RESUMO
Increased risk of vasospasm, a spontaneous hyperconstriction, is associated with atherosclerosis, cigarette smoking, and hypertension-all conditions involving oxidative stress, lipid peroxidation, and inflammation. To test the role of the lipid peroxidation- and inflammation-derived aldehyde, acrolein, in human vasospasm, we developed an ex vivo model using human coronary artery bypass graft (CABG) blood vessels and a demonstrated acrolein precursor, allylamine. Allylamine induces hypercontraction in isolated rat coronary artery in a semicarbazide-sensitive amine oxidase activity (SSAO) dependent manner. Isolated human CABG blood vessels (internal mammary artery, radial artery, saphenous vein) were used to determine: (1) vessel responses and sensitivity to acrolein, allylamine, and H(2)O(2) exposure (1 microM-1 mM), (2) SSAO dependence of allylamine-induced effects using SSAO inhibitors (semicarbazide, 1 mM; MDL 72274-E, active isomer; MDL 72274-Z, inactive isomer; 100 microM), (3) the vasoactive effects of two other SSAO amine substrates, benzylamine and methylamine, and (4) the contribution of extracellular Ca(2+) to hypercontraction. Acrolein or allylamine but not H(2)O(2), benzylamine, or methylamine stimulated spontaneous and pharmacologically intractable hypercontraction in CABG blood vessels that was similar to clinical vasospasm. Allylamine-induced hypercontraction and blood vessel SSAO activity were abolished by pretreatment with semicarbazide or MDL 72274-E but not by MDL 72274-Z. Allylamine-induced hypercontraction also was significantly attenuated in Ca(2+)-free buffer. In isolated aorta of spontaneously hypertensive rat, allylamine-induced an SSAO-dependent contraction and enhanced norepinephrine sensitivity but not in Sprague-Dawley rat aorta. We conclude that acrolein generation in the blood vessel wall increases human susceptibility to vasospasm, an event that is enhanced in hypertension.
Assuntos
Acroleína/farmacologia , Alilamina/farmacologia , Vasos Sanguíneos/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Acroleína/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Compostos Alílicos/farmacologia , Amina Oxidase (contendo Cobre)/antagonistas & inibidores , Amina Oxidase (contendo Cobre)/metabolismo , Animais , Aorta/efeitos dos fármacos , Aorta/fisiologia , Vasos Sanguíneos/metabolismo , Relação Dose-Resposta a Droga , Antagonismo de Drogas , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Propilaminas/farmacologia , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Semicarbazidas/farmacologiaRESUMO
It is hypothesized that methylamine (MA) and semicarbazide-sensitive amine oxidase (SSAO) activity are involved in the cardiovascular complications in human diabetics. To test this, we 1) determined the acute vasoactive effects of MA (1-1,000 micromol/l) in uncontracted and norepinephrine (NE; 1 micromol/l)-precontracted human blood vessels used for coronary artery bypass grafts [left internal mammary artery (LIMA), radial artery (RA), and right saphenous vein (RSV)]; 2) tested whether MA effects in LIMA and RSV were dependent on SSAO activity using the SSAO inhibitor semicarbazide (1 mmol/l, 15 min); 3) determined the effects of MA metabolites formaldehyde and hydrogen peroxide in LIMA and RSV; 4) tested whether the MA response was nitric oxide, prostaglandin, or hyperpolarization dependent; 5) measured the LIMA and RSV cGMP levels after MA exposure; and 6) quantified SSAO activity in LIMA, RA, and RSV. In NE-precontracted vessels, MA stimulated a biphasic response in RA and RSV (rapid contraction followed by prolonged relaxation) and dominant relaxation in LIMA (mean +/- SE, %relaxation: 55.4 +/- 3.9, n = 30). The MA-induced relaxation in LIMA was repeatable, nontoxic, and age independent. Semicarbazide significantly blocked MA-induced relaxation (%inhibition: 82.5 +/- 4.8, n = 7) and SSAO activity (%inhibition: 98.1 +/- 1.3, n = 26) in LIMA. Formaldehyde (%relaxation: 37.3 +/- 18.6, n = 3) and H(2)O(2) (%relaxation: 55.6 +/- 9.0, n = 9) at 1 mmol/l relaxed NE-precontracted LIMA comparable with MA. MA-induced relaxation in LIMA was nitric oxide, prostaglandin, and possibly cGMP independent and blocked by hyperpolarization. We conclude that vascular SSAO activity may convert endogenous amines, like MA, to vasoactive metabolites.
Assuntos
Amina Oxidase (contendo Cobre)/metabolismo , Formaldeído/farmacologia , Peróxido de Hidrogênio/farmacologia , Artéria Torácica Interna/fisiologia , Metilaminas/farmacologia , Músculo Liso Vascular/fisiologia , Vasoconstritores/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Animais , Feminino , Humanos , Técnicas In Vitro , Cinética , Masculino , Artéria Torácica Interna/efeitos dos fármacos , Artéria Torácica Interna/crescimento & desenvolvimento , Pessoa de Meia-Idade , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Relaxamento Muscular/efeitos dos fármacos , Relaxamento Muscular/fisiologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/crescimento & desenvolvimento , Ratos , Análise de Regressão , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacosRESUMO
We investigated the safety and potential pharmacodynamic interactions arising from the co-administration of inhaled beta(2)-agonist salbutamol and cilomilast (Ariflo), a new oral phosphodiesterase 4 inhibitor for the treatment of chronic obstructive pulmonary disease and asthma. This was a randomised, double-blind, placebo-controlled, multiple-dose, three-period crossover study involving non-smoking volunteers between the ages of 18 and 50 years. Volunteers were randomly assigned to receive cilomilast plus nebulised salbutamol, cilomilast plus nebulised placebo or placebo plus nebulised salbutamol. Each volunteer received cilomilast (10 mg twice daily) or placebo for 5 days. On day 5, the morning dose of cilomilast or placebo was followed 1 h later with a single dose of nebulised salbutamol (2.5 mg) or placebo. Primary variables were average change from pre- to 1.5 h post-salbutamol or placebo inhalation in blood pressure, pulse rate, 12-lead ECG and total number of heartbeats measured by 4-h Holter ECG. Thirteen volunteers completed the study. There was no evidence of a clinically important pharmacodynamic interaction between cilomilast and salbutamol in healthy volunteers. Both agents were well tolerated. In conclusion, the pharmacodynamic effects associated with salbutamol inhalation were unaffected by co-administration of cilomilast.
Assuntos
3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Agonistas de Receptores Adrenérgicos beta 2 , Agonistas Adrenérgicos beta/farmacologia , Albuterol/farmacologia , Broncodilatadores/farmacologia , Administração por Inalação , Administração Oral , Adolescente , Agonistas Adrenérgicos beta/administração & dosagem , Agonistas Adrenérgicos beta/efeitos adversos , Adulto , Albuterol/efeitos adversos , Albuterol/sangue , Pressão Sanguínea/efeitos dos fármacos , Broncodilatadores/administração & dosagem , Broncodilatadores/efeitos adversos , Ácidos Carboxílicos , Estudos Cross-Over , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Ácidos Cicloexanocarboxílicos , Método Duplo-Cego , Interações Medicamentosas , Eletrocardiografia Ambulatorial , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas , Fatores de TempoRESUMO
BACKGROUND: Container integrity is critical for maintaining sterility of cryopreserved cellular therapy products. We investigated a series of catastrophic bag failures, first noticed in early 2001. METHODS: Process records were reviewed for all PBPC and lymphocyte products cryopreserved in bags from January 2000 through April 2002. Patient charts were also reviewed. RESULTS: One thousand two hundred and four bags were removed from storage for infusion to 261 patients. All products had been cryopreserved in Cryocyte poly(ethylene co-vinyl acetate) (EVA) bags in either 10% DMSO or 5% DMSO and 6% pentastarch. Product volumes were 25-75 mL, and bags were stored with overwrap bags in a liquid nitrogen tank. From January 2000 to April 2001, failure occurred in 10 of 599 (1.7%) bags. From May 2001 to April 2002, 58 of 605 (9.6%) bags failed, typically with extensive fractures that were visible before thaw. Of the 58 that failed, 24 were salvaged by aseptic methods and infused to patients under antibiotic coverage; 10 of those 24 (42%) had positive bacterial cultures. Bag failures were not related to product type, cryoprotectant solution, liquid versus vapor storage, or freezer location. Failures were linked to use of four Cryocyte bag lots manufactured in 2000 and 2001. After replacing these lots with a 1999 Cryocyte lot and with KryoSafe polyfluoroethylene polyfluoropropylene (FEP) bags, no more failures occurred in 75 and 102 bags, respectively, thawed through April 2002. DISCUSSION: High rates of bag failure were associated with four Cryocyte bag lots. No serious adverse patient effects occurred, but bag failures led to microbial contamination, increased product preparation time, increased antibiotic use, and increased resource expenditure to replace products.
Assuntos
Criopreservação/instrumentação , Criopreservação/métodos , Células-Tronco/metabolismo , Adolescente , Adulto , Idoso , Antígenos CD34/metabolismo , Assepsia/instrumentação , Assepsia/métodos , Bacillus/isolamento & purificação , Criança , Corynebacterium/isolamento & purificação , Criopreservação/estatística & dados numéricos , Contaminação de Equipamentos/economia , Contaminação de Equipamentos/estatística & dados numéricos , Falha de Equipamento/estatística & dados numéricos , Humanos , Infusões Intravenosas , Pessoa de Meia-Idade , Transplante de Células-Tronco de Sangue Periférico/métodos , Transplante de Células-Tronco de Sangue Periférico/estatística & dados numéricos , Plásticos/metabolismo , Plásticos/uso terapêutico , Staphylococcus/isolamento & purificação , Células-Tronco/microbiologia , Preservação de Tecido/instrumentação , Preservação de Tecido/métodos , Preservação de Tecido/estatística & dados numéricos , Coleta de Tecidos e Órgãos/efeitos adversos , Coleta de Tecidos e Órgãos/métodos , Coleta de Tecidos e Órgãos/estatística & dados numéricosRESUMO
The oral pharmacokinetics of cilomilast (Ariflo) were investigated in five separate studies in healthy volunteers. Cilomilast was rapidly absorbed, and pharmacokinetics were dose proportional after single and repeat dosing. The elimination half-life was 7 to 8 hours; accordingly, steady state was reached on the 3rd day of dosing. The degree of accumulation following repeat twice-daily dosing was predictable from the data following a single dose. Although systemic exposure (AUC) was, on average, 21% higher in elderly (65-84 years) compared with young subjects, values for Cmax and t(1/2) were similar, and no difference in tolerability was noted. Single and repeat doses of cilomilast up to and including 15 mg (dosed before or taken between meals) were well tolerated. Dosing with food reduced the rate of absorption without affecting total bioavailability. Hence, tolerability was optimal in the fed state; repeat doses up to and including 30 mg twice daily aftermeals were well tolerated following dose titration.
Assuntos
3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Broncodilatadores/farmacocinética , Inibidores de Fosfodiesterase/farmacocinética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Área Sob a Curva , Broncodilatadores/administração & dosagem , Broncodilatadores/efeitos adversos , Ácidos Carboxílicos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Ácidos Cicloexanocarboxílicos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Interações Alimento-Droga , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas , Inibidores de Fosfodiesterase/administração & dosagem , Inibidores de Fosfodiesterase/efeitos adversosRESUMO
The cervical carcinoma cell line, HeLa S3, was exposed to oestradiol and progesterone separately and combined in ratios similar to those of the luteal and follicular phases of the menstrual cycle. After 48 h of exposure, membrane proteins were extracted from the plasma membrane and analyzed. The lipid composition of the cells and lectin binding patterns to the cells were also assessed. The hormones had a profound effect on the HeLa S3 membrane protein profiles. Progesterone inhibited the synthesis of a wide variety of proteins while oestradiol negated this effect. Less variation between lipid profiles was noted although progesterone reduced the amount of cholesterol present. Differences in lectin binding profiles between the various treatments were noted, indicating an hormonal effect on glycosylation. Such hormonal effects on membrane composition may have implications in cervical susceptible to microbial infections.
Assuntos
Membrana Celular/metabolismo , Estradiol/farmacologia , Progesterona/farmacologia , Membrana Celular/efeitos dos fármacos , Cromatografia , Regulação para Baixo , Glicosilação , Células HeLa , Humanos , Lectinas/metabolismo , Metabolismo dos Lipídeos , Fatores de Tempo , Regulação para CimaRESUMO
Augmentation of selective serotonin reuptake inhibitors (SSRIs) therapy by the 5-HT(1A) receptor agent pindolol may reduce the delay between initiation of antidepressant treatment and clinical response. This hypothesis is based on the ability of pindolol to block 5-HT(1A) autoreceptors in the dorsal raphe nuclei (DRN) and to potentiate the increase in 5-HT transmission induced by SSRIs. However, placebo-controlled clinical studies of pindolol augmentation of antidepressant therapy have reported inconsistent results. Here, we evaluated the occupancy of 5-HT(1A) receptors during treatment with pindolol controlled release (CR) in nine healthy volunteers with Positron Emission Tomography and [11C]WAY 100635. Subjects were studied four times: at baseline, following one week of pindolol CR 7.5 mg/day (4 and 10 hrs post dose), and following one dose of pindolol CR 30 mg(4 hrs post dose). Occupancy of the DRN was 40 +/- 29% on scan 2, 38 +/- 26% on scan 3, and 64 +/- 15% on scan 4. The average occupancy in all other regions was significantly lower at each doses (18 +/- 5% on scan 2, 12 +/- 3% on scan 3, and 42 +/- 4% on scan 4). These results suggest that the blockade in the DRN reached in clinical studies (7.5 mg/day) might be too low and variable to consistently augment the therapeutic effect of SSRIs. However, these data indicate that pindolol exhibits in vivo selectivity for the DRN 5-HT(1A) autoreceptors. As DRN selectivity is desirable for potentiation of 5-HT function, this observation represents an important proof of concept for the development of 5-HT(1A) agents in this application.
Assuntos
Transtornos do Humor/tratamento farmacológico , Pindolol/farmacologia , Piperazinas/uso terapêutico , Piridinas/uso terapêutico , Núcleos da Rafe/metabolismo , Receptores de Serotonina/efeitos dos fármacos , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Adulto , Antidepressivos/uso terapêutico , Encéfalo/efeitos dos fármacos , Humanos , Cinética , Imageamento por Ressonância Magnética , Masculino , Pindolol/administração & dosagem , Pindolol/sangue , Pindolol/uso terapêutico , Piperazinas/sangue , Piperazinas/farmacocinética , Piridinas/sangue , Piridinas/farmacocinética , Receptores de Neurotransmissores/fisiologia , Receptores 5-HT1 de Serotonina , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Transmissão Sináptica/fisiologia , Tomografia Computadorizada de EmissãoRESUMO
Preclinical studies in rodents suggest that augmentation of serotonin reuptake inhibitors (SSRIs) therapy by the 5-hydroxytryptamine(1A) (5-HT(1A)) receptor agent pindolol might reduce the delay between initiation of treatment and antidepressant response. This hypothesis is based on the ability of pindolol to potentiate the increase in serotonin (5-HT) transmission induced by SSRIs, an effect achieved by blockade of the 5-HT(1A) autoreceptors in the dorsal raphe nuclei (DRN). However, placebo-controlled clinical studies of pindolol augmentation of antidepressant therapy have reported inconsistent results. Here, we evaluated the occupancy of 5-HT(1A) receptors following treatment with controlled release pindolol in nine healthy volunteers with positron-emission tomography (PET). Each subject was studied four times: at baseline (scan 1), following 1 week of oral administration of pindolol CR (7.5 mg/day) at peak level, 4 h after the dose (scan 2), and at 10 h following the dose (scan 3), and following one dose of pindolol CR (30 mg) (at peak level, 4 h) (scan 4). Pindolol occupancy of 5-HT(1A) receptors was evaluated in the DRN and cortical regions as the decrease in binding potential (BP) of the radiolabelled selective 5-HT(1A) antagonist [carbonyl-(11)C]WAY-100635 or [carbonyl-(11)C] N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridyl)cyclohexa necarboxamide abbreviated as [(11)C]WAY-100635. Pindolol dose-dependently decreased [(11)C]WAY-100635 BP. Combining all the regions, occupancy was 20 +/- 8% at scan 2, 14 +/- 8% at scan 3, and 44 +/- 8% at scan 4. The results of this study suggest that at doses used in clinical studies of augmentation of the SSRI effect by pindolol (2.5 mg t.i.d.), the occupancy of 5-HT(1A) receptors is moderate and highly variable between subjects. This factor might explain the variable results obtained in clinical studies. On the other hand, at each dose tested, pindolol occupancy of 5-HT(1A) receptors was higher in the DRN compared to cortical regions, demonstrating a significant in vivo selectivity for DRN 5-HT(1A) autoreceptors relative to cortico-limbic postsynaptic receptors. This selectivity is necessary for the potentiation of 5-HT transmission, and this finding represents an important proof of concept in the development of 5-HT(1A) agents for this application. Early evaluation of new drugs with PET imaging will enable rapid screening of compounds based on DRN selectivity and more appropriate determination of doses for clinical trials.
Assuntos
Pindolol/metabolismo , Receptores de Serotonina/análise , Antagonistas da Serotonina/metabolismo , Tomografia Computadorizada de Emissão , Adulto , Química Encefálica , Humanos , Masculino , Pessoa de Meia-Idade , Núcleos da Rafe/química , Receptores 5-HT1 de SerotoninaRESUMO
PURPOSE: To describe the pharmacokinetics of SK&F 107647, a synthetic hematoregulatory peptide, in healthy volunteers and in patients with adenocarcinoma. METHODS: SK&F 107647 pharmacokinetics were evaluated in 2 dose-escalation studies. Volunteers received SK&F 107647 as single 15-minute iv infusion doses of 1, 10, 100, 500, and 1,000 microg/kg. Cancer patients received 2-hour iv infusions of 0.001, 0.01, 0.1 and 1 microg/kg once daily for 10 days. Drug concentrations were quantified in plasma and urine of healthy volunteers and on days 1 and 10 in plasma of cancer patients receiving the two top dose levels. RESULTS: In volunteers, mean clearance (CL) ranged from 76.7 to 101 ml/hour/kg; mean volume of distribution at steady-state (Vss) ranged from 175 to 268 ml/kg. Most of the administered dose was renally excreted as intact peptide within 24 hours postinfusion. In patients, mean CL was 57.6 ml/hour/kg, mean Vss ranged from 128 to 150 ml/kg and terminal half-life from 2.1 to 3.4 hours. There was little accumulation of drug. In both studies, linear pharmacokinetics was observed. Clearance approached normal glomerular filtration rate (GFR) in volunteers and correlated with creatinine clearance in cancer patients. CONCLUSIONS: SK&F 107647 exhibits linear pharmacokinetics, a small Vss, and clearance, primarily renal, approaching normal GFR.
Assuntos
Adenocarcinoma/metabolismo , Adjuvantes Imunológicos/farmacocinética , Neoplasias Colorretais/metabolismo , Oligopeptídeos/farmacocinética , Neoplasias Pancreáticas/metabolismo , Adenocarcinoma/sangue , Adenocarcinoma/urina , Adjuvantes Imunológicos/sangue , Adjuvantes Imunológicos/urina , Adulto , Idoso , Estudos de Casos e Controles , Neoplasias Colorretais/sangue , Neoplasias Colorretais/urina , Humanos , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/sangue , Oligopeptídeos/urina , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/urina , RadioimunoensaioRESUMO
Rosiglitazone is a potent peroxisome proliferator-activated receptor gamma agonist that decreases hyperglycemia by reducing insulin resistance in patients with type 2 diabetes mellitus. The disposition of (14)C-labeled rosiglitazone was determined after oral and i.v. dosing of rosiglitazone solution, and the disposition of nonradiolabeled rosiglitazone was determined after oral dosing of tablets in this open-label, three-part, semirandomized, crossover study. The absorption of rosiglitazone was rapid and essentially complete, with absolute bioavailability estimated to be approximately 99% after oral tablet dosing and approximately 95% after oral solution dosing, and clearance was primarily metabolic. The time to maximal concentration of radioactivity and the elimination half-life for two metabolites in plasma were significantly longer than for rosiglitazone itself (4-6 h versus 0. 5-1 h, and ca. 5 days versus 3-7 h). Radioactivity was excreted primarily via the urine ( approximately 65%) and was excreted similarly after oral and i.v. dosing. The major routes of metabolism were N-demethylation and hydroxylation with subsequent conjugation, of which neither was affected by the route of drug administration. The major metabolites, those of intermediate importance, and nearly all of the trace metabolites in humans have been identified previously in preclinical studies. Rosiglitazone was well tolerated in all formulations.
Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Hipoglicemiantes/farmacocinética , Tiazóis/farmacocinética , Tiazolidinedionas , Adulto , Idoso , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Rosiglitazona , Tiazóis/uso terapêuticoRESUMO
BACKGROUND: Interleukin-5 (IL-5) is essential for the formation of eosinophils, which are thought to have a major role in the pathogenesis of asthma and other allergic diseases. We aimed to assess the effects of monoclonal antibody to IL-5 on blood and sputum eosinophils, airway hyper-responsiveness, and the late asthmatic reaction to inhaled allergen in patients with mild asthma. METHODS: We did a double-blind randomised placebo-controlled trial, in which a single intravenous infusion of humanised (IgG-K) monoclonal antibody to IL-5 (SB-240563) was given at doses of 2.5 mg/kg (n=8) or 10.0 mg/kg (n=8). The effects of treatment on responses to inhaled allergen challenge, sputum eosinophils, and airway hyper-responsiveness to histamine were measured at weeks 1 and 4 with monitoring of blood eosinophil counts for up to 16 weeks. FINDINGS: Monoclonal antibody against IL-5 lowered the mean blood eosinophil count at day 29 from 0.25x10(9)/L (95% CI 0.16-0.34) in the placebo group to 0.04x10(9)/L (0.00-0.07) in the 10 mg/kg group (p<0.0001), and prevented the blood eosinophilia that follows allergen challenge. After inhaled allergen challenge, 9 days after treatment, the percentage sputum eosinophils were 12.2% in the placebo group and lowered to 0.9% (-1.2 to 3.0; p=0.0076) in the 10 mg/kg group, and this effect persisted at day 30 after the dose. There was no significant effect of monoclonal antibody to IL-5 on the late asthmatic response or on airway hyper-responsiveness to histamine. INTERPRETATION: A single dose of monoclonal antibody to IL-5 decreased blood eosinophils for up to 16 weeks and sputum eosinophils at 4 weeks, which has considerable therapeutic potential for asthma and allergy. However, our findings question the role of eosinophils in mediating the late asthmatic response and causing airway hyper-responsiveness.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Asma/terapia , Eosinófilos/metabolismo , Interleucina-5/antagonistas & inibidores , Adulto , Análise de Variância , Testes de Provocação Brônquica , Método Duplo-Cego , Histamina/sangue , Humanos , Infusões Intravenosas , Contagem de Leucócitos , Masculino , Escarro/citologiaRESUMO
BACKGROUND: Chemical biotinylation of red cell membranes may be useful for several clinical applications, including red cell survival studies. STUDY DESIGN AND METHODS: To examine the possible effects of biotinylation on red cell antigens, standard hemagglutination assays were performed on matched sets of control and biotinylated red cells. The red cells were biotinylated at a final concentration of 2.0 pg of sulfo-N-hydroxysuccinimide-biotin per cell, and antigen-negative cells were directly compared to antigen-positive cells when possible. The hemagglutination assays were graded in a blinded fashion. Forty-one red cell antigens from 21 of the 23 established blood group systems were tested. RESULTS: Hemagglutination based upon antibody binding to A, A1, M, N, S, s, P1, D, C, E, c, e, C(w), Lu(b), K, k, Kp(b), Le(a), Le(b), Fy(a), Fy(b), Jk(a), Jk(b), Di(a), Wr(a), Wr(b), Yt(a), Xg(a), Sc1, Do(b), Co(a), Ch, H, Ge2, Cr(a), Kn(a), I, and P was not affected by biotinylation. Unexpectedly, the hemagglutination of Di(b+) and LW(a+) red cells was blocked after biotinylation. Conversely, MH04 monoclonal anti-A agglutinated red cells expressing B only after biotinylation. BIRMA-1 monoclonal anti-A and polyclonal anti-A from sera did not agglutinate the biotinylated B red cells. CONCLUSION: Biotinylation of human red cells specifically modified their antigenicity, as measured by standard hemagglutination assays.
Assuntos
Eritrócitos/imunologia , Isoantígenos/sangue , Biotinilação , Antígenos de Grupos Sanguíneos/imunologia , Testes de Hemaglutinação , Humanos , FenótipoRESUMO
The relationship between the energy source used by HT-29 cells and their state of differentiation was determined. Short chain fatty acids and acetoacetate were applied to the cells for 9 d, after which the medium was replaced with conventional culture medium for a further 9 d so that the permanence of the changes could be assessed (18 d). Glucose utilization and lactic acid, acetoacetate, and beta-hydroxybutyrate production by the cells were determined. Differentiation was assessed by the presence of the enzymes sucrase-isomaltase and carbonic anhydrase 1, as well as morphological changes of the cells. By tracing carbon from acetate, propionate, and butyrate through the cells, it was found that the carbon from the short-chain fatty acids was fluxed into acetoacetate. Significant amounts of acetoacetate were released by the propionate-treated culture after 9 d and the acetate-, propionate-, valerate-, and caproate-treated cultures after 18 d. A significant positive correlation was found between acetoacetate synthesis and differentiation. Acetoacetate applied to HT-29 cells also induced their differentiation. The acetate-, butyrate-, valerate-, isovalerate-, and caproate-treated cells underwent terminal differentiation, while the propionate- and isocaproate-treated cultures underwent programming events. We, therefore, conclude that HT-29 cells utilize short chain fatty acids in preference to glucose, metabolize these to ketones, thereby raising the energy state and effecting the observed morphological and functional changes in the cells.
Assuntos
Metabolismo Energético/fisiologia , Células HT29/citologia , Células HT29/metabolismo , Acetoacetatos/metabolismo , Diferenciação Celular , Ácidos Graxos Voláteis/metabolismo , Glucose/metabolismo , Humanos , Cetonas/metabolismo , Ácido Láctico/metabolismoRESUMO
OBJECTIVE: To determine the plasma antioxidant potential of patients in the intensive care unit (ICU) with severe sepsis and secondary organ dysfunction and relate these findings to outcome. DESIGN: A prospective, cohort study. SETTING: A nine-bed ICU in a university teaching hospital. PATIENTS: Fifteen consecutive patients, who were within 16 hrs of development of severe sepsis and secondary organ dysfunction. INTERVENTIONS: Plasma samples were obtained within 16 hrs of the onset of secondary organ dysfunction and subsequently on days 2, 3, 4, 6, 8, 10, and 15 until patients either left the ICU or died. Plasma antioxidant potential was determined by an ultraviolet spectrophotometric technique. MEASUREMENTS AND MAIN RESULTS: The mean initial plasma antioxidant potential was lower than our range for healthy volunteers (p < .05). Survivors had an initial plasma antioxidant potential that was greater than nonsurvivors (p < .01), and serial subset analysis demonstrated that survivors, despite having a low initial plasma antioxidant potential rapidly attained normal or supranormal values. While plasma antioxidant potential also increased in nonsurvivors over time, values in this subset never reached the normal range and remained below values in survivors at all time points studied (p < .05). CONCLUSIONS: Plasma antioxidant potential is initially decreased in patients with sepsis who develop organ dysfunction, and it increases over time. While we have no clear evidence to prove that this reduction has a causal relationship, failure to achieve a normal plasma antioxidant potential is strongly associated with an unfavorable outcome.
Assuntos
Antioxidantes/metabolismo , Plasma/fisiologia , Sepse/sangue , Sepse/mortalidade , APACHE , Adulto , Estudos de Coortes , Humanos , Unidades de Terapia Intensiva , Pessoa de Meia-Idade , Prognóstico , Estudos ProspectivosRESUMO
OBJECTIVE: To determine antioxidant vitamin concentrations, lipid peroxidation, and an index of nitric oxide production in patients in the intensive care unit (ICU) with septic shock and relate the findings to the presence of secondary organ failure. DESIGN: A prospective, observational study. SETTING: A nine-bed ICU in a University teaching hospital. PATIENTS: Sixteen consecutive patients with septic shock, defined as: a) clinical evidence of acute infection; b) hypo- or hyperthermia (< 35.6 degrees C or > 38.3 degrees C); c) tachypnea (> 20 breaths/min or being mechanically ventilated); d) tachycardia (> 90 beats/min); e) shock (systolic pressure < 90 mm Hg) or receiving inotropes. Fourteen patients also had secondary organ dysfunction. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Antioxidant vitamin concentrations were significantly lower in the patients than the reference range obtained from a comparable group of healthy controls. The mean plasma retinol (vitamin A) concentration was 26.5 +/- 19.3 micrograms/dL compared with 73.5 +/- 18.3 micrograms/dL in healthy subjects (p < .01). Additionally, 13 (81%) patients had retinol values below the lower limit of our reference range (< 37.0 micrograms/dL). Tocopherol (vitamin E) plasma concentrations were below the reference range in all patients (< 9.0 mg/L), with a mean value of 3.6 +/- 2.0 mg/L compared with 11.5 +/- 1.3 mg/L in healthy subjects (p < .001). Plasma beta carotene and lycopene concentrations were undetectable (< 15 micrograms/L) in eight (50%) patients, and below our reference range (< 101 micrograms/L and < 154 micrograms/L, respectively) in the remaining patients. In the five patients with three or more dysfunctional secondary organs, plasma thiobarbituric acid-reactive substances were significantly increased (p < .05), suggesting increased lipid peroxidation. Concentrations of thiobarbituric acid-reactive substances correlated negatively with both plasma retinol and plasma tocopherol (r2 = .42, p < .01 and r2 = .48, p < .005, respectively). In the five patients from whom we were able to collect urine, nitrite excretion was increased approximately 400-fold (p < .001). CONCLUSIONS: These data indicate decreased antioxidant status in the face of enhanced free radical activity, and suggest potential therapeutic strategies involving antioxidant repletion.
Assuntos
Antioxidantes/metabolismo , Peroxidação de Lipídeos , Insuficiência de Múltiplos Órgãos/complicações , Choque Séptico/metabolismo , APACHE , Adolescente , Adulto , Idoso , Carotenoides/sangue , Feminino , Radicais Livres , Humanos , Unidades de Terapia Intensiva , Licopeno , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Choque Séptico/complicações , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Vitamina A/sangue , Vitamina E/sangue , beta CarotenoRESUMO
OBJECTIVE: To investigate the relationship between the soluble derivatives of endothelial adhesion molecules liberated by activated vascular endothelium and the development of the systemic inflammatory response syndrome and organ dysfunction in septic patients. DESIGN: Prospective cohort study with controls. SETTING: University hospital intensive care unit. PATIENTS: Healthy volunteers (controls, n = 85), patients with the systemic inflammatory response syndrome (n = 21), patients with systemic inflammatory response syndrome and organ dysfunction (n = 14), and miscellaneous, severely ill patients (n = 5). INTERVENTIONS: Plasma samples were collected from consecutive patients who satisfied the criteria for inclusion in the groups listed above. MEASUREMENTS AND MAIN RESULTS: The plasma was assayed by enzyme-linked immunosorbent assay (ELISA) for each of the three soluble adhesion molecules: sE-selectin, vascular cell adhesion molecule-1, and intercellular adhesion molecule-1. There were low basal amounts of these adhesion molecules in the healthy volunteers, while plasma concentrations of all three adhesion molecules were increased in the sepsis groups. The median soluble E-selectin concentration was higher in those patients with organ dysfunction compared with the concentrations in patients with uncomplicated sepsis (p < .01 at first and p < .001 when comparing peak values attained). No patient survived when the amount of soluble E-selectin was > 30 units/mL. CONCLUSIONS: Concentrations of circulating vascular endothelial adhesion molecules, especially soluble E-selectin, are increased in patients with systemic inflammatory response syndrome and these concentrations are more increased in patients with organ dysfunction. High plasma concentrations of soluble E-selectin were closely associated with multiple-organ dysfunction and death. Measurement of adhesion molecules, especially soluble E-selectin, might be used to advantage in the management of patients with sepsis.
Assuntos
Infecções Bacterianas/sangue , Moléculas de Adesão Celular/sangue , Proteínas de Membrana/sangue , Insuficiência de Múltiplos Órgãos/sangue , Proteínas do Tecido Nervoso/sangue , Adulto , Infecções Bacterianas/mortalidade , Estudos de Coortes , Selectina E , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Molécula 1 de Adesão Intercelular , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/mortalidade , Estudos Prospectivos , Proteínas R-SNARE , Índice de Gravidade de Doença , SíndromeRESUMO
Mucin histochemistry on sections of colon from germ-free and conventional mouse pups showed that all goblet cell mucins were sulphated at birth. During the first two weeks of post natal development, the pattern of mucin production in the ascending colon changed to a distribution of non-sulphated mucins towards the apical zone of the crypts and sulphated sialomucins basally. In conventional animals during the third postnatal week when the complex micro-flora of the colon was becoming established, the typical adult mucin distribution pattern developed, with sulphated mucins now confined to the upper third of the crypt. However, in the absence of a colonizing micro-flora crypt mucins become more and more sulphated until at weaning, most goblet cells of the ascending colon were producing fully or partially sulphated mucins, except for one or two cells at the very base of the crypt.
Assuntos
Animais Recém-Nascidos/microbiologia , Colo/microbiologia , Mucinas/biossíntese , Animais , Animais Lactentes/microbiologia , Bactérias/crescimento & desenvolvimento , Colo/citologia , Histocitoquímica , Camundongos , Camundongos Endogâmicos C3HRESUMO
The effects of the normal colonizing microflora on postnatal development in the infant mouse were determined by comparison of crypt parameters in histological sections of the ascending colons of conventional specified-pathogen-free mice and their germ-free counterparts. Association of bacteria with the developing colonic mucosa in the third postnatal week caused a lengthening of the crypt column and depressed the total number of secreting goblet cells in each crypt. Thus the increasing bacterial burden during colonization of the developing colon was associated not only with expansion of the proliferative component of the crypt but also with modulation of the relative proportions of crypt cell populations.