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1.
Clin Exp Allergy ; 44(11): 1371-85, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25200415

RESUMO

BACKGROUND: Using a monoclonal antibody with greater affinity for IgE than omalizumab, we examined whether more complete suppression of IgE provided greater pharmacodynamic effects, including suppression of skin prick responses to allergen. OBJECTIVE: To explore the pharmacokinetics, pharmacodynamics and safety of QGE031 (ligelizumab), a novel high-affinity humanized monoclonal IgG1κ anti-IgE. METHODS: Preclinical assessments and two randomized, placebo-controlled, double-blind clinical trials were conducted in atopic subjects. The first trial administered single doses of QGE031 (0.1-10 mg/kg) or placebo intravenously, while the second trial administered two to four doses of QGE031 (0.2- 4 mg/kg) or placebo subcutaneously at 2-week intervals. Both trials included an open-label omalizumab arm. RESULTS: Sixty of 73 (82%) and 96 of 110 (87%) subjects completed the intravenous and subcutaneous studies, respectively. Exposure to QGE031 and its half-life depended on the QGE031 dose and serum IgE level. QGE031 had a biexponential pharmacokinetic profile after intravenous administration and a terminal half-life of approximately 20 days. QGE031 demonstrated dose- and time-dependent suppression of free IgE, basophil FcεRI and basophil surface IgE superior in extent (free IgE and surface IgE) and duration to omalizumab. At Day 85, 6 weeks after the last dose, skin prick wheal responses to allergen were suppressed by > 95% and 41% in subjects treated subcutaneously with QGE031 (2 mg/kg) or omalizumab, respectively (P < 0.001). Urticaria was observed in QGE031- and placebo-treated subjects and was accompanied by systemic symptoms in one subject treated with 10 mg/kg intravenous QGE031. There were no serious adverse events. CONCLUSION AND CLINICAL RELEVANCE: These first clinical data for QGE031, a high-affinity IgG1κ anti-IgE, demonstrate that increased suppression of free IgE compared with omalizumab translated to superior pharmacodynamic effects in atopic subjects, including those with high IgE levels. QGE031 may therefore benefit patients unable to receive, or suboptimally treated with, omalizumab.


Assuntos
Antialérgicos/farmacologia , Antialérgicos/uso terapêutico , Anticorpos Anti-Idiotípicos/farmacologia , Anticorpos Anti-Idiotípicos/uso terapêutico , Hipersensibilidade Imediata/tratamento farmacológico , Hipersensibilidade Imediata/imunologia , Imunoglobulina E/imunologia , Adolescente , Adulto , Anticorpos Monoclonais Humanizados , Afinidade de Anticorpos/imunologia , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Hipersensibilidade Imediata/diagnóstico , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Testes Cutâneos , Resultado do Tratamento , Adulto Jovem
2.
Br J Pharmacol ; 167(5): 1035-47, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22646698

RESUMO

BACKGROUND AND PURPOSE: BAF312 is a next-generation sphingosine 1-phosphate (S1P) receptor modulator, selective for S1P(1) and S1P(5 ) receptors. S1P(1) receptors are essential for lymphocyte egress from lymph nodes and a drug target in immune-mediated diseases. Here, we have characterized the immunomodulatory potential of BAF312 and the S1P receptor-mediated effects on heart rate using preclinical and human data. EXPERIMENTAL APPROACH: BAF312 was tested in a rat experimental autoimmune encephalomyelitis (EAE) model. Electrophysiological recordings of G-protein-coupled inwardly rectifying potassium (GIRK) channels were carried out in human atrial myocytes. A Phase I multiple-dose trial studied the pharmacokinetics, pharmacodynamics and safety of BAF312 in 48 healthy subjects. KEY RESULTS: BAF312 effectively suppressed EAE in rats by internalizing S1P(1) receptors, rendering them insensitive to the egress signal from lymph nodes. In healthy volunteers, BAF312 caused preferential decreases in CD4(+) T cells, T(naïve) , T(central memory) and B cells within 4-6 h. Cell counts returned to normal ranges within a week after stopping treatment, in line with the elimination half-life of BAF312. Despite sparing S1P(3) receptors (associated with bradycardia in mice), BAF312 induced rapid, transient (day 1 only) bradycardia in humans. BAF312-mediated activation of GIRK channels in human atrial myocytes can fully explain the bradycardia. CONCLUSION AND IMPLICATIONS: This study illustrates species-specific differences in S1P receptor specificity for first-dose cardiac effects. Based on its profound but rapidly reversible inhibition of lymphocyte trafficking, BAF312 may have potential as a treatment for immune-mediated diseases.


Assuntos
Frequência Cardíaca/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Linfócitos/efeitos dos fármacos , Receptores de Lisoesfingolipídeo/fisiologia , Adolescente , Adulto , Animais , Azetidinas/farmacologia , Azetidinas/uso terapêutico , Compostos de Benzil/farmacologia , Compostos de Benzil/uso terapêutico , Células CHO , Cricetinae , Cricetulus , Método Duplo-Cego , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/fisiopatologia , Feminino , Humanos , Fatores Imunológicos/uso terapêutico , Contagem de Linfócitos , Linfócitos/fisiologia , Masculino , Pessoa de Meia-Idade , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/fisiologia , Ratos , Especificidade da Espécie , Adulto Jovem
4.
Neth Heart J ; 13(7-8): 269-273, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25696507

RESUMO

BACKGROUND: Atrial fibrillation (AF), the most common cardiac arrhythmia, is characterised by rapid and irregular contraction of the atrium. The risk of AF increases with age and AF increases the risk of various heart disorders, stroke and mortality. AF can occur in a sporadic or familial form. The underlying mechanism leading to AF is not well known but genetic analysis can increase our insight into the molecular pathways in AF. Detailed information on the molecular mechanisms of a disorder increase options for diagnosis and treatment. Recently, a gain-of-function mutation in exon of the KCNQ1 gene located on chromosome 11 was identified in a large Chinese AF family. KCNQ1 associates with KCNE1 or KCNE2 (both located on chromosome 21) to form cardiac potassium channels. Subsequent analysis of Chinese families showed a KCNE2 mutation in two families. Other genetic studies show linkage to chromosome 6 and 10, indicating genetic heterogeneity. A number of studies have shown that altered expression of the atrial connexin40 protein is a risk factor for AF. Connexin genes encode gap-junction proteins that are important in cardiac conduction and for normal wave propagation. OBJECTIVES/METHODS: In this study we analysed the role of KCNQ1, KCNE1 coding region and Cx40 promoter region in six Dutch AF families by sequence analysis. CONCLUSION: No mutations were found in these genes. The absence of mutations indicates genetic heterogeneity in familial AF; however, further research is needed. Candidate genes are being sequenced, linkage analysis in a large family will be performed and additional AF families will be collected.

5.
J Urol ; 166(6): 2456-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11696811

RESUMO

PURPOSE: We evaluated the combination of alarm and desmopressin versus alarm monotherapy for the treatment of nocturnal enuresis. MATERIALS AND METHODS: A double-blind, placebo controlled study of alarm therapy combined with desmopressin for children with nocturnal enuresis is described. Of 93 patients 47 were randomized to receive alarm therapy and 40 microg. intranasal desmopressin for 3 weeks followed by 20 microg. desmopressin for 3 weeks (group 1) and 46 received alarm therapy and placebo (group 2). After 6 weeks on alarm therapy and medication or placebo, both groups received an additional 3 weeks of alarm monotherapy. A specialized nurse practitioner advised patients and families of the treatment to be given at home and in the outpatient department. Bed-wetting frequency was evaluated before during and 2 weeks and 6 months after treatment. RESULTS: A significantly greater reduction in the number of wet nights was observed after the first 3 weeks of treatment in group 1. However, after long-term followup no significant differences in bed-wetting frequency were noted. CONCLUSIONS: There is a temporary, positive effect on enuresis using desmopressin combined with alarm therapy. However, both treatment modalities have a low long-term success rate of 36% to 37%.


Assuntos
Desamino Arginina Vasopressina/uso terapêutico , Enurese/terapia , Fármacos Renais/uso terapêutico , Adolescente , Criança , Terapia Combinada , Método Duplo-Cego , Feminino , Humanos , Masculino , Estudos Prospectivos
6.
Biochemistry ; 38(19): 5982-94, 1999 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-10320324

RESUMO

The backbone dynamics of Fusarium solani pisi cutinase in complex with a phosphonate inhibitor has been studied by a variety of nuclear magnetic resonance experiments to probe internal motions on different time scales. The results have been compared with dynamical studies performed on free cutinase. In solution, the enzyme adopts its active conformation only upon binding the inhibitor. While the active site Ser120 is rigidly attached to the stable alpha/beta core of the protein, the remainder of the binding site is very flexible in the free enzyme. The other two active site residues Asp175 and His188 as well as the oxyanion hole residues Ser42 and Gln121 are only restrained into their proper positions upon binding of the substrate-like inhibitor. The flap helix, which opens and closes the binding site in the free molecule, is also fixed in the cutinase-inhibitor complex. Our results are in contrast with the X-ray analysis results, namely that in the protein crystal, free cutinase has a well-defined active site and a preformed oxyanion hole and that it does not need any rearrangements to bind its substrate. Our solution studies show that cutinase does need conformational rearrangements to bind its substrate, which may form the rate-limiting step in catalysis.


Assuntos
Hidrolases de Éster Carboxílico/química , Inibidores Enzimáticos/química , Fusarium/enzimologia , Organofosfonatos/química , Inibidores Enzimáticos/metabolismo , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Organofosfonatos/metabolismo , Conformação Proteica
7.
Biochemistry ; 38(17): 5315-27, 1999 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-10220318

RESUMO

The backbone dynamics of Fusarium solani pisi cutinase has been studied by a variety of nuclear magnetic resonance experiments to probe internal motions on different time scales. The core of cutinase appears to be highly rigid. The binding site, including the oxyanion hole, is mobile on the microsecond to millisecond time scale, in contrast to the well-defined active site and preformed oxyanion hole elucidated by X-ray crystallography [Martinez, C., de Geus, P., Lauwereys, M., Matthyssens, G., and Cambillau, C. (1992) Nature 356, 615-618]. In this crystal structure, cutinase has a rather open conformation, in which the hydrophobic binding site is exposed. The observed mobility in solution most likely represents the interconversion between open and more closed conformations, like in a true lipase. The opening and closing motions are on a time scale which corresponds with the kinetics of the hydrolysis reaction, i.e., the millisecond range, which suggests that these conformational rearrangements form the rate-limiting step in catalysis. We conclude that the crystal structure probably represents one of the multiple conformations present in solution, which fortuitously is the active conformation. The implications of our findings are discussed with particular reference to the explanation of the lack of interfacial activation as found for cutinase.


Assuntos
Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/metabolismo , Fusarium/enzimologia , Sítios de Ligação , Ativação Enzimática , Concentração de Íons de Hidrogênio , Modelos Moleculares , Isótopos de Nitrogênio , Ressonância Magnética Nuclear Biomolecular/métodos , Fragmentos de Peptídeos/química , Ligação Proteica , Conformação Proteica , Sinais Direcionadores de Proteínas/química , Estrutura Secundária de Proteína , Temperatura , Titulometria
8.
Am J Med Genet ; 76(1): 79-86, 1998 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-9508071

RESUMO

Familial hypobetalipoproteinemia (FHBL) is an autosomal dominant disorder of lipid metabolism characterized by extremely low plasma levels of apolipoprotein B (apoB), and total-, and low-density lipoprotein (LDL) cholesterol. Various truncated forms of apoB have been found to cosegregate with the FHBL phenotype in more than 30 kindreds. By contrast, no truncated forms of apoB protein were detected with sensitive immunoblotting in the plasmas of any of the 6 kindreds reported here. Individuals with apoB levels in the 5th centile for their age and sex were considered as affected with FHBL. Linkage analysis was performed using 3 microsatellite markers flanking the apoB gene (D2S131, D2S149, and D2S144), a 3' variable number of tandem repeats (VNTR) marker and one intragenic marker. Two-point linkage of FHBL was established to the 3' VNTR marker with a combined maximum LOD score of 8.5 at theta = 0 for 5 of the 6 families. Maximum LOD scores for flanking microsatellite markers were 5.0, 2.4, 1.3, 1.2 and 2.1 for these kindreds (D, T, De, C and Z, respectively). A test of homogeneity differentiated the 6th family (F kindred) from the other five. LOD scores of -25.2 at the 3' VNTR and -7.8 at the intragenic apoB/Xbal marker at theta = 0 excluded linkage to the apoB gene in the F kindred. These kindreds demonstrate the heterogeneity of FHBL and also offer the possibility to investigate as yet undescribed mutations of apoB, resulting in alterations of apoB metabolism. The F kindred may shed light on novel gene(s) contributing to the low apoB-phenotype.


Assuntos
Apolipoproteínas B/genética , Ligação Genética , Hipobetalipoproteinemias/genética , Apolipoproteínas B/sangue , DNA/genética , Feminino , Genes Dominantes , Marcadores Genéticos , Genótipo , Haplótipos , Humanos , Hipobetalipoproteinemias/sangue , Escore Lod , Masculino , Mutação , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , População Branca/genética
9.
J Magn Reson ; 130(1): 68-75, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9469899

RESUMO

As aromatic residues very often are part of the hydrophobic core of proteins, the unambiguous assignment of the aromatic proton resonances is essential for an accurate and precise structure determination. Instead of transferring 1Hbeta coherence to the aromatic protons via 13Cgamma like in a number of published methods, in our new experiments the 13Cgamma resonances are first correlated with the 1Hbeta chemical shifts in one experiment and then with the aromatic proton resonances in four other experiments. Their short coherence transfer pathways make the experiments applicable to proteins with a molecular weight larger than 20 kDa, as is demonstrated for Fusarium solani pisi cutinase (214 residues). The dispersion of the Cgamma chemical shifts between different aromatic residue types is obvious, but even the dispersion within one type is sufficient to combine the experiments using only the Cgamma chemical shift and to assign nearly all aromatic proton resonances of cutinase. Copyright 1998 Academic Press. Copyright 1998 Academic Press

10.
Protein Sci ; 6(11): 2375-84, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9385640

RESUMO

Essentially complete (96%) sequence-specific assignments were made for the backbone and side-chain 1H, 13C, and 15N resonances of Fusarium solani pisi cutinase, produced as a 214-residue heterologous protein in Escherichia coli, using heteronuclear NMR techniques. Three structural features were noticed during the assignment. (1) The secondary structure in solution corresponds mostly with the structure from X-ray diffraction, suggesting that both structures are globally similar. (2) The HN of Ala32 has a strongly upfield-shifted resonance at 3.97 ppm, indicative of an amide-aromatic hydrogen bond to the indole ring of Trp69 that stabilizes the N-terminal side of the parallel beta-sheet. (3) The NMR data suggest that the residues constituting the oxyanion hole are quite mobile in the free enzyme in solution, in contrast to the existence of a preformed oxyanion hole as observed in the crystal structure. Apparently, cutinase forms its oxyanion hole upon binding of the substrate like true lipases.


Assuntos
Hidrolases de Éster Carboxílico/química , Fusarium/enzimologia , Estrutura Secundária de Proteína , Sequência de Aminoácidos , Aminoácidos/química , Isótopos de Carbono , Hidrogênio , Modelos Moleculares , Dados de Sequência Molecular , Isótopos de Nitrogênio , Ressonância Magnética Nuclear Biomolecular/métodos , Soluções
11.
Leukemia ; 10(11): 1741-50, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8892677

RESUMO

SDZ PSC 833, a non-immunosuppressive cyclosporin analogue reverses multidrug resistance (MDR) in vitro by inhibiting P-glycoprotein (P-gp) mediated drug efflux. We performed a dose escalation study of SDZ PSC 833 combined with VAD chemotherapy in refractory multiple myeloma (MM). Twenty-two MM patients who were refractory to doxorubicin/vincristine/dexamethasone (VADr, n=11) or had failed multiple regimens (n=6) or were melphalan-refractory (MELr, n=5), were treated with one to three cycles of VAD combined with oral SDZ PSC 833, which was administered at escalating dosages starting at 5 mg/kg/day to 15 mg/kg/day for 7 days. The median trough and peak blood levels of SDZ PSC 833 ranged from 461/1134 ng/ml at 5 mg/kg/day to 821/2663 ng/ml at 15 mg/kg, respectively. With addition of SDZ PSC 833 (5 mg/kg) the mean plasma AUC 0-->96 h of doxorubicin as compared with control patients treated with VAD increased from 779 to 1510 ng/ml/h (P=0.0071), while the doxorubicin clearance was reduced from 47.6 to 27.8 l/h/m2 (P=0.0002). The clearance of doxorubicinol was reduced accordingly. Because of the increased plasma AUC, the dose of doxorubicin and vincristine had to be reduced in 13 patients to 50% (n=1) or 75% (n=12). A further dose-escalation of SDZ PSC 833 did not lead to a proportional increase of doxorubicin AUC. Toxicity WHO CTC grade 2 or 3 included hypoplasia (18/22), constipation (10/22), hyponatremia (3/22) and infections (6/22). A partial response or stable disease was achieved in eight and six patients, respectively. In 17 evaluable patients the mean percentage of pretreatment bone marrow plasma cells which expressed P-glycoprotein was 40%. The pretreatment in vitro rhodamin retention in CD38++ myeloma cells was reversible by 2 microM SDZ PSC 833 with 15-98% in 7/9 tested patients. In 4/5 responding patients analyzed before and after treatment with VAD + SDZ PSC 833, a reduction of P-gp + plasma cells was observed. It is concluded, that the blood concentrations of SDZ PSC 833 attained in MM patients increase with dose after oral administration. It can be safely combined with VAD chemotherapy. SDZ PSC 833 diminishes the clearance of doxorubicin, leading to an increase of the plasma AUC of doxorubicin. In addition, it is an effective inhibitor of P-gp mediated efflux of doxorubicin in myeloma tumor cells in vitro. Therefore, a proportional dose-reduction of doxorubicin and vincristine is warranted. Phase II/III studies in refractory MM are in progress to evaluate the therapeutic efficacy of SDZ PSC 833 with VAD.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ciclosporinas/administração & dosagem , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Mieloma Múltiplo/tratamento farmacológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Administração Oral , Idoso , Estudos de Coortes , Ciclosporinas/efeitos adversos , Ciclosporinas/farmacocinética , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Dexametasona/farmacocinética , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Doxorrubicina/farmacocinética , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/metabolismo , Vincristina/administração & dosagem , Vincristina/efeitos adversos , Vincristina/farmacocinética
12.
Br J Cancer ; 73(6): 789-93, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8611381

RESUMO

A phase II trial investigating the anti-tumour effects of recombinant human interleukin 6 (rhIL-6) in patients with metastatic renal cell cancer was carried out. RhIL-6 (150 microgram) was administered as a daily subcutaneous injection for 42 consecutive days on an outpatient basis. Forty-nine patients were studied, 12 with and 37 without previous immunotherapy. Forty patients were evaluable for response. A partial remission was noted in two patients, stable disease in 17 and progressive disease in 21. Toxicity was moderate and reversible and consisted mainly of fever, flu-like symptoms, nausea, weight loss and hepatotoxicity. Anaemia, leucocytosis and thrombocytosis and induction of acute phase protein synthesis were noted in most patients. In 15% of the patients anti-IL-6 antibodies developed, and were neutralising in only one patient. Baseline plasma IL-6 concentrations did not correlate with tumour behaviour before or after rhIL-6 treatment. In conclusion, rhIL-6 can be safely administered on an outpatient basis for prolonged period of time and has moderate, reversible toxicity. Its administration induces IL-6-antibody production in only a minority of patients. Antitmour effects of rhIL-6 in metastatic renal cancer are limited.


Assuntos
Carcinoma de Células Renais/tratamento farmacológico , Interleucina-6/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Reação de Fase Aguda/induzido quimicamente , Anemia/induzido quimicamente , Carcinoma de Células Renais/sangue , Carcinoma de Células Renais/imunologia , Feminino , Hemoglobinas/efeitos dos fármacos , Hemoglobinas/metabolismo , Humanos , Interleucina-6/efeitos adversos , Interleucina-6/imunologia , Neoplasias Renais/sangue , Neoplasias Renais/imunologia , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/uso terapêutico
13.
Leukemia ; 10(1): 43-7, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8558936

RESUMO

Patients with AML who relapse after an initial remission, have a poor prognosis. Administration of hemopoietic growth factors (HGFs) such as interleukin-3 (IL-3) during chemotherapy may result in an increased cell kill by cytotoxic agents. In addition, administration of IL-3 following chemotherapy may potentially accelerate hemopoietic recovery from chemotherapy-induced bone marrow hypoplasia. We performed an open labelled, phase I/II study in which patients received IL-3 by continuous infusion from 24 h before the beginning of chemotherapy until day 28. Chemotherapy included daunorubicin or mitoxantrone days 1-3 and cytarabine 200 mg/m2 days 1-7. IL-3 was given at a dose of 5 microgram(s)/kg/day in 10 patients, 7.5 microgram(s)/kg /day in six patients and 10 microgram(s)/kg/day in four patients. Complete remissions (CR) after one cycle of this treatment were obtained in 5/10 patients and 5 microgram(s)/ kg group, 2/6 in the 7.5 microgram(s)/kg group and 3/4 in the 10 microgram(s)/kg group). Thus, 50% (10/20) of all individuals and 45% (5/11) of the elderly patients attained CR. Eight of 20 patients entered PR, and 2/20 patients died during the hypoplastic phase from infectious complications. Neutrophils and platelets recovered to 0.5 x 10(9)/l at day 25 (median) and to 50 x 10(9)/l at day 32, respectively. Adverse events during IL-3 and concomitant chemotherapy were fluid retention (4/20), rash (14/20), bone pain (2/20), headache (10/20), chest pain (1/20), arthritis (1/20), fever and nausea. IL-3 (at the dose of 10 microgram(s)/kg) was discontinued in two patients because of side-effects (fluid retention, fever, rash and chest pain), and in two other patients the high IL-3 dose was tolerated with no problems for 29 days. Thus, IL-3 applied to patients with high-risk AML at dosages of 5-10 microgram(s)/kg is tolerated with acceptable toxicity and results in a satisfactory frequency of complete responses following a single treatment cycle.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Interleucina-3/uso terapêutico , Leucemia Mieloide Aguda/terapia , Adulto , Idoso , Antibióticos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/administração & dosagem , Terapia Combinada , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Feminino , Humanos , Interleucina-3/administração & dosagem , Interleucina-3/efeitos adversos , Leucemia Mieloide Aguda/sangue , Leucemia Mieloide Aguda/tratamento farmacológico , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Contagem de Plaquetas , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Recidiva , Indução de Remissão
14.
Anal Biochem ; 230(1): 135-48, 1995 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-8585609

RESUMO

Natural mixtures of sophorolipids produced by the yeast Candida bombicola have been analyzed by fast atom bombardment (FAB)-MS and collision-induced dissociation (CID)-MS. Some pure components have been analysed by two-dimensional NMR spectroscopy. The presence of acidic, lactonic, and O-acetylated forms and the position of double bonds in the fatty acid part of these glycolipids can be easily inferred from positive and negative ion FAB-mass spectra. Details about position of O-acetylation can be obtained from CID mass spectra of [M+H]+ and [M-H]- ions and from the NMR spectra. Differences in CID fragmentation between protonated and sodiated molecular ions are discussed in detail. Enzymatic hydrolysis of 6',6"-di-O-acetyl sophorolipid lactone by cutinase from Fusarium solani results specifically in the removal of the 6'-O-acetyl group, whereas the 6"-O-acetyl and lactone group are resistant. This specificity is explained from a three-dimensional model of the sophorolipid generated on the basis of the short 1H,1H distances as inferred from the NMR (ROESY) spectra.


Assuntos
Candida/metabolismo , Detergentes , Glicolipídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Tensoativos/isolamento & purificação , Ânions , Sequência de Carboidratos , Hidrolases de Éster Carboxílico , Glicolipídeos/biossíntese , Glicolipídeos/química , Hidrólise , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Molecular , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Tensoativos/química
15.
Cytometry ; 19(3): 209-16, 1995 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-7736866

RESUMO

A flow cytometer was developed for the high-speed "sorting" of desired cells by selectively irradiating (zapping) the undesired cells from a population. After previous efforts to photoinactivate cells with photosensitizers had failed, it was decided to exploit the photosensitivity of the cell's DNA at 257 nm. It was shown that a 257 nm laser output power of 20-100 mW was sufficient to induce a 4.5 log cell kill after the cells were processed through a focused 257 nm laser beam. Experiments proved that the photodamage flow cytometer (ZAPPER) could selectively photoinactivate cells at rates over 22,000 events/s, and selection purities ranged from 81% to 100%. The yields of the desired cells depended on the selection mode. In the Enrichment mode, the zap laser was not aimed at the jet, and only undesired cells were exposed to a brief ultraviolet (UV) pulse after modulation of the UV laser beam. The yields of desired cells ranged from 95% to 105%. In the Purge mode, the zap laser beam was aimed onto the jet, and only desired cells were allowed to pass after deflection of the UV laser beam; the yields of desired cells ranged from 12% to 52%. The cause of the reduced yields in the PURGE mode was traced to the fact that the Electro-Optic Modulator was used to modulate the zap laser proved too slow for the intended application. The lifetime of the frequency-doubling crystal used for the generation of the 257 nm beam was found to be limited to several days.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Separação Celular/métodos , Citometria de Fluxo/métodos , Lasers , Animais , Argônio , Separação Celular/instrumentação , Escherichia coli , Citometria de Fluxo/instrumentação , Leucócitos , Raios Ultravioleta
16.
Cancer Chemother Pharmacol ; 36(6): 477-82, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7554039

RESUMO

The administration of platinum-based chemotherapy induces serotonin release from the enterochromaffin cells, causing nausea and vomiting. This study was conducted to evaluate parameters of serotonin metabolism following platinum-based chemotherapy given in combination with the serotonin type-3 antagonist tropisetron as an antiemetic agent. In nine chemotherapy-naive patients with disseminated germ-cell tumors, parameters of serotonin metabolism in both blood and urine were evaluated during two consecutive courses of platinum-based chemotherapy. Serotonin concentrations in platelet-rich plasma and platelet-poor plasma as well as urinary 5-hydroxyindoleacetic acid (5-HIAA) and serotonin levels were measured during the full length of the courses. By means of comparison with the antiemetic agent chlorpromazine, used on day 1 of the first course only, the effect of the serotonin type-3 antagonist tropisetron, the antiemetic agent used during the rest of the courses, on these parameters was studied. Clinical effects were also recorded. No change in the parameters of serotonin metabolism could be demonstrated during either course by the serotonin type-3 antagonist tropisetron. Also in vitro, no effect of tropisetron on the active serotonin uptake by platelets was found. Serotonin levels in platelets showed no correlation with emetic response. However, the platelet serotonin content decreased significantly between the first and the second course (P < 0.01). The significant reduction in platelet serotonin content observed between the first and the second course indicates a depletion of total body serotonin. The role of a serotonin type-3 antagonist might be affected by the altered serotonin equilibrium during later courses of chemotherapy.


Assuntos
Antieméticos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Indóis/uso terapêutico , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Antagonistas da Serotonina/uso terapêutico , Serotonina/metabolismo , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bleomicina/administração & dosagem , Bleomicina/efeitos adversos , Clorpromazina/farmacologia , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Interações Medicamentosas , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Humanos , Ácido Hidroxi-Indolacético/urina , Indóis/farmacologia , Infusões Intravenosas , Neoplasias Embrionárias de Células Germinativas/metabolismo , Serotonina/sangue , Antagonistas da Serotonina/farmacologia , Tropizetrona , Vômito/induzido quimicamente , Vômito/prevenção & controle
17.
Cytometry ; 19(1): 92-6, 1995 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-7705190

RESUMO

A new data acquisition and analysis format (classmode) was developed that allows real-time data classification in a flow cytometer. In our cytometer, detected events were classified in real time by their presence or absence in a set of look-up tables (LUT). A modification of the cytometer hardware allows the exclusive transfer of the LUT data to the acquisition/storage computer. Using a combination of 8 LUTs, the analyzed events can be classified into 256 subpopulations. Real-time data classification results in an increased data transfer rate and a significant compression of the data.


Assuntos
Citometria de Fluxo/instrumentação , Processamento de Sinais Assistido por Computador , Software , Células Cultivadas
18.
J Biomol NMR ; 4(2): 257-78, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8019137

RESUMO

1H, 13C and 15N NMR assignments of the backbone atoms of subtilisin 309, secreted by Bacillus lentus, have been made using heteronuclear 3D NMR techniques. With 269 amino acids, this protein is one of the largest proteins to be sequentially assigned by NMR methods to date. Because of the size of the protein, some useful 3D correlation experiments were too insensitive to be used in the procedure. The HNCO, HN(CO)-CA, HNCA and HCACO experiments are robust enough to provide most of the expected correlations for a protein of this size. It was necessary to use several experiments to unambiguously determine a majority of the alpha-protons. Combined use of HCACO, HN(COCA)HA, HN(CA)HA, 15N TOCSY-HMQC and 15N NOESY-HMQC experiments provided the H alpha chemical shifts. Correlations for glycine protons were absent from most of the spectra. A combination of automated and interactive steps was used in the process, similar to that outlined by Ikura et al. [(1990) J. Am. Chem. Soc., 112, 9020-9022] in the seminal paper on heteronuclear backbone assignment. A major impediment to the linking process was the amount of overlap in the C alpha and H alpha frequencies. Ambiguities resulting from this redundancy were solved primarily by assignment of amino acid type, using C alpha chemical shifts and 'TOCSY ladders'. Ninety-four percent of the backbone resonances are reported for this subtilisin. The secondary structure was analyzed using 3D 15N NOESY-HMQC data and C alpha secondary chemical shifts. Comparison with the X-ray structure [Betzel et al. (1992) J. Mol. Biol., 223, 427-445] shows no major differences.


Assuntos
Bacillus/enzimologia , Conformação Proteica , Estrutura Secundária de Proteína , Serina Endopeptidases/química , Sequência de Aminoácidos , Isótopos de Carbono , Hidrogênio , Espectroscopia de Ressonância Magnética/métodos , Dados de Sequência Molecular , Isótopos de Nitrogênio , Difração de Raios X/métodos
20.
J Urol ; 149(6): 1517-20, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8501801

RESUMO

The results of renal transplantation in boys treated for posterior urethral valves were evaluated and compared with a matched control group. Patient and graft survival was equal in both groups, although serum creatinine levels were slightly higher in the posterior urethral valves group. Postoperative complications, such as urinary tract infections, occurred more frequently in the posterior urethral valves group. Urodynamic evaluation was performed before transplantation in 11 of 20 patients. Adequate treatment of bladder dysfunction, such as poor compliance and/or hyperreflexia, is essential in diminishing the risks of secondary graft damage due to severe bladder dysfunction.


Assuntos
Falência Renal Crônica/cirurgia , Transplante de Rim/fisiologia , Uretra/anormalidades , Criança , Seguimentos , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto/fisiologia , Humanos , Falência Renal Crônica/etiologia , Masculino , Complicações Pós-Operatórias/epidemiologia , Derivação Urinária , Infecções Urinárias/epidemiologia , Urodinâmica/fisiologia
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