RESUMO
We investigated the evolution of the Asian francolins, five little known species in the genus Francolinus (Phasianidae). Evolutionary affinities of two of these species, F. gularis (swamp francolin) and F. pondicerianus (grey francolin), has long remained unclear. In contrast, the other three species, F. pintadeanus (Chinese francolin), F. pictus (painted francolin) and F. francolinus (black francolin) have been cast among the "spotted francolins" on a morphological and ecological basis. Previous molecular DNA investigations including Asian francolins mostly relied upon partial gene sequencing of one specimen per species (no more than three species and with the exclusion of F. pictus). Therefore, fundamental questions do persist. What relationship exists among the spotted and the other Asian francolins? What is the geographic origin of the black francolin, the species with the largest distribution range? How did the geological history influence the diversification of francolins across Asia? We sequenced the entire Control Region of the mitochondrial DNA in 228 samples of all five Asian francolin species, which were collected in 16 countries (from East Europe to East Asia). We constructed a molecular phylogeny according to four different procedures. We showed the monophyly of each of the Asian francolins and the spotted group, while that of the entire Asian group was presumed according to a biogeographical model we proposed. The splitting of the genus Francolinus occurred ~17.4 Ma (95% HPD: 13.4-22.1) while the spotted francolins diverged ~10.5 Ma (7.0-14.9). We resolved the most recent common ancestor to painted and black francolin as being in the Indian sub-continent, thus suggesting a westwards adaptive radiation of the latter. In Pakistan, we identified F. f. asiae representatives in the Northern Areas and in the Sindh. The latter represents a relict population of Indian fauna within the Pakistani range of the Great Rann of Kachchh.
Assuntos
Evolução Molecular , Galliformes/classificação , Especiação Genética , Filogenia , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Galliformes/genética , Funções Verossimilhança , Filogeografia , Análise de Sequência de DNARESUMO
Owing to its temperature dependence and low vagility, the asp viper (Vipera aspis) is an interesting model species to study the effects of Pleistocene climatic fluctuations on vertebrate genomes. We genotyped 102 specimens from the whole Italian distribution range at three mitochondrial DNA regions (2278 characters, total) and six microsatellite DNA loci (Short Tandem Repeats, STR). The molecular phylogeny was constructed according to Bayesian, Neighbour Joining, Maximum Parsimony and Maximum Likelihood procedures. All methods grouped individuals of the three morphological subspecies (V. a. aspis, V. a. francisciredi, V. a. hugyi) into five different haploclades. Specimens assigned to hugyi clustered in two highly differentiated clades, one being sister group to the complex comprising the second clade of hugyi (i.e., a paraphyletic status), plus two clades of francisciredi. The Bayesian clustering of the STR variability disclosed only two groups, the first including aspis and francisciredi, the second all hugyi. Introgressive hybridization and capture of francisciredi-like lineages in the hugyi mitochondrial genome were suggested to explain the discordance between mitochondrial and nuclear data. The phylogeographic pattern was compatible with population contractions in three glacial refuges. Plausibility of derived hypothesis was checked using coalescence simulations as post hoc tests. Long-term drift and serial founder effects, rather than selection, appeared the main factors affecting the genetic make-up of the Italian asp viper.
Assuntos
DNA Mitocondrial/genética , Evolução Molecular , Filogenia , Viperidae/genética , Animais , Teorema de Bayes , Efeito Fundador , Deriva Genética , Variação Genética , Genética Populacional , Geografia , Itália , Funções Verossimilhança , Repetições de Microssatélites , Modelos Genéticos , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie , Viperidae/classificaçãoRESUMO
The interactions between Cu(II) ions and heparin were investigated using several complementary spectroscopic techniques. NMR indicated an initial binding phase involving specific coordination to four points in the structure that recur in slightly different environments throughout the heparin chain; the carboxylic acid group and the ring oxygen of iduronate-2-O-sulfate, the glycosidic oxygen between this residue and the adjacent (towards the reducing end) glucosamine and the 6-O-sulfate group. In contrast, the later binding phase showed little structural specificity. One- and two-dimensional correlated FTIR revealed that complex out of phase (asynchronous) conformational changes also occurred during the titration of Cu(II) ions into heparin, involving the CO and N-H stretches. EPR demonstrated that the environments of the Cu(II) ions in the initial binding phase were tetragonal (with slightly varied geometry), while the later non-specific phases exhibited conventional coordination. Visible spectroscopy confirmed a shift of the absorbance maximum. Titration of Cu(II) ions into a solution of heparin indicated (both by analysis of FTIR and EPR spectra) that the initial binding phase was complete by 15-20 Cu(II) ions per chain; thereafter the ions bound in the non-specific mode. Hetero-correlation spectroscopy (FTIR-CD) improved resolution and assisted assignment of the broad CD features from the FTIR spectra and indicated both in-phase and more complex out of phase (synchronous and asynchronous, respectively) changes in interactions within the heparin molecule during the titration of Cu(II) ions.
Assuntos
Cátions Bivalentes/química , Cobre/química , Heparina/química , Dicroísmo Circular , Espectroscopia de Ressonância de Spin Eletrônica , Ressonância Magnética Nuclear Biomolecular , Espectroscopia de Infravermelho com Transformada de Fourier/métodosRESUMO
Endometrial carcinoma is the most commonly reported gynaecologic malignancy in industrialized countries. Traditionally the surgical treatment of endometrial cancer is total abdominal hysterectomy, bilateral salpingo-oophorectomy, and peritoneal washing cytology. Alternative surgical procedures have been proposed compared to abdominal hysterectomy: increased number of issues about laparoscopy shows the common trend to use this technique. Literature largely described advantages of the laparoscopic procedure compared to abdominal and vaginal surgery. Long-term follow-up series are not available; further investigation into survival and recurrence rates is indicated.
Assuntos
Neoplasias do Endométrio/cirurgia , Histerectomia/métodos , Laparoscopia , Feminino , Humanos , Histerectomia/efeitos adversosRESUMO
Transformation systems for methanogenic archaea are scarce, none has been reported for the genus Methanosarcina, and plasmids useful as vectors for cloning foreign DNA into methanogens that stably replicate as extrachromosomal elements are not available. We developed an integration vector for transformation of a member of the genus Methanosarcina, i.e. Methanosarcina mazei, using a segment (Int alpha; 1015 bp) which encompasses the intergenic region (431 bp) between the stress (heat-shock) genes grpE and dnaK. This segment also includes the 3' end (270 bp) of the grpE protein-coding region and the 5' end (314 bp) of the dnaK protein-coding region. Int alpha has an EcoRI site, useful for cloning, situated in the 3' direction beyond the grpE transcription termination region, and far upstream from the dnaK promoter. This location of the site, and the monocistronic mode of transcription of grpE and dnaK in M. mazei, suggested to us that a foreign insert in the site would not affect transcription of either flanking gene. A puromycin-resistance cassette (pac cassette) was inserted in the EcoRI site of Int alpha already inserted in pUC18, to obtain a vector which integrated the pac cassette in the chromosome between grpE and dnaK. The pac gene was transcribed and the transformants acquired puromycin resistance. Constitutive and heat-shock-induced transcription of grpE and dnaK in the transformants was the same as in wild-type cells. The two vectors found with transforming ability differed in the orientation of the pac cassette but both had M. mazei's DNA on each flank of the cassette, with the same orientation as that of the homologous segments in the chromosome.
Assuntos
DNA Bacteriano/genética , Proteínas de Escherichia coli , Methanosarcina/genética , Transcrição Gênica , Proteínas de Bactérias/genética , Southern Blotting , Cromossomos Bacterianos , Resistência Microbiana a Medicamentos/genética , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Vetores Genéticos , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico/genética , Puromicina/farmacologia , Transformação GenéticaRESUMO
The aim of the present study was to explore the antibacterial activity of the levofloxacin (LVX) and ceftazidime (CAZ) combination compared with the amikacin (AMK)/CAZ combination against Pseudomonas aeruginosa. Minimum inhibitory concentrations (MICs) were determined according to NCCLS. FIC indices (Fl) were calculated by the checkerboard technique. CAZ combined with LVX or AMK yielded Fls indicating synergism (Fl < or = 0.5) for 71/102 (69.6%) and 81/102 (79.4%) (p = 0.108), indifference (FI > 0.5-4) for 24/102 (23.5%) and 12/102 (11.7%) (p = 0.027), and antagonism (Fl > 4) for 7/102 (6.8%) and 9/102 (8.8%) (p = 0.602) strains, respectively. In vivo, CAZ/LVX was as bactericidal as CAZ/AMK combination. Our results support the potential role of LVX as an alternative to AMK in the combination therapy with CAZ in the treatment of P. aeruginosa severe infections. Anyway, further investigations and clinical trials are awaited until any definitive conclusions can be drawn.
Assuntos
Amicacina/farmacologia , Ceftazidima/farmacologia , Quimioterapia Combinada/farmacologia , Levofloxacino , Ofloxacino/farmacologia , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Farmacorresistência Bacteriana , Sinergismo Farmacológico , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos , Testes de Sensibilidade Microbiana , Sensibilidade e EspecificidadeRESUMO
Despite the methodological difficulties of evaluating the role of a single rheological component, some clinical situations characterised by an increase of blood viscosity can be identified. These are classified as 'blood hyperviscosity syndromes' and can be divided into 2 groups. The first includes pathophysiological conditions in which a primary blood abnormality causes a decrease of blood flow, as occurs in polycythaemic, sclerocythaemic and seric hyperviscosity syndromes, and may be referred to as 'primary blood hyperviscosity syndromes'. The second group includes pathological conditions in which a primary reduction of blood supply to tissue provokes tissue ischaemia, and an impairment of rheological properties of blood can be observed at microcirculatory level. Thus, these situations have been described as 'secondary blood hyperviscosity syndromes'. Patients with peripheral obliterative arterial disease, ischaemic cardiopathies and cerebrovascular insufficiencies show a diminution in blood fluidity during spontaneous or provoked ischaemic conditions which disappears after reperfusion of the tissue. The pathogenesis of this rheological damage is unclear, but may arise from the complex relationship among blood cells (red cells, leucocytes, platelets), endothelium and plasma components. In addition to these 2 groups of blood hyperviscosity syndromes, several pathological states such as diabetes, shock, surgery, and rheumatic disease have been described in which an increase of blood viscosity can be observed. For these situations, which require much further investigation, the term 'syndromes associated with blood hyperviscosity' could be proposed.
Assuntos
Viscosidade Sanguínea , Doenças Hematológicas/sangue , Doenças Hematológicas/etiologia , Humanos , SíndromeRESUMO
We have developed a competitive heparin binding assay employing protamine-coated magnetic beads for detection and measurement of heparin. The assay utilizes 125-iodine specifically bound to newly synthesized low-molecular-mass (LMM) heparin-tyramine. The tracer was stable over a period of 3 weeks, as demonstrated by gel filtration chromatography. The protamine-coated beads were found to be stable over at least two months. The heparin-tyramine bead assay had in buffer a lower detection limit of 0.04 microgram/ml and in plasma of 0.23 microgram heparin/ml. 50% binding was obtained at 0.7 microgram/ml and 20% binding at 4 micrograms/ml in plasma. The within assay coefficient of variation ranged from 9 to 28% for unfractionated, high molecular mass (HMM) heparin and from 12 to 15% for LMM-heparins in buffer system and in plasma. Various heparin fractions displaced the tracer from the protamine-coated magnetic beads to different extents. The validity of the assay was proven after intravenous administration of unfractionated and LMM-heparin in man. The elimination rate was similar using the heparin-tyramine bead assay compared with the anti-factor Xa coagulation assay. After intravenous dosing of LMM-heparin the maximal concentration was lower using the heparin-tyramine bead assay compared with the anti-factor Xa coagulation assay. The bead assay was found to be reproducible, valid, and rapid for measurement of the concentration of heparin preparations in purified systems and for HMM-heparin in plasma. Measurement of the concentration of LMM-heparin in plasma has a high coefficient of variation using the binding assay.
Assuntos
Heparina de Baixo Peso Molecular , Heparina/análise , Tiramina , Ligação Competitiva , Humanos , Radioisótopos do Iodo , Magnetismo , Microquímica , Microesferas , Estrutura Molecular , Protaminas , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , TitulometriaRESUMO
13C NMR relaxation measurements at three different magnetic field strengths have been used to analyse the motional properties of a low molecular weight K5 polysaccharide (delta UA-[-->4)-beta-D-GlcNAc(1-->4)-beta-D-GlcA(1-->]n-GlcNAcred) from E. coli. Two-dimensional double INEPT spectra with suppression of cross-correlation effects between dipolar and chemical shift anisotropy relaxation mechanisms were collected in order to determine carbon longitudinal and transverse relaxation times. The values of the overall correlation time and the rate of internal motions were obtained using the model free spectral densities. The data indicate that the overall motion of the molecule is non-isotropic and can be approximated with the symmetric top model with an axial ratio of approximately 22. The magnitude of the generalized order parameters (S2 approximately 0.8) and the internal motion correlation time (tau e approximately 30 ps) differ from those found for iduronic acid-containing glycosaminoglycans and suggest that the internal motions in K5 polysaccharide are more limited.
Assuntos
Escherichia coli/química , Polissacarídeos Bacterianos/química , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Dados de Sequência MolecularRESUMO
1H and 13C NMR relaxation measurements at various magnetic fields have been used to characterize the nature of overall and internal motions in heparin epoxide in aqueous solution. A two-dimensional homonuclear NOESY experiment showed a considerable number of cross-relaxing protons in the molecule. The inter-proton distances calculated from NOE data were compared with those obtained by molecular mechanics calculations. Several discrepancies between the experimental and the theoretical inter-proton distances as well as the variations in 13C spin-lattice relaxation times, measured at two magnetic fields, indicated that the polysaccharide tumbles anisotropically in solution. The rates of overall and internal motions as well as the order parameters have been calculated using a model-free spectral density function. The numerical values indicate that the correlation times which characterize overall molecular motion are outside the extreme narrowing limit (tau parallel = 8 x 10(-10) s and tau perpendicular = 4.2 x 10(-8) s) and that internal motion correlation time is on a picosecond timescale.
Assuntos
Compostos de Epóxi/química , Heparina/análogos & derivados , Heparina/química , Configuração de Carboidratos , Sequência de Carboidratos , Compostos de Epóxi/metabolismo , Heparina/metabolismo , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Estrutura MolecularRESUMO
The complete 1H and 13C NMR spectral assignments are described for the most prevalent patterns of sulfation and acetylation which can be found in polymeric heparin or can be obtained by standard chemical modifications. These include a number of novel structures containing unsubstituted or acetylated amino groups and the first complete NMR assignments of many of the other derivatives. Beef lung heparin was chosen as a model system and studies were carried out using conditions to control the influences on the chemical shift positions in heparin samples of divalent cations and variations in pH and temperature.
Assuntos
Heparina/química , Acetilação , Animais , Bovinos , Heparina/análogos & derivados , Pulmão/química , Espectroscopia de Ressonância Magnética , Sequências Repetitivas de Ácido Nucleico , Sulfatos/químicaRESUMO
O-Sulfation of sulfaminoheparosan SAH, a glycosaminoglucuronan with the structure-->4)-beta-D-GlcA(1-->4)-beta-D-GlcNSO3(-)-(1-->, obtained by N-deacetylation and N-sulfation of the capsular polysaccharide from E. coli K5, was investigated in order to characterize the sulfation pattern eliciting heparin-like activities. SAH was reacted (as the tributylammonium salt in N,N-dimethylformamide) with pyridine-sulfur trioxide under systematically different experimental conditions. The structure of O-sulfated products (SAHS), as determined by mono- and two-dimensional 1H and 13C NMR, varied with variation of reaction parameters. Sulfation of SAH preferentially occurred at O-6 of the GlcNSO3- residues. Further sulfation occurred either at O-3 or at O-2 of the GlcA residues, depending on the experimental conditions. Products with significantly high affinity for antithrombin and antifactor Xa activity were obtained under well-defined conditions. These products contained the trisulfated aminosugar GlcNSO3-3,6SO3-, which is a marker component of the pentasaccharide sequence through which heparin binds to antithrombin.
Assuntos
Escherichia coli/imunologia , Heparina , Polissacarídeos Bacterianos/química , Configuração de Carboidratos , Sequência de Carboidratos , Escherichia coli/química , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética/métodos , Dados de Sequência Molecular , Polissacarídeos Bacterianos/isolamento & purificação , Ácidos Sulfúricos/análiseRESUMO
1H, 13C NMR chemical shifts and 1J(CH) coupling constants were measured for derivatives of heparin containing various sulfation patterns. 1H and 13C chemical shifts varied considerably after introducing electronegative sulfate groups. Chemical shifts of protons linked to carbons changed by up to 1 ppm on substitution with O- and N-sulfate or acetyl groups. Differences up to 10 ppm were detected for 13C chemical shifts in substituted glucosamine, but a less clear dependence was found in iduronate. 1J(CH) values formed two groups, corresponding to either sulfation or non-sulfation at positions 2 and 3 of glucosamine. O-sulfation caused increases up to 6 Hz in 1J(CH) and N-sulfation decreases up to 4 Hz. N-acetylation gave similar 1J(CH) values to N-sulfation. At positions 2 and 3 of iduronate the trend was less marked; 1J(CH) for O-sulfated positions usually increasing. Introduction of sulfate groups influences chemical shift and 1J(CH) values at the position of substitution, but also at more remote positions. 1J(CH) at the glycosidic linkage positions varied between free-amino and N-sulfated compounds, by up to 9 Hz. These results and changes in chemical shift values suggest that iduronate residues and the glycosidic linkages are affected, indicating overall conformational change. This may have important implications for biological activities.
Assuntos
Heparina/química , Ressonância Magnética Nuclear Biomolecular/métodos , Acetilação , Configuração de Carboidratos , Isótopos de Carbono , Glucosamina/química , Heparina/análogos & derivados , Hidrogênio , Ácido Idurônico/química , Sulfatos/químicaRESUMO
With the aid of heparinase and heparitinases from Flavobacterium heparinum and 13C and IH NMR spectroscopy it was shown that the heparan sulphate isolated from the brine shrimp Artemia franciscana exhibits structural features intermediate between those of mammalian heparins and heparan sulphates. These include an unusually high degree of N-sulphation (with corresponding very low degree of N-acetylation), a relatively high content of iduronic acid residues (both unsulphated and 2-O-sulphated) and a relatively low degree of 6-O-sulphation of the glucosamine residues. The major sequences (glucuronic acid-->N-sulphated glucosamine and glucuronic acid-->N, 6-disulphated glucosamine) are most probably arranged in blocks. Although exhibiting negligible anticlotting activity in the APTT and anti-factor Xa assays the A. franciscana heparan sulphate has a high heparin cofactor-II activity (about 1/3 that of heparin).
Assuntos
Artemia/química , Cofator II da Heparina/metabolismo , Heparitina Sulfato/metabolismo , Animais , Carboidratos/química , Bovinos , Eletroforese em Gel de Ágar , Heparitina Sulfato/química , Heparitina Sulfato/isolamento & purificação , Peso Molecular , Ressonância Magnética Nuclear Biomolecular , Ácidos Urônicos/químicaRESUMO
Blood, plasma and serum viscosity, packed red cell volume, and plasma fibrinogen concentration was measured in a group of 13 subjects, suffering from peripheral obliterative arterial disease of the lower limbs (stage III or IV), awaiting surgery, and in 9 control subjects, none of whom showed signs of circulatory disease of the lower limbs either by clinical examination or by instrumental measurements. The blood samples were taken from the: (a) antecubital vein; (b) femoral vein; (c) femoral artery. In the patients venous blood viscosity was significantly higher than arterial blood viscosity. No significant differences have been found between the femoral and the antecubital vein, but in the femoral vein blood viscosity was slightly higher. Packed red cell volume and plasma viscosity were slightly but significantly higher in venous blood, while no difference was seen in serum viscosity and in plasma fibrinogen concentration. In the control subjects blood viscosity values were decidedly lower than in patients and no statistically significant differences were to be found between artery and vein, even if viscosity values were lower in artery. These results support the hypothesis that an interrelation exists between hyperivscosity syndrome and vascular ischaemia-inducing diseases.
Assuntos
Arteriopatias Oclusivas/sangue , Viscosidade Sanguínea , Perna (Membro)/irrigação sanguínea , Adulto , Idoso , Artérias , Feminino , Fibrinogênio/análise , Hematócrito , Humanos , Masculino , Pessoa de Meia-Idade , VeiasRESUMO
Acute critical limb ischemia (CLI) is a rather frequent clinical event in elderly patients. Atherosclerotic plaques or cardiopathies (atrial enlargement and fibrillation, ventricular thrombosis) are the most frequent clinical situations related to peripheral embolization. Rapid diagnosis followed by suitable treatment allows us to obtain good results even in elderly patients. The decision about the treatment of acute CLI is related to the clinical and functional condition of the patient. Anamnesis must inquire about recent ischemic or hemorrhagic events in the cardiovascular, gastro-intestinal and urinary apparatuses, or the presence of disorders of coagulation and fibrinolysis. An objective clinical examination and a multidimensional assessment must evaluate the degree of functional impairment and provide the basis of a therapeutic strategy (cost/benefit ratio). Diagnostic examination in the frail elderly patient (FP) involves only the ultrasonographic method, to localize the level of thromboembolic occlusion, which is followed by angiography in the non-frail patient (NFP). In the case of proximal occlusion (of the iliac or femoro-popliteal arteries), the elective treatment in both groups of patients is thromboendarterectomy, plus transcutaneous angioplastics or by-pass in NFP, followed by prostacyclin or heparin infusions. Distal occlusion (below the popliteal artery) in FP is treated only with prostacyclin or heparin, whereas in NFP, fibrinolysis is the elective treatment, followed by prostacyclin or heparin. In the cases of distal gangrene, before amputation is performed, a "limb salvage" operation must be considered. After the acute phase of medical or surgical treatment, vasoactive or antiplatelet drugs are employed in FP, whereas in NFP the use of coumadin is the preferred treatment to counteract the rethrombosis and prevent new embolizations. Antiplatelet therapy could be selected when coumadin is contra-indicated.
RESUMO
A double blind placebo-controlled randomised crossover study was performed with Pentoxifylline (Trental 400 tablets with 400 mg active ingredient) in 24 patients (19 males, 5 females, aged between 40 and 71 years) suffering from peripheral occlusive arteriopathy of stage II severity (Fontaine's classification). In 12 patients (group I) the treatment was started with placebo, and in another 12 subjects with Pentoxifylline (group II). The dosage was 3 tablets of either formulation t.d.s., the treatment periods were 8 weeks each with a two week washout between. The standardised walking test (120 steps/min under metronome control) was used for the assessment of the walking capacity. There was a significant 60% increase in pain-free walking distance in either Pentoxifylline treatment periods, whereas there were no clinically relevant changes in the placebo periods. When comparing the two starting periods only, there was an increase in the Pentoxifylline group from 223 to 359 m on average and in the placebo group from 208 to 215 m, patients in both groups being comparable at basal level as to the distribution of sex, age, location of occlusion, duration of disease as well as in respect to the walking capacity. No adverse reactions were recorded during the trial.
Assuntos
Ensaios Clínicos como Assunto , Claudicação Intermitente/tratamento farmacológico , Pentoxifilina/uso terapêutico , Teobromina/análogos & derivados , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , PlacebosRESUMO
This study was aimed at revealing the relationship between the serum concentrations of lipoprotein(a) [Lp(a)], the coronary atherosclerotic disease (CAD) and the cerebral vasculopathies (CVP) in elderly patients. A group of 117 patients (66 women and 51 men, mean age 83 +/- 5.8 years) was investigated. Of them, 58 suffered from acute myocardial infarct (AMI) and 59 from ictus cerebri (IC). The parameters were compared with those obtained from a control-group of 88 old people without any recent clinical history of cerebrovasculopathy or atherosclerotic coronariopathy. In the patients with AMI, the average serum value of Lp(a) was 40.8 +/- 18.5 mg%, and in those suffering from IC, it was 46.7 +/- 13.2 mg%; the differences of these averages against the mean found in the control patients (23.2 +/- 11.5 mg%) were statistically significant (p < 0.01). One can conclude that an increased Lp(a) is of diagnostic value for the presence of both IC and AMI, and represents a risk factor for cerebrovasculopathies, too.
RESUMO
The infusion of isoxsuprine was followed by an increase of heart rate and calf blood flow and by a decrease of arterial diastolic pressure and blood viscosity both in normal controls and patients with peripheral obstructive arterial disease. The pre-treatment with a non-selective beta adrenoceptor blocker (propranolol) canceled all the isoxsuprine-dependent changes, while the pre-treatment with a selective beta adrenoceptor blocker (metoprolol) abolished only tachycardia and did not influence the increase of calf blood flow and the decrease of blood viscosity. These findings indicate the different role of vascular beta receptors in the regulation of muscular blood flow and suggest the pharmacologic possibility to unmask the beta2-dependent vasodilation.
Assuntos
Arteriopatias Oclusivas/tratamento farmacológico , Isoxsuprina/uso terapêutico , Metoprolol/uso terapêutico , Propanolaminas/uso terapêutico , Propranolol/uso terapêutico , Adulto , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea/efeitos dos fármacos , Interações Medicamentosas , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Taquicardia/tratamento farmacológicoRESUMO
Studies were carried out to investigate the effects of pentoxifylline on various hemorheological (whole blood, plasma and serum viscosity, erythrocyte filtrability, hematocrit), hemostasiological (blood coagulation and fibrinolysis: euglobulin lysis time, fibrinogen, plasminogen, alpha-2-macroglobulin, alpha-1-antitrypsin, antiplasmin; platelet function: beta-thromboglobulin), and hemodynamic factors (limb perfusion: rest and peak flow, time to peak flow; systemic blood pressure, heart rate). In addition, clinical efficacy was monitored in patients with claudication by assessing walking capacity under placebo controlled double blind cross over conditions. The investigations disclosed the positive influence of acute and chronic pentoxifylline administration on hemorheological, hemostasiological and perfusion parameters, most of the changes recorded being statistically significant. The clinical benefit of pentoxifylline (Trental 400) treatment was demonstrated by the significantly superior increase in walking capacity in comparison to placebo in the controlled study.