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1.
Pneumologie ; 75(9): 644-650, 2021 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-33882609

RESUMO

Despite growing experience due to increasing patient numbers, the intensive care treatment of patients with severe COVID-19 pneumonia continues to be a particular challenge in individual cases, which may also therefore legitimize individualized therapeutic attempts. In this context, the so-called hyperinflammation syndrome characterized by a cytokine storm accompanied by a massive increase in inflammatory markers such as interleukin(IL)-6, represents such a situation. This case report describes the therapeutic approach of using the IL-6-specific antibody tocilizumab in combination with hemoadsorption therapy (CytoSorb) in a 58-year-old male patient with severe COVID-19 pneumonia. The patient suffered a massive clinical deterioration with concomitant Horovitz index of 127 mmHg that occurred on the 6th day of ventilation. After combined application of the above-mentioned therapeutic approaches, the patient stabilized rapidly paralleled by a significant increase in the Horovitz index, and the possibility of de-escalating the ventilation regimen, which ultimately enabled successful extubation after only 13 days of ventilation. Moreover, the combined treatment was associated with significant hemodynamic stabilization and a consecutive reduction in vasopressor doses, while hyperinflammation could be kept well under control. The incorporation of the hemoadsorber into the therapeutic regimen proved to be safe and straightforward. In conclusion, the combination of CytoSorb therapy and IL-6 blockade by tocilizumab appeared, at least in this case, to be an effective measure to modulate an overshooting immune response in COVID-19 pneumonia with a concomitant clinical improvement in both respiratory and hemodynamic function, and thus could be used as a potential therapeutic option in this clinical picture.


Assuntos
Tratamento Farmacológico da COVID-19 , Síndrome da Liberação de Citocina , Anticorpos Monoclonais Humanizados , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Resultado do Tratamento
2.
J Exp Med ; 185(12): 2171-6, 1997 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-9182688

RESUMO

A novel human CC chemokine consisting of 78 amino acids and having a molecular mass of 8,778.3 daltons (VVIPSPCCMF FVSKRIPENR VVSYQLSSRS TCLKAGVIFT TKKGQQ SCGD PKQEWVQRYM KNLDAKQKKA SPRARAVA) was isolated together with three minor COOH-terminally truncated variants with 73, 75, and 76 residues. The new chemokine was termed eotaxin-2 because it is functionally very similar to eotaxin. In terms of structure, however, eotaxin and eotaxin-2 are rather distant, they share only 39% identical amino acids and differ almost completely in the NH2-terminal region. Eotaxin-2 induced chemotaxis of eosinophils as well as basophils, with a typically bimodal concentration dependence, and the release of histamine and leukotriene C4 from basophils that had been primed with IL-3. In all assays, eotaxin-2 had the same efficacy as eotaxin, but was somewhat less potent. The migration and the release responses were abrogated in the presence of a monoclonal antibody that selectively blocks the eotaxin receptor, CCR3, indicating that eotaxin-2, like eotaxin, acts exclusively via CCR3. Receptor usage was also studied in desensitization experiments by measuring [Ca2+]i changes in eosinophils. Complete cross-desensitization was observed between eotaxin-2, eotaxin and MCP-4 confirming activation via CCR3. No Ca2+ mobilization was obtained in neutrophils, monocytes and lymphocytes, in agreement with the lack of chemotactic responsiveness. Intradermal injection of eotaxin-2 in a rhesus monkey (100 or 1,000 pmol per site) induced a marked local infiltration of eosinophils, which was most pronounced in the vicinity of postcapillary venules and was comparable to the effect of eotaxin.


Assuntos
Basófilos/efeitos dos fármacos , Quimiocinas CC , Fatores Quimiotáticos de Eosinófilos/farmacologia , Citocinas/farmacologia , Eosinófilos/efeitos dos fármacos , Receptores de Quimiocinas , Receptores de Citocinas/fisiologia , Sequência de Aminoácidos , Animais , Quimiocina CCL11 , Quimiotaxia , Citocinas/química , Liberação de Histamina/efeitos dos fármacos , Humanos , Leucotrieno C4/metabolismo , Macaca mulatta , Masculino , Dados de Sequência Molecular , Receptores CCR3
3.
J Exp Med ; 189(5): 821-9, 1999 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10049946

RESUMO

The initiation of an immune response is critically dependent on the activation of dendritic cells (DCs). This process is triggered by surface receptors specific for inflammatory cytokines or for conserved patterns characteristic of infectious agents. Here we show that human DCs are activated by influenza virus infection and by double-stranded (ds)RNA. This activation results not only in increased antigen presentation and T cell stimulatory capacity, but also in resistance to the cytopathic effect of the virus, mediated by the production of type I interferon, and upregulation of MxA. Because dsRNA stimulates both maturation and resistance, DCs can serve as altruistic antigen-presenting cells capable of sustaining viral antigen production while acquiring the capacity to trigger naive T cells and drive polarized T helper cell type 1 responses.


Assuntos
Células Dendríticas/imunologia , Proteínas de Ligação ao GTP , Orthomyxoviridae/imunologia , RNA de Cadeia Dupla/imunologia , Apresentação de Antígeno , Antivirais/biossíntese , Comunicação Autócrina , Efeito Citopatogênico Viral , Células Dendríticas/virologia , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Interferon-alfa/biossíntese , Ativação Linfocitária , Complexo Principal de Histocompatibilidade/imunologia , Proteínas de Resistência a Myxovirus , Peptídeos/imunologia , Biossíntese de Proteínas , Linfócitos T/imunologia , Células Th1/imunologia
4.
Science ; 270(5237): 792-4, 1995 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-7481766

RESUMO

A heptadecapeptide was identified and purified from porcine brain tissue as a ligand for an orphan heterotrimeric GTP-binding protein (G protein)-coupled receptor (LC132) that is similar in sequence to opioid receptors. This peptide, orphanin FQ, has a primary structure reminiscent of that of opioid peptides. Nanomolar concentrations of orphanin FQ inhibited forskolin-stimulated adenylyl cyclase activity in cells transfected with LC132. This inhibitory activity was not affected by the addition of opioid ligands, nor did the peptide activate opioid receptors. Orphanin FQ bound to its receptor in a saturable manner and with high affinity. When injected intracerebroventricularly into mice, orphanin FQ caused a decrease in locomotor activity but did not induce analgesia in the hot-plate test. However, the peptide produced hyperalgesia in the tail-flick assay. Thus, orphanin FQ may act as a transmitter in the brain by modulating nociceptive and locomotor behavior.


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Peptídeos Opioides/isolamento & purificação , Peptídeos Opioides/metabolismo , Receptores de Neuropeptídeos/metabolismo , Receptores Opioides/metabolismo , Inibidores de Adenilil Ciclases , Sequência de Aminoácidos , Analgésicos/farmacologia , Animais , Células CHO , Colforsina/farmacologia , Cricetinae , Hipotálamo/química , Injeções Intraventriculares , Injeções Espinhais , Ligantes , Camundongos , Dados de Sequência Molecular , Atividade Motora/efeitos dos fármacos , Peptídeos Opioides/química , Peptídeos Opioides/farmacologia , Medição da Dor , Suínos , Transfecção , Nociceptina
5.
Unfallchirurg ; 112(3): 349-52, 2009 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-19240993

RESUMO

BACKGROUND: Five years after implementation of a medical documentation assistant (MDA) as a pilot project in our trauma department, this paper examines the results. METHODS: We evaluate practice and integration in our daily ward/department work. The measurable parameter or "value" of the MDA is the settlement reserve demonstrated as the cost weight (CW) for better demonstration of performance. RESULTS: The MDA is now an essential part of the daily routine in our department. In addition to the advisory function in codifying medical services, relevant secondary diagnoses are documented and clinical progress is checked to identify additional profitable services. We thus achieve an average additional monthly CW benefit of 11.4046. We have not yet assessed the improved documentation of medical records, which is especially important when checked by the medical service of the health fund. Furthermore, half of the hours of one doctor can thus be saved and therefore used for proper medical activities every day.


Assuntos
Documentação , Eficiência Organizacional , Sistemas Computadorizados de Registros Médicos , Assistentes Médicos , Traumatologia/organização & administração , Alemanha , Recursos Humanos
6.
Vet Rec ; 163(15): 441-4, 2008 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-18849575

RESUMO

A cross-sectional study was carried out in spring 2007, at the end of the first bluetongue outbreak season, to determine the geographical spread of bluetongue virus serotype 8 (btv-8) infection in cattle in the Netherlands and the consequences for some production parameters. Blood samples from cattle submitted to the laboratory of the Dutch Animal Health Service for other voluntary and obligatory health programmes were tested serologically for btv-8. In total, 37,073 samples were tested and 659 (1.78 per cent) were seropositive. The samples came from 5436 herds, of which 45 per cent of herds had only one sample submitted from them. The prevalence was highest in the south of the country, where the outbreak had started, and decreased towards the north. In 340 herds more than 50 per cent of cattle were tested, of which 156 herds were located in infected compartments, and in 37 of these herds (10.9 per cent) at least one positive cow was detected. The average within-herd prevalence in the 37 herds was 39.3 per cent: 2.2 per cent in 11 dairy herds, 68.4 per cent in 20 small-scale herds and 14 per cent in four suckler cow herds. The prevalence differed significantly between herd types but did not show a geographical trend. The average net return for milk production amounted to euro2417/cow/year and it decreased significantly on average by euro48/cow/year in the bluetongue-infected dairy herds during the bluetongue period. On the small-scale farms, the incidence of mortality increased by 3.2 (95 per cent confidence interval [CI] 1.2 to 9.1) times in the infected herds during the bluetongue period, but the voluntary culling rate decreased by a factor of 2.3 (95 per cent CI 1.1 to 4.8).


Assuntos
Anticorpos Antivirais/sangue , Vírus Bluetongue/imunologia , Bluetongue/epidemiologia , Doenças dos Bovinos/epidemiologia , Animais , Bluetongue/sangue , Vírus Bluetongue/classificação , Vírus Bluetongue/isolamento & purificação , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/virologia , Estudos Transversais , Surtos de Doenças/veterinária , Ensaio de Imunoadsorção Enzimática , Modelos Lineares , Leite/economia , Países Baixos/epidemiologia , Estudos Soroepidemiológicos
7.
Lung Cancer ; 55(2): 165-71, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17129635

RESUMO

PURPOSE: The relevance of (18)F-FDG PET for staging non-small cell lung cancer (NSCLC), in particular for the detection of lymph node or distant metastases, has been shown in several studies. The value of FDG-PET for therapy monitoring in NSCLC, in contrast, has not yet been sufficiently analysed. Aim of this study was to evaluate FDG-PET for monitoring treatment response during and after neoadjuvant radiochemotherapy (NARCT) in advanced NSCLC. METHODS: Sixty-five patients with histologically proven NSCLC stage III initially underwent three FDG-PET investigations, during NARCT prior to initiating radiation, and post-NARCT. Changes of FDG-uptake in the primary tumour at two time-points during NARCT were analysed concerning their impact on long-term survival. RESULTS: The mean maximum FDG uptake (standardized uptake value, SUVmax) of the whole group decreased significantly during NARCT (SUVmax PET 1: 14.9+/-4.0, SUVmax PET 3: 5.5+/-2.4, p=0.004). The difference between initial FDG uptake (PET 1) and uptake after induction chemotherapy (PET 2) was found to be highly predictive for long-term survival patients which had a greater than 60% decreases in their SUV change had a significantly longer survival than those below this threshold (5-year-survival 60% versus 15%, p=0.0007). Patients who had a lower than 25% decrease in their SUV change had a 5-years-survival lower than 5%. Furthermore, the difference between initial FDG uptake (PET 1) and uptake after completion of the whole NARCT (PET 3) was predictive for survival when 75% was applied as cut-off (p=0.02). However, the level of significance was considerably lower. CONCLUSION: FDG-PET is suitable for therapy monitoring in patients with stage III NSCLC. The decrease of FDG uptake during induction chemotherapy is highly predictive for patient outcome.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Fluordesoxiglucose F18/farmacocinética , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Compostos Radiofarmacêuticos/farmacocinética , Adulto , Idoso , Área Sob a Curva , Carboplatina/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Paclitaxel/uso terapêutico , Cintilografia , Análise de Sobrevida
8.
Nat Biotechnol ; 18(1): 66-70, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10625394

RESUMO

We describe an assay system for the identification of site-specific proteases. The assay is based on a protein substrate that is immobilized on ceramic beads. After incubation with cell homogenates, the beads are washed and digested with endoproteinase Lys-C to liberate a defined set of peptides. The peptide fragments are identified by mass spectrometry. The assay was used to screen for beta-secretase, the protease that cleaves amyloid precursor protein (APP) at the beta-site. Cathepsin D was identified as the enzyme responsible for beta-secretase-like activity in two cell lines. Subsequent analysis of the related aspartic protease, cathepsin E, revealed almost identical cleavage specificity. Both enzymes are efficient in cleaving Swedish mutant APP at the beta-site but show almost no reactivity with wild-type APP. Treatment of cell lines with pepstatin inhibited the production of amyloid peptide (Abeta) when they were transfected with a construct bearing the Swedish APP mutant. However, when the cells were transfected with wild-type APP, the generation of Abeta was increased. This suggests that more than one enzyme is capable of generating Abeta in vivo and that an aspartic protease is involved in the processing of Swedish mutant APP.


Assuntos
Ácido Aspártico Endopeptidases/metabolismo , Catepsina D/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Sequência de Aminoácidos , Secretases da Proteína Precursora do Amiloide , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Ácido Aspártico Endopeptidases/química , Catepsina D/química , Catepsina E/genética , Catepsina E/metabolismo , Extratos Celulares/química , Linhagem Celular , Cerâmica , Endopeptidases , Humanos , Metaloendopeptidases/metabolismo , Camundongos , Microesferas , Dados de Sequência Molecular , Peso Molecular , Mutação/genética , Pepstatinas/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Ratos , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Reprodutibilidade dos Testes , Especificidade por Substrato , Suécia , Transfecção
9.
Biochim Biophys Acta ; 1524(1): 51-6, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11078958

RESUMO

Human napsin A is an aspartic proteinase highly expressed in kidney and lung. To elucidate whether napsin A is excreted in the urine we have performed an immunochemical study using anti-napsin A polyclonal antibody. As a result an immunoreactive band at approx. 38 kDa was detected which corresponds to the molecular mass of recombinant active human napsin A. A deglycosylation study showed that excreted napsin A is N-glycosylated on apparently all of the three potential glycosylation sites. Immunoreactive napsin A was also observed in urine from patients with a transplanted kidney whose kidney function appeared half to fully normal. On the other hand, no or very low immunostaining was detected in samples from patients with diseased kidneys. The urinary excretion pattern correlates well with the enzymatic activity of napsin A. These data show that human napsin A is excreted as functional proteinase in the urine. Furthermore, immunochemical studies suggest a relation between urinary excretion of napsin A and renal function. More specifically, lack of urinary excretion of napsin A could potentially serve as a tool for the detection of kidney dysfunction.


Assuntos
Ácido Aspártico Endopeptidases/análise , Ácido Aspártico Endopeptidases/urina , Nefropatias/urina , Adulto , Idoso , Biomarcadores/urina , Western Blotting , Eletroforese em Gel de Poliacrilamida , Feminino , Glicosídeo Hidrolases , Glicosilação , Humanos , Imunoquímica/métodos , Testes de Função Renal , Transplante de Rim , Masculino , Pessoa de Meia-Idade
10.
J Mol Biol ; 266(1): 23-30, 1997 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-9054967

RESUMO

A single amino acid substitution, Phe98 to Tyr98, in dihydrofolate reductase (DHFR) is the molecular origin of trimethoprim (TMP) resistance in Staphylococcus aureus. This active site amino acid substitution was found in all S. aureus TMP-resistant clinical isolates tested. In order to explore the structural role of Tyr98 in TMP-resistance the ternary complexes of the chromosomal S. aureus DHFR (SaDHFR) with methotrexate (MTX) and TMP in the presence of nicotinamide adenine dinucleotide phosphate (NADPH) as well as that of mutant Phe98Tyr DHFR SaDHFR(F98Y) ternary folate-NADPH complex have been determined by X-ray crystallography. Critical evidence concerning the resistance mechanism has also been provided by NMR spectral analyses of 15N-labelled TMP in the ternary complexes of both wild-type and mutant enzyme. These studies show that the mutation results in loss of a hydrogen bond between the 4-amino group of TMP and the carbonyl oxygen of Leu5. This mechanism of resistance is predominant in both transferable plasmid-encoded and non-transferable chromosomally encoded resistance. Knowledge of the resistance mechanism at a molecular level could help in the design of antibacterials active against multi-resistant Staphylococcus aureus (MRSA), one of todays most serious problems in clinical infectology.


Assuntos
Fenilalanina , Conformação Proteica , Staphylococcus aureus/enzimologia , Tetra-Hidrofolato Desidrogenase/química , Tetra-Hidrofolato Desidrogenase/genética , Resistência a Trimetoprima , Sítios de Ligação , Cromossomos Bacterianos , Cristalografia por Raios X , Humanos , Modelos Moleculares , Conformação Molecular , NADP/química , NADP/metabolismo , Mutação Puntual , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Tetra-Hidrofolato Desidrogenase/metabolismo , Trimetoprima/química , Trimetoprima/metabolismo , Tirosina
11.
Biochimie ; 71(1): 23-32, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2497794

RESUMO

Quantitative analysis of time-resolved anisotropy measurements of DPH or TMA-DPH in lipid vesicles yields more than one mathematically correct solution. The solutions differ with respect to the average orientation and to the reorientational dynamics of the probe molecules in the bilayer. This leads to quite opposite results regarding the effects of cholesterol on membrane fluidity. One solution predicts an increase in fluidity, the other a decrease. Angle-resolved fluorescence depolarization (AFD) measurements of probes in oriented lipid bilayers enable determination of the average orientation of the probes in the bilayer and, if the fluorescence decay function is known, of the reorientational dynamics. Analysis of AFD measurements of DPH and TMA-DPH show that increasing unsaturation leads to a decrease in molecular order and a decrease in reorientational dynamics (= fluidity) of the probes. At temperatures above the phase transition of the lipids, the addition of cholesterol causes an increase in molecular order and an increase in reorientational dynamics (= fluidity). The plant sterol stigmaterol, which is structurally closely related to cholesterol, has different effects than cholesterol. The effects vary with the structure of the surrounding lipids. The membrane fluidity concept as it was originally proposed by Chapman attempts to describe the structural and dynamic properties of lipids in a membrane using one single parameter indicated as 'membrane fluidity'. Our results show that it is necessary to distinguish between structural parameters describing molecular order and motion parameters describing molecular dynamics, thus supporting a similar suggestion by Seelig and Seelig. In order to be useful, the membrane fluidity concept has to be limited to the parameters describing molecular dynamics.


Assuntos
Difenilexatrieno , Bicamadas Lipídicas , Fluidez de Membrana , Polienos , Colesterol , Difenilexatrieno/análogos & derivados , Polarização de Fluorescência , Corantes Fluorescentes , Lipídeos , Membranas Artificiais , Espectrometria de Fluorescência
12.
Atherosclerosis ; 150(2): 397-401, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10856532

RESUMO

BACKGROUND AND PURPOSE: Although it is known that smoking is associated with an increase in arterial wall thickness, most studies have been performed in heterogeneous groups of older age, already suffering from atherosclerotic diseases or having additional cardiovascular risk factors. The purpose of this study is to assess the effect on arterial wall thickness of the carotid and femoral artery in cigarette smokers. METHODS: In a cross-sectional study, intima-media thickness of the common and internal carotid artery, carotid bulb and common femoral artery was determined with the use of a B-mode ultrasound device, in 184 (44.3+/-9.0 years) cigarette smokers for whom smoking is the single cardiovascular risk factor. Comparisons were made with 56 non-smokers, matching in age and gender. RESULTS: The posterior walls of both carotid bulbs (right: P=0.0005; left: P=0.02) and of the internal carotid arteries (right: P=0.004; left: P=0.003) as well as the posterior wall of the right common carotid artery (P=0.02) and of the right common femoral artery (P<0.0001) were thicker in smokers. CONCLUSIONS: Cigarette smoking as the single cardiovascular risk factor causes wall thickening of the carotid and femoral arteries, which indicates that early atherosclerosis is already present in smokers entering middle age.


Assuntos
Arteriosclerose/patologia , Artéria Carótida Primitiva/patologia , Artéria Carótida Interna/patologia , Artéria Femoral/patologia , Fumar/efeitos adversos , Túnica Íntima/patologia , Adulto , Idoso , Arteriosclerose/diagnóstico por imagem , Arteriosclerose/etiologia , Artéria Carótida Primitiva/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Estudos Transversais , Feminino , Artéria Femoral/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Inquéritos e Questionários , Túnica Íntima/diagnóstico por imagem , Ultrassonografia
13.
Thromb Haemost ; 78(2): 799-802, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9268174

RESUMO

A number of studies evaluating deep venous thrombosis (DVT) have demonstrated that plasma levels of thrombotic and fibrinolytic parameters change during treatment, but the relationship between thrombus regression and evolution of these markers remains unknown. The objective of the present study was to correlate levels of D-Dimer (DD) with thrombus regression as assessed by duplex scanning. From 44 patients treated for acute DVT, DD were determined at diagnosis and at the end of initial heparin therapy of at least 5 days. Thrombus regression was measured by repeated duplex scanning at diagnosis and after 1 and 3 months. DD significantly decreased during heparin treatment as compared with values at presentation. DD levels were significantly higher in the group of patients without normalization of the DVT after 3 months (p = 0.003). A ninefold excess tendency was seen for DD levels > 1200 ng/ml at the end of initial treatment to be associated with poor resolution of the DVT [odds ratio 9.0, 0.95 confidence interval (CI) 2.3-35.4]. When the patients with an established malignancy were excluded, the differences were even more significant (p = 0.0004 for DD levels after initial treatment and an odds ratio of 17.5, 0.95 CI 3.3-92.5). These results suggest that increased DD levels after the initial phase of treatment are related to poor resolution of DVT after 3 months. These findings contribute to further insight into the process of thrombus regression. Furthermore high DD levels might help to identify the patients with a poor prognosis and could be useful to judge the efficacy of anticoagulant treatment.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Tromboflebite/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Tromboflebite/fisiopatologia
14.
Am J Cardiol ; 53(4): 590-7, 1984 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-6695789

RESUMO

The influence of heart rate on left ventricular (LV) volumes and ejection fraction (EF) using 2-dimensional (2-D) echocardiography during atrial pacing was analyzed. The study was performed in 13 normal control subjects, 23 patients with coronary heart disease and 8 patients with dilated cardiomyopathy. An electronic sector scanner (2.25 MHz, 84 degrees) was used. Under constant scanning of the left ventricle, heart rate was increased, in steps of 20 beats/min, from 80 to 140 beats/min. The 2-D echocardiograms were stored on videotape and analyzed off-line. The end-diastolic and end-systolic volumes (EDV and ESV) were determined using a disc method. Stroke volume (SV) and EF were calculated. Constant LV scanning was possible during atrial stimulation, as shown by the analysis of simultaneously recorded 2-D echocardiograms and cineventriculograms at different heart rates, revealing a constant position of the echocardiographic transducer. Simultaneous recordings of cineventriculography and 2-D echocardiography at 80 and 120 beats/min showed that despite differences in absolute values, percent changes of LV volumes and EF determined with both methods were similar. Thus, changes of LV function can be analyzed by 2-D echocardiography. In normal control subjects, an increase in heart rate of 10 beats/min reduced EDV by 4 ml, ESV by 2 ml, SV by 2 ml and EF by 1%, corresponding to percent reductions of 4, 2, 5 and -2%, respectively. In contrast, the absolute decreases in the patients were 6 ml, 1 ml, 5 ml and 2% and the percent changes 2%, 1%, 8% and 5%.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Débito Cardíaco , Frequência Cardíaca , Volume Sistólico , Adulto , Idoso , Cateterismo Cardíaco , Estimulação Cardíaca Artificial , Volume Cardíaco , Cardiomiopatia Dilatada/fisiopatologia , Doença das Coronárias/fisiopatologia , Ecocardiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica
15.
Invest Radiol ; 30(7): 421-6, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7591651

RESUMO

RATIONALE AND OBJECTIVES: Conventional intraoral radiography was compared with axial computed tomography (CT) scans for identification and classification of bony pockets in dentate jaw segments. METHODS: Fifty-five artificial bone defects were produced in six dentate jaw segments. The jaws were examined radiographically using a dental x-ray unit and by contiguous axial CT scans. Identification, classification, and vertical depth of the bony defects were compared among the specimens, radiographs, and CT scans. RESULTS: On the intraoral radiographs, 38 (69%) bony lesions were identified, and the vertical depth was underestimated by a mean of 2.2 mm, compared with the objective measurements on the jaws. In contrast, all artificial bony lesions (100%) were identified and classified on the axial CT scans and the vertical depth was underestimated by a mean of 0.5 mm. CONCLUSIONS: High-resolution CT improves the identification and metric assessment of the vertical dimension of infra-alveolar bony lesions compared with conventional intraoral x-ray films and allows these defects to be classified according to the number of existing walls into one-walled, two-walled, and three-walled bony pockets. In patients with apically extended metallic restorations, the image quality could be limited by artifacts.


Assuntos
Perda do Osso Alveolar/diagnóstico por imagem , Processo Alveolar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Perda do Osso Alveolar/patologia , Processo Alveolar/patologia , Cefalometria , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/patologia , Maxila/diagnóstico por imagem , Maxila/patologia , Bolsa Periodontal/diagnóstico por imagem , Bolsa Periodontal/patologia , Probabilidade , Intensificação de Imagem Radiográfica/métodos , Radiografia Dentária , Sensibilidade e Especificidade
16.
Invest Radiol ; 28(8): 686-9, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8376000

RESUMO

OBJECTIVES: The authors assessed the relative efficacy of conventional and digital storage-phosphor radiographs for the detection of skull fractures. METHODS: Fifty conventional film-screen radiographs (FSR) and 50 digital storage-phosphor radiographs (DR) with 66 fractures were compared. Five radiologists evaluated image quality and fracture detectability. The results were analyzed by receiver operating characteristic (ROC) curve analysis. RESULTS: With a standard exposure, the ability to evaluate skull fractures was equally good with either technique (ROC area for DR, 0.8954; for FSR, 0.8870). Digital radiography was superior in evaluating nasal bone. For petrosal bone, the DR image simulates an underexposure. This disadvantage compared with FSR can be compensated by image postprocessing. CONCLUSION: In evaluation of skull fractures, radiologists performance with DR is equivalent to FSR.


Assuntos
Intensificação de Imagem Radiográfica , Fraturas Cranianas/diagnóstico por imagem , Crânio/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Criança , Pré-Escolar , Estudos de Avaliação como Assunto , Humanos , Lactente , Pessoa de Meia-Idade , Variações Dependentes do Observador , Curva ROC , Intensificação de Imagem Radiográfica/instrumentação , Fraturas Cranianas/epidemiologia , Ecrans Intensificadores para Raios X
17.
Invest Radiol ; 28(3): 231-4, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8486490

RESUMO

RATIONALE AND OBJECTIVES: The effect of varying exposure parameters on the detectability of a fracture with digital and conventional radiography were examined. METHODS: A macerated fractured skull was imaged by film-screen radiography (FSR) and digital storage phosphor radiography (DR) with various exposure values. Five radiologists traced the course of a fracture line. The length of the fracture was reported and the results were analyzed by Student's t test for paired samples. RESULTS: At 35% of the conventional radiation dose, the standard DR screen displayed an average of 48% of the fracture length. The difference from the conventional image (45%) was not significant in this case. An increase of the dose to ten times the conventional dose (250 mAs) yielded no significant improvement in the detectability of the length of the fracture (51%). CONCLUSIONS: This experiment shows that with use of the DR with the standard screen, a dose reduction of approximately 35% appears to be possible without any resulting loss of image quality compared to FSR. Use of the high resolution screens should be avoided, since they require a higher incident image dose than standard screens without offering any diagnostic advantages. The image dose of digital radiographs can be roughly estimated based on the digital device sensitivity value. As a rule, the sensitivity value should range between 100 and 200.


Assuntos
Intensificação de Imagem Radiográfica , Fraturas Cranianas/diagnóstico por imagem , Técnicas In Vitro , Doses de Radiação , Sensibilidade e Especificidade
18.
Int J Impot Res ; 15(1): 44-52, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12605240

RESUMO

A total of 76 male patients on renal replacement therapy (RRT) were investigated. Erectile dysfunction (ED) was defined as insufficient erection during visual erotic stimulation (VES) or during sleep as measured with Rigiscan and Erectiometer. Data on medical history, physical examination, and laboratory variables were collected. Furthermore, penile pharmacological duplex ultrasonography (PPDU) was performed. Univariate and multivariate logistic regressions were used to determine prognostic values and to develop prognostic models. Independent prognostic factors for ED were the number of cardiovascular events, waist-hip ratio, body mass index, and acceleration time (AT) as measured with PPDU. Independent prognostic factors for an abnormal AT (>100 ms) were number of cardiovascular events, age category, and the presence of carotid bruits. Independent prognostic factors for insufficient veno-occlusion during PPDU were number of cardiovascular events and supine diastolic blood pressure. The vascular contribution to ED in patients on RRT is substantial. Data from medical history, limited physical examination, and PPDU contribute to the prediction of the vascular contribution to ED.


Assuntos
Disfunção Erétil/diagnóstico , Falência Renal Crônica/complicações , Terapia de Substituição Renal , Adolescente , Adulto , Idoso , Arteriosclerose/complicações , Disfunção Erétil/complicações , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Inquéritos e Questionários
19.
J Hum Hypertens ; 12(6): 345-50, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9705034

RESUMO

OBJECTIVE: To determine reproducibility figures of dynamic arterial wall properties such as cross-sectional compliance (CC) and distensibility (DC) in subjects with increased cardiovascular risk, in comparison with healthy adults. METHODS: A total of 34 persons were divided into three groups with varying cardiovascular risk factors. Diameters (D) and diameter changes (deltaD) during the heart cycle of both common carotid (CCA) and right common femoral (CFA) arteries were measured by a vessel wall movement detector system. Blood pressures (BP) were recorded non-invasively by a semi-automated oscillometric device. CC (=piD(deltaD/2deltaP) in unit mm2/kPa) and DC (=2deltaD/D)/deltaP in unit 10(-3)/kPa) were calculated from the above-mentioned parameters. Measurements were performed twice during one visit and twice again with a time interval of at least 3 days to determine intra-observer intra- and intersession variability. RESULTS: Reproducibility figures of CC and DC of the CCA varied between 8 and 12%, and between 13 and 22% for the CFA. Intra-observer intra- and intersession variability were similar in the three groups. CONCLUSIONS: In our studies the reproducibility of dynamic vascular wall properties determined by ultrasound was good. Despite differences in the absolute values for CC and DC in groups with increased cardiovascular risk, mean reproducibility figures remained at a similar level (8-12%) as in healthy volunteers.


Assuntos
Artérias/fisiopatologia , Doenças Cardiovasculares/diagnóstico , Adulto , Doenças Cardiovasculares/fisiopatologia , Artéria Carótida Primitiva/fisiopatologia , Técnicas de Diagnóstico Cardiovascular , Elasticidade , Feminino , Artéria Femoral/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Fatores de Risco
20.
J Hum Hypertens ; 15(10): 685-91, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11607798

RESUMO

BACKGROUND: Hypertension is an established risk factor for cardiovascular disease. Risk factor patterns for various cardiovascular complications are different. We studied the relationship between increasing diastolic blood pressure and arterial wall dynamics of various peripheral arteries in hypertensives to increase insight in the variability of properties within the arterial tree. METHODS: Eighty-six untreated hypertensives participated in this cross-sectional study. The study-population was divided into quartiles with increasing diastolic office blood pressure. Cross-sectional compliance and distensibility coefficients of the carotid and femoral arteries were determined, using a vessel wall movement detector system (Wall Track System). RESULTS: Diameters of both common carotid arteries enlarged (right: from 7.4 +/- 0.2 to 7.9 +/- 0.2 mm) while cross-sectional compliance (right: from 0.61 +/- 0.04 to 0.42 +/- 0.04 mm(2)/kPa) and distensibility coefficients (right: from 14.2 +/- 1.0 to 9.0 +/- 1.0 10(-3)/kPa) gradually dropped with increasing diastolic blood pressure. Cross-sectional compliance and diameter of the right common femoral artery remained unchanged while distensibility coefficient decreased although less gradually when compared with the carotid arteries. CONCLUSIONS: In untreated hypertensives gradual arterial wall stiffening of the carotid arteries occurred with increasing diastolic blood pressure. Gradual changes were less clear in the common femoral artery which points to the heterogeneity of the arterial tree.


Assuntos
Arteriosclerose/etiologia , Arteriosclerose/fisiopatologia , Pressão Sanguínea/fisiologia , Hipertensão/complicações , Hipertensão/fisiopatologia , Adulto , Arteriosclerose/patologia , Artéria Carótida Primitiva/patologia , Artéria Carótida Primitiva/fisiopatologia , Estudos Transversais , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Feminino , Artéria Femoral/patologia , Artéria Femoral/fisiopatologia , Hemodinâmica/fisiologia , Humanos , Hipertensão/patologia , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco
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