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1.
J Physiol Pharmacol ; 71(3)2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32991313

RESUMO

Inflammatory mediators - chitotriosidase-1 (CHIT1) and leukocyte elastase (LE) - were analyzed in human seminal plasma in relation to total antioxidative status (TAS) and pro-inflammatory markers IL-1ß and IL-6. Samples collected from 34 males who were part of infertile couples were divided into normozoospermic (N; n = 12, without symptoms of inflammation), oligozoospermic (O; n = 11) and teratozoospermic (T; n = 11) groups. significant differences were observed only in CHIT1 concentration between N and O samples. However, a higher mean LE concentration was also observed in O and T patients (3.7-times and 900-times, respectively) compared with the N group. in IL-1ß and IL-6 concentrations, an upward trend was observed from N, through O, up to the T group. The positive correlation between the concentration of IL-1ß and the activity and specific activity of CHIT11 as well as the moderate negative correlation between concentrations of IL-1ß and CHIT1 may suggest that elevated CHIT11 levels appeared in early stages of inflammation before the increase in IL-1ß concentrations, or remained stable even after the levels of cytokine decreased. The above seem to confirm the role of CHIT1 in the manifestation of 'silent' inflammation at a very early stage. To conclude, CHIT1 concentration appears to be an interesting biomarker that signals the presence of possible 'silent' inflammation accompanying oligozoospermia. We cannot draw such conclusions regarding LE concentration, because, although we observed differences in the mean values and medians between analyzed groups, they were not significant. The utility of CHIT1 in the follow-up of oligozoospermia-associated 'silent' subclinical inflammation is promising, but further studies on a larger patient test set are required.


Assuntos
Hexosaminidases/análise , Mediadores da Inflamação/análise , Inflamação/enzimologia , Elastase de Leucócito/análise , Oligospermia/enzimologia , Sêmen/enzimologia , Adulto , Biomarcadores/análise , Estudos de Casos e Controles , Humanos , Inflamação/diagnóstico , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-Idade , Oligospermia/diagnóstico , Oligospermia/fisiopatologia , Projetos Piloto , Valor Preditivo dos Testes
2.
J Physiol Pharmacol ; 70(3)2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31539881

RESUMO

In the XXIst century in highly developed countries, progressively decreasing male reproductive potential is indicated. In recent years epidemiological studies indicate the deterioration of semen parameters: reduction of ejaculate volume, sperm count, and mobility, as well as abnormalities in their morphology. Male infertility can result from many different agents, such as: anatomical or genetic abnormalities, systemic or neurological diseases, infections, trauma, iatrogenic injury, gonadotoxins and development of sperm antibodies and lifestyle (especially obesity, heat and tobacco smoking). It is well documented that adverse changes in male fertility also seem to be associated with environmental exposure to different substances, especially endocrine active factors, known as xenoestrogens, and among these metal ions, known as metalloestrogens, are very important. The role of some metalloestrogens in various diseases, both in women and men, is known and particularly well-proven in women, but still little is known about their role in the regulation of male reproductive potential. Thus we decided to analyse the available information exploring this problem. The review was carried out using the Medline and Google Scholar databases, using the keywords: xenoestrogens, metalloestrogens, male fertility, semen quality, male reproductive potential, mechanisms of metalloestrogen action, environmental pollution and the name of the particular metal. Articles published between 2000 - 2019 have been taken into account, including human and vertebrate animal studies and cell lines. The aim of this review is to discuss the role and mechanisms of action of fifteen metalloestrogens in the human organism, as well as in animal models, and cell cultures, paying special attention to their influence on the physiology of male reproductive health, according to the current state of knowledge. The role of certain metals in human reproduction is still poorly investigated and for some of them only single studies are available. Many factors in our daily lives have a significant impact on male fertility, therefore education is necessary on the threats and how they may be eliminated as far as possible.


Assuntos
Estrogênios/metabolismo , Metais/metabolismo , Reprodução/fisiologia , Animais , História do Século XXI , Humanos , Infertilidade Masculina/metabolismo , Infertilidade Masculina/fisiopatologia , Masculino , Saúde Reprodutiva , Espermatozoides/metabolismo , Espermatozoides/fisiologia
3.
J Physiol Pharmacol ; 68(5): 659-668, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29375040

RESUMO

Currently, in highly developed, industrialized countries male factors are identified as the primary cause of infertility in about 60% of childless couples. Standard semen analysis parameters, such as sperm morphology, number and motility, are important in predicting the fertility of large populations, but they are not sufficient to fully specify a particular donor sperm's ability to fertilize the egg. The semen also comprises components, which may also affect sperm fertilizing ability and which have thus far remained little explored: the biochemical parameters of the seminal plasma secreted by the testis, the seminiferous tubules and the prostate gland, such as: matrix metalloproteinases (MMP-2 and MMP-9) and their specific tissue inhibitors (TIMP-1 and TIMP-2). We highlight the need for a better determination of prooxidant-antioxidant balance parameters such as: melatonin, advanced oxidation protein products (AOPPs) and total antioxidant capacity (TAC) in human semen when establishing the diagnostics of male subfertility or infertility. We also discuss their connection with seminal plasma metalloproteinases and their inhibitors. In particular, we believe that the cumulative and synergic effects of the sperm redox parameters on male fertility need to be better explored and we suggest that they should be studied in conjunction with other biologically active parameters of the ejaculate such as the expression of metalloproteinases and their tissue inhibitors. This will enable a better understanding of how their correlated effects impact semen condition.


Assuntos
Produtos da Oxidação Avançada de Proteínas/metabolismo , Antioxidantes/metabolismo , Fertilidade/fisiologia , Melatonina/metabolismo , Metaloproteases/biossíntese , Oxidantes/metabolismo , Animais , Antioxidantes/uso terapêutico , Humanos , Infertilidade Masculina/tratamento farmacológico , Infertilidade Masculina/metabolismo , Masculino , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo
5.
Int J Cosmet Sci ; 37(2): 187-95, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25393482

RESUMO

OBJECTIVES: Face painting in the colours of the national flags has become a mass phenomenon during international mega sporting events. Face paints, belonging to the group of lipophilic decorative cosmetics, pose an analytical challenge, especially in the sample preparation steps to obtain sample extracts of the colouring agents of low solubility. METHODS: In the context of official cosmetics control, a sample of German flag-coloured face paints (n = 42) offered during the soccer world cup 2014 was analysed. Sample-clean-up of hydroalcoholic and dichloromethane sample extracts was conducted using preparative thin-layer chromatography (TLC). For identification, analytical TLC, spectrophotometry considering bathochromic effects, and high-performance liquid chromatography (LC) with diode array detector were applied. Nuclear magnetic resonance (NMR) spectroscopy and LC-tandem mass spectrometry (LC-MS/MS) were used in positive cases for confirmatory analysis. NMR spectroscopy was also applied to determine the identity and purity of reference substances. Risk assessment was provided using the margin of exposure (MOE) methodology. RESULTS: The prohibited red colouring agent CI 15585 (D&C Red No. 9, Pigment Red 53:1), which is carcinogenic in animals, was positively identified in 40% of the analysed samples. Per face painting event, about 0.04 mg kg(-1) bw (adult) or 0.11 mg kg(-1) bw (child) of CI 15585 is systemically absorbed. Assuming an annual use of five times (adult) or 20 times (child), the exposure would be 5.8E-04 mg kg(-1) bw per day (adult) or 5.8E-03 mg kg(-1) bw per day (child). The MOE in these worst-case scenarios would be 6871 (adult) and 695 (child). Because the mechanism of CI 15585 is non-genotoxic and the MOE is higher than a safety factor of 100, CI 15585 does not pose a serious health risk to the consumer, but should be avoided for reasons of precautionary public health protection. CONCLUSION: An analytical strategy to determine colouring agents in face paints was developed and non-compliance with the European Union (EU) cosmetic products regulation in a considerable number of products was detected. An increased control frequency especially at the points of entry into the EU is recommended.


Assuntos
Corantes/análise , Corantes/toxicidade , Cosméticos , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Face , Alemanha , Humanos , Espectroscopia de Ressonância Magnética , Medição de Risco , Espectrometria de Massas em Tandem
6.
Andrologia ; 46(10): 1200-2, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24386970

RESUMO

The aim of our pilot study was to check whether the differences in IgA secretory component (SC) sialylation are associated with leucocytospermia. In normozoospermic and leucocytospermic seminal plasmas, 78-kDa and 63-kDa SC immunoreactive bands were observed. The SC sialylation was analysed by lectin blotting, using sialo-specific lectins MAA (Maackia amurensis agglutinin) and SNA (Sambucus nigra agglutinin). Specific reactivity of 63-kDa SC with MAA and SNA was higher than 78-kDa SC in both analysed seminal groups. The analysis of seminal SC sialylation might be a valuable diagnosis tools for the evaluation of fertility problems related with leucocytospermia.


Assuntos
Imunoglobulina A/metabolismo , Infertilidade Masculina/metabolismo , Leucócitos/metabolismo , Componente Secretório/metabolismo , Sêmen/metabolismo , Adulto , Humanos , Lectinas/metabolismo , Masculino , Pessoa de Meia-Idade , Projetos Piloto
7.
Cell Death Differ ; 13(10): 1631-40, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16888646

RESUMO

Members of the Bcl-2 protein family control the intrinsic apoptosis pathway. To evaluate the importance of this family in vertebrate development, we investigated it in the zebrafish (Danio rerio). We found that the zebrafish genome encodes structural and functional homologs of most mammalian Bcl-2 family members, including multi-Bcl-2-homology (BH) domain proteins and BH3-only proteins. Apoptosis induction by gamma-irradiation required zBax1 and zPuma, and could be prevented by overexpression of homologs of prosurvival Bcl-2 family members. Surprisingly, zebrafish Bax2 (zBax2) was homologous to mammalian Bax by sequence and synteny, yet demonstrated functional conservation with human Bak. Morpholino knockdown of both zMcl-1a and zMcl-1b revealed their critical role in early embryonic zebrafish development, and in the modulation of apoptosis activation through the extrinsic pathway. These data indicate substantial functional similarity between zebrafish and mammalian Bcl-2 family members, and establish the zebrafish as a relevant model for studying the intrinsic apoptosis pathway.


Assuntos
Genes bcl-2 , Peixe-Zebra/genética , Animais , Apoptose/genética , Apoptose/efeitos da radiação , Sequência de Bases , Raios gama , Regulação da Expressão Gênica no Desenvolvimento , Mamíferos/genética , Família Multigênica , Oligodesoxirribonucleotídeos Antissenso/genética , Filogenia , Interferência de RNA , Peixe-Zebra/embriologia
8.
Cell Death Differ ; 13(10): 1619-30, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16888647

RESUMO

The mammalian extrinsic apoptosis pathway is triggered by Fas ligand (FasL) and Apo2 ligand/tumor necrosis factor (TNF)-related apoptosis-inducing ligand (Apo2L/TRAIL). Ligand binding to cognate receptors activates initiator caspases directly in a death-inducing signaling complex. In Drosophila, TNF ligand binding activates initiator caspases indirectly, through JNK. We characterized the extrinsic pathway in zebrafish to determine how it operates in a nonmammalian vertebrate. We identified homologs of FasL and Apo2L/TRAIL, their receptors, and other components of the cell death machinery. Studies with three Apo2L/TRAIL homologs demonstrated that they bind the receptors zHDR (previously linked to hematopoiesis) and ovarian TNFR (zOTR). Ectopic expression of these ligands during embryogenesis induced apoptosis in erythroblasts and notochord cells. Inhibition of zHDR, zOTR, the adaptor zFADD, or caspase-8-like proteases blocked ligand-induced apoptosis, as did antiapoptotic Bcl-2 family members. Thus, the extrinsic apoptosis pathway in zebrafish closely resembles its mammalian counterpart and cooperates with the intrinsic pathway to trigger tissue-specific apoptosis during embryogenesis in response to ectopic Apo2L/TRAIL expression.


Assuntos
Apoptose/fisiologia , Peixe-Zebra/embriologia , Animais , Apoptose/genética , Regulação da Expressão Gênica no Desenvolvimento , Hematopoese , Ligantes , Notocorda/citologia , Transdução de Sinais , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
9.
Caries Res ; 37(2): 79-84, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12652044

RESUMO

This study was aimed at determining whether dental caries is associated with induction of the systemic immune system or cytokine response. For this purpose, 85 children from Den Pasar, Bali, Indonesia, aged 6-7 years, were examined clinically and blood plasma was obtained via finger puncture. The concentrations of the acute-phase protein alpha(1)-acid glycoprotein (AGP), total IgG and the specific IgG and IgM immunoglobulins against Streptococcus mutans were determined. Immunoelectrophoresis was used for the determination of the AGP concentration and ELISA for IgG and IgM detection. The mean dmft of the whole group was 8.8 +/- 2.9, the mean number of infected pulps was 3.9 +/- 2.2 and the mean number of abscesses was 0.5 +/- 0.8. The plasma concentration of AGP ranged between 0.13 and 1.6 mg/ml serum (mean 0.86 +/- 0.26 mg/ml). Stepwise regression analysis revealed that the concentration of IgG against S. mutans (log-transformed) was significantly correlated with dmft (adjusted r(2) = 0.083, standardized beta coefficient = 0.31, p = 0.008). When the concentration AGP was included in the model the correlation improved significantly (for IgG: adjusted r(2) = 0.157, standardised beta coefficient = 0.36, p = 0.002; for AGP: beta coefficient = -0.30, p = 0.009). The results suggest a relationship between caries and systemic parameters of inflammation. On the basis of this, severe caries might have consequences on the general health of the subject.


Assuntos
Cárie Dentária/sangue , Imunoglobulina G/sangue , alfa-Macroglobulinas/análise , Abscesso/sangue , Anticorpos Antibacterianos/sangue , Criança , Índice CPO , Cárie Dentária/imunologia , Fístula Dentária/sangue , Exposição da Polpa Dentária/sangue , Feminino , Humanos , Imunoglobulina M/sangue , Modelos Lineares , Masculino , Análise de Regressão , Estatísticas não Paramétricas , Streptococcus mutans/imunologia
10.
Mol Biol Cell ; 12(2): 449-62, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11179427

RESUMO

In bovine adrenal medullary cells synergistically acting type 1 and type 2 angiotensin II (AII) receptors activate the fibroblast growth factor-2 (FGF-2) gene through a unique AII-responsive promoter element. Both the type 1 and type 2 AII receptors and the downstream cyclic adenosine 1',3'-monophosphate- and protein kinase C-dependent signaling pathways activate the FGF-2 promoter through a novel signal-transducing mechanism. This mechanism, which we have named integrative nuclear FGF receptor-1 signaling, involves the nuclear translocation of FGF receptor-1 and its subsequent transactivation of the AII-responsive element in the FGF-2 promoter.


Assuntos
Núcleo Celular/metabolismo , Fator 2 de Crescimento de Fibroblastos/genética , Receptores de Angiotensina/metabolismo , Transdução de Sinais , Medula Suprarrenal/citologia , Medula Suprarrenal/metabolismo , Angiotensina II/análogos & derivados , Angiotensina II/farmacologia , Animais , Sítios de Ligação , Bovinos , Núcleo Celular/genética , Células Cultivadas , Pegada de DNA , Desoxirribonuclease I/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Imidazóis/farmacologia , Regiões Promotoras Genéticas , Piridinas/farmacologia , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Elementos de Resposta/fisiologia , Transativadores/metabolismo , Tirosina/metabolismo
11.
Ginekol Pol ; 71(4): 298-303, 2000 Apr.
Artigo em Polonês | MEDLINE | ID: mdl-10860263

RESUMO

During uterus contractions detaching of amino-chorionic layer from uterus wall occurs and released fibronectin penetrates into amniotic fluid. The aim of this study was to estimate in a quantity mode the presence of fibronectin in amniotic fluid and to find the dependence between the fibronectin level in amniotic fluid and the period of time from collecting the sample to the labor. We wanted also to find the dependence between fibronectin level in amniotic fluid and duration of pregnancy, preterm rupture of amniotic membranes, patients' age, parity and number of deliveries. We analysed 86 pregnant women where we estimated the fibronectin level in specimens of amniotic fluid. During carrying out the experiment we noted that fibronectin is present in amniotic fluid and can be identified in a quantity mode. We have proved dependence between fibronectin level in amniotic fluid and the period of time from collecting the sample, up to the delivery. Fibronectin level in amniotic fluid in pregnancies uncomplicated with premature delivery was on the average 350 mg/ml. Increase of fibronectin in amniotic fluid above 700 mg/ml points at detaching of amino-chorionic layer and the occurrence of unavoidable preterm labor at the time no longer than 24 hours. Fibronectin level in amniotic fluid doesn't depend of pregnancy duration, preterm rupture of amniotic membranes.


Assuntos
Líquido Amniótico/química , Ruptura Prematura de Membranas Fetais/diagnóstico , Fibronectinas/análise , Complicações na Gravidez , Adulto , Anticorpos Monoclonais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Gravidez , Índice de Gravidade de Doença
12.
Mol Biol Cell ; 9(8): 2269-85, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9693381

RESUMO

Induction of the fibroblast growth factor-2 (FGF-2) gene and the consequent accumulation of FGF-2 in the nucleus are operative events in mitotic activation and hypertrophy of human astrocytes. In the brain, these events are associated with cellular degeneration and may reflect release of the FGF-2 gene from cell contact inhibition. We used cultures of human astrocytes to examine whether expression of FGF-2 is also controlled by soluble growth factors. Treatment of subconfluent astrocytes with interleukin-1beta, epidermal or platelet-derived growth factors, 18-kDa FGF-2, or serum or direct stimulation of protein kinase C (PKC) with phorbol 12-myristate 13-acetate or adenylate cyclase with forskolin increased the levels of 18-, 22-, and 24-kDa FGF-2 isoforms and FGF-2 mRNA. Transfection of FGF-2 promoter-luciferase constructs identified a unique -555/-513 bp growth factor-responsive element (GFRE) that confers high basal promoter activity and activation by growth factors to a downstream promoter region. It also identified a separate region (-624/-556 bp) essential for PKC and cAMP stimulation. DNA-protein binding assays indicated that novel cis-acting elements and trans-acting factors mediate activation of the FGF-2 gene. Southwestern analysis identified 40-, 50-, 60-, and 100-kDa GFRE-binding proteins and 165-, 112-, and 90-kDa proteins that interacted with the PKC/cAMP-responsive region. The GFRE and the element essential for PKC and cAMP stimulation overlap with the region that mediates cell contact inhibition of the FGF-2 promoter. The results show a two-stage regulation of the FGF-2 gene: 1) an initial induction by reduced cell contact, and 2) further activation by growth factors or the PKC-signaling pathway. The hierarchic regulation of the FGF-2 gene promoter by cell density and growth factors or PKC reflects a two-stage activation of protein binding to the GFRE and to the PKC/cAMP-responsive region, respectively.


Assuntos
Astrócitos/metabolismo , Fator 2 de Crescimento de Fibroblastos/genética , Regulação da Expressão Gênica , Plasticidade Neuronal/fisiologia , Regiões Promotoras Genéticas , Transcrição Gênica , Astrócitos/citologia , Astrócitos/fisiologia , Sequência de Bases , Sítios de Ligação , Encéfalo/citologia , Encéfalo/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Colforsina/farmacologia , Proteínas de Ligação a DNA/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Fator 2 de Crescimento de Fibroblastos/biossíntese , Fator 2 de Crescimento de Fibroblastos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-1/farmacologia , Luciferases/biossíntese , Mitose , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/farmacologia , Oligonucleotídeos Antissenso/farmacologia , Reação em Cadeia da Polimerase , Proteínas Recombinantes de Fusão/biossíntese , Acetato de Tetradecanoilforbol/farmacologia , Transcrição Gênica/efeitos dos fármacos , Transfecção
13.
Brain Res Mol Brain Res ; 55(2): 293-305, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9582440

RESUMO

FGF-2, a mitogenic/neurotrophic protein, controls the development and plasticity of many types of neural cells. In neural crest-derived adrenal pheochromatocytes, induction of FGF-2 coincides with the establishment of functional innervation and is reproduced in vitro by stimulating acetylcholine receptors (AChR). The mechanisms by which AChR activate the FGF-2 gene were examined in cultured bovine adrenal medullary chromaffin (BAMC) cells in which AChR induce expression and nuclear accumulation of growth-promoting FGF-2 and FGF-2 receptors. Carbachol or nicotine increased expression of transfected FGF-2 gene promoter-luciferase constructs and were more potent than the muscarinic agonist ABMCB. Deletion analysis has identified a unique -555/-512 bp element that confers AChR stimulation and basal activity to the downstream FGF-2 promoter, and a separate protein kinase C/cAMP-responsive sequence (-625/-555 bp). Stimulation of AChR increased in vitro formation of protein complexes with the AChR-responsive element which were not displaced by target oligonucleotides for common trans-activators. Southwestern analysis identified 50-55, 125, 140 and 170 kDa proteins that interact with the AChR-responsive element in a manner stimulated by AChR. Nicotine increased tyrosine phosphorylation of cytoplasmic and nuclear proteins, including 50-55 kDa promoter-binding factors. Activation of the FGF-2 promoter was reduced by genistein. Thus, nicotinic AChR activate the FGF-2 gene via a new signaling mechanism separate from the cAMP/PKC pathways. It utilizes tyrosine phosphorylation and interaction of trans-activating factors with a novel cis-acting element. It offers a new pathway through which trans-synaptic signals may control neural development and plasticity.


Assuntos
Regiões 5' não Traduzidas/fisiologia , Fator 2 de Crescimento de Fibroblastos/genética , Plasticidade Neuronal/genética , Receptores Nicotínicos/fisiologia , Sinapses/fisiologia , Ativação Transcricional , Tirosina/metabolismo , Glândulas Suprarrenais/citologia , Animais , Bovinos , Diferenciação Celular/genética , Células Cultivadas , Células Cromafins , AMP Cíclico/fisiologia , Fosforilação , Regiões Promotoras Genéticas/fisiologia , Ligação Proteica/genética , Proteína Quinase C/fisiologia
14.
Proc Natl Acad Sci U S A ; 93(6): 2470-5, 1996 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-8637898

RESUMO

Expression of mitogenic basic fibroblast growth factor (bFGF) in the central nervous system is inhibited by direct cell contact and is implicated in reactive and neoplastic transformation of astrocytes. The molecular mechanisms controlling expression of bFGF were examined in cultures of human astrocytes. Cell-density-dependent depletion of bFGF mRNA levels parallels changes in bFGF gene protein. Regulation of transcription of a bFGF luciferase reporter gene containing an upstream region (bp -1800 to +314) of the bFGF gene promoter mimicks the density-dependent regulation of the endogenous bFGF gene in transfected astrocytes. Deletion analysis has identified a fragment (bp -650 to -513) and sequences further downstream (bp -274 to +314) as the regions required for the regulation of bFGF gene activity by cell density. Unlike in astrocytes, changing the cell density of glioma cell cultures does not affect the levels of bFGF protein and mRNA. bFGF luciferase constructs were expressed at the same level in high- or low-density cultures of glioma cells, indicating altered regulation of the bFGF gene promoter. Electrophoretic mobility shift assays showed binding of nuclear proteins to a fragment of bFGF gene promoter from bp -650 to -453. This binding was abolished by a deletion of the upstream cell-density-responsive region (bp -650 to -512). Binding was observed with nuclear extracts from subconfluent astrocytes but was reduced in extracts from confluent astrocytes. Our results indicate that induction of bFGF in astrocytes upon reduction of cell density is mediated transcriptionally by positive trans-acting factors interacting with bFGF promoter. In contrast, nuclear proteins from glioma cells bind to the promoter region from bp -650 to -453 independent of cell density. Thus, the constitutive binding of trans-acting factor(s) to the region of the bFGF promoter from bp -650 to -453 may be responsible for the continuous expression of bFGF that leads to the uncontrolled growth of glioma cells.


Assuntos
Astrócitos/fisiologia , Contagem de Células , Fator 2 de Crescimento de Fibroblastos/genética , Regiões Promotoras Genéticas , Células Cultivadas , Criança , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Histonas/genética , Humanos , Masculino , Proteínas Nucleares/metabolismo , RNA Mensageiro/genética , Ativação Transcricional
15.
Am J Occup Ther ; 42(6): 395-8, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3394792

RESUMO

Thermoplastics are useful for many types of splints, but most splints made from them position the hand statically and have the disadvantage of limiting the sensory feedback that occurs during normal use and movement. Neoprene is an alternative to thermoplastics when dynamic mobility in splinting is the goal. Neoprene is soft, stretchable, lightweight, durable, nontoxic, machine-washable, and has a good memory. The TASS uses the Bobaths' key point of forearm supination and thumb abduction to position the upper extremity more functionally without the patient having to use effort. Thus sensory feedback can occur while the limb is moving within a prescribed range. The TASS can be used as an extra "hand" during the occupational therapy treatment session, or it can be applied immediately after treatment to continue to facilitate functional positioning of the limb.


Assuntos
Neopreno , Doenças Neuromusculares/reabilitação , Polienos , Contenções , Polegar/fisiopatologia , Criança , Antebraço/fisiopatologia , Mãos/fisiopatologia , Humanos , Espasticidade Muscular/reabilitação , Terapia Ocupacional/instrumentação , Supinação
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