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1.
Clin Exp Immunol ; 183(2): 258-70, 2016 02.
Artigo em Inglês | MEDLINE | ID: mdl-26376111

RESUMO

This study's objective was to assess the effects of PD-0360324, a fully human immunoglobulin G2 monoclonal antibody against macrophage colony-stimulating factor in cutaneous lupus erythematosus (CLE). Patients with active subacute CLE or discoid lupus erythematosus were randomized to receive 100 or 150 mg PD-0360324 or placebo via intravenous infusion every 2 weeks for 3 months. Blood and urine samples were obtained pre- and post-treatment to analyse pharmacokinetics and pharmacodynamic changes in CD14(+) CD16(+) monocytes, urinary N-terminal telopeptide (uNTX), alanine/aspartate aminotransferases (ALT/AST) and creatine kinase (CK); tissue biopsy samples were taken to evaluate macrophage populations and T cells using immunohistochemistry. Clinical efficacy assessments included the Cutaneous Lupus Erythematosus Disease Area and Severity Index (CLASI). Among 28 randomized/analysed patients, peak/trough plasma concentrations increased in a greater-than-dose-proportional manner with dose increases from 100 to 150 mg. Statistically significant differences were observed between active treatment and placebo groups in changes from baseline in CD14(+) CD16(+) cells, uNTX, ALT, AST and CK levels at most time-points. The numbers, density and activation states of tissue macrophages and T cells did not change from baseline to treatment end. No between-group differences were seen in CLASI. Patients receiving PD-0360324 reported significantly more adverse events than those receiving placebo, but no serious adverse events. In patients with CLE, 100 and 150 mg PD-0360324 every 2 weeks for 3 months suppressed a subset of circulating monocytes and altered activity of some tissue macrophages without affecting cell populations in CLE skin lesions or improving clinical end-points.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Lúpus Eritematoso Cutâneo/tratamento farmacológico , Lúpus Eritematoso Cutâneo/imunologia , Fator Estimulador de Colônias de Macrófagos/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Administração Intravenosa , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Aspartato Aminotransferases/urina , Colágeno/urina , Creatina Quinase/urina , Método Duplo-Cego , Feminino , Histiócitos/efeitos dos fármacos , Histiócitos/patologia , Humanos , Imuno-Histoquímica , Imunoterapia , Receptores de Lipopolissacarídeos/imunologia , Masculino , Pessoa de Meia-Idade , Receptores de IgG/imunologia , Índice de Gravidade de Doença , Pele/efeitos dos fármacos , Pele/patologia , Adulto Jovem
2.
J Dairy Sci ; 97(9): 5599-607, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25022685

RESUMO

This experiment was conducted to investigate the effects of rumen-protected γ-aminobutyric acid (GABA) on performance and nutrient digestibility in heat-stressed dairy cows. Sixty Holstein dairy cows (141±15 d in milk, 35.9±4.3kg of milk/d, and parity 2.0±1.1) were randomly assigned to 1 of 4 treatments according to a completely randomized block design. Treatments consisted of 0 (control), 40, 80, or 120mg of true GABA/kg of dry matter (DM). The trial lasted 10wk. The average temperature-humidity indices at 0700, 1400, and 2200h were 78.4, 80.2, and 78.7, respectively. Rectal temperatures decreased linearly at 0700, 1400, and 2200h with increasing GABA concentration. Supplementation of GABA had no effect on respiration rates at any time point. Dry matter intake, energy-corrected milk, 4% fat-corrected milk, and milk fat yield tended to increase linearly with increasing GABA concentration. Supplementation of GABA affected, in a quadratic manner, milk protein and lactose concentrations, and milk protein yield, and the peak values were reached at a dose of 40mg of GABA/kg. Milk urea nitrogen concentration responded quadratically. Total solids content increased linearly with increasing GABA concentration. Supplementation of GABA had no effect on milk yield, lactose production, total solids, milk fat concentration, somatic cell score, or feed efficiency. Apparent total-tract digestibilities of DM, organic matter, crude protein, neutral detergent fiber, and acid detergent fiber were similar among treatments. These results indicate that rumen-protected GABA supplementation to dairy cows can alleviate heat stress by reducing rectal temperature, increase DM intake and milk production, and improve milk composition. The appropriate supplemental GABA level for heat-stressed dairy cows is 40mg/kg of DM.


Assuntos
Doenças dos Bovinos/metabolismo , Digestão/efeitos dos fármacos , Transtornos de Estresse por Calor/veterinária , Rúmen/metabolismo , Ácido gama-Aminobutírico/administração & dosagem , Animais , Temperatura Corporal , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Suplementos Nutricionais , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Transtornos de Estresse por Calor/tratamento farmacológico , Transtornos de Estresse por Calor/metabolismo , Temperatura Alta , Lactação/efeitos dos fármacos , Leite/química , Leite/citologia , Proteínas do Leite/análise
3.
J Phys Condens Matter ; 33(43)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34343981

RESUMO

In low-dimensional Ising spin systems, an interesting observation is the presence of step magnetization at low temperatures. Here we combine both DC and pulsed magnetic fields to study the 1/3 magnetization plateau and multiple steps in the Ising spin-chain material α-CoV2O6. Magnetization in pulsed fields is quite different from that in DC fields, showing multiple steps in an intermediate range of 4.2-6 K, inverted hysteresis below 4.2 K and asymmetric magnetization in negative fields below 11 K. We demonstrate that these unusual behaviors in magnetization are caused by the spin dynamics and the anomalous magnetocaloric effect (MCE) in α-CoV2O6, i.e., abrupt changes of sample temperature in adiabatic conditions. We successfully separate the influence between the intrinsic slow spin dynamics and the quasi-extrinsic temperature change. From the MCE, we find that some irreversible behavior is originated from the slow spin dynamics. Two different slow dynamics associated with the metastable steps are observed: one is sensitive to the slow field sweep rate at the order of ∼mT s-1and weakly depends on temperature, while the other responds to the rapid field sweep rate of ∼kT s-1and dominates at lowest temperature. We also distinguish that the metastable transition atH4is the first order and crucial for the ferrimagnetic to ferromagnetic transition. This study is useful to the understanding of multistep magnetization in α-CoV2O6and sheds light on recent experimental findings of related compounds.

4.
J Dairy Sci ; 92(1): 100-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19109268

RESUMO

A new antigen-release device (ARD) that can be implanted to enhance the titer of specific IgG and concentration of total IgG in milk of lactating cows was evaluated. An immunostimulating complex-based vaccine in the core of the ARD was made from the adjuvant Quil A and type XIII lipase from Pseudomonas spp. with a polylactide acid capsule that was used to control antigen release. Forty lactating Holstein dairy cows were divided into 2 groups (n = 20). All cows in the test group were implanted in the right iliac lymph node with 3 types of ARD at the same time, which were designed to release antigens on different days. The other group was used as a control with no implantation. The 3 ARD were designed to release the antigen on d 0, 14, and 28 after implantation. Specific IgG titers in whey and serum were measured by indirect ELISA, and total IgG concentrations were measured using sandwich ELISA. The results indicated that ARD implantation brought no negative effects on the health status, production performance of cows, and caused neither subclinical nor acute mastitis. The levels of specific IgG in serum (200,000 +/- 45,000 vs. 1,200 +/- 360) and whey (41,000 +/- 6,000 vs. 820 +/- 210) increased in the cows implanted with ARD. Specific IgG in whey was increased after 9 d. The dynamics of specific IgG titer demonstrated a pattern with the release of the antigen from 3 types of ARD. The average ELISA titer of test group in whey was 41,000 +/- 6,000, which suggested high efficiency of immune milk production caused by the ARD implantation. For total IgG in milk, greater concentration in the test compared with the control cows occurred from 11 to 20 d following implantation. The IgG mass was consistent with the dynamics of specific IgG titer and was higher from 15 to 30 d between test and control group (7.89 +/- 1.34 vs. 6.48 +/- 1.17 g). In conclusion, ARD implantation was effective in improving specific antibody concentration in serum and whey. Furthermore, the whey:serum ratio of specific IgG titer, the milk:serum ratio of total IgG concentration and total IgG mass in milk suggested that a transiently upregulated IgG transfer occurred after ARD implantation.


Assuntos
Vacinas Bacterianas/imunologia , ISCOMs/imunologia , Imunoglobulina G/imunologia , Lipase/administração & dosagem , Lipase/imunologia , Leite/imunologia , Animais , Temperatura Corporal/imunologia , Bovinos , Implantes de Medicamento , Feminino , Imunoglobulina G/análise , Imunoglobulina G/sangue , Lactação , Leucócitos Mononucleares/imunologia , Mastite Bovina/imunologia , Leite/química , Leite/citologia , Leite/metabolismo , Distribuição Aleatória , Fatores de Tempo , Cicatrização/imunologia
5.
J Dairy Sci ; 91(3): 970-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18292252

RESUMO

Lactoferrin (LF) concentrations in the milk with different levels of the somatic cell count score were examined using an ELISA to determine whether milk LF concentration is influenced by parity of the cow, stage of lactation, and the somatic cell count. The study animals were 198 Chinese Holstein cows randomly chosen from more than 1,600 cows in 4 dairy farms in the Beijing area. The cows had shown no sign of mastitis for 2 mo. Daily milk production was recorded, and milk samples were taken from individual cow samples. The LF concentration varied between 31.78 and 485.63 microg/mL in milk from normal animals. Lactoferrin was significantly associated with stage of lactation (r = 0.557) and daily milk production (r = -0.472). Nevertheless, there was no significant relationship with parity. Moreover, milk LF concentration tended to be correlated with the somatic cell count score (r = 0.375). This finding suggests that milk LF may be helpful as an indicator for intramammary infection in dairy cows.


Assuntos
Lactoferrina/análise , Leite/química , Animais , Bovinos , Feminino , Lactação , Mastite Bovina/metabolismo , Leite/citologia , Paridade , Gravidez , Fatores de Tempo
6.
J Vet Med Sci ; 70(8): 819-24, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18772557

RESUMO

The objective of this study was to evaluate the effect of implanting an Antigen Release Devices (ARD) into dairy cows during the lactation cycle to induce an immune response. Subsequently, the concentrations of lactoferrin in serum and milk were measured. Forty healthy adult Chinese Holstein cows were divided into two equal groups: a test group and a control group. Animals in the test group received ARD implants, whereas the control group animals were not treated. An even spread across the two groups was maintained with animal selection based on parity, the lactation days and milk yields. The concentrations of lactoferrin in the serum and milk of all forty animals were measured using an Enzyme-Linked Immunosorbent Assay (ELISA). The results show that the implantation of an ARD did not significantly increase the concentration of lactoferrin in the serum and milk throughout the whole experiment period except on two occasions. The levels of lactoferrin in the milk and serum significantly increased on day 7 and on day 11 after implantation (p<0.05). There was a strong correlation between milk lactoferrin and serum lactoferrin (r=0.564, P<0.01). Three separate ARDs were used releasing its antigen load on day 0, 14 and 28 to induce a primary, secondary and tertiary response respectively. As the significant increases in the lactoferrin levels were only observed after the first ARD release, the effects of lactoferrin appears to be associated with the early phase of the immune response, consistent with its role in the host's innate defense system.


Assuntos
Antígenos/farmacologia , Lactoferrina/metabolismo , Leite/imunologia , Leite/metabolismo , Animais , Anticorpos/sangue , Antígenos/administração & dosagem , Bovinos , Implantes de Medicamento/farmacologia , Feminino , Abrigo para Animais , Lactação , Lactoferrina/sangue , Lipase Lipoproteica/imunologia , Paridade , Gravidez
7.
J Invest Dermatol ; 107(1): 51-6, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8752839

RESUMO

Increased cyclic AMP-phosphodiesterase activity in peripheral blood leukocytes is associated with the immune and inflammatory hyperreactivity that characterizes atopic dermatitis. Atopic phosphodiesterase has high sensitivity to a variety of enzyme inhibitors, suggesting an increased therapeutic advantage. The objective of this study was to use in vitro assays to identify a potent phosphodiesterase inhibitor and then to investigate its effectiveness in treating atopic dermatitis. Leukocyte enzyme activity was measured by radioenzyme assay, whereas prostaglandin E2 and interleukins 10 (IL-10) and 4 (IL-4) were measured in 24-h culture supernatants of mononuclear leukocytes by immunoassays. The effect of a topical phosphodiesterase inhibitor on atopic dermatitis lesional skin was assessed by double-blind, paired comparisons of active drug and placebo ointments applied to symmetrically involved sites over a 28-d period. Using in vitro, assays, we demonstrated the ability of selective high-potency phosphodiesterase inhibitors to reduce prostaglandin E2, IL-10, and IL-4 production in atopic mononuclear leukocyte cultures. We selected the Type 4 phosphodiesterase inhibitor, CP80,633, based on its inhibitory potency, for clinical testing by topical, bilateral paired comparisons in 20 patients with atopic dermatitis and demonstrated significant reductions of all inflammatory parameters. Phosphodiesterase inhibitors modulate several pathways contributing to the exaggerated immune and inflammatory responses, which characterize atopic dermatitis. This in vivo demonstration of anti-inflammatory efficacy may provide a useful alternative to the over-reliance on corticosteroid therapy in atopic disease.


Assuntos
Anti-Inflamatórios/uso terapêutico , Dermatite Atópica/tratamento farmacológico , Inibidores de Fosfodiesterase/uso terapêutico , Administração Tópica , Adulto , Dermatite Atópica/sangue , Dinoprostona/antagonistas & inibidores , Feminino , Humanos , Interleucina-10/antagonistas & inibidores , Interleucina-4/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Inibidores de Fosfodiesterase/classificação
8.
Endocrinology ; 107(5): 1646-8, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6253272

RESUMO

beta-Adrenergic agonists stimulate surfactant release and decrease fluid in lung alveoli of fetuses. Both effects are most evident toward the end of gestation. We used [3H] dihydroalprenolol (DHA) to investigate the development of pulmonary beta-adrenergic receptors in rabbit fetuses and to study the effect of glucocorticoid treatment on the beta-receptor number. In the lung particulate preparation, DHA binding was rapid, reversible, stereoselective, and of high affinity. The order of potency for adrenergic agonists in competing for DHA binding was isoproterenol > epinephrine = norepinephrine, which is typical of interactions at a beta 1-adrenergic receptor. Using DHA, we demonstrated that the concentration of pulmonary beta-receptors increased significantly between 28 and 31 days of gestation; however, there was no change in the dissociation constant during gestation. After injecting betamethasone (0.17 mg/kg, 24 hours) into rabbits at 25 days of pregnancy, we found that the concentration of pulmonary beta-receptors increased from 44.2 +/- 6.6 fmol/mg protein in untreated fetuses to 77.9 +/- 5.6 fmol/mg protein in treated fetuses. However, this treatment did not affect the DHA binding sites in the fetal rabbit heart. Maternal treatment with the T3 analogue 3,5-dimethyl-3'-isopropyl-L-thyronine (0.5-1 mg/kg) at a dosage which increased both surfactant synthesis and release did not alter pulmonary receptor concentration. Our results indicate that the concentration of pulmonary beta-adrenergic receptors increases in the fetus at term and suggest that this increase is stimulated by endogenous glucocorticoid in fetal circulation.


Assuntos
Betametasona/farmacologia , Pulmão/embriologia , Receptores Adrenérgicos beta/efeitos dos fármacos , Receptores Adrenérgicos/efeitos dos fármacos , Animais , Di-Hidroalprenolol/metabolismo , Feminino , Idade Gestacional , Pulmão/metabolismo , Gravidez , Coelhos , Receptores Adrenérgicos beta/metabolismo
9.
J Med Chem ; 39(1): 120-5, 1996 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-8568798

RESUMO

In addition to having desirable inhibitory effects on inflammation, anaphylaxis, and smooth muscle contraction, PDE-IV inhibitors also produce undesirable side effects including nausea and vomiting. In general, compounds that inhibit PDE-IV also potently displace [3H]rolipram from a high-affinity binding site in rat cortex. While this binding site has not been identified, it has been proposed to be an allosteric binding site on the PDE-IV enzyme. Preliminary studies have suggested that the emetic potency of PDE-IV inhibitors is correlated with affinity for the brain rolipram binding site rather than potency at inhibiting PDE-IV enzyme activity. Efforts to eliminate the emetic potential of PDE-IV inhibitors were directed toward developing compounds with decreased [3H]rolipram binding affinity while retaining PDE-IV potency. Thus, a novel series of 4-(3-alkoxy-4-methoxyphenyl)benzoic acids and their corresponding carboxamides were prepared and evaluated for their PDE-IV inhibitory and rolipram binding site properties. Modification of the catechol ether moiety led to phenylbutoxy and phenylpentoxy analogues that provided the desired activity profile. Specifically, 4-[3-(5-phenylpentoxy)-4-methoxyphenyl]-2-methylbenzoic acid, 18, was found to exhibit potent PDE-IV inhibitory activity (IC50 0.41 microM) and possessed 400 times weaker activity than rolipram for the [3H]rolipram binding site. In vivo, compound 18 was efficacious in the guinea pig aerosolized antigen induced airway obstruction assay (ED50 8.8 mg/kg, po) and demonstrated a significant reduction in emetic side effects (ferret, 20% emesis at 30 mg/kg, po).


Assuntos
3',5'-AMP Cíclico Fosfodiesterases , Benzoatos , Benzoatos/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Diester Fosfórico Hidrolases/metabolismo , Pirrolidinonas/metabolismo , Animais , Benzoatos/síntese química , Benzoatos/química , Benzoatos/metabolismo , Sítios de Ligação , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Furões , Cobaias , Humanos , Camundongos , Inibidores de Fosfodiesterase/síntese química , Inibidores de Fosfodiesterase/química , Inibidores de Fosfodiesterase/metabolismo , Rolipram , Relação Estrutura-Atividade , Vômito/induzido quimicamente
10.
J Med Chem ; 41(13): 2268-77, 1998 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-9632360

RESUMO

High-throughput file screening against inhibition of human lung PDE4 led to the discovery of 3-ethyl-1-(4-fluorophenyl)-6-phenyl-7-oxo-4, 5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine (11) as a novel PDE4 inhibitor. Subsequent SAR development, using an eosinophil PDE assay, led to analogues up to 50-fold more potent than 11 with IC50 values of 0.03-1.6 microM. One such compound, CP-220,629 (22) (IC50 = 0.44 microM), was efficacious in the guinea pig aerosolized antigen induced airway obstruction assay (ED50 2.0 mg/kg, po) and demonstrated a significant reduction in eosinophil (55%), neutrophil (65%), and IL-1beta (82%) responses to antigen challenge in atopic monkeys (10 mg/kg, po).


Assuntos
Antiasmáticos , Anti-Inflamatórios não Esteroides , Di-Hidropiridinas , Eosinófilos/enzimologia , Isoenzimas/antagonistas & inibidores , Inibidores de Fosfodiesterase , Diester Fosfórico Hidrolases/metabolismo , Pirazóis , Obstrução das Vias Respiratórias/imunologia , Obstrução das Vias Respiratórias/metabolismo , Obstrução das Vias Respiratórias/patologia , Obstrução das Vias Respiratórias/prevenção & controle , Animais , Antiasmáticos/síntese química , Antiasmáticos/química , Antiasmáticos/farmacologia , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Contagem de Células/efeitos dos fármacos , Linhagem Celular , AMP Cíclico/metabolismo , Citocinas/metabolismo , Di-Hidropiridinas/síntese química , Di-Hidropiridinas/química , Di-Hidropiridinas/farmacologia , Avaliação Pré-Clínica de Medicamentos , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia , Cobaias , Humanos , Técnicas In Vitro , Macaca fascicularis , Conformação Molecular , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Ovalbumina/imunologia , Inibidores de Fosfodiesterase/síntese química , Inibidores de Fosfodiesterase/química , Inibidores de Fosfodiesterase/farmacologia , Pirazóis/síntese química , Pirazóis/química , Pirazóis/farmacologia , Pirrolidinonas/farmacologia , Rolipram , Relação Estrutura-Atividade
11.
Br J Pharmacol ; 70(4): 515-7, 1980 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6258677

RESUMO

Using [3H]-dihydroergocryptine, we identified myocardial alpha-adrenoceptor binding sites in foetal lambs and demonstrated that the concentration of receptors decreased with increasing foetal age. The presence of the receptor in the foetus correlated with the presence of myocardial alpha-adrenergic responsiveness. However, we found neither the alpha-receptor binding site nor responsiveness to alpha-adrenoceptor stimulation in the myocardium of adult sheep.


Assuntos
Coração Fetal/análise , Receptores Adrenérgicos alfa/análise , Receptores Adrenérgicos/análise , Animais , Sítios de Ligação , Feminino , Idade Gestacional , Contração Miocárdica/efeitos dos fármacos , Gravidez , Receptores Adrenérgicos beta/análise , Ovinos
12.
Br J Pharmacol ; 128(3): 788-94, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10516663

RESUMO

1. The ability of various C-C chemokines to elicit tissue eosinophil infiltration following intradermal injection or peripheral blood eosinophilia following intravenous injection were compared in the Brown-Norway rat. 2. Eotaxin (0.1 - 3 microg site-1) of human and murine origin produced equivalent, dose-dependent increases in eosinophil peroxidase activity in rat dermis 4 h post-injection. 3. Human eotaxin-2 was equipotent with human eotaxin in terms of dermal eosinophil recruitment. Other human CCR3 agonists, such as MCP-3, RANTES and MCP-4 failed to increase dermal eosinophil peroxidase activity at doses up to 1 microg site-1 whereas the latter did produce a small effect at 3 microg site-1. 4. Consistent with observations in vivo, human eotaxin displaced [125I]-eotaxin from rat spleen membranes more potently (IC50=2 nM) than did MCP-4 (IC50=500 nM). RANTES did not compete with the radiolabelled chemokine at concentrations up to 1 microM. 5. Human eotaxin (5 microg) administered intravenously increased circulating eosinophils approximately 3 fold whereas MCP-4 (5 microg i.v.) increased circulating monocytes approximately 3 fold without affecting eosinophil numbers. 6. Dexamethasone pretreatment inhibited eotaxin-induced dermal eosinophil influx only at a steroid dose (0.1 mg kg-1, s.c.) which significantly reduced circulating eosinophil numbers. The steroid also reduced eosinophilia in peripheral blood resulting from systemic eotaxin administration (5 microg, i.v.). 7. These data suggest differences in rat CCR3 relative to other species as surmised from a distinctive rank order of chemokine potency. In addition to its chemotactic effects eotaxin, but not MCP-4, promotes eosinophil recruitment into the circulation. One of the mechanisms by which glucocorticoids, such as dexamethasone, acutely inhibits eotaxin-induced dermal eosinophil influx is to diminish the circulating numbers of these cells available for tissue recruitment.


Assuntos
Quimiocinas CC , Eosinófilos/efeitos dos fármacos , Receptores de Quimiocinas/agonistas , Receptores de HIV/agonistas , Animais , Anti-Inflamatórios/farmacologia , Agregação Celular/efeitos dos fármacos , Quimiocina CCL11 , Quimiocinas/farmacologia , Citocinas/farmacologia , Dexametasona/farmacologia , Eosinófilos/citologia , Leucócitos/citologia , Leucócitos/efeitos dos fármacos , Ratos , Receptores CCR3
13.
Br J Pharmacol ; 117(7): 1530-4, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8730750

RESUMO

1. The role of adrenal hormones in the regulation of the systemic and local production of tumour necrosis factor (TNF alpha) was examined in male Balb/c mice. 2. Intraperitoneal injection of 0.3 mg E. coli lipopolysaccharide (LPS, 0111:B4) led to high levels of circulating TNF alpha without stimulating TNF alpha production in the peritoneal cavity. Systemic production of TNF alpha in response to LPS was increased in adrenalectomized animals and in normal animals treated with the beta-adrenoceptor antagonist, propranolol. The glucocorticoid antagonist, RU 486, did not modify systemic TNF alpha production. These results indicate that systemic TNF alpha production is regulated by adrenaline but not by corticosterone. 3. When mice were primed with thioglycollate, TNF alpha was produced in the peritoneal cavity in response to low dose LPS (1 micrograms). The levels of TNF alpha in the peritoneal cavity were not enhanced by adrenalectomy or by treatment with either propranolol or RU 486, indicating local production of TNF alpha in the peritoneal cavity is not regulated by adrenaline or corticosterone. 4. The phosphodiesterase type IV (PDE-IV) inhibitor, rolipram, inhibited both the systemic production of TNF alpha in response to high dose endotoxin (ED50 = 1.3 mg kg-1) and the local production of TNF alpha in the peritoneal cavity in response to low dose endotoxin (ED50 = 9.1 mg kg-1). In adrenalectomized mice there was a slight reduction in the ability of rolipram to inhibit the systemic production of TNF alpha (ED50 = 3.3 mg kg-1) while the ability of rolipram to inhibit the local production of TNF alpha in the peritoneal cavity was virtually abolished (24% inhibition at 30 mg kg-1). The glucocorticoid antagonist, RU 486, also reduced the ability of rolipram to inhibit local TNF alpha production while propranolol was without effect. 5. Systemic treatment with rolipram increased the plasma concentrations of corticosterone in normal mice but not in adrenalectomized mice indicating that rolipram can cause adrenal stimulation in vivo. 6. In summary, these data indicate that systemic production of TNF alpha in response to high dose endotoxin is controlled differently from the local production of TNF alpha in response to low dose endotoxin. The systemic production of TNF alpha is regulated by catecholamines, but not by corticosterone, while the local production of TNF alpha in the peritoneal cavity is not regulated by basal levels of either catecholamines or corticosterone. 7. These data also show that the ability of rolipram to inhibit the local production of TNF alpha is dependent on the release of corticosterone from the adrenal glands.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Pirrolidinonas/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Adrenalectomia , Animais , Corticosterona/sangue , Escherichia coli , Lipopolissacarídeos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mifepristona/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Propranolol/farmacologia , Rolipram , Fator de Necrose Tumoral alfa/antagonistas & inibidores
14.
Eur J Pharmacol ; 88(2-3): 269-72, 1983 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-6852113

RESUMO

Using [3H]QNB, we demonstrated that GTP and Gpp(NH)p increased muscarinic receptor high affinity sites in bovine tracheal muscle preparations; however, neither the dissociation constant of [3H]QNB binding sites nor pulmonary beta-adrenergic receptor sites was altered. The GTP effect on increasing the receptor sites was relatively small (16%), sensitive (ED50 0.48 microM) and specific (Gpp(NH)p greater than GTP = GDP greater than GMP much greater than ATP). Mg2+ potentiated this increase by up to 94.8%, whereas Na+, K+ and Ca2+ had no such effect.


Assuntos
Guanosina Trifosfato/farmacologia , Magnésio/fisiologia , Receptores Colinérgicos/efeitos dos fármacos , Receptores Muscarínicos/efeitos dos fármacos , Animais , Bovinos , Guanilil Imidodifosfato/farmacologia , Técnicas In Vitro , Membranas/metabolismo , Músculo Liso/efeitos dos fármacos , Parassimpatolíticos/metabolismo , Quinuclidinil Benzilato/metabolismo , Receptores Muscarínicos/metabolismo , Traqueia/metabolismo
15.
Life Sci ; 30(24): 2079-86, 1982 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-6287140

RESUMO

This study was undertaken to compare the activity of muscarinic and beta adrenergic receptors in bovine peripheral lung to the corresponding receptor activity in tracheal smooth muscle. We used [3H] quinuclidinyl benzilate (QNB) and [3H]dihydroalprenolol (DHA) to measure muscarinic and beta receptor activity, respectively. Binding to QNB and DHA at 25 degrees C was rapid, reversible, saturable and of high affinity. The order of potency for cholinergic and adrenergic agents competing for binding was compatible with muscarinic and beta 2 adrenergic potencies. We found that the concentration of muscarinic receptor binding sites was 37-fold greater in the tracheal muscle preparation (2805 +/- 309 fmol/mg protein) than in the peripheral lung preparation (76 +/- 28 fmol/mg protein). Unlike muscarinic receptors, the lung contained 8-fold higher concentration of the beta adrenergic receptors than did the tracheal muscle (1588 +/- 417 vs. 199 +/- 42 fmol/mg protein). The dissociation constant or the agonist's inhibitory constant (Ki) for either receptor binding site, however, was not significantly different between the two tissues. Furthermore, in vitro contraction studies showed that the response of tracheal muscle strips to methacholine was markedly greater than the response of peripheral lung strips, a finding consistent with the QNB binding result. The muscle but not the peripheral lung strip exhibited a relaxing response to epinephrine. Our data indicate a striking quantitative difference in muscarinic and beta adrenergic receptors between lung tissue and tracheal muscle, and that each receptor in the lung is qualitatively similar to the corresponding receptor in the muscle.


Assuntos
Pulmão/metabolismo , Músculo Liso/metabolismo , Receptores Adrenérgicos beta/metabolismo , Receptores Adrenérgicos/metabolismo , Receptores Colinérgicos/metabolismo , Receptores Muscarínicos/metabolismo , Traqueia/metabolismo , Animais , Bovinos , Epinefrina/farmacologia , Técnicas In Vitro , Cloreto de Metacolina , Compostos de Metacolina/farmacologia , Contração Muscular/efeitos dos fármacos
16.
Life Sci ; 42(22): 2241-8, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2836680

RESUMO

To establish a simple and sensitive quantitation of leukotriene B4 (LTB4), we developed a radioreceptor assay (RRA) using a highly specific [3H]leukotriene B4[( 3H]LTB4) binding to a guinea pig spleen homogenate. The assay detected LTB4 levels as low as 0.12 pmol per tube. Fifty percent inhibition of bound [3H]LTB4 was obtained by 2.5 nM of unlabeled LTB4. [3H]LTB4 competition studies indicated that 20-hydroxy-LTB4 was 8 times, 6-trans-LTB4 was 640 times and 20-carboxy-LTB4 was 1000 times less effective than LTB4. The peptide leukotrienes C4, D4 and E4 showed no effect on [3H]LTB4 binding. Recovery rates averaged 97% after ethanol extraction and evaporation of known amounts of LTB4. The intra-assay coefficients of variation for three samples were 2.4%, 7.2% and 8.4%, respectively. This assay was validated by measuring LTB4 released from human granulocytes stimulated with calcium ionophore A23187. The LTB4 level was maximal at 10 min (156.8 +/- 36.2 pmol/3 x 10(6) cells) and decreased rapidly after 15 min. This radioreceptor assay for leukotriene B4 is highly sensitive and is comparable to the reported sensitivity by radioimmunoassay. The method is simpler and less expensive than other methods such as high pressure liquid chromatography and is suitable for routine measurement of leukotriene B4.


Assuntos
Leucotrieno B4/análise , Ensaio Radioligante , Animais , Ligação Competitiva , Calcimicina/farmacologia , Feminino , Granulócitos/efeitos dos fármacos , Granulócitos/metabolismo , Cobaias , Humanos , Cinética , Leucotrieno B4/metabolismo , Radioimunoensaio , Baço/metabolismo , Trítio
17.
Pediatr Pulmonol ; 1(3 Suppl): S69-76, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2999687

RESUMO

At least two developmental responses necessary to prepare the fetal lung to serve as a gas-exchange organ, the release of surface-active material and the reabsorption of alveolar water, can be stimulated by beta-adrenergic agonists. The sensitivity of these responses increases dramatically in late gestation. beta-Adrenergic receptors can be identified by radioligand binding and are present in human fetal lung as early as 16 weeks of gestation. The temporal relationship of the increases in both pulmonary beta-receptors and plasma-free cortisol in the fetal rabbit during gestation suggests that endogenous glucocorticoids may cause increased concentration of pulmonary beta-receptors. Treatment of pregnant rabbits at 24 or 25 days of gestation results in precocious increases in both fetal lung beta-receptors and agonist-specific, high-affinity binding. The increase in receptor concentration with glucocorticoid is not dependent on other endocrine response inasmuch as 0.1 microM dexamethasone increases beta-receptor concentrations at 24 and 48 hours of incubation in cultures of fetal rabbit lung organ. This effect of glucocorticoid to increase beta-receptor concentration and high-affinity binding may explain the increased fetal pulmonary beta-adrenergic response at term and may be responsible in part for the reduction in neonatal respiratory syndrome seen after antenatal glucocorticoid therapy.


Assuntos
Pulmão/análise , Receptores Adrenérgicos beta/análise , Adenilil Ciclases/metabolismo , Animais , Água Corporal/metabolismo , AMP Cíclico/metabolismo , Dexametasona/farmacologia , Di-Hidroalprenolol/metabolismo , Idade Gestacional , Humanos , Técnicas In Vitro , Isoproterenol/farmacologia , Surfactantes Pulmonares/metabolismo , Ensaio Radioligante , Receptores Adrenérgicos beta/efeitos dos fármacos , Receptores Adrenérgicos beta/metabolismo
18.
Food Chem ; 146: 242-9, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24176338

RESUMO

In this study, a sensitive and rapid method has been developed for the simultaneous determination of aflatoxin M1, ochratoxin A, zearalenone and α-zearalenol in milk by ultra high performance liquid chromatography combined with electrospray ionisation triple quadrupole tandem mass spectrometry (UHPLC-ESI-MS/MS). The milk samples were purified using Oasis HLB cartridge. The matrix effects were evaluated by determining the signal suppression-enhancement (SSE) and corrected by external matrix-matched calibration. The limits of quantity (LOQ) of the mycotoxins were in the range of 0.003-0.015µgkg(-1). The high correlation coefficients (R(2)⩾0.996) were obtained in the range of 0.01-1.00µgkg(-1) of the mycotoxins, along with good recovery (87.0-109%), repeatability (3.4-9.9%) and intra-laboratory reproducibility (4.0-9.9%) at the concentrations of 0.025, 0.1 and 0.5µgkg(-1). The detected rates of the mycotoxins were from 16.7% to 96.7% in raw milk, liquid milk and milk powder samples collected from the dairy farms and supermarkets in Beijing. The method proposed is suitable for the simultaneous determination of aflatoxin M1, ochratoxin A, zearalenone, and α-zearalenol, and could be performed for analysing the mycotoxins in milk.


Assuntos
Aflatoxina M1/análise , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Leite/química , Ocratoxinas/análise , Espectrometria de Massas em Tandem/métodos , Zearalenona/análise , Zeranol/análogos & derivados , Animais , Bovinos , Zeranol/análise
19.
Clin Pharmacol Ther ; 89(6): 821-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21451504

RESUMO

Hepatitis C virus (HCV) infection is an issue of global concern, and studies are ongoing to identify new therapies that are both effective and safe. PF-4878691 is a Toll-like receptor 7 (TLR7) agonist modeled so as to dissociate its antiviral activities from its inflammatory activities. In a proof-of-mechanism study in healthy volunteers who received doses of 3, 6, and 9 mg of PF-4878691 twice a week for 2 weeks, PF-4878691 induced biomarkers of the immune and interferon (IFN) responses in a dose-dependent and dose-frequency-related manner. A novel finding was induction of TLR7 expression in vivo in response to PF-4878691, leading to an amplified biomarker response. A nonresponder at the 9-mg dose had a polymorphism in the IFN-α receptor 1 subunit (Val168Leu). Two subjects who had received 9-mg doses experienced serious adverse events (SAEs), characterized by flu-like symptoms, hypotension, and lymphopenia, leading to early termination of the study. TLR7 stimulation results in a pharmacologic response at levels commensurate with predicted antiviral efficacy, but these doses are associated with SAEs, raising concerns about the therapeutic window of this class of compounds for the treatment of HCV infection.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepacivirus/imunologia , Imunidade Inata/efeitos dos fármacos , Receptor 7 Toll-Like/agonistas , Receptor 7 Toll-Like/imunologia , Adulto , Estudos de Coortes , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptor 7 Toll-Like/biossíntese , Resultado do Tratamento , Adulto Jovem
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