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1.
J Palliat Care ; : 8258597221078391, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35129002

RESUMO

Background and Objectives: Immune checkpoint inhibitors (ICIs) have less toxicity than standard chemotherapy and are now standard of care for many patients with advanced cancer. A manageable side effect profile and potential for durable responses may lead to aggressive care of the palliative patient. We sought to evaluate palliative care input and ICI use at the end of life at two Irish cancer centres. Methods: We identified deceased patients who received at least one dose of an ICI between first of January 2013 to 31st of December 2018. A retrospective electronic chart review was performed. Results: The electronic records of 102 patients were analysed. Fifty eight percent were male and the median age of diagnosis of advanced disease was 60 years (range 17-78). Median time from last dose of ICI to death was 57 days (range 8-574) and 20% of patients died within 30 days of last dose of ICI. Most patients, 92%, were referred to palliative care. The median time from palliative care referral to death was 64 days (range 1- 1010). In the last 30 days of life, 39% of patients attended the emergency department (ED) and 46% had at least one hospital admission. Late palliative care referrals, ≤3 months before death, were associated with hospitalisations in the last month of life (64% vs. 36%, P = .02). Timing of palliative care referral did not affect ICI prescribing at the end of life (P = 0.38). ICI use in the last 30 days of life was not associated with increased ED presentations or hospitalisations at the end of life. Patients who received ICI in the last month had a higher likelihood of in-hospital death (43% vs. 16%, P = 0.02). Conclusions: ICI within 30 days of death was associated with dying in hospital but did not lead to more hospitalisations and emergency department presentations. Early palliative care did not affect ICI use but reduced hospitalisations at the end of life.

2.
Cancer Treat Rev ; 98: 102225, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34082256

RESUMO

It is estimated that 604,127 patients were diagnosed with cervical cancer worldwide in 2020. While a small percentage of patients will have metastatic disease at diagnosis, a large percentage (15-61%) later develop advanced disease. For this cohort, treatment with systemic chemotherapy remains the standard of care, with a static 5-year survival rate over the last thirty years. Data on targetable molecular alterations in cervical cancer have lagged behind other more common tumor types thus stunting the development of targeted agents. In recent years, tumor genomic testing has been increasingly incorporated into our clinical practice, opening the door for a potential new era of personalized treatment for advanced cervical cancer. The interim results from the NCI-MATCH study reported an actionability rate of 28.4% for the cervical cancer cohort, suggesting a subset of patients may harbor mutations which that are targetable. This review sets out to summarize the key targeted agents currently under exploration either alone or in combination with existing treatments for cervical cancer.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Terapia de Alvo Molecular , Mutação , Medicina de Precisão , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Biomarcadores Tumorais/antagonistas & inibidores , Feminino , Humanos , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/secundário
3.
Ir J Med Sci ; 186(1): 81-87, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27498210

RESUMO

BACKGROUND: There is extensive focus on the rising costs of healthcare. However, for patients undergoing cancer treatment, there are additional personal costs, which are poorly characterised. AIM: To qualify indirect costs during anti-cancer therapy in a designated Irish cancer centre. METHODS: An anonymous questionnaire collected demographic data, current work practice, and personal expenditure on regular and non-regular indirect costs during treatment. Differences between groups of interest were compared using the Mann-Whitney U test. RESULTS: In total, there were 151 responders of median age 58 years; 60 % were female and 74 % were not working. Breast cancer (29 %) was the most frequent diagnosis. Indirect costs totalled a median of €1138 (range €21.60-€7089.84) per patient, with median monthly outgoings of €354. The greatest median monthly costs were hair accessories (€400), transportation (€65), and complementary therapies (€55). The majority (74 %) of patients used a car and median monthly fuel expenditure was €31 (range €1.44-€463.32). Women spent more money during treatment (€1617) than men (€974, p = 0.00128). In addition, median monthly expenditure was greater for those less than 50 years old (€1621 vs €1105; p = 0.04236), those who lived greater than 25 km away (€2015 vs €1078; p = 0.00008) and those without a medical card (€2023 vs €961; p = 0.00024). CONCLUSION: This study highlights the need for greater awareness of indirect expenditures associated with systemic anti-cancer therapy in Ireland.


Assuntos
Assistência Ambulatorial/economia , Custos de Cuidados de Saúde , Neoplasias/terapia , Adulto , Idoso , Neoplasias da Mama/economia , Neoplasias da Mama/terapia , Custos e Análise de Custo , Atenção à Saúde , Feminino , Gastos em Saúde , Humanos , Irlanda , Masculino , Pessoa de Meia-Idade , Neoplasias/economia , Pacientes Ambulatoriais , Inquéritos e Questionários , Adulto Jovem
4.
Oncogene ; 34(4): 525-30, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-24469058

RESUMO

Treatment with tyrosine kinase inhibitors (TKIs) including trastuzumab has revolutionized the management of HER2-positive breast cancer. Recent evaluation of clinical trial data suggests that a subset of HER2/ER double-positive cancers may not receive significant benefit from the TKI therapy. Here we investigate the cross talk between HER2 and ER in breast cancer and monitor the effect of trastuzumab on the tyrosine kinase effector transcription factor Myc. In HER2-positive breast cancer patients treated with neoadjuvant trastuzumab, steroid receptor-negative status (ER and PR negative) of pre-treatment biopsies predicted pathological complete response (pCR) (n=31 patients, P=0.0486), whereas elevated Myc protein inversely associated with pCR (P=0.0446). Liquid chromatography mass spectrometry identified the corepressor SMRT as a novel Myc-interacting protein. Trastuzumab treatment enhanced Myc-SMRT interactions in HER2-overexpressing breast cancer cells (LCC1) and inhibited expression of the Myc target gene survivin. In HER2-low, ER-positive steroid-dominant cells (MCF7), trastuzumab therapy repressed Myc-SMRT interactions and upregulated survivin expression. Trastuzumab treatment induced ER-CBP interactions, enhanced ER transcriptional activity and upregulated expression of the ER target gene pS2. The absence of pS2 expression in pre-treatment biopsies predicted pCR to neoadjuvant trastuzumab in breast cancer patients (n=25, P=0.0089) and pS2 expression associated with residual cancer burden (P=0.0196). Furthermore, metastatic tissues from patients who had failed trastuzumab therapy were pS2 positive. In HER2-overexpressing cells, trastuzumab treatment can repress Myc transcriptional activity and clinical response is favorable. However, with co-expression of the steroid pathway, this inhibition is lost and response to treatment is often poor.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Receptor Cross-Talk/fisiologia , Receptor ErbB-2/fisiologia , Receptores de Estrogênio/fisiologia , Neoplasias da Mama/química , Feminino , Humanos , Células MCF-7 , Correpressor 2 de Receptor Nuclear/fisiologia , Proteínas Proto-Oncogênicas c-myc/fisiologia , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Trastuzumab , Fator Trefoil-1 , Proteínas Supressoras de Tumor/análise
5.
J Anim Sci ; 83(10): 2372-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16160049

RESUMO

Because the poor growth performance of intensively housed pigs is associated with increased circulating glucocorticoid concentrations, we investigated the effects of glucocorticoid suppression by inducing a humoral immune response to ACTH on physiological and production variables in growing pigs. Grower pigs (28.6 +/- 0.9 kg) were immunized with amino acids 1 through 24 of ACTH conjugated to ovalbumin and suspended in diethylaminoethyl (DEAE) dextran-adjuvant or adjuvant alone (control) on d 1, 28, and 56. The ACTH-specific antibody titers generated suppressed increases in cortisol concentrations on d 63 in response to an acute stressor (P = 0.002; control = 71 +/- 8.2 ng/mL; ACTH-immune = 43 +/- 4.9 ng/mL) without altering basal concentrations. Plasma beta-endorphin concentrations were also increased (P < 0.001) on d 63 (control = 18 +/- 2.1 ng/mL; ACTH-immune = 63 +/- 7.3 ng/mL), presumably because of a release from negative feedback on the expression of proopiomelanocortin in pituitary corticotropes. Immunization against ACTH did not alter ADG (P = 0.120; control = 1,077 +/- 25; ACTH-immune = 1,143 +/- 25 g) or ADFI (P = 0.64; control = 2,719 +/- 42; ACTH-immune = 2,749 +/- 42 g) and did not modify behavior (P = 0.681) assessed by measuring vocalization in response to acute restraint. In summary, suppression of stress-induced cortisol responses through ACTH immunization increased beta-endorphin concentrations, but it did not modify ADG, ADFI, or restraint vocalization score in growing pigs.


Assuntos
Hormônio Adrenocorticotrópico/imunologia , Hidrocortisona/sangue , Suínos/fisiologia , Vocalização Animal/fisiologia , beta-Endorfina/sangue , Análise de Variância , Animais , Anticorpos/sangue , Ingestão de Alimentos/fisiologia , Abrigo para Animais , Imunização/veterinária , Masculino , Densidade Demográfica , Distribuição Aleatória , Suínos/sangue , Suínos/crescimento & desenvolvimento , Suínos/imunologia , Fatores de Tempo , Aumento de Peso/fisiologia
6.
Anal Bioanal Chem ; 372(1): 66-73, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11939214

RESUMO

Ion mobility spectrometry (IMS) has been used for over 30 years as a sensitive detector of organic compounds. The following is a brief review of IMS and its principles with an emphasis on its usage when coupled to mass spectrometry. Since its inception, IMS has been interfaced with quadrupole, time-of-flight, and Fourier-transform ion cyclotron resonance mass spectrometry. These hybrid instruments have been employed for the analysis of a variety of target analytes, including biomolecules, explosives, chemical warfare degradation products, and illicit drugs.

7.
Health Place ; 7(4): 293-306, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11682329

RESUMO

In this paper, we discuss recent efforts to improve the safety of children travelling to and from New Zealand's largest primary school. The results of a travel survey completed by parents and pupils are reported, together with our recommendations for reducing congestion at the school gate and promoting healthy alternatives to car travel. Reflecting on this research, we find that market-oriented education reforms have provided schools with strong incentives for increasing their rolls--a course of action which may endanger pupils' well-being. At the same time, they have provided some schools with opportunities for resisting the present urban (dis)order and promoting community health.


Assuntos
Proteção da Criança , Planejamento de Cidades , Segurança/normas , Instituições Acadêmicas/normas , Acidentes de Trânsito , Criança , Pré-Escolar , Relações Comunidade-Instituição , Humanos , Entrevistas como Assunto , Motivação , Nova Zelândia , Pais , Medição de Risco , Segurança/estatística & dados numéricos , Instituições Acadêmicas/organização & administração , Fatores de Tempo , Meios de Transporte/métodos , Meios de Transporte/normas , Estados Unidos , Violência
8.
J Steroid Biochem Mol Biol ; 77(2-3): 177-82, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11377984

RESUMO

We have investigated the roles of highly conserved glycine (G175, G185), negatively charged (E188, D165) and histidine residues (H233, H237) in rat steroid 5alpha-reductase (isozyme-1), on NADPH, testosterone (T) binding and enzyme activity. The mutations G175R and G175S result in a two- to threefold increase in K(m)(NADPH) and an approximately fourfold decrease in the V(max) with no change in K(m)(T). The mutation G185W resulted in a fivefold decrease in K(m)(NADPH) and an eightfold decrease in V(max), with no change in K(m)(T), whereas the mutations E188Q and D165N both resulted in inactive enzyme. Steady-state kinetic measurements showed that the mutation H233R resulted in an approximately 40-fold decrease in V(max), an approximately 20-fold increase in K(m)(T) and no alteration in K(m)(NADPH), whereas the mutation H237R resulted in virtually inactive enzyme. The results suggest that the conserved glycines are not essential for cofactor binding and activity, and that the negatively charged residues may contribute to enzyme stability, whereas the C-terminal histidines appear to be involved in substrate binding and catalytic activity.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Isoenzimas/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/química , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Sequência de Aminoácidos , Animais , Isoenzimas/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica , Ratos
9.
Fresenius J Anal Chem ; 369(3-4): 225-33, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11293698

RESUMO

A moderately high resolution nanoelectrospray ionization gas-phase electrophoresis instrument was constructed and evaluated for simple high-speed separations of several groups of compounds. The insertion of a plate containing a 1.6 cm diameter exit orifice, 2.5 cm from the location of electrospray, allowed ions to be created and desolvated under ambient conditions with minimal solvent contamination to the drift tube. Ion separation selectivity is discussed and shown to be slightly altered by changing the drift gas flow rate. Issues of using gas-phase electrophoresis as a high-speed separation technique are discussed. Gas-phase electrophoresis-spectra of selected benzodiazepines, triazine herbicides, and simple combinatorial chemistry libraries are demonstrated.


Assuntos
Ansiolíticos/análise , Eletroforese/métodos , Herbicidas/análise , Alprazolam/análise , Técnicas de Química Combinatória , Diazepam/análise , Eletroforese/instrumentação , Desenho de Equipamento , Nitrazepam/análise , Oxazepam/análise , Prazepam/análise , Fatores de Tempo , Triazinas/análise
10.
Soc Sci Med ; 51(7): 1047-59, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11005392

RESUMO

This paper surveys the history and current status of children's health camps in New Zealand, and places these sites within the theoretical context of therapeutic landscapes. The first health camp was established in 1919, and the seven current camps provide respite, education and health care for approximately 4000 children each year. We analyse the health-place relations inherent in the health camp concept and suggest that the 'therapeutic landscape' idea developed by Gesler provides a useful framework to explain the development of camps as sites for enhancing child and family welfare. Specifically, we contend that changing understandings of health and children have been closely linked with changing perceptions of what is therapeutic about the camps. Survey data demonstrate that contemporary restructuring of the welfare state has recast the role of health camps and placed them in a precarious position in terms of both financial viability and public acceptability. We conclude that the current status of health camps is ambiguous given the pressures of deinstitutionalisation philosophies and the regulatory environment of formal contracts between funders and providers.


Assuntos
Serviços de Saúde da Criança/organização & administração , Estâncias para Tratamento de Saúde , Criança , Desinstitucionalização , Apoio Financeiro , Humanos , Relações Interinstitucionais , Nova Zelândia
11.
J Clin Endocrinol Metab ; 84(9): 3217-21, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10487690

RESUMO

This study compared the enzyme activity of 3alpha-hydroxysteroid dehydrogenase (3alphaHSD) and 3beta-hydroxysteroid dehydrogenase (3betaHSD) in the human liver. 3AlphaHSD was found in both microsomal and cytosolic liver fractions. Contrary to that in rat liver, microsomal 3alphaHSD activity was 12-fold higher than cytosolic 3alphaHSD activity, and 3alphaHSD was not inhibited by indomethacin (10 micromol/L). The rate of 5alpha-dihydrotestosterone (DHT) reduction to 5alpha-androstane-3alpha,17beta-diol (3alphaDIOL) by 3alphaHSD was 2 times higher than the rate of 3alphaDIOL oxidation to DHT. 3BetaHSD was present primarily in the microsomal fraction of the human liver, and the rate of DHT reduction to 5alpha-androstane-3beta,17beta-diol (3betaDIOL) by 3betaHSD was 3 times higher than the rate of 3betaHSD oxidation to DHT. When 3alphaHSD and 3betaHSD activities were compared, the rate of DHT reduction by 3betaHSD was 3-fold lower than the rate of DHT reduction by 3alphaHSD. No sex or age differences were found in either 3alphaHSD or 3betaHSD activity. As the activity of DHT-metabolizing enzymes is not sex dependent, the sex differences in plasma levels of 3alphaDIOL glucuronide probably reflect differences in DHT production rather than in DHT metabolism. Comparison of the activities of 3alphaHSD, 3betaHSD, and androgen UDP-glucuronyl transferase suggests that the major pathway of DHT metabolism in human liver involves 3alphaHSD reduction in the liver, followed by subsequent glucuronidation and clearance via the kidney.


Assuntos
3-Hidroxiesteroide Desidrogenases/metabolismo , Di-Hidrotestosterona/metabolismo , Fígado/metabolismo , 3-alfa-Hidroxiesteroide Desidrogenase (B-Específica) , Adulto , Idoso , Androstano-3,17-diol/metabolismo , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Valores de Referência , Caracteres Sexuais
12.
Steroids ; 64(3): 197-204, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10400380

RESUMO

We have previously shown that the photoactive 4-azasteroid, [1,2 3H]N-4(benzylbenzoyl)-3-oxo-4-aza-4-methyl-5alpha-androst an-17beta-carboxamide is an effective probe of rat steroid 5alpha-reductase (isozyme-1) (5alphaR-1). In the current investigation, PEG-fractionated (6.5%) detergent-solubilized preparations containing 5alphaR-1 activity were ultraviolet (UV)-photolyzed with [3H]-4MABP and subsequently purified by 8.75% preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The fractions corresponding to the radioactive peak following the dye front were analyzed by 10% sodium dodecyl sulfate-polyacrylamide gel electrophoresis and showed the presence of a single, labeled, 26 KDa protein band, the apparent molecular weight of 5alphaR-1. TCA precipitation of the labeled fractions, followed by long-term digestion of the TCA pellet with chymotrypsin and high-performance liquid chromatography analysis, indicated that the majority of the radioactivity eluted with a peak retention time of 55-56 min. Rechromatography of this fraction using a modified gradient (elution 54-55 min), followed by sequence analysis, yielded a single N-terminal tetrapeptide with the sequence, -L-E-G-F-, corresponding to residues 15-18 of the 5alphaR-1 sequence. Site-directed mutagenesis studies indicated that mutant F18L showed an approximately 12-fold increase in the Km for testosterone, whereas the Km for reduced nicotinomide adenine dinucleotide phosphate remained virtually unaltered.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Esteroides/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/química , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Sequência de Aminoácidos , Androstanos/química , Animais , Azasteroides/química , Sequência de Bases , Sítios de Ligação , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Cinética , Sondas Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Ratos , Ratos Sprague-Dawley
13.
Steroids ; 64(5): 356-62, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10406485

RESUMO

Previous studies have shown that the reduced nicotinamide adenine dinucleotide phosphate (NADPH)- binding domain of rat liver microsomal steroid 5alpha-reductase isozyme-1 (r5alphaR-1) is in a highly conserved region of the polypeptide sequence (residues 160-190). In this study, we investigated, by site-directed mutagenesis, the role of hydroxylated and aromatic amino acids within the NADPH-binding domain. The r5alphaR-1 cDNA was cloned into a pCMV vector, and the double strand site-directed mutagenesis method was used to create mutants Y179F, Y179S, Y189F, Y189S, S164A, S164T, and Y187F, which were subsequently expressed in COS-1 cells. Kinetic studies of the expressed enzymes showed that the mutation Y179F resulted in an approximately 40-fold increase in the Km for NADPH versus wild-type, with only a 2-fold increase in the Km for testosterone. The mutants Y189F and S164A showed smaller increases (4 and 6-fold) in Kms for NADPH and no significant change in the Km for testosterone, whereas Y189S had kinetic properties similar to the wild-type r5alphaR-1. Mutants Y179S and S164T both resulted in inactive enzymes, whereas F187Y showed an approximately 5-fold decrease in Km for NADPH and a significant increase (approximately 18-fold) in the Km for testosterone. The results suggest that the -OH functionality of Y179 is involved in cofactor binding, but is not essential for the activity of the enzyme, whereas the -OH functionalities of Y189 and S164 play lesser roles in cofactor binding to r5alphaR-1 and may not be required for enzyme activity. On the other hand, the residue F187 may be important for the binding of both NADPH and testosterone.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Aminoácidos/análise , Isoenzimas/genética , Mutagênese Sítio-Dirigida , NADP/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/química , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Western Blotting , Células COS , Hidroxilação , Isoenzimas/química , Isoenzimas/metabolismo , Cinética , Dados de Sequência Molecular , Mutação Puntual , Ratos , Alinhamento de Sequência , Relação Estrutura-Atividade
15.
Anticancer Res ; 19(5B): 4023-5, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10628348

RESUMO

Lectins have been used extensively as histochemical probes to describe changes in tumor cell surface and are known to influence the growth of cancer cells. In this study, we determined the effect of a lectin from the venom of Bothrops jararacussu (BJcuL) on the proliferation of a number of established human cancer cell lines. The growth of eight cancer cell lines was inhibited in a dose-related manner in the presence of BJcuL lectin. This lectin was most potent as an inhibitor of growth in renal (Caki-1 and A-498) and pancreatic (CFPAC-1) cancer cell lines with 50% inhibitory concentrations (IC50) of 1-2 mM. Melanoma (Wm115) and prostate (PC-3) cancer cells showed IC50 values of 7.9 and 8.5 mM, respectively, in the presence of BjcuL lectin whereas colon (Caco-2) and breast (MCF7) cancer cell lines showed no effect. Our results suggest that BJcuL lectin is an effective inhibitor of cell growth in some cancer cell lines.


Assuntos
Venenos de Crotalídeos , Lectinas/farmacologia , Neoplasias da Mama/patologia , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Concentração Inibidora 50 , Neoplasias Renais/patologia , Masculino , Melanoma/patologia , Neoplasias Pancreáticas/patologia , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas
16.
Cancer Lett ; 125(1-2): 97-102, 1998 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-9566702

RESUMO

We have demonstrated for the first time that suramin is taken up by human dermal microvascular endothelial (HMEC-1) cells by an active process involving the caveolae system. The uptake of suramin was time-dependent and reduced by more than 90% when incubated in the presence of albumin or at 4 degrees C. Suramin uptake was also inhibited when incubated in the presence of filipin and digitonin, both potent cholesterol-binding agents, but not in the presence of probenecid. The [3H]suramin taken up by the HMEC-1 cells was located primarily within the nucleus, followed by the cytoplasmic fraction. The presence of suramin in these cellular compartments suggests that this drug may act through intracellular mechanisms.


Assuntos
Antineoplásicos/farmacocinética , Endotélio Vascular/metabolismo , Suramina/farmacocinética , Células Cultivadas , Humanos , Albumina Sérica/farmacologia
18.
Cancer Chemother Pharmacol ; 41(2): 117-24, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9443624

RESUMO

The purpose of this study was to test the ability of 70 polyanionic analogues of suramin to inhibit angiogenesis. The ID50, the dose that produced 50% inhibition of angiogenesis, was determined for suramin and each of the analogues by measuring the ability of various amounts to inhibit angiogenesis in vivo in the chick egg chorioallantoic membrane (CAM) assay. Of the 70 analogues, 11 had antiangiogenic activities similar to suramin and an additional 7 were significantly more potent than suramin. All seven of these analogues were from the naphthalenetrisulfonic acid group and contained large urea groups. The benzene sulfonic and disulfonic acid analogues were less active inhibitors of angiogenesis than the naphthalenetrisulfonic acid analogues. Replacement of the naphthalenetrisulfonic acid groups by aliphatic carboxylic acids or benzoic acid gave analogues with very little antiangiogenic activity. In subsequent experiments, the antiproliferative activity of selected analogues on basic FGF (bFGF)-stimulated growth of immortalized human microvascular endothelial cells in vitro was determined. Analogues that inhibited angiogenesis to a greater extent than suramin in the CAM assay generally showed a greater antiproliferative effect on bFGF-induced growth of human microvascular endothelial cells. These results suggest that some of the polyanionic analogues may be potent therapeutic agents for cancers and angiogenesis-dependent diseases.


Assuntos
Antineoplásicos/farmacologia , Endotélio Vascular/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Suramina/análogos & derivados , Animais , Divisão Celular/efeitos dos fármacos , Embrião de Galinha , Humanos , Relação Estrutura-Atividade , Suramina/farmacologia
19.
Steroids ; 62(4): 373-8, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9090798

RESUMO

The enzyme steroid 5 alpha-reductase (5 alpha R) catalyzes the reduction of testosterone (T) to 5 alpha-dihydrotestosterone (DHT). In this study, the baculovirus expression system was used to overexpress rat 5 alpha R type I isozyme (r5 alpha R 1). The full length of r5 alpha R1 cDNA was inserted into the Autographa californica nuclear polyhedrosis virus (Ac-MNPV) genome and expressed in Spodoptera frugiperda, Sf 21, insect cells. The expressed recombinant r5 alpha-R1 showed maximal enzymatic activity when the infected cells were harvested on day 3 of post-transfection. The K(m) values for NADPH and T were 17 microM and 2.7 microM, respectively. Inhibition of the recombinant r5 alpha R1 by N,N diethyl-4-aza-4-methyl-3-oxo-5 alpha-androstane-17 beta-carboxamide (4MA) was competitive with respect to the substrate (T), and a Ki of 3 nM was obtained. The enzyme was located primarily in the nuclear fraction, and the maximum velocity for the recombinant r5 alpha R1 in this fraction was 60 nmoles DHT/min/mg. Immunoblot analysis indicated a single immunoreactive band at 26 kDa, which corresponds to the molecular weight of r5 alpha R1. Photoaffinity labeling by [2'-32P]-2-azido-NAD P+ ([2'-32P]2N3-NAD P+) and [1,2(3)H] N-(benzylbenzoyl)-3-oxo-4-aza-4-methyl-5 alpha androstane-17 beta-carboxamide ([3H]-4MABP) also showed a labeled protein band at 26 kDa.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Marcadores de Afinidade/metabolismo , Androstanos/metabolismo , Animais , Azasteroides/metabolismo , Azidas/metabolismo , Clonagem Molecular , Cinética , NADP/análogos & derivados , NADP/metabolismo , Nucleopoliedrovírus , Ratos , Spodoptera , Testosterona/metabolismo , Transfecção
20.
J Androl ; 18(2): 116-22, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9154505

RESUMO

In this study, androgen UDP-glucuronyl transferase (UDPGT) activity was determined in microsomes of human liver, skin, and prostate. Androgen UDPGT activity was highest in the liver microsomes using 5 alpha-androstane-3 alpha, 17 beta-diol (3 alpha DIOL), androsterone (AN) and dihydrotestosterone (DHT) as substrates. The Km and Vmax values and enzyme velocity at the physiological concentration of the substrates in the liver microsomes were similar for AN and 3 alpha DIOL. The values for AN were as follows: Km = 16.9 microM, Vmax = 3.77 nmol/min/mg protein, and UDPGT velocity = 0.62 pmol/min/mg protein. The values for 3 alpha DIOL were as follows: Km = 16.0 microM, Vmax = 5.61 nmol/min/mg protein, and UDPGT velocity = 0.42 pmol/min/mg protein. Androgen UDPGT activity was lower and showed less affinity for DHT (Km = 23.5 microM, Vmax = 0.84 nmol/min/mg protein, UDPGT velocity = 0.05 pmol/min/mg protein). No sex or age differences in 3 alpha DIOL-UDPGT activity were found in liver microsomes. The kinetic parameters and levels of androgen UDPGT activity in the skin and prostate samples were not determined because the levels of UDPGT activity were below the detection limit for our assay (0.003 pmol/min/mg protein). These results have important clinical implications. First, androgen UDPGT activity in the skin and prostate is much lower than the activity in the liver, suggesting that these tissues are not important sites for conjugation of androgens. Second, androgen UDPGT activity in the liver was not altered by sex or age in the 10 samples measured from men and women.


Assuntos
Glucuronosiltransferase/metabolismo , Fígado/enzimologia , Microssomos Hepáticos/enzimologia , Adulto , Idoso , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos , Próstata/enzimologia , Caracteres Sexuais , Pele/enzimologia , Especificidade por Substrato
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