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1.
Ann Oncol ; 33(6): 602-615, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35263633

RESUMO

BACKGROUND: Atypical EGFR mutations occur in 10%-30% of non-small-cell lung cancer (NSCLC) patients with EGFR mutations and their sensitivity to classical epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKI) is highly heterogeneous. Patients harboring one group of uncommon, recurrent EGFR mutations (G719X, S768I, L861Q) respond to EGFR-TKI. Exon 20 insertions are mostly insensitive to EGFR-TKI but display sensitivity to exon 20 inhibitors. Clinical outcome data of patients with very rare point and compound mutations upon systemic treatments are still sparse to date. PATIENTS AND METHODS: In this retrospective, multicenter study of the national Network Genomic Medicine (nNGM) in Germany, 856 NSCLC cases with atypical EGFR mutations including co-occurring mutations were reported from 12 centers. Clinical follow-up data after treatment with different EGFR-TKIs, chemotherapy and immune checkpoint inhibitors were available from 260 patients. Response to treatment was analyzed in three major groups: (i) uncommon mutations (G719X, S7681, L861Q and combinations), (ii) exon 20 insertions and (iii) very rare EGFR mutations (very rare single point mutations, compound mutations, exon 18 deletions, exon 19 insertions). RESULTS: Our study comprises the largest thus far reported real-world cohort of very rare EGFR single point and compound mutations treated with different systemic treatments. We validated higher efficacy of EGFR-TKI in comparison to chemotherapy in group 1 (uncommon), while most exon 20 insertions (group 2) were not EGFR-TKI responsive. In addition, we found TKI sensitivity of very rare point mutations (group 3) and of complex EGFR mutations containing exon 19 deletions or L858R mutations independent of the combination partner. Notably, treatment responses in group 3 (very rare) were highly heterogeneous. Co-occurring TP53 mutations exerted a non-significant trend for a detrimental effect on outcome in EGFR-TKI-treated patients in groups 2 and 3 but not in group 1. CONCLUSIONS: Based on our findings, we propose a novel nNGM classification of atypical EGFR mutations.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB , Medicina Genômica , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento
2.
ESMO Open ; 9(2): 102237, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38350336

RESUMO

BACKGROUND: In 2019, we reported the first efficacy and safety analysis of EUCROSS, a phase II trial investigating crizotinib in ROS1 fusion-positive lung cancer. At that time, overall survival (OS) was immature and the effect of crizotinib on intracranial disease control remained unclear. Here, we present the final analysis of OS, systemic and intracranial activity, and the impact of co-occurring aberrations. MATERIALS AND METHODS: EUCROSS was a prospective, single-arm, phase II trial. The primary endpoint was best overall response rate (ORR) using RECIST 1.1. Secondary and exploratory endpoints were progression-free survival (PFS), OS, and efficacy in pre-defined subgroups. RESULTS: Median OS of the intention-to-treat population (N = 34) was 54.8 months [95% confidence interval (CI) 20.3 months-not reached (NR); median follow-up 81.4 months] and median all-cause PFS of the response-evaluable population (N = 30) was 19.4 months (95% CI 10.1-32.2 months). Time on treatment was significantly correlated with OS (R = 0.82; P < 0.0001). Patients with co-occurring TP53 aberrations (28%) had a significantly shorter OS [hazard ratio (HR) 11; 95% CI 2.0-56.0; P = 0.006] and all-cause PFS (HR 4.2; 95% CI 1.2-15; P = 0.025). Patients with central nervous system (CNS) involvement at baseline (N = 6; 20%) had a numerically shorter median OS and all-cause PFS. Median intracranial PFS was 32.2 months (95% CI 23.7 months-NR) and the rate of isolated CNS progression was 24%. CONCLUSIONS: Our final analysis proves the efficacy of crizotinib in ROS1-positive lung cancer, but also highlights the devastating impact of TP53 mutations on survival and treatment efficacy. Additionally, our data show that CNS disease control is durable and the risk of CNS progression while on crizotinib treatment is low.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Crizotinibe/farmacologia , Crizotinibe/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas Tirosina Quinases/genética , Estudos Prospectivos , Proteínas Proto-Oncogênicas/genética , Sistema Nervoso Central
3.
Dtsch Tierarztl Wochenschr ; 112(8): 304-6, 2005 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-16218184

RESUMO

Johne's disease is widely seen in dairy herds in Germany. Estimates based primarily on epidemiological surveys in neighbouring states assume that 5 to 15 % of German herds are infected. In the past three years several authors have reported that the causative agent of Johne's disease, Mycobacterium avium subspecies paratuberculosis (MAP), is found ubiquitously in the environment and can be isolated from a number of different animals, including non ruminants. These results imply that MAP should be considered an environmental pathogen. Based on this assumption a concept for control and eradication of Johne's disease is presented aiming at minimizing the future spread of disease and reducing environmental contamination with the pathogen at low costs. The concept includes the classification of herds based on an bulk milk ELISA followed by a robot-compatible bulk milk PCR in ELISA-positive herds only. Due to the comparatively low costs combined with the high specificity of the approach a detection of heavily infected herds ("tip of the iceberg") all over the country would be possible; based on the eradication of strong shedders in these herds the input of MAP into the environment would be reduced considerably.


Assuntos
Doenças dos Bovinos/prevenção & controle , Leite/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/prevenção & controle , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/epidemiologia , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Alemanha/epidemiologia , Mycobacterium avium subsp. paratuberculosis/imunologia , Paratuberculose/diagnóstico , Paratuberculose/epidemiologia , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/veterinária , Sensibilidade e Especificidade
4.
Psychopharmacology (Berl) ; 143(1): 1-7, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10227072

RESUMO

RATIONALE: Several investigators have shown that male rodents are more sensitive than females to morphine's antinociceptive effects. OBJECTIVE: The present study was conducted to determine whether this sex difference is stable after chronic morphine treatment. RESULTS: Acutely administered morphine produced significantly greater hotplate and tail withdrawal antinociception in males than in females. In contrast, there were no sex differences in morphine's hotplate or tail withdrawal effects under repeated (1-week interval) dosing conditions. In a separate group of rats, after 2 weeks of twice-daily morphine treatment (10-20 mg/kg per injection), the ED50 for morphine's antinociceptive effects increased approximately 6.9-fold in males versus only 3.7-fold in females; chronic morphine treatment also disrupted the estrous cycle of females. In a separate group of rats treated with 10 mg/kg morphine twice daily for 5 days, treatment with naloxone (1.0 mg/kg) on day 6 produced greater withdrawal scores in males than in females. CONCLUSIONS: These experiments demonstrate sex differences in development of tolerance to and dependence on morphine in the rat.


Assuntos
Analgésicos Opioides/farmacologia , Dependência de Morfina/fisiopatologia , Morfina/farmacologia , Animais , Relação Dose-Resposta a Droga , Tolerância a Medicamentos , Estro/fisiologia , Feminino , Masculino , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Medição da Dor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Caracteres Sexuais , Síndrome de Abstinência a Substâncias/fisiopatologia , Fatores de Tempo
5.
Drug Alcohol Depend ; 46(1-2): 31-40, 1997 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-9246551

RESUMO

Given gender differences in human drug use and dependence, this study examined sex differences in reinforcement processes that may underlie such behavior. A psychophysical determination of reinforcement threshold was made using an intracranial self-stimulation (ICSS) paradigm, electrically activating the medial forebrain bundle (MFB) as it passes through the lateral hypothalamus (LH). Using this response rate-independent procedure, basal reinforcement thresholds were not significantly different in male vs. female rats (119.4 +/- 3.3 microA vs. 110.8 +/- 4.0 microA, respectively; N = 8/sex). Further, baseline reinforcement threshold did not fluctuate systematically across stages of the estrous cycle in female rats. The psychostimulants D-amphetamine (0.056-0.56 mg/kg s.c.) and cocaine (1.8-18.0 mg/kg i.p.) dose-dependently lowered reinforcement threshold, with no significant sex difference. The opioid morphine (0.56-5.6 mg/kg s.c.) did not significantly lower reinforcement threshold in either sex. These results contrast those of some previous studies that have used response rate-dependent measures of reinforcement threshold; procedures which are less rate-dependent may be more appropriate when examining subject variables such as sex and stage of estrous.


Assuntos
Região Hipotalâmica Lateral/fisiologia , Feixe Prosencefálico Mediano/fisiologia , Motivação , Autoestimulação/fisiologia , Animais , Mapeamento Encefálico , Estimulantes do Sistema Nervoso Central/farmacologia , Cocaína/farmacologia , Dextroanfetamina/farmacologia , Estimulação Elétrica , Estro/efeitos dos fármacos , Estro/fisiologia , Feminino , Humanos , Região Hipotalâmica Lateral/efeitos dos fármacos , Masculino , Feixe Prosencefálico Mediano/efeitos dos fármacos , Morfina/farmacologia , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Ratos , Ratos Sprague-Dawley , Autoestimulação/efeitos dos fármacos , Caracteres Sexuais
6.
Drug Alcohol Depend ; 42(1): 27-37, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8889401

RESUMO

Eight female and 8 male rats were trained to discriminate 5.6 mg/kg i.p. cocaine from saline on 2-lever, food-reinforced drug discrimination procedure. Female rats acquired the cocaine discrimination in approximately the same number of sessions that males did (43 +/- 7 vs. 51 +/- 9 sessions, respectively), and the ED50 for cocaine discrimination was nearly equivalent in female and male rats (2.46 +/- 0.41 vs. 2.32 +/- 0.49 mg/kg, respectively). The time course for cocaine discrimination was similar in female and male rats, except the offset of cocaine's effects occurred significantly earlier in females than in males. D-Amphetamine dose-dependently substituted for cocaine in all 7 males and 6 of 7 females tested, with no significant sex difference in the ED50 values for D-amphetamine substitution. None of the three opioid agonists tested, morphine (mu), U69,593 (kappa) or BW373U86 (delta), fully substituted for cocaine in rats of either sex. The dopamine antagonist fluphenazine blocked the discriminative stimulus effects of cocaine to approximately the same extent in both sexes. Further drug discrimination training with a higher dose of cocaine, 10 mg/kg, did not significantly alter the ED50 for cocaine discrimination, and there was still no significant sex difference in ED50 values (3.50 +/- 0.39 vs. 2.36 +/- 0.41 mg/kg in females vs. males, respectively). In these same rats, however, cocaine (1-10 mg/kg) produced significantly greater locomotor activation in females than in males on a test of spontaneous locomotor activity. Thus, these results suggest that there are few sex differences in discriminative stimulus effects of cocaine, even at doses that produce significantly different locomotor responses in female versus male rats.


Assuntos
Cocaína/farmacologia , Aprendizagem por Discriminação/efeitos dos fármacos , Animais , Dextroanfetamina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Injeções Intraperitoneais , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fatores Sexuais
7.
Behav Pharmacol ; 7(8): 764-778, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11224471

RESUMO

Nine female and ten male rats were trained to discriminate 3.0mg/kg s.c. morphine from saline. The six female rats that acquired and maintained the morphine discrimination did so in significantly fewer sessions than the eight males did (28 +/- 5 vs 51 +/- 9 sessions, respectively), and the ED(50) for morphine substitution was significantly lower in females (0.69 +/- 0.15 vs 1.28 +/- 0.20mg/kg). The time course of morphine substitution was approximately equivalent in females and males. The µ agonist fentanyl completely substituted for morphine in both sexes, with no sex difference in potency to substitute for morphine. The µ agonist buprenorphine partially or completely substituted for morphine in all females and five of six males, but at a lower dose in females (ED(50) 0.009 +/- 0.002 vs 0.019 +/- 0.006mg/kg). The delta agonist BW373U86 partially substituted for morphine in both sexes, with no potency differences; the kappa agonist U69,593 and the non-opioid cocaine did not substitute for morphine in either sex. On a test of spontaneous locomotor activity, morphine increased locomotion to a slightly but not significantly greater extent in males than in females. Morphine also produced significantly greater hotplate antinociception in males than in females. Further drug discrimination training with a lower dose of morphine, 1.0mg/kg, decreased the ED(50) for morphine substitution in females and males to 0.26 +/- 0.06 vs 0.45 +/- 0.11mg/kg, respectively (not significant). In a separate group of age-matched rats, there was no sex difference in brain or plasma levels of morphine measured via HPLC 20min post-injection, the pretreatment time used to examine behavioral effects of morphine. The HPLC results, plus the fact that sex differences were not the same for all behavioral effects of morphine, suggest that sex differences in discriminative stimulus effects of morphine are not due to differential pharmacokinetics. The possibility that sex differences in morphine discrimination reflect sex differences in opioid receptor pharmacology, or differential reinforcement between morphine and saline levers for males but not females, is discussed.

8.
Photochem Photobiol ; 71(2): 116-23, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10687382

RESUMO

We investigated the effect of UV radiation on early signaling events in the response of young tomato plants (Lycopersicon esculentum) to wounding. Ultraviolet-C (< 280 nm) and UVB/UVA (280-390 nm) radiation both induced 48 kDa myelin basic protein kinase activity in leaves. The activation was associated with phosphorylation of tyrosine residues on the kinase, which is indicative of protein kinases of the mitogen-activated protein kinase family. Ultraviolet-C irradiation resulted in a strong proteinase inhibitor synthesis, as reported previously (Conconi et al., Nature 383, 826-829, 1996). Under the conditions used, UVB/UVA radiation did not induce proteinase inhibitor synthesis but resulted in a strong potentiation of systemic proteinase inhibitor synthesis in response to wounding. The UVB/UVA-irradiated plants that were subsequently wounded accumulated 2.5-4-fold higher levels of proteinase inhibitor I when compared to wounded non-irradiated plants. The potentiating effect was most prominent in the systemic unwounded leaf of a wounded plant. Levels of 12-oxo-phytodienoic acid and jasmonic acid that have been well documented to increase in response to wounding were not detected in response to UVB/UVA irradiation alone. The effect of UVB/UVA radiation in potentiating plant defense signaling should be further considered as a factor that may influence the ecological balance between plants and their predators.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/efeitos da radiação , Transdução de Sinais/efeitos da radiação , Solanum lycopersicum/fisiologia , Raios Ultravioleta , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Ativação Enzimática/efeitos da radiação , Quinase 3 da Glicogênio Sintase , Solanum lycopersicum/enzimologia , Solanum lycopersicum/efeitos da radiação , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Transdução de Sinais/fisiologia
9.
Exp Clin Psychopharmacol ; 9(2): 198-208, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11518096

RESUMO

Morphine was administered to Sprague-Dawley rats twice daily at 0, 3, 10, and 20 mg/kg/ injection during Weeks 1, 2, 3, and 4, respectively; responding for medial forebrain bundle stimulation was assessed 1, 2, and 3 hr after morning injections in female versus male rats. There were no sex differences in responding under control conditions (Week 1). Morphine's effect on response rate depended on dose, time post-injection, stimulation frequency, and day of treatment. Significant sex differences in morphine's effects occurred at 10 mg/kg, which decreased responding more in males at 1 hr and increased responding more in females at 2 hr, at some frequencies and on some test days. Similar trends were observed at other frequencies, test days, and doses. Morphine's differential effect in males versus females in this procedure suggests that sex comparisons of opioid effects in many animal models may be influenced by sex differences in opioid effects on behavioral output.


Assuntos
Condicionamento Operante/efeitos dos fármacos , Morfina/farmacologia , Entorpecentes/farmacologia , Animais , Relação Dose-Resposta a Droga , Estimulação Elétrica , Eletrodos Implantados , Feminino , Masculino , Feixe Prosencefálico Mediano/fisiologia , Ratos , Ratos Sprague-Dawley
10.
Pharmazie ; 46(2): 103-5, 1991 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-1852756

RESUMO

Merbarone [5-(N-phenylcarboxamido)-2-thiobarbituric acid] was developed to clinical trial stage on the basis of its curetive activity against P388 and L1210 leukemias. In the present paper the synthesis of new thioanalogues of pento- and hexobarbital is described. All new compounds were characterized by their spectroscopic data.


Assuntos
Antineoplásicos/síntese química , Tiobarbitúricos/síntese química , Animais , Leucemia L1210/tratamento farmacológico , Leucemia P388/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Camundongos , Tiobarbitúricos/análise , Tiobarbitúricos/farmacologia
11.
Pharmazie ; 45(9): 668-70, 1990 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-2284308

RESUMO

Two drugs (chlorthenoxazine, amobarbital) were converted into their S-analogues derivatives via thiation with the P4S10-pyridine complex. The identity of structure isomers was confirmed by 13C NMR. A preliminary evaluation for their biological activities revealed that trithioamobarbital exhibits some notable spasmolytic effects. The substitution of oxygen by sulphur in chlorthenoxazine resulted in a complete loss of antiinflammatory activity.


Assuntos
Amobarbital/análogos & derivados , Oxazinas/farmacologia , Amobarbital/síntese química , Amobarbital/farmacologia , Analgésicos/síntese química , Analgésicos/farmacologia , Animais , Benzoxazinas , Espectroscopia de Ressonância Magnética , Camundongos , Oxazinas/síntese química , Parassimpatolíticos/síntese química , Tempo de Reação
12.
Eur J Radiol ; 70(3): 561-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18434064

RESUMO

OBJECTIVES: Implementation of an experimental model to compare cartilage MR imaging by means of histological analyses. MATERIAL AND METHODS: MRI was obtained from 4 patients expecting total knee replacement at 1.5 and/or 3T prior surgery. The timeframe between pre-op MRI and knee replacement was within two days. Resected cartilage-bone samples were tagged with Ethi-pins to reproduce the histological cutting course. Pre-operative scanning at 1.5 T included following parameters for fast low angle shot (FLASH: TR/TE/FA=33 ms/6 ms/30 degrees, BW=110 kHz, 120 mm x 120 mm FOV, 256 x 256 matrix, 0.65 mm slice-thickness) and double echo steady state (DESS: TR/TE/FA=23.7 ms/6.9 ms/40 degrees, BW=130 kHz, 120 x 120 mm FOV, 256 x 256 matrix, 0.65 mm slice-thickness). At 3T, scan parameters were: FLASH (TR/TE/FA=12.2 ms/5.1 ms/10 degrees, BW=130 kHz, 170 x 170 mm FOV, 320 x 320, 0.5mm slice-thickness) and DESS (TR/TE/FA=15.6 ms/4.5 ms/25 degrees, BW=200 kHz, 135 mm x 150 mm FOV, 288 x 320 matrix, 0.5mm slice-thickness). Imaging of the specimens was done the same day at 1.5 T. MRI (Noyes) and histological (Mankin) score scales were correlated using the paired t-test. Sensitivity and specificity for the detection of different grades of cartilage degeneration were assessed. Inter-reader and intra-reader reliability was determined using Kappa analysis. RESULTS: Low correlation (sensitivity, specificity) was found for both sequences in normal to mild Mankin grades. Only moderate to severe changes were diagnosed with higher significance and specificity. The use of higher field-strengths was advantageous for both protocols with sensitivity values ranging from 13.6% to 93.3% (FLASH) and 20.5% to 96.2% (DESS). Kappa values ranged from 0.488 to 0.944. CONCLUSIONS: Correlating MR images with continuous histological slices was feasible by using three-dimensional imaging, multi-planar-reformat and marker pins. The capability of diagnosing early cartilage changes with high accuracy could not be proven for both FLASH and DESS.


Assuntos
Biópsia/métodos , Cartilagem Articular/patologia , Imageamento por Ressonância Magnética/métodos , Modelos Teóricos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Skeletal Radiol ; 36(4): 315-20, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17219231

RESUMO

OBJECTIVE: The aim of this study was to evaluate the longitudinal reproducibility of cartilage volume and surface area measurements in moderate osteoarthritis (OA) of the knee. MATERIALS AND METHODS: We analysed 5 MRI (GE 1.5T, sagittal 3D SPGR) data sets of patients with osteoarthritis (OA) of the knee (Kellgren Lawrence grade I-II). Two scans were performed: one baseline scan and one follow-up scan 3 months later (96 +/- 10 days). For segmentation, 3D Slicer 2.5 software was used. Two segmentations were performed by two readers independently who were blinded to the scan dates. Tibial and femoral cartilage volume and surface were determined. Longitudinal and cross-sectional precision errors were calculated using the standard deviation (SD) and coefficient of variation (CV%=100x[SD/mean]) from the repeated measurements in each patient. The in vivo reproducibility was then calculated as the root mean square of these individual reproducibility errors. RESULTS: The cross-sectional root mean squared coefficient of variation (RMSE-CV) was 1.2, 2.2 and 2.4% for surface area measurements (femur, medial and lateral tibia respectively) and 1.4, 1.8 and 1.3% for the corresponding cartilage volumes. Longitudinal RMSE-CV was 3.3, 3.1 and 3.7% for the surface area measurements (femur, medial and lateral tibia respectively) and 2.3, 3.3 and 2.4% for femur, medial and lateral tibia cartilage volumes. CONCLUSION: The longitudinal in vivo reproducibility of cartilage surface and volume measurements in the knee using this segmentation method is excellent. To the best of our knowledge we measured, for the first time, the longitudinal reproducibility of cartilage volume and surface area in participants with mild to moderate OA.


Assuntos
Pesos e Medidas Corporais/métodos , Cartilagem Articular/patologia , Articulação do Joelho/patologia , Osteoartrite do Joelho/diagnóstico , Adulto , Idoso , Estudos Transversais , Feminino , Seguimentos , Humanos , Imageamento Tridimensional/métodos , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes
14.
Arzneimittelforschung ; 30(8): 1250-2, 1980.
Artigo em Alemão | MEDLINE | ID: mdl-7192137

RESUMO

Based on the concept of the anellated heterocycle as the common structural characteristic of a series of antiinflammatory agents, 5-nitrobenzotriazole (1) was caused to react with cinnamoyl chloride (2a) and 4-fluorobenzoyl chloride (2b). The structure of the end products 1-cinnamoyl-5-nitrobenzotriazole (3a) and 1-(4-fluorobenzoyl)-5-nitrobenzotriazole (3b) is supported spectroscopically. 3a exhibits marked antiinflammatory activity.


Assuntos
Anti-Inflamatórios/síntese química , Triazóis/síntese química , Animais , Artrite Experimental/tratamento farmacológico , Ratos , Triazóis/farmacologia
15.
Arch Pharm (Weinheim) ; 324(3): 173-6, 1991 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-1859252

RESUMO

The reactions of 2,4-dichloro-6-diethylamino-1,3,5-triazine (1) with the secondary amines 2a-g lead to the diamino-1,3,5-triazines 3a-e and the melamines 4a and 4b. The structures of the reaction products were established spectroscopically (IR, 1H-NMR, and MS).


Assuntos
Antineoplásicos/síntese química , Triazinas/síntese química , Antineoplásicos/química , Dietilaminas/síntese química , Dietilaminas/química , Dietilaminas/farmacologia , Triazinas/química , Triazinas/farmacologia
16.
Proc Natl Acad Sci U S A ; 94(20): 11085-9, 1997 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-9380763

RESUMO

In response to wounding, a 48-kDa myelin basic protein (MBP) kinase is activated within 2 min, both locally and systemically, in leaves of young tomato plants. The activating signal is able to pass through a steam girdle on the stem, indicating that it moves through the xylem and does not require intact phloem tissue. A 48-kDa MBP kinase is also activated by the 18-amino acid polypeptide systemin, a potent wound signal for the synthesis of systemic wound response proteins (swrps). The kinase activation by systemin is strongly inhibited by a systemin analog having a Thr-17 --> Ala-17 substitution, which is a powerful antagonist of systemin activation of swrp genes. A 48-kDa MBP kinase activity also increases in response to polygalacturonic acid and chitosan but not in response to jasmonic acid or phytodienoic acid. In def1, a mutant tomato line having a defective octadecanoid pathway, the 48-kDa MBP kinase is activated by wounding and systemin as in the wild-type plants. This indicates that MBP kinase functions between the perception of primary signals and the DEF1 gene product. In response to wounding, the MBP kinase is phosphorylated on phosphotyrosine residues, indicating a relationship to the mitogen-activated protein kinase family of protein kinases.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Oligossacarídeos/metabolismo , Peptídeos/fisiologia , Folhas de Planta/enzimologia , Solanum lycopersicum/enzimologia , Animais , Ativação Enzimática , Quinase 3 da Glicogênio Sintase , Larva/enzimologia , Solanum lycopersicum/genética , Manduca/embriologia , Manduca/enzimologia , Mutação , Fosforilação , Proteínas de Plantas/fisiologia
17.
Proc Natl Acad Sci U S A ; 97(16): 8862-7, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10922047

RESUMO

Systemin-mediated defense signaling in tomato (Lycopersicon esculentum) plants is analogous to the cytokine-mediated inflammatory response in animals. Herein, we report that the initiation of defense signaling in suspension-cultured cells of Lycopersicon peruvianum by the peptide systemin, as well as by chitosan and beta-glucan elicitor from Phytophtora megasperma, is inhibited by the polysulfonated naphtylurea compound suramin, a known inhibitor of cytokine and growth factor receptor interactions in animal cells. Using a radioreceptor assay, we show that suramin interfered with the binding of the systemin analog (125)I-Tyr-2, Ala-15-systemin to the systemin receptor with an IC(50) of 160 microM. Additionally, labeling of the systemin receptor with a photoaffinity analog of systemin was inhibited in the presence of suramin. Receptor-mediated tyrosine phosphorylation of a 48-kDa mitogen-activated protein kinase and alkalinization of the medium of suspension-cultured cells in response to systemin and carbohydrate elicitors were also inhibited by suramin. The inhibition of medium alkalinization by suramin was reversible in the presence of high concentrations of systemin and carbohydrate elicitors. Calyculin A and erythrosin B, intracellular inhibitors of phosphatases and plasma membrane proton ATPases, respectively, both induce medium alkalinization, but neither response was inhibited by suramin. The polysulfonated compound heparin did not inhibit systemin-induced medium alkalinization. NF 007, a suramin derivative, induced medium alkalinization, indicating that neither NF 007 nor heparin interact with elicitor receptors like suramin. The data indicate that cell-surface receptors in plants show some common structural features with animal cytokine and growth factor receptors that can interact with suramin to interfere with ligand binding.


Assuntos
Quitina/análogos & derivados , Glucanos/biossíntese , Peptídeos/metabolismo , Plantas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Suramina/farmacologia , Quitina/metabolismo , Quitosana , Eritrosina/farmacologia , Toxinas Marinhas , Oxazóis/farmacologia , Fosforilação , Células Vegetais , Plantas/metabolismo , Inibidores de Proteases/metabolismo , Ligação Proteica , Tirosina/metabolismo
18.
Proc Natl Acad Sci U S A ; 98(22): 12843-7, 2001 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-11675511

RESUMO

A 5-kDa polypeptide was isolated from tobacco leaves that induced a rapid alkalinization of the culture medium of tobacco suspension-cultured cells and a concomitant activation of an intracellular mitogen-activated protein kinase. An N-terminal sequence was obtained, and a cDNA coding for the 49-aa polypeptide was isolated from a tobacco cDNA library. The cDNA encoded a preproprotein of 115 amino acids that contained the polypeptide at its C terminus. A search among known expressed sequence tags revealed that genes encoding Rapid ALkalinization Factor (RALF) preproproteins were present in various tissues and organs from 16 species of plants representing 9 families. A tomato homolog of the polypeptide was synthesized and, when supplied to germinating tomato and Arabidopsis seeds, it caused an arrest of root growth and development. Although its specific role in growth has not been established, the polypeptide joins the ranks of the increasing number of polypeptide hormones that are known to regulate plant stress, growth, and development.


Assuntos
Fenômenos Fisiológicos Vegetais , Proteínas de Plantas/isolamento & purificação , Sequência de Aminoácidos , Sequência de Bases , Dados de Sequência Molecular , Peso Molecular , Proteínas de Plantas/química , Proteínas de Plantas/fisiologia , Sinais Direcionadores de Proteínas
19.
Nature ; 411(6839): 817-20, 2001 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-11459063

RESUMO

Some animal and yeast hormone genes produce prohormone polypeptides that are proteolytically processed to produce multiple copies of hormones with the same or different functions. In plants, four polypeptides have been identified that can be classed as hormones (intercellular chemical messengers) but none are known to be produced as multiple copies from a single precursor. Here we describe a polyprotein hormone precursor, present in tobacco plants, that gives rise to two polypeptide hormones, as often found in animals and yeast. The tobacco polypeptides activate the synthesis of defensive proteinase-inhibitor proteins in a manner similar to that of systemin, an 18-amino-acid polypeptide found in tomato plants. The two tobacco polypeptides are derived from each end of a 165-amino-acid precursor that bears no homology to tomato prosystemin. The data show that structurally diverse polypeptide hormones in different plant species can serve similar signalling roles, a condition not found in animals or yeast.


Assuntos
Nicotiana/metabolismo , Reguladores de Crescimento de Plantas/biossíntese , Plantas Tóxicas , Poliproteínas/metabolismo , Precursores de Proteínas/metabolismo , Sequência de Aminoácidos , Células Cultivadas , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Inibidores de Proteases/metabolismo
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