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1.
BMC Public Health ; 21(1): 1496, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344340

RESUMO

BACKGROUND: The BETTER (Building on Existing Tools to Improve Chronic Disease Prevention and Screening in Primary Care) intervention was designed to integrate the approach to chronic disease prevention and screening in primary care and demonstrated effective in a previous randomized trial. METHODS: We tested the effectiveness of the BETTER HEALTH intervention, a public health adaptation of BETTER, at improving participation in chronic disease prevention and screening actions for residents of low-income neighbourhoods in a cluster randomized trial, with ten low-income neighbourhoods in Durham Region Ontario randomized to immediate intervention vs. wait-list. The unit of analysis was the individual, and eligible participants were adults age 40-64 years residing in the neighbourhoods. Public health nurses trained as "prevention practitioners" held one prevention-focused visit with each participant. They provided participants with a tailored prevention prescription and supported them to set health-related goals. The primary outcome was a composite index: the number of evidence-based actions achieved at six months as a proportion of those for which participants were eligible at baseline. RESULTS: Of 126 participants (60 in immediate arm; 66 in wait-list arm), 125 were included in analyses (1 participant withdrew consent). In both arms, participants were eligible for a mean of 8.6 actions at baseline. At follow-up, participants in the immediate intervention arm met 64.5% of actions for which they were eligible versus 42.1% in the wait-list arm (rate ratio 1.53 [95% confidence interval 1.22-1.84]). CONCLUSION: Public health nurses using the BETTER HEALTH intervention led to a higher proportion of identified evidence-based prevention and screening actions achieved at six months for people living with socioeconomic disadvantage. TRIAL REGISTRATION: NCT03052959 , registered February 10, 2017.


Assuntos
Programas de Rastreamento , Saúde Pública , Adulto , Doença Crônica , Humanos , Pessoa de Meia-Idade , Ontário , Atenção Primária à Saúde
2.
Pediatr Blood Cancer ; 65(3)2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29115718

RESUMO

BACKGROUND: Young children with posterior fossa ependymoma (PF-EPN) have a worse prognosis than older children, and they have a unique molecular profile (PF-EPN-A subtype). Alternative treatment strategies are often used in these young patients, and their prognostic factors are less clear. METHODS: We characterized the prognostic factors and treatment outcomes of 482 patients between ages 0 and 3 years with the diagnosis of ependymoma identified from the Surveillance, Epidemiology, and End Results registry (1973-2013). RESULTS: Radiation therapy (RT) was delivered to 52.3% of patients, and gross total resection (GTR) was performed in 51.0% of patients. Overall survival (OS) at 10 years was 48.4% with median follow-up of 3.3 years. WHO grade was not predictive of OS. Extent of resection was significant for survival; the 10-year OS with GTR was 61.0%, and with subtotal resection (STR) and biopsy was 38.2% and 35.0%, respectively (P < 0.001). RT significantly benefitted OS for both grades II and III. The 10-year OS for grade II was 50.5% with RT and 43.4% without (P = 0.030); 10-year OS for grade III was 66.0% with RT and 40.0% without (P = 0.002). Multivariate analysis showed significantly improved OS with RT (hazard ratio [HR] 0.601, 95% CI: 0.439-0.820, P = 0.001) and GTR (HR 0.471, 95% CI: 0.328-0.677, P < 0.0001). CONCLUSIONS: Ependymoma outcomes in patients within 0-3 years of age significantly improved with RT and GTR. Histopathologic grading of ependymoma demonstrated no prognostic significance. Given the poor OS for this population and unique genetic profile, future prospective studies with molecular-based stratification should be performed to evaluate additional prognostic factors.


Assuntos
Ependimoma/radioterapia , Ependimoma/cirurgia , Neoplasias Infratentoriais/radioterapia , Neoplasias Infratentoriais/cirurgia , Pré-Escolar , Ependimoma/mortalidade , Feminino , Humanos , Lactente , Recém-Nascido , Neoplasias Infratentoriais/mortalidade , Masculino , Prognóstico , Intervalo Livre de Progressão , Programa de SEER , Resultado do Tratamento
3.
J Med Primatol ; 33(4): 197-213, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15271069

RESUMO

Over 23 months, zinc toxicosis was diagnosed in 35 baboons aged 5-12 months in one galvanized metal and concrete cage complex with conditions that led to excessive exposure to environmental zinc. Clinical signs included reduced pigmentation of hair, skin, and mucous membranes (whiteness), alopecia, dehydration, emaciation, cachexia, dermatitis, diarrhea and, in six cases, severe gangrenous dermatitis of extremities. The syndrome was characterized by pancytopenia, elevated zinc and low copper serum concentrations, low vitamin D and bone-specific alkaline phosphatase levels, and atypical myelomonocytic proliferation of bone marrow. This syndrome emphasizes the importance of proper husbandry and cage design and indicates the potential of infant baboons as a model to study the effects of excessive zinc on development. This is the first report describing the epidemiologic and clinical presentation of zinc toxicosis in infant baboons in captivity.


Assuntos
Exposição Ambiental , Abrigo para Animais , Doenças dos Macacos/patologia , Papio , Vitamina D/análogos & derivados , Zinco/intoxicação , Alopecia/etiologia , Alopecia/veterinária , Análise de Variância , Anemia/etiologia , Anemia/veterinária , Animais , Osso e Ossos/diagnóstico por imagem , Cobre/sangue , Cobre/deficiência , Proteínas de Ligação a DNA/sangue , Dermatite/etiologia , Dermatite/veterinária , Diarreia/etiologia , Diarreia/veterinária , Citometria de Fluxo/veterinária , Cariotipagem/veterinária , Luz , Fator de Transcrição PAX5 , Pigmentação/efeitos dos fármacos , Radiografia , Radioimunoensaio/veterinária , Síndrome , Fatores de Transcrição/sangue , Vitamina D/sangue , Zinco/sangue
4.
Crit Care Med ; 25(7): 1198-206, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9233748

RESUMO

OBJECTIVE: Proinflammatory eicosanoids and cytokines are important mediators of local inflammation in acute lung injury. We determined if enteral nutrition with anti-inflammatory fatty acids, eicosapentaenoic acid, and gamma-linolenic acid would reduce the intrapulmonary synthesis of proinflammatory eicosanoids and cytokines and pulmonary neutrophil accumulation in a rat model of acute lung injury. DESIGN: Prospective, randomized, controlled, double-blind study. SETTING: Research laboratory at a university medical center. SUBJECTS: Male Long-Evans rats (250 g). INTERVENTIONS: Rats were randomly assigned to three dietary treatment groups and fed nutritionally complete diets (300 kcal/kg/day) containing 55.2% of the total calories from fat with either 97% corn oil, 20% fish oil, or 20% fish and 20% borage oil for 21 days. On day 22, bronchoalveolar lavage was performed 2 hrs after an intravenous injection of Salmonella enteritidis endotoxin (10 mg/kg) or saline. Bronchoalveolar lavage fluid was analyzed for leukotriene B4, leukotriene C4/D4, thromboxane B2, prostaglandin E2, 6 keto-prostaglandin F1alpha, tumor necrosis factor (TNF)-alpha, and macrophage inflammatory protein-2 (MIP-2). Lung myeloperoxidase activity (a marker for neutrophil accumulation) and phospholipid fatty acid composition were also determined. MEASUREMENTS AND MAIN RESULTS: Lung phospholipid concentrations of arachidonic acid were lower and the concentrations of eicosapentaenoic acid and docosahexaenoic acid were higher with fish oil and fish and borage oil as compared with corn oil. Dihomo-gamma-linolenic acid, the desaturated and elongated intermediate of gamma-linolenic acid, increased with fish and borage oil as compared with fish oil and corn oil. The levels of leukotriene B4, leukotriene C4/D4, 6-keto-prostaglandin F1alpha, and thromboxane B2 with corn oil were significantly increased with endotoxin as compared with saline. In contrast to the corn oil group, endotoxin did not significantly increase bronchoalveolar lavage levels of leukotriene B4, leukotriene C4/D4, and thromboxane B2 above those of saline-treated rats with fish oil and fish and borage oil. Lung myeloperoxidase activity was significantly increased in endotoxin-treated rats compared with those rats given saline in all dietary treatment groups. However, lung myeloperoxidase activity was significantly lower with either fish oil or fish and borage oil as compared with corn oil after endotoxin. Although endotoxin increased the levels of TNF-alpha and MIP-2 with all dietary treatment groups as compared with saline-treated rats, there were no significant differences in the levels of either cytokine between the dietary treatment groups. CONCLUSIONS: These results indicate that dietary fish oil and fish and borage oil as compared with corn oil may ameliorate endotoxin-induced acute lung injury by suppressing the levels of proinflammatory eicosanoids (but not TNF-alpha or MIP-2) in bronchoalveolar lavage fluid and reducing pulmonary neutrophil accumulation.


Assuntos
Eicosanoides/biossíntese , Endotoxemia/terapia , Óleos de Peixe/farmacologia , Pneumopatias/fisiopatologia , Neutrófilos/fisiologia , Óleos de Plantas/farmacologia , Animais , Líquido da Lavagem Broncoalveolar , Citocinas/metabolismo , Gorduras Insaturadas na Dieta/farmacologia , Método Duplo-Cego , Ácido Eicosapentaenoico/farmacologia , Endotoxemia/fisiopatologia , Estudos de Avaliação como Assunto , Pneumopatias/etiologia , Pneumopatias/prevenção & controle , Masculino , Peroxidase/metabolismo , Fosfolipídeos/metabolismo , Estudos Prospectivos , Distribuição Aleatória , Ratos , Ácido gama-Linolênico/farmacologia
5.
J Surg Res ; 68(1): 16-23, 1997 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9126190

RESUMO

OBJECTIVE: To determine if cytokine responses and lung injury induced by intravenous (i.v.) lipopolysaccharide (LPS) at 4 hr were enhanced in rats that had been previously subjected to 30 min of total liver ischemia (Pringle's maneuver) followed by 24 hr or 3 days of reperfusion. BACKGROUND: Many patients with liver trauma require occlusion of hepatic blood flow to control hemorrhage and facilitate repair. A significant number of these patients subsequently develop the systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction (MOD) characterized by the release of cytokines and tissue neutrophil influx. Macrophages, including Kupffer cells, may be activated by ischemic injury and dysregulation of their response to LPS may contribute to the development of SIRS and acute respiratory distress syndrome. METHODS: Adult male Sprague-Dawley rats were randomly divided into six groups: three groups received total hepatic ischemia for 30 min and three groups had a sham procedure. Twenty-four hours or 3 days after hepatic ischemia/reperfusion injury, rats were treated with LPS (5 mg/kg) or saline and monitored for 4 hr. We collected serum, bronchoalveolar lavage (BAL) fluid, and lung tissue. RESULTS: Serum and BAL cytokine concentrations were significantly increased by i.v. LPS; however, hepatic ischemia/reperfusion injury 24 hr or 3 days before iv LPS ameliorated this cytokine response. The LPS-induced pulmonary neutrophil influx and histopathological changes were similar in sham and hepatic ischemia/reperfusion-injured groups. CONCLUSIONS: Hepatic ischemia/reperfusion injury significantly attenuated the serum and BAL cytokine concentrations, but did not change pulmonary neutrophil influx or histopathological alterations in response to i.v. LPS.


Assuntos
Quimiotaxia de Leucócito/efeitos dos fármacos , Citocinas/sangue , Lipopolissacarídeos/farmacologia , Fígado/irrigação sanguínea , Pulmão/patologia , Neutrófilos/efeitos dos fármacos , Traumatismo por Reperfusão/sangue , Animais , Líquido da Lavagem Broncoalveolar/química , Quimiocina CXCL2 , Injeções Intravenosas , Interleucina-6/análise , Interleucina-6/sangue , Lipopolissacarídeos/administração & dosagem , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Masculino , Monocinas/análise , Monocinas/sangue , Peroxidase/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/análise
6.
N Engl J Med ; 332(11): 719-24, 1995 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-7854380

RESUMO

BACKGROUND: Since the recognition that human immunodeficiency virus is transmissible by blood transfusion there has been increasing public and professional support for autologous blood donations before elective surgery. Autologous blood donation is, however, a more expensive process than the donation of allogeneic blood by community volunteers. Furthermore, there have been recent improvements in the safety of the volunteer blood supply. METHODS: We used a decision-analysis model to assess the cost effectiveness of donating autologous blood for four surgical procedures. Cost data were collected from the observation of transfusion practice at the University of California, Los Angeles, in 1992. Estimates of the risks of transfusion-associated diseases and the costs of treating them came from the medical literature. Cost effectiveness was expressed in dollars per quality-adjusted year of life saved. We performed sensitivity analyses of the variables in our model and examined the effect of strategies suggested to reduce costs. RESULTS: Substituting autologous for allogeneic blood resulted in little expected health benefit (0.0002 to 0.00044 quality-adjusted year of life saved) at considerable additional cost ($68 to $4,783 per unit of blood). The additional cost of autologous blood was primarily a function of the discarding of units that were donated but not transfused and of a more labor-intensive donation process. The cost-effectiveness ratios ranged from $235,000 to over $23 million per quality-adjusted year of life saved. CONCLUSIONS: Given the improved safety of allogeneic transfusions today, the increased protection afforded by donating autologous blood is limited and may not justify the increased cost.


Assuntos
Transfusão de Sangue Autóloga/economia , Cuidados Pré-Operatórios/economia , Transfusão de Sangue/economia , Redução de Custos , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Humanos , Sensibilidade e Especificidade , Transplante Homólogo/economia
7.
Surg Neurol ; 38(3): 236-40, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1440209

RESUMO

We report a case of ruptured intracranial aneurysm from metastatic choriocarcinoma in a patient presenting with intracerebral hemorrhage. Operative evacuation of the hematoma with clipping of a distal right middle cerebral artery aneurysm was performed. Postoperatively, the patient developed hypovolemic shock from spontaneous splenic rupture. Histopathologic examination of the cerebral aneurysm showed choriocarcinoma invading the vessel wall. Metastatic choriocarcinoma should be considered in the differential diagnosis of intracerebral or subarachnoid hemorrhage in women of child-bearing age.


Assuntos
Neoplasias Encefálicas/complicações , Hemorragia Cerebral/cirurgia , Coriocarcinoma/complicações , Aneurisma Intracraniano/etiologia , Ruptura Esplênica/etiologia , Adulto , Aneurisma Roto/etiologia , Aneurisma Roto/cirurgia , Neoplasias Encefálicas/secundário , Hemorragia Cerebral/etiologia , Coriocarcinoma/secundário , Feminino , Humanos , Aneurisma Intracraniano/complicações , Complicações Pós-Operatórias/etiologia , Ruptura Espontânea
8.
Protein Eng ; 4(4): 463-8, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1881872

RESUMO

We have used site-directed insertion and point mutagenesis in an attempt to increase the cytotoxic potency and receptor-binding affinity of the diphtheria-toxin-related interleukin-2 (IL-2) fusion toxins. Previous studies have demonstrated that both the DAB486-IL-2 and DAB389-IL-2 forms of the fusion toxin consist of three functional domains: the N-terminal fragment-A-associated ADP-ribosyltransferase, the hydrophobic-membrane-associating domains, and the C-terminal receptor-binding domain of human IL-2. By insertion mutagenesis we have increased the apparent flexibility of the polypeptide chain between the membrane-associating domains and the receptor-binding domain of this fusion toxin. In comparison to DAB486-IL-2, the cytotoxic potency of the insertion mutants was increased by approximately 17-fold for high-affinity IL-2-receptor-bearing cell lines in vitro. Moreover, competitive displacement experiments using [125I]rIL-2 demonstrate that the increase in cytotoxic potency correlates with an increase in receptor-binding affinity for both the high and intermediate forms of the IL-2 receptor.


Assuntos
Toxina Diftérica/genética , Interleucina-2/genética , Engenharia de Proteínas , Receptores de Interleucina-2/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Ligação Competitiva , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Toxina Diftérica/isolamento & purificação , Toxina Diftérica/metabolismo , Toxina Diftérica/farmacologia , Humanos , Interleucina-2/isolamento & purificação , Interleucina-2/metabolismo , Interleucina-2/farmacologia , Dados de Sequência Molecular , Mutagênese Insercional , Mutagênese Sítio-Dirigida , Ligação Proteica , Conformação Proteica , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Software
9.
J Biol Chem ; 265(20): 11885-9, 1990 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-2195027

RESUMO

We have used cassette and deletion mutagenesis to analyze the structural features of fragment B-related sequences in the fusion toxin DAB486-IL-2 (where IL-2 represents interleukin-2) that are necessary for the efficient delivery of fragment A to the cytosol of target cells. We demonstrate that whereas an intact disulfide bond between Cys461 and Cys471 may be required for the cytotoxic action of native diphtheria toxin, this bond is not required for the cytotoxic action of DAB486-IL-2. The in-frame deletion of the 97 amino acids from Thr387 to His485 of DAB486-IL-2 increases both the potency and the apparent dissociation constant (Kd) of the resulting fusion toxin for high affinity interleukin-2 receptor-bearing target cells. In contrast, the inframe deletion of either the 191 amino acids between Asp291 and Gly483 or the 85 amino acids between Asn204 and Ile290 results in a 1000-fold loss in potency. These regions contain the putative membrane-spanning regions and the amphipathic membrane surface-associating regions of fragment B, respectively. These results indicate that the efficient delivery of the ADP-ribosyltransferase from DAB486-IL-2 to the cytosol requires the membrane-associating domains of fragment B. This function has been postulated to play a role in the diphtherial intoxication of eukaryotic cells. However, unlike native diphtheria toxin, fragment B sequences distal to Thr387 do not enhance the potency of DAB486-IL-2.


Assuntos
Toxina Diftérica/metabolismo , Imunotoxinas/metabolismo , Interleucina-2/metabolismo , Animais , Ligação Competitiva , Transporte Biológico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Clonagem Molecular/métodos , Cistina , Citosol/metabolismo , Toxina Diftérica/genética , Toxina Diftérica/farmacologia , Escherichia coli/genética , Imunotoxinas/farmacologia , Interleucina-2/farmacologia , Cinética , Mutação , Plasmídeos , Receptores de Interleucina-2/efeitos dos fármacos , Receptores de Interleucina-2/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Mapeamento por Restrição , Tirosina
10.
Mol Endocrinol ; 2(3): 263-71, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3398853

RESUMO

We have examined the effects of estrogen and progestin agonist and antagonist ligands on regulation of progesterone receptor (PR) protein and mRNA levels in a variety of human breast cancer cell lines. By Northern blot analysis, using human PR cDNA probes, PR mRNA in T47D and MCF-7 cells appears as five species of approximately 11.4, 5.8, 5.3, 3.5, and 2.8 kilobases. PR mRNA species are not detected in the PR protein-negative breast cancer cell lines MDA-MB-231 and LY2. T47D cells contain high levels of PR mRNA and protein (detected by hormone binding assay or Western blot analysis), and the PR protein and mRNA content of T47D cells are reduced to about 10% of the control level within 48 h of treatment with 10 nM promegestone; 17, 21-dimethyl-19-nor-pregna-4,9-diene-3, 20-dione (R5020) or 16 alpha-ethyl-21-hydroxy-19-nor-pregn-4-ene-3,20-dione (ORG2058), both potent progestins. In contrast, treatment of T47D cells with the antiprogestin 17 beta-hydroxy-11 beta-[4-dimethylaminophenyl]-17 alpha-(1-propynyl)-estra- 4, 9-dien-3-one) (RU38486) reduces PR protein and mRNA levels only transiently. PR protein and mRNA are virtually undetectable in control MCF-7 cells grown in the absence of estrogens. When estradiol is administered to MCF-7 cells, the PR mRNA and protein levels increase gradually and proportionately (10- or 40-fold, respectively, in 3 days).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Neoplasias da Mama/genética , RNA Mensageiro/fisiologia , Receptores de Progesterona/genética , Neoplasias da Mama/fisiopatologia , Estrenos/farmacologia , Antagonistas de Estrogênios/farmacologia , Estrogênios/farmacologia , Feminino , Humanos , Ligantes , Mifepristona , Promegestona/farmacologia , Células Tumorais Cultivadas
11.
Steroids ; 50(1-3): 163-78, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3504058

RESUMO

Research efforts over the past several years have focused on the synthesis of competitive and irreversible aromatase inhibitors and examination of these inhibitors in microsomal preparations, in cell culture, and in vivo. Several 7 alpha-substituted androstenediones have demonstrated high affinity for placental aromatase, with apparent Ki's ranging from 1 to 30 nM. Inactivation of aromatase occurred following incubation with alkylating and enzyme-activated irreversible inhibitors. 7 alpha-(4'-Amino)phenylthio-4-androstene-3,17-dione (7 alpha-APTA) exhibits potent inhibitory activity of aromatase in the MCF-7 human mammary carcinoma cell line with an ED50 of approximately 25 nM. The inhibitor did not bind to the estrogen receptor of the cells in vitro nor induce levels of progesterone receptors in intact cells. In vivo studies of 7 alpha-APTA in the DMBA-induced rat mammary carcinoma model resulted in 80% of the tumors responding completely or partially at doses of 25 and 50 mg/kg body wt/day. Thus, these 7 alpha-substituted steroidal aromatase inhibitors are effective medicinal agents and may be useful for the treatment of estrogen-dependent breast cancer.


Assuntos
Androstadienos/farmacologia , Androstenodiona/farmacologia , Inibidores da Aromatase , Animais , Feminino , Humanos , Ratos , Ratos Endogâmicos , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
12.
J Biol Chem ; 262(18): 8685-9, 1987 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-3597393

RESUMO

Enzyme-activated inhibitors of aromatase would result in effective medicinal agents for modulating estrogen-dependent processes and thus may be useful in controlling reproductive processes and in treating estrogen-dependent diseases such as breast and endometrial cancer. A potential enzyme-activated inhibitor of aromatase, 7 alpha-(4'-amino)phenylthio-1,4-androstadiene-3,17-dione (7 alpha-APTADD), was synthesized and examined in vitro with placental aromatase. Under initial velocity conditions, 7 alpha-APTADD exhibited high affinity for the enzyme and is a potent inhibitor of aromatase with an apparent Ki of 9.9 +/- 1.0 nM and with a Km for androstenedione of 52.5 +/- 5.9 nM. This inhibitor produced a rapid time-dependent, first-order inactivation of aromatase in the presence of NADPH, while no inactivation of aromatase activity was observed in the absence of NADPH. Protection of aromatase from inactivation was observed when the substrate, androstenedione, was included in the incubation mixture containing enzyme, inhibitor, and NADPH. On the other hand, nucleophilic trapping agents such as cysteine did not protect the enzyme from inactivation by 7 alpha-APTADD. Additionally, second enzyme pulse experiments demonstrated identical rates of inactivation, suggesting that the enzyme-activated inhibitor was not being released from the active site of the enzyme. The apparent Kinact for 7 alpha-APTADD is 159 +/- 21 nM and represents the inhibitor concentration required to produce a half-maximal rate of inactivation. The half-time of inactivation at infinite inhibitor concentration was 1.38 +/- 0.92 min and is the most rapid enzyme-activated aromatase inhibitor reported to date. Thus, 7 alpha-APTADD is a potent enzyme-activated inhibitor of aromatase, exhibiting high affinity and rapid inactivation. This inhibitor will be useful in probing the biochemistry of aromatase and should also serve as an effective medicinal agent for the treatment of estrogen-dependent cancers.


Assuntos
Androstadienos/farmacologia , Inibidores da Aromatase , Androstadienos/síntese química , Androstenodiona/farmacologia , Indicadores e Reagentes , Cinética
13.
Arch Oral Biol ; 29(11): 911-20, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6596038

RESUMO

A culture procedure for rat third molars suitable for nutritional-developmental studies is described. Unerupted third molars from 12-day-old rats were cultured in BGJb media containing 20 per cent rat serum and supplemented with 25 mM HEPES buffer, 25 mg ascorbic acid, 20 mg L-glutamine, 12 mg penicillin G and 10 mg streptomycin sulphate per 100 ml of media. Molars were cultured at the liquid-gas interphase using a 50 per cent O2, 45 per cent N2, 5 per cent CO2 gas mixture at 10 lb-psig (pounds per square inch guage). Molar cultures were maintained successfully for 9-14 days without evidence of necrosis, although they developed at a slower rate than in vivo. Molars cultured in 50 per cent O2 compared to those cultured in 21 per cent O2 for periods of 2, 4, 6 and 8 days had higher values for protein, alkaline phosphatase (AP), Ca, P and Ca/P. Vitamin-A-deficiency gave lower values for AP, Ca, P, Ca/P, 45Ca, 35S and [14C]-proline uptake. Histologically, A - molars had atrophic ameloblasts, some foci of squamous metaplasia and abnormal keratin formation. Thus, deficiency of vitamin A imposed during in-vitro development of rat third molars retarded dentinogenesis and interfered with early mineralization of enamel and dentine.


Assuntos
Odontogênese , Deficiência de Vitamina A/fisiopatologia , Envelhecimento , Animais , Meios de Cultura , Dentinogênese , Dente Molar/metabolismo , Dente Molar/patologia , Técnicas de Cultura de Órgãos , Consumo de Oxigênio , Ratos , Ratos Endogâmicos , Calcificação de Dente , Deficiência de Vitamina A/metabolismo , Deficiência de Vitamina A/patologia
15.
J Biol Response Mod ; 2(6): 499-515, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6607323

RESUMO

A single rising dose tolerance trial of rDNA interferon-alpha 2 (IFN-alpha 2) was conducted in eight patients with the diagnoses of non-Hodgkin's lymphoma (NHL), multiple myeloma, and chronic lymphocytic leukemia (CLL). Patients received a total of six i.m. doses at weekly intervals as follows: 1, 3, 10, 30, 60, and 100 x 10(6) IU. Patients were monitored at each dose level for serum IFN activity, anti-IFN antibodies, immunomodulation, clinical toxicity, and response. All patients exhibited clinical toxicity, including fever, chills, fatigue, headache, anorexia, mild-to-moderate leukopenia, nausea, and vomiting. Toxicity was dose-related, with significant side effects occurring in all patients at levels of 10 x 10(6) IU and above and some evidence of tachyphylaxis at higher doses. All side effects, including leukopenia and thrombocytopenia, were of short duration and were resolved within 3-5 days. Fevers, rigors, myalgias, and fatigue were partially alleviated by premedication with acetaminophen or hydrocortisone. Pharmacokinetic data indicated mean peak serum IFN titers greater than 90 at a dose of 10 x 10(6) IU and greater than or equal to 200 at doses greater than or equal to 30 x 10(6) IU 8 h after injection. No anti-IFN antibodies were detected. However, the serum levels achieved at higher doses were not linear, possibly indicating in vivo degradation. Total T cells, B cells, monocytes, and T subsets monitored by flow cytometry with monoclonal antibodies remained essentially constant throughout the trial. Although some patients demonstrated minor augmentations of antibody-dependent cellular cytotoxicity (ADCC) and natural killing (NK) activity at the lowest IFN-alpha 2 doses, the majority of patients demonstrated decreases in NK activity after higher IFN doses. No correlation between immunomodulation and clinical response to IFN was observed. At higher dose levels, the predominant immunomodulatory effect of IFN-alpha 2 was suppression of NK, ADCC, and blastogenic responses to T-cell mitogens and recall antigens. B-cell functional deficits as well as radioresistant T-helper and radiosensitive T-suppressor function assessed in a pokeweed mitogen-driven immunoglobulin secretion assay appeared unaffected by IFN administration. One myeloma patient showed progression and was discontinued after 60 x 10(6) IU. There were four patients (3 NHL, 1 myeloma) who achieved partial remission (greater than or equal to 50% tumor reduction) and three (1 CLL, 2 NHL) who showed objective tumor responses of less than 50%. These data suggest that rDNA IFN-alpha 2 is well-tolerated and may have significant antitumor activity against lymphoproliferative malignancies. Clin


Assuntos
Interferon Tipo I/uso terapêutico , Linfoma/terapia , Mieloma Múltiplo/terapia , Adulto , Idoso , Anticorpos/análise , Linfócitos B/efeitos dos fármacos , Avaliação de Medicamentos , Feminino , Humanos , Imunidade/efeitos dos fármacos , Interferon Tipo I/efeitos adversos , Interferon Tipo I/metabolismo , Cinética , Linfoma/imunologia , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/imunologia , Fenótipo , Linfócitos T/efeitos dos fármacos , Fatores de Tempo
16.
Cancer Res ; 42(8 Suppl): 3334s-3337s, 1982 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7083196

RESUMO

Various C19-steroidal derivatives have been synthesized and evaluated in biochemical assays for their ability to inhibit the biosynthesis of estrogens. Steroids with substitutions on the A or B ring were prepared by Michael addition of various thiol reagents to appropriate dienone intermediates. An in vitro assay using human placental microsomes was used to evaluate aromatase-inhibitory properties. Synthesized compounds that exhibited high inhibitory activity were further evaluated under initial velocity conditions to determine apparent Ki values. Several 7 alpha-substituted androstenediones were effective competitive inhibitors and have apparent Ki values ranging from 18 to 69 nM, with the apparent Km for androstenedione being 63 nM. The most effective competitive inhibitor tested is 7 alpha-(4'-amino)phenylthioandrost-4-ene-3,17-dione with an apparent Ki of 18 nM. Derivatives of this 7 alpha-thioether compound that contain alkylating moieties have been prepared as potential irreversible enzyme inhibitors and demonstrate varying abilities to inactivate the aromatase enzyme. The results of these studies demonstrate that large chemical functionalities such as an aromatic ring with polar substituents can be accommodated in or near the active site of aromatase and, in some cases, can enhance the affinity of the enzyme for the inhibitors.


Assuntos
Androstenodiona/análogos & derivados , Inibidores da Aromatase , Estrogênios/biossíntese , Oxirredutases/antagonistas & inibidores , Placenta/enzimologia , Androstenodiona/farmacologia , Feminino , Humanos , Cinética , Microssomos/enzimologia , Gravidez
17.
Clin Chim Acta ; 92(3): 481-9, 1979 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-436288

RESUMO

A new genetic variant form of glucosephosphate isomerase has been found in a family heterozygous for the mutant allele. The mutant enzyme, unlike other phenotypic variants, does not appear to be the result of a single amino acid replacement. The allozyme exhibits an isoelectric point of 5.7 and is thus much more acidic than the normal enzyme (pI = 9.3). The allozyme has been isolated from placenta and separated from the normal homodimer and heterodimer by isoelectric focusing. The enzyme exhibits normal Km and Ki values for the substrates and competitive inhibitors. The allozyme exhibits a normal pH optimum and thermal stability. However, the molecular specific activity of the variant enzyme as quantitated by radioimmunoassay is significantly lower than normal. Analytical gel filtration revealed that the molecular weight of the weight of the enzyme is significantly lower than the normal enzyme. These data thus suggest that the phenotype is unlike any previously reported and is due to a deletion mutation.


Assuntos
Variação Genética , Glucose-6-Fosfato Isomerase/genética , Alelos , Estabilidade de Medicamentos , Eletroforese em Gel de Amido , Eritrócitos/enzimologia , Feminino , Glucose-6-Fosfato Isomerase/sangue , Heterozigoto , Humanos , Mutação , Placenta/enzimologia , Gravidez , Radioimunoensaio
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