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1.
Poult Sci ; 96(5): 1473-1477, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27965406

RESUMO

This study was conducted to determine the effect of in ovo feeding of dextrin (Dext) and iodinated casein (IC) on hatch and early growth in broilers. Three experiments were conducted at a commercial hatchery using a commercial Inovoject™ system with treatments occurring in conjunction with vaccination at transfer from incubator to hatcher units (18.5 to 19 d embryonic development). In all 3 experiments, approximately 15,000 eggs (2,500 eggs per group) were treated and transferred to a single hatcher unit. Treatments in Exp. 1 consisted of buffered saline solution alone (Control, Cont) or a dextrin solution (Dext, 18% maltodextrin, 10% potato starch dextrin) containing zero, 80, 240, 720, or 2,160 µg IC/mL. The results of this initial experiment indicated that broiler chicks at hatch that received 240 and 720 µg IC/mL in Dext were heavier (P < 0.05) compared to the other treatment groups; there were no differences in hatchability between groups. Based on these findings, subsequent studies used treatments of zero, 240, and 480 µg/mL IC in Dext or Cont. In Exp. 2, hatch weights in all treatment groups were higher (P < 0.05) compared to those receiving Cont. In Exp. 3, chicks given Dext alone or 240 and 480 µg/mL in saline weighed less at hatch compared to the other treatment groups. However, chicks provided Dext alone in Exp. 3 had less weight loss after a 24-hour holding period compared to the other groups. All treatment groups exhibited greater weight gain from one to 10 d compared to the Cont group. The results indicate that in ovo feeding of broiler embryos with Dext containing 240 and 480 µg IC/mL may have beneficial effects on broiler hatch weights and early growth rate.


Assuntos
Caseínas/farmacologia , Galinhas/fisiologia , Dextrinas/farmacologia , Iodoproteínas/farmacologia , Polissacarídeos/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Caseínas/administração & dosagem , Embrião de Galinha/efeitos dos fármacos , Galinhas/crescimento & desenvolvimento , Dextrinas/administração & dosagem , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/fisiologia , Iodoproteínas/administração & dosagem , Polissacarídeos/administração & dosagem
2.
Poult Sci ; 96(5): 1478-1484, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27965407

RESUMO

Studies were conducted using a commercial InovojectTM system to determine effects of in ovo feeding of dextrin and iodinated casein (IC) on hatch and posthatch growth in broilers. At ∼18.5 d embryonic development, eggs were treated with 0, 240, or 480 µg IC/mL in saline (Cont, IC240, and IC480) or dextrin (Dext, DextIC240 and DextIC480). The Dext solution consisted of 18% maltodextrin and 10% potato starch dextrin; saline was the vehicle used by the company for in ovo vaccination. The volume for all in ovo treatments was 50 µL/injection. Eggs in Experiment 1 were transferred to a commercial hatcher unit whereas eggs in Experiments 2 and 3 were transferred to a research hatcher unit to assess effects of treatments on timing of hatch. At hatch, chicks were randomly selected and placed in floor pens and grown to 6 wk. In Experiment 1, there were no differences in hatch weights, but broilers provided Dext IC240 in ovo were heavier (P < 0.05) at 6 wk compared to other treatments with the exception of the Dext IC240 group. In Experiment 2, hatch weights were heavier (P < 0.05) in chicks receiving IC240 and DexIC480 treatments compared to Controls. At 6 wk, broilers in all treatments were heavier (P < 0.05) than Cont with the exception of IC480. In Experiment 3, hatch was stimulated by IC240 (in saline), but was delayed by Dext IC240. Serum analysis of ß-hydroxybutyrate (µM/mL), as an indicator of ketone accumulation from fat metabolism of chicks held in chick boxes for 24 h posthatch (to simulate delay in placement after hatch), indicated that chicks in the IC240 group (that hatched earlier) had higher blood ketones compared to chicks that received Dext or DextIC240 in ovo (that hatched later). We conclude dextrin and iodinated casein (240 µg/mL) provided in ovo (∼18.5 d of embryonic development) has the potential to improve chick quality and posthatch body weight by delaying or narrowing hatch window.


Assuntos
Caseínas/administração & dosagem , Caseínas/farmacologia , Galinhas/fisiologia , Dextrinas/farmacologia , Iodoproteínas/administração & dosagem , Iodoproteínas/farmacologia , Polissacarídeos/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Galinhas/crescimento & desenvolvimento , Dextrinas/administração & dosagem , Polissacarídeos/administração & dosagem , Fatores de Tempo
3.
Protein Pept Lett ; 21(10): 1004-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24975669

RESUMO

Suzuki-Miyaura coupling reaction was applied in the syntheses of neoglycopeptides. This work utilizes new type of glycosyl aryl boronic acid and readily accessible iodo amino acids/iodopeptides. Both carbohydrate and peptide moieties are unprotected and the final product could be isolated directly. The neoglyco amino acid and neoglycopeptide products feature an O-glycosyl biaryl linker between the carbohydrate and peptide moieties.


Assuntos
Ácidos Borônicos/química , Glicopeptídeos/síntese química , Iodoproteínas/química , Catálise , Glicosilação , Estrutura Molecular , Paládio/química
4.
Poult Sci ; 89(12): 2646-50, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21076103

RESUMO

Two experiments were conducted with a commercial turkey company using a commercial egg injection system to investigate the effect of a dextrin-iodinated casein solution injected in ovo at 25 d of incubation on turkey poult hatchability, hatch weight, and growth (6 or 7 d posthatch). In experiment 1, a total of 3,900 turkey eggs (1,300 per group) were injected at 25 d of incubation with either 200 µL of a control (physiological saline) solution or a dextrin solution (18% maltodextrin and 10% potato starch dextrin) with 75 or 375 µg/mL of iodinated casein (DexIC75 or DexIC375, where Dex and IC refer to dextrin and iodinated casein, respectively). Two hundred poults from each group were neck-tagged, weighed (hatch weight), placed in a commercial turkey house within a single brooder ring, and weighed again (7 d posthatch). In experiment 2, a total of 5,200 eggs (2,600 per group) were injected with the control or DexIC75 solution. A total of 600 poults (300 per group) were neck-tagged and hatch weights were obtained, followed by placement in a single brooder ring in a commercial house and a second weighing (6 d posthatch). Eggs in experiments 1 and 2 were obtained from hen flocks that were 33 and 5 wk into the laying cycle, respectively. In experiment 1, the DexIC75 injection resulted in a 1.8% increase (P = 0.03) in hatch weight. In experiment 2, the DexIC75 treatment resulted in a 2.4% increase in hatchability (P = 0.01), a 4.3% increase in hatch weight (P < 0.001), and a 1.8% increase in 6-d poult weights (P < 0.03) compared with controls. Results of this study indicate that a solution containing dextrin and 75 µg/mL of iodinated casein injected into turkey eggs at 25 d of incubation may be used to improve early poult weights, hatchability, or both in commercial turkey production.


Assuntos
Caseínas/farmacologia , Ovos/análise , Iodoproteínas/farmacologia , Perus/fisiologia , Animais , Peso Corporal , Caseínas/administração & dosagem , Relação Dose-Resposta a Droga , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/fisiologia , Feminino , Gentamicinas/farmacologia , Iodoproteínas/administração & dosagem , Maltose/farmacologia , Projetos Piloto , Polissacarídeos/farmacologia , Perus/crescimento & desenvolvimento
5.
J Chromatogr B Analyt Technol Biomed Life Sci ; 877(32): 4175-9, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19939749

RESUMO

A new and simple HPLC-MS method was developed for monitoring iodinated casein in feed premixes. In this method, feed premixes were hydrolyzed, and the iodotyrosines thus released were analyzed. Sample pretreatment included precipitation of transition metals ions with Na(2)S, hydrolysis with sodium hydroxide, and cleaning up with an Oasis SAX cartridge. Gradient elution was carried out on a C(18) column with water (containing 0.1% formic acid) and acetonitrile. Ion detection was performed using ESI positive SIM at m/z 262, 308, 388, and 434. Iodinated casein levels were monitored by qualitative analysis of the iodotyrosines released upon sample hydrolysis and by quantifying the 3,5-diiodotyrosine released. The validation data demonstrated that the method was selective and sensitive (

Assuntos
Ração Animal/análise , Caseínas/análise , Cromatografia Líquida de Alta Pressão/métodos , Iodoproteínas/análise , Monoiodotirosina/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia Líquida de Alta Pressão/economia , Hidrólise , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/economia
6.
Org Lett ; 10(15): 3243-5, 2008 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-18598051

RESUMO

An efficient arylation in water of tyrosine and phenylalanine side chains from unprotected iodopeptides is accomplished by using Suzuki-Miyaura cross-coupling processes. The method is compatible with the hydrophilic and thermolabile nature of biologically active peptides. Also of interest, the arylated tyrosine peptides can be accessed in one-pot mode starting from native peptides.


Assuntos
Iodoproteínas/química , Peptídeos/síntese química , Fenilalanina/química , Tirosina/química , Encefalina Leucina/química , Oniocompostos/química , Peptídeos/química , Piridinas/química
7.
Vopr Pitan ; 74(4): 3-8, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16265907

RESUMO

Iodine is an essential trace element, its deficiency leads to iodine-deficient diseases. Utilization of iodinated milk proteins in human diet seems to be one of possible decisions of the problem. The aim of the present work was to characterize iodinated milk proteins "Bioiod", produced by the original technology of "SPF Technovita". The presence of iodinated amino acids (mono- and di-iodotyrosine) was proved by iodinated proteins hydrolyzates HPLC--MALDI mass-spectrometry was used for the determination of iodinated proteins. The percentage of iodine incorporated into proteins was proved to be more then 2%.


Assuntos
Iodo/deficiência , Iodoproteínas , Proteínas do Leite , Aminoácidos/análise , Cromatografia Líquida de Alta Pressão , Humanos , Hidrólise , Iodetos/análise , Iodo/análise , Iodoproteínas/administração & dosagem , Iodoproteínas/análise , Espectrometria de Massas , Proteínas do Leite/administração & dosagem , Proteínas do Leite/análise
8.
J Toxicol Sci ; 29(2): 137-45, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15206582

RESUMO

We hypothesize that iodine allergy is an immune response to iodinated autologous proteins generated in vivo from iodine-containing organic and inorganic chemicals. In this report, effects of protein iodination on elicitogenic activity in guinea pig iodine allergy model and iodinated protein antigen generation in vitro from iodine-containing chemicals were investigated. Active cutaneous anaphylaxis (ACA) and delayed-type hypersensitivity (DTH) tests were performed in guinea pigs immunized with iodine. The amount of iodine (I2) reacted to proteins for giving them an eliciting activity of ACA was > or = 0.15 micromol for 1 mg of albumin. DTH reactions were provoked by intradermal injection of 10(6) PECs reacted with > or = 0.075 micromol of I2. I2 was generated from a potassium iodide (KI) solution or iodinated contrast media by UV light irradiation. X-ray irradiation of KI and iodinated contrast media in the presence of protein resulted in the generation of iodinated protein antigens. The generation of iodinated protein antigens was inhibited in the presence of reducing agents. Therefore, it is noteworthy that iodine allergy of the present hypothesis is dependent on reactive oxygens. By presenting these ex vivo and in vitro data, we discuss the possibilities for the generation of iodinated protein antigens in vivo.


Assuntos
Meios de Contraste , Hipersensibilidade a Drogas/etiologia , Imunização , Iodoproteínas/imunologia , Iodeto de Potássio , Transferência Adotiva , Albuminas/química , Animais , Antígenos/imunologia , Antioxidantes/farmacologia , Líquido Ascítico/citologia , Líquido Ascítico/imunologia , Líquido Ascítico/metabolismo , Meios de Contraste/efeitos adversos , Meios de Contraste/química , Meios de Contraste/efeitos da radiação , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Ensaio de Imunoadsorção Enzimática , Feminino , Cobaias , Hipersensibilidade Tardia/imunologia , Iodoproteínas/síntese química , Iodoproteínas/farmacologia , Iohexol/efeitos adversos , Iohexol/química , Iohexol/efeitos da radiação , Ácido Iotalâmico/efeitos adversos , Ácido Iotalâmico/química , Ácido Iotalâmico/efeitos da radiação , Anafilaxia Cutânea Passiva/efeitos dos fármacos , Anafilaxia Cutânea Passiva/imunologia , Iodeto de Potássio/efeitos adversos , Iodeto de Potássio/imunologia , Iodeto de Potássio/efeitos da radiação , Raios Ultravioleta , Raios X
9.
J Toxicol Sci ; 29(2): 147-54, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15206583

RESUMO

We hypothesize that iodine allergy is an immune response to iodinated self proteins produced in vivo from various iodine-containing chemicals. Since an antigenic determinant of experimental iodine allergy is diiodotyrosine (DIT), we designed low molecular weight DIT derivatives having provocative antigenicity without sensitizing immunogenicity. Tetraiododityrosine and hexaiodotrityrosine provoked dose-dependent skin reactions in guinea pigs previously immunized with iodine. No guinea pigs immunized with hexaiodotrityrosine showed anaphylactic reaction by i.v. challenge with hexaiodotrityrosine and none of their antisera showed positive passive cutaneous anaphylaxis (PCA) reaction in guinea pigs, indicating the non-immunogenic nature of the compound. Erythrosine, one of the color additives having a structure common with DIT, was assessed for its immunological property. Enzyme-linked immunosorbent assay (ELISA) inhibition studies on erythrosine revealed that the inhibitory activity of erythrosine was stronger than that of DIT. Furthermore, erythrosine provoked a PCA reaction in animals sensitized with anti-iodine antisera. In conclusion, hexaiodotrityrosine is thought to be useful for skin testing of iodine allergy without any fear of sensitization to the allergen. Erythrosine was shown to provoke an experimental iodine allergy and, also, the relationships between the new concept of iodine allergy and features of clinical findings of adverse effects by iodocontrast media are discussed.


Assuntos
Meios de Contraste/efeitos adversos , Di-Iodotirosina/análogos & derivados , Hipersensibilidade a Drogas/etiologia , Eritrosina/efeitos adversos , Imunização , Iodeto de Potássio , Animais , Di-Iodotirosina/química , Di-Iodotirosina/imunologia , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Corantes Fluorescentes/efeitos adversos , Cobaias , Iodoproteínas/química , Iodoproteínas/imunologia , Peso Molecular , Anafilaxia Cutânea Passiva , Iodeto de Potássio/efeitos adversos , Iodeto de Potássio/imunologia
10.
Eur J Endocrinol ; 149(4): 247-56, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14514339

RESUMO

The thyroid gland is the only source of thyroid hormone production. Thyroid hormone is essential for growth and development, and is of special importance for the development of the central nervous system. It was for that reason that neonatal screening on congenital hypothyroidism was introduced and is now performed in many countries. Defects in thyroid hormone production are caused by several disorders in hormone synthesis and in the development of the thyroid gland (primary hypothyroidism) or of the pituitary gland and hypothalamus (central hypothyroidism). This paper describes defects in the synthesis of thyroid hormone caused by disorders in the synthesis or iodination of thyroglobulin, leakage of iodinated proteins by a stimulated thyroid gland and the presence of abnormal iodoproteins, mainly iodinated albumin, in the thyroid gland and blood circulation. Circulating thyroglobulin and abnormal iodoproteins, as well as the breakdown products of these iodoproteins excreted in urine, are used for etiological diagnosis and classification. Moreover, our finding of an enzyme that catalyses the dehalogenation of iodotyrosines, which is important for iodine recycling and required for economical use of iodine, is also referred to.


Assuntos
Hipotireoidismo Congênito , Iodo/metabolismo , Animais , Humanos , Hipotireoidismo/genética , Iodetos/metabolismo , Iodoproteínas/metabolismo , Mutação , Tireoglobulina/biossíntese , Glândula Tireoide/metabolismo , Hormônios Tireóideos/biossíntese , Hormônios Tireóideos/genética , Tirosina/metabolismo
11.
Voen Med Zh ; 324(5): 37-40, 80, 2003 May.
Artigo em Russo | MEDLINE | ID: mdl-12908402

RESUMO

To evaluate the efficiency of iodcasein in prophylaxis of iodine-deficient states in servicemen the following parameters were studied: iodine sufficiency determined by ioduria median; thyroid volume measured on the base of US data; functional state of hypothalamo-pituitary-thyroid system evaluated by blood level of thyroid hormone and free thyroxin; physical performance assessed by veloergometric test, auto-and-verbal memory and attention change-over. Iodine deficiency was initially detected in 88.9% (main group) and in 94.4% (control group). Ioduria median corresponded to iodine deficit of middle severity in both groups. After the initial examination the persons from the main group were given iodized bread during 9 months. The monitoring results have confirmed the efficiency of iodine prophylaxis with the use iodcasein.


Assuntos
Caseínas/administração & dosagem , Deficiências Nutricionais/prevenção & controle , Iodo/deficiência , Iodoproteínas/administração & dosagem , Militares , Adulto , Pão , Alimentos Fortificados , Humanos , Iodo/urina , Glândula Tireoide/efeitos dos fármacos
12.
Mol Cell Endocrinol ; 213(1): 99-108, 2003 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-15062578

RESUMO

This study shows that organification of radioiodide into proteins of thyroid cancer cells exogenously co-expressing the thyroid peroxidase (TPO) and the sodium/iodide symporter (NIS) is independent of NIS function. When administering (125) I to cells constitutively expressing either NIS, or TPO or NIS/TPO, next to iodide accumulation due to NIS activity, organification was exclusively observed in TPO expressing/co-expressing cells. The use of specific inhibitors for TPO and NIS showed that organification is strictly dependent of TPO and not of NIS. An identical pattern of iodoproteins migrating between approximately 75 and 200 kDa in all cell lines tested was observed. Among the five major iodoproteins, two polypeptides appear to be related and three are most probably unrelated, according to their peptide pattern. Our results significantly indicate that co-expression of TPO in NIS transfected cells mediates iodination on the one hand but on the other hand does not contribute to augmentation of a putative NIS-based radioiodide concentrator gene therapy.


Assuntos
Autoantígenos/metabolismo , Iodeto Peroxidase/metabolismo , Iodo/metabolismo , Iodoproteínas/biossíntese , Proteínas de Ligação ao Ferro/metabolismo , Proteínas/metabolismo , Simportadores/metabolismo , Autoantígenos/genética , Autorradiografia , Linhagem Celular Tumoral , Humanos , Peróxido de Hidrogênio/farmacologia , Iodeto Peroxidase/genética , Radioisótopos do Iodo , Iodoproteínas/análise , Proteínas de Ligação ao Ferro/genética , Simportadores/genética , Neoplasias da Glândula Tireoide/patologia , Transfecção
13.
Am J Med Sci ; 320(2): 148-50, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10981492

RESUMO

We report the case of a 52-year-old woman with recent diagnosis of acute myocarditis and pericarditis, admitted for fever, tachycardia, and dyspnea upon exertion. Hematochemical parameters and instrumental examinations suggested iatrogenic hyperthyroidism and secondary dilated cardiomyopathy. Although gathering information about the medication used at home was initially difficult because of the patient's refusal to cooperate, she ended up by disclosing the regular assumption of an iodocasein drug. A complete and stable regression of the clinical picture was reached by suspending the iodine derivative and using cardiovascular drugs.


Assuntos
Cardiomiopatia Dilatada/etiologia , Caseínas/efeitos adversos , Hipertireoidismo/induzido quimicamente , Hipertireoidismo/complicações , Iodoproteínas/efeitos adversos , Miocardite/induzido quimicamente , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/terapia , Depressão/complicações , Depressão/diagnóstico , Ecocardiografia , Eletrocardiografia , Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Feminino , Humanos , Hipertireoidismo/diagnóstico , Pessoa de Meia-Idade , Miocardite/diagnóstico , Miocardite/terapia , Cintilografia , Glândula Tireoide/diagnóstico por imagem
14.
J Nucl Med ; 40(10): 1716-21, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10520714

RESUMO

UNLABELLED: Radioiodine-131 is used in differentiated thyroid cancer (DTC) for ablation of postsurgical thyroid remnants and destruction of metastases. The question may be raised of whether 131I treatment of DTC in male patients may give an irradiation dose to the testes that could impair fertility. Few data in the literature concern the dose absorbed by the testes after 1311 therapy for DTC. Because 131I kinetics may be altered by the hypothyroid condition commonly present at the time of treatment and by the radioiodinated iodoproteins released by the damaged thyroid tissue, the dose values reported in the International Commission on Radiological Protection (ICRP) tables for euthyroid men may not be appropriate. To clarify this problem, three male subjects undergoing 131I therapy for ablation of thyroid remnants shortly after thyroidectomy for DTC were studied. METHODS: The mean administered activity was 1256 MBq, and the duration of the study was 2 wk. The gamma dose was measured by thermoluminescent dosimeters (TLDs) applied to the lower poles of the testes. Correction factors were calculated for the distance of the TLD from the center of the testes and for attenuation by the testes of the gamma rays reaching the TLD. After correction, the gamma dose to the testes ranged from 21 to 29 mGy. The gamma dose calculated by the Medical Internal Radiation Dose (MIRD) method from blood and urine samples was similar (18-20 mGy) to that measured by TLDs. The beta dose was estimated by the MIRD method from blood activity and testicular volume and ranged between 14 and 31 mGy. RESULTS: The total (beta and gamma) doses to testes were 30, 33 and 43 microGy/MBq in the three subjects. CONCLUSION: These values are close to those derived from the ICRP tables (26-37 microGy/MBq 131I) for euthyroid subjects. The present data indicate that significant irradiation is delivered to the testes after the administration of the 131I ablative dose to thyroidectomized patients. The relevance of the radiation absorbed by testes on fertility remains to be established.


Assuntos
Radioisótopos do Iodo/uso terapêutico , Testículo/efeitos da radiação , Neoplasias da Glândula Tireoide/radioterapia , Administração Oral , Adulto , Terapia Combinada , Fertilidade/efeitos da radiação , Humanos , Radioisótopos do Iodo/sangue , Radioisótopos do Iodo/urina , Iodoproteínas/sangue , Masculino , Neoplasia Residual , Dosagem Radioterapêutica , Dosimetria Termoluminescente , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Fatores de Tempo
15.
Clin Chim Acta ; 275(1): 71-80, 1998 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-9706845

RESUMO

A method has been developed to determine plasma volume with dextran-70 without the use of a fluorescent label. The results obtained are compared to those found using the 125I-labeled albumin method, which is taken as the gold standard. The CV of the method is about 5%, compared to 3% with the gold standard. It is shown to be of use for the determination of an increase in plasma volume during pregnancy.


Assuntos
Dextranos , Iodoproteínas , Volume Plasmático , Albumina Sérica , Feminino , Glucose , Humanos , Técnicas de Diluição do Indicador , Radioisótopos do Iodo , Gravidez , Sensibilidade e Especificidade , Leveduras
17.
Endocrinology ; 135(4): 1566-75, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7925119

RESUMO

The thyroid gland is known to generate the iodinated hormones T3 and T4 from the prohormone thyroglobulin. In this report we examined whether polypeptides other than thyroglobulin are iodinated and hormonogenic in thyrocytes and the prerequisites for their iodination. In primary cultures of porcine thyrocytes, a substantial portion of organified radioiodine was incorporated into cellular proteins other than thyroglobulin. Some of these were identified by immunoprecipitation. They included proteins of the extracellular matrix, plasma membrane proteins, and lysosomal enzymes, which follow in part a secretion and recapture pathway. All of these proteins come into contact with the iodinating system of thyrocytes located on the apical plasma membrane and possess iodination consensus sequences. Immunoprecipitation with T3- or T4-specific antibodies showed that thyroid hormones were detectable only within thyroglobulin. This was confirmed by an analysis of the iodoamino acids of thyroglobulin, cathepsin-D (representing a secretory protein), and aminopeptidase-N (a membrane-integrated protein) by two-dimensional TLC, which revealed the presence of T3 and T4 only within the polypeptide chain of thyroglobulin. These results indicate that iodoproteins other than thyroglobulin do not participate in the generation of thyroid hormones in situ.


Assuntos
Iodoproteínas/análise , Iodoproteínas/fisiologia , Proteínas de Membrana/análise , Proteínas de Membrana/fisiologia , Glândula Tireoide/química , Glândula Tireoide/citologia , Hormônios Tireóideos/metabolismo , Anticorpos/análise , Anticorpos/imunologia , Western Blotting , Catepsina D/fisiologia , Células Cultivadas , Cromatografia em Camada Delgada , Imunofluorescência , Antígenos de Histocompatibilidade Classe II/análise , Antígenos de Histocompatibilidade Classe II/metabolismo , Antígenos de Histocompatibilidade Classe II/fisiologia , Humanos , Iodoproteínas/metabolismo , Medições Luminescentes , Proteínas de Membrana/metabolismo , Octoxinol , Testes de Precipitina , Saponinas , Tireoglobulina/análise , Tireoglobulina/metabolismo , Tireoglobulina/fisiologia , Glândula Tireoide/metabolismo , Hormônios Tireóideos/análise , Hormônios Tireóideos/imunologia
18.
South Med J ; 86(4): 457-60, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8465227

RESUMO

For 30 years we have followed the case of a euthyroid patient who had a goiter diagnosed at age 15. It was originally diffuse and did not shrink during treatment, first with desiccated thyroid extract and then with triiodothyronine. After treatment was stopped, the goiter gradually became nodular and calcified when the patient was in her late teens or early 20s; it then shrank. She remains clinically and chemically euthyroid, with a calcified, multinodular goiter and persistent elevation of the serum PBI concentration which, early in the course of the disease was shown to include a substantial fraction of butanol-insoluble iodine. In a euthyroid patient, the association of an elevated serum PBI concentration (with an abnormally large butanol-insoluble iodine fraction) with a diffuse goiter that became nodular and calcified may be unique.


Assuntos
Calcinose/sangue , Bócio/sangue , Iodoproteínas/sangue , Adolescente , Feminino , Seguimentos , Humanos , Hormônios Tireóideos/biossíntese
19.
Thyroid ; 2(4): 329-35, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1493376

RESUMO

Previously we described sedimentation and immunologic abnormalities of thyroglobulin (Tg) in a strain of mice with inherited congenital goiter and hypothyroidism (cog/cog). The goals of the present study were to determine the extent to which thyroid gland stimulation by TSH accounts for the abnormal properties of cog/cog Tg and to characterize further the abnormally small iodoproteins found in cog/cog mice. Cog/cog and control +/cog and BALB/c mice were fed with either normal or thyroid-hormone-containing diets and were injected with Na125I. Sucrose density gradient centrifugation of labeled thyroid extracts from cog/cog mice on normal diet showed that 82% of the iodine was in iodoproteins smaller than Tg, with sedimentation rates of 3-8S. No 12S and 19S peaks, characteristic of normal Tg, were present, but distinct and stable 12S and 19S peaks emerged after recentrifugation of the 12S and 19S areas. In contrast, in cog/cog mice treated with T4, a smaller (55%) amount of 3-8S iodoproteins and distinct 12S and 19S peaks were present. In both groups of mice, the labeled 3-8S iodoproteins were composed of three fractions: 15% precipitated by antirat Tg serum, 38% precipitated by antimouse albumin serum, and 47% not precipitated by either serum. The 3-8S iodoproteins contained labeled MIT and DIT and no T4. On sodium dodecyl sulfate polyacrylamide gel electrophoresis the 3-8S iodoprotein fraction that reacted with anti-Tg serum contained a distinct electrophoretic band at 49K. The 3-8S nonreactive iodoproteins resolved into several bands of lower molecular weight. We conclude that the 3-8S iodoproteins in cog/cog mice are heterogeneous and that TSH stimulation contributes to the production of these low-molecular-weight iodoproteins.


Assuntos
Bócio/congênito , Iodoproteínas/metabolismo , Tireoglobulina/metabolismo , Aminoácidos/análise , Animais , Centrifugação com Gradiente de Concentração , Eletroforese em Gel de Poliacrilamida , Bócio/metabolismo , Hipotireoidismo/metabolismo , Soros Imunes , Técnicas de Imunoadsorção , Radioisótopos do Iodo , Iodoproteínas/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Mutantes , Peso Molecular , Ratos , Albumina Sérica/imunologia , Tireoglobulina/química , Tireoglobulina/imunologia , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Tireotropina/farmacologia
20.
Cell Tissue Res ; 265(2): 275-85, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1934028

RESUMO

This study attempts to elucidate the mechanism through which lysosomal accumulation occurs with age in the epithelial cells of the thyroid gland and especially in the "active" follicles of the aging mouse thyroid. Thyroid morphology and function in old CBA (at least 24 months of age) male mice were compared with those in young (2 months of age) animals. The effects of different intake of iodine were tested and compared in both cohorts, each of which was divided into three groups: (i) low iodine group, (ii) moderate iodine group, and (iii) high iodine group. As expected, the present work confirmed the well-known accumulation with age of "cold" follicles coexisting with "active" follicles in the old mouse thyroid. Attention has been focused on the active follicles whose follicular cells contained in their cytoplasm a large number of pleomorphic dense bodies. The lysosomal nature of these bodies, referred to as secondary lysosomes, was confirmed by histochemistry; however, they displayed variability in acid phosphatase staining. In old animals, regardless of the type of iodine regimen, the ratio between relative follicular volume and relative colloid volume as determined by morphometry remained unchanged. Ultrastructurally, the relative volume occupied by secondary lysosomes in "active" follicles was always higher than in the young groups. Autoradiographic studies with 125I revealed that a large part of the radioactivity was located in secondary lysosomes of thyroid cells in "active" follicles of old mice when radioiodine was injected 3 weeks before death. Two different types of vacuoles were present in a non-negligible number of thyrocytes of the "active" follicles in aged cohorts. The first type was made up of grossly dilated rough endoplasmic cisternae, the second corresponded to intracytoplasmic microfollicular vacuoles. Both aspects have been described in conditions of chronic stimulation. It is concluded (1) that different intake of iodine for 6 weeks does not modulate the thyroid morphology in old mice; (2) that in the thyrocytes of the "active" follicles in old mice accumulation of secondary lysosomes occurs due to a slowdown of turnover; and (3) that the follicular cells of "active" follicles feature morphological aspects suggesting a hyperactive state compensating the lack of hormone production in the "cold" follicles.


Assuntos
Envelhecimento/patologia , Lisossomos/ultraestrutura , Glândula Tireoide/ultraestrutura , Animais , Coloides , Iodoproteínas/metabolismo , Lisossomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos CBA , Microscopia Eletrônica , Glândula Tireoide/metabolismo , Vacúolos/ultraestrutura
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