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1.
Clin Genet ; 92(3): 306-317, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28255985

RESUMO

BACKGROUND: Tyrosinemia type II, also known as Richner-Hanhart Syndrome, is an extremely rare autosomal recessive disorder, caused by mutations in the gene encoding hepatic cytosolic tyrosine aminotransferase, leading to the accumulation of tyrosine and its metabolites which cause ocular and skin lesions, that may be accompanied by neurological manifestations, mostly intellectual disability. AIMS: To update disease-causing mutations and current clinical knowledge of the disease. MATERIALS AND METHODS: Genetic and clinical information were obtained from a collection of both unreported and previously reported cases. RESULTS: We report 106 families, represented by 143 individuals, carrying a total of 36 genetic variants, 11 of them not previously known to be associated with the disease. Variants include 3 large deletions, 21 non-synonymous and 5 nonsense amino-acid changes, 5 frameshifts and 2 splice variants. We also report 5 patients from Gran Canaria, representing the largest known group of unrelated families sharing the same P406L mutation. CONCLUSIONS: Data analysis did not reveal a genotype-phenotype correlation, but stressed the need of early diagnosis: All patients improved the oculocutaneous lesions after dietary treatment but neurological symptoms prevailed. The discovery of founder mutations in isolated populations, and the benefits of early intervention, should increase diagnostic awareness in newborns.


Assuntos
Efeito Fundador , Estudos de Associação Genética , Mutação , Fenótipo , Tirosinemias/diagnóstico , Tirosinemias/genética , Adolescente , Idade de Início , Alelos , Criança , Pré-Escolar , Feminino , Loci Gênicos , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Linhagem , Polimorfismo de Nucleotídeo Único , Tirosina Transaminase/genética , Tirosinemias/dietoterapia , Adulto Jovem
2.
Anaesthesist ; 64(12): 927-936, 2015 12.
Artigo em Alemão | MEDLINE | ID: mdl-26497656

RESUMO

BACKGROUND: In contrast to the widespread practice in life-threatening emergencies, delegation of medical pain therapy to paramedics by the medical director  of Emergency Medical Services, EMS, are still the exception in Germany. This is due to the fact that in non-life-threatening situations, the expected benefit and potential side effects of drug therapy have to be carefully weighed. In addition, in Germany federal law generally restricts the administration of opiates to physicians. METHODS: In 2011 the medical directors of EMS in the German state of Rhineland- Palatinate (4 million inhabitants) developed and implemented a standard operating procedure (SOP) for paramedics related to the prehospital parenteral administration of paracetamol for patients with isolated limb trauma. After a 2 h training session and examination, paramedics were authorized to administer 1 g of paracetamol to patients with a pain score > 5 points on an 11-point numerical rating scale (NRS). For purposes of quality management, every administration of paracetamol had to be prospectively documented on a specific electronic mission form. RESULTS: A total of 416 mission forms could be analyzed. After administration of paracetamol the median NRS score decreased from 8 points (interquartile range: 6; 8) to 4 points (interquartile range: 3; 7). In 51.2 % of the patients the pain intensity was reduced by at least 3 NRS points and in 50.5 % of the patients the NRS was less than 5 points after treatment. The extent of pain reduction was positively correlated with the initial NRS value (r = 0.31, p < 0.0001). No serious side effects were noted. The percentage of patients with an initial heart rate > 100/min declined from 14.6 % to 5.2 % after the administration of paracetamol (p < 0.0001), 18.7 % of the patients received paracetamol for trauma not related to the extremities and 7 % of the patients for nontraumatic pain. An emergency physician was involved in 50 % of the EMS missions and 98.6 % of the patients were transported to a hospital for further diagnostics and treatment. CONCLUSION: The prehospital intravenous administration of paracetamol by paramedics to patients with limb trauma is simple, safe and in 50 % of the patients effective in achieving a NRS value < 5; however, further improvements in prehospital pain therapy initiated by paramedics are desirable, especially in patients with an initial NRS value > 7.

3.
Nat Genet ; 13(2): 230-2, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8640233

RESUMO

Haploinsufficiency for SOX9 has recently been identified as the cause for both campomelic dysplasia (CD), a human skeletal malformation syndrome, and the associated autosomal XY sex reversal. SOX9 contains a putative DNA-binding motif known as the high-mobility group (HMG) domain characterizing a whole class of transcription factors. We show in cell transfection experiments that SOX9 can transactivate transcription from a reporter plasmid through the motif AACAAAG, a sequence recognized by other HMG domain transcription factors. By fusing all or part of SOX9 to the DNA-binding domain of yeast GAL4, the transactivating function was mapped to a transcription activation (TA) domain at the C terminus of SOX9. This non-acidic TA domain is evolutionarily conserved and rich in proline, glutamine and serine. With one exception, all SOX9 nonsense and frame shift mutations described so far in CD/sex reversal patients lead to truncation of the TA domain, suggesting that impairment of gonadal and skeletal development in these cases results, at least in part, from loss of transactivation of genes downstream of SOX9.


Assuntos
Transtornos do Desenvolvimento Sexual , Proteínas de Grupo de Alta Mobilidade/genética , Proteínas de Saccharomyces cerevisiae , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Extratos Celulares , Células Cultivadas , Sequência Conservada , Proteínas de Ligação a DNA , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação da Expressão Gênica , Haplorrinos , Proteínas de Grupo de Alta Mobilidade/metabolismo , Humanos , Rim/citologia , Dados de Sequência Molecular , Mutação , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Transcrição SOX9 , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/metabolismo , Transcrição Gênica , Transfecção
4.
Genet Couns ; 22(1): 49-53, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21614988

RESUMO

Campomelic dysplasia (CD, MIM 114290) is a rare, often lethal, dominantly inherited, congenital skeletal dysplasia, associated with male-to-female autosomal sex reversal and due to de novo mutations of the SOX9 gene, a tissue-specific transcription factor gene involved both in skeletogenesis and male sexual differentiation. Here we report on a 4 months-old 46,XY sex reversed infant with typical clinical features for CD due to a novel mutation of the SOX9 gene, Q401X, leading to synthesis of a truncated SOX9 protein that completely lacks the C-terminal transactivation domain.


Assuntos
Anormalidades Múltiplas/genética , Displasia Campomélica/genética , Aberrações Cromossômicas , Códon sem Sentido/genética , Disgenesia Gonadal 46 XY/genética , Fatores de Transcrição SOX9/genética , Anormalidades Múltiplas/diagnóstico , Displasia Campomélica/diagnóstico , Análise Mutacional de DNA , Evolução Fatal , Feminino , Triagem de Portadores Genéticos , Disgenesia Gonadal 46 XY/diagnóstico , Humanos , Lactente , Recém-Nascido , Cariotipagem , Masculino , Gravidez , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico , Síndrome do Desconforto Respiratório do Recém-Nascido/genética
5.
Anaesthesist ; 60(8): 751-8, 2011 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-21818523

RESUMO

Up-to-date management of medical emergencies implies primarily that definitive diagnoses and treatment are performed in a timely manner. These claims have been reconfirmed in 2007 by the leading German language medical associations in their "White Paper on Emergency Treatment". To actually realize the demands described in this paper a timely, transsectoral and close collaboration of all involved organizations is mandatory. To illustrate this race against cell death the phrase relay of survival is proposed and launched to replace the hitherto used but rigid concept of chain of survival. The tasks of each member of this relay of survival are critically scrutinized one after the other from a patient perspective. The paper presents tangible recommendations for improving the respective individual performance as well as, in particular, the cooperation and coordination between the team members which is comparable to handing over the baton in a relay race.


Assuntos
Serviços Médicos de Emergência/organização & administração , Competência Clínica , Comunicação , Alemanha , Guias como Assunto , Hospitais , Humanos , Administração dos Cuidados ao Paciente , Equipe de Assistência ao Paciente , Qualidade da Assistência à Saúde , Sobrevida , Centros de Traumatologia/organização & administração
6.
Hum Reprod ; 25(10): 2637-46, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20685758

RESUMO

BACKGROUND: XY gonadal dysgenesis (XY-GD) is a heterogeneous disorder characterized by failure of testicular development despite a normal male karyotype. Non-syndromic and syndromic forms can be delineated. Currently, only a minority of cases can be explained by gene mutations. METHODS: The aim of this study was to detect microdeletions and duplications by using high-resolution Agilent oligonucleotide arrays in a cohort of 87 patients with syndromic or non-syndromic 46,XY-GD. RESULTS: In 26 patients, we identified gains or losses in regions including genes involved in XY-GD (DMRT1, SOX9, DAX1) or in regions, which have not been described as polymorphic copy number variants (CNVs). CONCLUSIONS: This study shows that array comparative genomic hybridization (CGH) analysis is a useful tool for the molecular diagnosis of XY-GD as well as for the identification of potential candidate genes involved in male sexual development.


Assuntos
Loci Gênicos , Disgenesia Gonadal 46 XY/diagnóstico , Disgenesia Gonadal 46 XY/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos de Coortes , Receptor Nuclear Órfão DAX-1/genética , Feminino , Genes Duplicados , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Transcrição SOX9/genética , Deleção de Sequência , Fatores de Transcrição/genética , Adulto Jovem
7.
Scand J Immunol ; 72(5): 388-95, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21039733

RESUMO

Natural killer (NK) cells are innate immune cells involved in antiviral defence and tumour surveillance. To fulfil these tasks, NK cells make use of two major effector functions, cytokine and chemokine release and cytotoxicity. In addition, NK cells proliferate in response to cytokines such as IL-2. NK cells possess a large array of activating and inhibitory receptors and their activation demands a complex crosstalk between those receptors. The signalling pathways leading to NK-cell activation are a field of intensive research. The first clue for signal specificity was provided by studies showing that a pathway leading to NF-κB activation selectively induces cytokine release, but is dispensable for cytotoxicity. Here, we demonstrate that in human NK cells caspase activity is required for the upregulation of select activation markers and IFN-γ and TNF production, but not for cytotoxicity. Interestingly, caspases have previously been linked in T cells to the same mechanism of NF-κB induction that is active in NK cells. Moreover, we provide evidence that caspases are involved in IL-2-induced proliferation. Thus, our data provide the basis for a novel approach using caspase inhibitors to generate cytotoxic NK cells, while simultaneously suppressing cytokine release.


Assuntos
Caspases/metabolismo , Proliferação de Células , Citocinas/metabolismo , Células Matadoras Naturais/metabolismo , Clorometilcetonas de Aminoácidos/farmacologia , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Inibidores de Caspase , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Inibidores de Cisteína Proteinase/farmacologia , Ativação Enzimática/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Antígenos HLA-DR/metabolismo , Humanos , Interferon gama/metabolismo , Interleucina-2/farmacologia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Células K562 , Células Matadoras Naturais/citologia , Células Matadoras Naturais/efeitos dos fármacos , Lectinas Tipo C/metabolismo , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo
8.
J Phys Chem B ; 113(29): 9886-93, 2009 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-19569628

RESUMO

We have developed interatomic interaction parameters for Na+ and Cl- hydration using the dissociative water potential of Mahadevan and Garofalini [J. Phys. Chem. B 2007, 111, 8919] suitable for molecular dynamic simulations. Simulations were performed for small ion-water clusters Na(H2O)n+ (n=1-6) and Cl(H2O)m- (m=1-5), as well as dilute aqueous solutions of the ions in water, reproducing the structure and energies found in the literature. A simulation of an HCl molecule in water demonstrated the dissociation of the molecule. The Na+ and Cl- ion-ion interaction parameters also reproduce the energy and density of crystalline NaCl. A series of simulations of NaCl at progressively increasing temperatures from 300 to 1400 K produced solid densities varying by less than 1% from experiment.


Assuntos
Cloretos/química , Simulação por Computador , Modelos Químicos , Sódio/química , Água/química , Íons/química , Cloreto de Sódio/química , Temperatura
9.
Mol Cell Biol ; 18(11): 6653-65, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9774680

RESUMO

For proper male sexual differentiation, anti-Müllerian hormone (AMH) must be tightly regulated during embryonic development to promote regression of the Müllerian duct. However, the molecular mechanisms specifying the onset of AMH in male mammals are not yet clearly defined. A DNA-binding element for the steroidogenic factor 1 (SF-1), a member of the orphan nuclear receptor family, located in the AMH proximal promoter has recently been characterized and demonstrated as being essential for AMH gene activation. However, the requirement for a specific promoter environment for SF-1 activation as well as the presence of conserved cis DNA-binding elements in the AMH promoter suggest that SF-1 is a member of a combinatorial protein-protein and protein-DNA complex. In this study, we demonstrate that the canonical SOX-binding site within the human AMH proximal promoter can bind the transcription factor SOX9, a Sertoli cell factor closely associated with Sertoli cell differentiation and AMH expression. Transfection studies with COS-7 cells revealed that SOX9 can cooperate with SF-1 in this activation process. In vitro and in vivo protein-binding studies indicate that SOX9 and SF-1 interact directly via the SOX9 DNA-binding domain and the SF-1 C-terminal region, respectively. We propose that the two transcription factors SOX9 and SF-1 could both be involved in the expression of the AMH gene, in part as a result of their respective binding to the AMH promoter and in part because of their ability to interact with each other. Our work thus identifies SOX9 as an interaction partner of SF-1 that could be involved in the Sertoli cell-specific expression of AMH during embryogenesis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Glicoproteínas , Gônadas/crescimento & desenvolvimento , Inibidores do Crescimento/genética , Proteínas de Grupo de Alta Mobilidade/metabolismo , Hormônios Testiculares/genética , Fatores de Transcrição/metabolismo , Animais , Hormônio Antimülleriano , Células COS , Sequência Consenso/genética , Pegada de DNA , Fatores de Transcrição Fushi Tarazu , Regulação da Expressão Gênica no Desenvolvimento/genética , Proteínas de Homeodomínio , Humanos , Imuno-Histoquímica , Masculino , Proteínas Nucleares/metabolismo , Ligação Proteica/fisiologia , Receptores Citoplasmáticos e Nucleares , Proteínas Recombinantes/genética , Fatores de Transcrição SOX9 , Deleção de Sequência/genética , Homologia de Sequência do Ácido Nucleico , Diferenciação Sexual/genética , Fator Esteroidogênico 1 , Ativação Transcricional/genética , Transfecção/genética
10.
Hum Exp Toxicol ; 26(1): 37-47, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17334178

RESUMO

Crotonaldehyde, an alpha,beta-unsaturated aldehyde, and a potent alkylating agent, is present in many foods and beverages, ambient air and tobacco smoke. A previous study indicated that two metabolites, 3-hydroxy-1-methylpropylmercapturic acid (HMPMA) and 2-carboxyl-l-methylethylmercapturic acid (CMEMA), were excreted in rat urine after subcutaneous injection of crotonaldehyde. Herein, we report the development of a method based on liquid chromatography with tandem mass spectrometry (LC-MS/MS) and deuterated analytes as internal standards, for the determination of HMPMA and CMEMA in human urine. The limits of quantification of the method were 92 and 104 ng/mL for HMPMA and CMEMA, respectively. The calibration curves for both compounds were linear up to 7500 ng/mL with R2 >0.99. It was found that cigarette smokers excreted about three to five-fold more HMPMA, and only slightly elevated amounts of CMEMA, in their urine compared to nonsmokers. In smokers, we also found significant correlations between the urinary excretion levels of HMPMA (but not CMEMA) and several markers of exposure for smoking, including the daily cigarette consumption, carbon monoxide in exhaled breath, salivary cotinine, and nicotine plus five of its major metabolites in urine. Smoking cessation or switching from smoking conventional cigarettes to experimental cigarettes with lower crotonaldehyde delivery led to significant reductions of urinary HMPMA excretion, but not CMEMA excretion. Alcohol consumption did not influence either urinary HMPMA or CMEMA excretion. We conclude that HMPMA is a potentially useful biomarker for smoking-related exposure to crotonaldehyde.


Assuntos
Acetilcisteína/análogos & derivados , Aldeídos/farmacocinética , Fumar/urina , Acetilcisteína/urina , Adulto , Idoso , Consumo de Bebidas Alcoólicas/urina , Biomarcadores/urina , Calibragem , Cromatografia Líquida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem
11.
J Plant Physiol ; 196-197: 53-9, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27058428

RESUMO

When grown on a non-penetretable at a surface angle of 45°, Arabidopsis roots form wave-like structures and, in wild type rarely, but in certain mutants the tip root even may form circles. These circles are called coils. The formation of coils depends on the complex interaction of circumnutation, gravitropism and negative thigmotropism where - at least - gravitropism is intimately linked to auxin transport and signaling. The knockout mutant of patatin-related phospholipase-AI-1 (pplaI-1) is an auxin-signaling mutant which forms moderately increased numbers of coils on tilted agar plates. We tested the effects of the auxin efflux transport inhibitor NPA (1-naphthylphtalamic acid) and of the influx transport inhibitor 1-NOA (1-naphthoxyacetic acid) which both further increased root coil formation. The pPLAI-1 inhibitors HELSS (haloenol lactone suicide substrate=E-6-(bromomethylene)tetrahydro-3-(1-naphthalenyl)-2H-pyran-2-one) and ETYA (eicosatetraynoic acid) which are auxin signaling inhibitors also increased coil formation. In addition, far red light treatment increased coil formation. The results point out that a disturbance of auxin transport and signaling is one potential cause for root coils. As we show that the mutant pplaI-1 penetrates horizontal agar plates better than wild type plants root movements may help penetrating the soil.


Assuntos
Arabidopsis/genética , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/antagonistas & inibidores , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transporte Biológico , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Ácidos Indolacéticos/antagonistas & inibidores , Raios Infravermelhos , Mutação , Reguladores de Crescimento de Plantas/antagonistas & inibidores , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Transdução de Sinais
12.
J Mol Biol ; 184(3): 367-73, 1985 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-2413215

RESUMO

The tyrosine aminotransferase (TAT) gene is expressed in a tissue and developmental-specific manner. In addition, this gene is regulated by glucocorticoid and polypeptide hormones and its expression is affected when a regulatory region near the albino locus of the mouse is deleted. In order to allow studies of the molecular effects of these deletion mutations we have isolated and characterized the mouse TAT gene. The gene is 9.2 x 10(3) bases in length and consists of 12 exons which give rise to a 2.3 x 10(3) base long messenger RNA. The DNA sequence at the 5' end of the gene was determined and compared with the corresponding sequence of the rat tyrosine aminotransferase gene. The sequence comparison showed extensive homology over the entire region sequenced. In addition, DNA: DNA heteroduplex studies between the mouse and rat tyrosine aminotransferase genes revealed that this homology extends over the entire gene and its flanking sequences. The mouse tyrosine aminotransferase gene has been mapped distal to the serum esterase-1 locus on mouse chromosome 8, using a restriction fragment length polymorphism between two mouse species. Since the albino deletions are located on mouse chromosome 7, the assignment of the TAT gene to chromosome 8 suggests that a regulatory factor(s) affecting TAT gene expression acts in trans.


Assuntos
Mapeamento Cromossômico , Genes , Tirosina Transaminase/genética , Animais , Sequência de Bases , DNA/genética , Camundongos , Microscopia Eletrônica , Hibridização de Ácido Nucleico , RNA/genética , Ratos
13.
J Mol Biol ; 279(2): 449-60, 1998 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-9642049

RESUMO

Peptidyl-prolyl cis/trans isomerisation has been frequently found as a rate limiting step in the folding of proteins. In order to determine whether the nature of the amino acid preceding proline controls the probability of cis prolyl bonds in native proteins, systematic studies on the thermodynamics and kinetics of the prolyl isomerisation in the pentapeptide series Ac-Ala-Xaa-Pro-Ala-Lys-NH2 were performed. All proteinogenic amino acids were substituted in the position preceding proline. When measured by 1H-NMR and CD spectroscopy both isomers proved to be devoid of ordered structure in the whole series of the oligopeptides in aqueous solution. Thus, isomerization rates and cis/trans ratios calculated from solvent jump and 1H-NMR magnetisation transfer experiments exclusively reflect the side-chain effects of the Xaa position in the peptide series. There is a rough correlation between the cis content in the oligopeptides and the propensity of Xaa-Pro cis prolyl bonds in proteins. This correlation suggests that the prolyl bond conformation is mainly determined by local effects in proteins. The rate constants kc-->t of pentapeptides containing unionised amino acids preceding proline range from 3.2 x 10(-3) s-1 (Xaa = Ala) to 0.5 x 10(-3) s-1 (Xaa = Trp) at 4 degrees C. Proline clustering led to an isomerisation cycle indicating considerable influence on the isomerisation rates of the peptide bond conformations flanking the rotating bond. Both tyrosine and histidine specifically reduce isomerisation rates severalfold by deprotonation of their respective side-chains.


Assuntos
Prolina/química , Proteínas/química , Sequência de Aminoácidos , Dicroísmo Circular , Bases de Dados Factuais , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Ressonância Magnética , Oligopeptídeos/química , Conformação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Estereoisomerismo
14.
Mech Dev ; 91(1-2): 323-5, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10704857

RESUMO

Sex determination in mammals is controlled by various transcription factors. Following the identification of SRY on the Y chromosome, several other factors have been identified. They can normally be identified as being involved in sex determination by the identification of sex reversal mutations or deletions, functional studies, and also by male-specific expression patterns in embryos. Here, it is shown that DMRT1, recently demonstrated to be deleted in 9p monosomies associated with sex reversal, is specifically expressed during sex determination in the genital ridge of human male, but not female, embryos, similar to SRY.


Assuntos
Processos de Determinação Sexual , Fatores de Transcrição/genética , Feminino , Humanos , Masculino
15.
FEBS Lett ; 509(2): 174-6, 2001 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-11741583

RESUMO

4,5-Diaminofluorescein, a fluorescence indicator for NO, was applied to detect the release of NO from plant cells. NO production was increased within 3 min when plant cell cultures (Arabidopsis, parsley, and tobacco) were treated by cytokinin and was dose-dependent and signal-specific in that other plant hormones and inactive cytokinin analog were not effective in stimulating of NO release. The response was quenched by addition of 2-(aminoethyl)-2-thiopseudourea, an inhibitor of the animal NO synthase, and by addition of an NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-1-oxy-3-oxide. These results imply that NO may act in cytokinin signal transduction.


Assuntos
Adenina/análogos & derivados , Citocininas/farmacologia , Magnoliopsida/metabolismo , Óxido Nítrico/metabolismo , Adenina/farmacologia , Arabidopsis/citologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Compostos de Benzil , Sequestradores de Radicais Livres/farmacologia , Cinetina , Magnoliopsida/citologia , Magnoliopsida/efeitos dos fármacos , Óxido Nítrico Sintase/antagonistas & inibidores , Petroselinum/citologia , Petroselinum/efeitos dos fármacos , Petroselinum/metabolismo , Purinas , Transdução de Sinais , Nicotiana/citologia , Nicotiana/efeitos dos fármacos , Nicotiana/metabolismo , Zeatina/farmacologia
16.
FEBS Lett ; 436(1): 51-4, 1998 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-9771892

RESUMO

Kinectin has been characterized as the first known receptor for the molecular motor kinesin, which is critically involved in microtubule-based vesicle transport and membrane trafficking. Here we identify kinectin as a target for caspase-mediated proteolysis during apoptosis. Treatment of cells with diverse apoptotic stimuli including TNF, anti-Fas, anticancer drugs, gamma-radiation or ceramide leads to rapid proteolytic cleavage of the 160-kDa form of kinectin to a 120-kDa fragment. Evidence is provided that kinectin cleavage is mediated by caspase 7.


Assuntos
Caspases/metabolismo , Proteínas de Membrana , Receptores de Superfície Celular/metabolismo , Clorometilcetonas de Aminoácidos/farmacologia , Anticorpos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Caspase 7 , Caspases/efeitos dos fármacos , Caspases/genética , Sistema Livre de Células , Ceramidas/farmacologia , Cisplatino/farmacologia , Inibidores de Cisteína Proteinase/farmacologia , Daunorrubicina/farmacologia , Etoposídeo/farmacologia , Células HeLa/efeitos dos fármacos , Células HeLa/metabolismo , Células HeLa/efeitos da radiação , Humanos , Células Jurkat/efeitos dos fármacos , Células Jurkat/metabolismo , Células Jurkat/efeitos da radiação , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Receptor fas/imunologia , Receptor fas/metabolismo
17.
FEBS Lett ; 394(3): 289-94, 1996 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-8830660

RESUMO

Oligopeptides derived from the gag polyprotein (Pr55gag) of human immunodeficiency virus type 1 (HIV-1) segment were used to evaluate the extension of the putative binding region for the complex of Pr55gag and the human cytosolic peptidyl prolyl cis/trans isomerase (PPIase) 18 kDa cyclophilin (Cyp18). Five N-terminally acetylated, C-terminally amidated oligopeptides containing one (HIV-1 Gag218-224; 1), two (HIV-1 Gag218-226 and HIV-1 Gag217-224; 2 and 3, respectively), three (HIV-1 Gag217-226; 4) or four (HIV-1 Gag213-237; 5) proline residues were synthesized. Using competition experiments with a standard substrate the binding affinities to Cypl8 of the synthesized peptides were determined. The IC50 value of 184 microM for the 25-mer peptide 5 was fivefold or more lower than those of the peptides 1-4 lacking one or more prolines. Failure of competition in assays containing enzymes of other PPIase families by millimolar concentrations of 5 revealed a Cyp18 specific interaction involving the active site of the enzyme. In its far UV circular dichroism, aqueous solutions of 5 display properties of random coil conformation, but spectra were also consistent with a small contribution of proline specific secondary structures. However, a proline-rich peptide typical of forming left-handed polyproline II helices did not compete for the active site of Cypl8. The results demonstrate that the putative binding region of HIV-1 gag polyprotein has a certain degree of binding affinity to the PPIase site of Cyp18, and may add a previously unrecognized topological component to the known subsite specificity of cyclophilins.


Assuntos
Isomerases de Aminoácido/metabolismo , Proteínas de Transporte/metabolismo , Produtos do Gene gag/metabolismo , HIV-1 , Oligopeptídeos/metabolismo , Precursores de Proteínas/metabolismo , Isomerases de Aminoácido/genética , Sequência de Aminoácidos , Sítios de Ligação , Proteínas de Transporte/genética , Dicroísmo Circular , Humanos , Cinética , Dados de Sequência Molecular , Oligopeptídeos/síntese química , Peptidilprolil Isomerase , Ligação Proteica , Conformação Proteica , Proteínas Recombinantes/metabolismo
18.
Cancer Epidemiol Biomarkers Prev ; 9(4): 373-80, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10794481

RESUMO

In a field study with 69 subjects, we investigated the influence of smoking, exposure to environmental tobacco smoke (ETS), diet, and location of residence on biomarkers for polycyclic aromatic hydrocarbons (PAH), including urinary excretion of 1-hydroxypyrene and benzo[a]pyrene (BaP) adducts of hemoglobin and albumin. The self-reported smoking status and the extent of ETS exposure were verified by urinary cotinine measurements. ETS exposure was quantified by nicotine and 3-ethenylpyridine measurements on personal samplers worn by the nonsmokers over 5 or 7 days before blood and urine samples were collected. Smokers (n = 27), on average, excreted 0.346 microg/24 h 1-hydroxypyrene, whereas the corresponding value for nonsmokers (n = 42) was 0.157 microg/24 h. Average BaP adduct levels with hemoglobin and albumin were 0.105 fmol/mg and 0.042 fmol/mg, respectively, for smokers, and 0.068 fmol/mg and 0.020 fmol/mg, respectively, for nonsmokers. The differences, except for the hemoglobin adducts, were statistically significant. Of the 42 nonsmokers, 19 were classified as passive smokers. There was no significant difference in the PAH biomarkers between nonsmokers exposed to ETS and those not or rarely exposed to ETS. Total dietary BaP intake, as calculated from questionnaire data, did not correlate with any of the PAH biomarkers (r < 0.1). Subjects living in the suburbs tended to have higher BaP-protein adduct levels than subjects living in the city. Our findings suggest that diet and smoking are major sources for PAH exposure of persons not occupationally exposed to PAH, whereas the influence of ETS exposure is negligible. The lack of correlation between the dietary PAH intake and the PAH biomarkers may be due to the inaccuracy of the estimate for the dietary PAH intake.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Fumar/efeitos adversos , Poluição por Fumaça de Tabaco/efeitos adversos , Adolescente , Adulto , Idoso , Albuminas/análise , Albuminas/metabolismo , Biomarcadores/análise , Dieta , Exposição Ambiental/análise , Feminino , Hemoglobinas/análise , Hemoglobinas/metabolismo , Habitação , Humanos , Masculino , Pessoa de Meia-Idade , População Rural , Sensibilidade e Especificidade , Poluição por Fumaça de Tabaco/análise , População Urbana
19.
Am J Med Genet ; 104(3): 239-45, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11754051

RESUMO

Campomelic syndrome (or campomelic dysostosis, CD; MIM *114290) is an autosomal dominant skeletal malformation syndrome characterized by shortness and bowing of long bones, especially of the lower limbs. Additional radiological and clinical findings are 11 pairs of ribs and a bell-shaped thorax, hypoplastic scapulae, narrow iliac wings, non-mineralized thoracic pedicles, clubbed feet, Robin sequence, typical facial anomalies and tracheomalacia. The disorder is frequently lethal due to respiratory distress. Sex reversal occurs in most patients with an XY karyotype. CD is caused by heterozygous mutations in the SOX9 gene, an SRY-related gene at 17q24.3-q25.1 with pleiotropic effects on the skeletal and genital systems. In addition, cases with chromosomal rearrangements involving 17q have been described that are most likely caused by disturbing one or more cis-regulatory elements from an extended control region. Campomelia (bowed limbs) is seen in most but not all patients, defining a so-called acampomelic campomelic dysostosis (ACD). Half of the CD cases with 17q rearrangements have no or mild campomelia. Furthermore, campomelia is absent or only mildly present in a small subgroup of cases with a normal karyotype. We present a chromosomally normal boy with ACD and his clinical follow-up up to the age of 2 years, in whom a heterozygous SOX9 missense mutation (H165Y) was identified. A SOX9 missense mutation was published in two other patients with ACD. Although up to now a general genotype-phenotype correlation could not be established for CD, a correlation emerges for the ACD variant that needs further confirmation.


Assuntos
Doenças do Desenvolvimento Ósseo/patologia , Proteínas de Grupo de Alta Mobilidade/genética , Fatores de Transcrição/genética , Doenças do Desenvolvimento Ósseo/genética , Pré-Escolar , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Mutação , Mutação de Sentido Incorreto , Fatores de Transcrição SOX9
20.
Am J Med Genet ; 93(5): 421-5, 2000 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-10951468

RESUMO

Acampomelic campomelic dysplasia is a rare clinical variant of the more commonly encountered campomelic dysplasia (CMD1), characterized by absence of long bone curvature (acampomelia). We present a patient with acampomelic CMD1 with a de novo SOX9 missense mutation and report his clinical course to age one year, thereby contributing to genotype-phenotype correlation in CMD1. 2000.


Assuntos
Proteínas de Grupo de Alta Mobilidade/genética , Mutação de Sentido Incorreto , Osteocondrodisplasias/genética , Fatores de Transcrição/genética , Humanos , Lactente , Masculino , Osteocondrodisplasias/diagnóstico por imagem , Radiografia , Fatores de Transcrição SOX9
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