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1.
Arch Orthop Trauma Surg ; 138(6): 879-885, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29696363

RESUMO

INTRODUCTION: In case of distal radius fractures (DRF) the distal fragment generally displaces either dorsally or volarly. Scientific literature however, seldom differentiates between volarly and dorsally displaced DRFs when reporting results. It is no clear, if the direction of displacement has an influence on the clinical and radiological outcome. This study was intended to evaluate the influence of displacement direction in adult patients with surgically treated Colles or Smith type fractures. PATIENTS AND METHODS: After a mean follow up (FU) time of above 5 years, 50 patients who underwent open reduction and internal fixation for DRFs (25 Smith type fractures, 25 Colles type fractures) were included. Upon FU, standard X-rays and a clinical evaluation as well as evaluation scores were raised and analysed. RESULTS: Clinical evaluation showed no difference between the Colles and the Smith group. Radiologic and clinical results for the Colles group showed diminished flexion compared to the healthy wrist, decreased radial inclination and dorsal tilt during FU and progression of osteoarthritis. For the Smith group decreased grip strength compared to the healthy wrist and osteoarthritis-progression was found. For both groups there was no correlation between radiologic values, grip strength, arthrosis grading, disability of arm, shoulder and hand score and patient rated wrist evaluation score. DISCUSSION: Decreased flexion in combination with a decreased dorsopalmar tilt might hint towards a mechanical inhibition in the Colles group. Altogether, the study showed good clinical outcome with satisfactory radiological result. As all patients showed arthrosis progression, the fracture per se is to be seen as a prearthrotic factor. It still remains unclear which measures could be taken to prevent this.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/métodos , Fraturas do Rádio/cirurgia , Traumatismos do Punho/cirurgia , Articulação do Punho/cirurgia , Adulto , Idoso , Feminino , Fixação Interna de Fraturas/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade
2.
Georgian Med News ; (267): 27-34, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28726649

RESUMO

The aim of this study was to compare the concentration of inflammatory vascular markers and morphological structure of atherosclerotic plaque in symptomatic and asymptomatic patients with the stenosis of internal carotid artery (ICA). The research was carried out in 70 patients with hemodynamically significant stenosis of ICA out of which 40 (57%) were asymptomatic patients and 30 (43%) were symptomatic patients, of which 20 patients (66%) have had a stroke, or transient ischemic attack (TIA), 10 patients (33%). All the patients were indicated to carotid endarterectomy as a surgical prevention of stroke. All the patients were taken their blood for biochemical testing (T-Chol, LDL, HDL, TG, Fibrinogen, CRP and specific markers IL-4 and Lp-PLA2) early morning prior to surgery. The highest concentrations of T-Chol, LDL, HDL, CRP and Fibrinogen were measured in symptomatic patients, however, these did not feature a significant difference compared with the group of asymptomatic patients (P>0.05). Significant difference was found in IL-4 (P<0.001) and in Lp-PLA2 (P<0.001). When evaluating concentration of tracked parameters in patients with soft atherosclerotic plaque and patients with calcified atherosclerotic plaque, significant differences were found in these markers: TG (P<0.05), CRP (P<0.01), IL-4 (P<0.001) and Lp-PLA2 (P<0.001). The paper deals with higher concentrations of Lp-PLA2 in patients with a soft atherosclerotic plaque. Higher concentration of Lp-PLA2 and systemic inflammatory markers (CRP, IL-4) could be used along with ultrasonography to detect mainly asymptomatic patients who are in urgent need of surgical or endovascular treatment as a prevention of stroke.


Assuntos
1-Alquil-2-acetilglicerofosfocolina Esterase/metabolismo , Artéria Carótida Interna/enzimologia , Estenose das Carótidas/enzimologia , Placa Aterosclerótica/enzimologia , Idoso , Biomarcadores/metabolismo , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/patologia , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/patologia , Feminino , Humanos , Masculino , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/patologia , Ultrassonografia Doppler Dupla
3.
Georgian Med News ; (273): 11-15, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29328023

RESUMO

To date in patients with subclavian steal syndrome diagnosis is only grade of stenosis or localization of occlusion described. Authors recommend to take into account also type of a collateral compensation of cerebral circulation for selection of an optimal treatment The objective of the research was to study the features of formation of collateral circulation in patients with subclavian steal syndrome. The authors described changes in the direction of blood flow in the extracranial vessels of 42 patients with subclavian steal syndrome. Latent subclavian steal syndrome was detected in 26.2% of patients, transient subclavian steal syndrome was found in 54.8% of patients, and a persistent course of the disease was observed in 19.9% of patients. Symptoms of vertebrobasilar insufficiency were detected in 26.6% of patients, and combination of chronic upper extremity ischemia and vertebrobasilar insufficiency was diagnosed in 73.8% of patients. When analyzing the features of collateral circulation in 64.3% of patients the extracranial compensatory mechanism was observed being provided by three main groups of collateral hemodynamic reallocation: the occipito-vertebral hemodynamic mechanism of compensation was detected in 38.1% of cases, the thyroid compensatory mechanism was found in 16.7% of cases, and the brain stem-occipital compensatory mechanism was observed in 9.5% of cases. In 35.7% of patients the intracranial compensatory mechanism was observed being provided by two main groups of collateral hemodynamic reallocation: the vertebro-vertebral compensatory mechanism was found in 21.4% of cases and cerebrobasilar compensatory mechanism was detected in 14.3% of cases. Consideration of the features of collateral circulation in patients with subclavian steal syndrome may serve as a prognostic criterion for selecting an optimal treatment tactics.Each of compensatory mechanisms has its own hemodynamic peculiarities. The occipito- vertebral compensatory mechanism has the most positive influence on the compensationof hemodynamic failure of the vertebrobasilar basin.


Assuntos
Circulação Colateral/fisiologia , Síndrome do Roubo Subclávio/fisiopatologia , Hemodinâmica , Humanos
4.
Anal Chem ; 84(14): 5869-75, 2012 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-22816778

RESUMO

Second order nonlinear optical imaging of chiral crystals (SONICC) and two-photon excited fluorescence measurements [both autofluorescence and two-photon excited UV-fluorescence (TPE-UVF)] were assessed for the selective detection of APIs relative to common pharmaceutical excipients. Active pharmaceutical ingredients (APIs) compose only a small percentage of most tabulated formulations, yet the API distribution within the tablet can affect drug release and tablet stability. Complementary measurements using either UV-SONICC (266 nm detection) or TPE-UVF were shown to generate signals >50-fold more intense for a model API (griseofulvin) than those produced by common pharmaceutical excipients. The combined product of the measurements produced signals >10(4)-fold greater than the excipients studied. UV-SONICC or TPE-UVF produced greater selectivity than analogous measurements with visible-light detection, attributed to the presence of aromatic moieties within the API exhibiting strong one and two photon absorption at ~266 nm. Complementary SONICC and fluorescence measurements allowed for the sensitive detection of the three-dimensional distribution of tadalafil within a Cialis tablet to a depth of >140 µm.


Assuntos
Excipientes/química , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Fenômenos Ópticos , Preparações Farmacêuticas/química , Raios Ultravioleta , Carbolinas/química , Griseofulvina/química , Pós , Estereoisomerismo , Comprimidos , Tadalafila
5.
Phys Rev Lett ; 109(12): 127203, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-23005980

RESUMO

In this Letter, we explore the phase diagram and excitations of a distorted triangular lattice antiferromagnet. The unique two-dimensional distortion considered here is very different from the "isosceles"-type distortion that has been extensively investigated. We show that it is able to stabilize a 120° spin structure for a large range of exchange interaction values, while new structures are found for extreme distortions. A physical realization of this model is α-CaCr(2)O(4), which has a 120° structure but lies very close to the phase boundary. This is verified by inelastic neutron scattering which reveals unusual rotonlike minima at reciprocal space points different from those corresponding to the magnetic order.

6.
Bratisl Lek Listy ; 112(5): 244-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21682076

RESUMO

OBJECTIVE: Localization of monoamine oxidases (MAO) in rat female gonads during preimplantation period of pregnancy was determined. MATERIAL AND METHODS: Pregnant females were killed on their first, third, and fifth days of pregnancy and animals were transcardially perfused with PBS and fixative solutions. Ovaries, oviducts and uteri were immediately removed and they served for the determination of MAO localization employing the method of enzymatic histochemistry. RESULTS: MAO-A activity in ovary was visible in corpora lutea and in interstitial gland cells while MAO-B was detected predominantly in blood vessels. Both MAO enzymes were seen in the smooth muscle fibers of the ovarian hilum. The presence of MAO enzymes was however not detected in follicles at any stage of their development. In oviduct and uterus, both MAO enzymes were visible in similar places, namely in smooth muscle fibers, mast cells and blood vessels, with no MAO presence seen in the epithelium. CONCLUSIONS: Potential physiological importance of MAO localization in different cells of female reproductive organs during early period of pregnancy is proposed (Fig. 6, Ref. 29).


Assuntos
Blastocisto , Genitália Feminina/enzimologia , Monoaminoxidase/metabolismo , Animais , Tubas Uterinas/enzimologia , Feminino , Ovário/enzimologia , Gravidez , Ratos , Ratos Wistar , Útero/enzimologia
7.
Science ; 166(3905): 619-20, 1969 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-4390429

RESUMO

Hydranths of the colonial marine hydroid Campanularia flexuosa (phylum Cnidaria, class Hydrozoa, order Calyptoblastea) have a mean life span of approximately 7 days in intact colonies in culture. Hydranths then regress and are absorbed, and their cellular materials are utilized by the colony for continued growth. Hydranth life spans can be extended to 20 days in isolated hydranths if, repeatedly, the pedicel is damaged by pinching and is allowed to partially regen-erate. This suggests that tissue damage and reorganization function to maintain the hydranth.


Assuntos
Envelhecimento , Regeneração , Cnidários
8.
J Clin Invest ; 105(5): 673-81, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10712439

RESUMO

Mucolipidosis IIIC, or variant pseudo-Hurler polydystrophy, is an autosomal recessive disease of lysosomal hydrolase trafficking. Unlike the related diseases, mucolipidosis II and IIIA, the enzyme affected in mucolipidosis IIIC (N-Acetylglucosamine-1-phosphotransferase [GlcNAc-phosphotransferase]) retains full transferase activity on synthetic substrates but lacks activity on lysosomal hydrolases. Bovine GlcNAc-phosphotransferase has recently been isolated as a multisubunit enzyme with the subunit structure alpha(2)beta(2)gamma(2). We cloned the cDNA for the human gamma-subunit and localized its gene to chromosome 16p. We also showed, in a large multiplex Druze family that exhibits this disorder, that MLIIIC also maps to this chromosomal region. Sequence analysis of the gamma-subunit cDNA in patients from 3 families identified a frameshift mutation, in codon 167 of the gamma subunit, that segregated with the disease, indicating MLIIIC results from mutations in the phosphotransferase gamma-subunit gene. This is to our knowledge the first description of the molecular basis for a human mucolipidosis and suggests that the gamma subunit functions in lysosomal hydrolase recognition.


Assuntos
Lisossomos/metabolismo , Mucolipidoses/genética , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Sequência de Aminoácidos , Sequência de Bases , Cromossomos Humanos Par 16 , Clonagem Molecular , Feminino , Fibroblastos , Mutação da Fase de Leitura , Ligação Genética , Humanos , Escore Lod , Lisossomos/enzimologia , Masculino , Dados de Sequência Molecular , Mucolipidoses/etiologia , Linhagem , RNA Mensageiro/metabolismo , Análise de Sequência , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo
9.
Mol Cell Biol ; 6(11): 3873-83, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3467176

RESUMO

We assembled three hybrid beta-globin genes by fusing the mouse beta-major promoter and initial transcribed region to one of three goat beta-like globin gene bodies: beta c (preadult), beta F (fetal), or epsilon II (embryonic). Thymidine kinase (tk)-deficient murine erythroleukemia (MEL) cells were cotransformed with one of these constructs and a separate plasmid bearing the tk gene. Half of the 24 cell lines containing either the mouse beta/goat beta c or mouse beta/goat beta F genes expressed the transferred genes at significant levels; in many cases the hybrid genes were, like the endogenous beta-globin genes, inducible with dimethyl sulfoxide. We obtained 13 cell lines containing the mouse beta/goat epsilon II hybrid gene, 6 of which were cotransfected with a mouse beta/human beta fusion gene known to function in MEL cells. In contrast to the results with the other fusion genes, the mouse beta/goat epsilon II hybrid was very poorly expressed: in two separate experiments, 0 of 13 and 2 of 13 lines showed significant mouse beta/goat epsilon II RNA levels after induction. In all these lines the endogenous mouse beta and cotransfected mouse beta/human beta genes were expressed. As an initial test of possible reasons for the inactivity of the mouse beta/goat epsilon II hybrid, we recloned this fusion gene into a tk-bearing plasmid, adjacent to the tk gene. Of 12 cell lines transformed with this plasmid, 11 produced mouse beta/goat epsilon II RNA; in 6 cases the expression was both strong and dimethyl sulfoxide inducible.


Assuntos
Genes , Globinas/genética , Animais , Linhagem Celular , Cabras , Leucemia Eritroblástica Aguda/enzimologia , Leucemia Experimental/metabolismo , Camundongos , Plasmídeos , Regiões Promotoras Genéticas , Timidina Quinase/deficiência , Timidina Quinase/genética , Técnicas do Sistema de Duplo-Híbrido
10.
Bratisl Lek Listy ; 108(8): 364-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18203542

RESUMO

Actinomycosis is an infrequent chronic progressive granulomatous and suppurative disease caused by Actinomyces israelii, a natural inhabitant of the gastrointestinal tract. We report a rare case of a 68-year-old man with primary endobronchial actinomycosis who presented in the emergency respiratory ward with massive hemoptysis and dyspnea. An urgent fiberoptic bronchoscopy revealed hypertrophic mucosa and a narrowed lingular bronchus with a pale extruding exophyt. Diffuse bleeding from the mucosa adjacent to the exophyt was present. Histopathologic evaluation revealed chronic inflammation with abscess formation and clusters of Actinomyces colonies. Therapy with clindamycin maintained for 7 weeks prevented recurrence of the disease. In the light of our case and the review of literature we conclude that early recognition of primary endobronchial actinomycosis associated with hemoptysis and proper antibiotic treatment are essential to prevent undesirable complications including unwarranted surgery (Fig. 2, Ref. 30). Full Text (Free, PDF) www.bmj.sk.


Assuntos
Actinomicose/diagnóstico , Broncopatias/diagnóstico , Hemoptise/etiologia , Actinomicose/complicações , Idoso , Broncopatias/complicações , Humanos , Masculino
11.
Respir Med ; 100(3): 385-92, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16105731

RESUMO

BACKGROUND: Several observational studies suggest that therapy with inhaled corticosteroids (ICS) is associated with reduced mortality in patients with chronic obstructive pulmonary disease (COPD). However, none of these has reported survival data in COPD patients with respiratory insufficiency who require domiciliary oxygen therapy. The present study was conducted to examine the association between ICS and all-cause mortality in patients with severe COPD and chronic hypoxemia. PATIENTS AND METHODS: From a tertiary referral clinic, we identified 145 consecutive COPD patients who met the criteria for long-term oxygen therapy between 1996 and 2002. We compared the hazard ratio (HR) for all-cause mortality over 1 year between patients who were (n=55) and were not treated with ICS (n=90). RESULTS: In a crude analysis, the use of ICS was associated with a HR of 0.38 (95% confidence interval (CI)=0.18-0.79). After adjustments for age, sex, use of oral steroids, and beta2-agonists, PaO2 and PaCO2, the HR was 0.46 (95% CI=0.21-0.98). CONCLUSIONS: Our findings indicate that ICS may reduce all-cause mortality in patients with severe COPD and chronic hypoxemia, who require long-term domiciliary oxygen therapy. These data suggest that ICS may play an important role in improving clinical outcomes in patients with advanced COPD.


Assuntos
Corticosteroides/uso terapêutico , Hipóxia/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Administração por Inalação , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Doença Crônica , Estudos de Coortes , Feminino , Seguimentos , Volume Expiratório Forçado , Humanos , Hipóxia/mortalidade , Masculino , Pessoa de Meia-Idade , Oxigenoterapia/métodos , Modelos de Riscos Proporcionais , Doença Pulmonar Obstrutiva Crônica/mortalidade
12.
Cancer Res ; 41(11 Pt 1): 4727-36, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6272982

RESUMO

The aim of this study was to correlate morphological changes in cells to known phases of the cell cycle. For this purpose, feline lymphoblastoid cells (FL74) chronically infected with feline leukemia virus were synchronized and examined by scanning and transmission electron microscopy. Scanning electron microscopy revealed that the cell surface underwent distinct changes which were found to be cell cycle specific. Morphological changes shown by transmission electron microscopy were used as ultrastructural markers to confirm the findings made by scanning electron microscopy relating to the various phases of the cell cycle. The results of these experiments suggest that the presence of morphologically mixed populations of cells in many lymphoproliferative disorders, which had been described previously, may be explained by normal cell cycle-dependent variations.


Assuntos
Leucemia Experimental/ultraestrutura , Linfócitos/ultraestrutura , Animais , Gatos , Divisão Celular , Linhagem Celular , Interfase , Vírus da Leucemia Felina , Microscopia Eletrônica de Varredura , Mitose , Infecções Tumorais por Vírus
13.
Exp Clin Endocrinol Diabetes ; 124(10): 588-592, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27437916

RESUMO

Neutrophil granulocytes form the biggest free radical producing system of the human body. The importance of this system in atherosclerotic plaque formation and other free radical mediated disorders is confirmed by both in vivo and in vitro studies. Estrogen's effect on free radical production involves multiple estrogen receptors and occurs both on transcriptional and on protein phosphorylational level. Estrogen decreases the superoxide production of neutrophil granulocytes in such a short time frame it is unlikely to be mediated by transcription regulation. We investigated the underlying mechanism through which the mentioned estrogen effect takes place using an immunabsorption-based method. Phosphorylation data of 43 different messenger proteins were used for pathway analysis. The newly identified pathway involved largely second messengers from previously described non-genomic estrogen effects and affected superoxide production via Rac1 - an important regulator of free radical production and chemotaxis. Selective inhibition of the participating second messengers altered superoxide production in the predicted direction confirming that this pathway is at least partly responsible for the effect of 17-ß-estradiol on chemoattractant induced superoxide production.


Assuntos
Estradiol/metabolismo , Neutrófilos/metabolismo , Superóxidos/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Adulto , Feminino , Humanos , Masculino , Redes e Vias Metabólicas , Pessoa de Meia-Idade
14.
J Phys Condens Matter ; 27(16): 166002, 2015 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-25817594

RESUMO

Linear spin wave theory provides the leading term in the calculation of the excitation spectra of long-range ordered magnetic systems as a function of 1/√S. This term is acquired using the Holstein-Primakoff approximation of the spin operator and valid for small δS fluctuations of the ordered moment. We propose an algorithm that allows magnetic ground states with general moment directions and single-Q incommensurate ordering wave vector using a local coordinate transformation for every spin and a rotating coordinate transformation for the incommensurability. Finally we show, how our model can determine the spin wave spectrum of the magnetic C-site langasites with incommensurate order.

15.
Transplant Proc ; 47(6): 1600-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26293020

RESUMO

The low availability of donor organs requires long-term successful transplantation as an accepted therapy for patients with end-stage renal and liver diseases. The health benefits of regular physical activity are well known among healthy individuals as well as patients under rehabilitation programs. Our aim was to describe the cardiorespiratory capacity of the Hungarian National Transplant Team. Twenty-five kidney (n = 21) or liver (n = 4) transplant athletes participated in this study. Maximal cardiorespiratory capacity (VO2max) was measured on a treadmill with the use of gas analysis. After a resting pulmonary function test, subjects completed a vita maxima test until exhaustion. Aerobic capacity of transplant athletes was higher than the age- and sex-predicted cardiorespiratory fitness (VO2max, 109.9 ± 21.7% of the predicted values; P = .0101). Resting respiratory function indicators exceeded 80% of predicted age- and sex-matched normal values. There were positive correlations between VO2max and workload (r(2) = 0.40; P = .0463), metabolic equivalent (r(2) = 0.72; P < .0001), and oxygen pulse (r(2) = 0.30; P = .0039). However, age showed negative correlation with VO2max (r(2) = 0.32; P = .0031), and there was no significant correlation between graft age and maximal oxygen consumption (r(2) = 0.15; P = .4561). Although the small amount of participants can not represent the general kidney and liver transplant population, the excellent cardiorespiratory performance suggests that a normal level of physical capacity is available after transplantation and can be even higher with regular physical activity. This favorable physiologic background leads to a state that provides proper graft oxygenization, which is an important factor in long-term graft survival.


Assuntos
Tolerância ao Exercício/fisiologia , Transplante de Rim , Transplante de Fígado , Aptidão Física/fisiologia , Adulto , Atletas , Pressão Sanguínea/fisiologia , Teste de Esforço , Feminino , Rejeição de Enxerto/prevenção & controle , Frequência Cardíaca , Humanos , Hungria , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Testes de Função Respiratória , Estudos Retrospectivos
16.
Gene ; 243(1-2): 161-6, 2000 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-10675624

RESUMO

The exon-intron organization and sequences of the exon-intron boundaries of the human gp130 transmembrane receptor gene have been determined using genomic DNAs as samples. The gp130 gene comprises 17 exons and 16 introns. The positions of the exon-intron boundaries show good correlation to the functional/homology regions of gp130. Exons 3-17 code for the gp130 protein, and each subdomain of the receptor is encoded by a set of exons. The coding potential of exons and the intron phasing of the human gp130 gene conform to the patterns observed previously for other cytokine receptor genes. This supports the notions that the gp130 gene evolved from the same ancestral gene that gave rise to other members of the cytokine receptor family.


Assuntos
Antígenos CD/genética , Éxons , Íntrons , Glicoproteínas de Membrana/genética , Sequência de Bases , Receptor gp130 de Citocina , DNA/química , DNA/genética , Genes/genética , Humanos , Dados de Sequência Molecular , Análise de Sequência de DNA
17.
Gene ; 194(1): 19-24, 1997 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-9266668

RESUMO

We previously cloned a B. bronchiseptica (Bb) genomic DNA fragment that complements a Bb alcaligin biosynthesis mutant, and reported the identification of a gene, alcA, with predicted protein sequence similarity to siderophore biosynthesis enzymes from other organisms. In the present study we show that further nt sequencing of this region revealed two open reading frames (ORFs) 3' to alcA that encode putative proteins AlcB and AlcC, with significant sequence similarity to the aerobactin biosynthesis enzymes IucB and IucC, respectively. RT-PCR analysis indicated that the three ORFs are encoded on a single transcript, and that this operon is repressed at the transcriptional level by Fe. Primer extension analysis placed the transcriptional start point (tsp) 35 nt from the 5' end of the Fur consensus sequence and 188 nt from the putative start of translation of AlcA.


Assuntos
Proteínas de Bactérias/genética , Bordetella bronchiseptica/genética , Ácidos Hidroxâmicos , Óperon , Sideróforos/biossíntese , Sequência de Aminoácidos , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/química , Sequência de Bases , Bordetella bronchiseptica/enzimologia , Sequência Consenso , Primers do DNA , Teste de Complementação Genética , Dados de Sequência Molecular , Mutagênese , Fases de Leitura Aberta , Reação em Cadeia da Polimerase , Biossíntese de Proteínas , Homologia de Sequência de Aminoácidos , Transcrição Gênica
18.
Gene ; 167(1-2): 133-6, 1995 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-8566764

RESUMO

The alcA gene, essential for the production of the dihydroxamate siderophore, alcaligin, by Bordetella bronchiseptica, was cloned and sequenced. The alcA gene was identified on a 4.7-kb EcoRI genomic fragment adjacent to a Tn5lac transposon insertion that inactivated alcaligin production in strain MBORD846. Analysis of the alcA nucleotide sequence revealed a putative Fur-binding site, suggesting that expression of this gene is repressed by iron. The deduced amino-acid sequence of this open reading frame had significant homology with the Escherichia coli iucD gene product, an enzyme required for biosynthesis of the dihydroxamate siderophore aerobactin.


Assuntos
Bordetella bronchiseptica/genética , Ácidos Hidroxâmicos , Sideróforos/biossíntese , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Ferro/fisiologia , Dados de Sequência Molecular , RNA Mensageiro/genética , Homologia de Sequência de Aminoácidos
19.
Gene ; 179(2): 199-204, 1996 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-8972900

RESUMO

In a search for clones from a lambda gt11 expression library of Actinobacillus actinomycetemcomitans (Aa) genomic DNA that expressed epitopes from a 70-kDa iron-repressible membrane protein, we inadvertently identified clones that encoded a member of the 90-kDa heat-shock protein (HSP 90) family. The gene appears to encode a homologue of HtpG, as the nucleotide sequence has approximately 70% identity with the Escherichia coli (Ec) and Vibrio fischeri htpG. Growth of an Aa htpG insertion mutant at 42 degrees C was reduced to 50% of the parent strain, similar to an Ec htpG deletion mutant. These data suggest that Aa HtpG performs a function similar to Ec HtpG.


Assuntos
Aggregatibacter actinomycetemcomitans/genética , Proteínas de Bactérias/genética , Proteínas de Escherichia coli , Proteínas de Choque Térmico HSP90/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Bacteriano , Dados de Sequência Molecular , Mutagênese Insercional , Fenótipo , Mapeamento por Restrição , Deleção de Sequência , Homologia de Sequência de Aminoácidos
20.
Clin Exp Metastasis ; 17(10): 809-16, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-11089878

RESUMO

Autocrine motility factor (AMF) is one of the motility cytokines regulating tumor cell migration, therefore identification of the signaling pathway coupled with it has critical importance. Previous studies revealed several elements of this pathway predominated by lipoxygenase-PKC activations but the role for tyrosine kinases remained questionable. Motility cytokines frequently have mitogenic effect as well, producing activation of overlapping signaling pathways therefore we have used B16a melanoma cells as models where AMF has exclusive motility effect. Our studies revealed that in B16a cells AMF initiated rapid (1-5 min) activation of the protein tyrosine kinase (PTK) cascade inducing phosphorylation of 179, 125, 95 and 40/37 kD proteins which was mediated by upstream cyclo- and lipoxygenases. The phosphorylated proteins were localized to the cortical actin-stress fiber attachment zones in situ by confocal microscopy. On the other hand, AMF receptor activation induced significant decrease in overall serine-phosphorylation level of cellular proteins accompanied by serine phosphorylation of 200, 90, 78 and 65 kd proteins. The decrease in serine phosphorylation was independent of PTKs, PKC as well as cyclo- and lipoxygenases. However, AMF induced robust translocation of PKCalpha to the stress fibers and cortical actin suggesting a critical role for this kinase in the generation of the motility signal. Based on the significant decrease in serine phosphorylation after AMF stimulus in B16a cells we postulated the involvement of putative serine/threonine phosphatase(s) upstream lipoxygenase and activation of the protein tyrosine kinase cascade downstream cyclo- and lipoxygenase(s) in the previously identified autocrine motility signal.


Assuntos
Movimento Celular/fisiologia , Glucose-6-Fosfato Isomerase/fisiologia , Lipoxigenase/metabolismo , Melanoma/metabolismo , Serina/metabolismo , Tirosina/metabolismo , Actinas/ultraestrutura , Animais , Inibidores Enzimáticos/farmacologia , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Lipoxigenase/efeitos dos fármacos , Inibidores de Lipoxigenase/farmacologia , Melanoma/patologia , Camundongos , Microscopia Confocal , Fosforilação , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Proteína Quinase C-alfa , Proteínas/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
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