RESUMO
A 28-year-old male musical student has been presented with visible inability of active abduction and extension of the thumbs in both hands beyond the neutral position. The student has not been previously diagnosed and claimed no history of trauma or surgical procedures in the area of hands and no family history of such disabilities. The student remained capable of playing on keyboard instruments on high level due to compensation by hyperextension of the interphalangeal joint of both thumbs and showed no increased frequency of the injuries or playing-related disorders. The ultrasound and magnetic resonance imaging showed complete bilateral agenesis of extensor pollicis brevis muscles and was classified as isolated congenital clasped thumb syndrome. Due to the age of the student and the agenesis of the muscles the conservative treatment was deemed inadequate and due to high functionality of the student as a musician and unforeseeable results it might have on a musician's career, surgical treatment has been disadvised.
Assuntos
Anormalidades Múltiplas , Músculo Esquelético , Masculino , Humanos , Adulto , Músculo Esquelético/diagnóstico por imagem , Polegar/anormalidades , Polegar/lesões , Polegar/cirurgia , Mãos , Imageamento por Ressonância MagnéticaRESUMO
BACKGROUND: The sesamoid bones are small, usually oval bone structures often found in joints and under the tendons. Although their precise function is not fully understood, it is agreed upon that they protect the joints and make movements faster and less energy consuming. Sesamoid bones are found in hands, especially around first, second and fifth metacarpophalangeal joint and the interphalangeal joint of the thumb. MATERIALS AND METHODS: This study compares a group of 32 young musicians to 30 non-musicians of similar age and posture. The hands of the subjects were examined by ultrasound imaging for the presence of sesamoid bones. The results were noted and observed sesamoids were measured. RESULTS: The results seem to prove that although there are no difference in the amount or the location of the sesamoid bones between the musicians and the non-musicians, there is statistically significant tendency for the musicians to have bigger sum of the sesamoid's volume per hand (Fisher's test p-value = 0.034 < 0.05). CONCLUSIONS: There was also observed an unusually shaped "Bactrian" sesamoid bone at the interphalangeal joint of the thumb in 8 cases in the musicians' group and 1 case in the control group. All participants with the aforementioned structure were female.
Assuntos
Ossos Sesamoides , Feminino , Mãos , Humanos , Radiografia , Ossos Sesamoides/diagnóstico por imagem , Tendões , PolegarRESUMO
Antibody responses and antigen recognition were monitored during and after treatment with albendazole (ABZ) in nine patients selected from a trichinellosis outbreak that occurred in north-west Poland in 2007. Seven out of the nine patients yielded positive serum IgG response during treatment. One month after treatment, the IgG response decreased in most patients. Serum levels of ABZ and main metabolites greatly varied among patients without correlation with the IgG response. Two-dimensional electrophoresis and western blot with serum from each patient showed highly immunoreactive spots located between 3- 10 pI and 45-97 kDa in all patients. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF) and MALDI-TOF/time-of-flight mass spectrometry (TOF MS) analysis identified actine, enolase, p49 protein, Caenorhabditis elegans-targeted antigen, and serine protease as the most reactive proteins. A minor spot located at 6 pI and 26 kDa identified as annexin I failed recognition in most patients showing decline in IgG response and clinical improvement after treatment. This protein could constitute a sensitive marker for the effectiveness of ABZ against trichinellosis.
RESUMO
Metabotropic glutamate 1 (mGlu) receptor has been proposed as a target for the treatment of metastatic melanoma. Studies have demonstrated that inhibiting the release of glutamate (the natural ligand of mGlu1 receptors), results in a decrease of melanoma tumor growth in mGlu1 receptor-expressing melanomas. Here we demonstrate that mGlu1 receptors, which have been previously characterized as oncogenes, also behave like dependence receptors by creating a dependence on glutamate for sustained cell viability. In the mGlu1 receptor-expressing melanoma cell lines SK-MEL-2 (SK2) and SK-MEL-5 (SK5), we show that glutamate is both necessary and sufficient to maintain cell viability, regardless of underlying genetic mutations. Addition of glutamate increased DNA synthesis, whereas removal of glutamate not only suppressed DNA synthesis but also promoted cell death in SK2 and SK5 melanoma cells. Using genetic and pharmacological inhibitors, we established that this effect of glutamate is mediated by the activation of mGlu1 receptors. The stimulatory potential of mGlu1 receptors was further confirmed in vivo in a melanoma cell xenograft model. In this model, subcutaneous injection of SK5 cells with short hairpin RNA-targeted downregulation of mGlu1 receptors resulted in a decrease in the rate of tumor growth relative to control. We also demonstrate for the first time that a selective mGlu1 receptor antagonist JNJ16259685 ((3,4-Dihydro-2H-pyrano[2,3-b]quinolin-7-yl)-(cis-4-methoxycyclohexyl)-methanone) slows SK2 and SK5 melanoma tumor growth in vivo. Taken together, these data suggest that pharmacological inhibition of mGlu1 receptors may be a novel approach for the treatment of metastatic melanoma.
Assuntos
Sobrevivência Celular/fisiologia , Ácido Glutâmico/metabolismo , Melanoma/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Melanoma/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Quinolinas/farmacologiaRESUMO
Metabotropic glutamate (mGlu) receptors were discovered in the mid 1980s and originally described as glutamate receptors coupled to polyphosphoinositide hydrolysis. Almost 6500 articles have been published since then, and subtype-selective mGlu receptor ligands are now under clinical development for the treatment of a variety of disorders such as Fragile-X syndrome, schizophrenia, Parkinson's disease and L-DOPA-induced dyskinesias, generalized anxiety disorder, chronic pain, and gastroesophageal reflux disorder. Prof. Erminio Costa was linked to the early times of the mGlu receptor history, when a few research groups challenged the general belief that glutamate could only activate ionotropic receptors and all metabolic responses to glutamate were secondary to calcium entry. This review moves from those nostalgic times to the most recent advances in the physiology and pharmacology of mGlu receptors, and highlights the role of individual mGlu receptor subtypes in the pathophysiology of human disorders. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'.
Assuntos
Receptores de Glutamato Metabotrópico/fisiologia , Pesquisa Translacional Biomédica , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Doença de Parkinson/fisiopatologia , Receptores de Glutamato Metabotrópico/química , Receptores de Glutamato Metabotrópico/efeitos dos fármacos , Esquizofrenia/tratamento farmacológico , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatologia , Transtornos Relacionados ao Uso de Substâncias/tratamento farmacológico , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Transtornos Relacionados ao Uso de Substâncias/fisiopatologiaRESUMO
PURPOSE: To investigate the nature of symptomatic visual disturbance in patients with EFEMP1 retinal dystrophy in the absence of geographic atrophy or choroidal neovascularization. METHODS: Patients presenting to a tertiary referral centre underwent clinical evaluation, fluorescein angiography, colour contrast sensitivity, focal, pattern, and standard electroretinography, electrooculography, scotopic threshold perimetry and dark adaptometry. RESULTS: Clinical features included reduced central vision, difficulty passing from light to dark, and diffuse submacular and peripapillary deposits, which were hyperfluorescent by fluorescein angiography. Colour contrast thresholds were abnormal in all six patients studied and both pattern and focal electroretinograms were abnormal in five of six patients. The scotopic and mixed rod-cone single flash ERG was normal but two patients demonstrated reduced oscillatory potentials and one had borderline delayed 30 Hz responses. Scotopic thresholds were elevated and rod-mediated dark adaptation kinetics were markedly prolonged in all six patients when measured over the central visible confluent deposits. CONCLUSIONS: In patients with EFEMP1 retinal dystrophy with confluent macular deposits, scotopic sensitivity is reduced and dark adaptation kinetics are prolonged over the macular deposits but are normal elsewhere. These results emphasize the localised nature of functional deficits in some patients with EFEMP1 retinal dystrophy and correlate well with the patient's visual symptoms. Symptomatic visual dysfunction may precede the development of clinically evident geographic atrophy or choroidal neovascularization in this disorder.
Assuntos
Adaptação à Escuridão , Proteínas da Matriz Extracelular/genética , Mutação , Drusas Retinianas/fisiopatologia , Defeitos da Visão Cromática/etiologia , Sensibilidades de Contraste , Eletrorretinografia , Feminino , Humanos , Degeneração Macular/complicações , Degeneração Macular/genética , Degeneração Macular/fisiopatologia , Pessoa de Meia-Idade , Drusas Retinianas/complicações , Drusas Retinianas/genética , Transtornos da Visão/etiologiaRESUMO
The effects of irradiation on intestinal epithelial cells were analyzed in vivo and in vitro. The in vivo study was carried out on the rat small intestine and for the in vitro study the intestinal crypt cell-line IEC-6 was used. Rat intestine and IEC-6 cells were irradiated with X-ray doses ranging between 1-16 Gy. Energy-dispersive X-ray microanalysis was used for detection of the elemental changes in the cells. Cell morphology was investigated in the scanning electron microscope, DNA-synthesis by autoradiography of 3H-thymidine incorporating nuclei and proliferation by cell counting. Our results indicate that in vivo, in the crypt cells, the increasing doses of irradiation led to increased sodium and lowered potassium and phosphorus concentrations. Corresponding ion shifts were found in the irradiated IEC-6 cells. Cells continued to proliferate up to the dose of 8 Gy, although the proliferation rate became lower with increasing dose of irradiation. The increasing dose of irradiation significantly reduced DNA-synthesis (16 Gy decreased DNA-synthesis by 50%) which resulted in a complete inhibition of cell proliferation. Analysis of goblet cells also showed characteristic radiation-dependent elemental changes. Scanning electron microscopical investigation of cells in culture revealed that most of the control cells were flat and had rather smooth cell membranes. Irradiation led to the appearance of numerous different membrane manifestations (microvilli of varying length and distribution, and blebs). Frequency of differences in the topology of the cells was related to the dose of irradiation. Our study clearly demonstrates that even low doses of irradiation cause changes in the ionic composition of the cells and inhibit DNA-synthesis and cell proliferation. The effects observed in the crypt cells in vivo were the same as in the intestinal cell line in vitro, which indicates that IEC-6 cells can be used for investigation of side effects of radiation to the abdomen.
Assuntos
Células Epiteliais/efeitos da radiação , Intestino Delgado/citologia , Intestino Delgado/efeitos da radiação , Animais , Divisão Celular/efeitos da radiação , Linhagem Celular , Núcleo Celular/ultraestrutura , Células Cultivadas , Citoplasma/ultraestrutura , DNA/biossíntese , DNA/efeitos da radiação , Microanálise por Sonda Eletrônica , Células Epiteliais/metabolismo , Intestino Delgado/metabolismo , Masculino , Microscopia Eletrônica de Varredura , Ratos , Ratos Sprague-Dawley , Fixação de TecidosRESUMO
A panel of 31 long-term non-small cell lung cancer (NSCLC) cell lines was examined for the expression of protein and/or mRNA transcripts for 11 distinct immune response related molecules or tumor associated antigens (TAA). To assess whether cytokine stimulation might up-regulate expression of the genes of interest, cells were cultured in 500 U/ml of gamma-interferon (gamma-IFN) for 48-72 h prior to analysis. Major histocompatibility complex (MHC) Class I antigens were detected by indirect immunofluorescence and were constitutively expressed on all of the cell lines. The average of the mean fluorescence intensity (MFI) measured 222+/-22. gamma-IFN stimulation produced a significant increase to 482+/-36. For MHC Class II only 7/31 cell lines (23%) exhibited constitutive expression, while gamma-IFN treatment had a dramatic effect and yielded 18/31 (58%) positive cell lines. The co-stimulatory molecules CD80 and CD86 were examined by direct immunofluorescence for cell surface expression and RT-PCR amplification for mRNA. CD80 protein was not detected at all, while an insignificant percentage of cells were positive (mean 2%) for CD86 in all cell lines tested. gamma-IFN had no apparent effect on CD80 or CD86 protein expression. Constitutive CD80 or CD86 mRNA levels were observed in 45 and 61% of the NSCLC lines, respectively. These percentages increased to 77% and 90% with gamma-IFN. Cell surface phenotypic analysis for TAA revealed positive populations in 28/31 cell lines (90%) for Her-2/neu, 18/31 (58%) for CEA and 8/31 (26%) for GD-2, with gamma-IFN having no effect. After gamma-IFN stimulation, RT-PCR amplification for Mage-1, -2, -3 and WT-1 detected mRNA in 33%, 33%, 44% and 70% of the cell lines, respectively. Overall, gamma-IFN stimulation led to the up-regulation of MHC Class I molecules and class II molecules as well as CD80 and CD86 mRNA transcripts. This survey represents the first comprehensive analysis of NSCLC cell lines for a variety of molecules that could play an important role in the generation of an NSCLC anti-tumor CD8+ cytotoxic T lymphocyte (CTL) response.
Assuntos
Antígenos CD/genética , Antígenos de Neoplasias/genética , Antígeno B7-1/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Antígenos de Histocompatibilidade/genética , Interferon gama/farmacologia , Neoplasias Pulmonares/metabolismo , Glicoproteínas de Membrana/genética , Células Tumorais Cultivadas/efeitos dos fármacos , Antígenos CD/metabolismo , Antígenos de Neoplasias/metabolismo , Antígeno B7-1/metabolismo , Antígeno B7-2 , Primers do DNA/química , Citometria de Fluxo , Antígenos de Histocompatibilidade/metabolismo , Humanos , Glicoproteínas de Membrana/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas/metabolismo , Regulação para CimaRESUMO
In the complex process of bone formation at the implant-tissue interface, implant surface roughness is an important factor modulating osteoblastic function. In this study, primary cultures of osteoblast-like cells, derived from human mandibular bone, were used. The aim was to examine the effect of varying surface roughness of titanium implant material on cellular attachment, proliferation and differentiation. A recognized method of increasing surface roughness and enlarging the surface area of titanium implants is by blasting with titanium dioxide particles: the four specimen types in the study comprised surfaces which were machine-turned only, or blasted after turning, with 63-90 microm, 106-180 microm, or 180-300 microm TiO(2) particles, respectively. The specimens were analyzed by scanning electron microscopy and confocal laser scanning. The turned samples had the smoothest surfaces: average height deviation (S(a)) of 0.20 microm. The roughest were those blasted with 180-300 microm particles, S(a) value 1.38 microm. Blasting with intermediate particle sizes yielded S(a) values of 0.72 microm and 1.30 microm, respectively. Cell profile areas were measured using a semiautomatic interactive image analyzer. Figures were expressed as percentage of attachment. DNA synthesis was estimated by measuring the amount of [(3)H]-thymidine incorporation into trichloroacetic acid (TCA) insoluble cell precipitates. The specific activity of alkaline phosphatase was assayed using p-nitrophenylphosphate as a substrate. The ability of the cells to synthesize osteocalcin was investigated in serum-free culture medium using the ELSA-OST-NAT immunoradiometric kit. After 3 h of culture, the percentage of cellular attachment did not differ significantly between specimens blasted with 180-300 micromparticles and the turned specimens. All blasted surfaces showed significantly higher [(3)H]-thymidine incorporation than the turned surfaces (P<0.05), with the highest on the surfaces blasted with 180-300 microm particles. Osteocalcin synthesis by the cells in response to stimulation by 1,25(OH)2D3, was also significantly greater (P<0.05) on the surfaces blasted with TiO(2) particles. However, analysis of alkaline phosphatase activity disclosed no significant differences among the four surface modifications. It is concluded that in this cellular model, the proliferation and differentiation of cells derived from human mandibular bone is enhanced by surface roughness of the titanium implant. However, increasing the size of the blasting particles to 300 microm does not further increase the initial attachment of the cells compared to turned surfaces and those blasted with 63-90 microm particles.
Assuntos
Processo Alveolar/citologia , Materiais Biocompatíveis/química , Implantes Dentários , Mandíbula/citologia , Osteoblastos/fisiologia , Titânio/química , Adolescente , Adulto , Fosfatase Alcalina/análise , Adesão Celular , Contagem de Células , Técnicas de Cultura de Células , Diferenciação Celular , Divisão Celular , DNA/biossíntese , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Microscopia Confocal , Microscopia Eletrônica de Varredura , Osteocalcina/biossíntese , Osteogênese/fisiologia , Tamanho da Partícula , Compostos Radiofarmacêuticos , Estatística como Assunto , Propriedades de Superfície , TrítioRESUMO
The chemical synthesis of a series of N(1)-substituted derivatives of (2R,4R)-4-aminopyrrolidine-2,4-dicarboxylic acid [(2R,4R)-APDC] as constrained analogues of gamma-substituted glutamic acids is described. Appropriate substitution of the N(1)-position results in agonist, partial agonist, or antagonist activity at mGluR2, mGluR3, and/or mGluR6.
Assuntos
Pirrolidinas/farmacologia , Receptores de Glutamato Metabotrópico/agonistas , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Animais , Sítios de Ligação/fisiologia , Células CHO , Linhagem Celular , Cricetinae , Ácido Glutâmico/metabolismo , Concentração Inibidora 50 , Ligantes , Pirrolidinas/síntese química , Receptores de Glutamato/metabolismoAssuntos
Carboxipeptidases/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Fármacos Neuroprotetores/síntese química , Ureia/análogos & derivados , Ureia/síntese química , Animais , Encéfalo/enzimologia , Células Cultivadas , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Agonistas de Aminoácidos Excitatórios , Glutamato Carboxipeptidase II , N-Metilaspartato , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Ratos , Relação Estrutura-Atividade , Ureia/química , Ureia/farmacologiaRESUMO
BACKGROUND: The epithelial cell adhesion molecule CEACAM1 exhibits an interesting dynamic expression during tooth development. It is first expressed in the reduced enamel epithelium, its expression then increases in the orally faced reduced epithelium and the overlying oral epithelium that then fuse to give rise to the junctional epithelium. The expression of CEACAM1 remains at high levels in the junctional epithelium, in contrast to the surrounding oral sulcular epithelium which shows much lower expression levels. We investigated if the high expression levels of CEACAM1 and the loosely organized cells characteristic of the junctional epithelium are genetically programmed or result from bacterial infiltration. METHODS: Oral tissues from germ-free rats and mice and animals with conventional bacterial flora were analyzed by transmission electron microscopy and immunohistochemical staining for CEACAM1. RESULTS: The junctional epithelium of both germ-free and conventional animals was identical with respect to both CEACAM1 expression and morphology. Also the presence of leukocytes was the same in both types of animals. CONCLUSIONS: The results indicate that the characteristic morphology and the high expression levels of CEACAM1 in the junctional epithelium are genetically programmed and not a result of bacterial infiltration. This suggests that CEACAM1 has an important role for the structural integrity of the junctional epithelium. This conclusion was supported by the observation that the junctional epithelium does not express any E-cadherin, which is another abundant epithelial cell adhesion molecule.
Assuntos
Antígenos CD/genética , Antígenos de Diferenciação/genética , Fenômenos Fisiológicos Bacterianos , Moléculas de Adesão Celular/genética , Inserção Epitelial/metabolismo , Epitopos/genética , Animais , Antígenos CD/análise , Antígenos de Diferenciação/análise , Caderinas/análise , Caderinas/genética , Antígeno Carcinoembrionário , Moléculas de Adesão Celular/análise , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Corantes , Esmalte Dentário/citologia , Esmalte Dentário/metabolismo , Modelos Animais de Doenças , Inserção Epitelial/citologia , Inserção Epitelial/microbiologia , Células Epiteliais/metabolismo , Epitopos/análise , Expressão Gênica , Vida Livre de Germes , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Microvilosidades/metabolismo , Microvilosidades/ultraestrutura , Mucosa Bucal/citologia , Mucosa Bucal/metabolismo , Ratos , Ratos EndogâmicosRESUMO
We report an unusual case of endometritis caused by Trichosporon beigelii in an elderly woman who had no clinically obvious immunosuppression nor even clinically obvious skin disease. No evidence of predisposing factors for deep trichosporonosis was identified in this patient, who apparently is of normal immune status.
Assuntos
Endometrite/diagnóstico , Micoses/diagnóstico , Trichosporon/isolamento & purificação , Idoso , Endometrite/microbiologia , Feminino , Humanos , Imunocompetência , Micoses/microbiologiaAssuntos
Carboxipeptidases/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Antagonistas de Aminoácidos Excitatórios/síntese química , Glutaratos/síntese química , Ácidos Fosfínicos/síntese química , Receptores de Glutamato Metabotrópico/agonistas , Animais , Células CHO , Linhagem Celular , Cricetinae , Dipeptídeos/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Antagonistas de Aminoácidos Excitatórios/química , Antagonistas de Aminoácidos Excitatórios/farmacologia , Glutamato Carboxipeptidase II , Glutaratos/química , Glutaratos/farmacologia , Ligantes , Ácidos Fosfínicos/química , Ácidos Fosfínicos/farmacologia , Ratos , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
This study was performed to determine the effect of commercially pure titanium surfaces blasted with TiO2 particles on the biological responses of cells derived from human mandibular bone. The morphology and attachment of those cells were investigated on turned titanium surfaces (control) and surfaces blasted with 45 microns (standard), 45-63 microns, and 63-90 microns TiO2 particles. The surfaces were analyzed in a scanning electron microscope. Based on surface analyses reported elsewhere, the turned samples had the smoothest surfaces and the roughest were those blasted with the largest particles (63-90 microns). The cell profile areas were measured using a semi-automatic interactive image analyzer. The attachment was determined as a ratio of the area of cell profiles and the total micrograph area and was expressed as percentage of attachment. Morphologically, the cells were heterogeneous. In general, the cells had spread well on all titanium surfaces, indicating good attachment to both smooth and rough surfaces. After 1, 3 and 6 h, the percentage of cell attachment did not differ significantly between the surfaces blasted with 63-90 microns and the turned surfaces, but was significantly lower on the surfaces blasted with 45 microns or 45-63 microns particles. After 24 h the surfaces blasted with 63-90 microns particles had a higher rate of cell attachment than all the other surfaces including the controls. It is concluded that attachment and growth of cells originating from human mandibular bone in vitro, are influenced by the micro-texture of the implant surface.
Assuntos
Adesão Celular/fisiologia , Osteoblastos/fisiologia , Titânio/química , Células Cultivadas , Polimento Dentário , Humanos , Mandíbula/citologia , Teste de Materiais , Microscopia Eletrônica de Varredura , Propriedades de Superfície , UltrassomRESUMO
The synthesis of the 1-amino derivative of (2R,4R)-4-aminopyrrolidine-2,4-dicarboxylic acid (1-amino-APDC), a selective metabotropic glutamate ligand, is disclosed. This compound acts as a partial agonist of the group II mGluRs and shows pronounced neuroprotective properties in the NMDA model of cell toxicity.
Assuntos
Fármacos Neuroprotetores/farmacologia , Prolina/análogos & derivados , Receptores de Glutamato Metabotrópico/agonistas , Animais , Células CHO , Morte Celular , Cricetinae , Agonistas de Aminoácidos Excitatórios/síntese química , Agonistas de Aminoácidos Excitatórios/farmacologia , Camundongos , N-Metilaspartato/toxicidade , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/síntese química , Prolina/síntese química , Prolina/farmacologiaRESUMO
Estrogens affect longitudinal bone growth through their action on endochondral bone formation. Two estrogen receptors are known, the classical estrogen receptor-alpha (ER alpha), newly demonstrated in human growth plate cartilage, and a recently cloned estrogen receptor-beta (ER beta). The present study aimed to localize a possible expression of ER beta protein in human growth plates. Tissue samples were obtained from tibial and femoral growth plates in four female pubertal patients undergoing epiphyseal surgery. Immunohistochemistry, using two different ER beta-specific antibodies, demonstrated positive staining for ER beta in hypertrophic epiphyseal chondrocytes from all patients. No staining was noted in resting or proliferative chondrocytes. These data suggest that in addition to ER alpha, human epiphyseal chondrocytes also express ER beta. The physiological role of ER beta in the regulation of longitudinal bone growth in humans remains to be elucidated.
Assuntos
Lâmina de Crescimento/química , Receptores de Estrogênio/análise , Adolescente , Especificidade de Anticorpos , Criança , Receptor beta de Estrogênio , Feminino , Humanos , Imuno-Histoquímica , Receptores de Estrogênio/imunologiaRESUMO
We stably transfected human kidney embryonic 293 cells with the rat neuronal nicotinic acetylcholine receptor (nAChR) alpha3 and beta4 subunit genes. This new cell line, KXalpha3 beta4R2, expresses a high level of the alpha3/beta4 receptor subtype, which binds (+/-)- [3H]epibatidine with a Kd value of 304+/-16 pM and a Bmax value of 8942 +/- 115 fmol/mg protein. Comparison of nicotinic drugs in competing for alpha3/beta4 receptor binding sites in this cell line and the binding sites in rat forebrain (predominantly alpha4/beta2 receptors) revealed marked differences in their Ki values, but similar rank orders of potency for agonists were observed, with the exception of anatoxin-A. The affinity of the competitive antagonist dihydro-beta-erythroidine is >7000 times higher at alpha4/beta2 receptors in rat forebrain than at the alpha3/beta4 receptors in these cells. The alpha3/beta4 nAChRs expressed in this cell line are functional, and in response to nicotinic agonists, 86Rb+ efflux was increased to levels 8-10 times the basal levels. Acetylcholine, (-)-nicotine, cytisine, carbachol, and (+/-)-epibatidine all stimulated 86Rb+ efflux, which was blocked by mecamylamine. The EC50 values for acetylcholine and (-)-nicotine to stimulate 86Rb+ effluxes were 114 +/- 24 and 28 +/- 4 microM, respectively. The rank order of potency of nicotinic antagonists in blocking the function of this alpha3/beta4 receptor was mecamylamine > d-tubocurarine > dihydro-beta-erythroidine > hexamethonium. Mecamylamine, d-tubocurarine, and hexamethonium blocked the function by a noncompetitive mechanism, whereas dihydro-beta-erythroidine blocked the function competitively. The KXalpha3 beta4R2 cell line should prove to be a very useful model for studying this subtype of nAChRs.