

Chromium (Cr) pollution caused by the discharge of industrial wastewater into rivers poses a significant threat to the environment, aquatic and human life, as well as agricultural crops irrigated by these rivers. This paper employs artificial intelligence (AI) to introduce a new framework for modeling the fate, transport, and estimation of Cr from its point of discharge into the river until it is absorbed by agricultural products. The framework is demonstrated through its application to the case study River, which serves as the primary water resource for tomato production irrigation in Mashhad city, Iran. Measurements of Cr concentration are taken at three different river depths and in tomato leaves from agricultural lands irrigated by the river, allowing for the identification of bioaccumulation effects. By employing boundary conditions and smart algorithms, various aspects of control systems are evaluated. The concentration of Cr in crops exhibits an accumulative trend, reaching up to 1.29 µg/g by the time of harvest. Using data collected from the case study and exploring different scenarios, AI models are developed to estimate the Cr concentration in tomato leaves. The tested AI models include linear regression (LR), neural network (NN) classifier, and NN regressor, yielding goodness-of-fit values (R2) of 0.931, 0.874, and 0.946, respectively. These results indicate that the NN regressor is the most accurate model, followed by the LR, for estimating Cr levels in tomato leaves.

Diagnostic value of [ 68 Ga]Ga-Pentixafor versus [ 18 F]FDG PET/CTs in non-small cell lung cancer: a head-to-head comparative study

OBJECTIVE

In this study, we aimed to compare the diagnostic value of [ 68 Ga]Ga-Pentixafor and [ 18 F]FDG PET/CT in the evaluation of non-small cell lung cancer (NSCLC) patients.

METHODS

Patients with pathology-proven NSCLC were prospectively included. Patients underwent [ 18 F]FDG and [ 68 Ga]Ga-Pentixafor PET/CT within 1 week. All suspicious lesions were interpreted as benign or malignant, and the corresponding PET/CT semi-quantitative parameters were recorded. A two-sided P -value <0.05 was considered significant.

RESULTS

Twelve consecutive NSCLC patients (mean age: 60 ± 7) were included. All patients underwent both [ 18 F]FDG and [ 68 Ga]Ga-Pentixafor PET/CT scans with a median interval of 2 days. Overall, 73 abnormal lesions were detected, from which 58 (79%) were concordant between [ 18 F]FDG and [ 68 Ga]Ga-Pentixafor PET/CT. All primary tumors were clearly detectable in both scans visually. Also, [ 68 Ga]Ga-Pentixafor PET/CT demonstrated rather comparable results with [ 18 F]FDG PET/CT scan in detecting metastatic lesions. However, malignant lesions demonstrated significantly higher SUVmax and SUVmean in [ 18 F]FDG PET/CT ( P -values <0.05). Regarding the advantages, [ 68 Ga]Ga-Pentixafor depicted two brain metastases that were missed by [ 18 F]FDG PET/CT. Also, a highly suspicious lesion for recurrence on [ 18 F]FDG PET/CT scan was correctly classified as benign by subsequent [ 68 Ga]Ga-Pentixafor PET/CT.

CONCLUSION

[ 68 Ga]Ga-Pentixafor PET/CT was concordant with [ 18 F]FDG PET/CT in detecting primary NSCLC tumors and could visualize the majority of metastatic lesions. Moreover, this modality was found to be potentially helpful in excluding tumoural lesions when the [ 18 F]FDG PET/CT was equivocal, as well as in detecting brain metastasis where [ 18 F]FDG PET/CT suffers from poor sensitivity. However, the count statistics were significantly lower.

The quantitative investigation of spark plasma on skin parameters with skin elasticity, thickness, density, and biometric characteristics

Cold atmospheric plasma has been developed and utilized as a novel technique for skin rejuvenation because of its various effects on cells and living things. This study investigated the accuracy of this claim and any possible side effects of using spark plasma to rejuvenate skin. The present work is the first quantitative investigation using animal models. 12 Wistar rats were divided into two groups for this investigation. To compare the skin's natural process with the treated skin, the first group underwent a single session of plasma therapy, while the second group served as the control group. The back of the necks of the samples was shaved for 20 cm. Before beginning treatment, the MPA9 multifunctional skin tester was used to determine the melanin index, erythema index, and transepidermal water loss (TEWL). The skin's thickness and density were assessed using sonography, and its elasticity index was calculated using a Cutometer. The samples were exposed to plasma radiation in the designated area (in a triangular pattern). The abovementioned signs were examined immediately after the following therapy and at the weekly appointment 2-4 weeks later. Optical spectroscopy was also used to demonstrate the presence of active species. In this study, we found that a plasma spark therapy session significantly boosts skin elasticity, and the ultrasound results revealed a significantly increased skin thickness and density. The plasma increased the amount of skin surface evaporation, erythema, and melanin immediately following the treatment. However, 4 weeks later, it recovered to its former state and did not differ significantly from before the therapy.

Novel Graphene oxide-Polyethylene Glycol mono-4-nonylphenyl Ether adsorbent for solid phase extraction of Pb2+ in blood and water samples

A novel and efficient Graphene Oxide-Polyethylene Glycol mono-4-nonylphenyl Ether (GO-PEGPE) nanocomposite was synthesized and used for solid phase extraction of trace levels of Pb²⁺ in different water and blood samples. The synthesized adsorbent was then characterized by the Fourier Transform-Infrared spectrophotometry (FT-IR), Field Emission-Scanning Electron Microscopy (FE-SEM), Energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction analysis (XRD). To optimize the critical parameters including pH of samples solution, amounts of adsorbent and extraction time, the response surface methodology based on the central composite design (RSM-CCD) was used and based on the results, pH = 6.0, extraction time = 22 min and amounts of adsorbent = 15 mg were selected as the optimum conditions. The relative standard deviation based on seven replicate analysis of 2 µg L^-1 Pb²⁺ was 5.2% and the limit of detection was 0.023 µg L^-1 (n = 8). The results of adsorption isotherm investigation show that the adsorption of Pb²⁺ onto the GO-PEGPE nanocomposite obeyed by the Langmuir isotherm with the maximum adsorption capacity of 69.44 mg g^-1. Also, based on the Temkin and Dubinin-Radushkevich (DR) isotherms, the adsorption of Pb²⁺ onto the GO-PEGPE nanocomposite is a physisorption phenomenon and the consequences of the kinetic models illustrated that the adsorption of Pb²⁺ followed by the pseudo second order adsorption kinetic model. Finally, the proposed method was successfully applied for preconcentration of Pb²⁺ in different water and blood samples of turning industry workers.

Synthesis of a polyaminocarboxylate-based aluminum complex and its structural studies using 1H{13C}-HMBC NMR and a Karplus-type function

The HBED chelator is used to stabilize small and hard metal ions such as Fe³⁺, Ti⁴⁺, Ga³⁺ and Al³⁺ in both medicine and industry. While the coordination of hexadentate HBED^4- is known in the case of Fe³⁺, Ti⁴⁺ and Ga³⁺, it is unknown in the case of the small Al³⁺ ion since its corresponding complex has never been fully characterized. Thus, in this work the coordination pattern in a newly synthesized aluminum HBED-based complex ([Al-HBED-NN]^-Na⁺) was determined using 2D NMR in conjunction with DFT calculations.

68Ga-DOTATATE Uptake in an Intraosseous Hemangioma, as a Potential Cause of False-Positive PET/CT Finding, Simulating Tumoral Involvement

ABSTRACT

We present the case of a 32-year-old man with a history of hypophosphatemia and multiple bone fractures, being evaluated at our center for a potential mesenchymal tumor. 68Ga-DOTATATE PET/CT revealed a highly 68Ga-DOTATATE-avid lesion in the ethmoidal sinus extending to the nasal cavity. Following resection, histologic examination of the specimen confirmed the diagnosis of "intraosseous hemangioma," a potential cause of false-positive finding of 68Ga-DOTATATE PET/CT imaging in patients being evaluated for occult malignancies, especially at the traumatic/fractured sites.

Non-Cutaneous Melanoma, Findings and Prognostic Value of FDG PET/CT: A Case Series of 23 patients and review of the literature

Objectives

Non-cutaneous malignant melanomas (NCM) are rare malignancies. Due to their nonspecific symptoms, they present later in life. The value of FDG PET/CT in this group of patients is not clear. The aim of this study is to assess the role of FDG PET/CT in the management of NCM and its prognostic implication.

Methods

We retrospectively selected twenty-three patients with a diagnosis of NCM evaluated with FDG PET/CT in Shariati hospital between 2019 and 2021. The PET/CT data were reviewed and compared with available conventional imaging findings. Five patients died within five months. The surviving patients were followed within a time interval of 7 to 27.5 months after their PET/CT study, regarding their disease status.

Results

Among 23 patients (8 ocular, 5 sinonasal, 3 pharyngeal, 2 anorectal, 2 vulvovaginal, and 3 unknown primaries), PET/CT was able to detect residual primary disease, assess treatment response, and reveal or exclude metastases. Additional lesions compared to conventional imaging were found in five, while in one with brain metastases PET/CT was unable to detect lesions on MRI. Thirteen patients had negative PET/CT finding of which 11 (85%) did not have remarkable finding on follow-up. Metastatic disease was recognized in eight. Patients with extensive metastases on FDG PET/CT had a poorer outcome.

Conclusion

Similar to cutaneous melanoma, PET/CT is valuable in the management of NCM patients and is superior to conventional imaging modalities, with the exception of brain metastases. Patients with negative PET/CT findings have a better outcome as opposed to patients with significant positive PET/CT findings.

A hybrid computational intelligence approach for bioremediation of amoxicillin based on fungus activities from soil resources and aflatoxin B1 controls

Nowadays, releasing the Emerging Pollutants (EPs) in the nature is one of the main reasons for many health and environmental disasters. Amoxicillin as an antibiotic is one of the EPs and categorized as the Endocrine Disrupting Compounds (EDCs) in hazardous materials. Accumulation of amoxicillin in the soil bulk increases the cancer risk, drug resistances and other epidemiological diseases. Hence, the soil bioremediation of antibiotics can be a solution for this problem which is more environmental-friendly system. This study technically creates a bio-engine setup in soil bulk for remediation of amoxicillin based on Aspergillus Flavus (AF) activities and Removal Percentage (RP) of amoxicillin with Aflatoxin B1 Generation (AG) controls. The main novelty is to propose a hybrid computational intelligence approach to do optimization for mechanical and biological aspects and to predict the behavior of bio-engine's effective mechanical and biological features in an intelligent way. The optimization model is formulated by the Central Composite Design (CCD) which is set by the Response Surface Methodology (RSM). The prediction model is formulated by the Random Forest (RF), Adaptive Neuro Fuzzy Inference System (ANFIS) and Random Tree (RT) algorithms. According to the experimental practices from real soil samples in different times and places, concentration of amoxicillin and Aflatoxin B1 are set equal to 25 mg/L (ppm) and 15 μg/L (ppb). Likewise, the outcomes of experiments in CCD-RSM computations are evaluated by curve fitting comparisons between linear, 2FI, quadratic and cubic polynomial equations with considering to regression coefficient and predicted regression coefficient values, ANOVA and optimization by sequential differentiation. Based on the results of CCD-RSM, the RP performance in the optimum conditions is measured around 86% and in 25 days after runtime, the RP and AG are balanced in the safe mode. The proposed hybrid model achieves the 0.99 accuracy. The applicability of the research is done using real field evaluations from drug industrial park in Mashhad city in Iran. Finally, a broad analysis is done and managerial insights are concluded. The main findings of the present research are: (I) with application of bioremediation from fungus activities, amoxicillin amounts can be control in soil resources with minimum AG, (II) ANFIS model has the best accuracy for smart monitoring of amoxicillin bioremediation in soil environments and (III) based on the statistical assessments Aeration Intensity and AF/Biological Waste ratio are most effective on the amoxicillin removal percentage.

Effect of Diet on Physiologic Bowel 18F-FDG Uptake

Intestinal ¹⁸F-FDG uptake is variable in whole-body PET/CT. In cancer patients, particularly those suspected of relapse or metastasis, ¹⁸F-FDG absorption might interfere with scan interpretation. This study evaluated the effect of diet on intestinal ¹⁸F-FDG absorption. Methods: In total, 214 patients referring for oncologic ¹⁸F-FDG PET/CT participated. They were randomly divided into 2 groups and asked to follow either a routine diet (RD) or a low-carbohydrate, high-fat diet (LCHFD) for 24 h before the study. The small bowel and different parts of the colon (the cecum; the ascending, transverse, and descending segments; and the hepatic and splenic flexures) were evaluated and visually interpreted by nuclear medicine experts. Bowel uptake was graded through comparison with that in the liver as absent, mild, moderate, or severe. Results: Significantly higher ¹⁸F-FDG uptake in the descending colon (P = 0.001) and small intestine (P = 0.01) was observed in the RD group than in the LCHFD group. After patients with bowel cancer were omitted from the statistical analysis, no significant differences in the final results were seen. Conclusion: An LCHFD for 24 h before ¹⁸F-FDG PET imaging resulted in lower ¹⁸F-FDG uptake in the descending colon and small bowel than did an RD, assisting the interpreting physician by reducing the intestinal activity interference for more accurate diagnostic interpretation.

FDG PET/CT of an Advanced Case of Malignant Nerve Sheath Tumor of Pleura

ABSTRACT

We present a rare case of malignant nerve sheath tumor of pleura referred for the evaluation of metastases and local invasion. FDG PET/CT demonstrated a hypermetabolic tumoral lesion extensively involving the right pleura with no involvement of mediastinal structures or pulmonary parenchyma and no clear evidence of distant metastasis. Malignant nerve sheath tumor of pleura is an extremely rare entity, and FDG PET/CT is valuable in demonstrating the extent of disease and can have potential role for postsurgical as well as postchemotherapy assessment of possible residual disease.

99mTc-PSMA SPECT/CT Versus 68Ga-PSMA PET/CT in the Evaluation of Metastatic Prostate Cancer

BACKGROUND

99mTc-prostate-specific membrane antigen (PSMA) SPECT/CT is less expensive and readily available modality compared with 68Ga-PSMA PET/CT for imaging prostate cancer (PC). The aim of this study is to compare the value of these 2 modalities in patients confirmed or suspicious to have metastatic prostate cancer.

PATIENTS AND METHODS

Twenty-two patients with the mean age of 66.6 ± 10.1 years were studied using 99mTc-PSMA SPECT/CT and 68Ga-PSMA PET/CT, with less than 7 days interval between the 2 imaging procedures. Whole-body PET/CT was done 60 minutes after IV injection of 185 MBq (5 mCi) of 68Ga-PSMA. 99mTc-PSMA SPECT/CT was performed 3 hours after IV injection of 555 to 740 MBq (15-20 mCi) of 99mTc-PSMA. The images of each modality were interpreted independently, and the results were compared according to patient-based as well as region-based analyses.

RESULTS

In patient-based evaluation, both 99mTc-PSMA SPECT/CT and 68Ga-PSMA PET/CT scans were positive in 95.45% (21/22). In region-based evaluation, 68Ga-PSMA PET/CT detected 53 regions (median of 2 regions per patient; range, 0-5), whereas 43 (median of 2 regions per patient; range, 0-5) were detected by 99mTc-PSMA SPECT/CT. Most of these differences could be explained by lower detection rate of 99mTc-PSMA SPECT/CT in prostate bed (n = 6). PET/CT detected more involved regions than SPECT/CT (P = 0.007), whereas similar frequency of extraprostatic lesions were diagnosed in both modalities (P = 0.102). Significant correlation was also demonstrated between serum prostate-specific antigen level and imaging parameters of disease extension detected by 2 modalities.

CONCLUSIONS

99mTc-PSMA SPECT/CT could be a potential substitute for 68Ga-PSMA PET/CT in high-risk patients, except when evaluation of prostate bed is of major concern.

Potential role of 18F-FDG PET/CT in a case of progressive Rosai Dorfman disease

Rosai Dorfman disease is a rare form of nonlangerhans cell histiocytosis, presenting with extensive lymphadenopathies. Treatment in most cases of nodal disease, involves close observation; however, extranodal involvement requires a more definitive treatment strategy. Herein, we report a case of extensive Rosai Dorfman disease in a 43-year-old woman presenting for evaluation of treatment response by 18F-FDG PET/CT after frequent relapses and disease progression. In addition to extensive lymphadenothapies in cervical, supraclavicular, superior mediastinum, axillary, abdominopelvic and inguinofemoral regions, the patient had metabolically active bone and subcutaneous lesions which were not previously recognized. Following this 18F-FDG PET/CT study, the patient management was changed to sirolimus and prednisolone. To choose the best treatment option for Rosai Dorfman patients, knowledge of the full extent of disease is important. Compared with conventional imaging, 18F-FDG PET/CT has the advantage of being a whole-body imaging modality and can recognize disease involvement prior to any anatomical changes.

Cadmium and copper heavy metal treatment from water resources by high-performance folic acid-graphene oxide nanocomposite adsorbent and evaluation of adsorptive mechanism using computational intelligence, isotherm, kinetic, and thermodynamic analyses

In this paper, folic acid-coated graphene oxide nanocomposite (FA-GO) is used as an adsorbent for the treatment of heavy metals including cadmium (Cd²⁺) and copper (Cu²⁺) ions. As such, graphene oxide (GO) is modified by folic acid (FA) to synthesize FA-GO nanocomposite and characterized by the atomic force microscopy (AFM), Fourier transform-infrared (FT-IR) spectrophotometry, scanning electron microscopy (SEM), and C/H/N elemental analyses. Also, computational intelligence tests are used to study the mechanism of the interaction of FA molecules with GO. Based on the results, FA molecules formed a strong π-π stacking, chemical, and hydrogen bond interactions with functional groups of GO. Main parameters including pH of the sample solution, amounts of adsorbent, and contact time are studied and optimized by the Response Surface Methodology Based on Central Composite Design (RSM-CCD). In this study, the equilibrium of adsorption is appraised by two (Langmuir and Freundlich and Temkin and D-R models) and three parameter (Sips, Toth, and Khan models) isotherms. Based on the two parameter evaluations, Langmuir and Freundlich models have high accuracy according to the R² coefficient (more than 0.9) in experimental curve fittings of each pollutant adsorption. But, multilayer adsorption of each contaminant onto the FA-GO adsorbent (Freundlich equation) is demonstrated by three parameter isotherm analysis. Also, isotherm calculations express maximum computational adsorption capacities of 103.1 and 116.3 mg g^-1 for Cd²⁺ and Cu²⁺ ions, correspondingly. Kinetic models are scrutinized and the outcomes depict the adsorption of both Cd²⁺ and Cu²⁺ followed by the pseudo-second-order equation. Meanwhile, the results of the geometric model illustrate that the variation of adsorption and desorption rates do not have any interfering during the adsorption process. Finally, thermodynamic studies show that the adsorption of Cu²⁺ and Cd²⁺ onto the FA-GO nanocomposite is an endothermic and spontaneous process.

The role of FDG PET/CT in the evaluation of treatment response in a case of calcified ovarian metastases

Evaluation of calcified metastatic lesions by conventional imaging can be challenging. Ovarian cancer metastases can present with calcification which might increase in size and number following therapy. It is not entirely clear whether these calcifications are associated with tumor response or disease progression. Calcified lesions which do not change in size or configuration are particularly problematic when assessed by RECIST criteria. Positron emission tomography (PET)/computed tomography (CT) is of particular value as it demonstrates the metabolic activity of the calcified lesions, in addition, it might reveal metastases in unexpected sites. We report a case of serous papillary ovarian cancer with extensive abdomino-pelvic calcified metastases referred for evaluation of therapy response. Despite being reported as stable disease on CT evaluation, we observed increased metabolic activity in the calcified lesions both on CT-attenuation corrected and non-attenuation corrected images, which was indicative of inadequate response to therapy. PET/CT is an ideal modality in follow-up of patients with ovarian cancer presenting with calcified metastatic tumoral deposits.

68Ga-DOTATATE PET/CT Compared with 131I-MIBG SPECT/CT in the Evaluation of Neural Crest Tumors

Objective(s):

⁶⁸Ga-DOTATATE positron emission tomography (PET)/computed tomography (CT) has shown promising results in imaging of neural crest tumors (NCT). Herein, we compared the performance of ⁶⁸Ga-DOTATATE PET/CT and ¹³¹I-MIBG single photon emission computed tomography (SPECT)/CT in the initial diagnosis, staging and follow-up of patients with NCTs.

Methods:

Twenty-five patients (males:females=8:17; age range=2–71 years) with clinically proven or suspicious neuroblastoma, pheochromocytoma (PCC) or paraganglioma (PGL) were enrolled in this prospective study and underwent both ⁶⁸Ga-DOTATATE PET/CT and ¹³¹I-MIBG SPECT/CT. A composite reference standard derived from histopathological information, together with anatomical and functional imaging findings, was used to validate the results. Imaging findings were assessed on a per-patient and on a per-lesion basis. Sensitivity and accuracy were assessed using McNemar’s test.

Results:

Referring to radiological imaging and histopathological findings as reference standard, ⁶⁸Ga-DOTATATE and ¹³¹I-MIBG scans showed a sensitivity and accuracy of (100%, 96%) and (86.7%, 88%), respectively, on a per-patient basis. In PCC/PGL patients, on a per-patient basis, the sensitivity of ⁶⁸Ga-DOTATATE was 100% and that of ¹³¹I-MIBG was 77.8%. In neuroblastoma patients, on a per-patient basis, the sensitivities of both ⁶⁸Ga-DOTATATE and ¹³¹I-MIBG were 100%. Overall, in this patient cohort, ⁶⁸Ga-DOTATATE PET/CT identified 52 lesions and ¹³¹I-MIBG SPECT/CT identified only 30 lesions. On a per-lesion analysis, ⁶⁸Ga-DOTATATE was found to be superior to ¹³¹I-MIBG in detecting lesions in all anatomical locations, particularly osseous lesions. According to the McNemar test results, differences were not statistically significant.

Conclusion:

This relatively small patient cohort suggests ⁶⁸Ga-DOTATATE PET/CT be superior to ¹³¹I-MIBG SPECT/CT in providing particularly valuable information for both primary staging and follow-up in patients with NCT.

Photocatalytic mineralization of hard-degradable morphine by visible light-driven Ag@g-C3N4 nanostructures

The entrance of some hard-degradable pharmaceutical contaminants can cause irreparable damage to humans and other organisms; therefore, removing these pollutants from water is one of the most important activities in water purification field. In this work, the mineralization of morphine was performed using photocatalytic degradation method. Graphitic carbon nitride (g-C₃N₄) nanosheets, due to their promising tunable characteristics, were chosen as visible-light-driven nanostructured heterogeneous photocatalyst. To enhance the photocatalytic activity, g-C₃N₄ was doped with Ag noble metal due to its surface plasmon resonance effect and acting as an electron sink. The photodegradation of morphine was evaluated under different pH values, the dosage of the photocatalyst, initial concentration of morphine, and Ag% loading under sunlight as green energy. The maximum efficiency was obtained in the very low concentration of Ag@g-C₃N₄ photocatalyst with the superior low value of 0.17 g L^-1. Near complete mineralization of morphine was achieved by Ag@g-C₃N₄ with metal content percentage equal to 5 in 180 min and pH = 2. Also, using various active species scavengers, superoxide anion radical was identified as the main responsible species in the photocatalysis reaction of morphine degradation.

Improved diagnostic accuracy for myocardial perfusion imaging using artificial neural networks on different input variables including clinical and quantification data

OBJECTIVE

Diagnostic accuracy of myocardial perfusion imaging (MPI) is not optimal to predict the result of angiography. The current study aimed at investigating the application of artificial neural network (ANN) to integrate the clinical data with the result and quantification of MPI.

METHODS

Out of 923 patients with MPI, 93 who underwent angiography were recruited. The clinical data including the cardiac risk factors were collected and the results of MPI and coronary angiography were recorded. The quantification of MPI polar plots (i.e. the counts of 20 segments of each stress and rest polar plots) and the Gensini score of angiographies were calculated. Feed-forward ANN was designed integrating clinical and quantification data to predict the result of angiography (normal vs. abnormal), non-obstructive or obstructive coronary artery disease (CAD), and Gensini score (≥10 and <10). The ANNs were designed to predict the results of angiography using different combinations of data as follows: reports of MPI, the counts of 40 segments of stress and rest polar plots, and the count of these 40 segments in addition to age, gender, and the number of risk factors. The diagnostic performance of MPI with different ANNs was compared.

RESULTS

The accuracy of MPI to predict the result of angiography, obstructive CAD, and Gensini score increased from 81.7% to 92.9%, 65.0% to 85.7%, and 50.5% to 92.9%, respectively by ANN using counts and clinical risk factors.

CONCLUSION

The diagnostic accuracy of MPI could be improved by ANN, using clinical and quantification data.

Synthesize of silver-nanoparticles by plant extract and its application for preconcentration of cadmium followed by flame atomic absorption spectrometry

In this paper, Mentha pulegium leaves extract was used as a green reducing agent for the synthesis of silver-nanoparticles. The synthesized silver-nanoparticles were characterized by UV-VIS spectrophotometry, transmission electron microscopy, X-ray spectroscopy and used as an adsorbent for preconcentration of trace levels of cadmium (ІІ). After the desorption of cadmium (ІІ) in 5 mol L^-1 formic acid, the desorbent solution was aspirated into the flame atomic absorption spectrometry for the determination of cadmium. In order to optimize the experimental condition, a response surface methodology based on central composite design was used. The optimum conditions are: pH: 8.6, amounts of adsorbent: 30 mg, 10 min extraction time and desorption time of 2 min. Under the optimum condition, the calibration curve was linear in the range of 5-200 μg L^-1 cadmium (ІІ) ion with a correlation coefficient of 0.9995. The limit of detection was 1.1 μg L^-1 and the relative standard deviation for 25 μg L^-1 cadmium (ІІ) ion was 3.0% (n = 5). In order to check the applicability of the proposed method, different real samples were analyzed. Also, the accuracy of this method was successfully checked by the analysis of certified reference material and spike tests.

Designing a smart risk analysis method for gas chlorination units of water treatment plants with combination of Failure Mode Effects Analysis, Shannon Entropy, and Petri Net Modeling

Today, all modern industrial units acknowledge the necessity of efficient and effective safety, health, and environment (HSE) systems. To become practical, these systems must be localized and customized to serve the exact needs of the industry. Nevertheless, most HSE plans are developed upon a set of common presumptions. In the water industry, gas chlorination units require strong HSE plans to mitigate the possibility of chlorine explosion and leak. This study aimed to provide an efficient HSE system for gas chlorination process within water treatment plants. This goal was achieved through a case study performed on a water treatment plant in Razavi-Khorasan province, Iran. In the first stage of this study, the researchers made combined use brainstorming sessions and modified Delphi technique to identify the risk factors of gas chlorination units and classify them into six groups in terms of association with chlorination unit building, gas cylinder storage, technical details of gas cylinders, gas cylinder transport, chlorinator connections, and chlorination unit management. In the second stage, the extracted factors were analyzed by Failure Mode Effects Analysis (FMEA) and Shannon Entropy approaches using two different panels of experts, and the results were compared for validation. Finally, the analysis results were structured by Petri Net modeling. The results showed that, according to FMEA, the risk factors with risk priority number (RPN) of over 46 are of highest importance for the studied unit. Once observed, these factors necessitate shutting down the operation until a risk mitigation solution is reached. Among the analyzed factors, (i) the presence of compounds such as NH₃, O₂, gas and liquid hydrocarbons and oil in gas chlorine cylinders and (ii) non-vertical and non-mechanized handling of full and empty cylinders during loading and unloading, with RPNs of respectively 160 and 120, were found to be significantly more important than others. In the SE analysis, in addition to the above factors, poor implementation of airflow control mechanism inside the chlorination chamber (W = 0.359), storage of chlorine cylinders near electrical and mechanical installations such as elevators or power panels (W = 0.327), poor pipe placement for connecting the injector to the water inlet and the possibility of air suction (W = 0.433), and failure to provide scientific and practical training to the chlorination staff (W = 0.342) were found to be of highest importance.

Experimental investigation and mathematical modeling for microbial removal using potassium permanganate as an oxidant-case study: water treatment plant No. 1, Mashhad, Iran

Preoxidation is an important unit process which can partially remove organic and microbial contaminations. Due to the high concentrations of organic matter entering the water treatment plant, originating from surface water resources, preoxidation by using chlorinated compounds may increase the possibility of trihalomethane (THM) formation. Therefore, in order to reduce the concentration of THMs, different alternatives such as injection of potassium permanganate are utilized. The present study attempts to investigate the efficiency of the microbial removal from raw water entering the water treatment plant No. 1 in Mashhad, Iran, through various doses of potassium permanganate. Then, an examination of the predictive models is done in order to indicate the residual Escherichia coli and total coliform resulted from injecting the potassium permanganate. Finally, the coefficients of the proposed models were optimized using the genetic algorithm. The results of the study show that 0.5 mg L^-1 of potassium permanganate would remove 50% of total coliform as well as 80% of Escherichia coli in the studied water treatment plant. Also, assessing the performance of different models in predicting the residual microbial concentration after injection of potassium permanganate suggests the Gaussian model as the one resulting the highest conformity. Moreover, it can be concluded that employing smart models leads to an optimization of the injected potassium permanganate at the levels of 27% and 73.5%, for minimum and maximum states during different seasons of a year, respectively.

Automated Interpretation of Myocardial Perfusion Images with Multilayer Perceptron Network as a Decision Support System

Aim: Bull's eye pattern recognition with artificial neural networks (ANNs) has the potential to assist interpretation of myocardial perfusion images (MPIs). We aimed to develop a model for interpretation of MPI based on the clinical variables and imaging data. Materials and Methods: The study included 208 patients referred to the department of nuclear medicine for 2-day stress-rest ECG-gated MPI. Several ANN models were designed with the following input variables: average count of 20 segments of the bull's eye images of stress and rest MPIs, gender, the constellation of coronary artery disease risk factors and scintigraphic cardiac ejection fraction. The procedure was repeated excluding the data of the rest phase scan. Data of 150 subjects were used for training, 21 subjects for cross-validation and 37 subjects for final operation testing. Several ANN models were examined with different hidden layers and processing elements and functions. The target output variable was the conclusion of the nuclear physician (i.e., normal vs. abnormal scan). Results: A multilayer perceptron (MLP) with two hidden layers trained with both stress and rest data demonstrated the best performance to classify the normal and abnormal MPIs. It showed an overall accuracy of 91.9%, sensitivity of 91.3% and specificity of 92.9%. The accuracy of the similar MLP trained using stress-only myocardial perfusion images reduced to 67.6%. Conclusion: The automated interpretation of MPIs with a 2 hidden layer MLP trained with stress and rest images could be an accurate support system either for the interpretation or quality assurance.

Brain Perfusion Single Photon Emission Computed Tomography Findings in Patients with Posttraumatic Anosmia and Comparison with Radiological Imaging

Background

Different techniques in neuroimaging have been proposed for assessment of olfactory dysfunction but they are not without limitations. Recently, some studies showed the usefulness of single photon emission–computed tomography (SPECT) in evaluation of patients with posttraumatic anosmia. This study was designed to assess the possible diagnostic value of SPECT findings in patients with posttraumatic anosmia in comparison with magnetic resonance imaging (MRI)/CT imaging.

Methods

Sixteen patients who had head trauma and consequently anosmia, which was defined according to Cain's identification test, were included in this study. Two nonanosmic groups, traumatic patients and nontraumatic healthy individuals, were selected as control groups for this study. Qualitative and semiquantitative brain perfusion SPECT was performed by measuring the uptake ratio of the orbital frontal cortex to occipital pole in the sagittal projections (uptake index). All 16 target patients had a previous CT scan and/or MRI. Semiquantitative and qualitative brain perfusion SPECT were compared with radiological imaging.

Results

Semiquantitative assessment of brain perfusion SPECT revealed remarkable orbital frontal hypoperfusion as compared with two control groups. 87.5% of anosmic patients showed orbital frontal hypoperfusion (≥2 SD below the lowest level in healthy controls). In addition, the semiquantitative SPECT method detected more orbitofrontal abnormality than the qualitative method or radiological imaging (MRI and/or CT).

Conclusion

Findings suggest that by using SPECT, posttraumatic anosmia corresponds to the hypoperfusion in the orbital frontal cortex in a great number of patients. Because of its availability, rather low cost, technical ease, and possibility to obtain objective quantitative information, brain perfusion SPECT can be complementary to other diagnostic techniques in the evaluation of olfactory function, although additional neurophysiological and imaging studies are needed.

POPULATION RADIATION EXPOSURE FROM DIAGNOSTIC NUCLEAR MEDICINE PROCEDURES IN TEHRAN 2011-14; TRENDS IN THE LAST 3 DECADES

This study represents an update of Tehran population exposure from the diagnostic nuclear medicine procedures and the annual collective effective dose during 2011-14. The diagnostic nuclear medicine procedures data were collected from 58 out of 60 nuclear medicine centers in Tehran and were composed of the type and frequency of diagnostic examinations, radiopharmaceuticals used, administered activities, and age distribution of the patients. The annual number of examinations per 1000 population increased from 13.73 in 2011 to 22.59 in 2014 with an increase of 64.53% during 4 years. Most frequent examinations were cardiac (71.05%), bone (9.80%) and thyroid (7.26%) averaged over the 5 years. The collective effective dose increased from 807.74 person-Sv in 2011 to 1413.81 person-Sv in 2014. The effective dose per capita increased from 44.06 μSv in 2011 to 120.91 μSv in 2014, could be because of 70% increase of examinations, but ~3.42% increase in the population of Tehran.

Solid-phase extraction of ultra-trace levels of lead using tannic acid-coated graphene oxide as an efficient adsorbent followed by electrothermal atomic absorption spectrometry; response surface methodology – central composite design

Tannic acid-coated graphene oxide as a novel and powerful adsorbent for the removal of lead.

Production and Clinical Applications of Radiopharmaceuticals and Medical Radioisotopes in Iran

During past 3 decades, nuclear medicine has flourished as vibrant and independent medical specialty in Iran. Since that time, more than 200 nuclear physicians have been trained and now practicing in nearly 158 centers throughout the country. In the same period, Tc-99m generators and variety of cold kits for conventional nuclear medicine were locally produced for the first time. Local production has continued to mature in robust manner while fulfilling international standards. To meet the ever-growing demand at the national level and with international achievements in mind, work for production of other Tc-99m-based peptides such as ubiquicidin, bombesin, octreotide, and more recently a kit formulation for Tc-99m TRODAT-1 for clinical use was introduced. Other than the Tehran Research Reactor, the oldest facility active in production of medical radioisotopes, there is one commercial and three hospital-based cyclotrons currently operational in the country. I-131 has been one of the oldest radioisotope produced in Iran and traditionally used for treatment of thyrotoxicosis and differentiated thyroid carcinoma. Since 2009, (131)I-meta-iodobenzylguanidine has been locally available for diagnostic applications. Gallium-67 citrate, thallium-201 thallous chloride, and Indium-111 in the form of DTPA and Oxine are among the early cyclotron-produced tracers available in Iran for about 2 decades. Rb-81/Kr-81m generator has been available for pulmonary ventilation studies since 1996. Experimental production of PET radiopharmaceuticals began in 1998. This work has culminated with development and optimization of the high-scale production line of (18)F-FDG shortly after installation of PET/CT scanner in 2012. In the field of therapy, other than the use of old timers such as I-131 and different forms of P-32, there has been quite a significant advancement in production and application of therapeutic radiopharmaceuticals in recent years. Application of (131)I-meta-iodobenzylguanidine for treatment of neuroblastoma, pheochromocytoma, and other neuroendocrine tumors has been steadily increasing in major academic university hospitals. Also (153)Sm-EDTMP, (177)Lu-EDTMP, (90)Y-citrate, (90)Y-hydroxyapatite colloid, (188/186)Re-sulfur colloid, and (188/186)Re-HEDP have been locally developed and now routinely available for bone pain palliation and radiosynovectomy. Cu-64 has been available to the nuclear medicine community for some time. With recent reports in diagnostic and therapeutic applications of this agent especially in the field of oncology, we anticipate an expansion in production and availability. The initiation of the production line for gallium-68 generator is one of the latest exciting developments. We are proud that Iran would be joining the club of few nations with production lines for this type of generator. There are also quite a number of SPECT and PET tracers at research and preclinical stage of development preliminarily introduced for possible future clinical applications. Availability of fluorine-18 tracers and gallium-68 generators would no doubt allow rapid dissemination of PET/CT practices in various parts of our large country even far from a cyclotron facility. Also, local production and availability of therapeutic radiopharmaceuticals are going to open exciting horizons in the field of nuclear medicine therapy. Given the available manpower, local infrastructure of SPECT imaging, and rapidly growing population, the production of Tc-99m generators and cold kit would continue to flourish in Iran.

Utilizing the micron sized non-thermal atmospheric pressure plasma inside the animal body for the tumor treatment application

This study aimed to evaluate the effects of micron sized non-thermal atmospheric pressure plasma inside the animal body on breast cancer tumor. The μ-plasma jet consists of micron sized hollow tube in which pure helium gas is ionized by high voltage (4 kV) and high frequency (6 kHz). The efficiency of the plasma treatment in killing cancer cells was first investigated by cell viability measurements of treated 4T1 cells using flow cytometry and cell cycle analysis. For exploration of the in vivo effects of the plasma treatment, the BALB/c mice inoculated by 4T1 cell lines were exposed subcutaneously to plasma for 3 minutes. In addition, H&E staining, TUNEL and Western blotting assays were performed in order to observed the effects of the non-thermal plasma on the tumor cells. The results showed that the efficiency of the plasma in suppression of the tumor growth is comparable to that of a typical chemotherapy drug. Moreover, the results indicated that the plasma induces apoptosis in the tumor tissue and increases the ratio of the apoptotic to anti-apoptotic protein expression. We believe that these findings presented herein may extend our knowledge of the mechanisms by which the plasma exerts its promising anti-cancer effects.

Predicting In vitro Culture Medium Macro-Nutrients Composition for Pear Rootstocks Using Regression Analysis and Neural Network Models

Two modeling techniques [artificial neural network-genetic algorithm (ANN-GA) and stepwise regression analysis] were used to predict the effect of medium macro-nutrients on in vitro performance of pear rootstocks (OHF and Pyrodwarf). The ANN-GA described associations between investigating eight macronutrients (NO[Formula: see text], NH[Formula: see text], Ca(2+), K(+), Mg(2+), PO[Formula: see text], SO[Formula: see text], and Cl(-)) and explant growth parameters [proliferation rate (PR), shoot length (SL), shoot tip necrosis (STN), chlorosis (Chl), and vitrification (Vitri)]. ANN-GA revealed a substantially higher accuracy of prediction than for regression models. According to the ANN-GA results, among the input variables concentrations (mM), NH[Formula: see text] (301.7), and NO[Formula: see text], NH[Formula: see text] (64), SO[Formula: see text] (54.1), K(+) (40.4), and NO[Formula: see text] (35.1) in OHF and Ca(2+) (23.7), NH[Formula: see text] (10.7), NO[Formula: see text] (9.1), NH[Formula: see text] (317.6), and NH[Formula: see text] (79.6) in Pyrodwarf had the highest values of VSR in data set, respectively, for PR, SL, STN, Chl, and Vitri. The ANN-GA showed that media containing (mM) 62.5 NO[Formula: see text], 5.7 NH[Formula: see text], 2.7 Ca(2+), 31.5 K(+), 3.3 Mg(2+), 2.6 PO[Formula: see text], 5.6 SO[Formula: see text], and 3.5 Cl(-) could lead to optimal PR for OHF and optimal PR for Pyrodwarf may be obtained with media containing 25.6 NO[Formula: see text], 13.1 NH[Formula: see text], 5.5 Ca(2+), 35.7 K(+), 1.5 Mg(2+), 2.1 PO[Formula: see text], 3.6 SO[Formula: see text], and 3 Cl(-).

Evaluation of (99m)Tc-TRODAT-1 SPECT in the diagnosis of Parkinson's disease versus other progressive movement disorders

OBJECTIVE

Parkinson disease (PD), parkinsonian syndromes (PS) and essential tremor (ET) are different types of movement disorders which share some symptoms resulting in a difficulty of certain diagnosis. This study was conducted to determine the value of (99m)Tc-TRODAT-1 scan to differentiate PD from ET and other PS cases.

METHODS

Totally, 75 patients were studied including 29 PD, 6 possible PD, 22 ET and 18 PS cases. A dual-head SPECT-CT was used to perform basal ganglia (BG) imaging following administration of (99m)Tc-TRODAT-1. The BG uptake values were normalized to whole brain and occipital activity. All patients were followed for 2-22 months to reach a certain diagnosis.

RESULTS

Patients with ET and drug-induced parkinsonism show significantly higher normalized BG uptake as compared to the other subgroups; however, no significant difference was noted between PD and PS patients. The sensitivity and specificity of the findings for the differentiation between patients with the disease associated versus not associated with BG dysfunction were 80 and 83.3%, respectively. A predictive positive value of 82.6% was obtained using an additive scaling index defined as asymmetry and unevenness of uptake in putamen and/or caudate contralateral to the dominant side of current symptoms.

CONCLUSIONS

(99m)Tc-TRODAT-1 scan is an appropriate method to differentiate PD or PS versus ET. A combination of scan pattern including asymmetry of BG uptake and unevenness of activity in caudate and putamen along with the side of dominant symptoms may be valuable for the differentiation of Parkinson's disease from the other parkinsonian syndromes.