Journal articles: 'Radioisotope scanning'

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MITTAL, BHAGWANT R., DHEERAJ GUPTA, and SURINDER K. JINDAL. "Radioisotope Bone Scanning in Pulmonary Alveolar Microlithiasis." Clinical Nuclear Medicine 25, no. 6 (June 2000): 474–75. http://dx.doi.org/10.1097/00003072-200006000-00019.

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BENELHADJ, SALAH, FRÉDÉRIC PATROIS, MICHÈLE DUET, BRUNO BÉROLATTI, and OLIVIER MUNDLER. "Radioisotope Bone Scanning in Chronic Osseous Sarcoidosis." Clinical Nuclear Medicine 21, no. 5 (May 1996): 371–74. http://dx.doi.org/10.1097/00003072-199605000-00004.

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CINTI, DOROTHY C., HAROLD B. HAWKINS, and JAMES D. SLAVIN. "Radioisotope Bone Scanning in a Case of Sarcoidosis." Clinical Nuclear Medicine 10, no. 3 (March 1985): 192–94. http://dx.doi.org/10.1097/00003072-198503000-00014.

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Moriyama, Eiji, Tomoyuki Ogawa, Ayumi Nishida, Shinichi Ishikawa, and Hiroichi Beck. "Quantitative analysis of radioisotope cisternography in the diagnosis of intracranial hypotension." Journal of Neurosurgery 101, no. 3 (September 2004): 421–26. http://dx.doi.org/10.3171/jns.2004.101.3.0421.

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Object. The authors attempted a quantitative analysis of conventional radioisotope cisternography for the purpose of more accurate diagnosis of intracranial hypotension. Methods. Fifty-seven patients suspected of having intracranial hypotension underwent radioisotope cisternography. Whole-body images were obtained 2.5, 6, and 24 hours after intrathecal injection of 111In—diethylenetriamine pentaacetic acid. Radioactivity in the cerebrospinal fluid (CSF) space was counted during scanning, and radioisotope clearance was studied. Direct signs of radioisotope leakage into the spinal epidural space were found in 25 patients. Most leaks were located in the lumbosacral region. Analysis of the radioisotope clearance curve revealed two different patterns. In patients without a radiographically demonstrated radioisotope leak, absolutely exponential curves were observed (R2 > 0.99). The activity of the radioisotope decreased at a rate of e−0.03 to e−0.107 (mean ± standard deviation, e−0.056 ± 0.018; 32 patients). Clearance in patients with an overt radioisotope leak was not a simple exponential curve; it could be divided into an early rapid phase and a late slow phase. The clearance rate during the first 6 hours was e−0.219 ± 0.127 (25 patients) and e−0.076 ± 0.021 thereafter. The authors speculated that the early escape of undiluted radioisotope solution through an aberrant CSF outlet, such as a traumatic spinal dural tear, was responsible for this phenomenon. Conclusions. The quantitative analysis featured in this study seems to be useful in the diagnosis of intracranial hypotension. A small CSF leak below the limit of radioisotope cisternography resolution might be detected using this technique.

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Mohammed, Mohammed Siddig H., Essam M. Banoqitah, Ezzat Elmoujarkach, Abdulsalam M. Alhawsawi, and Fathi Djouider. "A virtual laboratory for radiotracer and sealed-source applications in industry." Nukleonika 66, no. 1 (March 1, 2021): 21–27. http://dx.doi.org/10.2478/nuka-2021-0003.

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Abstract Radioactive sealed sources and radiotracer techniques are used to diagnose industrial process units. This work introduces a workspace to simulate four sealed sources and radiotracer applications, namely, gamma scanning of distillation columns, gamma scanning of pipes, gamma transmission tomography, and radiotracer flow rate measurements. The workspace was created in Geant4 Application for Tomographic Emission (GATE) simulation toolkit and was called Industrial Radioisotope Applications Virtual Laboratory. The flexibility of GATE and the fact that it is an open-source software render it advantageous to radioisotope technology practitioners, educators, and students. The comparison of the simulation results with experimental results that are available in the literature showed the effectiveness of the virtual laboratory.

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Zincirkeser, Sabri, Zeki Çelen, Mustafa Yılmaz, and Ercan Sivaslı. "Diagnoses of false negative Meckel's diverticulum in a 14 month old boy using radioisotope scanning." European Journal of Therapeutics 13, no. 1 (January 1, 2007): 5–7. http://dx.doi.org/10.58600/eurjther.2007-13-1-1397-arch.

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A 14-month-old boy with painless rectal bleeding for two days was referred to our department. He had an equivocal Meckel's diverticulum which showed rapid washout of activity on radioisotope scan. This scintigraphic finding was later confirmed on surgery and histopathologically. Radioisotope scanning with pertechnetate is a simple, non-invasive and valuable test for pre-operative diagnosis of Meckel's diverticulum. However, rapid Tc99m-pertechnetate washout may be one of false negative causes. if in doubt, study should be repeated the next day and it is more convenient to image patient in prone position and dynamic oblique views should be taken.

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Hirnle, P., K. P. Mittmann, B. Schmidt, and K. H. Pfeiffer. "Indications for radioisotope bone scanning in staging of cervical cancer." Archives of Gynecology and Obstetrics 248, no. 1 (September 1990): 21–23. http://dx.doi.org/10.1007/bf02389585.

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Askarova, Anna A., Viktor N. Nikolkin, Denis S. Butakov, Leonid P. Sinelnikov, and Vladimir N. Rychkov. "Sr-doped carbon matrices for use as electrodes in autonomous electrical energy sources." Bulletin of the Tomsk Polytechnic University Geo Assets Engineering 335, no. 6 (June 27, 2024): 135–42. http://dx.doi.org/10.18799/24131830/2024/6/4355.

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Relevance. The need to create new safe energy sources that can meet the needs of production and medicine where the use of traditional energy sources is impossible or unprofitable. Such sources may include radioisotope power sources, in which energy production is ensured by the natural decay of radionuclides. The most important components of current sources such as supercapacitors are electrode materials, the characteristics of which determine the electrophysical characteristics of radioisotope sources. This work proposes a method for synthesizing a carbon matrix doped with Sr for use as electrodes of radioisotope power sources. Aim. Development, mastery and optimization of a method for synthesizing electrodes of radioisotope power sources based on carbon materials doped with the Sr-90 radioisotope. Objects. Carbon material doped with a radioisotope simulant Sr-90 (Sr stable). Carbon matrices were obtained by carbonizing a resorcinol-formaldehyde resin doped with a stable strontium salt. Methods. Scanning electron microscopy, low-temperature adsorption-desorption of nitrogen, cyclic voltammetry, galvanostatic charge-discharge, impedance microscopy. Results. A carbon matrix doped with a stable strontium isotope was synthesized by the method of semi-carbonization followed by physical activation with carbon dioxide. The structure, porosity and electrochemical characteristics of the material were studied. It was established that physical activation has a positive effect on the development of the specific surface area and mesoporosity of the samples of the synthesized matrix, as a result of which its electrochemical characteristics are improved. The method of physical activation is proposed as the most preferable for the synthesis of a carbon matrix doped with strontium isotopes for use as electrodes of radioisotope power supplies.

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Zingade, Dr Anand P., Dr Manish Kumar, Dr Rohit S. Shool, and Dr Ajit G. Jadhav. "Role of Radioisotope Scanning (DMSA and DTPA) in the Diagnosis and Management of Pediatric Urology Cases." Indian Journal of Applied Research 3, no. 5 (October 1, 2011): 463–64. http://dx.doi.org/10.15373/2249555x/may2013/143.

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Brown, Orval E. "Radioisotope Scanning of the Thyroid Gland Prior to TGD Cyst Excision." Archives of Otolaryngology–Head & Neck Surgery 124, no. 5 (May 1, 1998): 600. http://dx.doi.org/10.1001/archotol.124.5.600.

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Tunkel, David E., and Edgar E. Domenech. "Radioisotope Scanning of the Thyroid Gland Prior to Thyroglossal Duct Cyst Excision." Archives of Otolaryngology–Head & Neck Surgery 124, no. 5 (May 1, 1998): 597. http://dx.doi.org/10.1001/archotol.124.5.597.

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Axelsson, C. K., B. P. Nielsen, and J. Graff. "Radioisotope-Guided Surgical Biopsy of Costal Metastases in Breast Cancer Patients." Scandinavian Journal of Surgery 91, no. 4 (December 2002): 333–35. http://dx.doi.org/10.1177/145749690209100404.

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Radioisotope bone scanning is a sensitive indicator of metastatic disease. Localization of the hot spot for biopsy is difficult. Today, a hand-held gamma probe enables the surgeon intraoperatively to accomplish the localization procedure easily. As this technique is described in American literature exclusively, more recent European findings is presented here. During one month two patients were diagnosed with breast cancer. Bone scanning disclosed minor hot spots in the ribs. On the day of surgical biopsy the localization of the hot spots was guided by a gamma probe. For the biopsy a dermal punch biopsy needle was employed, and fine needle aspiration biopsies were also taken. The procedures were easy and completed within a few minutes. The post-operative courses were uneventful. In one patient, final histology showed malignancy in both biopsies. In the other patient, only the fine needle aspiration biopsy was malignant. The punch biopsy was abnormal, but did not contain malignant tissue. The gamma probe is an important tool in the performance of rib biopsies of nonpalpable lesions. The punch biopsy technique is simple and combined with fine needle aspiration biopsy the method has proven to be sensitive and accurate. The punch biopsy technique furthermore reduces the risk of postoperative pneumothorax.

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Robinson, Lary A. "Radioisotope-Guided Surgical Biopsy of Suspected Osseous Metastases." Cancer Control 4, no. 6 (November 1997): 516–22. http://dx.doi.org/10.1177/107327489700400605.

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Background Radioisotope bone scanning is frequently used to stage patients with suspected or proven malignancies. Since false-positive results are common, especially in the ribs, open biopsy is often necessary. The conventional approach of visual inspection of the bone scan image to guide the surgeon usually requires excision of a large area of one or two ribs to assure that the biopsy was performed on the correct rib. A more precise method to guide the biopsy is desirable. Methods One technique to localize the suspicious area of bone intraoperatively for accurate biopsy involves percutaneous injection of the bone abnormality with a radioisotope followed by injection of methylene blue into the periosteum and subsequent open surgical biopsy. A more recent technique uses a hand-held gamma probe in a sterile sleeve in the operating room to locate the bone “hot spot” directly in the wound to guide the biopsy. Results Both techniques are effective in pinpointing the bone scan abnormality, but use of the gamma probe is less cumbersome and consumes less time and fewer resources. In one series of 10 patients undergoing gamma probe-guided biopsies of 13 rib and 1 sternal bone scan lesions, this technique showed a sensitivity of 100% in locating the area of abnormal radioisotope uptake. All biopsies yielded an abnormal diagnosis to account for the bone scan abnormality, but only 4 of 14 (29%) demonstrated metastatic tumor. Conclusions Techniques described for radioisotope-guided localization of areas of increased tracer uptake in asymptomatic suspected bone metastases are accurate, sensitive guides to the open biopsy of these bony abnormalities. Due to the high false-positive rates in these asymptomatic but suspicious bone scan abnormalities, a diagnosis should be histologically confirmed.

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Michel, F., M. Soler, E. Imhof, and A. P. Perruchoud. "Initial staging of non-small cell lung cancer: value of routine radioisotope bone scanning." Thorax 46, no. 7 (July 1, 1991): 469–73. http://dx.doi.org/10.1136/thx.46.7.469.

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du Toit, J. P., M. Med, and D. V. Grove. "Radioisotope bone scanning for the detection of occult bony metastases in invasive cervical carcinoma." Gynecologic Oncology 28, no. 2 (October 1987): 215–19. http://dx.doi.org/10.1016/0090-8258(87)90216-2.

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Skaar, Ø., K. Dale, M. W. Lindegaard, O. Førre, and E. Kåss. "Quantitative Radio-Isotope Scanning of the Sacroiliac Joints in Ankylosing Spondylitis." Acta Radiologica 33, no. 2 (March 1992): 169–71. http://dx.doi.org/10.1177/028418519203300219.

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A method for applying 99mTc-MDP for dynamic and static quantitative radioisotope scanning (QRS) of the sacroiliac joints (SI) in early progressive sacroiliitis in ankylosing spondylitis (AS) is described. In a prospective study, 2 groups of male AS patients were investigated, one with increased elevated erythrocytic sedimentation rate (ESR) (group A, n = 7) and one with normal ESR (group B, n = 8). In both groups an increased uptake of the radiotracer was found in the static part of the study versus a control group C (n = 9). An increased uptake versus group C was also found for group A in the dynamic part of the study (p = 0.01) while there was no significant difference dynamically between groups B and C. The results of the dynamic study in group A indicate ESR to be a parameter of inflammatory activity in the SI joints. The study also seems to indicate QRS to be a valuable diagnostic method in early AS without definite radiographic changes in the SI joints.

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Aldaghri, O., E. Y. Salih, A. Ramizy, M. F. M. Sabri, N. Madkhali, T. Alinad, K. H. Ibnaouf, and M. H. Eisa. "Morphological characteristics of β-irradiated lead oxide nano-sized particles." Digest Journal of Nanomaterials and Biostructures 17, no. 1 (January 2022): 29–37. http://dx.doi.org/10.15251/djnb.2022.171.29.

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This work examined the beta irradiation and characterization of lead oxide nanoparticles samples that were prepared via pulsed laser deposition. The lead oxide nanoparticles samples were irradiated by beta-ray. Strontium 90 radioisotope was used as beta irradiation for different time periods (Days 1, 3, 4, and 5). The morphologies of lead oxide nanoparticles films were characterized with and without beta irradiation through the use of scanning electron microscope (SEM) and atomic force microscopy (AFM). According to the findings, beta radiation impacted lead oxide nanoparticles samples’ morphological properties. The details of experimental setups, sample preparation procedures, and data analysis, are explicated.

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Sebastián Calvo, Carlos. "Implementation of ISO 9001:2000 quality management system as applied to gamma scanning technique for inspecting fractionning columns and related unit process operations." Scientia 19, no. 19 (November 28, 2018): 123–36. http://dx.doi.org/10.31381/scientia.v19i19.1749.

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Product manufacturers and service providers have to follow certain procedures and protocols to guarantee the quality products and services to satisfy consumer requirements. Standards contribute by making development, manufacturing and supply of products and services more efficient, safer and competitive. The quality assessment and quality control system in radioisotope applications consists of enhanced quality awareness, better presentation of documentation, establishment of standard operating manuals, and preparation of procedures for validation of methods, surveillance of method performance and formulation of protocols for experimental design and execution, regular qualification of personnel, client liaison and safety.

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Cox, Kenneth L., Robert C. Stadalnik, John P. McGahan, Kathleen Sanders, Robert A. Cannon, and Boris H. Ruebner. "Hepatobiliary Scintigraphy with Technetium‐99m Disofenin in the Evaluation of Neonatal Cholestasis." Journal of Pediatric Gastroenterology and Nutrition 6, no. 6 (November 1987): 885–91. http://dx.doi.org/10.1002/j.1536-4801.1987.tb09429.x.

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SummaryTo assess the reliability of technetium‐99m disofenin scanning in evaluating neonatal cholestasis. 33 neonates (3 months of age) with direct hyperbilirubinemia were evaluated prospectively by cholescintigraphy. Results of this test were compared to those of standard serum tests of liver function, ultrasonography, and liver biopsy. The diagnosis of biliary atresia was suggested by a serum γ‐glutamyl transpeptidase (γ‐GTP) 300 units, absence of the gallbladder on ultrasonography, and a lack of delectable radioisotope in the gastrointestinal and or extrahepatic biliary tract on cholescintigraphy. Each of these tests lacked sensitivity and or specificity when compared to liver biopsy. Of the nine neonates with biliary atresia, three had gallbladders identified In ultrasonography and two had γ‐GTP 300 units Of the 24 neonates without biliary atresia, eight had cholescintigraphy without detectable radioisotope excretion, four had ultrasonography that failed to visualize the gallbladder, and nine had γ‐GTP 300 units. Cholescintigraphy excluded the diagnosis of biliary atresia when gut and or extrahepatic biliary excretion of isotope was seen. However, cholescintigraphy required more time. 6–8 days, and was less specific than ultrasonography and liver biopsy. We recommend that cholescintigraphy should not be routinely used in evaluating neonatal cholestasis, especially if it delays surgical intervention.

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Mawar, Mawar, Sri Dewi Astuti, and Siska Febriana. "Deteksi Karakteristik Peluruhan Radionuklida Medis 99Mo Untuk Memperoleh 99mTc Menggunakan Spektrometer Gamma dengan Sumber Standar Cair Campuran 133Ba dan 152Eu." Jurnal Fisika Indonesia 24, no. 2 (August 31, 2020): 96. http://dx.doi.org/10.22146/jfi.v24i2.54405.

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Technetium-99m (99mTc) is a subsidiary of metastable 99Mo with a half-life of 6 hours. The relatively short half-life, causing 99mTc widely used for diagnostic purposes in nuclear medicine, especially in bone scanning for a faster decay. This research aims to determine the optimal time to product formation of 99mTc until elution profiles have detected 99Mo energy. The instrument used is the 99Mo/99mTc generator with standard sources 133Ba and 152Eu liquid mixture. The results obtained showed that 99mTc radioisotope production is still good until the third day elution 99Mo, whereas in the fourth to ninth day 99Mo energy detected on the decline, so that the activity of the 99mTc resulting product cannot be used for diagnosis.

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Amendy, U., and D. Dunlop. "Poster abstracts: pictorial reviews The value of the pelvic outlet or squat view in radioisotope bone scanning." Nuclear Medicine Communications 25, no. 3 (March 2004): 319–20. http://dx.doi.org/10.1097/00006231-200403000-00055.

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Sawka, Anna M. "Iodine Radioisotope Diagnostic Scanning With SPECT/CT After Thyroidectomy for Thyroid Cancer: Essential Data or Unnecessary Investigation?" Journal of Clinical Endocrinology & Metabolism 98, no. 3 (March 1, 2013): 958–60. http://dx.doi.org/10.1210/jc.2013-1329.

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Herbst, F., M. A. Kamm, G. P. Morris, K. Britton, J. Woloszko, and R. J. Nicholls. "Gastrointestinal transit and prolonged ambulatory colonic motility in health and faecal incontinence." Gut 41, no. 3 (September 1, 1997): 381–89. http://dx.doi.org/10.1136/gut.41.3.381.

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Background—Colonic motor function has not been studied in the ambulatory setting over a prolonged period in the unprepared state. Furthermore, the disturbance of this function in patients with faecal incontinence is unknown.Aim—To study colonic function over two to three days in the ambulatory, unprepared state in health and in patients with idiopathic faecal incontinence.Methods—Six healthy women and six women with faecal incontinence and a structurally intact anal sphincter ingested a dual radioisotope meal, and had a six sensor, solid state manometric probe colonoscopically inserted into the left colon. Scanning was performed until radioisotope left the gut and pressure was recorded for a median of 44 hours.Results—Three of six patients showed abnormal gastric emptying. Patients showed no disturbance of colonic radioisotope transit. Controls had a median of 12, whereas patients had a median of 16, high amplitude propagated waves per 24 hours. In three patients urge incontinence was associated with high amplitude (up to 500 cm water) propagated waves which often reached the rectum. These high pressure waves were identical to those occuring in healthy subjects, the only difference being the lack of adequate sphincter response. Passive incontinence was not associated with colonic motor activity. Defaecation in all subjects was associated with identical propagated waves, and distal movement of 13% (median) of right colonic content and excretion of 32% from the left colon and rectum. The urge to defaecate was associated with either propagated waves (45%) or non-propagated contractions (55%). Rectal motor complexes were recorded in both groups of subjects, but similar rhythmic activity was also recorded in the sigmoid and descending colon.Conclusions—Normal colonic function consists of frequent high pressure propagated waves. Rhythmic activity occurs both proximal to and in the rectum. Defaecation is characterised by high pressure propagated waves associated with coordinated anal sphincter relaxation. Patients with faecal incontinence may have a widespread disturbance of gut function. Urge incontinence, an urge to defaecate, and defaecation can all be associated with identical high amplitude propagated pressure waves.

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Jorissen, Mark. "Correlations among Mucociliary Transport, Ciliary Function, and Ciliary Structure." American Journal of Rhinology 12, no. 1 (January 1998): 53–58. http://dx.doi.org/10.2500/105065898782102945.

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Mucociliary transport is one of the most important defense mechanisms of the airway. Mucociliary transport time or rate, as measured using the saccharin test or the radioisotope technique, respectively, is clinically the most relevant parameter, although subject to large intra- and interindividual variability. There is no correlation between mucociliary transport in vivo and ciliary beat frequency ex vivo. Preliminary evidence demonstrates that mucociliary transport correlates with ciliary structure and orientation as investigated with transmission and scanning electron microscopy. A correlation is presented between ciliary beat frequency and secondary ciliary abnormalities. This correlation can best be described according to the logistic sigmoid model (r = 0.69). Based on these functional data, an ultrastructural distinction is proposed among normal (less than 5%), light (5 to 15%), moderate (15 to 25%), and severe (more than 25%) secondary ciliary dyskinesia.

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Rotariu, Traian, Daniela Pulpea, Gabriela Toader, Edina Rusen, Aurel Diacon, Valentina Neculae, and John Liggat. "Peelable Nanocomposite Coatings: “Eco-Friendly” Tools for the Safe Removal of Radiopharmaceutical Spills or Accidental Contamination of Surfaces in General-Purpose Radioisotope Laboratories." Pharmaceutics 14, no. 11 (November 1, 2022): 2360. http://dx.doi.org/10.3390/pharmaceutics14112360.

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Radioactive materials are potentially harmful due to the radiation emitted by radionuclides and the risk of radioactive contamination. Despite strict compliance with safety protocols, contamination with radioactive materials is still possible. This paper describes innovative and inexpensive formulations that can be employed as ‘eco-friendly’ tools for the safe decontamination of radiopharmaceuticals spills or other accidental radioactive contamination of the surfaces arising from general-purpose radioisotope handling facilities (radiopharmaceutical laboratories, hospitals, research laboratories, etc.). These new peelable nanocomposite coatings are obtained from water-based, non-toxic, polymeric blends containing readily biodegradable components, which do not damage the substrate on which they are applied while also displaying efficient binding and removal of the contaminants from the targeted surfaces. The properties of the film-forming decontamination solutions were assessed using rheological measurements and evaporation rate tests, while the resulting strippable coatings were subjected to Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and tensile tests. Radionuclide decontamination tests were performed on various types of surfaces encountered in radioisotope workspaces (concrete, painted metal, ceramic tiles, linoleum, epoxy resin cover). Thus, it was shown that they possess remarkable properties (thermal and mechanical resistance which permits facile removal through peeling) and that their capacity to entrap and remove beta and alpha particle emitters depends on the constituents of the decontaminating formulation, but more importantly, on the type of surface tested. Except for the cement surface (which was particularly porous), at which the decontamination level ranged between approximately 44% and 89%, for all the other investigated surfaces, a decontamination efficiency ranging from 80.6% to 96.5% was achieved.

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Bordulev, Iurii, Roman Laptev, Viktor Kudiiarov, Roman Elman, Alexander Popov, Denis Kabanov, Ivan Ushakov, and Andrey Lider. "Positron Annihilation Spectroscopy Complex for Structural Defect Analysis in Metal–Hydrogen Systems." Materials 15, no. 5 (February 28, 2022): 1823. http://dx.doi.org/10.3390/ma15051823.

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The current work is devoted to developing a system for the complex research of metal–hydrogen systems, including in an in situ mode. The system consists of a controlled gas reactor with a unique reaction chamber, a radioisotope positron source, and a positron annihilation spectroscopy complex. The use of the system enables in situ investigation of the defect structure of solids in hydrogen sorption–desorption processes at temperatures up to 900 °C and pressures up to 50 bar. Experimental investigations of magnesium and magnesium hydride during thermal annealing were carried out to approve the possibilities of the developed complex. It was shown that one cycle of magnesium hydrogenation–dehydrogenation resulted in the accumulation of irreversible hydrogen-induced defects. The defect structure investigation of the magnesium–hydrogen system by positron annihilation techniques was supplemented with a comprehensive study by scanning electron microscopy, X-ray diffraction analysis, and hydrogen sorption–desorption studies.

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Söğüt, Ö., Ç. Dönük, G. Apaydın, and Ö. F. Bakkaloğlu. "Examination of CoNiCu thin films by using XRF and XRD." Canadian Journal of Physics 92, no. 5 (May 2014): 435–39. http://dx.doi.org/10.1139/cjp-2012-0538.

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A series of thin films of CoNiCu and NiCu produced using the electrodeposition method have been examined using X-ray fluorescence (XRF), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Energy dispersive XRF spectroscopy was used to determine the concentrations of the atomic percentage in these films. CoNiCu and NiCu thin film samples were excited by gamma rays with 59.5 keV energy photons from 100 mCi 241Am radioisotope source. K X-rays emitted by samples were counted by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. Structural analyses of these films have been done using the XRD technique and thin films were found to have a face-centred cubic (fcc) structure. In addition, surface morphologies of the films have been analysed by SEM. If one examines the SEM images of thin film samples, it can be seen that these elements have been homogeneously distributed in the samples of the thin films.

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Kobylyansky, V. N. "Optimization of assessment of the function of the main protective mechanisms of the respiratory system based on the use of albumin aerosol." Izmeritel`naya Tekhnika, no. 10 (November 17, 2023): 70–74. http://dx.doi.org/10.32446/0368-1025it.2023-10-70-74.

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The most informative, direct and non-invasive method for studying the basic protective mechanisms of the respiratory organs, the processes of deposition of inhaled substances and the clearance of them from the lungs is radioaerosol. It involves the inhalation of a diagnostic drug labeled with a radioisotope or a radioactive drug, based on the dynamics of distribution and excretion of which the indicated processes are judged. These processes and the accuracy of their assessment depend on the aerodynamic properties of the inhalant. In order to optimize the measurement of the parameters of the aerodynamic properties of a diagnostic aerosol and the function of the main protective mechanisms of the respiratory organs, a comparative analysis of different measurement methods and dispersion systems of albumin, chosen by us as the most physiological material, was performed. It has been established that the most informative and economically feasible method for assessing the aerodynamic properties of an inhalant is scanning electron microscopy. A comparative assessment of albumin macroaggregates produced by foreign representatives and albumin microspheres produced using the technology of domestic researchers, carried out using scanning electron microscopy, indicates that domestic albumin microspheres have optimal aerodynamic parameters for studying lung deposition and clearance. However, to make a final judgment about the possibilities of using these albumin microspheres, a direct assessment of their deposition in the lungs is necessary.

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Sagar, Chithajalu Kiran, Amrita Priyadarshini, Amit Kumar Gupta, and Devanshi Mathur. "Experimental investigation of tool wear characteristics and analytical prediction of tool life using a modified tool wear rate model while machining 90 tungsten heavy alloys." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 235, no. 1-2 (July 2, 2020): 242–54. http://dx.doi.org/10.1177/0954405420933113.

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Tungsten heavy alloys are widely used in the manufacturing of weights for aircraft, missiles, boats and race cars; penetrators; radiation shielding; and radioisotope containers. Manufacturing these components needs machining as a secondary operation. Since tungsten heavy alloys are difficult to machine, the in-depth analysis of tool wear growth and mechanism during machining of these alloys becomes essential. Hence, this work focuses on the experimental study of flank wear growth and its effect on other machining outputs for two different tool geometries (−5° and 2° rake angles) during turning of 90 tungsten heavy alloys. The predominant wear mechanism was identified as adhesion based on scanning electron microscopic analysis. Finally, three commonly used analytical tool wear rate models and one newly proposed model (modified Zhao model) were utilized for the prediction of flank wear growth and tool life. It was observed that the modified Zhao model could predict tool flank wear fairly well within error percentage of 4%–7% and thus could be used as a benchmark while machining difficult-to-cut alloys.

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Kozlov, Yu A., S. S. Poloyan, L. V. Bregel, V. S. Cheremnov, and N. A. Narkevich. "Laparoscopic treatment of vasorenal hydronephrosis in children using aberrant renal vessel transposition." Russian Journal of Pediatric Surgery 26, no. 3 (July 16, 2022): 135–41. http://dx.doi.org/10.55308/1560-9510-2022-26-3-135-141.

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The purpose of this article is to assess the immediate results of laparoscopic transposition of aberrant renal vessels as an effective alternative to pyeloplasty in the treatment of children with external obstruction of the pyeloureteral junction. Material and methods. The laparoscopic vascular transposition technique was used in 3 children with hydronephrosis caused by aberrant renal vessels. The preoperative diagnostic examination included: ultrasound / Doppler scanning, radioisotope renal scanning and contrast computed urography. Renoscintigraphy showed that all patients had intermittent hydronephrosis (24–36 mm) and an obstructive pattern. In order to select patients in whom vascular transposition is possible, the diuretic loading test was made at the beginning of the surgery. During the surgery, accessory renal vessels were mobilized and moved upward, where they were fixed by "wrapping" with renal pelvis tissue. Results. The median operative time was 59.0±10.2 minutes, and the median hospital stay was 3.6±0.5 days. There were no complications at the early observation period. At the follow-up (6.0–24.0 months), all patients showed a decrease in the degree of hydronephrosis and an improvement in excretory function at the renogram. Conclusion. Preliminary results of the study have demonstrated safety and efficacy of laparoscopic repositioning of aberrant renal vessels for the treatment of hydronephrosis. A careful selection of patients through intraoperative functional tests is an important step to confirm indications for this procedure and to maintain its high success rate. Any concerns about the presence of additional internal stenosis of the pyeloureteral junction, of course, should transform this surgical intervention into the classic pyeloplasty.

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He, Yupu, Xia Xiang, Lijie Sun, Chengxiang Tian, Guixia Yang, and Xiaotao Zu. "Effect of γ-irradiation on adsorption and photocatalytic ability of MoS2 nanomaterials." International Journal of Modern Physics B 33, no. 24 (September 30, 2019): 1950275. http://dx.doi.org/10.1142/s0217979219502758.

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The ability of MoS2 nanomaterials as adsorbent and photocatalytic materials of methylene blue (MB) dye after [Formula: see text]-ray irradiation is investigated. The MoS2 nanomaterials are prepared by a simple hydrothermal route, and then irradiated with Co-60 gamma radioisotope at different doses of 1, 10, 100, 1000 kGy. All the samples are characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Diffusivity Reflectance Spectroscopy (DRS) and Brunauer–Emmet–Teller (BET). The XRD analysis shows no change in crystal structure of MoS2 nanomaterials after irradiation. The DRS analysis indicates the optical bandgap increases from 1.73 to 1.82, 1.86, 1.94 and 2.00 eV, respectively. The performance of the dye-absorbing solutions and the photocatalytic dye solutions before and after irradiation is compared. After [Formula: see text]-ray irradiation, the adsorption capacity of the MoS2 nanomaterials degrades, which can be attributed to the decreased specific surface area, from 77.060 to 48.812, 35.855, 38.789 and 27.137 m2/g, respectively. The photocatalytic degradation ability for the MB solution also decreases due to the increase of optical bandgap of the samples after [Formula: see text]-ray irradiation.

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Maclin, Joshua Marvin Anthony, Tao Wang, and Shifu Xiao. "Biomarkers for the diagnosis of Alzheimer’s disease, dementia Lewy body, frontotemporal dementia and vascular dementia." General Psychiatry 32, no. 1 (February 2019): e100054. http://dx.doi.org/10.1136/gpsych-2019-100054.

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BackgroundDementia is a chronic brain disorder classified by four distinct diseases that impact cognition and mental degeneration. Each subgroup exhibits similar brain deficiencies and mutations. This review will focus on four dementia subgroups: Alzheimer’s disease, vascular dementia, frontotemporal dementia and dementia Lewy body.AimThe aim of this systematic review is to create a concise overview of unique similarities within dementia used to locate and identify new biomarker methods in diagnosing dementia.Methods123 300 articles published after 2010 were identified from PubMed, JSTOR, WorldCat Online Computer Library and PALNI (Private Academic Library Network of Indiana) using the following search items (in title or abstract): ‘Neurodegenerative Diseases’ OR ‘Biomarkers’ OR ‘Alzheimer’s Disease’ OR ‘Frontal Temporal Lobe Dementia’ OR ‘Vascular Dementia’ OR ‘Dementia Lewy Body’ OR ‘Cerebral Spinal Fluid’ OR ‘Mental Cognitive Impairment’. 47 studies were included in the qualitative synthesis.ResultsEvidence suggested neuroimaging with amyloid positron emission tomography (PET) scanning and newly found PET tracers to be more effective in diagnosing Alzheimer’s and amnesiac mental cognitive impairment than carbon-11 Pittsburgh compound-B radioisotope tracer. Newly created methods to make PET scans more accurate and practical in clinical settings signify a major shift in diagnosing dementia and neurodegenerative diseases.ConclusionVast improvements in neuroimaging techniques have led to newly discovered biomarkers and diagnostics. Neuroimaging with amyloid PET scanning surpasses what had been considered the dominant method of neuroimaging and MRI. Newly created methods to make PET scans more accurate and practical in clinical settings signify a major shift in diagnosing dementia pathology. Continued research and studies must be conducted to improve current findings and streamline methods to further subcategorise neurodegenerative disorders and diagnosis.

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WALMSLEY, J. P. "A case of atlanto-occipital arthropathy following guttural pouch mycosis in a horse. The use of radioisotope bone scanning as an aid to diagnosis." Equine Veterinary Journal 20, no. 3 (May 1988): 219–20. http://dx.doi.org/10.1111/j.2042-3306.1988.tb01504.x.

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Joseph, J., K. Lim, and J. Ramsden. "Investigation prior to thyroglossal duct cyst excision." Annals of The Royal College of Surgeons of England 94, no. 3 (April 2012): 181–84. http://dx.doi.org/10.1308/003588412x13171221589892.

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INTRODUCTION Investigation of the anterior midiine neck lump has been debated over the years with little agreement on best practice. Thyrogiossai duct cysts (TDCs) are the most common aetiology. A TDC may contain ectopic thyroid tissue, which may affect the decision to excise. METHODS A computerised survey was sent to a representative sample of UK-based ENT surgeons to determine current practice in investigation of presumed TDCs and the incidence of ectopic thyroid tissue. RESULTS Overall, 95% of those surveyed use ultrasonography, with 32% also arranging thyroid function tests. Fifteen per cent had encountered absent normal thyroid tissue in the presence of a midiine neck swelling. In 64% of cases this represented the only functioning thyroid tissue. Thyroid function tests were normal in all but two cases. CONCLUSIONS The results show a significant change in practice over the last decade. All surgeons would arrange some form of investigation of a presumed TDC, with the vast majority using ultrasonography. Radioisotope scanning should only be used if the ultrasonography or thyroid function tests are abnormal. The incidence of ectopic thyroid tissue in this survey was higher than previously calculated, with a 0.17% prevalence of midiine neck lumps representing the only functioning thyroid tissue.

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Rosenqvist, Marie. "Acetyl Group Distribution in Acetylated Wood Investigated by Microautoradiography." Holzforschung 55, no. 3 (April 25, 2001): 270–75. http://dx.doi.org/10.1515/hf.2001.045.

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Summary Sapwood of Scots pine (Pinus silvestris L.) was acetylated with 14C- and 3H-labelled acetic anhydride. The distribution of acetyl groups was investigated with microautoradiography and microautoradiographs were evaluated with ESEM, Environmental Scanning Electron Microscopy. The investigation showed that the impregnation of wood with radioisotope-labelled substances provides a good opportunity to investigate the location of substances covalently bonded to the wood material. Introduced 14C-labelled acetyl groups show an even distribution in the wood cell wall, with no discernible concentration gradients at acetylation levels of about 5, 15 and 20% weight gain. 3H-labelled acetyl groups show an even distribution in the wood cell wall at 15 and 20% weight gain, with no discernible concentration gradients. At the 5% weight gain level, however, an uneven distribution of 3H-labelled acetyl groups over the cell wall is observed. Nevertheless, the unevenness is random and no concentration gradient is discernible at this level. 3H with a relatively high resolution, 0.5–1 μm, compared to 14C with a resolution of 2–5 μm, gives more accurate information about where exactly the acetyl groups are situated in the wood cell wall. Acetic anhydride was evenly distributed when a full impregnation procedure was used. The chemical and physical properties of acetic anhydride allow a uniform penetration into the pine cell wall and a complete acetylation takes place when the specimens are heated.

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Belov, S. D., V. S. Bormashov, A. P. Volkov, and S. G. Buga. "An Electron-Beam-Induced Current Detector for Diagnostics of Power Converters of Radioisotope β Radiation Based on Diamond Schottky Barrier Diodes in a Scanning Electron Microscope." Instruments and Experimental Techniques 61, no. 6 (November 2018): 862–68. http://dx.doi.org/10.1134/s0020441218060027.

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Lee, Chang Ryong, Gun Gyun Kim, Sung Bum Park, and Sang Wook Kim. "Synthesis of Hyaluronic Acid-Conjugated Fe3O4@CeO2 Composite Nanoparticles for a Target-Oriented Multifunctional Drug Delivery System." Micromachines 12, no. 9 (August 26, 2021): 1018. http://dx.doi.org/10.3390/mi12091018.

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This study is based on the principle that superparamagnetic iron oxide nanoparticles (Fe3O4) can be used to target a specific area given that their magnetic properties emerge when an external magnetic field is applied. Cerium oxide (CeO2), which causes oxidative stress by generating reactive oxygen species (ROS) in the environment of tumor cells, was synthesized on the surface of superparamagnetic iron oxide nanoparticles to produce nanoparticles that selectively kill cancer cells. In addition, hyaluronic acid (HA) was coated on the cerium’s surface to target CD44-overexpressing tumor cells, and natZr was chelated on the Fe3O4@CeO2 surface to show the usefulness of labeling the radioisotope 89Zr (T1/2 = 3.3 d). The synthesis of Fe3O4@CeO2 was confirmed by Fourier Transform-Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD) and Field Emission-Transmission Electron Microscope (FE-TEM). The coating of HA was confirmed by FT-IR, X-ray Photoelectron. Spectroscopy (XPS), FE-TEM, Energy-Dispersive X-ray Spectroscopy (EDS) and Thermogravimetric Analysis (TGA)/Differential Scanning Calorimetry (DSC). The sizes of the prepared nanoparticles were confirmed through FE-TEM and Field Emission-Scanning Electron (FE-SEM) (sizes of 15 to 30 nm), and it was confirmed that natZr was introduced onto the surface of the nanoparticles using EDS. The particle size of the dispersed material was limited through Dynamic Light Scattering (DLS) to about 148 nm in aqueous solution, which was suitable for the (enhanced permeation and retention) EPR effect. It was confirmed that the HA-coated nanoparticles have good dispersibility. Finally, a cytotoxicity evaluation confirmed the ability of CeO2 to generate ROS and target the delivery of HA. In conclusion, Fe3O4@CeO2 can effectively inhibit cancer cells through the activity of cerium oxide in the body when synthesized in nano-sized superparamagnetic coral iron that has magnetic properties. Subsequently, by labeling the radioactive isotope 89Zr, it is possible to create a theranostic drug delivery system that can be used for cancer diagnosis.

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Fang, Ting-zheng, Jia-rui Zhu, Ling Chuan, Wen-rui Zhao, Ying-kui Liang, and Sheng Wang. "Differential diagnosis of Warthin’s tumor complicated with lung adenocarcinoma by 18F- FDG PET/CT imaging and radioisotope scanning with Tc-99m pertechnetate: A case report and literature review." Chinese Journal of Cancer Research 22, no. 2 (June 2010): 163–66. http://dx.doi.org/10.1007/s11670-010-0163-z.

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Gill, James, Daniel Brimm, Peter McMeniman, Timothy McMeniman, and Peter Myers. "LONG-TERM RESULTS OF PER-OPERATIVE KNEE ARTHROSCOPY IN CONFIRMING SUITABILITY FOR UNICOMPARTMENTAL KNEE ARTHROPASTY." Orthopaedic Proceedings 105-B, SUPP_13 (August 7, 2023): 57. http://dx.doi.org/10.1302/1358-992x.2023.13.057.

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AbstractIntroductionPatient selection is key to the success of medial unicondylar knee arthroplasty (UKA). Progression of arthritis is the most common indication for revision. Various methods of assessing the lateral compartment have been used including stress radiography, radioisotope bone scanning, MRI, and visualisation at the time of surgery. Arthroscopy is another means of assessing the integrity of the lateral compartment.MethodsWe used per-operative arthroscopy as a means to confirm suitability for UKA in a consecutive series of 279 Oxford medial UKA. This study reports the long-term results of a previously published cohort of knees. Our series of UKA with per-operative arthroscopy (Group 1) was compared to all Oxford UKA (Group 2) and all UKA in the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) (Group 3).ResultsThe 14-year cumulative percentage revision (CPR) was 18.5% (95% CI 12.7, 26.4) for group 1, 19.7% (95% CI 18.8, 20.6) for group 2, and 19.2% (95% CI 18.5, 19.8) for group 3. There was no statistically significant difference in the (CPR) for the entire period when group 1 was compared to groups 2 or 3. Progression of arthritis was the indication for revision in similar proportions for the three groups (Group 1: 32.3%, Group 2: 35.7% and Group 3: 33.5%). Following per-operative arthroscopy 21.6% (77/356) of knees underwent a change of surgical plan from UKA to TKA.ConclusionPer-operative arthroscopy may improve medium-term medial unicompartmental knee survivorship but does not improve long-term survivorship nor reduce revision due to progression of arthritis.

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Tsuyuguchi, Naohiro, Ichiro Sunada, Yoshiyasu Iwai, Kazuhiro Yamanaka, Kiyoaki Tanaka, Toshihiro Takami, Yumiko Otsuka, et al. "Methionine positron emission tomography of recurrent metastatic brain tumor and radiation necrosis after stereotactic radiosurgery: is a differential diagnosis possible?" Journal of Neurosurgery 98, no. 5 (May 2003): 1056–64. http://dx.doi.org/10.3171/jns.2003.98.5.1056.

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Object. In this study the authors examined how to differentiate radiation necrosis from recurrent metastatic brain tumor following stereotactic radiosurgery by using positron emission tomography (PET) with l-[methyl-11C]methionine (MET). Methods. In 21 adult patients with suspected recurrent metastatic brain tumor or radiation injury, MET-PET scans were obtained. These patients had previously undergone stereotactic radiosurgery and subsequent contrast-enhanced magnetic resonance (MR) examinations before nuclear medicine imaging. Positron emission tomography images were obtained as a static scan of 10 minutes performed 20 minutes after injection of 370 MBq of MET. On MET-PET scans, the portion of the tumor with the highest accumulation of MET was selected as the region of interest (ROI), and the ratio of tumor tissue to normal tissue (T/N) was defined as the mean counts of radioisotope per pixel in the tumor divided by the mean counts per pixel in normal gray matter. The standardized uptake value (SUV) was calculated using the same ROI in the tumor. The accuracy of the MET-PET scan was evaluated by correlating findings with results of subsequent histological analysis (11 cases) or, in cases in which surgery or biopsy was not performed, with subsequent clinical course and MR imaging findings (10 cases). Histological examinations performed in 11 cases showed viable tumor cells with necrosis in nine and necrosis with no viable tumor cells in two. Another 10 cases were characterized as radiation necrosis because the patients exhibited stable neurological symptoms with no sign of massive enlargement of the lesion on follow-up MR images after 5 months. The mean T/N was 1.15 in the radiation necrosis group (12 cases) and 1.62 in the tumor recurrence group (nine cases). The mean SUV was 1.78 in the necrosis group and 2.5 in the recurrence group. There were statistically significant differences between the recurrence and necrosis groups in T/N and SUV. Furthermore, the borderline T/N value was 1.42 according to a 2 × 2 factorial table (high T/N or low T/N, recurrence or necrosis). From this result, the sensitivity and specificity of MET-PET scanning in detecting tumor recurrence were determined to be 77.8 and 100%, respectively. Conclusions. The use of MET-PET scanning is a sensitive and accurate technique for differentiating between metastatic brain tumor recurrence and radiation necrosis following stereotactic radiosurgery. This study reveals important information for creating strategies to treat postradiation reactions.

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Mirzayev, Matlab, Ertugrul Demir, Khagani Mammadov, Ravan Mehdiyeva, Sakin Jabarov, A. Beril Tugrul, Sapina Biira, Nguyen Tiep, and Thabsile Thabethe. "Thermodynamics kinetics of boron carbide under gamma irradiation dose." International Journal of Modern Physics B 33, no. 09 (April 10, 2019): 1950073. http://dx.doi.org/10.1142/s0217979219500735.

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In this paper, high purity boron carbide samples were irradiated by [Formula: see text]Co gamma radioisotope source (0.27 Gy/s dose rate) with 50, 100, 150 and 200 irradiation hours at room-temperature. The unirradiated and irradiated boron carbide samples were heated from 30[Formula: see text]C to 1000[Formula: see text]C at a heating rate of 5[Formula: see text]C/min under the argon gas atmosphere of flow rate 20 ml/min. Thermogravimetric (TG) and Differential Scanning Calorimetry (DSC) were carried out in order to understand the thermodynamic kinetics of boron carbide samples. The weight kinetics, activation energy and specific heat capacity of the unirradiated and irradiated boron carbide samples were examined in two parts, T [Formula: see text] 650[Formula: see text]C and T [Formula: see text] 650[Formula: see text]C, according to the temperature. The dynamic of quantitative changes in both ranges is different depending on the irradiation time. While the phase transition of unirradiated boron carbide samples occurs at 902[Formula: see text]C, this value shifts upto 940[Formula: see text]C in irradiated samples depending on the irradiation time. The activation energy of the unirradiated boron carbide samples decreased from 214 to 46 J/mol in the result of 200[Formula: see text]h gamma irradiation. The reduction of the activation energy after the irradiation compared to the initial state shows that the dielectric properties of the irradiated boron carbide samples have been improved. After the gamma irradiation, two energy barrier states depending on the absorption dose of samples were formed in the irradiated samples. The first and second energy barriers occurred in 0.56–0.80 and 0.23–0.36 eV energy intervals, respectively. The existence of two energy levels in the irradiated boron carbide indicates that the point defects are at deep levels, close to the valence band.

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Patt, Y. Z., L. M. Lamki, T. P. Haynie, M. W. Unger, M. G. Rosenblum, A. Shirkhoda, and J. L. Murray. "Improved tumor localization with increasing dose of indium-111-labeled anti-carcinoembryonic antigen monoclonal antibody ZCE-025 in metastatic colorectal cancer." Journal of Clinical Oncology 6, no. 8 (August 1988): 1220–30. http://dx.doi.org/10.1200/jco.1988.6.8.1220.

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Monoclonal antibodies (MoAbs) against carcinoembryonic antigen (CEA) react with human colorectal cancer cells, and when labeled with a gamma-emitting radioisotope, may help to localize known and occult metastatic disease. We tested ZCE-025 (Hybritech, Inc, San Diego), a high-affinity immune gamma globulin1 (IgG1) MoAb anti-CEA that does not react with normal granulocyte glycoproteins in a phase I/II trial to determine the reagent's toxicity and its maximum efficacy in detecting metastatic colorectal cancer. Increasing doses of unlabeled ZCE-025 were mixed with 1 mg of Indium-111 (111In)-radiolabeled MoAb and administered intravenously (IV) to 34 patients who had metastatic colorectal cancer. Planar nuclear or single photon emission computed tomographic (SPECT) scans were performed 48 to 72 and 120 to 144 hours later. Total dose of MoAb and scanning sensitivity (number of imaged lesions/number of known lesions) were correlated up to 80 mg. At doses of 2.5 to 20 mg, a mean of 22% of the lesions were imaged; at 40 mg, 77% were imaged (P less than .01). Liver metastases were detected as areas of increased activity ("hot") at the 40 mg dose but showed decreased MoAb uptake at lower doses. At the 40 mg dose normal liver parenchymal uptake of the labeled MoAb was lower with respect to blood pool compared with the other doses. At 80 mg, however, sensitivity of detection declined to 21%. One milligram of 111In-labeled ZCE-025 antibody coinfused with 39 mg of unlabeled antibody appeared optimal for detecting metastatic colorectal cancer, particularly in the liver. Although the exact mechanism(s) for this dose effect is currently unknown, a partial "blocking" effect of unlabeled antibody with a change in MoAb biodistribution may be occurring.

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Ma, Jun, Yawen Yang, Linhao Sun, and Tingting Wu. "Effects of sufentanil in combination with dexmedetomidine for patient-controlled intravenous analgesia after renal transplantation." Vojnosanitetski pregled, no. 00 (2024): 57. http://dx.doi.org/10.2298/vsp231103057m.

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Background/Aim. Nowadays, the most convenient analgesic method is patient-controlled intravenous injection of one or more adjuvant drugs. The aim of our study was to evaluate the effects of sufentanil plus dexmedetomidine for patient-controlled intravenous analgesia (PCIA) after renal transplantation. Methods. Seventy-eight patients receiving living-related renal transplantation under general anesthesia were selected. Radioisotope scanning was performed, and the single glomerular filtration rate of the unilateral kidney was ? 40 mL/min/1.73 m2. The control group (CG) and observation group (OG) (39 patients in each group) were analgesic with sufentanil and sufentanil plus dexmedetomidine, respectively. When the Visual Analogue Scale (VAS) score exceeded 4 points, 0.05 mg/kg oxycodone was intravenously injected for remedial analgesia. Plasma levels of endothelin, urea nitrogen, and creatinine were measured by radioimmunoassay. Heart rate (HR), mean arterial pressure, oxygen saturation, VAS score, and sedation score were recorded before anesthesia and after surgery. Analgesic remediation rate, number of effectively pressing the PCIA pump, and incidence rate of adverse reactions within 48 hrs after surgery were recorded. Results. HR of OG was significantly lower than that of CG 6 and 12 hrs after surgery (p < 0.05). VAS score of OG was lower than that of CG 6, 12, and 24 hrs after surgery (p < 0.05). OG had a lower postoperative remedial rate, number of effectively pressing the PCIA pump, and incidence rates of nausea and vomiting (p < 0.05) compared to CG. Endothelin, urea nitrogen, and creatinine levels significantly decreased after surgery compared with those before anesthesia (p < 0.05). The levels of OG were lower than those of CG at each time point after surgery (p < 0.05). Conclusion. Sufentanil plus dexmedetomidine can be safely and effectively used for PCIA after renal transplantation, with superior outcomes to those of sufentanil alone.

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Schwartz, Richard B., B. Leonard Holman, Joseph F. Polak, Basem M. Garada, Marc S. Schwartz, Rebecca Folkerth, Paulo A. Carvalho, et al. "Dual-isotope single-photon emission computerized tomography scanning in patients with glioblastoma multiforme: association with patient survival and histopathological characteristics of tumor after high-dose radiotherapy." Journal of Neurosurgery 89, no. 1 (July 1998): 60–68. http://dx.doi.org/10.3171/jns.1998.89.1.0060.

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Object. The study was conducted to determine the association between dual-isotope single-photon emission computerized tomography (SPECT) scanning and histopathological findings of tumor recurrence and survival in patients treated with high-dose radiotherapy for glioblastoma multiforme. Methods. Studies in which SPECT with 201Tl and 99mTc-hexamethypropyleneamine oxime (HMPAO) were used were performed 1 day before reoperation in 47 patients with glioblastoma multiforme who had previously been treated by surgery and high-dose radiotherapy. Maximum uptake of 201Tl in the lesion was expressed as a ratio to that in the contralateral scalp, and uptake of 99mTc-HMPAO was expressed as a ratio to that in the cerebellar cortex. Patients were stratified into groups based on the maximum radioisotope uptake values in their tumor beds. The significance of differences in patient gender, histological characteristics of tissue at reoperation, and SPECT uptake group with respect to 1-year survival was elucidated by using the chi-square statistic. Comparisons of patient ages and time to tumor recurrence as functions of 1-year survival were made using the t-test. Survival data at 1 year were presented according to the Kaplan—Meier method, and the significance of potential differences was evaluated using the log-rank method. The effects of different variables (tumor type, time to recurrence, and SPECT grouping) on long-term survival were evaluated using Cox proportional models that controlled for age and gender. All patients in Group I (201Tl ratio < 2 and 99mTc-HMPAO ratio < 0.5) showed radiation changes in their biopsy specimens: they had an 83.3% 1-year survival rate. Group II patients (201T1 ratio < 2 and 99mTc-HMPAO ratio of ≥ 0.5 or 201Tl ratio between 2 and 3.5 regardless of 99mTc-HMPAO ratio) had predominantly infiltrating tumor (66.6%); they had a 29.2% 1-year survival rate. Almost all of the patients in Group III (201Tl ratio > 3.5 and 99mTc-HMPAO ratio ≥ 0.5) had solid tumor (88.2%) and they had a 6.7% 1-year survival rate. Histological data were associated with 1-year survival (p < 0.01); however, SPECT grouping was more closely associated with 1-year survival (p < 0.001) and was the only variable significantly associated with long-term survival (p < 0.005). Conclusions. Dual-isotope SPECT data correlate with histopathological findings made at reoperation and with survival in patients with malignant gliomas after surgical and high-dose radiation therapy.

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Hollett, Peter D., and Ehud Ur. "Applications of radioisotopic scanning in neuroendocrinology." Current Opinion in Endocrinology and Diabetes 2, no. 2 (April 1995): 134–39. http://dx.doi.org/10.1097/00060793-199504000-00010.

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Makarova, T. P., N. V. Samoilova, Yu S. Melnikova, L. V. Poladova, N. V. Akhmedgareeva, and Sh K. Takhautdinov. "Vesicoureteral reflux as a manifestation of CAKUT-syndrome in children: the problem of late diagnosis." Nephrology (Saint-Petersburg) 25, no. 3 (April 23, 2021): 84–90. http://dx.doi.org/10.36485/1561-6274-2021-25-3-84-90.

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CAKUT-syndrome includes combined congenital abnormalities of the kidneys and urinary tract and is a complex problem in pediatrics, requiring an interdisciplinary approach of doctors of various specialties. One of the most severe manifestations of CAKUT-syndrome is vesicoureteral reflux, which is often the main manifestation of a congenital abnormality of the kidneys and urinary tract. Structural and urodynamic disorders in the organs of the urinary system in vesicoureteral reflux can lead to the formation of reflux nephropathy and chronic kidney disease. Low-symptom clinical manifestations of reflux nephropathy make it difficult to diagnose it early. Vesicoureteral reflux leads to intrarenal reflux, repeated attacks of pyelonephritis and sclerosis of the renal tissue, which in 25-60 % of cases causes end-stage chronic renal failure due to vesicoureteral reflux. Given the absence of specific pathognomonic clinical manifestations of reflux nephropathy, laboratory indicators are of fundamental importance in the diagnosis-levels of albuminuria, leukocyturia, urinary sediment fermenturia, urine osmolarity, daily urinary excretion of β2 – microglobulin and a wide arsenal of methods for diagnosing reflux nephropathy and scarring of the renal parenchyma: ultrasound with dopplerography of the renal blood flow, magnetic resonance imaging and computed tomography, radioisotope scanning. The imperfection of instrumental methods for visualizing the initial stages of kidney fibrosis dictates the need to develop alternative, more sensitive methods for early diagnosis of reflux nephropathy. One of the directions of this search is molecular diagnostics, which allows you to detect possible damage to the renal tissue at the subcellular level long before the clinical manifestations of pathology, personify nephroprotective therapy and prevention of reflux nephropathy. The article presents clinical observations from our own practice of late diagnosis of reflux nephropathy, in which renal pathology was first detected at stages 5 and 3 of chronic kidney disease in two boys aged 10 and 16 years, respectively, who were on inpatient treatment in the Nephrology Department of the Children's Republican clinical hospital.

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Bal, Chandresakhar, Sanjana Ballal, Kumar Kallur, Anna Karmann, Ye Yuan, Jessica Rearden, Kathryn Shah, et al. "Abstract 2585: First in human study with a novel peptide binder to glypican-3, demonstrates high specificity as a PET imaging agent in patients with hepatocellular carcinoma." Cancer Research 84, no. 6_Supplement (March 22, 2024): 2585. http://dx.doi.org/10.1158/1538-7445.am2024-2585.

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Abstract Introduction: Hepatocellular carcinoma (HCC) is the most common primary liver malignancy. The American Association for the Study of Liver Disease recommends surveillance for high-risk individuals with abdominal ultrasound, triple phase contrast CT or MRI. However, these imaging techniques have limited sensitivity in classifying lesions smaller than 2 centimeters. The use of [18F]FDG Positron Emission Tomography (PET) is constrained due to insufficient uptake by HCC lesions over background liver uptake. Hence, there is an urgent need for more precise radiotracers for HCC. This study introduces the development of a novel radiotracer that binds to glypican-3 (GPC3), a cell membrane-anchored oncofetal protein overexpressed in HCC with minimal normal tissue expression. Methods: [68Ga]Ga-RYZ-GPC3 is composed of a small macrocyclic peptide binder with high affinity to GPC3 linked with a tetraxetan moiety capable of chelating a variety of radioisotopes including positron-emitting 68Ga and other radiometals. The unlabeled binder to GPC3 was synthesized by the sponsor and provided to three imaging centers in India as part of investigator-initiated trials reviewed and approved by each site’s institutional review board and ethics committee. Labeling with 68Ga and quality checks of the product was performed locally at each center. Patients with high clinical suspicion or with confirmed HCC who gave informed consent received injections of 1.5-5.5 mCi of [68Ga]Ga-RYZ-GPC3 and underwent PET-CT scanning at predetermined intervals. Some patients underwent companion [18F]FDG PET-CT scans in accordance with local guidelines. Results: A total of 64 patients underwent [68Ga]Ga-RYZ-GPC3 PET-CT scans. The median age within the cohort was 61 (41-83), 22% were female. Liver cirrhosis was present in 72% of patients, attributed to hepatitis B, hepatitis C or NASH in 17%, 13% and 20% of cases. Notably, 92% of patients exhibited at least one positive lesion on [68Ga]Ga-RYZ-GPC3 scans. The median SUVmax of GPC3-avid liver lesions was 15.5 (range 1.1 to 137.0) while the median liver SUVmean was 1.6 (0.3-7.9). Physiologic uptake was predominantly observed in the kidneys, the primary route of clearance, with a median SUVmean of 10.9 (2.2-20.7). Additionally, 20 patients underwent [18F]FDG PET-CT scan for comparison. The median SUVmax of lesions on 68Ga-RYZ-GPC3 vs [18F]FDG PET was 11.0 (1.1-137.0) vs 3.8 (1.2-12.2). Conclusion: Early human imaging results in patients with HCC indicate that [68Ga]Ga-RYZ-GPC3 has high tumor lesion specificity compared to normal liverand demonstrates the potential of [68Ga]Ga-RYZ-GPC3 to improve detection of HCC over conventional [18F]FDG PET-CT. In addition, the binder could be complexed with a therapeutic radioisotope as a novel targeted therapeutic option for HCC. Further investigation of this first-in-class binder to HCC is warranted. Citation Format: Chandresakhar Bal, Sanjana Ballal, Kumar Kallur, Anna Karmann, Ye Yuan, Jessica Rearden, Kathryn Shah, Charlotte Lorenz, Susan Moran, Ken Song, Ishita Sen. First in human study with a novel peptide binder to glypican-3, demonstrates high specificity as a PET imaging agent in patients with hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2585.

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Konrády, András. "Differentiated thyroid cancer – 2009." Orvosi Hetilap 152, no. 5 (January 2011): 163–70. http://dx.doi.org/10.1556/oh.2011.29028.

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Three years ago continental guidelines were published referring management and follow-up of low risk thyroid cancer patients. The aim of this paper is to summarize the changes and new directions in this field. High risk patients require another protocol. Neck ultrasound plays important role in differential diagnosis and in detecting recurrences. Some new ultrasound techniques are discussed, too. FDG-PET can help to solve the problem of patients having negative scan and increased thyroglobulin level. In recent years there was an expansion of our knowledge about the pathomechanism of thyroid cancer. It appears that genetic alterations frequently play a key role in carcinogenesis. There are molecular methods that allow the detection of these genetic events in thyroid fine needle aspirations samples providing important information for diagnosis, management and prognosis. Instead of diagnostic whole body scanning the posttherapeutic scan became preferable but in high risk cases the diagnostic whole body scintigrams serve useful data. Primary therapy of thyroid cancer is an adequate surgery: total thyreoidectomy and, if necessary, lymph node dissection or limited surgery in selected cases. Nowadays radioguided surgery can help to improve the results. Radioiodine therapy (e.g. rest ablation) proved to be a safe and effective method to complete surgery. It can prevent relapses and results in longer survival. Thyroid hormone withdrawal or recombinant human thyrotropin stimulation can increase thyrotropin level before radioiodine treatment. These two methods have similar success rate of rest ablation but irradiation burden of blood is lower in the case of exogenous stimulation which avoids hypothyroid state and preserves quality of life. Since tumor cells fail to maintain the ability to perform physiological functions they undergo dedifferentiation. Therefore, an important aim is to reactivate some function of differentiated cells, e.g. iodine uptake, production of thyroperoxydase and thyroglobulin. Opportunities for this therapeutic effort are also mentioned. Restoration of iodine uptake enables radioisotope treatment. Until now there has been little interest in the development of new drugs for the treatment of thyroid cancer. However, advances in our understanding of tumor cell biology will lead to a paradigm shift in the therapy that is likely to benefit patients who have high risk disease and who do not almost have any therapeutic option. There are new drugs in clinical trials that appear to be more effective than earlier cytotoxic agents. Probably modern chemotherapy of advanced thyroid cancer will have significant results in the near future. Orv. Hetil., 2011, 152, 163–170.

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Tugushev, A. S., O. S. Cherkovska, and D. I. Mikhantiev. "Assessment of hemodynamic parameters of hepatic and visceral blood flow in decompensated liver cirrhosis." Zaporozhye Medical Journal 23, no. 3 (June 7, 2021): 363–69. http://dx.doi.org/10.14739/2310-1210.2021.3.224265.

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The aim. To assess the hemodynamic parameters of the hepatic and visceral blood flow in patients with compensated and decompensated liver cirrhosis. Materials and methods. 290 patients with liver cirrhosis were examined: 206 had gastrointestinal bleeding, 84 had diuretic-resistant ascites. Ultrasonic scanning, Doppler sonography, esophagogastroduodenoscopy, angiography, radioisotope scintigraphy were performed to assess blood flow in the portal, splenic and superior mesenteric veins and in the hepatic, splenic and superior mesenteric arteries. Results. Change in the hepatic microcirculatory blood flow in the natural course of liver cirrhosis was characterized by decreased portal and increased arterial blood flow, “arterialization” of hepatic blood flow based on scintigraphy. Decompensation of the disease was associated with progressive reduction in both portal and arterial hepatic blood flow, which were correlated with the severity of functional liver disorders regardless of the complication nature. The portal blood flow in the natural course of liver cirrhosis was characterized by 3.5–4.5 times increased volume of visceral blood. Decompensation of the disease was accompanied by a decrease in blood flow in the portal vein as compared to the splenic and superior mesenteric veins by 1.8–2.2 and 1.5–2.7 times, respectively. Arterial blood flow in the natural course of liver cirrhosis was characterized by a relatively increased hepatic arterial flow. The ultrasound criterion of hepatic blood flow “arterialization” was an increase in hepatic-splenic arterial index, which can be used as a sign to differentiate between different forms of portal hypertension. Decompensation of the disease was characterized by an average of 8.2 % decreased arterial blood flow in the hepatic artery compared to the splenic artery in dynamics. Prognostically unfavorable signs were the progression of splenomegaly degree, the increase in the portal vein diameter with the decreased velocity characterizing the increase in congestive index by 2.4–2.6 times, the decrease in the hepatic artery diameter and velocity in it over time.Conclusions. The hepatic and visceral blood flow characteristics should be considered when choosing method of conservative, surgical or minimally invasive treatment of liver cirrhosis complications. Based on the hepatic hemodynamic characteristics, the mismatch between portal perfusion (reduced) and visceral blood flow (increased) is the essence of portal hypertension in liver cirrhosis. Accordingly, the criterion of treatment effectiveness in decompensated liver cirrhosis should be improved portal liver perfusion and (or) reduced volume of visceral blood flow.

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Ohnuma, Tohru, and Keizo Ishii. "Study of soil particles containing radioactive cesium in paddy field soil using an energy-dispersive X-ray spectroscopy and autoradiogram method." International Journal of PIXE 28, no. 01n02 (January 2018): 29–33. http://dx.doi.org/10.1142/s0129083519500050.

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The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in 2011 caused the widespread contamination of Fukushima Prefecture by radioactive cesium. The cesium radioisotopes are considered to have remained in the soil for seven years. We investigated this situation by analyzing soil from paddy fields in the area. We investigated the structure of soil particles using scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM–EDS) and autoradiogram (ARG). We estimated the percentage of clay in the soil based on its composition, and then obtained the radioactivity of the cesium radioisotopes for each soil particle size as a function of penetration. The cesium radioisotopes were exponentially distributed in soil containing a large proportion of clay. Hence, we confirmed that the quantity of clay in the soil is a very important factor with respect to the possibility of the resumption of agriculture in the restricted area.

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Journal articles on the topic 'Radioisotope scanning'

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