Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Spinal Cord ; 55(1): 39-46, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27349605

RESUMO

STUDY DESIGN: This is a prospective observational study. OBJECTIVES: The objective of this study was to determine time-dependent changes in diurnal blood pressure (BP) and urine production in acute spinal cord injury (SCI). SETTING: This study was conducted in a specialist, state-based spinal cord service in Victoria, Australia. METHODS: Consenting patients admitted consecutively with acute SCI were compared with patients confined to bed rest while awaiting surgery and with mobilising able-bodied controls. Participants underwent ambulatory BP monitoring (ABPM), measurement of diurnal urine production and rated orthostatic symptoms over 1 year. Participants with night:day systolic BP (SBP) <90% were classified as dippers, 90-100% as non-dippers and >100% as reverse dippers. RESULTS: Participants comprised tetraplegics (n=47, 40.0±17.3 years), paraplegics (n=35, 34.4±13.9 years), immobilised (n=18, 30.9±11.3 years) and mobilising (n=44, 33.1±13.5 years) controls. At baseline, 24-h BP was significantly lower in tetraplegics (111.8±1.9/62.1±1.1 mm Hg) but not in paraplegics (116.7± 1.4/66.0±1.1 mm Hg), compared with controls (117.1 ±1.3/69.1±1.1 mm Hg), adjusting for gender. This difference was not observed at 1 year. The average night:day SBP in mobilising controls was 86.1±0.7%, differing from paraplegics (94.0±1.5%, P<0.001) and tetraplegics (101.5±1.5%, P<0.001). Urine production in tetraplegics and paraplegics did not fall at night compared with the day. Abnormal diurnal BP and orthostatic symptoms in tetraplegics persisted throughout the study. Nocturnal hypertension was observed in 27% (n=9) of tetraplegics, of whom only 2 had day hypertension. All mobilising controls with nocturnal hypertension (n=6, 14%) had day hypertension. CONCLUSION: People with SCI have a high prevalence of isolated nocturnal hypertension, reverse dipping, orthostatic intolerance and nocturnal polyuria. Cardiovascular risk management and assessment of orthostatic symptoms should include ABPM.


Assuntos
Pressão Sanguínea/fisiologia , Ritmo Circadiano/fisiologia , Traumatismos da Medula Espinal/sangue , Traumatismos da Medula Espinal/urina , Doença Aguda , Adolescente , Adulto , Idoso , Monitorização Ambulatorial da Pressão Arterial , Feminino , Humanos , Hipertensão/sangue , Hipertensão/epidemiologia , Hipertensão/etiologia , Hipertensão/urina , Masculino , Pessoa de Meia-Idade , Paralisia/sangue , Paralisia/epidemiologia , Paralisia/etiologia , Paralisia/urina , Fotoperíodo , Poliúria/sangue , Poliúria/epidemiologia , Poliúria/etiologia , Poliúria/urina , Prevalência , Caracteres Sexuais , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/epidemiologia , Coleta de Urina , Adulto Jovem
2.
Spinal Cord ; 53(2): 103-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25448190

RESUMO

STUDY DESIGN: Single centre, single ascending dose study. OBJECTIVES: To compare the pharmacokinetics and assess the safety of capromorelin, a compound that has potential to treat constipation following spinal cord injury (SCI), in groups of able-bodied and SCI volunteers. SETTING: Local population from Victoria, Australia. METHODS: Following initial screening and baseline blood collections, participants received ascending oral doses (20, 50 and then 100 mg at least 1-week apart) of capromorelin after pre-dose blood collection, followed by blood collections over the following 12 h for pharmacokinetic analysis and 1-week and 4-week follow-up blood collections for safety evaluations. Blood pressure and heart rate were monitored. RESULTS: No serious adverse events were recorded following any dose in either the able-bodied group or the SCI group. There were no abnormal blood pressure or heart rate changes. Minor adverse events resolved quickly without the need for treatment. Pharmacokinetic behaviour was broadly similar between groups, with both exhibiting dose-dependent increases in Cmax and AUC0-∞. The SCI participants showed greater variance in pharmacokinetic parameters and had a slightly delayed Tmax and half-life. CONCLUSION: Capromorelin at the doses tested was safe and well tolerated in both SCI and able-bodied participants and also showed similar pharmacokinetics with dose-dependent increases in concentration and drug exposure.


Assuntos
Fármacos do Sistema Nervoso Autônomo/farmacocinética , Piperidinas/farmacocinética , Pirazóis/farmacocinética , Traumatismos da Medula Espinal/sangue , Traumatismos da Medula Espinal/tratamento farmacológico , Administração Oral , Adulto , Área Sob a Curva , Fármacos do Sistema Nervoso Autônomo/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Seguimentos , Grelina/agonistas , Meia-Vida , Humanos , Masculino , Piperidinas/efeitos adversos , Pirazóis/efeitos adversos , Vitória
3.
Clin Infect Dis ; 58(4): e101-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24170195

RESUMO

BACKGROUND: Multidrug-resistant gram-negative bacterial (MDR-GNB) infections of the prostate are an increasing problem worldwide, particularly complicating transrectal ultrasound (TRUS)-guided prostate biopsy. Fluoroquinolone-based regimens, once the mainstay of many protocols, are increasingly ineffective. Fosfomycin has reasonable in vitro and urinary activity (minimum inhibitory concentration breakpoint ≤64 µg/mL) against MDR-GNB, but its prostatic penetration has been uncertain, so it has not been widely recommended for the prophylaxis or treatment of MDR-GNB prostatitis. METHODS: In a prospective study of healthy men undergoing a transurethral resection of the prostate for benign prostatic hyperplasia, we assessed serum, urine, and prostatic tissue (transition zone [TZ] and peripheral zone [PZ]) fosfomycin concentrations using liquid chromatography-tandem mass spectrometry, following a single 3-g oral fosfomycin dose within 17 hours of surgery. RESULTS: Among the 26 participants, mean plasma and urinary fosfomycin levels were 11.4 ± 7.6 µg/mL and 571 ± 418 µg/mL, 565 ± 149 minutes and 581 ± 150 minutes postdose, respectively. Mean overall prostate fosfomycin levels were 6.5 ± 4.9 µg/g (range, 0.7-22.1 µg/g), with therapeutic concentrations detectable up to 17 hours following the dose. The mean prostate to plasma ratio was 0.67 ± 0.57. Mean concentrations within the TZ vs PZ prostate regions varied significantly (TZ, 8.3 ± 6.6 vs PZ, 4.4 ± 4.1 µg/g; P = .001). Only 1 patient had a mean prostatic fosfomycin concentration of <1 µg/g, whereas the majority (70%) had concentrations ≥4 µg/g. CONCLUSIONS: Fosfomycin appears to achieve reasonable intraprostatic concentrations in uninflamed prostate following a single 3-g oral dose, such that it may be a potential option for prophylaxis pre-TRUS prostate biopsy and possibly for the treatment of MDR-GNB prostatitis. Formal clinical studies are now required.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Fosfomicina/administração & dosagem , Fosfomicina/farmacocinética , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Próstata/química , Prostatite/tratamento farmacológico , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Soro/química , Espectrometria de Massas em Tandem , Urina/química
4.
Mol Cell Biol ; 13(3): 1554-64, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8441397

RESUMO

The overexpression of major histocompatibility complex (MHC) class I molecules in endocrine epithelial cells is an early feature of autoimmune thyroid disease and insulin-dependent diabetes mellitus, which may reflect a cellular response, e.g., to viruses or toxins. Evidence from a transgenic model in pancreatic beta cells suggests that MHC class I overexpression could play an independent role in endocrine cell destruction. We demonstrate in this study that the transgenic overexpression of an allogeneic MHC class I protein (H-2Kb) linked to the rat thyroglobulin promoter, in H-2Kk mice homozygous for the transgene, leads to thyrocyte atrophy, hypothyroidism, growth retardation, and death. Thyrocyte atrophy occurred in the absence of lymphocytic infiltration. Tolerance to allogeneic class I was revealed by the reduced ability of primed lymphocytes from transgenic mice to lyse H-2Kb target cells in vitro. This nonimmune form of thyrocyte destruction and hypothyroidism recapitulates the beta-cell destruction and diabetes that results from transgenic overexpression of MHC class I molecules in pancreatic beta cells. Thus, we conclude that overexpression of MHC class I molecules may be a general mechanism that directly impairs endocrine epithelial cell viability.


Assuntos
Genes MHC Classe I/genética , Antígenos H-2/genética , Isoantígenos/genética , Glândula Tireoide/patologia , Animais , Atrofia , Doenças Autoimunes/etiologia , Cruzamentos Genéticos , Citotoxicidade Imunológica , DNA Recombinante/genética , Imunofluorescência , Antígenos H-2/biossíntese , Antígenos H-2/isolamento & purificação , Heterozigoto , Homozigoto , Isoantígenos/biossíntese , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos/imunologia , Regiões Promotoras Genéticas/genética , Ratos/genética , Proteínas Recombinantes/biossíntese , Linfócitos T Citotóxicos , Tireoglobulina/genética , Glândula Tireoide/ultraestrutura
5.
Circ Res ; 89(1): 92-8, 2001 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-11440983

RESUMO

Protease-activated receptor (PAR)1 and PAR2 are expressed on vascular endothelial cells and mediate endothelium-dependent relaxation in several species, and PAR4 agonists cause similar responses in rat aortas. To date, only PAR1 has been reported to mediate relaxation of human arteries despite endothelial cell expression of both PAR1 and PAR2 in these tissues. Because inflammatory stimuli increase PAR2 expression in human endothelial cells in culture, the present study investigated the effect of similar stimuli on PARs in human isolated coronary arteries (HCAs). In HCA ring segments suspended for isometric tension measurements, the selective PAR1-activating peptide, TFLLR (0.01 to 10 micromol/L), caused endothelium-dependent relaxation of precontracted preparations. Little or no change in vascular tension was elicited by either the PAR2- or PAR4-activating peptides, SLIGKV and GYPGQV, respectively (up to 100 micromol/L). Exposure of HCAs to interleukin (IL)-1alpha (1 ng/mL, 12 hours) or tumor necrosis factor-alpha (3 nmol/L, 12 hours) did not affect PAR1 expression but increased PAR2 and PAR4 mRNA levels by approximately 5- and 4-fold, respectively, as determined by quantitative polymerase chain reaction. Similar IL-1alpha treatment did not affect TFLLR-induced relaxations but revealed significant endothelium-dependent relaxations to SLIGKV (100 micromol/L, 61.4+/-6.7%) and GYPGQV (100 micromol/L, 34.8+/-6.4%). These studies are the first to demonstrate functional PAR2 and PAR4 in human arteries in situ. The selective upregulation of PAR2 and PAR4 expression and the increased vascular response in HCAs after exposure to inflammatory stimuli suggest a role for these endothelial receptors during inflammation.


Assuntos
Vasos Coronários/fisiologia , Endotélio Vascular/fisiologia , Mediadores da Inflamação/farmacologia , Receptores de Trombina/biossíntese , Proteínas de Saccharomyces cerevisiae , Vasodilatação , Adulto , Vasos Coronários/metabolismo , Técnicas de Cultura , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Feminino , Humanos , Imuno-Histoquímica , Interleucina-1/farmacologia , Contração Isométrica , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/farmacologia , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , Receptor PAR-2 , Receptores de Trombina/agonistas , Receptores de Trombina/genética , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Fatores de Transcrição/imunologia , Fator de Necrose Tumoral alfa/farmacologia , Regulação para Cima , Vasodilatação/efeitos dos fármacos
6.
Eur J Ophthalmol ; 15(3): 315-23, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15944998

RESUMO

PURPOSE: Graves' ophthalmopathy (GO) is a controversial disease, with disagreement within the medical community regarding its pathogenesis, diagnosis, and treatment. METHODS: We reviewed recent literature on clinical and pathological aspects of GO from both the endocrinologist's and ophthalmologist's perspective. RESULTS: Investigations into the pathogenesis of GO have included possible antigenic targets, orbital cell types, and development of animal models. Diagnosis has been improved recently with new tools and grading systems, but can be complicated by conditions that may simulate one or more of the findings of GO. The new findings of clinical studies also compel practitioners to reassess commonly used GO treatments such as orbital irradiation. CONCLUSIONS: Improved understanding of the pathogenic mechanisms of GO should hopefully lead to new diagnostic and therapeutic approaches to this problematic condition.


Assuntos
Doença de Graves , Animais , Modelos Animais de Doenças , Doença de Graves/diagnóstico , Doença de Graves/patologia , Doença de Graves/terapia , Humanos
7.
Diabetes Care ; 10(5): 573-8, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3315514

RESUMO

This study, in 3 phases, compared the long-term acceptability and efficacy of insulin administered by nasal spray with an intensified subcutaneous regimen in nine type I (insulin-dependent) diabetic subjects on baseline therapy with ultralente insulin. In phase 1, patients were begun and stabilized on a regimen of ultralente daily and Actrapid insulin three times daily. Phase 2 consisted of 4 mo of this intensified subcutaneous regimen. In phase 3, intranasal administration of insulin, with 1% (wt/vol) sodium glycocholate, replaced Actrapid insulin for 4 mo. Glycemic control was compared in each of the three phases. It was possible to maintain the dose of ultralente insulin relatively constant in only six of the nine subjects during the intranasal phase of the study. The six subjects showed a significant rise in glycosylated hemoglobin during the intranasal phase (10.4 +/- 0.6% intranasal vs. 9.1 +/- 0.3% subcutaneous, P less than .05) but not in plasma or urinary glucose levels. There was no significant change in the incidence of hypoglycemic episodes during intranasal insulin therapy in this group. The other three subjects were considered treatment failures. Six of the nine original subjects expressed a preference for intranasal insulin, and one subject complained of mild nasal irritation insufficient to cease treatment. The intranasal route of administration of insulin has the potential to replace short-acting insulin as an adjunct to longer-acting insulin in some insulin-treated diabetic patients.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Insulina/uso terapêutico , Administração Intranasal , Adolescente , Adulto , Aerossóis , Feminino , Humanos , Injeções Subcutâneas , Insulina/administração & dosagem , Insulina Isófana/administração & dosagem , Insulina Isófana/uso terapêutico , Insulina de Ação Prolongada/administração & dosagem , Insulina de Ação Prolongada/uso terapêutico , Insulina Regular de Porco , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
8.
Endocrinology ; 124(5): 2289-96, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2707157

RESUMO

We have studied the binding of recombinant human insulin-like growth factor I (hIGF-I), and hIGF-II, and rat IGF-II [rIGF-II (multiplication-stimulating activity)] to the human amniotic fluid IGF-binding protein placental protein-12 (PP12). PP12 displayed a 5- to 10-fold higher affinity for IGF-I compared to hIGF-II or rIGF-II. These differences in binding affinity were confirmed by both saturation binding analysis and competitive binding analysis using 125I-labeled IGF-I, hIGF-II, and rIGF-II and each of the unlabeled ligands. PP12 produced dose-dependent inhibition of IGF-I-stimulated [3H]thymidine incorporation in the rat thyroid follicular cell line FRTL5. Inhibition of IGF-I-stimulated thymidine incorporation paralleled the ability of PP12 to inhibit IGF-I binding to the surface of FRTL5. At a high concentration, PP12 also inhibited TSH-stimulated DNA synthesis but did not inhibit the binding of 125I-labeled TSH to FRTL5. Insulin did not inhibit the binding of 125I-labeled IGFs to PP12, and PP12 did not inhibit the ability of insulin to stimulate DNA synthesis. These data suggest that the ability of PP12 to inhibit TSH-stimulated DNA synthesis is through the inactivation of IGF produced endogenously by FRTL5. Low concentrations of PP12 produced a statistically significant enhancement of TSH-stimulated DNA synthesis; the mechanism by which this occurs remains unclear.


Assuntos
Líquido Amniótico/análise , Proteínas de Transporte/metabolismo , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina , Fator de Crescimento Insulin-Like I/metabolismo , Proteínas da Gravidez/metabolismo , Somatomedinas/metabolismo , Glândula Tireoide/metabolismo , Animais , Ligação Competitiva , Linhagem Celular , Feminino , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina , Fator de Crescimento Insulin-Like I/isolamento & purificação , Fator de Crescimento Insulin-Like I/farmacologia , Proteínas da Gravidez/farmacologia , Ratos , Somatomedinas/farmacologia , Timidina/metabolismo , Glândula Tireoide/citologia , Glândula Tireoide/efeitos dos fármacos , Tireotropina/metabolismo , Tireotropina/farmacologia
9.
Endocrinology ; 125(5): 2758-65, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2477235

RESUMO

Adenosine inhibits TSH-stimulated [3H]thymidine incorporation into DNA in FRTL5 thyroid follicular cells by both inhibiting cAMP generation and acting at a locus beyond adenylate cyclase. On the other hand, adenosine markedly potentiates DNA synthesis in FRTL5 stimulated by insulin-like growth factor-I (IGF-I). The mechanisms of this latter effect are unknown, but require the coincubation of adenosine and IGF-I and not mediated by an increase in intracellular cAMP concentration. Adenosine increases the maximal response of FRTL5 to [3H]thymidine incorporation stimulated by IGF-I and increases the sensitivity of FRTL5 to IGF-I. These effects of adenosine are reflected by an increase in nuclear labeling as well as by an increase in [3H]thymidine incorporation into DNA. Adenosine also plays a role as an autocrine growth factor in FRTL5, since adenosine deaminase increases the response of these cells to TSH. The effects of adenosine on both TSH- and IGF-I-stimulated DNA synthesis are shared by guanosine and inosine, although with different potencies for the various guanine nucleosides. Inosine potentiates IGF-I-stimulated DNA synthesis, but inhibits TSH-stimulated DNA synthesis only weakly. Adenosine interacts with multiple receptors and with multiple postreceptor pathways in FRTL5 to produce divergent effects on the control of cell replication by two growth factors (TSH and IGF-I) that act through different postreceptor pathways.


Assuntos
Adenosina/farmacologia , Replicação do DNA/efeitos dos fármacos , DNA/biossíntese , Fator de Crescimento Insulin-Like I/farmacologia , Somatomedinas/farmacologia , Glândula Tireoide/metabolismo , Tireotropina/farmacologia , 1-Metil-3-Isobutilxantina/farmacologia , Adenosina Desaminase/farmacologia , Animais , Bucladesina/farmacologia , Linhagem Celular , Toxina da Cólera/farmacologia , Colforsina/farmacologia , DNA/efeitos dos fármacos , Sinergismo Farmacológico , Cinética , Timidina/metabolismo , Glândula Tireoide/efeitos dos fármacos , Tireotropina/antagonistas & inibidores
10.
Endocrinology ; 142(3): 1349-56, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11181554

RESUMO

The tissue distribution, cellular localization, and level of expression of angiotensin II (Ang II) receptors were examined in the normal human prostate and benign prostatic hyperplasia (BPH) by in vitro autoradiography, immunohistochemistry, and radioligand binding studies. In the normal human prostate, Ang II receptors were of the AT(1) subtype and localized predominantly to periurethral stromal smooth muscle. The AT(1) receptor antagonist losartan totally displaced specific [(125)I]-[Sar(1),Ile(8)]Ang II binding, in a concentration-dependent manner, whereas the AT(2) receptor antagonist PD123319 was without effect. There was no significant difference in receptor affinity, but AT(1) receptor density was markedly reduced in BPH compared with that in normal prostate. In rat prostate, Ang II (0.01-1 microM) produced a concentration-dependent increase in [(3)H]-noradrenaline release from sympathetic nerves. The findings of the present study suggest that angiotensin AT(1) receptors predominate in the human prostate. The high concentration of AT(1) receptors in the periurethral region suggests a role for Ang II in modulating cell growth, smooth muscle tone, and possibly micturition. Furthermore, down-regulation of AT(1) receptors in BPH may be due to receptor hyperstimulation by increased local levels of Ang II in BPH. Finally, Ang II may play a functional role in modulating sympathetic transmission in the prostate. These data support the novel concept that activation of the renin-angiotensin system may be involved in the pathophysiology of BPH.


Assuntos
Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Receptores de Angiotensina/metabolismo , Autorradiografia , Ligação Competitiva , Humanos , Imuno-Histoquímica , Masculino , Membranas/metabolismo , Pessoa de Meia-Idade , Norepinefrina/metabolismo , Valores de Referência , Distribuição Tecidual
11.
J Clin Endocrinol Metab ; 86(5): 2315-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11344244

RESUMO

The existence of an autoantigen common to Graves' disease and its associated extrathyroidal manifestations has been proposed. As the TSH receptor (TSHR) is the primary target for autoimmunity against the thyroid in Graves' disease, much effort has gone into investigating the role of TSHR messenger ribonucleic acid (mRNA) transcripts in extrathyroidal tissue, particularly in the orbit. A high stringency RT-PCR technique had previously been employed by our laboratory to demonstrate the presence of full-length and splice variant TSHR mRNA in extraocular muscle (EOM). This technique demonstrated selective amplification of TSHR mRNA transcripts in thyroid and EOM, but not in abdominal muscle, kidney, or brain tissue. We used this technique in the present study to investigate the reported presence of TSHR mRNA transcripts in cardiac tissue. After removal of all visible fat from muscle tissues, high stringency RT-PCR was performed, and we found no TSHR transcripts in the muscle of any chamber of the normal human heart. In addition, in situ hybridization on fresh-frozen and paraffin-embedded sections confirmed the presence of TSHR transcripts in thyroid and EOM, but not in abdominal or cardiac muscle. These findings support the hypothesis that the TSHR is a shared antigen in the thyroid and EOM, but not in cardiac muscle.


Assuntos
Doença de Graves/metabolismo , Músculos/metabolismo , Miocárdio/metabolismo , RNA Mensageiro/análise , Receptores da Tireotropina/genética , Idoso , Autorradiografia , Southern Blotting , Doença de Graves/complicações , Humanos , Hibridização In Situ , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Neurology ; 55(3): 435-7, 2000 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-10932283

RESUMO

The authors analyzed the association between APOE epsilon4 genotype and clinical and MRI findings in 43 refractory temporal lobe epilepsy patients. The distribution of the alleles were normal. Ten patients (23%) had an APOE epsilon 4 allele and had an earlier onset of habitual seizures (with epsilon4 5 +/- 5 years; without epsilon4 15 +/- 10 years). Quantitative MRI findings were not influenced by the APOE epsilon4 genotype. APOE epsilon4 may shorten the latency between an initial injury and seizure onset.


Assuntos
Apolipoproteínas E/genética , Epilepsia do Lobo Temporal/genética , Adulto , Idade de Início , Alelos , Apolipoproteína E4 , Atrofia , Doença Crônica , Epilepsia do Lobo Temporal/patologia , Feminino , Genótipo , Hipocampo/patologia , Humanos , Masculino , Pessoa de Meia-Idade
13.
Endocrinol Metab Clin North Am ; 19(3): 479-93, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2175702

RESUMO

Normal and neoplastic thyroid tissues express a variety of oncogenes, growth factors, and growth factor receptors. The increased expression of a mutated form or forms of c-myc and c-ras appears to be associated with some epithelial and medullary thyroid carcinomas. In some cases the presence of these oncogenes correlates with less favorable histologic appearance. The possibility of cooperation between oncogene products (myc and ras) in neoplastic development is raised by studies on transformed thyroid cells in culture. Moreover, a tissue-specific oncogene associated with papillary carcinoma recently has been described. The role of excessive growth factor or growth factor receptor expression in thyroid carcinoma also has been discussed and may, as with other tumor types, be linked to specific oncogene products (e.g., c-erb-B encoding for the EGF receptor). However, the regulation of oncogenes in various stages of differentiation of thyroid tissues is not well understood. In addition to describing these associations with thyroid carcinoma and putative unchecked growth factor action in the development of neoplasia, more direct demonstrations of a causal relationship are necessary. Thus, one needs to overexpress oncogenes/growth factors in normal cell lines (as has been described in this review) and observe whether cellular transformation or dedifferentiation or both occur. The ability to specifically block oncogene or growth factor expression in neoplastic cell lines at the RNA or protein level (with antisense oligonucleotides or monoclonal antibodies, respectively) should provide important information about the pathogenetic importance of these factors. It may be anticipated that reversing the overexpression of certain oncogenes can lead to normal cellular proliferation, morphology, and differentiation. The knowledge obtained from investigating the associations of oncogenes and growth factors with thyroid cancer should provide insight into the mechanisms involved in cell growth and differentiation and in the biochemical steps involved in neoplastic transformation. New insights into these processes may lead to specific therapeutic measures designed to block aberrant expression of the cellular products involved in neoplasia. A more complete understanding of the role of oncogenes in thyroid cancer also may lead to the development of specific tumor markers that may be useful in the early diagnosis of thyroid cancer and the follow-up of therapeutic maneuvers. If specific markers can be identified, analysis of fine-needle aspiration specimens of the thyroid or imaging techniques (using for example, oncogene-specific monoclonal antibodies) could be added to the diagnostic armamentarium for thyroid disease.


Assuntos
Substâncias de Crescimento/fisiologia , Oncogenes/fisiologia , Neoplasias da Glândula Tireoide/etiologia , Adenocarcinoma/genética , Carcinoma/genética , Carcinoma Papilar/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Receptores de Superfície Celular/fisiologia , Neoplasias da Glândula Tireoide/genética
14.
J Endocrinol ; 171(1): 97-108, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11572794

RESUMO

The renin-angiotensin system (RAS) is present in the human prostate and may be activated in benign prostatic hyperplasia (BPH), possibly contributing to the pathophysiology of this disorder by enhancing local sympathetic tone and cell growth. The functional role of the RAS in the prostate, however, is unknown. The present study was undertaken to determine whether angiotensin (Ang) II enhances sympathetic transmission in the prostate. The neuronal stores of the rat prostate were labelled with [(3)H]noradrenaline (NA). Ang II and Ang I enhanced [(3)H]NA release in a concentration-dependent manner. The Ang II receptor subtype 1 (AT(1) receptor) antagonist losartan and the AT(2) receptor antagonist PD123319 inhibited this facilitatory effect of Ang II and Ang I, whereas the other AT(2) receptor antagonist, CGP42112, was without effect. Bradykinin also increased [(3)H]NA release, which was inhibited by the B(2) receptor antagonist Hoe140. The angiotensin-converting enzyme inhibitor captopril inhibited the effect of Ang I, but potentiated that of bradykinin. Interestingly, captopril alone produced an increase in [(3)H]NA release which was inhibited by Hoe140. Losartan, but not PD123319 or CGP42112, inhibited [(125)I]-Ang II binding in Chinese hamster ovary cells transfected with the AT(1a) or AT(1b) receptor. In contrast, in cells expressing the AT(2) receptor, PD123319 and CGP42112, but not losartan, inhibited [(125)I]-Ang II binding. In conclusion, Ang II enhances the release of NA from sympathetic nerves of the rat prostate via a novel functional receptor distinct from the cloned AT(1a), AT(1b) or AT(2). These data provide direct evidence in support of a functional role for the local RAS in modulating sympathetic transmission in the prostate, which may have important implications for the pathophysiology of BPH.


Assuntos
Angiotensina II/farmacologia , Bradicinina/análogos & derivados , Norepinefrina/metabolismo , Próstata/inervação , Hiperplasia Prostática/fisiopatologia , Receptores de Angiotensina/metabolismo , Sistema Nervoso Simpático/metabolismo , Análise de Variância , Angiotensina I/farmacologia , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Bradicinina/farmacologia , Células CHO/efeitos dos fármacos , Captopril/farmacologia , Cricetinae , Relação Dose-Resposta a Droga , Imidazóis/farmacologia , Losartan/farmacologia , Masculino , Oligopeptídeos/farmacologia , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Sistema Nervoso Simpático/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos
15.
Mol Cell Endocrinol ; 184(1-2): 187-92, 2001 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-11694354

RESUMO

The cellular localisation and expression of angiotensin AT(4) receptors was examined in the normal human prostate and benign prostatic hyperplasia (BPH) by quantitative in vitro autoradiography using [(125)I]-Ang IV. In the normal human prostate, AT(4) receptors were localised to the glandular epithelium. Interestingly, specific AT(4) receptor binding was significantly reduced in BPH compared to the normal prostate, as quantitated macroscopically (normal: 5038+/-476 dpm/mm(2), n=6 vs BPH: 2701+/-176 dpm/mm(2), n=6, P<0.001) and microscopically (normal: 7.28+/-0.36 grains/mm(2), n=6 vs BPH: 2.50+/-0.47 grains/mm(2), n=6, P<0.001). The findings of the present study demonstrate the presence of AT(4) receptors in the human prostate, being localised to the glandular epithelium, which suggest that the Ang IV/AT(4) system may play a role in the regulation of ionic transport and glandular secretion in the human prostate. The observation that AT(4) receptors appear reduced in BPH suggests that the AT(4) receptor may undergo agonist-induced receptor internalisation, possibly due to increased local tissue levels of Ang IV in BPH.


Assuntos
Próstata/química , Hiperplasia Prostática/metabolismo , Receptores de Angiotensina/metabolismo , Autorradiografia , Células Epiteliais/química , Humanos , Radioisótopos do Iodo , Masculino , Próstata/citologia , Hiperplasia Prostática/patologia , Ligação Proteica , Receptores de Angiotensina/análise , Distribuição Tecidual
16.
Diabetes Res Clin Pract ; 3(4): 197-202, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3304906

RESUMO

The comparative effects of intranasal and subcutaneous insulin on blood glucose and insulin levels are described in non-obese type II diabetics, in the fasting state and following a standard meal. In the fasting studies, intranasal insulin (30 units) produced a single early insulin peak. Elevated insulin levels and their hypoglycaemic effect persisted for less than 2 h whereas with subcutaneous insulin (8 units) elevated insulin levels and evidence of hypoglycaemic action were still present at 4 h. By contrast, in the meal studies both forms of insulin had similar effects on serum insulin levels and blood glucose. Moreover elevated insulin levels and evidence of reduction in post-prandial hyperglycaemia were now present at 4 h with both intranasal and subcutaneous insulin administration. Intranasal insulin in combination with a test meal now produced a biphasic insulin profile more closely resembling the normal insulin response to a meal, and reflecting the combined effects of endogenous and exogenous insulin.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Insulina/administração & dosagem , Administração Intranasal , Idoso , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Ingestão de Alimentos , Jejum , Feminino , Humanos , Injeções Subcutâneas , Insulina/sangue , Masculino , Pessoa de Meia-Idade
17.
Br J Pharmacol ; 171(24): 5459-61, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25442220

RESUMO

UNLABELLED: Cell movement is a fundamental process of normal cellular physiology and pathophysiology. Abnormal regulation of cell migration is a common denominator of many medical disorders, including cancer metastasis, autoimmune disease and inflammation. Increased interest in the targeting of cell migration and invasion, which has potential for therapeutic intervention in many diseases are behind this special themed issue. Thus, the focus of this issue is centred on the control of cellular cytoskeletal dynamics and cellular or tissue microenvironment sensors. Novel therapeutic opportunities targeting regulation of cell migration are discussed including the emerging roles of tetraspanins, phosphoinositides, transient receptor potential cation channels, stromal interaction molecules and calcium release-activated calcium modulators. Better understanding of these regulatory factors will hopefully bring greater attention to strategically targeting aberrant cell migration, which has many therapeutic implications for common human diseases. LINKED ARTICLES: This article is part of a themed section on Cytoskeleton, Extracellular Matrix, Cell Migration, Wound Healing and Related Topics. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-24


Assuntos
Doenças Autoimunes/fisiopatologia , Movimento Celular/fisiologia , Citoesqueleto/fisiologia , Inflamação/fisiopatologia , Metástase Neoplásica/fisiopatologia , Humanos , Invasividade Neoplásica/fisiopatologia
18.
Br J Pharmacol ; 171(24): 5462-90, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23731188

RESUMO

UNLABELLED: One of the hallmarks of cancer is the ability to activate invasion and metastasis. Cancer morbidity and mortality are largely related to the spread of the primary, localized tumour to adjacent and distant sites. Appropriate management and treatment decisions based on predicting metastatic disease at the time of diagnosis is thus crucial, which supports better understanding of the metastatic process. There are components of metastasis that are common to all primary tumours: dissociation from the primary tumour mass, reorganization/remodelling of extracellular matrix, cell migration, recognition and movement through endothelial cells and the vascular circulation and lodgement and proliferation within ectopic stroma. One of the key and initial events is the increased ability of cancer cells to move, escaping the regulation of normal physiological control. The cellular cytoskeleton plays an important role in cancer cell motility and active cytoskeletal rearrangement can result in metastatic disease. This active change in cytoskeletal dynamics results in manipulation of plasma membrane and cellular balance between cellular adhesion and motility which in turn determines cancer cell movement. Members of the tetraspanin family of proteins play important roles in regulation of cancer cell migration and cancer-endothelial cell interactions, which are critical for cancer invasion and metastasis. Their involvements in active cytoskeletal dynamics, cancer metastasis and potential clinical application will be discussed in this review. In particular, the tetraspanin member, CD151, is highlighted for its major role in cancer invasion and metastasis. LINKED ARTICLES: This article is part of a themed section on Cytoskeleton, Extracellular Matrix, Cell Migration, Wound Healing and Related Topics. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-24.


Assuntos
Membrana Celular/metabolismo , Movimento Celular , Células Endoteliais/metabolismo , Matriz Extracelular/metabolismo , Metástase Neoplásica , Tetraspaninas/metabolismo , Microambiente Tumoral , Adesão Celular , Humanos , Tetraspanina 24/metabolismo
20.
Mol Cell Endocrinol ; 302(2): 219-29, 2009 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-18824067

RESUMO

Prostate cancer is highly prevalent in Western society, and its early stages can be controlled by androgen ablation therapy. However, the cancer eventually regresses to an androgen-independent state for which there is no effective treatment. The renin-angiotensin system (RAS), in particular the octapeptide angiotensin II, is now recognised to have important effects on growth factor signalling and cell growth in addition to its well known actions on blood pressure, fluid homeostasis and electrolyte balance. All components of the RAS have been recently identified in the prostate, consistent with the expression of a local RAS system in this tissue. This review focuses on the role of the RAS in the prostate, and the possibility that this pathway may be a potential therapeutic target for the treatment of prostate cancer and other prostatic diseases.


Assuntos
Neoplasias da Próstata/metabolismo , Sistema Renina-Angiotensina/fisiologia , Humanos , Masculino , Próstata/química , Neoplasias da Próstata/tratamento farmacológico , Receptores de Angiotensina/efeitos dos fármacos , Sistema Renina-Angiotensina/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA