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1.
Med. infant ; 30(3): 258-262, Septiembre 2023. tab, ilus
Artigo em Espanhol | LILACS, UNISALUD, BINACIS | ID: biblio-1515932

RESUMO

La enfermedad renal crónica terminal aumenta el riesgo cardiovascular y puede ocasionar defectos en la mineralización ósea. Para prevenir esto, se debe mantener el fósforo plasmático normal, que depende de la diálisis, los quelantes y la ingesta de fósforo, principalmente de origen inorgánico, incorporado mediante aditivos alimentarios. Las intervenciones nutricionales son pilares en el tratamiento de estos pacientes. El objetivo es facilitar estrategias alimentarias a un grupo de pacientes pediátricos en diálisis, mediante educación alimentaria nutricional, para aumentar el consumo de alimentos naturales, disminuyendo la ingesta de fósforo inorgánico especialmente de los productos cárnicos procesados. Materiales y métodos: se estudió una población pediátrica en diálisis. Se preparó un programa educativo con atención personalizada, instrucción alimentaria y seguimiento mensual, seguido de un taller. Resultados: n: 17 pacientes, edad decimal media de 12,3, 53% sexo masculino, 88% en hemodiálisis. Previo a la intervención el 64,7% consumía productos cárnicos procesados. Luego del taller el 58,8% disminuyó su consumo, el 41,2% aumentó la ingesta de preparaciones caseras, el 53% incorporó nuevos condimentos, de los cuales el 89% presentó al incorporarlos, mejor aceptación a las preparaciones. Conclusiones: la hiperfosfatemia está presente en alrededor del 50% de los pacientes en diálisis asociándose a un incremento entre 20% al 40% del riesgo de mortalidad. La presencia de fósforo oculto en los alimentos y la falta de adherencia hacen prioritario trabajar en programas educativos que favorezcan el aprendizaje colaborativo, centralizados en prácticas culinarias, para brindar herramientas que faciliten una alimentación natural, disminuyendo el consumo de ultraprocesados (AU)


Chronic end-stage renal disease increases the risk of cardiovascular disease and may lead to defects in bone mineralization. In order to prevent these risks, normal plasma phosphorus levels should be maintained. Achieving this goal depends on dialysis, chelators, and phosphorus intake, mainly of inorganic origin, incorporated through food supplements. Nutritional interventions are crucial in the treatment of these patients. The objective is to facilitate nutritional strategies to a group of pediatric dialysis patients, through food education, to increase the consumption of natural foods, decreasing the intake of inorganic phosphorus, especially from processed meat products. Materials and methods: a pediatric population undergoing dialysis was studied. An educational program was prepared with personalized care, nutritional instruction, and monthly follow-up visits, followed by a workshop. Results: n: 17 patients, mean age 12.3 years, 53% male, 88% on hemodialysis. Prior to the intervention, 64.7% consumed processed meat products. After the workshop, 58.8% decreased their consumption, 41.2% increased the intake of homemade food, 53% incorporated new seasonings, of whom 89% reported better acceptance of the preparations when they were incorporated. Conclusions: hyperphosphatemia is observed in around 50% of patients undergoing dialysis and is associated with a 20% to 40% increased risk of mortality. The presence of hidden phosphorus in food and the lack of adherence point to the need for the development of educational programs that promote collaborative learning, focusing on food-preparation practices. These programs should provide tools that facilitate a natural diet, reducing the consumption of ultra-processed food (AU)


Assuntos
Humanos , Pré-Escolar , Criança , Adolescente , Educação Alimentar e Nutricional , Educação de Pacientes como Assunto , Diálise Renal , Insuficiência Renal Crônica/dietoterapia , Hiperfosfatemia/prevenção & controle , Fósforo/efeitos adversos , Estudos Prospectivos , Estudos Longitudinais , Alimento Processado
2.
Leukemia ; 30(3): 649-57, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26464171

RESUMO

Established prognostic tools in patients with myelodysplastic syndromes (MDS) were largely derived from untreated patient cohorts. Although azanucleosides are standard therapies for higher-risk (HR)-MDS, the relative prognostic performance of existing prognostic tools among patients with HR-MDS receiving azanucleoside therapy is unknown. In the MDS Clinical Research Consortium database, we compared the prognostic utility of the International Prognostic Scoring System (IPSS), revised IPSS (IPSS-R), MD Anderson Prognostic Scoring System (MDAPSS), World Health Organization-based Prognostic Scoring System (WPSS) and the French Prognostic Scoring System (FPSS) among 632 patients who presented with HR-MDS and were treated with azanucleosides as the first-line therapy. Median follow-up from diagnosis was 15.7 months. No prognostic tool predicted the probability of achieving an objective response. Nonetheless, all five tools were associated with overall survival (OS, P=0.025 for the IPSS, P=0.011 for WPSS and P<0.001 for the other three tools). The corrected Akaike Information Criteria, which were used to compare OS with the different prognostic scoring systems as covariates (lower is better) were 4138 (MDAPSS), 4156 (FPSS), 4196 (IPSS-R), 4186 (WPSS) and 4196 (IPSS). Patients in the highest-risk groups of the prognostic tools had a median OS from diagnosis of 11-16 months and should be considered for up-front transplantation or experimental approaches.


Assuntos
Antineoplásicos/uso terapêutico , Azacitidina/análogos & derivados , Azacitidina/uso terapêutico , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/tratamento farmacológico , Idoso , Bases de Dados Factuais , Decitabina , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/patologia , Prognóstico , Projetos de Pesquisa , Fatores de Risco , Análise de Sobrevida
3.
J Med Chem ; 52(2): 347-57, 2009 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-19111054

RESUMO

Prostate specific membrane antigen (PSMA) is a validated molecular marker for prostate cancer. A series of glutamate-urea (Glu-urea-X) heterodimeric inhibitors of PSMA were designed and synthesized where X = epsilon-N-(o-I, m-I, p-I, p-Br, o-Cl, m-Cl, p-Cl, p-F, H)-benzyl-Lys and epsilon-(p-I, p-Br, p-Cl, p-F, H)-phenylureido-Lys. The affinities for PSMA were determined by screening in a competitive binding assay. PSMA binding of the benzyllysine series was significantly affected by the nature of the halogen substituent (IC(50) values, Cl < I = Br << F = H) and the ring position of the halogen atom (IC(50) values, p-I < o-I << m-I). The halogen atom had little affect on the binding affinity in the para substituted phenylureido-Lys series. Two lead iodine compounds were radiolabeled with (123)I and (131)I and demonstrated specific PSMA binding on human prostate cancer cells, warranting evaluation as radioligands for the detection, staging, and monitoring of prostate cancer.


Assuntos
Glutamato Carboxipeptidase II/antagonistas & inibidores , Halogênios/química , Neoplasias da Próstata/tratamento farmacológico , Antígenos de Superfície , Cromatografia Líquida de Alta Pressão , Dimerização , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Neoplasias da Próstata/imunologia , Ensaio Radioligante , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta
4.
FEMS Microbiol Lett ; 253(2): 315-21, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16260096

RESUMO

A 205-210 bases long, small RNA (MP200RNA) of Mycoplasma pneumoniae encodes an open reading frame (ORF pmp200) that has the potential to be translated into a 29 amino acids long peptide with nine cysteines. The expression of this peptide in M. pneumoniae was proven indirectly by constructing a gene fusion between the ORF pmp200 and mrfp1, the gene encoding the monomeric red fluorescent protein. The fusion construct was translated in M. pneumoniae. The corresponding fusion protein, with a molecular mass of approximately 35,000 Da, was isolated and the correct sequence was proven by Edman degradation and by mass spectrometry.


Assuntos
Mycoplasma pneumoniae/genética , Proteínas Recombinantes de Fusão/genética , Sequência de Aminoácidos , Western Blotting , Clonagem Molecular , Expressão Gênica , Proteínas Luminescentes , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Bacteriano/biossíntese , RNA Bacteriano/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteína Vermelha Fluorescente
5.
Acta Neurochir (Wien) ; 147(4): 435-42; discussion 442, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15662569

RESUMO

Our purpose is to describe a case of atlanto-occipital dislocation and discuss treatment approaches to minimize subsequent neurological deficits. Traumatic atlanto-occipital dislocation, has traditionally been considered rare and lethal, due to resulting high levels of spinal cord injury. Outcomes are generally expected to be poor. However, recent case reports indicate that survival is increasing. Of patients who survive cranio-cervical dislocation, many endure resulting neurological deficits. We present a rare case of a 23-year-old male, who sustained an atlanto-occipital dislocation in a motor vehicle accident. The patient presented with a Glasgow Coma Scale (GCS) of 11T. Lateral C-spine x-ray and thin-section slices CT delineated a C1 ring fracture on the left side with approximately 1 cm anterior and superior subluxation of the occipital condyles of the cranium in reference to C1. The patient was completely awake, alert, and was following commands. The patient underwent a cranio-cervical stabilization from occiput to C3, using lateral mas screws (C1-C3) and transarticular screws (C2-C3). The Vertex (Medtronics) system used included longitudinal bars connected to the lateral mas plating system, which was subsequently used to place screws within the keel of the occipital bone. Motor strength and sensation remained intact following surgery. One-week post-operation, the patient was ambulating 140 feet, conversationally appropriate, and had a GCS of 15. This case illustrates the possibility for neurosurgical intervention of cranio-cervical dislocations to achieve optimal outcome and demonstrates that survival from this injury is not only conceivable, but recovery of function is also possible.


Assuntos
Articulação Atlantoccipital/lesões , Doenças do Sistema Nervoso Central/prevenção & controle , Luxações Articulares/cirurgia , Fusão Vertebral/métodos , Adulto , Doenças do Sistema Nervoso Central/etiologia , Doenças do Sistema Nervoso Central/fisiopatologia , Vértebras Cervicais/lesões , Fixação Interna de Fraturas/métodos , Humanos , Luxações Articulares/complicações , Masculino , Recuperação de Função Fisiológica/fisiologia , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/cirurgia
7.
Exp Cell Res ; 290(2): 322-31, 2003 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-14567990

RESUMO

The Rab11 family of small GTPases is composed of three members, Rab11a, Rab11b, and Rab25. While recent work on Rab11a and Rab25 has yielded some insights into their function, Rab11b has received little attention. Therefore, we sought to examine the distribution of endogenous Rab11b in epithelial cells. In rabbit gastric parietal cells, unlike Rab11a, Rab11b did not colocalize or coisolate with H(+)/K(+)-ATPase. In MDCK cells, endogenous Rab11b localized to an apical pericentrisomal region distinct from Rab11a. The microtubule agents nocodazole and taxol dramatically alter Rab11a's localization in the cell, while effects on Rab11b's distribution were less apparent. These results indicate that in contrast to Rab11a, the Rab11b compartment in the apical region is not as dependent upon microtubules. While Rab11a is known to regulate transferrin trafficking in nonpolarized cells and IgA trafficking in polarized cells, Rab11b exhibited little colocalization with either of these cargoes. Thus, while Rab11a and Rab11b share high sequence homology, they appear to reside within distinct vesicle compartments.


Assuntos
Células Epiteliais/metabolismo , Células Parietais Gástricas/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Animais , Antineoplásicos/farmacologia , Compartimento Celular , Linhagem Celular , Membrana Celular/metabolismo , Polaridade Celular , Cães , Proteínas de Fluorescência Verde , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Humanos , Imunoglobulina A/metabolismo , Rim/metabolismo , Proteínas Luminescentes/metabolismo , Camundongos , Nocodazol/farmacologia , Paclitaxel/farmacologia , Transporte Proteico , Coelhos , Receptores Fc/metabolismo , Receptores da Transferrina/metabolismo , Transferrina/metabolismo , Proteínas rab de Ligação ao GTP/imunologia
8.
Cancer Res ; 61(4): 1522-6, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11245460

RESUMO

Gene transfer and expression of methotrexate (MTX)-resistant variants of dihydrofolate reductase (DHFR) in normal hematopoietic cells is a potential strategy to permit administration of larger doses of MTX by alleviating drug toxicity in normal cells and tissues that are drug sensitive. We have previously demonstrated that transplantation of marrow from transgenic mice expressing drug-resistant DHFRs conferred upon normal recipient animals resistance to MTX at levels that are usually toxic for hematopoietic and gastrointestinal (GI) tissues. One explanation for the observed protection from GI toxicity by drug-resistant marrow is that MTX could be cleared more rapidly in animals maintaining a more healthy hematopoietic system. To evaluate this possibility, we carried out MTX pharmacokinetic studies in mice that received transplanted transgenic marrow expressing either of two different DHFR variants, administering increasing doses of MTX up to 4 mg/kg/day. Animals received i.p. injection precisely every 24 h. Every 4 days, three animals from each group were sacrificed, and their plasma and intestines were assayed for MTX. Animals transplanted with transgenic Arg-22 DHFR drug-resistant marrow maintained hematocrit levels that were about 4-fold higher at 3 weeks after transplant than those of untreated animals or animals that received normal marrow cells. Animals that received normal marrow did not survive beyond 25 days and did not accumulate higher levels of MTX than animals that received a transgenic marrow transplant. Untreated animals exhibited a higher rate of survival (36 days) but again did not accumulate higher levels of MTX than the transgenic marrow recipients. When the experiment was repeated using transgenic Tyr-22 DHFR marrow, the levels of MTX in the plasma or GI tissues did not differ significantly between groups. Intestinal concentrations of MTX in both experiments were about 4-5-fold higher than those in the plasma. These results indicate that protection from MTX toxicity conferred by expression of drug-resistant DHFR activity in the marrow is not the result of a higher rate of MTX clearance from the circulation in comparison with control animals but a true resistance of hematopoietic and GI tissues to MTX. The maintenance of antifolate levels in animals protected from MTX toxicity implies that this procedure should not compromise the antitumor efficacy of MTX.


Assuntos
Antimetabólitos Antineoplásicos/farmacocinética , Transplante de Medula Óssea , Técnicas de Transferência de Genes , Metotrexato/farmacocinética , Tetra-Hidrofolato Desidrogenase/genética , Animais , Antimetabólitos Antineoplásicos/sangue , Antimetabólitos Antineoplásicos/toxicidade , Medula Óssea/enzimologia , Medula Óssea/fisiologia , Feminino , Terapia Genética/métodos , Mucosa Intestinal/metabolismo , Metotrexato/sangue , Metotrexato/toxicidade , Camundongos , Camundongos Transgênicos , Tetra-Hidrofolato Desidrogenase/metabolismo
9.
Cancer Chemother Pharmacol ; 47(1): 27-33, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11221958

RESUMO

PURPOSE: The gastrointestinal permeability of a number of retinoic acids was determined in order to evaluate whether the gastrointestinal membrane was able to distinguish between retinoids in which the polyene chain was present in several different isomeric forms. In addition, the structure of the six-membered ring was varied in order to determine which portion of the molecule was most important for its recognition by the membrane. The role of bile salt micelle composition in the intestinal absorption of retinoids was also evaluated. METHODS: In situ perfused rat intestinal segment preparations (= 78) were used, and the retinoids were each perfused at a concentration of approximately 1 microg/ml in either simple micelles of sodium taurocholate (10 mM) or mixed micelles of sodium taurocholate/egg phosphatidylcholine (10 mM/10 mM). The flow rate of the perfusate was either 0.1 or 0.35 ml/min. RESULTS: For each retinoid, the mixed micelles were associated with a higher degree of retinoid uptake into the jejunal cells than were the simple micelles. In addition, the permeability was higher when the perfusate flow was greater, indicating that the aqueous boundary layer of the intestine contributes to the resistance to the disappearance of the retinoid from the intestinal lumen. Retinoid structure was also found to have a significant effect on the permeability in the mixed micelle systems at both low and high flow rates, but not with simple micelles. The structure of the six-membered ring was not a major determinant of the permeability. However, the permeability of the retinoids with the polyene chain in the 13-cis position was significantly greater than when the chain was all-trans or in the 9-cis position. CONCLUSIONS: The isomeric position of the polyene chain and the presence of phospholipid in the micellar vehicle have a significant influence on the membrane transport of the retinoic acids.


Assuntos
Absorção Intestinal , Retinoides/farmacocinética , Animais , Isomerismo , Masculino , Ratos , Ratos Sprague-Dawley , Retinoides/química , Relação Estrutura-Atividade
10.
Drug Metab Dispos ; 28(6): 672-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10820140

RESUMO

A CBV [(-)-carbovir, (-)-carbocyclic 2',3'-didehydro-2', 3'-dideoxyguanosine] prodrug, 6AC [(-)-6-aminocarbovir, (-)-carbocyclic 2',3'-didehydro-2', 3'-dideoxy-6-deoxy-6-aminoguanosine], was previously evaluated in rats, and it exhibited superiority to the parent drug in increasing systemic and central nervous system exposure to CBV. The gut wall was determined to be the dominant site of the first-pass activation of 6AC after lumenal administration. If subsequent delivery to the brain is desired, then such a first-pass effect might not be viewed favorably. Because the first-pass conversion of 6AC primarily takes place in the intestine by adenosine deaminase (ADA), quenching of the intestinal activation of 6AC by oral administration of ADA inhibitors may result in an increased 6AC bioavailability, and thus an improved brain exposure to CBV. The objectives of the study were to determine whether the ADA inhibitors 2'-deoxycoformycin and erythro-9-(2-hydroxy-3-nonyl)adenine were capable of achieving a substantial and selective inhibition of gut wall activation of 6AC, and to determine whether the systemic concentrations of 6AC would be thus increased. Thirty-nine male Sprague-Dawley rats were divided into two groups. One group received 6AC by either the portal vein or intralumenally with the coadministration of intralumenal 2'-deoxycoformycin. Similarly, the other group received 6AC with coadministration of erythro-9-(2-hydroxy-3-nonyl)adenine. Substantial suppression of the first-pass conversion of 6AC was achieved with both inhibitors. This inhibition appeared to be relatively selective, allowing the choice of dose of inhibitor that would sufficiently inhibit the first-pass metabolism while leaving the activation capacity in the systemic circulation unaltered. The systemic level of 6AC increased with the escalating dose of inhibitors, thus increasing the driving force for passive uptake into the brain.


Assuntos
Fármacos Anti-HIV/farmacocinética , Didesoxinucleosídeos/farmacocinética , Mucosa Intestinal/metabolismo , Pró-Fármacos/farmacocinética , Adenosina Desaminase/metabolismo , Inibidores de Adenosina Desaminase , Animais , Fármacos Anti-HIV/metabolismo , Didesoxinucleosídeos/metabolismo , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Masculino , Pró-Fármacos/metabolismo , Ratos , Ratos Sprague-Dawley
11.
Carcinogenesis ; 21(2): 179-82, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10657955

RESUMO

This investigation is part of an effort to develop chemoprevention for carcinogenesis of the lung. It focuses on the efficacy of low doses of synthetic glucocorticoids administered either as single agents or in combination with a second compound, myo-inositol. Glucocorticoids are potent inhibitors of carcinogenesis. The use of low doses is important to avoid potential side-effects. The synthetic glucocorticoid budesonide, administered by aerosol for 20 s three times a week, was studied to determine its effects on benzo[a]pyrene-induced pulmonary adenoma formation in female A/J mice. Two dose levels were employed, 10 and 25 microg/kg body wt. The lower dose produced a 34% reduction in lung tumor formation and the higher dose level a 60% reduction in lung tumors. In additional groups of mice, the effects of 0.3% myo-inositol added to the diet was found to reduce pulmonary tumor formation by 53%. The two agents given in combination resulted in a greater inhibition of lung tumor formation than either by itself. Budesonide at 10 microg/kg body wt plus 0.3% myo-inositol reduced the number of tumors by 60% and budesonide at 25 microg/kg body wt plus 0.3% myo-inositol reduced lung tumor formation by 79%. To determine whether a glucocorticoid other than budesonide would have inhibitory effects in this experimental model, beclomethasone dipropionate administered by aerosol for 20 s three times a week was studied as a single agent and showed almost identical inhibitory properties to budesonide. The doses of the glucocorticoids calculated on a daily basis are within the range of those used widely for control of chronic allergic respiratory diseases in the human. The capacity of low doses of inhaled glucocorticoids to prevent pulmonary neoplasia and the enhancement of this preventive effect by myo-inositol, an essentially non-toxic compound, are findings that should encourage further work to evaluate the applicability of these agents to the prevention of neoplasia of the lung in the human.


Assuntos
Adenoma/prevenção & controle , Anticarcinógenos/uso terapêutico , Beclometasona/uso terapêutico , Budesonida/uso terapêutico , Inositol/uso terapêutico , Neoplasias Pulmonares/prevenção & controle , Administração Oral , Aerossóis , Animais , Anticarcinógenos/administração & dosagem , Anticarcinógenos/farmacologia , Beclometasona/administração & dosagem , Beclometasona/farmacologia , Benzo(a)pireno , Budesonida/administração & dosagem , Budesonida/farmacologia , Carcinógenos , Dieta , Sinergismo Farmacológico , Feminino , Inositol/administração & dosagem , Inositol/farmacologia , Neoplasias Pulmonares/induzido quimicamente , Camundongos , Camundongos Endogâmicos A , Tamanho da Partícula
12.
Cancer Res ; 59(3): 590-6, 1999 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9973205

RESUMO

We quantified urinary levels of two metabolites of the tobacco-specific lung carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in people who had stopped smoking: 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and its O-glucuronide, 4-[(methylnitrosamino)-1-(3-pyridyl)but-1-yl]-beta-O-D-glucosiduronic acid (NNAL-Gluc). Twenty-seven people completed the study. Thirteen used the nicotine patch starting at the quit date, whereas the others used no patch. Two 24-h urine samples were collected on 2 consecutive days before smoking cessation; blood was also obtained. Beginning at their quit date, subjects provided 24-h urine samples on days 7, 21, 42, 70, 98, and 126, and some subjects also provided samples at later times. The urine was analyzed for NNAL, NNAL-Gluc, nicotine plus nicotine-N-glucuronide, and cotinine plus cotinine-N-glucuronide. Some blood samples were also analyzed for NNAL. The decline of urinary NNAL and NNAL-Gluc after smoking cessation was much slower than expected. This was clearly demonstrated by comparison with cotinine and nicotine levels in urine. One week after smoking cessation, 34.5% of baseline NNAL plus NNAL-Gluc was detected in urine, whereas the corresponding values for cotinine and nicotine were 1.1 and 0.5%, respectively. Even 6 weeks after cessation, 7.6% of the original levels of NNAL plus NNAL-Gluc remained. In some subjects, NNAL plus NNAL-Gluc were detected 281 days after cessation. The distribution half-life for NNAL and NNAL-Gluc was 3-4 days, whereas the elimination half-life was 40-45 days. Total body clearance of NNAL was estimated to be 61.4 +/- 35.4 ml/min, and volume of distribution in the beta-phase was estimated to be 3800 +/- 2100 liters, indicating substantial distribution into the tissues. Parallel studies in rats treated chronically or acutely with NNK in the drinking water support the conclusion that NNAL has a large volume of distribution. There was no effect of the nicotine patch on levels of NNAL plus NNAL-Gluc, indicating that NNK is not formed endogenously from nicotine. The results of this study demonstrate that NNAL and NNAL-Gluc are slowly cleared from the body after smoking cessation, indicating the presence of a high-affinity compartment where NNK, NNAL, and/or NNAL-Gluc are retained or sequestered and slowly released.


Assuntos
Carcinógenos/farmacocinética , Glucuronatos/urina , Nitrosaminas/urina , Abandono do Hábito de Fumar , Adulto , Animais , Cotinina/urina , Feminino , Glucuronatos/farmacocinética , Humanos , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/urina , Masculino , Pessoa de Meia-Idade , Nicotina/urina , Nitrosaminas/metabolismo , Nitrosaminas/farmacocinética , Ratos , Ratos Endogâmicos F344
13.
J Med Chem ; 41(20): 3901-8, 1998 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-9748365

RESUMO

The availability of synthetic hypusine and deoxyhypusine has made it possible to develop analytical methods which allow for the measurement of these compounds in various tissues. The methods involve dansylation of extracts from the pellet remaining after perchloric acid precipitation of cell or tissue homogenates, followed by high-performance liquid chromatography. To demonstrate the utility of this approach, the impact of four polyamine analogues, N1,N11-diethylnorspermine (DENSPM), N1,N14-diethylhomospermine (DEHSPM), 1,6,12-triazadodecane [(4,5) triamine], and 1,7, 13-triazatridecane [(5,5) triamine], on hypusine levels in a human T-cell line (JURKAT) is evaluated. All four analogues are active in controlling cell growth and compete well with spermidine for the polyamine transport apparatus. After 144 h of exposure to JURKAT cells, DENSPM reduces putrescine to below detectable limits and spermidine to 10% of the level in control cells. The other three analogues diminish both putrescine and spermidine to below detectable limits. The effectiveness with which the compounds lower spermine levels is DENSPM > DEHSPM > (4,5) triamine > (5,5) triamine. The analogues decrease the activities of ornithine decarboxylase and S-adenosylmethionine decarboxylase in a similar fashion. Of the four polyamines, DENSPM and DEHSPM are potent at lowering intracellular hypusine levels after 144 h: 59 +/- 9% and 73 +/- 12% of control levels, respectively. The other two analogues have marginal effects.


Assuntos
Antineoplásicos/farmacologia , Lisina/análogos & derivados , Espermina/análogos & derivados , Adenosilmetionina Descarboxilase/antagonistas & inibidores , Animais , Antineoplásicos/análise , Antineoplásicos/metabolismo , Transporte Biológico , Divisão Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Compostos de Dansil/química , Inibidores Enzimáticos/análise , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Células Jurkat , Leucemia L1210/metabolismo , Leucemia L1210/patologia , Lisina/análise , Lisina/biossíntese , Lisina/química , Inibidores da Ornitina Descarboxilase , Espermidina/metabolismo , Espermina/análise , Espermina/metabolismo , Espermina/farmacologia , Células Tumorais Cultivadas
14.
Eur J Immunol ; 28(2): 560-9, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9521066

RESUMO

We examined the CD8+ T cell response to lymphocytic choriomeningitis virus (LCMV) in mice doubly transgenic for an LCMV-specific TCR and for either bcl-xL or bcl-2. Clonal down-sizing of the anti-viral CD8+ T cell response and the generation of T cell memory was not influenced by constitutive expression of these anti-apoptotic proteins in T cells. Expression of Bcl-xL or Bcl-2 did, however, prevent LCMV peptide-induced peripheral deletion of mature CD8+ T cells in vivo and apoptosis of activated LCMV-specific effector T cells in vitro. The CD8+ T cells "rescued" by Bcl-xL or Bcl-2 from peptide antigen-induced cell death were anergic and this could not be reversed by addition of IL-2 in vitro or by adoptive transfer into antigen-free recipient mice followed by LCMV infection in vivo. Taken together, we show here that 1) Bcl-xL or Bcl-2 are functionally equivalent in their ability to modulate CD8+ T cell survival in vivo, 2) distinct apoptosis signaling pathways exist in CD8+ T cells, one that can be inhibited by Bcl-2 or Bcl-xL and one that cannot be blocked, and 3) apoptosis of CD8+ effector T cells during the declining phase of an immune response is not prevented by constitutive expression of the anti-apoptotic proteins Bcl-xL and Bcl-2.


Assuntos
Antígenos Virais , Deleção Clonal/imunologia , Glicoproteínas/imunologia , Homeostase/imunologia , Coriomeningite Linfocítica/imunologia , Fragmentos de Peptídeos/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Subpopulações de Linfócitos T/metabolismo , Proteínas Virais , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Apoptose/imunologia , Linfócitos T CD8-Positivos/imunologia , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Anergia Clonal/genética , Deleção Clonal/efeitos dos fármacos , Deleção Clonal/genética , Regulação da Expressão Gênica/imunologia , Glicoproteínas/administração & dosagem , Homeostase/efeitos dos fármacos , Homeostase/genética , Injeções Intraperitoneais , Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fragmentos de Peptídeos/administração & dosagem , Proteínas Proto-Oncogênicas c-bcl-2/administração & dosagem , Proteínas Proto-Oncogênicas c-bcl-2/genética , Subpopulações de Linfócitos T/imunologia , Transgenes/imunologia , Proteína bcl-X
15.
Cancer Res ; 58(7): 1325-31, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9537223

RESUMO

E2F/DP heterodimers play a pivotal role in the regulation of cell growth and differentiation. A decrease in E2F/DP activity occurs during cell cycle arrest and differentiation. However, very little is known about the specific role of the various E2F/DP members along the transition from proliferation to terminal differentiation. We have previously shown that E2F4 accounts for the vast majority of the endogenous E2F in differentiating muscle cells. Here, we show that E2F4, which lacks a nuclear localization signal (nls), is distributed in both the nucleus and the cytoplasm, in either asynchronously growing myoblasts or differentiated myotubes. E2F4 nuclear accumulation is induced by the binding in the cytoplasm with specific partners p107, pRb2/p130, and DP3delta, an nls-containing spliced form of DP3, which provide the nls. Although overexpression of E2F4/DP3delta reactivates the cell cycle in quiescent cells, the E2F4 nuclear accumulation induced by pRb2/p130 and p107 correlates with cell growth arrest Moreover, E2F4/DP3delta-induced cell cycle reactivation is efficiently counteracted by either p107 or pRb2/p130 overexpression. Reinduction in quiescent cells of DNA synthesis by E2F1/DP1 overexpression is abrogated by coexpression of pRb and is hampered by MyoD overexpression. Both pRb2/p130 and pRb, as well as MyoD, are up-regulated in myotubes. Accordingly, multinucleated myotubes, which are induced to reenter the S-phase by oncoviral proteins, are refractory to cell cycle reactivation by forced expression of E2F4/DP3delta or E2F1/DP1. Thus, E2F/DP repression represents only one of multiple redundant circuits that control the postmitotic state in terminally differentiated cells and that are targeted by adenovirus E1A and SV40 large T antigen.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Proteínas de Drosophila , Substâncias de Crescimento/fisiologia , Músculos/citologia , Músculos/metabolismo , Fatores de Transcrição/fisiologia , Translocação Genética/fisiologia , Animais , Ciclo Celular/fisiologia , Núcleo Celular/metabolismo , Células Cultivadas , Citoplasma/metabolismo , DNA/biossíntese , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/metabolismo , Dimerização , Fator de Transcrição E2F4 , Vetores Genéticos , Substâncias de Crescimento/biossíntese , Substâncias de Crescimento/metabolismo , Camundongos , Microinjeções , Músculos/fisiologia , Frações Subcelulares/metabolismo , Transativadores/biossíntese , Transativadores/metabolismo , Fatores de Transcrição/biossíntese , Fatores de Transcrição/metabolismo , Regulação para Cima
16.
Cancer Res ; 57(24): 5489-92, 1997 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9407956

RESUMO

This investigation is part of a continuing effort to develop effective chemoprevention for carcinogenesis of the lung. The present study explores the use of aerosol administrations for this purpose. The agent selected for initial study was the synthetic glucocorticoid budesonide. This selection was based on previous work in which budesonide added to the diet was found to inhibit pulmonary adenoma formation in female A/J mice. However, high dose levels were required, i.e., of the order of 300 microg/kg, of body weight [L. W. Wattenberg and R. D. Estensen, Carcinogenesis (Lond.), 18: 2015-2017, 1997]. For aerosol administration of budesonide, a nose-only technique has been developed that entails nebulization of the compound dissolved in ethanol and subsequent stripping off of the solvent (less than 3 microl ethanol/liter of air remaining at the site of inhalation). The budesonide particles produced by the apparatus had a mass median aerodynamic diameter of less than 1 microm. An experiment has been carried out in which the inhibitory effects of aerosolized budesonide, given for 1 min six times a week, were studied. Concentrations of budesonide of 26, 81, and 148 microg/liter of air (calculated doses of 23, 72, and 126 microg/kg of body weight) were used. The aerosols were started 1 week after three oral administrations of benzo(a)pyrene (2 mg/20 g of body weight) to female A/J mice. All three doses of budesonide resulted in more than 80% inhibition of pulmonary tumor formation compared to the aerosol control and 90% or greater compared to mice not exposed to aerosol. The difference in inhibition is due to the aerosol procedure itself, which produces a reduction in tumor formation. A decrease in splenic weight (evidence of a systemic effect) occurred at all doses of budesonide. To the best of our knowledge, this is the first published effort at the use of aerosol administration to prevent neoplasia of the respiratory tract. The results of the present study show that administration of a potential chemopreventive agent by aerosol at a low dose can inhibit the occurrence of pulmonary carcinogenesis in female A/J mice.


Assuntos
Anticarcinógenos/uso terapêutico , Budesonida/uso terapêutico , Neoplasias Pulmonares/prevenção & controle , Administração por Inalação , Aerossóis , Animais , Anticarcinógenos/administração & dosagem , Anticarcinógenos/farmacocinética , Benzo(a)pireno , Peso Corporal/efeitos dos fármacos , Budesonida/administração & dosagem , Budesonida/farmacocinética , Carcinógenos , Feminino , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos A , Tamanho da Partícula
17.
J Exp Med ; 183(4): 1367-75, 1996 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8666895

RESUMO

The cellular basis of T cell memory is a controversial issue and progress has been hampered by the inability to induce and to trace long-term memory T cells specific for a defined antigen in vivo. By using the murine model of lymphocytic choriomeningitis virus (LCMV) infection and an adoptive transfer system with CD8+ T cells from transgenic mice expressing an LCMV-specific T cell receptor, a population of authentic memory T cells specific for LCMV was generated and analyzed in vivo. The transgenic T cells that have expanded (1,000-fold) and then decreased (10-fold) in LCMV-infected C57BL/6 recipient mice exhibited the following characteristics: they were (a) of larger average cell size than their naive counterparts but smaller than day 8 effector cells; (b) heterogeneous with respect to expression of cell surface "memory" markers; and (c) directly cytolytic when isolated from recipient spleens. The time-dependent proliferative activity of these LCMV-specific memory T cells was analyzed in the recipients by bromodeoxyuridine labeling experiments in vivo. The experiments revealed that LCMV-specific CD8+ memory T cells can persist in LCMV-immune mice for extended periods of time (>2 mo) in the absence of cell division; the memory population as a whole survived beyond 11 mo.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Memória Imunológica , Coriomeningite Linfocítica/imunologia , Sequência de Aminoácidos , Animais , Biomarcadores , Citotoxicidade Imunológica , Citometria de Fluxo , Imunoterapia Adotiva , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Dados de Sequência Molecular , Fragmentos de Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T/genética , Baço/citologia , Baço/imunologia , Proteínas Virais/imunologia
18.
Cancer ; 77(8): 1544-50, 1996 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-8608541

RESUMO

BACKGROUND: Primary leptomeningeal melanomas are rare tumors that originate in the leptomeninges and are associated with a poor prognosis and no response to radiation and chemotherapy. These tumors rarely metastasize outside the central nervous system. Recombinant interleukin-2-(rIL-2) is a cytokine that activates natural killer cells and lymphokine-activated killer cells, augments their antitumor effects, and recruits and activates cytotoxic T lymphocytes. We have hypothesized that rIL-2 may prolong disease free survival in a patient with primary leptomeningeal melanoma. METHODS: The patient was treated with intrathecal rIL-2 via lumbar puncture daily for 5 days, the weekly for 5 weeks. To investigate whether rIL-2 induced a favorable clinical response, the following parameters were monitored: survival, neurologic status, cerebrospinal fluid (CSF) analysis, visual fields, and magnetic resonance imaging (MRI) of the lumbosacral spine. RESULTS: The patient is still alive and disease free 15 months after receiving rIL-2, and his neurologic status remains unchanged. The CFS glucose concentration, undetectable prior to therapy, has become normal. Repeated cytologic examinations of CSF were negative for malignant cells. The visual field examinations have remained unchanged. MRI scans of the lumbosacral spine have shown the development of arachnoiditis, but no recurrence of the mass lesion. CONCLUSIONS: The tumor response in this patient, as measured by remarkable disease free survival and normalization of the CSF glucose concentration, illustrates the potential benefits of intrathecal rIL-2 in the treatment of patients with this otherwise rapidly fatal disease.


Assuntos
Antineoplásicos/uso terapêutico , Interleucina-2/uso terapêutico , Melanoma/tratamento farmacológico , Neoplasias Meníngeas/tratamento farmacológico , Animais , Cricetinae , Intervalo Livre de Doença , Glucose/líquido cefalorraquidiano , Humanos , Injeções Espinhais , Masculino , Melanoma/líquido cefalorraquidiano , Neoplasias Meníngeas/líquido cefalorraquidiano , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico
19.
Ophthalmology ; 102(4): 594-8, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7724176

RESUMO

BACKGROUND: Global orbital infarction results from ischemia of the intraocular and intraorbital structures due to hypoperfusion of the ophthalmic artery and its branches. PATIENTS: The authors describe six patients in whom acute proptosis, ophthalmoplegia, and blindness developed immediately after surgery for intracranial aneurysms. RESULTS: All patients underwent standard frontotemporal craniotomies to clip their aneurysms. In all patients, proptosis, ophthalmoplegia, and blindness developed in the immediate postoperative period; fundus abnormalities included retinal edema, retinal arteriolar narrowing and other vascular abnormalities, and pale optic disc swelling. Some patients had facial and corneal anesthesia. Ophthalmoplegia and facial anesthesia improved in most patients, but none regained any vision in the affected eye. CONCLUSION: Orbital infarction syndrome is a rare complication of neurosurgical procedures. Increased orbital pressure probably reduced ophthalmic artery and collateral arterial perfusion, resulting in ischemia of the intraocular and intraorbital structures. There may be multiple factors that compound the risk for orbital infarction, and patients with subarachnoid hemorrhage, increased intracranial pressure, anomalous arterial or venous circulation, or impaired orbital venous outflow seem particularly vulnerable.


Assuntos
Infarto/etiologia , Aneurisma Intracraniano/cirurgia , Órbita/irrigação sanguínea , Complicações Pós-Operatórias , Adulto , Idoso , Cegueira/etiologia , Exoftalmia/etiologia , Feminino , Fundo de Olho , Humanos , Infarto/complicações , Aneurisma Intracraniano/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Oftalmoplegia/diagnóstico por imagem , Oftalmoplegia/etiologia , Radiografia , Síndrome
20.
Thromb Haemost ; 71(2): 173-9, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8191394

RESUMO

Since 1985, viral-attenuated blood products have been available for the treatment of patients with hemophilia. Unfortunately, similar viral-attenuated blood products, enriched for von Willebrand factor (vWF), have not been readily available for the treatment of patients with von Willebrand disease (vWD). In the current study, we examined the clinical efficacy and in vivo properties of two viral-attenuated factor VIII products, Koate-HS and Koate-HP, in the treatment of patients with vWD. Twenty-one (21) infusions were evaluated in 17 different vWD patients (4 with type IA; 8 with Type IIA; 1 with Type IID; 4 with type III). Seven (7) patients received Koate-HS and 12 patients received Koate-HP (2 patients received both products; 1 patient was studied three times). Von Willebrand factor antigen, ristocetin cofactor, bleeding time, and the multimeric composition of vWF were determined pre- and post-infusion. Complete or partial correction of prolonged bleeding times was observed in 2 of the 6 patients tested following treatment with Koate-HS and in 7 out of 11 patients tested following treatment with Koate-HP. Surgery was performed on five of these patients, two of whom were treated with Koate-HS and three of whom were treated with Koate-HP. In the surgical patients, clinical hemostasis was achieved regardless of whether the bleeding time was corrected. We conclude that both Koate-HS and Koate-HP can be utilized successfully in the treatment of patients with vWD in spite of the lack of high molecular weight multimers of vWF in these products.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Fator VIII/uso terapêutico , Doenças de von Willebrand/tratamento farmacológico , Adolescente , Adulto , Tempo de Sangramento , Contaminação de Medicamentos , Fator VIII/química , Fator VIII/isolamento & purificação , Hemostasia/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Conformação Proteica , Segurança , Vírus/isolamento & purificação , Doenças de von Willebrand/sangue , Doenças de von Willebrand/cirurgia , Fator de von Willebrand/metabolismo
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