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1.
Neth J Med ; 78(4): 191-195, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32641558

RESUMO

Monoclonal gammopathy of undetermined significance (MGUS) is considered an asymptomatic precursor of malignant lymphoid disorders. This case series and literature review shows that these monoclonal gammopathies can cause significant morbidity. We describe a patient with angioedema due to acquired C1-esterase inhibitor deficiency, a patient with cryoglobulinemia type II causing skin vasculitis and glomerulonephritis, and a patient with glomerulonephritis and nephrotic syndrome - all caused by a monoclonal gammopathy that can be classified as MGUS. Clinicians should be familiar with these consequences of monoclonal gammopathies. The term MGUS should only be used in patients without organ damage caused by monoclonal gammopathies.


Assuntos
Angioedemas Hereditários/etiologia , Crioglobulinemia/etiologia , Nefropatias/etiologia , Paraproteinemias/complicações , Paraproteinemias/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino
2.
Clin Exp Allergy ; 48(2): 186-195, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29121432

RESUMO

BACKGROUND: Alpine climate treatment has historically been used in Europe to treat atopic dermatitis (AD), but no randomized trials have been conducted to provide evidence for its effectiveness. OBJECTIVE: To investigate the long-term effectiveness of alpine climate treatment for children with difficult to treat AD. MATERIALS & METHODS: A pragmatic, open, randomized controlled trial was conducted. Children diagnosed with AD that was considered difficult to treat, aged between 8 and 18 years and willing to be treated in Switzerland were randomized to a six-week personalized integrative multidisciplinary treatment period in a clinical setting in the alpine climate (Switzerland) or an outpatient setting in moderate maritime climate (Netherlands). Study assessments were conducted at the Wilhelmina Children's Hospital; an electronic portal was used for the collection of questionnaire data. Primary outcomes were disease activity (SAEASI), quality of life (CDLQI) and catastrophizing thoughts (JUCKKI/JU) 6 months after intervention. Other assessments were immediately and 6 weeks after intervention. Subgroup analyses concerned asthma-related outcomes. Children were randomly assigned to either the intervention or control group using a covariate adaptive randomization method, taking age and asthma diagnosis into account. Children, parents and healthcare professionals involved in treatment were not blinded to group assignment. Data were analysed according to intention-to-treat with linear mixed-effects models for continuous outcomes. The trial is registered at Current Controlled Trials ISCRTN88136485. RESULTS: Between 14 September 2010 and 30 September 2014, 88 children were enrolled in the trial, 84 children were randomized (41 assigned to intervention, 43 to control) of whom 77 completed the intervention (38 of 41 (93%) intervention, 39 of 43 (91%) control) and 74 completed follow-up (38 of 41 (93%) intervention, 36 of 43 (84%) control). Six months after intervention there were no significant differences between the groups on disease activity (SAEASI mean difference -3.4 (95%CI -8.5 to 1.7)), quality of life (CDLQI mean difference -0.3 (95%CI -2.0 to 1.4)) and catastrophizing thoughts (JUCCKI/JU subscale mean difference -0.7 (95%CI -1.4 to -0.0)). Immediately and 6 weeks after intervention, disease activity and quality of life were significantly different in favour of alpine climate treatment. Mean differences on SAEASI were -10.1 (95%CI -14.5 to -5.8) and -8.4 (95%CI -12.2 to -4.6) and on CDLQI -1.9 (95%CI -3.3 to -0.5) and -1.5 (95%CI -2.8 to -0.3) immediately and 6 weeks after the intervention, respectively. There were no long-term differences on asthma-related outcomes. Five serious adverse events occurred during the study period, which were not thought to be related to the treatment. CONCLUSIONS & CLINICAL RELEVANCE: For children with difficult to treat AD, there was no additional long-term benefit of alpine climate treatment, in contrast to the short-term, compared to an outpatient treatment programme in moderate maritime climate, using a personalized integrative multidisciplinary treatment approach.


Assuntos
Clima , Climatoterapia , Dermatite Atópica/terapia , Adolescente , Altitude , Antiasmáticos/farmacologia , Antiasmáticos/uso terapêutico , Criança , Dermatite Atópica/diagnóstico , Dermatite Atópica/epidemiologia , Resistência a Medicamentos , Humanos , Qualidade de Vida , Inquéritos e Questionários , Suíça , Resultado do Tratamento
3.
Org Biomol Chem ; 16(1): 62-69, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29098212

RESUMO

3,7-Dihydroxytropolones (3,7-dHTs) are highly oxygenated troponoids that have been identified as lead compounds for several human diseases. To date, structure-function studies on these molecules have been limited due to a scarcity of synthetic methods for their preparation. New synthetic strategies towards structurally novel 3,7-dHTs would be valuable in further studying their therapeutic potential. Here we describe the successful adaptation of a [5 + 2] oxidopyrilium cycloaddition/ring-opening for 3,7-dHT synthesis, which we apply in the synthesis of a plausible biosynthetic intermediate to the natural products puberulic and puberulonic acid. We have also tested these new compounds in several biological assays related to human immunodeficiency virus (HIV), hepatitis B virus (HBV) and herpes simplex virus (HSV) in order to gain insight into structure-functional analysis related to antiviral troponoid development.


Assuntos
Antivirais/farmacologia , HIV/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Simplexvirus/efeitos dos fármacos , Tropolona/análogos & derivados , Antivirais/síntese química , Antivirais/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Tropolona/síntese química , Tropolona/química , Tropolona/farmacologia
4.
Anaesthesist ; 64(6): 451-5, 2015 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-26031561

RESUMO

Sudden cardiac death (SCD) in young athletes during physical stress is a rare event with an incidence of 1-3 deaths per 100,000 athletes per year. A coronary anomaly is the second most common cause of death following hypertrophic cardiomyopathy. Symptomatic prodromes occur in 20% of cases prior to the SCD event. This case report describes a 35-year-old male who collapsed near the finishing line of a half marathon run. Despite immediate resuscitation attempts and initial return of spontaneous circulation (ROSC), a pulseless electrical activity (PEA) followed and the patient died 1 h after arrival in the resuscitation unit. The autopsy revealed an anomalous left coronary artery (ALCA), which can lead to ischemia of the respective heart muscles under severe stress.


Assuntos
Anomalias dos Vasos Coronários/complicações , Morte Súbita Cardíaca/patologia , Corrida , Adulto , Autopsia , Reanimação Cardiopulmonar , Anomalias dos Vasos Coronários/patologia , Vasos Coronários/patologia , Morte Súbita Cardíaca/etiologia , Eletrocardiografia , Humanos , Masculino , Miocárdio/patologia , Resistência Física
5.
Anal Biochem ; 437(2): 138-43, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23481912

RESUMO

Cannabinoid (CB) receptors are being targeted therapeutically for the treatment of anxiety, obesity, movement disorders, glaucoma, and pain. More recently, cannabinoid agonists have displayed antiproliferative activity against breast cancer and prostate cancer in animal models. To study cannabinoid receptor ligands, we have developed a novel plate-based assay that measures internalization of CB1/CB2 receptors by determining the change in the intracellular levels of the radiolabeled agonists: [(3)H]Win55-212-2 for CB1 and [(3)H]CP55-940 for CB2. The developed plate-based assay was validated by determining IC50 values for known antagonists: AM251, AM281, AM630, and AM6545. The data obtained were consistent with previously reported values, thereby confirming that the assay can be used to determine the functional binding activities (IC50) of antagonists for the CB1 and CB2 receptors. In addition, we demonstrated that the plate-based assay may be used for screening against complex matrices. Specifically, we demonstrated that the plate-based assay was able to identify which extracts of several species of the genus Zanthoxylum had activity at the CB1/CB2 receptors.


Assuntos
Antagonistas de Receptores de Canabinoides/farmacologia , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Animais , Células CHO , Cricetinae , Cricetulus , Humanos , Concentração Inibidora 50 , Ligantes , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Reprodutibilidade dos Testes , Zanthoxylum/química
6.
Neth J Med ; 69(5): 248-55, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21646675

RESUMO

Hypertensive crises are divided into hypertensive urgencies and emergencies. Together they form a heterogeneous group of acute hypertensive disorders depending on the presence or type of target organs involved. Despite better treatment options for hypertension, hypertensive crisis and its associated complications remain relatively common. In the Netherlands the number of patients starting renal replacement therapy because of 'malignant hypertension' has increased in the past two decades. In 2003, the first Dutch guideline on hypertensive crisis was released to allow a standardised evidence-based approach for patients presenting with a hypertensive crisis. In this paper we give an overview of the current management of hypertensive crisis and discuss several important changes incorporated in the 2010 revision. These changes include a modification in terminology replacing 'malignant hypertension' with 'hypertensive crisis with retinopathy and reclassification of hypertensive crisis with retinopathy under hypertensive emergencies instead of urgencies. With regard to the treatment of hypertensive emergencies, nicardipine instead of nitroprusside or labetalol is favoured for the management of perioperative hypertension, whereas labetalol has become the drug of choice for the treatment of hypertension associated with pre-eclampsia. For the treatment of hypertensive urgencies, oral administration of nifedipine retard instead of captopril is recommended as first-line therapy. In addition, a section on the management of hypertensive emergencies according to the type of target organ involved has been added. Efforts to increase the awareness and treatment of hypertension in the population at large may lower the incidence of hypertensive crisis and its complications.


Assuntos
Anti-Hipertensivos/uso terapêutico , Tratamento de Emergência , Hipertensão/tratamento farmacológico , Medicina Interna/normas , Guias de Prática Clínica como Assunto , Antagonistas Adrenérgicos beta/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Captopril/uso terapêutico , Humanos , Hipertensão/classificação , Hipertensão/complicações , Retinopatia Hipertensiva/tratamento farmacológico , Retinopatia Hipertensiva/etiologia , Labetalol/uso terapêutico , Países Baixos , Nicardipino/uso terapêutico , Nifedipino/uso terapêutico , Nitroprussiato/uso terapêutico
7.
Artigo em Inglês | MEDLINE | ID: mdl-19202599

RESUMO

The ubiquitin conjugating system represents a rich source of potential molecular targets for cancer and other diseases. One target of great interest is the RING finger ubiquitin ligase (E3) Hdm2/Mdm2, which is frequently overexpressed in cancer and is a critical E3 for the tumor suppressor p53. For those 50% of tumors that express wild-type p53, agents that inhibit Hdm2 have great potential clinical utility. We summarize our ongoing efforts to identify inhibitors of Hdm2 E3 activity by high-throughput screening of both defined small molecules and natural product extracts. Employing a strategy using both enzymatic and cell-based assays, we have identified inhibitors that block the E3 activity of Hdm2, activate a p53 response, preferentially kill p53-expressing cells, and have the capacity to differentially cause death of transformed cells. Therefore, screening for inhibitors of Hdm2 ubiquitin ligase activity through in vitro assays represents a powerful means of identifying molecules that activate p53 in cancer cells to induce apoptosis. We also discuss the potential of inhibitors of ubiquitin-activating enzyme (E1) that were discovered during these screens. E1 inhibitors may similarly serve as the basis for novel therapeutics. Additionally, they represent unique tools for providing new insights into the ubiquitin conjugating system.


Assuntos
Inibidores Enzimáticos/farmacologia , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Enzimas Ativadoras de Ubiquitina/antagonistas & inibidores , Enzimas Ativadoras de Ubiquitina/metabolismo , Ubiquitina/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Inibidores Enzimáticos/química , Inibidores Enzimáticos/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Ligação Proteica , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores
8.
Ned Tijdschr Geneeskd ; 150(23): 1303-6, 2006 Jun 10.
Artigo em Holandês | MEDLINE | ID: mdl-16821456

RESUMO

A 12-year-old girl and a 57-year-old woman were admitted with fever, general malaise, abdominal pain, nausea and vomiting. Both patients had acute renal insufficiency based on tubulointerstitial nephritis caused by the genus Hantavirus, which was confirmed by blood tests. Both patients recovered spontaneously. The neighbouring countries of France, Germany and Belgium have recently reported 2- to 7-fold increases in the number of Hantavirus infections. Hantavirus is a zoonotic viral disease that is transmitted by mice and is found in humans worldwide. Infection with Hantavirus is associated with severe renal impairment and thrombocytopenia, which usually resolves spontaneously. Recognition of the clinical signs and targeted serological testing can lead to adequate management of the disease. Diagnosing patients with Hantavirus infections will also help to prevent infections in The Netherlands and track epidemiological changes.


Assuntos
Infecções por Hantavirus/epidemiologia , Dor Abdominal/virologia , Bélgica/epidemiologia , Criança , Feminino , França/epidemiologia , Alemanha/epidemiologia , Infecções por Hantavirus/diagnóstico , Infecções por Hantavirus/transmissão , Humanos , Incidência , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Insuficiência Renal/virologia
9.
Eur J Clin Invest ; 33(1): 34-40, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12492450

RESUMO

BACKGROUND: Renal size and function reflect the health of the kidney. These parameters are associated with age, gender and body weight. The kidneys are also influenced by micro- and macrovascular diseases. Atherosclerotic markers and risk factors may influence the age-related changes of renal size and function. METHODS: Data of 1056 patients who entered the SMART-study (Second Manifestations of ARTerial disease) were used to assess the effect of atherosclerosis on the relationship between age and renal size and function and to study the effect of atherosclerosis on renal size and function. Patients who were newly referred to the hospital with manifestations of vascular disease were screened for asymptomatic atherosclerosis with noninvasive tests. The carotid intima-media thickness (IMT) and albuminuria were used as estimates for the atherosclerotic burden. Renal size was defined as the mean pole-to-pole length of both kidneys measured by ultrasonography. Renal function was represented by serum creatinine. RESULTS: Intima-media thickness was a significant effect modifier of the age-renal size relationship (P = 0.041). The increase of serum creatinine with age was more pronounced in the highest tertile of IMT (P = 0.048). Renal size decreased equally with age in patients with and without hypertension or diabetes mellitus (DM). The same held true for the age-renal function relationship. Albuminuria and DM were independent predictors of renal size and function. CONCLUSION: Atherosclerosis accelerates the decrease of renal size and the increase of serum creatinine with age. Renal size and function are determined by albuminuria and DM.


Assuntos
Envelhecimento/patologia , Arteriosclerose/patologia , Rim/patologia , Idoso , Envelhecimento/fisiologia , Albuminúria/patologia , Albuminúria/fisiopatologia , Arteriosclerose/sangue , Arteriosclerose/fisiopatologia , Artéria Carótida Interna/patologia , Creatinina/sangue , Diabetes Mellitus/patologia , Diabetes Mellitus/fisiopatologia , Feminino , Humanos , Hipertensão/patologia , Hipertensão/fisiopatologia , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Regressão , Fatores de Risco , Túnica Íntima/patologia , Túnica Média/patologia
10.
J Nephrol ; 16(6): 807-12, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14736007

RESUMO

BACKGROUND: Atherosclerotic renal artery stenosis (ARAS) is associated with progressive loss of renal function and is one of the most important causes of renal failure in the elderly. Current treatment includes restoration of the renal arterial lumen by endovascular stent placement. However, this treatment only affects damage caused by ARAS due to the stenosis and ensuing post-stenotic ischemia. ARAS patients have severe general vascular disease. Atherosclerosis and hypertension can also damage the kidney parenchyma causing renal failure. Medical treatment focuses on the latter. Lipid-lowering drugs (statins) could reduce renal failure progression and could reduce the overall high cardiovascular risk. The additional effect on preserving renal function of stent placement as compared to medical therapy alone is unknown. Therefore, the STAR-study aims to compare the effects of renal artery stent placement together with medication vs. medication alone on renal function in ARAS patients. METHOD: Patients with an ARAS of > or = 50% and renal failure (creatinine (Cr) clearance < 80 mL/min/1.73 m2) are randomly assigned to stent placement with medication or to medication alone. Medication consists of statins, anti-hypertensive drugs and antiplatelet therapy. Patients are followed for 2 yrs with extended follow-up to 5 yrs. The primary outcome of this study is a reduction in Cr clearance > 20% compared to baseline. This trial will include 140 patients.


Assuntos
Anti-Hipertensivos/uso terapêutico , Arteriosclerose/terapia , Ácidos Heptanoicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Pirróis/uso terapêutico , Obstrução da Artéria Renal/terapia , Artéria Renal , Stents , Angioplastia com Balão , Arteriosclerose/complicações , Arteriosclerose/fisiopatologia , Atorvastatina , Terapia Combinada , Progressão da Doença , Humanos , Rim/fisiopatologia , Obstrução da Artéria Renal/etiologia , Obstrução da Artéria Renal/fisiopatologia , Projetos de Pesquisa
12.
Nucl Med Commun ; 22(9): 971-4, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11505205

RESUMO

BACKGROUND: Captopril renography (CR) has been shown to improve the effectiveness of renal scintigraphy in renovascular hypertension, by inhibiting angiotensin-converting enzyme. CR is particularly sensitive and specific in unilateral renal artery stenosis (RAS), but results in patients with bilateral RAS are less favourable. The aim of this study was to investigate the meaning of abnormal but identical renographic curves in the diagnosis of RAS. PATIENTS AND METHODS: One hundred and fifty-eight patients clinically suspected for renovascular hypertension underwent CR, using 50 MBq (99)Tc(m)-mercaptoacetyltriglycine ((99)Tc(m)-MAG(3)), prior to performing renal angiography. CR was performed 1 h after captopril administration. Renograms were analysed according to the consensus criteria. All patients underwent angiography, considered as the "gold standard" in the detection of the presence of RAS (stenosis >50% was defined as significant). All kidneys were categorized into three groups, scintigraphically as well as angiographically: no stenosis, unilateral stenosis and bilateral stenosis. RESULTS: Out of 158 patients 100 (63%) showed a RAS on angiography (58 (37%) unilateral, 42 (26%) bilateral). The sensitivity and specificity of CR evaluated by patient was 83% and 75%, respectively. Thirty patients with completely identical curves were identified, 21 patients with normal curves and nine patients with abnormal identical curves. All but one patient showed no RAS on the angiogram. In this single patient a unilateral stenosis was found. CONCLUSION: Identical curves on the renogram generally suggest no RAS and are probably due to intrinsic parenchymal disease.


Assuntos
Captopril , Renografia por Radioisótopo , Obstrução da Artéria Renal/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
J Pharmacol Exp Ther ; 297(1): 114-20, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11259534

RESUMO

A series of naturally occurring compounds reported recently by multiple laboratories defines a new small-molecule class sharing a unique benzolactone enamide core structure and diverse biological actions, including inhibition of growth of tumor cells and oncogene-transformed cell lines. Here we show that representative members of this class, including salicylihalamide A, lobatamides A-F, and oximidines I and II inhibit mammalian vacuolar-type (H+)-ATPases (V-ATPases) with unprecedented selectivity. Data derived from the NCI 60-cell antitumor screen critically predicted the V-ATPase molecular target, while specific biochemical assays provided confirmation and further illumination. The compounds potently blocked representative V-ATPases from human kidney, liver, and osteoclastic giant-cell tumor of bone but were essentially inactive against V-ATPases of Neurospora crassa and Saccharomyces cerevisiae and other membrane ATPases. Essential regulation of pH in cytoplasmic, intraorganellar, and local extracellular spaces is provided by V-ATPases, which are ubiquitously distributed among eukaryotic cells and tissues. The most potent and selective V-ATPase inhibitors heretofore known were the bafilomycins and concanamycins, which do not discriminate between mammalian and nonmammalian V-ATPases. Numerous physiological processes are mediated by V-ATPases, and aberrant V-ATPase functions are implicated in many different human diseases. Previous efforts to develop therapeutic pharmacological modulators of V-ATPases have been frustrated by a lack of synthetically tractable and biologically selective leads. Therefore, availability of the unique benzolactone enamide inhibitor class may enable further elucidation of functional and architectural features of mammalian versus nonmammalian V-ATPase isoforms and provide new opportunities for targeting V-ATPase-mediated processes implicated in diverse pathophysiological phenomena, including cancer.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , ATPases Translocadoras de Prótons/antagonistas & inibidores , Vacúolos/enzimologia , Animais , Bovinos , Cães , Relação Dose-Resposta a Droga , Neurospora crassa/enzimologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
14.
Diabetes Care ; 24(2): 323-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11213886

RESUMO

OBJECTIVE: Cellular fibronectin is an endothelium-derived protein involved in subendothelial matrix assembly. Elevated plasma levels of cellular fibronectin therefore reflect loss of endothelial cell polarization or injury to blood vessels. Consequently, elevated plasma levels of circulating cellular fibronectin have been described in clinical syndromes with vascular damage, although not in diabetes or atherosclerosis. RESEARCH DESIGN AND METHODS: We determined fibronectin levels in 52 patients with type 1 diabetes, 50 patients with type 2 diabetes, 54 patients with a history of ischemic stroke, 23 patients with renal artery stenosis, and 64 healthy subjects. RESULTS: Circulating cellular fibronectin was significantly elevated in patients with diabetes (4.3 +/- 2.8 microg/ml) compared with patients with ischemic stroke (2.0 +/- 0.9 microg/ml), patients with renovascular hypertension (1.7 +/- 1.1 microg/ml), and healthy subjects (1.4 +/- 0.6 microg/ml). Patients with diabetes and at least one cardiovascular risk factor had an almost 2.5-fold increase in cellular fibronectin compared with diabetic subjects without such a risk factor. In multivariate regression analysis, higher triglycerides, current or past cigarette smoking, and higher urinary albumin excretion were independently associated with an increase in circulating cellular fibronectin in diabetes. CONCLUSIONS: These results suggest that circulating cellular fibronectin may be a marker protein for endothelial cell activation, especially in diabetes. Prospective studies are needed to explore this possibility


Assuntos
Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Fibronectinas/sangue , Adulto , Idoso , Albuminúria/sangue , Doenças Cardiovasculares/sangue , Endotélio Vascular/metabolismo , Feminino , Humanos , Hipertensão Renovascular/sangue , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Fumar , Acidente Vascular Cerebral/sangue , Triglicerídeos/sangue
15.
J Nat Prod ; 64(1): 88-91, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11170674

RESUMO

Further phytochemical analysis of the bulbs of Ornithogalum saundersiae has yielded two new cytotoxic cholestane triglycosides (1 and 2). The structures of these compounds were determined by spectroscopic analysis, including 2D NMR spectroscopic data, and the results of hydrolytic cleavage. Compounds 1 and 2 and several analogues were evaluated for their cytotoxicity against HL-60 cells.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Colestanos/isolamento & purificação , Glicosídeos/isolamento & purificação , Liliaceae/química , Raízes de Plantas/química , Plantas Medicinais/química , Antineoplásicos Fitogênicos/farmacologia , Colestanos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/farmacologia , Células HL-60 , Humanos , Hidrólise , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Células Tumorais Cultivadas
16.
J Nat Prod ; 63(10): 1411-3, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11076564

RESUMO

Two new 3,6-epidioxy-7,10-tetrahydrofurano C(26) unsaturated fatty acids, stolonic acids A (1) and B (2), were isolated from a previously undescribed ascidian species, Stolonica sp. collected off the Maldive Islands in the Indian Ocean. The structures and relative stereochemistry of 1 and 2 were determined using conventional spectroscopic methods. Both compounds exhibited antiproliferative activity against selected human melanoma and ovarian tumor cell lines, with IC(50) values of approximately 0.05-0.1 microg/mL.


Assuntos
Antineoplásicos/isolamento & purificação , Ácidos Graxos Insaturados/isolamento & purificação , Furanos/isolamento & purificação , Peróxidos/isolamento & purificação , Urocordados/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/farmacologia , Furanos/química , Furanos/farmacologia , Humanos , Oceano Índico , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Peróxidos/química , Peróxidos/farmacologia , Células Tumorais Cultivadas
17.
J Nucl Med ; 41(8): 1337-42, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10945524

RESUMO

UNLABELLED: Preliminary data suggest that aspirin renography is more sensitive than captopril renography for indicating renal artery stenosis (RAS). Considering that aspirin, compared with captopril, reduces renal blood flow and, thus, tubular tracer delivery in poststenotic kidneys, aspirin renography is expected to be more useful, particularly if tubular tracers are used. METHODS: We prospectively compared aspirin renography (20 mg/kg orally) and captopril renography (25 mg orally) with 99mTc-mercaptoacetyltriglycine in 75 consecutive patients suspected of having RAS. RESULTS: RAS, diagnosed as stenosis of more than 50% on angiography, was found unilaterally in 34 patients and bilaterally in 17 patients. RAS was absent in 24 patients. The sensitivities for unilateral RAS or bilateral RAS (i.e., stenosis that was at least unilateral) were, respectively, 88% and 88% for captopril renography and 82% and 94% for aspirin renography (not significant). The overall specificity was 75% for captopril renography and 83% for aspirin renography (not significant). Tracer uptake ratios, time to peak activity, and percentage of 20-min tracer retention were also not significantly different for captopril and aspirin renography. Subgroup analysis of modest (50-75%) and severe (> or =75%) RAS, or of plasma creatinine greater than 120 micromol/L, also showed no difference between captopril and aspirin renography. CONCLUSION: We conclude that for identification of RAS, the usefulness of aspirin renography equals, but does not surpass, that of captopril renography.


Assuntos
Aspirina , Captopril , Renografia por Radioisótopo/métodos , Compostos Radiofarmacêuticos , Obstrução da Artéria Renal/diagnóstico por imagem , Tecnécio Tc 99m Mertiatida , Idoso , Inibidores da Enzima Conversora de Angiotensina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tecnécio Tc 99m Mertiatida/farmacocinética
18.
Anticancer Drug Des ; 15(2): 79-98, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10901296

RESUMO

An analysis of the growth inhibitory potency of 122 anticancer agents available from the National Cancer Institute anticancer drug screen is presented. Methods of singular value decomposition (SVD) were applied to determine the matrix of distances between all compounds. These SVD-derived dissimilarity distances were used to cluster compounds that exhibit similar tumor growth inhibitory activity patterns against 60 human cancer cell lines. Cluster analysis divides the 122 standard agents into 25 statistically distinct groups. The first eight groups include structurally diverse compounds with reactive functionalities that act as DNA-damaging agents while the remaining 17 groups include compounds that inhibit nucleic acid biosynthesis and mitosis. Examination of the average activity patterns across the 60 tumor cell lines reveals unique 'fingerprints' associated with each group. A diverse set of structural features are observed for compounds within these groups, with frequent occurrences of strong within-group structural similarities. Clustering of cell types by their response to the 122 anticancer agents divides the 60 cell types into 21 groups. The strongest within-panel groupings were found for the renal, leukemia and ovarian cell panels. These results contribute to the basis for comparisons between log(GI(50)) screening patterns of the 122 anticancer agents and additional tested compounds.


Assuntos
Antineoplásicos/química , Antineoplásicos/toxicidade , Divisão Celular/efeitos dos fármacos , Animais , Antineoplásicos/classificação , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , National Institutes of Health (U.S.) , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Estados Unidos
19.
J Biomol Screen ; 5(3): 169-76, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10894760

RESUMO

The unique, high-affinity binding of cyanovirin-N (CV-N), a potent anti-human immunodeficiency virus (HIV) protein, to the HIV envelope glycoprotein gp120, was exploited to develop an HTS assay in an attempt to discover small-molecule mimetics of CV-N. A competition binding assay was developed using CV-N labeled with europium (Eu(3+)). The labeling protocol did not significantly alter the gp120 binding properties or the antiviral activity of CV-N. This report describes the assay development, validation, and results of screening a large library of aqueous and organic natural product extracts. The extracts were incubated with immobilized recombinant gp120 in 96-well plates prior to the addition of Eu(3+)-labeled CV-N. Following a wash step, bound CV-N was measured by dissociation-enhanced time-resolved fluorometry of Eu(3+). The assay proved to be robust, rapid, and reproducible, and was used to screen over 50,000 natural product extracts, and has resulted in the identification of several aqueous natural product extracts that inhibited CV-N-gp120 binding and also had anti-HIV activity.


Assuntos
Fármacos Anti-HIV/metabolismo , Proteínas de Bactérias , Fatores Biológicos/metabolismo , Proteínas de Transporte/metabolismo , Proteína gp120 do Envelope de HIV/metabolismo , HIV-1/metabolismo , Espectrometria de Fluorescência/métodos , Ligação Competitiva , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Humanos , Ligação Proteica , Proteínas Recombinantes/metabolismo
20.
J Nat Prod ; 63(5): 657-61, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10843580

RESUMO

Cytotoxicity-guided fractionation of the dichloromethane-methanol extract of the roots of Casearia arborea yielded five novel clerodane diterpenes, casearborins A-E (1-5), as well as cucurbitacin B. The presence of cucurbitacins glycosides was also detected. The absolute configuration of casearborin E was determined by X-ray crystallography.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Diterpenos/isolamento & purificação , Plantas Medicinais/química , Antineoplásicos Fitogênicos/farmacologia , Cromatografia Líquida de Alta Pressão , Cristalografia por Raios X , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Ultravioleta , Células Tumorais Cultivadas
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