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1.
Acta Neurochir Suppl ; 96: 398-401, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16671493

RESUMO

INTRODUCTION: Brain edema may be life threatening. The mechanisms underlying the development of traumatic brain edema are still unclear; however, mixed mechanisms including vasogenic, ischemic, and neurotoxic types of edema may be contributors. Recent studies indicate that astrocytes, aquaporins (AQPs; a protein family of water channels), and vascular endothelial growth factor (VEGF) may have important roles in the formation and resolution of brain edema. We studied the expression of AQPs and VEGF in the edematous brain. METHODS: We investigated the expression of AQP1, AQP4, and vascular endothelial growth factor (VEGF) in contusional brain tissue surgically obtained from 6 patients. Glial fibrillary acidic protein (GFAP) was also stained to detect astrocytes and to clarify the location of those proteins. The specimens received immunohistological staining and 3-color immunofluorescent staining, and were observed using confocal laser scanning microscopy. RESULTS: AQP1, AQP4, and VEGF were co-expressed in GFAP-positive astrocytes. AQP1 and AQP4 were expressed strongly in astrocytic end-feet. The astrocytes were located in the edematous tissue, and some cells surrounded cerebral capillaries. CONCLUSION: Our results suggest that AQP1, AQP4, and VEGF are induced in astrocytes located in and surrounding edematous tissue. Those astrocytes may regulate the water in- and out-flow in the injured tissue.


Assuntos
Aquaporina 1/metabolismo , Aquaporina 4/metabolismo , Astrócitos/metabolismo , Lesões Encefálicas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adolescente , Adulto , Idoso , Lesões Encefálicas/complicações , Células Cultivadas , Humanos , Pessoa de Meia-Idade , Distribuição Tecidual
2.
Acta Neurochir Suppl ; 86: 277-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14753452

RESUMO

BACKGROUND: Brain oedema associated with cerebral contusion can be life-threatening. Mechanisms of the development of brain oedema are still unclear. METHOD: We investigated the expression of vascular endothelial growth factor (VEGF) and its receptor VEGFR-2 (KDR/Flk-1) in the contusional brain tissue obtained during neurosurgery from 5 patients. FINDINGS: VEGF is expressed in some but not all the astrocytes, and KDR/Flk-1 is expressed in vascular endothelial cells in the con-tusional tissue as early as 3 hours after onset. CONCLUSION: The results suggested that the VEGF is induced in the contusional tissue in the very early period after onset, and that it increases capillary permeability via KDR/Flk-1 resulting in vasogenic type brain oedema.


Assuntos
Edema Encefálico/etiologia , Edema Encefálico/metabolismo , Lesões Encefálicas/complicações , Encéfalo/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adolescente , Adulto , Astrócitos/metabolismo , Lesões Encefálicas/fisiopatologia , Permeabilidade Capilar , Corantes , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Amarelo de Eosina-(YS) , Feminino , Corantes Fluorescentes , Hematoxilina , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Coloração e Rotulagem , Fatores de Tempo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
3.
Bioorg Med Chem ; 9(7): 1667-71, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11425566

RESUMO

Ru(II)/Ru(III) polypyridyl complexes containing 2,6-(2'-benzimidazolyl)-pyridine or chalcone as co-ligands were synthesized and characterized previously (Mishra, L.; Sinha, R. Indian J. Chem., Sec. A 2001, in press. Mishra, L.; Sinha, R. Indian J. Chem., Sec. A, 39A, 2000, 1131). Their interaction with aqueous buffered calf thymus DNA was measured. (Novakova, O.; Kasparkova, J.; Vrana, O.; van Vliet, P. M., Reedijk, J.; Brabec, V., Biochem. 34, 1995, 12369 and these results prompted additional screening for anti-HIV (human immunodeficiency virus) activity against DNA replication in H9 lymphocytes and cytotoxic activity against eight tumor cell lines. The most active compounds were 17 in the former assay (EC(50) < 0.1 microg/mL and TI > 23.1) and 3, 8, 10, and 14 in the latter assay, especially selectively against the 1A9 ovarian cancer cell line (IC(50) = 4.1, 3.8, 3.6, and 2.5 microg/mL, respectively).


Assuntos
Fármacos Anti-HIV/farmacologia , Antineoplásicos/farmacologia , Chalcona/química , Piridinas/química , Rutênio/farmacologia , Fármacos Anti-HIV/química , Antineoplásicos/química , Replicação do DNA/efeitos dos fármacos , DNA Viral/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Ligantes , Neoplasias Ovarianas/patologia , Rutênio/química , Células Tumorais Cultivadas
4.
Phytother Res ; 15(3): 260-2, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11351365

RESUMO

The plant Typhonium flagelliforme (Araceae), commonly known as the 'rodent tuber', is often included as an essential ingredient in various herbal remedies recommended for cancer therapies in Malaysia. Various extracts prepared from either the roots, tubers, stems or leaves were tested for cytotoxic activity on murine P388 leukaemia cells using the MTT assay method. Both the chloroform (IC50 = 6.0 microg/mL) and hexane (IC50 = 15.0 microg/mL) extract from the 'roots and tubers' exhibited weak cytotoxic activity. The hexane extract (IC50 = 65.0 microg/mL) from the 'stems and leaves' exhibited weaker cytotoxic activity than the chloroform extract (IC50 = 8.0 microg/mL). Although the juice extract from the 'roots and tubers' is frequently consumed for cancer treatment, it exhibited poor cytotoxic activity. Further analysis using an amino acid analyser revealed that the juice extract contained a high concentration of arginine (0.874%). A high tryptophan content (0.800%) was confirmed by NMR and HPLC analysis.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Leucemia/prevenção & controle , Magnoliopsida , Plantas Medicinais , Aminoácidos/análise , Animais , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Células Tumorais Cultivadas/efeitos dos fármacos
6.
Bioorg Med Chem Lett ; 10(4): 315-7, 2000 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-10714489

RESUMO

4-Aza-2,3-dehydro-4-deoxypodophyllotoxin analogues 3a-n were synthesized through quinolines 2a-n. Comparison of their cytotoxicity against P-388 leukemia cells revealed that the steric effects of the ring B substituents on the activity are greater than the electronic effects, while the presence of a methoxy group on the ring E is not essential to exhibit potent cytotoxicity. Analogues 3a and 3b proved to be more than twice as cytotoxic as natural podophyllotoxin (1).


Assuntos
Citotoxinas/química , Podofilotoxina/análogos & derivados , Quinolinas/química , Quinolinas/farmacologia , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Citotoxinas/síntese química , Citotoxinas/farmacologia , Concentração Inibidora 50 , Ceratolíticos/síntese química , Ceratolíticos/química , Ceratolíticos/farmacologia , Modelos Moleculares , Podofilotoxina/química , Podofilotoxina/farmacologia , Quinolonas/química , Quinolonas/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas/efeitos dos fármacos
7.
Phytochemistry ; 55(7): 715-20, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11190386

RESUMO

Five steroidal saponins were isolated from the EtOH extract of Cestrium sendtenerianum (Solanaceae), as confirmed by detailed analysis of their 1H, 13C, and two-dimensional NMR spectral data, and by the results of hydrolytic cleavage. The saponins were revealed to contain three hydroxyl groups at the C-1beta, C-2alpha, and C-3beta positions in the spirostanol skeleton, and to bear a di- or triglycoside at C-3 as the common structural features. One of the compounds, a spirostanol triglycoside, showed weak cytotoxic activity on HL-60 human promyelocytic leukemia cells, with an IC50 value of 7.7 microg/ml.


Assuntos
Saponinas/isolamento & purificação , Solanaceae/química , Esteroides/química , Configuração de Carboidratos , Sequência de Carboidratos , Folhas de Planta/química , Saponinas/química , Análise Espectral
8.
Yakugaku Zasshi ; 119(8): 529-83, 1999 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-10475056

RESUMO

A lot of anticancer agents have been isolated from natural sources, especially from microorganisms and plants. However, there is no special type of compounds for cancer therapy. Various types of substances are effective for various types of cancers and tumors: for instance, alkaloids, lignans, terpenes and steroids, etc. In this report, the authors will describe especially about higher plants.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Plantas Medicinais/química , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Lignanas/química , Lignanas/isolamento & purificação , Lignanas/farmacologia , Conformação Molecular , Neoplasias Experimentais/patologia , Esteroides/química , Esteroides/isolamento & purificação , Esteroides/farmacologia , Terpenos/química , Terpenos/isolamento & purificação , Terpenos/farmacologia , Células Tumorais Cultivadas
9.
No Shinkei Geka ; 26(11): 1019-24, 1998 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-9834498

RESUMO

We report a case of dural arteriovenous fistula (dAVF) of the transverse and sigmoid sinus which developed over five years. The patient was a 64-year-old man, who had a history of congestive heart failure and transient ischemic attack (TIA). No abnormal lesions were detected in the cerebral angiograms five years prior to the time the etiology of his TIA was investigated. He suddenly suffered from left hemiparesis and the CT scan showed right parietal subcortical hemorrhage. Right carotid angiogram demonstrated dAVF of the transverse and sigmoid sinus supplied by the right occipital and ascending pharyngeal arteries. We thought the reason for the subcortical hemorrhage in this patient was due to the disturbance of venous return in the right cerebral hemisphere. We underwent direct embolization of the right transverse sinus by interlocking detachable coils. Postoperative cerebral angiograms demonstrated the disappearance of dAVF and he was discharged. Whether dAVF is a congenital anomaly or not, has been controversial. Since the dAVF in this case had newly developed over five years, it is suggested that dAVF is an acquired lesion.


Assuntos
Fístula Arteriovenosa/etiologia , Dura-Máter/irrigação sanguínea , Fístula Arteriovenosa/diagnóstico por imagem , Fístula Arteriovenosa/cirurgia , Artérias Carótidas/diagnóstico por imagem , Angiografia Cerebral , Humanos , Masculino , Pessoa de Meia-Idade , Trombose dos Seios Intracranianos/etiologia , Fatores de Tempo
10.
Bioorg Med Chem ; 6(7): 1103-15, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9730247

RESUMO

The toad poison bufadienolides including natural and derivatized compounds were tested for their cytotoxic effects on primary liver carcinoma cells PLC/PRF/5 and their structure-cytotoxic activity relationships were studied. For this study, a ligand-binding model was developed by using a pharmacophore mapping program, Distance Comparisons (DISCO). The structural features that are common to the 3D structures of active bufadienolides were identified to provide approach to a 3D QSAR method by using Comparative Molecular Field Analysis (CoMFA) study and to correlate the steric and electrostatic fields of the molecules to their activities. A valuable model which enables prediction of their activities was obtained from the CoMFA analysis, which may be employed for the drug designs of new bufadienolide analogues.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Bufanolídeos/química , Bufanolídeos/farmacologia , Modelos Moleculares , Divisão Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Concentração Inibidora 50 , Neoplasias Hepáticas/patologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
11.
J Nat Prod ; 61(6): 776-80, 1998 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-9644063

RESUMO

Four new quassinoids, cedronolactones A-D (1-4), together with nine known compounds, simalikalactone D (5), chaparrinone (6), chaparrin (7), glaucarubolone (8), glaucarubol (9), samaderine Z (10), guanepolide (11), ailanquassin A (12), and polyandrol (13), were isolated from the wood of Simaba cedron. The chemical structures of 1-4 were elucidated on the basis of their chemical and spectral properties. Cedronolactone A (1) was shown to exhibit a significant in vitro cytotoxicity (IC50 0.0074 microg/mL) against P-388 cells.


Assuntos
Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Lactonas/isolamento & purificação , Plantas Medicinais/química , Alcaloides/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lactonas/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Camundongos , Extratos Vegetais/química , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Células Tumorais Cultivadas , Madeira
12.
Phytochemistry ; 46(3): 521-4, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9332026

RESUMO

Four new flavonoids, luteolin 6-C-(4"-methyl-6"-O-trans-caffeoylglucoside), luteolin 6-C-(6"-O-trans-caffeoylglucoside), luteolin 6-C-(2"-O-trans-caffeoylglucoside), and luteolin 7-O-(6"-p-benzoylglucoside), together with four known ones 5, 4'-dihydroxy-3,6,7,3'-tetramethoxyflavone, luteolin, artemetin and isorhamnetin, were isolated from the root bark of Vitex agnus-castus. The structures were elucidated by spectroscopic means.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Flavonoides/farmacologia , Antineoplásicos Fitogênicos/química , Flavonoides/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas de Bombardeamento Rápido de Átomos
13.
Phytochemistry ; 45(4): 841-5, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9195763

RESUMO

Two new cyclic octapeptides, dichotomin H, cyclo(-Ala-Pro-Thr-Phe-Tyr-P ro-Leu-Ile-), and dichotomin I, cyclo(-Val-Pro-Thr-Phe-Tyr-Pro-Leu-Ile-) have been isolated from the roots of Stellaria dichotoma L. var lanceolata Bge., and their structures were elucidated by extensive two-dimensional NMR methods and chemical degradation.


Assuntos
Peptídeos Cíclicos/isolamento & purificação , Raízes de Plantas/química , Plantas Medicinais/química , Sequência de Aminoácidos , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Inibidores de Ciclo-Oxigenase/química , Inibidores de Ciclo-Oxigenase/isolamento & purificação , Leucemia P388/patologia , Camundongos , Peptídeos Cíclicos/química , Análise Espectral , Células Tumorais Cultivadas
14.
15.
J Nat Prod ; 60(3): 216-8, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9157189

RESUMO

Segetalins G and H (1-2) possessing estrogen-like activity are cyclic pentapeptides from the seeds of Vaccaria segetalis. Their structures, cyclo(-Gly-Ala-Lys-Tyr-Val) (1) and cyclo(-Gly-Phe-Ser-Tyr-Arg-) (2), were determined by interpretation of spectral data.


Assuntos
Estrogênios/isolamento & purificação , Peptídeos Cíclicos/isolamento & purificação , Sementes/química , Animais , Estrogênios/farmacologia , Feminino , Espectroscopia de Ressonância Magnética , Conformação Molecular , Ovariectomia , Peptídeos Cíclicos/farmacologia , Conformação Proteica , Ratos , Ratos Sprague-Dawley , Útero/efeitos dos fármacos , Útero/crescimento & desenvolvimento
16.
Bioorg Med Chem ; 5(3): 631-6, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9113340

RESUMO

Thionation of estrogen-like active cyclic peptides, segetalins A (1) and B (2), with Lawesson's reagent provided each two thiosegetalins; thiosegetalin A1 [Gly-1-psi(CS-NH)-Val-2; Trp-5-psi (CS-NH)-Ala-6]segetalin A, thiosegetalin A2 [Gly-1-psi(CS-NH)-Val-2; Ala-6-psi(CS-NH)-Gly-1]segetalin A, thiosegetalin B1 [Gly-1-psi (CS-NH)-Val-2; Ala-3-psi(CS-NH)-Trp-4]segetalin B, and thiosegetalin B2 [Gly-1-psi(CS-NH)-Val-2; Trp-4-psi(CS-NH)-Ala-1]segetalin B. Thiosegetalin A2 only showed estrogen-like activity against ovariectomized rats. On the basis of their conformations analysed by NMR experiments, the backbone conformation was considered to play an important role in estrogen-like activity for segetalins.


Assuntos
Estrogênios/química , Peptídeos Cíclicos/química , Sementes/química , Compostos de Sulfidrila , Animais , Estrogênios/farmacologia , Feminino , Espectroscopia de Ressonância Magnética , Tamanho do Órgão/efeitos dos fármacos , Ovariectomia , Peptídeos Cíclicos/farmacologia , Conformação Proteica , Ratos , Útero/efeitos dos fármacos
17.
Phytochemistry ; 44(6): 1115-9, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9101665

RESUMO

Eighteen dammarane-type triterpenes were obtained from the whole plant of Cleome africana by means of cytotoxic bioassay-directed fractionation. Twelve of them were novel compounds whose structures were elucidated by various spectroscopic methods.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Plantas Medicinais , Triterpenos/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/toxicidade , Região do Caribe , Leucemia P388 , Medicina Tradicional , Camundongos , Estrutura Molecular , Triterpenos/química , Triterpenos/toxicidade , Células Tumorais Cultivadas
18.
Phytochemistry ; 44(4): 735-8, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9041720

RESUMO

Three alkaloids, neoharringtonine, homoneoharringtonine and 3'S-hydroxyneoharringtonine, were isolated from the leaves and stems of Cephalotaxus harringtonia var. drupacea. Their structures were established by spectroscopic methods, including two-dimensional NMR and CD spectra, and their antileukaemic activity was evaluated using P-388 leukaemia cells.


Assuntos
Alcaloides/química , Plantas/química , Alcaloides/isolamento & purificação , Animais , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Leucemia P388/patologia , Espectroscopia de Ressonância Magnética , Conformação Molecular , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Células Tumorais Cultivadas
19.
Bioorg Med Chem ; 5(11): 2063-7, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9416423

RESUMO

Three-dimensional structures in DMSO-d0 of segetalins G [cyclo(-Gly-Val-Lys-Tyr-Ala-)] and H [cyclo(-Gly-Tyr-Arg-Phe-Ser-)], cyclic pentapeptides from seeds of Vaccaria segetalis, showing estrogen-like activity, were determined by the distance geometry calculation and restrained energy minimization from NMR data. The backbone structure of segetalin G contains one beta-turn: a beta II-like turn at Tyr4-Ala5, and that of segetalin H one beta-turn: a beta II' turn at Gly1-Tyr2 and one gamma-turn at Arg3-Phe4-Ser5 sequence. The results of distance comparison analysis proposed a pharmacophore model of estrogen-like cyclic peptides, segetalins.


Assuntos
Estrogênios/química , Peptídeos Cíclicos/química , Proteínas de Plantas/química , Conformação Proteica , Sítios de Ligação , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Sementes/química , Soluções , Relação Estrutura-Atividade , Temperatura
20.
J Neurosurg ; 85(3): 500-2, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8751639

RESUMO

Four years after undergoing a superficial temporal artery-middle cerebral artery bypass procedure, this patient presented with a ruptured aneurysm at the anastomosis site. The ruptured aneurysm caused subarachnoid and intracerebral hemorrhages and was treated by surgically clipping its neck. Characteristics of the aneurysm included: 1) a relatively large size (8 x 6 x 6 mm): 2) a thickened wall; 3) a location apart from the suture line; 4) a projection in a direction consistent with hemodynamic stress; and 5) a time interval from bypass surgery to rupture that lasted 4 years. These features, along with the well-known fact that hemodynamic stress can cause aneurysms, led the authors to believe that this aneurysm was a true one. The authors present a case of this unusual complication following bypass surgery and provide a brief review of the literature.


Assuntos
Artérias Cerebrais/cirurgia , Aneurisma Intracraniano/cirurgia , Anastomose Cirúrgica , Angiografia Cerebral , Artérias Cerebrais/diagnóstico por imagem , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Ruptura Espontânea/diagnóstico por imagem , Ruptura Espontânea/cirurgia
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