Journal articles: 'Radioisotopes in endocrinology'

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Brown, Aaron P., Jergin Chen, Ying J. Hitchcock, Aniko Szabo, Dennis C. Shrieve, and Jonathan D. Tward. "The Risk of Second Primary Malignancies up to Three Decades after the Treatment of Differentiated Thyroid Cancer." Journal of Clinical Endocrinology & Metabolism 93, no. 2 (February 1, 2008): 504–15. http://dx.doi.org/10.1210/jc.2007-1154.

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Abstract Background: The 10-yr survival rate of patients with differentiated thyroid cancer exceeds 90%. These patients may be at elevated risk for secondary cancers. Methods: The risk of nonthyroid second primary malignancies after differentiated thyroid cancer was determined in 30,278 patients diagnosed between 1973 and 2002 from centers participating in the National Cancer Institute’s Surveillance, Epidemiology, and End Results program. Median follow-up was 103 months (range, 2–359 months). Risk was further assessed for the addition of radioisotope therapy, gender, latency to development of secondary cancer, and age at thyroid cancer diagnosis. Results: There were 2158 patients who developed a total of 2338 nonthyroid second primary malignancies, significantly more than that expected in the general population [observed/expected (O/E) = 1.09; 95% confidence interval (CI), 1.05–1.14; P < 0.05; absolute excess risk per 10,000 person-years (AER) = 6.39]. A significantly greater risk of second primary malignancies over that expected in the general population was for patients treated with radioisotopes (O/E = 1.20; 95% CI, 1.07–1.33; AER = 11.8) as well as for unirradiated patients (O/E = 1.05; 95% CI, 1.00–1.10; AER = 3.53). However, the increased risk was greater for the irradiated vs. the unirradiated cohort (relative risk = 1.16; 95% CI, 1.05–1.27; P < 0.05). Gender did not affect risk. The greatest risk of second primary cancers occurred within 5 yr of diagnosis and was elevated for younger patients. Conclusions: The overall risk of second primary malignancies is increased for thyroid cancer survivors and varies by radioisotope therapy, latency, and age at diagnosis.

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Sakata, S., Y. Fuwa, S. Goto, M. Fukui, H. Yuasa, H. Takuno, H. Sarui, I. Matsui, T. Ogawa, and N. Sasano. "Two cases of Graves’ disease with presentation of unilateral diffuse uptake of radioisotopes." Journal of Endocrinological Investigation 16, no. 11 (December 1993): 903–7. http://dx.doi.org/10.1007/bf03348954.

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Vucina, Jurij, and Ruben Han. "Production and therapeutic application of rhenium isotopes, rhenium-186 and rhenium-188: Radioactive pharmaceuticals of the future." Medical review 56, no. 7-8 (2003): 362–65. http://dx.doi.org/10.2298/mpns0308362v.

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Introduction In contemporary nuclear medicine, alpha, pure beta or beta-gamma emitters are used for targeted therapy. Use of pure and combined alpha/beta emitters in oncology, endocrinology, rheumatology and, a short while ago, interventional cardiology, has refined as an important alternative to more common therapeutic regimens. Two radioisotopes of rhenium, rhenium-186 and rhenium-188, are of particular interest. Production of Rhenium-186 and Rhenium-188 Rhenium-186 is routinely produced in nuclear reactors by direct neutron activation of metallic rhenium enriched with 185Re via 185Re(n,)186Re nuclear reaction. For production of 188Re the target is 186W. 188W is produced by double neutron capture which gives 188Re due to beta decay. Separation of 188Re is performed in generators by column chromatography, extraction or by gel technology. The best results are obtained using chromatographic 188W/188Re generator in which 188W is adsorbed on aluminum. Rhenium-188 is eluted in saline solution. Radiopharmaceuticals labeled with rhenium radioisotopes and their clinical applications There are several fields of applications of radiopharmaceuticals labeled with 186,188Re. For bone pain palliation the most often used are 186Re-HEDP and 188Re-DMSA. For synovectomy, 186Re-sulphide in kit form is already commercially available. Endovascular radiation therapy is performed by using 188Re-perrhenate or 188Re-MAG3. Labeling of peptides and antibodies with 188Re is also reported. Application of rhenium radioisotopes depends on their specific activity. Rhenium-186,188 of low specific activity can be used only for labeling of particles or diphosphonates. However, labeling of peptides or antibodies can be performed only by using 188Re of high specific activity. Conclusion 188Re is expected to have wide applications after development of a chromatographic 188W/188Re generator. One of the advantages of rhenium is its chemical similarity with technetium. So technetium analogues labeled with 186,188Re can be developed for several specific applications.

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Santesmases, María Jesús. "Peace Propaganda and Biomedical Experimentation: Influential Uses of Radioisotopes in Endocrinology and Molecular Genetics in Spain (1947–1971)." Journal of the History of Biology 39, no. 4 (October 12, 2006): 765–94. http://dx.doi.org/10.1007/s10739-006-9112-6.

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De la Vieja, Antonio, and Pilar Santisteban. "Role of iodide metabolism in physiology and cancer." Endocrine-Related Cancer 25, no. 4 (April 2018): R225—R245. http://dx.doi.org/10.1530/erc-17-0515.

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Iodide (I−) metabolism is crucial for the synthesis of thyroid hormones (THs) in the thyroid and the subsequent action of these hormones in the organism. I−is principally transported by the sodium iodide symporter (NIS) and by the anion exchanger PENDRIN, and recent studies have demonstrated the direct participation of new transporters including anoctamin 1 (ANO1), cystic fibrosis transmembrane conductance regulator (CFTR) and sodium multivitamin transporter (SMVT). Several of these transporters have been found expressed in various tissues, implicating them in I−recycling. New research supports the exciting idea that I−participates as a protective antioxidant and can be oxidized to hypoiodite, a potent oxidant involved in the host defense against microorganisms. This was possibly the original role of I−in biological systems, before the appearance of TH in evolution. I−per se participates in its own regulation, and new evidence indicates that it may be antineoplastic, anti-proliferative and cytotoxic in human cancer. Alterations in the expression of I−transporters are associated with tumor development in a cancer-type-dependent manner and, accordingly, NIS, CFTR and ANO1 have been proposed as tumor markers. Radioactive iodide has been the mainstay adjuvant treatment for thyroid cancer for the last seven decades by virtue of its active transport by NIS. The rapid advancement of techniques that detect radioisotopes, in particular I−, has made NIS a preferred target-specific theranostic agent.

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Mueller, Bryon, and Michael K. O'Connor. "Effects of Radioisotopes on the Accuracy of Dual-Energy X-ray Absorptiometry for Bone Densitometry." Journal of Clinical Densitometry 5, no. 3 (September 2002): 283–87. http://dx.doi.org/10.1385/jcd:5:3:283.

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Livesey, G., P. D. G. Wilson, J. R. Dainty, J. C. Brown, R. M. Faulks, M. A. Roe, T. A. Newman, J. Eagles, F. A. Mellon, and R. H. Greenwood. "Simultaneous time-varying systemic appearance of oral and hepatic glucose in adults monitored with stable isotopes." American Journal of Physiology-Endocrinology and Metabolism 275, no. 4 (October 1, 1998): E717—E728. http://dx.doi.org/10.1152/ajpendo.1998.275.4.e717.

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The rates (and extent) of appearance of glucose in arterialized plasma from an oral glucose load and from liver (RaO, RaH) can be estimated in humans using radioisotopes, but estimates vary among laboratories. We investigated the use of stable isotopes and undertook 22 primed intravenous infusions ofd-[6,6-2H2]glucose with an oral load includingd-[13C6]glucose in healthy humans. The effective glucose pool volume (VS) had a lower limit of 230 ml/kg body weight (cf. 130 ml/kg commonly assumed). This VSin Steele’s one-compartment model of glucose kinetics gave a systemic appearance from a 50-g oral glucose load per 70 kg body weight of 96 ± 3% of that ingested, which compared with a theoretical value of ∼95%. Mari’s two-compartment model gave 100 ± 3%. The two models gave practically identical RaOand RaHat each point in time and a plateau in the cumulative RaOwhen absorption was complete. Less than 3% of13C was recycled to [13C3]glucose, suggesting that recycling errors were practically negligible in this study. Causes of variation among laboratories are identified. We conclude that stable isotopes provide a reliable and safe alternative to radioactive isotopes in these studies.

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Mak, Ingrid Y. F., Aimee R. Hayes, Bernard Khoo, and Ashley Grossman. "Peptide Receptor Radionuclide Therapy as a Novel Treatment for Metastatic and Invasive Phaeochromocytoma and Paraganglioma." Neuroendocrinology 109, no. 4 (2019): 287–98. http://dx.doi.org/10.1159/000499497.

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At present there is no clinical guideline or standardised protocol for the treatment of metastatic or invasive phaeochromocytoma and paraganglioma (collectively known as PPGL) due to the rarity of the disease and the lack of prospective studies or extended national databases. Prognosis is mainly determined by genetic predisposition, tumour burden, rate of disease progression, and location of metastases. For patients with progressive or symptomatic disease that is not amenable to surgery, there are various palliative treatment options available. These include localised therapies including radiotherapy, radiofrequency, or cryoablation, as well as liver-directed therapies for those patients with hepatic metastases (e.g., transarterial chemoembolisation) and systemic therapies including chemotherapy or molecular targeted therapies. There is currently intense research interest in the value of radionuclide therapy for neuroendocrine tumours, including phaeochromocytoma and paraganglioma, with either iodine-131 (131I)-radiolabelled metaiodobenzylguanidine or very recently peptide receptor radionuclide therapy (PRRT), and the most important contemporary clinical studies will be highlighted in this review. The studies to date suggest that PRRT may induce major clinical, biochemical, and radiological changes, with 177Lu-DOTATATE being most efficacious and presenting less toxicity than 90Y-DOTATATE. Newer combination therapies with combined radioisotopes, or combinations with chemotherapeutic agents, also look promising. Given the favourable efficacy, logistic, and safety profiles, we believe that PRRT will probably become the standard treatment for inoperable metastatic PPGL in the near future, but we await data from definitive randomised controlled trials to understand its role.

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Sandberg, Ann-Sofie. "The Use of Caco-2 Cells to Estimate Fe Absorption in Humans - a Critical Appraisal." International Journal for Vitamin and Nutrition Research 80, no. 45 (October 1, 2010): 307–13. http://dx.doi.org/10.1024/0300-9831/a000038.

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The Caco-2 cell model is widely used to assess the bioaccessibility/availability of iron from foods and diets. Analysis of iron uptake in this human epithelial cell line is usually preceded by a two-step digestion to simulate the conditions in the stomach and small intestine. Moreover, culturing the cells on inserts permits the measurement of iron transport. The cellular iron uptake is determined by direct measurements using radioisotopes, or indirectly by measurement of ferritin, the intracellular storage form of iron. There is a good correlation between Caco-2 cell uptake and human iron bioavailability for a number of dietary factors known to affect iron absorption. However, recent data suggest that in some cases there is no correlation. Possible reasons for such discrepancies, the benefits, and limitations of the Caco-2 cell model are discussed. In conclusion, in vitro experiments with Caco-2 cells are important tools for ranking foods with respect to bioavailability, for mechanistic studies of iron absorption, and for studies of dietary factors influencing absorption. The results need to be confirmed in humans.

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Kaltsas, G. A., D. Papadogias, P. Makras, and A. B. Grossman. "Treatment of advanced neuroendocrine tumours with radiolabelled somatostatin analogues." Endocrine-Related Cancer 12, no. 4 (December 2005): 683–99. http://dx.doi.org/10.1677/erc.1.01116.

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Neuroendocrine tumours (NETs) constitute a heterogeneous group of tumours that frequently express cell membrane-specific peptide receptors, such as somatostatin receptors (SSTRs), and of which gastroenteropancreatic (GEP), carcinoid and pancreatic islet cell tumours exhibit the highest expression of SSTRs. Radiolabelled receptor-binding somatostatin analogues (octreotide and lanreotide) act as vehicles to guide radioactivity to tissues expressing SSTRs, and can thus be used for their diagnosis and treatment. After the localization of NETs bearing SSTRs with 111In-octreotide (OctreoScan), a number of radioisotopes with different physical properties have been used for their treatment. The administration of high doses of the Auger electron and γ-emitter 111In-diethylenetriaminepenta-acetic acid (DTPA)0,octreotide in patients with metastatic tumours has been associated with considerable symptomatic improvement but relatively few and short-lived objective tumour responses. The use of another radiolabelled somatostatin analogue coupled with 90Y, a pure β-emitter, 90Y-1,4,7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid (DOTA)0,Tyr3,octreotide (90Y-DOTATOC, OctreoTher), was associated with 10–30% objective tumour response rates, and appears to be particularly effective in larger tumours. 111In- and 90Y-DOTA-lanreotide has also been used for the treatment of NETs although its therapeutic efficacy is probably inferior to that of octreotide-based radiopharmaceuticals. More recently, treatment with 177Lu-DOTA0,Tyr3octreotate (177Lu-DOTATATE), which has a higher affinity for the SSTR subtype 2, resulted in approximately 30% complete or partial tumour responses; this radiopharmaceutical is particularly effective in smaller tumours. Furthermore, treatment using both 90Y-DOTATOC and 177Lu-DOTA0,Tyr3octreotate seems promising, as the combination of these radiopharmaceuticals could be effective in tumours bearing both small and large lesions. Tumour regression is positively correlated with a high level of uptake on 111In-octreotide scintigraphy, limited tumour mass and good performance status. In general, better responses have been obtained in GEP tumours than other NETs. The side effects of this form of therapy are relatively few and mild, particularly when kidney-protective agents are used. Treatment with radiolabelled somatostatin analogues presents a promising tool for the management of patients with inoperable or disseminated NETs, and particularly GEP tumours.

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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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Susmallian, Sergio, Alina Filyavich, Ioana Maiershon, Ilan Charuzi, and Mordechai Lorberboym. "Dynamic Radioisotope Scintigraphy for Gastric Banding Adjustment." Obesity Surgery 14, no. 4 (April 1, 2004): 520–23. http://dx.doi.org/10.1381/096089204323013532.

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Badiali, Marco, Antonio D'Agostini, Anna Maria Filippis, Stefano Ginanni Corradini, Antonio Grossi Spera, Carla Lubrano, Rita Massa, Annarita Eramo, and Giovanni Francesco Scopinaro. "Patency of Anastomoses after Bilio-Intestinal Bypass: Radioisotope Demonstration." Obesity Surgery 11, no. 5 (October 1, 2001): 615–18. http://dx.doi.org/10.1381/09608920160557110.

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Schrey, M. P., H. J. Clark, and S. Franks. "The dopaminergic regulation of anterior pituitary 45Ca2+ homeostasis and prolactin secretion." Journal of Endocrinology 108, no. 3 (March 1986): 423–29. http://dx.doi.org/10.1677/joe.0.1080423.

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ABSTRACT A role for the regulation of cellular Ca2+ homeostasis in the dopaminergic control of prolactin secretion was investigated in rat anterior pituitary glands. Withdrawal of dopamine stimulated the uptake of 45Ca2+ into hemipituitary tissue by 48% after 3 min. Radioisotope desaturation from tissue prelabelled with 45Ca2+ was significantly retarded in the presence of dopamine. Withdrawal of dopamine rapidly stimulated 45Ca2+ efflux from prelabelled tissue by 79% and was accompanied by a three- to fourfold rise in prolactin secretion. The 45Ca2+ efflux response to dopamine withdrawal was reduced in tissue prelabelled in the presence of dopamine. Agonist displacement with metoclopramide mimicked the effect of dopamine withdrawal on 45Ca2+ efflux and prolactin secretion. These observations demonstrate that the stimulation of prolactin release by dopamine withdrawal is accompanied by a redistribution of cellular Ca2+ and support the hypothesis that dopamine inhibits secretion by decreasing Ca2+ influx in the mammotroph cell. J. Endocr. (1986) 108, 423–429

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Tryniszewski, W. "Multidirectional Assessment of Bone Structure Including Radioisotopic Analysis in Perimenopausal Women." Acta Endocrinologica (Bucharest) 14, no. 4 (2018): 439–46. http://dx.doi.org/10.4183/aeb.2018.439.

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MATSUNO, AKIRA, NAOKO SANNO, SHIGEYUKI TAHARA, AKIRA TERAMOTO, R. YOSHIYUKI OSAMURA, HIROMI WADA, MINEKO MURAKAMI, HIDEKI TANAKA, and TADASHI NAGASHIMA. "Silent Somatotroph Adenoma, Detected by Catalyzed Signal Amplification and Non-radioisotopic In situ Hybridization." Endocrine Journal 46, Suppl (1999): S81—S84. http://dx.doi.org/10.1507/endocrj.46.suppl_s81.

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LaBrecque, John J. "Radioisotope induced X-ray emission (RIXE) studies in life sciences." Biological Trace Element Research 26-27, no. 1 (July 1990): 143–48. http://dx.doi.org/10.1007/bf02992667.

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Sener, A., R. Ramirez, and W. J. Malaisse. "A sensitive radioisotopic assay of myo-inositol: Its application to rat pancreatic islets." Biochemical Medicine and Metabolic Biology 47, no. 2 (April 1992): 116–23. http://dx.doi.org/10.1016/0885-4505(92)90015-q.

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De Micheli, A., C. Bordone, F. Castagnola, L. Cataldi, R. Costa, F. Della Rovere, P. Erba, et al. "Radioisotopic evaluation of the prevalence of silent coronary artery disease in high-risk diabetic patients." Diabetes Research and Clinical Practice 50 (September 2000): 305. http://dx.doi.org/10.1016/s0168-8227(00)81039-6.

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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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Mello, Maria Eduarda, Rodrigo C. Flamini, Rossana Corbo, and Marcelo Mamede. "Radioiodine concentration by the thymus in differentiated thyroid carcinoma: report of five cases." Arquivos Brasileiros de Endocrinologia & Metabologia 53, no. 7 (October 2009): 874–79. http://dx.doi.org/10.1590/s0004-27302009000700012.

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The radioactive iodine has been used with great value as a diagnostic and therapeutic method in patients with differentiated thyroid carcinoma previously submitted to total thyroidectomy. False-positive whole-body scans may occur due to misinterpretation of the physiologic distribution of the radioisotope or lack of knowledge on the existence of other pathologies that could eventually present radioiodine uptake. Thymic uptake is an uncommon cause of false-positive whole-body scan, and the mechanism through which it occurs is not completely understood. The present paper reports five cases of patients with differentiated thyroid cancer who presented a mediastinum uptake of radioiodine in a whole-body scan during follow-up. The patients had either histological or radiological confirmation of the presence of residual thymus gland. It is very important to know about the possibility of iodine uptake by the thymus in order to avoid unnecessary treatment, such as surgery or radioiodine therapy.

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Das, Tirtha K., and Ross L. Cagan. "Non-mammalian models of multiple endocrine neoplasia type 2." Endocrine-Related Cancer 25, no. 2 (February 2018): T91—T104. http://dx.doi.org/10.1530/erc-17-0411.

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Twenty-five years ago, RET was identified as the primary driver of multiple endocrine neoplasia type 2 (MEN2) syndrome. MEN2 is characterized by several transformation events including pheochromocytoma, parathyroid adenoma and, especially penetrant, medullary thyroid carcinoma (MTC). Overall, MTC is a rare but aggressive type of thyroid cancer for which no effective treatment currently exists. Surgery, radiation, radioisotope treatment and chemotherapeutics have all shown limited success, and none of these approaches have proven durable in advanced disease. Non-mammalian models that incorporate the oncogenic RET isoforms associated with MEN2 and other RET-associated diseases have been useful in delineating mechanisms underlying disease progression. These models have also identified novel targeted therapies as single agents and as combinations. These studies highlight the importance of modeling disease in the context of the whole animal, accounting for the complex interplay between tumor and normal cells in controlling disease progression as well as response to therapy. With convenient access to whole genome sequencing data from expanded thyroid cancer patient cohorts, non-mammalian models will become more complex, sophisticated and continue to complement future mammalian studies. In this review, we explore the contributions of non-mammalian models to our understanding of thyroid cancer including MTC, with a focus onDanio rerioandDrosophila melanogaster(fish and fly) models.

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Eastell, R., L. Hampton, A. Colwell, J. R. Green, A. M. A. Assiri, R. Hesp, R. G. G. Russell, and J. Reeve. "13. Validation of collagen crosslinks as markers of bone resorption: comparison with radioisotopic method." Bone 12, no. 4 (1991): 289–90. http://dx.doi.org/10.1016/8756-3282(91)90090-6.

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Weigand, E., Ursula Helbig, and M. Kirchgessner. "Radioisotope-dilution technique for determining endogenous manganese in feces of the growing rat." Biological Trace Element Research 10, no. 4 (October 1986): 281–92. http://dx.doi.org/10.1007/bf02802396.

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Goncharov, N. P. "Androgens: A lecture." Problems of Endocrinology 42, no. 4 (August 15, 1996): 28–31. http://dx.doi.org/10.14341/probl12071.

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Androgens (Greek aner, andros - male and genesis - origin) - compounds with the properties of the male sex hormone testosterone (T). T (androst-4-en-17p-ol-3-one; molecular mass 288.41) is a derivative of androstane. In 1935, Laker from 100 kg of testes of bulls for the first time isolated 10 mg of a pure substance, which he called testosterone. Its biological activity was 10 times higher than that of androsterone known at that time. Based on a number of studies, it has been suggested that T is a 17-dihydro derivative of androstenedione. Soon, the hypothetical structure of T was deciphered and its synthesis was carried out. This was a prologue for the synthesis of dozens of derivatives of T with desired properties. Later, a large number of natural androgens secreted by the testes and adrenal glands, as well as their metabolic products excreted in the urine, were isolated from various biological environments of humans and animals. Biosynthesis and metabolism of androgens. Using various methods, including chemical-analytical, radioisotope, chromatographic, perfusion of testes, studying metabolic products excreted in the urine, it was possible to develop a conceptual scheme of androgen synthesis. Cholesterol ester, accumulated by Leydig cells of the testis, is a source of androgen formation.

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Boldrini, E., G. Mariani, A. Clerico, G. Forotti, G. Boni, F. Marchini, A. Troilo, E. Matteucci, and O. Giampietro. "Extensive evaluation of the renal function by a radioisotopic method in diabetic people: More than an advantage, few limitations." Diabetes Research and Clinical Practice 50 (September 2000): 264. http://dx.doi.org/10.1016/s0168-8227(00)80897-9.

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Lobo, M. V., and E. T. Marusic. "Effect of angiotensin II, ATP, and ionophore A23187 on potassium efflux in adrenal glomerulosa cells." American Journal of Physiology-Endocrinology and Metabolism 250, no. 2 (February 1, 1986): E125—E130. http://dx.doi.org/10.1152/ajpendo.1986.250.2.e125.

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Angiotensin II stimulus on perifused bovine adrenal glomerulosa cells elicited an increase in 86Rb efflux from cells previously equilibrated with the radioisotope. When 45Ca fluxes were measured under similar conditions, it was observed that Ca and Rb effluxes occurred within the first 30 s of the addition of the hormone and were independent of the presence of external Ca. The 86Rb efflux due to angiotensin II was inhibited by quinine and apamin. The hypothesis that the angiotensin II response is a consequence of an increase in the K permeability of the glomerulosa cell membrane triggered by an increase in cytosolic Ca is supported by the finding that the divalent cation ionophore A23187 also initiated 86Rb or K loss (as measured by an external K electrode). This increased K conductance was also seen with 10(-4) M ATP. Quinine and apamin greatly reduced the effect of ATP or A23187 on 86Rb or K release in adrenal glomerulosa cells. The results suggest that Ca-dependent K channels or carriers are present in the membranes of bovine adrenal glomerulosa cells and are sensitive to hormonal stimulus.

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Drager, Luciano F., Thauany M. Tavoni, Vanessa M. Silva, Raul D. Santos, Rodrigo P. Pedrosa, Luiz A. Bortolotto, Carmen G. Vinagre, Vsevolod Y. Polotsky, Geraldo Lorenzi-Filho, and Raul C. Maranhao. "Obstructive sleep apnea and effects of continuous positive airway pressure on triglyceride-rich lipoprotein metabolism." Journal of Lipid Research 59, no. 6 (April 8, 2018): 1027–33. http://dx.doi.org/10.1194/jlr.m083436.

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This study aimed to explore lipoprotein metabolism in obstructive sleep apnea (OSA) and the effects of continuous positive airway pressure (CPAP). We studied 15 men with severe OSA [apnea-hypopnea index (AHI) ≥30 events/hour] and 12 age-, BMI-, and waist circumference-matched volunteers without OSA (AHI <5 events/hour). Carotid intima-media thickness (CIMT) was determined by a blind examiner. After 12 h fasting, a triglyceride-rich chylomicron-like emulsion, labeled with [14C]cholesteryl oleate and [3H]triolein, was injected intravenously followed by blood sample collection at preestablished times. Fractional clearance rate (FCR) of the radiolabeled lipids was estimated by compartmental analysis of radioisotope decay curves. Compared with controls, patients with OSA showed a significant delay in both cholesteryl ester FCR (0.0126 ± 0.0187 vs. 0.0015 ± 0.0025 min−1; P = 0.0313) and triglycerides FCR (0.0334 ± 0.0390 vs. 0.0051 ± 0.0074 min−1; P = 0.0001). CIMT was higher in the OSA group: 620 ± 17 vs. 725 ± 29 µm; P = 0.004. Cholesteryl ester FCRs were inversely related to total sleep time <90% (r = −0.463; P = 0.029) and CIMT (r = −0.601; P = 0.022). The triglyceride FCR was inversely correlated with AHI (r = −0.537; P = 0.04). In a subgroup of patients treated with CPAP for 3 months (n = 7), triglyceride FCR increased 5-fold (P = 0.025), but the cholesteryl ester FCR was unchanged. In conclusion, severe OSA decreased lipolysis of triglyceride-rich lipoproteins and delayed removal of remnants. CPAP treatment may be effective to restore the lipolysis rates.

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Simonson, D. C., and R. A. DeFronzo. "Indirect calorimetry: methodological and interpretative problems." American Journal of Physiology-Endocrinology and Metabolism 258, no. 3 (March 1, 1990): E399—E412. http://dx.doi.org/10.1152/ajpendo.1990.258.3.e399.

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The technique of indirect calorimetry is now widely used to examine rates of energy production and substrate oxidation in humans. Although the basic principles of indirect calorimetry are well established, it is important to recognize that there are several potential pitfalls in the methodology and data interpretation that must be appreciated to properly understand and apply the results derived from this technique. In particular, one must recognize that the fundamental measurement provided by indirect calorimetry is the net disappearance rate of a substrate regardless of the metabolic interconversions that the substrate may undergo before its disappearance from its metabolic pool. Under most circumstances, direct oxidation represents the major route by which a substrate disappears from its metabolic pool, and the two terms are often used interchangeably. However, under conditions when rates of gluconeogenesis, ketogenesis, or lipogenesis are elevated, the presumed equivalence between oxidation and disappearance may no longer apply, even though the actual measurements derived from indirect calorimetry remain valid. When indirect calorimetry is combined with other in vivo metabolic techniques (e.g., the insulin clamp or radioisotope turnover methods) it can provide a powerful tool for noninvasively examining complex metabolic processes.

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Ruan, Maomei, Min Liu, Qianggang Dong, and Libo Chen. "Iodide- and Glucose-Handling Gene Expression Regulated by Sorafenib or Cabozantinib in Papillary Thyroid Cancer." Journal of Clinical Endocrinology & Metabolism 100, no. 5 (May 1, 2015): 1771–79. http://dx.doi.org/10.1210/jc.2014-3023.

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Abstract Context: The aberrant silencing of iodide-handling genes accompanied by up-regulation of glucose metabolism presents a major challenge for radioiodine treatment of papillary thyroid cancer (PTC). Objective: This study aimed to evaluate the effect of tyrosine kinase inhibitors on iodide-handling and glucose-handling gene expression in BHP 2-7 cells harboring RET/PTC1 rearrangement. Main Outcome Measures: In this in vitro study, the effects of sorafenib or cabozantinib on cell growth, cycles, and apoptosis were investigated by cell proliferation assay, cell cycle analysis, and Annexin V-FITC apoptosis assay, respectively. The effect of both agents on signal transduction pathways was evaluated using the Western blot. Quantitative real-time PCR, Western blot, immunofluorescence, and radioisotope uptake assays were used to assess iodide-handling and glucose-handling gene expression. Results: Both compounds inhibited cell proliferation in a time-dependent and dose-dependent manner and caused cell cycle arrest in the G0/G1 phase. Sorafenib blocked RET, AKT, and ERK1/2 phosphorylation, whereas cabozantinib blocked RET and AKT phosphorylation. The restoration of iodide-handling gene expression and inhibition of glucose transporter 1 and 3 expression could be induced by either drug. The robust expression of sodium/iodide symporter induced by either agent was confirmed, and 125I uptake was correspondingly enhanced. 18F-fluorodeoxyglucose accumulation was significantly decreased after treatment by either sorafenib or cabozantinib. Conclusions: Sorafenib and cabozantinib had marked effects on cell proliferation, cell cycle arrest, and signal transduction pathways in PTC cells harboring RET/PTC1 rearrangement. Both agents could be potentially used to enhance the expression of iodide-handling genes and inhibit the expression of glucose transporter genes.

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Elmore, David. "Ultrasensitive radioisotope, stable-isotope, and trace-element analysis in the biological sciences using tandem accelerator mass spectrometry." Biological Trace Element Research 12, no. 1 (April 1987): 231–45. http://dx.doi.org/10.1007/bf02796683.

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Wang, J. F., G. P. Becks, E. Hanada, K. D. Buckingham, I. D. Phillips, and D. J. Hill. "Hormonal regulation of insulin-like growth factor (IGF)-binding proteins secreted by isolated sheep thyroid epithelial cells: relationship with iodine organification." Journal of Endocrinology 130, no. 1 (July 1991): 129–40. http://dx.doi.org/10.1677/joe.0.1300129.

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ABSTRACT Isolated sheep thyroid follicles release specific insulinlike growth factor-binding proteins (IGFBPs). Since IGFBPs can modulate IGF bioactivity, at least in vitro, their presence in thyroid tissues may influence synergistic interactions between TSH and endogenous IGF-I or -II which are known to control both thyroid growth and function. We have examined the hormonal control of IGFBP release in relation to iodine organification. Sheep thyroid follicles were isolated by incubation with collagenase and differential centrifugation, grown in Coon's modified Ham's F12M medium with the addition of transferrin, glycylhistidyl-lysine, somatostatin (3H), TSH, cortisol and insulin (6H), and maintained in OH (hormone-free) or 3H medium with or without further supplements for 48 h. Conditioned culture medium was separated by 8% sodium dodecyl sulphate (SDS)–polyacrylamide gel electrophoresis, transferred to nitrocellulose and incubated with 125I-labelled IGF-II followed by autoradiography (ligand blot). Additionally, the radioactive bands were cut from the filters and quantified by γ-spectrometry. Iodine organification was assessed by incubation of follicles with 106 c.p.m. Na125I for 3 h before washing, solubilization in 0·1 mol NaOH/l and the precipitation of organified radioisotope with 10% (v/v) trichloroacetic acid. Cells conditioned in OH or 3H medium released specific IGFBPs of 46, 34, 28 and 19 kDa on ligand blot analysis. The proteins of 34 and 19 kDa were immunopositive on Western blot analysis using anti-bovine IGFBP-2 antiserum. The 46-kDa IGFBP was retained by Concanavalin A–Sepharose chromatography and demonstrated to be glycoprotein. This is probably ovine IGFBP-3. The addition of TSH, or TSH plus cortisol, to OH or 3H medium significantly decreased the 125I-labelled IGF-II associated with the 34- and 28-kDA IGFBP species. All IGFBP species were substantially reduced in 6H medium, which was predominantly due to the effects of TSH and cortisol. When total 125I-labelled IGF-II associated with IGFBPs was considered, a significant (P < 0·01) inverse correlation existed between IGFBP activity and iodine organification in the same cultures; the latter being greatest in OH or 3H medium supplemented with TSH and cortisol. None of these hormone additions altered the endogenous release of IGF-II by the cells. These results suggest that endogenous IGFs, under hormonal control, may modulate the action of endogenous IGF in the regulation of thyroid function. Journal of Endocrinology (1991) 130, 129–140

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Lobo, M. V., and E. T. Marusic. "Angiotensin II causes a dual effect on potassium permeability in adrenal glomerulosa cells." American Journal of Physiology-Endocrinology and Metabolism 254, no. 2 (February 1, 1988): E144—E149. http://dx.doi.org/10.1152/ajpendo.1988.254.2.e144.

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In previous studies it was shown that angiotensin II causes a Ca-dependent increase in the K permeability of bovine adrenal glomerulosa cells [Am. J. Physiol. 250 (Endocrinol. Metab. 13): E125-E130, 1986]. Here we show that angiotensin II causes a significant and prolonged reduction in the 86Rb release immediately after the transient rise in 86Rb efflux. This inhibition was dose related. Apamin (100 nM) and tetraethylammonium (10 mM) completely abolished the initial transient rise in 86Rb efflux without affecting the latter sustained phase of reduced radioisotope release. On the contrary, the effect of angiotensin II on the second phase was absent when Ca was removed from the perifusion medium or replaced with Sr, but the effect on the early transient phase of 86Rb efflux was maintained in the absence of external Ca. An additional finding was the increased coefficient rate of 86Rb efflux that occurred when the cells were depolarized with 12 mM K. However, this effect was not observed when the inhibitory phase due to angiotensin II was fully developed and Ca was present in the external media. On the other hand, the biphasic effect of angiotensin II was still present in depolarized cells. These results suggest that angiotensin II may modulate membrane potential by changes in K permeability of the bovine adrenal glomerulosa cells.

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Pasquali, D., F. Y. Tseng, C. S. Rani, and J. B. Field. "Inhibition of intermediary metabolism by amiodarone in dog thyroid slices." American Journal of Physiology-Endocrinology and Metabolism 259, no. 4 (October 1, 1990): E529—E533. http://dx.doi.org/10.1152/ajpendo.1990.259.4.e529.

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Amiodarone, an iodine-containing antiarrhythmic drug, has been reported to interfere with thyroid function and thyroid hormone metabolism. We studied the effects of amiodarone on basal and agonist [thyroid-stimulating hormone (TSH), phorbol ester, or carbachol]-stimulated glucose oxidation, 32PO4 incorporation into phospholipids, and adenosine 3',5'-cyclic monophosphate (cAMP) concentration in dog thyroid slices. Slices were preincubated with amiodarone at 37 degrees C for 1 h before the addition of agonist and the appropriate radioisotope. cAMP stimulation was measured after 20 min, glucose oxidation for 45 min, and 32PO4 incorporation into phospholipids for 2 h. Amiodarone (0.5 mM) had no effect on basal 14CO2 formation or 32PO4 incorporation into phospholipids but significantly inhibited TSH, phorbol ester, and carbachol stimulation of these parameters. It also inhibited cAMP stimulation by TSH. Inhibition of TSH-stimulated [14C]glucose oxidation was also obtained with another iodide-containing compound, iopanoic acid (0.5 mM), but not with iothalamate (up to 10 mM). Inhibition by amiodarone was still present, but to a lesser extent, when it was added at the same time as the agonist. Inhibition of stimulated [14C]glucose oxidation persisted even after the slices were incubated without amiodarone for 6 h. Inhibition by amiodarone, in contrast to that by inorganic iodide, was not prevented by 1 mM methimazole added at the same time as amiodarone. These results indicate that the inhibitory effects of amiodarone on thyroid function are not due to dissociation of iodide from the molecule.

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Jacobs, R. M., J. T. Boyce, and G. J. Kociba. "Flow cytometric and radioisotopic determanations of platelet survival time in normal cats and feline leukemia virus-infected cats." Cytometry 7, no. 1 (January 1986): 64–69. http://dx.doi.org/10.1002/cyto.990070109.

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Nawarathna, Nadeesha Jeewan, NR Kumarasinghe, D. Chandrasekara, P. Rathnayake, BMRS Balasooriya, and RJK Senevirathne. "Thoracic Wall Metastasis from an Occult Thyroid Follicular Carcinoma." World Journal of Endocrine Surgery 6, no. 3 (2014): 119–22. http://dx.doi.org/10.5005/jp-journals-10002-1152.

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ABSTRACT Occult thyroid carcinoma presenting with clinically apparent metastasis is rare and is a diagnostic challenge. Here, we report a 67-year-old male who presented with a left side chest wall mass resembling a soft tissue sarcoma of 1 year duration. The mass showed rapid enlargement at the latter end of its course, following an initial asymptomatic period. Imaging studies showed a soft tissue mass eroding into several ribs. Wide local excision with primary reconstruction was performed. Histological studies and immune staining revealed metastasis from a follicular thyroid carcinoma. Total thyroidectomy followed, confirming the diagnosis. Postoperatively, radioisotope ablation (I131) was done. A suppression dose of thyroxin was continued with regular thyroglobulin assays. Painful bone metastasis responded well to analgesics, bisphosphonates and external beam radiotherapy. Follicular carcinoma comprises 10 to 15% of thyroid malignancies. Localized thyroid carcinoma has a very good prognosis, 10 years survival rates reducing by 50% with metastatic disease. Commonly, thyroid cancer presents as detectable thyroid nodules, 25% having metastasis. In contrast, metastatic manifestations are reported in less than 5% of occult thyroid cancers. How to cite this article Nawarathna NJ, Kumarasinghe NR, Chandrasekara D, Rathnayake P, Balasooriya BMRS, Senevirathne RJK. Thoracic Wall Metastasis from an Occult Thyroid Follicular Carcinoma. World J Endoc Surg 2014;6(3):119-122.

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Yagi, Masashi, Luke Arentsen, Ryan M. Shanley, Clifford J. Rosen, Louis S. Kidder, Leslie C. Sharkey, Douglas Yee, Masahiko Koizumi, Kazuhiko Ogawa, and Susanta K. Hui. "A Dual-Radioisotope Hybrid Whole-Body Micro-Positron Emission Tomography/Computed Tomography System Reveals Functional Heterogeneity and Early Local and Systemic Changes Following Targeted Radiation to the Murine Caudal Skeleton." Calcified Tissue International 94, no. 5 (February 23, 2014): 544–52. http://dx.doi.org/10.1007/s00223-014-9839-6.

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38

Byrne, A. R., and M. Dermelj. "Comprehensive RNAA of cadmium, cobalt, nickel, and copper using109Cd,57Co, and reactor-produced67Cu as radioisotopic yield monitors." Biological Trace Element Research 43-45, no. 1 (December 1994): 87–94. http://dx.doi.org/10.1007/bf02917303.

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39

Kossintseva, Iren, Susan Wong, Ed Johnstone, Larry Guilbert, David M. Olson, and B. F. Mitchell. "Proinflammatory cytokines inhibit human placental 11β-hydroxysteroid dehydrogenase type 2 activity through Ca2+ and cAMP pathways." American Journal of Physiology-Endocrinology and Metabolism 290, no. 2 (February 2006): E282—E288. http://dx.doi.org/10.1152/ajpendo.00328.2005.

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Excessive fetal exposure to glucocorticoids has been implicated in the etiology of adult metabolic and cardiovascular disease. Placental 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) may protect the fetus from excessive glucocorticoid exposure. Maternal stress may be accompanied by elevated levels of cortisol and increased proinflammatory cytokines [interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α)]. We hypothesize that proinflammatory cytokines inhibit human placental 11β-HSD activity. We incubated explant cultures of term human placental villi in the presence or absence of 10 ng/ml IL-1β, IL-6, or TNF-α, with or without agonists or antagonists of intracellular Ca2+ and adenylyl cyclase. Activity for 11β-HSD2 was estimated using a radioisotope assay, and mRNA was measured using quantitative RT-PCR. All cytokines significantly ( P ≤ 0.05) reduced 11β-HSD2 activity (>75% suppression); maximal inhibition occurred within 2 h and was maintained for at least 24 h. The IL-1β-induced inhibitory activity was attenuated using a Ca2+ channel blocker (nifedipine), an intracellular Ca2+ antagonist [8-( N, N-diethylamino)octyl-3,4,5-trimethoxybenzoate], or the adenylyl cyclase stimulant forskolin. Conversely, 11β-HSD2 activity was diminished in the presence of the Ca2+ ionophore A-23187 or the adenylyl cyclase inhibitor SQ-22536. mRNA levels for 11β-HSD2 were not changed by any of the treatments. Proinflammatory cytokines inhibit human placental 11β-HSD2 activity through a mechanism that involves increased intracellular Ca2+ and inhibition of adenylyl cyclase. This could result in excessive fetal exposure to maternal cortisol. This mechanism might mediate part of the increased risk of metabolic and cardiovascular disease in adult offspring.

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Jung, Ik-Rak, Becky Tu-Sekine, Frederick Anokye-Danso, Rexford S. Ahima, and Sangwon Kim. "The Role of Inositol Phosphate Multikinase (IPMK) in Time Restricted Feeding in Animal Model." Journal of the Endocrine Society 5, Supplement_1 (May 1, 2021): A326—A327. http://dx.doi.org/10.1210/jendso/bvab048.666.

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Abstract Obesity is a major public health problem of the U.S. and is associated with diabetes, cardiovascular diseases and other diseases. Most research studies focus on excessive food consumption as the main cause of obesity. However, emerging data indicate that the timing of feeding can have significant effects on body weight and metabolism. Numerous studies in animals and small clinical studies in humans have shown that eating erratically over the 24 hour period or out of phase with the circadian rhythm predisposes toward weight gain, steatosis, dyslipidemia, insulin resistance and diabetes. Furthermore, studies indicate that restricting food intake to the active period synchronizes the circadian rhythm and metabolism, enhances weight loss and improves metabolic outcomes. Time restricted feeding (TRF) increases the amplitudes of clock gene expression and pathways mediating nutrient sensing and hepatic metabolism. However, the mechanisms mediating the effects of TRF are not fully understood. Here we characterized mice (10 week-old) fed a high-fat diet ad libitum (ALF) or from 7 pm to 7 am (TRF) for 2 weeks. The basal glucose production rate was similar between the two groups. Under hyperinsulinemic-euglycemic clamp, the glucose infusion rate (GIR) was significantly greater in TRF group compared to ALF group indicating an increase in insulin sensitivity. Using radioisotopic tracers, we demonstrated that the hepatic glucose production (HGP) was significantly reduced and the glucose disappearance rate was increased in TRF group compared to ALF group. Moreover, a biochemical analyses of liver tissues revealed that Inositol phosphate multikinase (IPMK) act as a key enzyme for inositol polyphosphate biosynthesis and play a role in insulin-, nutrient-, and energy-mediated metabolic signaling, was increased during TRF. Moreover, deletion of IPMK in hepatocytes decreased insulin stimulated AKT phosphorylation while increased lipid accumulation and gluconeogenesis. Importantly, hepatic deletion of IPMK attenuated the beneficial effects of TRF suggesting that IPMK in the liver may contributes to beneficial effects of TRF. Our findings provide the potential mechanism by which TRF confers the beneficial effects and may provide a novel therapeutic strategy for treating diabetes.

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Rasschaert, J., WJ Malaisse, and K. Tanigawa. "Ontogeny of FAD-linked glycerophosphate dehydrogenase in rat pancreatic islets." Reproduction, Fertility and Development 8, no. 3 (1996): 443. http://dx.doi.org/10.1071/rd9960443.

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The activities of the mitochondrial FAD-linked glycerophosphate dehydrogenase (m-GDH), glutamate dehydrogenase, alpha-ketoglutarate dehydrogenase, glutamate-pyruvate transaminase (GPT) and glutamate-oxaloacetate transaminase were measured in islet and liver homogenates from fetal, neonatal, adult male, adult female, pregnant and lactating rats. Either parallel or dissociated ontogenic changes were observed in islet and liver homogenates. The activity of islet m-GDH was slightly, albeit not significantly, lower in neonates than in adult rats, comparable in male and female adult animals, unaffected by pregnancy, and increased during lactation. It was much higher in fetal or adult islets cultured for 7 days than in freshly isolated islets from adult rats. In cultured islets from adult rats, the increase in m-GDH activity coincided with a dramatic decrease of GPT activity, a situation the mirror image of that found in several animal models of non-insulin-dependent diabetes mellitus. The intrinsic properties of m-GDH, as judged by comparison of measurements made by either a radioisotopic or a colorimetric procedure, were not identical in islet and liver homogenates and differed between fetal and adult islets, suggesting the existence of distinct iso-enzymes. These findings illustrate adaptive changes of islet enzymes, with exclusive or partial mitochondrial location, in ontogenic situations characterized by a remodelling of fuel homeostasis.

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Fairweather-Tait, Susan J., and Birgit Teucher. "Calcium Bioavailability in Relation to Bone Health." International Journal for Vitamin and Nutrition Research 72, no. 1 (January 1, 2002): 13–18. http://dx.doi.org/10.1024/0300-9831.72.1.13.

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A well established stable isotope technique exists for measuring calcium absorption from single foods and meals, but the long term effects of calcium on bone health cannot be assessed from acute bioavailability studies. Bone health depends primarily on the degree of mineralization, measured as bone mineral density (BMD), and phenotypic variations depend on genetic and environmental factors including calcium supply. Since almost all retained calcium is used for bone mineralization and remodeling, BMD can be used as a long-term (> six months) marker of dietary calcium bioavailability. However, BMD is a very insensitive marker of calcium bioavailability, so its use in dietary intervention studies is restricted to periods of significant bone growth or loss. Biochemical markers of bone metabolism may be used to predict the overall bioavailability of dietary calcium over a shorter time period (> four weeks), but they have a high coefficient of variation, so may not be appropriate for some dietary intervention studies. A group of European laboratories is currently developing an alternative approach using a long-lived radioisotope (41Ca) to label bone calcium and to directly measure the rate of calcium loss from urinary excretion data. The efficiency of calcium absorption is inversely related to intake; whole body balance of the mineral is dependent on rates of absorption and excretion and limited by calcium-binding substances in the gut. Dietary data and indirect measures of bone health indicate that bioavailability is important when habitual intakes are low, especially during periods of bone growth or loss. Further research is required to quantify the effects of major dietary modulators of calcium balance on bone health and to understand their relationship with genetic and physiological variables.

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Tariq, Muhammad Ashraf, and Ivor L. Preiss. "Fluctuations in Fe, Cu, Zn, Br, As, Se, and Rb concentrations in C57L/J mice bearing BW7756 murine hepatoma using radioisotope-induced X-ray fluorescence." Biological Trace Element Research 42, no. 2 (August 1994): 97–114. http://dx.doi.org/10.1007/bf02785382.

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King, KR, JM Gooden, and EF Annison. "Acetate Metabolism in the Mammary Gland of the Lactating Ewe." Australian Journal of Biological Sciences 38, no. 1 (1985): 23. http://dx.doi.org/10.1071/bi9850023.

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Acetate metabolism in the mammary gland of lactating ewes was studied by continuous infusion of radioisotopic [U-14C)sodium acetate and measurement of mammary gland arteriovenous difference and blood flow. Entry rate of acetate into the whole body averaged 75 � 7 /Lmol min -I kg -I liveweight and 22' I � 2 . 7 % of total C02 production was derived from acetate. Acetate was both utilized and produced by the mammary gland. Acetate uptake was related linearly (r2 = o� 94) to arterial concentration and gross utilization of acetate accounted for 16' 2 � 2 . 6 % of whole-body entry rate. Endogenous acetate production by the mammary gland increased linearly (r2 = O� 90) as milk yield rose, and accounted for 25 . 6 � 2 . 7 % of the gross mammary utilization of acetate. The proportion of mammary C02 derived from acetate (22' 5 � 3' 9%) was similar to that of the whole body. The uptake of acetate, 3-hydroxybutyrate, esterified fatty acids and plasma free fatty acids accounted for about 25, 13, 60 and 4% of milk fatty acid carbon respectively, after correction for the oxidation of acetate, but not of the other substrates. Metabolism of acetate in the mammary glands of lactating ewes appears quantitatively more important than that in cows, b~t similar to that in goats.

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Hu, Jesse SL, and Rajeev Parameswaran. "A Case of Miliary Nodules, Hemoptysis and Hot Thyroid Cancer: Unusual Presentation of Papillary Thyroid Cancer." World Journal of Endocrine Surgery 7, no. 3 (2015): 72–75. http://dx.doi.org/10.5005/jp-journals-10002-1174.

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ABSTRACT Background Papillary thyroid carcinoma is the commonest thyroid cancer. Patients usually present with thyroid nodule and rarely with hyperthyroidism such that 2009 ATA guidelines recommended that cytological evaluation is not necessary in patients with hyperfunctioning nodules as they rarely harbor malignancy. We report a case of an unusual presentation of metastatic papillary thyroid carcinoma in a young patient. Case presentation A 17-year-old girl, presented to our hospital with 3 days of fever, cough and hemoptysis. Chest X-ray showed extensive miliary nodules and was treated for presumed miliary tuberculosis. Biochemical investigations revealed a hyperthyroid state (fT4 55.7 TSH < 0.02), with negative antibodies (TRAB and TSI). Radioisotope scan showed increased uptake on right lobe. She underwent bronchoscopy and biopsy which revealed metastatic papillary thyroid carcinoma. Clinical examination revealed a small goiter with palpable cervical node at level III on the left. There were no clinical signs of Graves’ disease and she had no history of previous radiation or family history of endocrine disease. Ultrasound revealed multiple hypodense thyroid nodules with microcalcification and increased vascularity. Ultrasound of the neck showed the presence of abnormal lymphadenopathy. She underwent total thyroidectomy, bilateral central neck dissection and left lateral modified neck dissection. Histology showed 1.3 cm papillary thyroid carcinoma involving the left lobe and multifocal papillary thyroid microcarcinomas involving both lobes. Ten out of 27 nodes were involved. She was BRAF mutation positive. She recovered well postoperatively and was rendered hypothyroid. She underwent radioiodine ablation which showed no more disease in the neck but unfortunately there was no uptake in the lung metastases. Conclusion Metastatic papillary thyroid cancer developing in a young patient with hyperthyroidism is extremely rare and suggests a more aggressive behavior as confirmed by BRAF mutation. How to cite this article Hu JSL, Parameswaran R. A Case of Miliary Nodules, Hemoptysis and Hot Thyroid Cancer: Unusual Presentation of Papillary Thyroid Cancer. World J Endoc Surg 2015;7(3):72-75.

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Covert, RF, MD Schreiber, LJ Torgerson, RW Torgerson, and DJ Miletich. "Prediction of cerebral blood flow in fetal lambs by carotid artery ultrasonic flow transducer." Reproduction, Fertility and Development 8, no. 1 (1996): 157. http://dx.doi.org/10.1071/rd9960157.

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To determine whether common carotid artery blood flow measured with an ultrasonic flow transducer would predict brain blood flow in fetal sheep, we measured unilateral common carotid artery blood flow and compared this to simultaneous measurements of total brain blood flows made by radioisotope-labelled microsphere techniques. We studied anaesthetized, exteriorized fetal sheep with intact umbilical circulation after ligation of extracranial, extracerebral arteries and placement of a common carotid artery flow transducer; five fetuses at 120 d gestation had 19 total comparison measurements. As measured by microsphere technique, mean basal blood flow during undisturbed conditions to regional brain areas were similar to normal values reported for the exteriorized ovine fetus; these flows were highly correlated to fetal PaCO2 and successfully varied over a wide range (total brain 9.1-200.4 ml/min/100g and total cortex 6.1-153.1 ml/min/100g) in subsequent experimental conditions of hypercapnia or occluded blood flow. Blood flow as measured by flow transducer significantly correlated (P < or = 0.01) with microsphere measurements of blood flow to total brain (r = 0.56) and total cortex (r = 0.62); regional flow to cerebellum (r = 0.70) and thalamus (r = 0.60) also correlated to transducer measurements. Stronger correlations were observed at low-flow conditions to total brain (r = 0.83) and to total cortex (r = 0.90). As measured by microsphere technique, right and left cortical blood flows were highly correlated (P = 0.0001, r = 0.97), indicating that the flow transducer or surgical manipulation did not disturb the distribution of cerebral blood flow. The mean values for zero flow reference of the transducer were < 1.5% of mean basal flow values. It is concluded that the common carotid artery flow transducer technique developed in this study provides an accurate prediction of blood flow to total brain and total cortex over a wide range of values in fetal sheep. This technique provides a methodologic advantage to sequential experimental interventions and may prove advantageous to studies of fetal sheep cerebral circulation.

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Xiong, Zhouyi, Chunying Luo, Li Wang, Bin Xiong, and Jianneng Wu. "Establishing a diagnostic scale of subacute thyroiditis without radioisotope scanning." BMC Endocrine Disorders 20, no. 1 (May 27, 2020). http://dx.doi.org/10.1186/s12902-020-00554-z.

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Lucas-Herald, Angela, Therese Bradley, Pia Hermanns, Jeremy Jones, Morag Attaie, Elaine Thompson, Joachim Pohlenz, and Malcolm Donaldson. "Novel heterozygous thyrotropin receptor mutation presenting with neonatal hyperthyrotropinaemia, mild thyroid hypoplasia and absent uptake on radioisotope scan." Journal of Pediatric Endocrinology and Metabolism 26, no. 5-6 (January 1, 2013). http://dx.doi.org/10.1515/jpem-2012-0308.

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49

Birkenmeier, G., I. Kampfer, J. Kratzsch, and W. Schellenberger. "Human leptin forms complexes with alpha 2-macroglobulin which are recognized by the alpha 2-macroglobulin receptor/low density lipoprotein receptor-related protein." European Journal of Endocrinology, August 1, 1998, 224–30. http://dx.doi.org/10.1530/eje.0.1390224.

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OBJECTIVE: To identify binding proteins of leptin in human plasma. METHODS: Binding was evaluated by electrophoresis, size exclusion chromatography (SEC), Western blotting, and radioisotope labeling. Quantification of leptin and the different forms of alpha2-macroglobulin (alpha2-M) was performed by ELISA. RESULTS: Leptin interacts with the proteinase inhibitor, alpha2-M. 125I-labeled leptin specifically binds to the transformed inhibitor, which arises by reaction with proteinases or with reactive primary amines. No leptin binding was observed to the native alpha2-M, which abundantly occurs in plasma. The complex formation between leptin and alpha2-M was found to proceed within minutes and was stable, as it resisted separation by SEC and electrophoresis. The Kd of the complex was 2.14 +/- 0.78 micromol/l. Complex formation with transformed alpha2-M did not interfere with the immunological determination of leptin in plasma. The leptin-alpha2-M complex was found to be recognized by the alpha2-M receptor/low density lipoprotein receptor-related protein. By computer analysis, a simple model is presented showing that the degree of transformation of alpha2-M may significantly influence the leptin concentration in blood. CONCLUSIONS: The proteinase inhibitor, alpha2-M, may act as a leptin-binding protein in human plasma. Binding of leptin to transformed alpha2-M and its rapid clearance by the alpha2-M receptor may significantly influence the bioavailability of leptin in human plasma.

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Vasconcellos, Marcel, Amabile Maran Carra, Olavo Borges Franco, Wagner Baetas-da-Cruz, Manoel Luiz Ferreira, Paulo Cesar Silva, Sergio Augusto Lopes de Souza, Leandro Miranda-Alves, Denise Pires de Carvalho, and Alberto Schanaider. "Cryopreserved Rat Thyroid Autotransplantation in the Treatment of Postoperative Hypothyroidism." Frontiers in Endocrinology 12 (May 17, 2021). http://dx.doi.org/10.3389/fendo.2021.625173.

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To verify the viability and functionality of cryopreserved thyroid autotransplantation in rats who underwent total thyroidectomy in the treatment of postoperative hypothyroidism. Thirty-two Wistar rats were randomly assigned into groups (G) with eight animals each: control (CG); simulation (SG); hypothyroidism (HTG) and transplanted (TG). At the beginning and in the 13th week of the experiment, serum levels of total T3, free T4, TSH and calcium were determined. In both the first and 14th weeks, scintigraphic examinations, 99m-Tc pertechnetate radioisotope biodistribution and histopathology were performed. In the 14th week, the expression of proliferating cell nuclear antigen (PCNA) and cellular apoptosis (caspase-3) were also evaluated. In the 13th week, the transplanted animals had normal serum levels of total T3 and free T4. TSH levels showed a tendency towards normality. In the 14th week, scintigraphic exams displayed graft isotopic uptake in all animals in the TG group. Histological examinations 13 weeks after transplantation showed the viability and functionality of thyroid follicles. PCNA revealed significant immunoreactivity of the graft (p < 0.001) when the TG was compared to the CG. There was no difference between CG and TG considering the expression of activated caspase-3. The experimental study confirmed the viability and functionality of thyroid autotransplantation implanted in skeletal muscle with evidence of cell proliferation without cellular apoptosis. This surgical strategy was effective in the treatment of postoperative hypothyroidism.

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Journal articles on the topic 'Radioisotopes in endocrinology'

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