Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
J Endocrinol Invest ; 44(8): 1719-1726, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33367977

RESUMO

PURPOSE: Immunotherapy against immune checkpoints has significantly improved survival both in metastatic and adjuvant setting in several types of cancers. Thyroid dysfunction is the most common endocrine adverse event reported. Patients who are at risk of developing thyroid dysfunction remain to be defined. We aimed to identify predictive factors for the development of thyroid dysfunction during immunotherapy. METHODS: This is a retrospective study including a total of 68 patients who were treated with immune checkpoint inhibitors (ICIs) for metastatic or unresectable advanced cancers. The majority of patients were treated with anti-PD1 drugs in monotherapy or in combination with anti-CTLA4 inhibitors. Thyroid function and anti-thyroid antibodies, before starting immunotherapy and during treatment, were evaluated. Thyroid ultrasound was also performed in a subgroup of patients at the time of enrolment in the study. RESULTS: Eleven out of 68 patients (16.1%) developed immune-related overt thyroid dysfunction. By ROC curve analysis, we found that a serum TSH cut-off of 1.72 mUI/l, at baseline, had a good diagnostic accuracy in identifying patients without overt thyroid dysfunction (NPV = 100%, p = 0.0029). At multivariate analysis, both TSH and positive anti-thyroid antibodies (ATAbs) levels, before ICIs treatment, were independently associated with the development of overt thyroid dysfunction during immunotherapy (p = 0.0001 and p = 0.009, respectively). CONCLUSIONS: Pre-treatment serum TSH and ATAbs levels may help to identify patients at high risk for primary thyroid dysfunction. Our study suggests guidance for an appropriate timely screening and for a tailored management of thyroid dysfunctions in patients treated with ICIs.


Assuntos
Inibidores de Checkpoint Imunológico , Imunoterapia/efeitos adversos , Neoplasias , Doenças da Glândula Tireoide , Autoanticorpos/sangue , Antígeno CTLA-4/antagonistas & inibidores , Feminino , Humanos , Inibidores de Checkpoint Imunológico/administração & dosagem , Inibidores de Checkpoint Imunológico/efeitos adversos , Imunoterapia/métodos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/patologia , Neoplasias/terapia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Estudos Retrospectivos , Medição de Risco/métodos , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/etiologia , Doenças da Glândula Tireoide/imunologia , Testes de Função Tireóidea/métodos , Testes de Função Tireóidea/estatística & dados numéricos , Tireotropina/sangue
2.
J Endocrinol Invest ; 42(10): 1205-1213, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30927240

RESUMO

PURPOSE: An increased aggressiveness of familial papillary thyroid carcinoma (FPTC) compared with sporadic form has been reported. On the contrary, the biological behavior of familial microPTC (FmPTC) is still debated. To assess if familial diseases should be considered as a negative prognostic factor in mPTC, the clinical presentation and outcome of FmPTC and sporadic mPTC (SmPTC) were compared. METHODS: We retrospectively analyzed 291 mPTC (SmPTC n = 248, FmPTC n = 43) patients followed for a median follow-up of 8.3 years. FmPTC was defined as the presence of PTC in two or more first-degree relatives, after excluding hereditary syndromes associated with PTC. RESULTS: FmPTC patients had more frequently bilateral tumor (32.6% versus 16.5%, p = 0.01) and lymph node metastases at diagnosis (30.2% versus 14.9%, p = 0.02). At the first follow-up, FmPTC patients had a higher rate of structural disease and a lower rate of remission compared to SmPTC (p = 0.01). Also in a multivariate model, using a "CHAID tree-building algorithm", familial disease correlated with a worse clinical presentation and outcome of mPTC patients. Familial disease was associated with a higher rate of intermediate risk patients in non incidental mPTC and with a higher rate of structural incomplete response in mPTC without lymph node metastases (p = 0.01). CONCLUSIONS: Like in macroPTC, the familial form of the diseases has been shown to be a negative prognostic factor also in mPTC, therefore, it should be highly regarded in the management of mPTC patients.


Assuntos
Câncer Papilífero da Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Anamnese/estatística & dados numéricos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Câncer Papilífero da Tireoide/epidemiologia , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/patologia , Carga Tumoral , Adulto Jovem
3.
J Endocrinol Invest ; 42(6): 693-698, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30406929

RESUMO

BACKGROUND: Prolactin may exert immunological effects. Over the years, a higher prevalence of autoimmune thyroid diseases (ATD) has been reported in patients with prolactinomas (PRLs) in areas with sufficient iodine intake. PURPOSE: The aim of our study was to evaluate the prevalence of ATD [Graves' disease (GD) and chronic autoimmune thyroiditis (AIT)] in a retrospective cohort of Italian patients with PRLs compared to a sex-matched control group, represented by subjects with non-functioning pituitary adenoma (NFPA) or empty sella (ES). MATERIALS AND METHODS: We enrolled 149 patients (108 F/41 M) with PRLs (110 micro/39 macro) and 143 subjects (100 F/43 M) with NFPA (n = 96, 56 micro/40 macro) or ES (n = 47), with normal serum prolactin. Neck ultrasound and thyroid function tests (anti-thyroid antibodies, TSH, FT3 and FT4) were performed in all patients. RESULTS: In PRLs, median serum prolactin was significantly higher (98.3 vs. 8.9 ng/ml, p ≤ 0.0001), while age was lower (34 vs. 46 years, p ≤ 0.001) compared to controls. The prevalence of ATD was 13.4% (20/149) in PRLs (1 GD and 19 AIT) compared to 6.3% (9/143) in the controls (p = 0.042). At the multivariate analysis, serum prolactin was the only independent factor predicting ATD. Thyroid volume (12.5 ± 5.9 ml vs. 12.8 ± 10 ml, p = 0.47) and the presence of uni- or multinodular goiter (29.5% vs. 35%, p = 0.35) did not differ between PRLs and control groups. CONCLUSIONS: Our data in an area with mild iodine deficiency confirm a higher prevalence of ATD in patients with prolactinomas.


Assuntos
Prolactinoma/fisiopatologia , Doenças da Glândula Tireoide/epidemiologia , Tireoidite Autoimune/epidemiologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Estudos Retrospectivos , Testes de Função Tireóidea , Adulto Jovem
4.
Braz J Microbiol ; 39(4): 631-5, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24031279

RESUMO

In the last decades, coagulase-negative staphylococci (CoNS), especially Staphylococcus epidermidis have become an important cause of bloodstream infections. In addition, rates of methicillin-resistance among CoNS have increased substantially, leading to the use of glicopeptides for therapy. The objective of this study was to evaluate eleven consecutives clinically relevant cases of oxacillin-resistant CoNS bacteremia in a general hospital localized in São Paulo city, Brazil. Five different species were identified by different phenotypic methods, including S. epidermidis (5), S. haemolyticus (3), S. hominis (1), S. warneri (1) and S. cohnii subsp urealyticus (1). A variety of Pulsed Field Gel Electrophoresis profiles was observed by macrorestriction DNA analysis in S. epidermidis isolates, but two of three S. haemolyticus isolates presented the same profile. These data indicated the heterogeneity of the CoNS isolates, suggesting that horizontal dissemination of these microorganisms in the investigated hospital was not frequent. One S. epidermidis and one S. haemolyticus isolates were resistant to teicoplanin and susceptible to vancomycin. The selective pressure due to the use of teicoplanin in this hospital is relevant.

5.
Vet Immunol Immunopathol ; 115(1-2): 1-9, 2007 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17109971

RESUMO

Heterophile antibodies (HAs) present in serum recognize animal immunoglobulins and are one of the most unpredictable causes of false results in immunoassays. However, no study has yet reported their interference on the diagnostic reliability of immunochemical analyses on horse plasma. Recently, we developed a sandwich ELISA for detection of equine growth hormone (eGH) in plasma. In a pilot study to measure basal eGH levels (blood samples were drawn from 13 horses every 10 min for 1h), we noted one horse with abnormally high eGH (>100 ng/mL). We demonstrate here that this plasma eGH level was falsely elevated due to interference from HAs. The interfering antibodies were polyspecific immunoglobulins, with fairly broad species-specificity, which affected the eGH immunoassay by bridging the mouse IgG capture antibody and the rabbit IgG conjugate. This produced artificial sandwiches which led to overestimation of the eGH plasma concentration. Spiking horse plasma with pure mouse and rabbit immunoglobulins or whole plasma of several species significantly reduced but did not totally eliminate the HAs interference. Immunoglobulins and whole plasma differed in their ability to block the interference, suggesting that HAs may recognize other proteins beside immunoglobulins in animal sera. To investigate whether HAs have any implications in equine clinical practice, we decided to seek information on the incidence of HAs interference in normal animals. We collected single plasma samples from another 114 horses and we found that 5 of these had plasma HAs. Therefore, in total 6 out of the 127 horses examined (4.7%) had plasma HAs generating falsely elevated eGH measures. In conclusion, this study provides the first evidence of HAs in horse plasma interfering with an immunoassay and indicates that veterinary surgeons and diagnostic laboratory staff should be aware of this potential for interference in tests on horse plasma using monoclonal or polyclonal antibody reagents.


Assuntos
Anticorpos Heterófilos/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Hormônio do Crescimento/sangue , Animais , Cães , Feminino , Cavalos , Masculino , Camundongos , Coelhos
6.
Eur J Histochem ; 51(3): 173-80, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17921112

RESUMO

In the last few years, several works suggest that Growth Hormone (GH) is involved in follicular development and oocyte maturation. These actions may reflect endocrine roles of pituitary GH and also account for local autocrine or paracrine activities of GH produced in reproductive tissue. This study was aimed to verify whether the developmental competence of bovine female gametes might be related to ovarian GH. We evaluated the localisation and distribution of GH in the cumulus oocytes complexes (COCs) and the concentration of GH in the oocytes and in the follicular fluids (FF) from ovaries classified on the basis of the follicles number. Oocytes retrieved from ovaries with more than 10 follicles of 2 to 5 mm in diameter (High ovaries, Hi) show higher rate of maturation and blastocyst formation than those retrieved from ovaries with less than 10 follicles (Low ovaries, Lo). At the same time we measured Estrogen (E2) and Progesterone (P4) concentrations in FF, to relate oocytes quality, GH concentration and follicle health. GH localization in COCs and oocytes was performed by indirect immunofluorescence and its concentration within the ooplasm was evaluated by microspectrophotometer analysis. GH, E2 and P4 concentrations in FF were measured by an Enzyme Linked ImmunoSorbent assay (ELISA). We observed a positive, diffuse signal at cytoplasmic level in most of the cumulus cells, with no differences between COCs collected from Hi and Lo ovaries. On the contrary, GH level was significantly higher in the oocytes collected from Lo ovaries than in those recovered from Hi ovaries. Finally we found that also GH level in the FF was inversely related to the oocytes developmental capability. We suggest that the increase of GH in the oocytes and in the FF derived from Lo ovaries might be interpreted as attempt of the follicular environment to improve ovarian activity and in turn oocytes developmental competence in a autocrine-paracrine manner. Moreover, E2, and P4 levels in FF suggest that, in our model, atresia processes are also involved in oocyte developmental capability and that the highest level of GH may represent a local reaction to these phenomena.


Assuntos
Blastocisto/fisiologia , Líquido Folicular/metabolismo , Hormônio do Crescimento/metabolismo , Oócitos/fisiologia , Animais , Blastocisto/citologia , Bovinos , Ensaio de Imunoadsorção Enzimática , Estradiol/metabolismo , Feminino , Fertilização in vitro , Imunofluorescência , Oócitos/metabolismo , Folículo Ovariano/citologia , Folículo Ovariano/metabolismo , Progesterona/metabolismo , Técnicas de Cultura de Tecidos
7.
Neuropsychologia ; 43(3): 450-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15707620

RESUMO

The present study aimed to determine whether the bradykinesia of Parkinson's disease (PD) patients during the execution of reaching-grasping movements (i) is related to an impaired implementation of movement parameters and (ii) selectively involves the control of reach and/or grasp movements. We compared the kinematics of reaching to grasp of differently sized objects placed at different positions, among PD patients in the early stage of disease (ESPD), in the advanced stage of disease (ASPD) without L-dopa medication (off-state), and in healthy controls. In addition, we analysed the effects of L-dopa replacement therapy by comparing the kinematics of the patients in the advanced stage of disease after L-dopa administration with those of the other groups. Bradykinesia increased with disease progression, but only in the initial phases of the reach and grasp components. However at both stages of the disease, the kinematics of reaching and grasping responded to extrinsic and intrinsic object properties just as in controls. L-dopa administration improved the performance of PD patients, though this was more evident for the reach than for the grasp. We suggest that the basal ganglia (BG) are involved in implementing kinematic parameters, but neither (or only marginally) in the initial movement parameterization itself, nor in the on-line control of movement. Specifically, the BG dysfunction in PD induces a slowed implementation of movement parameters. The lack of effect of L-dopa administration on grasp kinematics may be because the motor control of distal effectors is less represented in the motor circuitry formed by the supplementary motor area (SMA), thalamus and BG.


Assuntos
Gânglios da Base/fisiologia , Hipocinesia/etiologia , Hipocinesia/fisiopatologia , Doença de Parkinson/complicações , Idoso , Antiparkinsonianos/administração & dosagem , Antiparkinsonianos/farmacologia , Fenômenos Biomecânicos , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Levodopa/administração & dosagem , Levodopa/farmacologia , Masculino , Pessoa de Meia-Idade , Transtornos das Habilidades Motoras/fisiopatologia , Doença de Parkinson/fisiopatologia , Índice de Gravidade de Doença , Análise e Desempenho de Tarefas
8.
J Mol Endocrinol ; 23(3): 307-13, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10601976

RESUMO

We describe the properties of three monoclonal antibodies (MAbs) to ovine GH, two of which have previously been shown to enhance, in vivo, the biological activity of bovine and ovine growth hormone. We have examined the effects of these MAbs on GH activity in two appropriate GH-responsive cell culture systems, investigating both acute signalling effects (Janus-activated kinase (Jak)-2 tyrosine phosphorylation -5 min) and longer-term (MTT-formazan production -24 h) effects of hormone-antibody complexes. In the 3T3-F442A pre-adipocyte cell line (which has been demonstrated to be GH responsive), we show that complexation of recombinant bovine (rb) GH with either of the two enhancing anti-ovine GH MAbs (OA11 and OA15) and the non-enhancing MAb, OA14, attenuates the ability of GH to stimulate tyrosine phosphorylation of Jak-2 at a 5-min time point. Using the mouse myeloid cell line, FDC-P1, stably transfected with the full-length ovine GH receptor (oGHR), we demonstrate that rbGH causes a dose-dependent increase in MTT-formazan production by these cells. Further, we demonstrate that OA11 and OA14, but not OA15, cause a decrease in this stimulatory activity of rbGH over a hormone concentration range of 5-50 ng/ml at both 24 and 48 h. We conclude that the different in vitro activities of the two in vivo enhancing MAbs are most probably related to the time-courses over which these two assays are performed, and also to the relative affinities between antibody, hormone and receptor. In addition, the in vitro inhibitory activity of the enhancing MAb OA11 in both short- and long-term bioassay lends further support to an exclusively in vivo model for MAb-mediated enhancement of GH action.


Assuntos
Anticorpos Monoclonais/farmacologia , Complexo Antígeno-Anticorpo/farmacologia , Hormônio do Crescimento/agonistas , Hormônio do Crescimento/farmacologia , Proteínas Proto-Oncogênicas , Transdução de Sinais/efeitos dos fármacos , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/enzimologia , Adipócitos/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Complexo Antígeno-Anticorpo/imunologia , Sítios de Ligação , Bovinos , Linhagem Celular , Formazans/metabolismo , Hormônio do Crescimento/antagonistas & inibidores , Hormônio do Crescimento/imunologia , Janus Quinase 2 , Camundongos , Fosforilação/efeitos dos fármacos , Fosfotirosina/metabolismo , Prolactina/farmacologia , Proteínas Tirosina Quinases/metabolismo , Ratos , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo , Ovinos , Especificidade por Substrato , Sais de Tetrazólio/metabolismo , Fatores de Tempo , Transfecção
9.
J Immunol Methods ; 136(1): 17-22, 1991 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-1995708

RESUMO

Highly purified pituitary bovine prolactin (bPRL) has been used in a sensitive non-competitive enzyme-linked immunosorbent assay of prolactin (PRL) concentrations in plasma. In this assay affinity purified polyclonal antibodies were immobilized to the solid phase in order to capture the antigen, and were also used biotinylated as the detector antibody. The method was found to be reproducible (3% variability between calibration curves) and has been optimized for measuring bPRL concentration in plasma samples, giving an intra-assay coefficient of variation of about 5% and an interassay coefficient of variation of about 9%. The sensitivity of the assay was found to be as low as 0.1 ng/ml of bPRL.


Assuntos
Ensaio de Imunoadsorção Enzimática , Prolactina/sangue , Animais , Bovinos , Reações Cruzadas , Prolactina/imunologia , Coelhos
10.
J Immunol Methods ; 110(1): 123-8, 1988 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-3373001

RESUMO

Purified pituitary bovine growth hormone (bGH) has been used to develop a homologous sandwich enzyme-linked immunosorbent assay in which affinity-purified antibodies are immobilized on microtiter plates. Bovine GH bound to specific antibody is then revealed with a second anti-bGH antibody labeled with biotin and peroxidase-conjugated avidin. The method requires only 48 h, including the coating step, and has a sensitivity as low as 0.25 ng/ml of bGH. Statistical analyses (test of parallelism, cross-reactivity among bGH and GH of various species and bovine prolactin, recovery test, within- and between-assay variation, comparison with radioimmunoassay) confirm the high specificity and reproducibility of the method.


Assuntos
Bovinos/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Hormônio do Crescimento/sangue , Animais , Avidina , Biotina , Reações Cruzadas , Hormônio do Crescimento/imunologia , Soros Imunes , Mamíferos/imunologia , Especificidade da Espécie
11.
Immunol Lett ; 38(1): 41-5, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8300153

RESUMO

The sequential epitopes on bovine growth hormone (bGH) recognised by five polyclonal mouse antisera have been identified by scanning with multiple pin-bound peptides. Four main epitopes were identified at residues 29-40, 101-110, 139-152 and 181-191. Of these, only epitope 139-152 is recognised by all five mouse antisera indicating that, for the mouse, this may represent an immuno-dominant region of the bGH molecule.


Assuntos
Hormônio do Crescimento/imunologia , Epitopos Imunodominantes/imunologia , Sequência de Aminoácidos , Animais , Bovinos , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Fragmentos de Peptídeos/imunologia , Proteínas Recombinantes/imunologia
12.
J Endocrinol ; 146(2): 271-7, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7561639

RESUMO

Clonidine is a specific alpha-2-adrenoreceptor agonist that stimulates growth hormone (GH) release in animals and humans. This drug was used to study the GH and prolactin (PRL) secretory response in dairy cows and heifers. An i.v. infusion of 10 micrograms/kg body weight induced GH release to a peak concentration after 30-60 min, while 2 micrograms/kg had no effect on GH secretory patterns. Plasma PRL decreased significantly (P < 0.01) starting 15-60 min after both doses of clonidine, this effect lasting up to 6 h. Clonidine significantly lowered plasma insulin (P < 0.01) and raised plasma glucose (P < 0.01). The changes in plasma GH, PRL, insulin and glucose differed significantly between doses, the 10 micrograms/kg dose being more effective (P < 0.01). The results of our investigation in dairy cattle provide evidence of (i) an increase in GH release after 10 micrograms/kg clonidine; (ii) a concomitant decrease in PRL secretion, hence GH and PRL secretion in cattle appear inversely controlled; (iii) a significant difference between the effects of the 2 and 10 micrograms/kg doses and (iv) no relationship between the changes in plasma GH and PRL after clonidine and plasma hormone levels before treatment.


Assuntos
Clonidina/farmacologia , Hormônio do Crescimento/metabolismo , Lactação/fisiologia , Hipófise/efeitos dos fármacos , Prolactina/metabolismo , Animais , Glicemia/metabolismo , Bovinos , Relação Dose-Resposta a Droga , Feminino , Hormônio do Crescimento/sangue , Insulina/sangue , Prolactina/sangue
13.
Clin Chim Acta ; 121(1): 79-86, 1982 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-7083596

RESUMO

In order to develop a gas chromatographic method with flame ionization detection for the analysis of urinary 3-methoxy-4-hydroxyphenylethyleneglycol sulphate, a new procedure for its isolation has been introduced. The conjugated metabolite has been extracted by an ion-pair technique using tetrabutyl ammonium as counter ion and dichloromethane as organic solvent. Hydrolysis and derivatization of 3-methoxy-4-hydroxyphenylethyleneglycol sulphate have been finally performed by treatment with heptafluorobutyric anhydride. Each step of the procedure, applied to the analysis of urine samples both from normal subjects and from patients with neuroblastoma, has been discussed.


Assuntos
Cromatografia Gasosa/métodos , Glicóis/urina , Metoxi-Hidroxifenilglicol/urina , Neuroblastoma/urina , Adulto , Criança , Pré-Escolar , Detergentes , Feminino , Humanos , Masculino , Metoxi-Hidroxifenilglicol/isolamento & purificação , Cloreto de Metileno , Compostos de Amônio Quaternário
14.
Clin Chim Acta ; 94(2): 155-61, 1979 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-378468

RESUMO

3,4-Dihydroxyphenylethyleneglycol, a major metabolite of noradrenaline in rat brain, is estimated alone or with 4-hydroxy-3-methoxyphenylethyleneglycol in rat and human urine by gas chromatography with a flame ionization detector. The samples are hydrolyzed and extracted at pH 2 with ethyl acetate. Then, to analyze only 3,4-dihydroxyphenylethyleneglycol the reaction with n-butaneboronic acid is carried out directly; if 4-hydroxy-3-methoxyphenylethyleneglycol also has to be estimated, preliminary acetylation in alkaline aqueous solution is performed. The advantages of the specificity due to the reagents used is discussed.


Assuntos
Glicóis/urina , Metoxi-Hidroxifenilglicol/urina , 3-Metoxi-4-Hidroxifeniletanol/urina , Animais , Cromatografia Gasosa/métodos , Humanos , Indicadores e Reagentes , Metoxi-Hidroxifenilglicol/análogos & derivados , Ratos
16.
J Biochem Biophys Methods ; 1(1): 45-57, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-551975

RESUMO

Human globin chain separation, a key procedure in the study of hemoglobinopathies, is routinely performed by chromatography on carboxymethylcellulose. This method, though relatively easy and highly reliable, is expensive and time consuming. A new procedure, based on isoelectric focusing, is presented which allows the simultaneous separation of globin chains from multiple samples (at least 20 per gel slab). The method is rapid, inexpensive and can be easily carried out in clinical laboratories, and its high sensitivity allows the identification of radioactive bands even with minute amounts of labelled material. A new phenomenon, called the 'Nonidet P-40 effect', which greatly enhances the separation between gamma and beta chains by binding to these two chains and shifting their pI values in opposite directions, is described.


Assuntos
Globinas/isolamento & purificação , Cromatografia por Troca Iônica/métodos , Humanos , Focalização Isoelétrica/métodos , Substâncias Macromoleculares , Talassemia/sangue
17.
Ital J Biochem ; 30(2): 117-26, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7263186

RESUMO

The isolation and purification of bovine growth hormone from pituitary glands by a shorter and efficient sequence of stages which utilizes the Reichert approach (Reichert, 1975) is described. The major innovations are: 1) precipitation in 2 M ammonium sulfate at pH 7.9 instead of pH 7.0 to obtain the extract designated as C-2 by Reichert and 2) early gel-chromatography on Sephacryl S-200 of the C-2 extract. The bGH obtained has higher specific activity than the standard reference hormone NIH-GH-B16. Electrophoretic and size homogeneity is investigated by isoelectric focusing and sodium dodecyl sulfate electrophoresis.


Assuntos
Resinas Acrílicas , Hormônio do Crescimento/isolamento & purificação , Animais , Bovinos , Cromatografia em Gel/métodos , Eletroforese em Gel de Poliacrilamida , Focalização Isoelétrica
18.
Theriogenology ; 46(3): 481-9, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16727916

RESUMO

Regulation of follicular growth and ovulation as well as steroid production by the ovary depends principally on gonadotropins. However nonsteroid systemic hormones and autocrine and paracrine factors contribute to the regulation of ovarian function. The objectives of the present work were 1) to asses the presence of growth hormone (GH) and prolactin (PRL) in fluid drawn from normal bovine ovarian follicles, cysts or cystic corpora lutea; 2) to relate the stage of luteinization of the cyst with the GH and PRL concentrations in fluids; and 3) to asses the feasibility of providing a defined nonsteroid hormone marker to distinguish between normal and pathological ovarian structures. Cysts were classified according to histological and morphological appearance as follicular or luteal. Concentrations of GH, PRL, estrogens (E2), progesterone (P4) and testosterone (T) were measured in follicular and cystic fluids. On the basis of the E2 to P4 ratio, ovarian formation classes were further divided into two subclasses (E2 dominant and P4 dominant). The results provide evidence of 1) the presence of immunoreactive GH and PRL in all the follicular and cystic fluids assayed, 2) an increasing concentration of GH correlated to the stage of luteinization of the cyst and a direct correlation between GH and P4 concentrations, 3) a significant variability of intraovarian fluid PRL concentration not related to the histological class of the cyst nor to the concentrations of steroid hormones examined, and 4) the possibility of distinguishing 6 different ovarian formation classes by merely measuring GH, P4, E2 and T concentrations in fluids. These data contribute to a better understanding of the endocrine milieu of bovine ovarian cystic degeneration.

19.
Theriogenology ; 49(7): 1377-87, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-10732074

RESUMO

Prolactin and GH have been detected within the ovary, and it has become increasingly evident that they have a role as intrafollicular regulatory factors. The aim of the present work was to gain an insight into the elements influencing intraovarian GH and PRL in bovine species and to see whether cystic degeneration was accompanied by abnormal bovine GH (bGH) and PRL (bPRL) plasma patterns. We followed the relationships between plasma and ovarian fluid bGH and bPRL concentrations over an entire year in Friesian cows whose ovaries showed distinct types of structures. To assess the presence of bGH and bPRL within ovarian cells, we assayed selected ovarian structures by immunohistochemistry. The results demonstrated that: 1) plasma and ovarian fluid hormonal concentrations were independent, and their ratio was independent of the ovarian structure classes, subclasses and period of the year; 2) in the majority of the cows the concentration of bGH in ovarian fluid was no more than 80% of the level in plasma, whereas in about half the animals bPRL concentrations were higher in the ovary than in peripheral plasma; 3) mean bPRL concentrations in ovarian fluids were significantly higher in summer than in winter; 4) immunoreactive bGH and bPRL were present within granulosa and luteal cells. Thus, it is suggested that in the cow bGH and bPRL levels in the ovary might be regulated in some way independently of the pituitary.


Assuntos
Bovinos/fisiologia , Hormônio do Crescimento/metabolismo , Cistos Ovarianos/veterinária , Folículo Ovariano/metabolismo , Prolactina/metabolismo , Animais , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/patologia , Estradiol/análise , Feminino , Hormônio do Crescimento/análise , Hormônio do Crescimento/sangue , Técnicas Imunoenzimáticas/veterinária , Imuno-Histoquímica , Cistos Ovarianos/química , Cistos Ovarianos/metabolismo , Cistos Ovarianos/patologia , Folículo Ovariano/química , Folículo Ovariano/citologia , Progesterona/análise , Prolactina/análise , Prolactina/sangue , Estações do Ano , Estatísticas não Paramétricas
20.
J AOAC Int ; 84(5): 1600-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11601482

RESUMO

Isoelectric focusing in polyacrylamide gel was used to establish an identification archive of fish species belonging to the orders Pleuronectiformes, or flat fish, and Gadiformes, or gadoid fish. The 2 orders include species of different commercial value and interest that are frequently requested in European fish markets, but are susceptible to substitution either because they are morphologically similar or because they arrive on the markets already filleted or sliced. The sarcoplasmic protein profiles are species-specific and reproducible. The use of densitometry and image analysis coupled with a simple computer program overcomes the subjective evaluation of the patterns, making it possible to identify species correctly.


Assuntos
Peixes/metabolismo , Linguados/metabolismo , Carne/análise , Animais , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Focalização Isoelétrica , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa