Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Eur J Surg Oncol ; 48(1): 89-94, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34148825

RESUMO

BACKGROUND: Incidental discovery of pancreatic cystic neoplasms (PCLs) is a common and steadily increasing occurrence. The aim of this study was to investigate a cohort of patients presenting with incidentally detected PCLs which were not included in a surveillance protocol, and to compare their risk of malignant evolution with that of systematically surveilled lesions. MATERIALS AND METHODS: A population of PCLs which did not receive surveillance over a period >10 years (population A) was selected at the Medical University of Vienna. A group of "low risk" branch duct intraductal papillary mucinous neoplasm ≤15 mm in size upon diagnosis undergoing a regular follow-up of at least 5 years at the University of Verona was selected as control (population B). The incidence of pancreatic cancer (PC), cumulative risk of PC and disease-specific survival were compared. RESULTS: Overall, 376 patients with non-surveilled PCLs were included in study group A and compared to 299 patients in group B. This comparison resulted in similar incidence rates of PC (1.6% vs 1.7%, p = 0.938), a strong similarity in terms of disease-specific mortality rates (1.3% vs 0.3%, p = 0.171) and the 5- and 10-year cumulative risk of PC (≅ 1% and 2%, p = 0.589) and DSS (≅ 100% and 98%, p = 0.050). CONCLUSION: The "price to pay" for a negligence-based policy in the population of non-surveilled PCLs was reasonable, and the incidence of PC was comparable to that reported for a population of low-risk cysts enrolled to a standardized surveillance protocol.


Assuntos
Adenoma/patologia , Carcinoma Ductal Pancreático/patologia , Cisto Pancreático/patologia , Neoplasias Intraductais Pancreáticas/patologia , Neoplasias Pancreáticas/patologia , Idoso , Idoso de 80 Anos ou mais , Carcinoma/epidemiologia , Carcinoma/patologia , Carcinoma Ductal Pancreático/epidemiologia , Progressão da Doença , Feminino , Humanos , Incidência , Achados Incidentais , Masculino , Pessoa de Meia-Idade , Neoplasias Císticas, Mucinosas e Serosas/epidemiologia , Neoplasias Císticas, Mucinosas e Serosas/patologia , Neoplasias Pancreáticas/epidemiologia , Estudos Retrospectivos , Conduta Expectante
2.
Int J Surg ; 79: 131-135, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32413504

RESUMO

BACKGROUND: The impact of major liver resection (LR) on the detoxifying function of the remaining liver tissue as represented by CYP3A activity has yet to be assessed. Therefore, this study evaluates the changes in CYP3A activity between preoperative values and after liver resection. MATERIAL AND METHODS: To determine CYP3A activity, midazolam (MDZ) was used as a marker substance, 3 µg were applied intravenously one day before surgery and on the 3rd day after surgery. Subsequently blood was withdrawn at 0, 0.25, 0.5, 1.0, 1.5, 2.0, 2.5, 3, 4 and 6 h post application of the study drug. Plasma MDZ and 1-OH-MDZ concentration was assessed using a LC-MS/MS method. Volumetric analysis of the resected liver was done by syngo.CT liver analysis software (Siemens Healthineers) using preoperative multidetector computed tomography. RESULTS: N = 13 (8 male/5 female) patients were included in this study and received preoperative evaluation, 11 patients were studied also after liver resection. The mean age was 62 (±15.3) years with a mean BMI of 23.6 ± 4.8 kg/m2. No patient suffered from acute liver dysfunction postoperatively. None of the pharmacokinetic parameters assessed were significantly altered by liver resection. CYP3A activity over time was not significantly reduced by major liver resection. CONCLUSION: This study gives first time data on the impact of major liver resection on CYP3A activity. It was shown that MDZ clearance representing in vivo CYP3A activity is not altered by major liver resection. This suggests no dose adjustment of commonly applied drugs which are CYP3A substrates needs to be carried out.


Assuntos
Citocromo P-450 CYP3A/metabolismo , Hepatectomia , Adulto , Idoso , Estudos Controlados Antes e Depois , Feminino , Humanos , Masculino , Midazolam/sangue , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos
4.
Am J Transplant ; 18(4): 916-926, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28980446

RESUMO

The classical pathway (CP) of complement may contribute to the pathogenesis of antibody-mediated rejection (ABMR). Selective CP blockade may be a promising strategy to counteract rejection. The objective of this first-in-patient phase 1b trial was to evaluate the safety/tolerability and CP-blocking potential of 4 weekly doses (60 mg/kg) of the anti-C1s antibody BIVV009 in complement-mediated disorders. Here we describe the results in a cohort of 10 stable kidney transplant recipients (median of 4.3 years posttransplantation) with late active ABMR and features of CP activation, such as capillary C4d or complement-fixing donor-specific antibodies (DSA). During 7 weeks follow-up, no severe adverse events were reported, and BIVV009 profoundly inhibited overall and DSA-triggered CP activation in serum. Five of 8 C4d-positive recipients turned C4d-negative in 5-week follow-up biopsies, while another 2 recipients showed a substantial decrease in C4d scores. There was, however, no change in microcirculation inflammation, gene expression patterns, DSA levels, or kidney function. In conclusion, we demonstrate that BIVV009 effectively blocks alloantibody-triggered CP activation, even though short-course treatment had no effect on indices of activity in late ABMR. This initial trial provides a valuable basis for future studies designed to clarify the therapeutic value of CP blockade in transplantation. ClinicalTrials.gov NCT#02502903.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Complemento C1s/imunologia , Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto/efeitos dos fármacos , Isoanticorpos/efeitos adversos , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Adulto , Idoso , Aloenxertos , Ativação do Complemento/imunologia , Feminino , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/imunologia , Antígenos HLA/imunologia , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Estudos Prospectivos , Fatores de Risco , Doadores de Tecidos
5.
Am J Transplant ; 17(9): 2300-2311, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28251805

RESUMO

The classic pathway (CP) of complement is believed to significantly contribute to alloantibody-mediated transplant injury, and targeted complement inhibition is currently considered to be a promising approach for preventing rejection. Here, we investigated the mode of action and efficacy of the humanized anti-C1s monoclonal antibody TNT009 and its parental mouse variant, TNT003, in preclinical in vitro models of HLA antibody-triggered CP activation. In flow cytometric assays, we measured the attachment of C1 subcomponents and C4/C3 split products (C4b/d, C3b/d) to HLA antigen-coated flow beads or HLA-mismatched aortic endothelial cells and splenic lymphocytes. Anti-C1s antibodies profoundly inhibited C3 activation at concentrations >20 µg/mL, in both solid phase and cellular assays. While C4 activation was also prevented, this was not the case for C1 subcomponent attachment. Analysis of serum samples obtained from 68 sensitized transplant candidates revealed that the potency of inhibition was related to the extent of baseline CP activation. This study demonstrates that anti-C1s antibodies TNT009 and TNT003 are highly effective in blocking HLA antibody-triggered complement activation downstream of C1. Our results provide the foundation for clinical studies designed to investigate the potential of TNT009 in the treatment or prevention of complement-mediated tissue injury in sensitized transplant recipients.


Assuntos
Anticorpos Monoclonais/farmacologia , Ativação do Complemento/imunologia , Complemento C1s/imunologia , Rejeição de Enxerto/tratamento farmacológico , Antígenos HLA/imunologia , Isoanticorpos/efeitos adversos , Transplante de Rim/efeitos adversos , Animais , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Falência Renal Crônica/imunologia , Falência Renal Crônica/cirurgia , Testes de Função Renal , Camundongos , Prognóstico
6.
Prog Mol Subcell Biol ; 37: 231-53, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15825646

RESUMO

This chapter deals with the discovery of sorbicillactone A, as an illustrative example of the fruitful cooperation within BIOTECmarin--its isolation and chemical characterization, and its biological activities. Sorbicillactone A was isolated from a strain of Penicillium chrysogenum cultured from a sample of the Mediterranean sponge Ircinia fasciculata; it possesses a unique bicyclic lactone structure, seemingly derived from sorbicillin. Among the numerous known sorbicillin-derived structures, it is the first found to contain nitrogen and thus the first representative of a novel type of 'sorbicillin alkaloids', apparently originating from a likewise remarkable biosynthesis. Furthermore, the compound exhibits promising activities in several mammalian and viral test systems, in particular a highly selective cytostatic activity against murine leukemic lymphoblasts (L5178y) and the ability to protect human T cells against the cytopathic effects of HIV-1. These properties qualify sorbicillactone A or one of its derivatives for animal and (hopefully) also future therapeutic human trials.


Assuntos
Alcaloides/química , Benzofuranos/química , Benzofuranos/metabolismo , Fungos/metabolismo , Lactonas/química , Animais , Fármacos Anti-HIV/farmacologia , Antifúngicos/farmacologia , Apoptose , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Dicroísmo Circular , Relação Dose-Resposta a Droga , Humanos , Lactonas/metabolismo , Leucemia L5178/tratamento farmacológico , Leucemia L5178/virologia , Espectrometria de Massas , Camundongos , Modelos Químicos , Penicillium/metabolismo , Poríferos/microbiologia , Linfócitos T/metabolismo , Linfócitos T/virologia , Fatores de Tempo
7.
SAR QSAR Environ Res ; 14(5-6): 321-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14758976

RESUMO

Web-based tools offer many advantages for processing chemical information, most notably ease of use and high interactivity. Therefore more and more pharmaceutical companies are using web technology to deliver sophisticated molecular processing tools directly to the desks of their chemists, to assist them in the process of designing and developing new drugs. In this paper, the web-based cheminformatics system developed at Novartis and currently used by more than thousand users is described. The system allows various molecular modeling and molecular processing tasks, including the calculation of molecular and substituent properties, property-based virtual screening, visualization of molecules, bioisosteric design, diversity analysis, and support of combinatorial chemistry. The methodology to calculate various molecular properties relevant to drug design is described, including the prediction of intestinal absorption, blood-brain barrier penetration, efflux, and water solubility. Information about the web technology used is also provided.


Assuntos
Desenho de Fármacos , Indústria Farmacêutica , Internet , Informática Médica , Modelos Moleculares , Humanos , Relação Quantitativa Estrutura-Atividade , Interface Usuário-Computador
8.
J Nat Prod ; 64(4): 415-20, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11325219

RESUMO

Organic-soluble extracts of the twigs of Aglaia oligophylla collected in Vietnam yielded four insecticidal cyclopentatetrahydrobenzofurans of the rocaglamide type including one new natural product (compound 4). Moreover, two cyclopentatetrahydrobenzopyran derivatives, belonging to the aglain and aglaforbesin types, respectively, were also isolated. The aglaforbesin derivative 6 proved likewise to be a new natural product. All isolated rocaglamide, aglain, and aglaforbesin derivatives have a characteristic methylenedioxy substituent linked to C-6 and C-7 or to C-7 and C-8, respectively. Structure elucidation of the new natural products and the determination of the absolute configuration of compound 1 by calculation of its CD spectrum with molecular dynamics simulation are described. All isolated rocaglamide derivatives exhibited strong insecticidal activity toward neonate larvae of the polyphageous pest insect Spodoptera littoralis when incorporated into an artificial diet, with LC(50) values varying between 2.15 and 6.52 ppm.


Assuntos
Benzofuranos/isolamento & purificação , Inseticidas/isolamento & purificação , Rosales/química , Animais , Benzofuranos/química , Dicroísmo Circular , Inseticidas/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Modelos Moleculares , Estrutura Molecular , Spodoptera , Estereoisomerismo
9.
Phytochemistry ; 53(3): 409-16, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10703067

RESUMO

Six tropane alkaloids were isolated from the Sri Lankan endemic plant Erythroxylum zeylanicum O.E. Schulz (Erythroxylaceae) and structurally elucidated by NMR and MS measurements. Three of them, erythrozeylanines A [1R,3R,5S,6R-6-acetoxy-3-(3',4',5'-trimethoxybenzoyloxy)tropane], B [cis-3 beta-(cinnamoyloxy)tropane], and C [cis-6 beta-acetoxy-3 alpha-(cinnamoyloxy)tropane] are new, whereas the others have already been found in other Erythroxylum species. For the first time, the absolute configuration of a tropane alkaloid (erythrozeylanine A) has been determined by quantum chemical CD calculations.


Assuntos
Alcaloides/isolamento & purificação , Plantas/química , Tropanos/química , Alcaloides/química , Estrutura Molecular , Análise Espectral
10.
Eur Arch Otorhinolaryngol ; 252(4): 236-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7546679

RESUMO

In this prospective randomized clinical study a total of 59 patients of both sexes (above 18 years of age) were enrolled. Thirty patients with acute sinusitis were randomly allocated to two treatment groups, one group receiving 1000 mg amoxicillin every 12 h for 10 days and the other group receiving 500 mg amoxicillin every 8 h for 10 days. The median concentration of amoxicillin in nasal secretions was 2.34 micrograms/ml in the 12-h administration group and 1.95 micrograms/ml in the 8-h administration group. Median bioavailability of antibiotic at 8-24 h did not show any statistical differences between the two treatment schemes [probability (Z) = 0.2]. Twenty-nine patients with chronic sinusitis were then randomly allocated to three groups, with patients receiving 1000 mg amoxicillin at 12, 8 or 6 h before nasal and/or sinus surgery was carried out. The mean amoxicillin concentrations in mucosal tissues removed intraoperatively ranged from 0.69 to 0.99 microgram/g samples. Statistical evaluation by analysis of variance did not show any statistically significant differences among the three treatment groups [probability (F) = 0.1705]. In all cases of acute and chronic sinusitis, amoxicillin concentrations exceeded minimum inhibitory concentration values for pathogens common in sinusitis. Our results indicate that 1000 mg amoxicillin administered twice daily produces tissue concentrations high enough to be clinically effective in patients with either acute or chronic sinusitis.


Assuntos
Amoxicilina/farmacocinética , Mucosa Nasal/metabolismo , Penicilinas/farmacocinética , Sinusite/sangue , Doença Aguda , Adulto , Amoxicilina/administração & dosagem , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Masculino , Penicilinas/administração & dosagem , Estudos Prospectivos , Sinusite/tratamento farmacológico
12.
Infection ; 21(4): 259-61, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8225634

RESUMO

In an in vitro study 246 clinical isolates of erythromycin-resistant staphylococci from six hospitals in Austria were investigated for susceptibility to josamycin and other, newer macrolide antibiotics, e.g. roxithromycin and clarithromycin. 71 strains of Staphylococcus aureus showed an MIC > or = 4 mg/l and 100 strains of S. aureus showed an MIC > or = 256 mg/l. In addition, 25 strains of coagulase-negative staphylococci resistant to erythromycin at an MIC of > or = 4 mg/l were investigated. At an MIC of 2 mg/l 57% of the erythromycin-resistant strains of S. aureus were inhibited by josamycin, 25% by clarithromycin and 11.6% by roxithromycin. At an MIC of 2 mg/l 13.3% of erythromycin-resistant coagulase-negative staphylococci were inhibited by josamycin, 10.7% by clarithromycin and 9.3% by roxithromycin. This study suggests that josamycin is still active in vitro against more than 50% of erythromycin-resistant strains of S. aureus. This drug is also more active than roxithromycin and clarithromycin against erythromycin-resistant S. aureus.


Assuntos
Claritromicina/farmacologia , Infecção Hospitalar/tratamento farmacológico , Eritromicina , Josamicina/farmacologia , Roxitromicina/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Infecção Hospitalar/microbiologia , Avaliação de Medicamentos , Resistência Microbiana a Medicamentos , Humanos , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/microbiologia
14.
Eur J Pharmacol ; 208(2): 119-30, 1991 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-1800125

RESUMO

(-)-Emopamil ((S)-emopamil, (2S)-2-isopropyl-5-(methylphenethylamino)- 2-phenylvaleronitrile hydrochloride) is a Ca(2+)-antagonistic phenylalkylamine which also blocks serotonin (5-HT2) receptors and has antiischemic properties. The (-)-[3H]emopamil tissue distribution profile of specific binding is in striking contrast to that observed for (+)-[3H]PN 200-110 or (-)-[3H]desmethoxyverapamil: (-)-[3H]emopamil labels membrane fractions from guinea-pig liver much greater than adrenal gland greater than kidney approximately lung approximately ductus deferens approximately brain approximately skeletal muscle. Binding to liver membrane was saturable (KD = 12.8 nM, Bmax = 35 pmol/mg of protein), stereoselective, reversible (K-1 = 0.22 min-1 at 25 degrees C) and inhibited by tetraethylammonium (IC50: 1.8 mM) greater than Li+ (IC50: 12.5 mM) approximately Na+ (IC50: 13.6 mM) and [NH4+] (IC50: 79.3 mM) but not by Rb+, Cs+ or K+. The high-affinity liver membrane binding sites have a pharmacological profile that is distinct from the phenylalkylamine receptor domain of the voltage-dependent L-type Ca2+ channel. Similar sites exist in brain and other tissues, albeit with a lower density. Amiodarone, butoprozine and amiloride derivatives bind with high affinity whereas 1,4-dihydropyridines do not interact at all. It is suggested that the novel phenylalkylamine site is linked to a sodium-dependent carrier or transport system.


Assuntos
Receptores de Droga/metabolismo , Verapamil/análogos & derivados , Animais , Sítios de Ligação , Cátions/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/ultraestrutura , Di-Hidropiridinas/metabolismo , Cobaias , Fígado/metabolismo , Fígado/ultraestrutura , Masculino , Distribuição Tecidual , Trítio , Verapamil/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...