RESUMO
We performed an in-vitro study testing the chemosensitivity of peritoneal cancer cell lines (SW620, HCT116, MKN45, 23,132/87, OAW42) to various cytostatic drug regimens. A duplex drug, characterized by reversible linking of the antimetabolites 2'-deoxy-5-fluorouridine (5-FdU) and 3'-C-ethynylcytidine (ECyd), was compared to oxaliplatin or to cisplatin plus doxorubicin. The experiments were designed to reflect the conditions of intraperitoneal chemotherapy. CASY® (Cell Analysis System) technology was used to compare the impact of incubation temperature/duration and drug concentration on the viability of the cancer cell lines versus normal human dermal fibroblasts. Two incubation scenarios were explored: (i) hyperthermic intraperitoneal chemotherapy (HIPEC) with 1 h of incubation at 42 °C, and (ii) pressurized intraperitoneal aerosol chemotherapy (PIPAC) with several successive incubations at 37 °C. Under HIPEC conditions, oxaliplatin induced a potent temperature-dependent growth inhibition of colon cancer cells not seen with the duplex drug. Under PIPAC conditions, the duplex drug achieved the same growth inhibition at a fraction of the dose level required with oxaliplatin. Gastric and ovarian cancer cells were more sensitive to cisplatin plus doxorubicin than to the duplex drug under PIPAC conditions. The duplex drug suggests itself, notably in cases of platinum resistance, as an alternative or addition to intraperitoneal chemotherapies when platinum-based PIPAC technology is used. Using it with HIPEC technology is not recommended. Higher doses of the duplex drug will enhance growth inhibition, albeit at the cost of a severely reduced difference in chemosensitivity between tumor and normal cells. Our findings provide orientation for PIPAC-based personalized intraperitoneal chemotherapy.
Assuntos
Proliferação de Células/efeitos dos fármacos , Citidina/análogos & derivados , Citostáticos/farmacologia , Desoxiuridina/análogos & derivados , Hipertermia Induzida , Neoplasias Peritoneais/tratamento farmacológico , Adulto , Idoso , Apoptose/efeitos dos fármacos , Cisplatino/farmacologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Citidina/farmacologia , Desoxiuridina/farmacologia , Doxorrubicina/farmacologia , Feminino , Humanos , Técnicas In Vitro , Pessoa de Meia-Idade , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Oxaliplatina/farmacologia , Neoplasias Peritoneais/patologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Células Tumorais CultivadasRESUMO
In mammals, thalamic axons are guided internally toward their neocortical target by corridor (Co) neurons that act as axonal guideposts. The existence of Co-like neurons in non-mammalian species, in which thalamic axons do not grow internally, raised the possibility that Co cells might have an ancestral role. Here, we investigated the contribution of corridor (Co) cells to mature brain circuits using a combination of genetic fate-mapping and assays in mice. We unexpectedly found that Co neurons contribute to striatal-like projection neurons in the central extended amygdala. In particular, Co-like neurons participate in specific nuclei of the bed nucleus of the stria terminalis, which plays essential roles in anxiety circuits. Our study shows that Co neurons possess an evolutionary conserved role in anxiety circuits independently from an acquired guidepost function. It furthermore highlights that neurons can have multiple sequential functions during brain wiring and supports a general role of tangential migration in the building of subpallial circuits.
Assuntos
Vias Aferentes/fisiologia , Orientação de Axônios/genética , Movimento Celular/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Tegmento Pontino , Tálamo , Animais , Animais Recém-Nascidos , Toxina da Cólera/metabolismo , Desoxiuridina/análogos & derivados , Desoxiuridina/metabolismo , Embrião de Mamíferos , Feminino , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas com Homeodomínio LIM/genética , Proteínas com Homeodomínio LIM/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Tegmento Pontino/citologia , Tegmento Pontino/embriologia , Tegmento Pontino/crescimento & desenvolvimento , Gravidez , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/metabolismo , Tálamo/citologia , Tálamo/embriologia , Tálamo/crescimento & desenvolvimento , Fator Nuclear 1 de Tireoide/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Tissue regeneration using adult stem cells (ASCs) has significant potential as a novel treatment for many degenerative diseases. Previous studies have established that age negatively affects the proliferation status and differentiation potential of ASCs, suggesting a possible limitation in their potential therapeutic use. Therefore, we hypothesized that apple extract might exert beneficial effects on ASCs. The specific objectives were to investigate the proliferative effect of apple ethanol extract on human adipose tissue-derived mesenchymal stem cells (ADSCs) and human cord blood-derived mesenchymal stem cells (CB-MSCs), and identify the possible molecular mechanisms. Apple extract promoted proliferation of ADSCs and CB-MSCs as determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Click-iT 5-ethynyl-2'-deoxyuridine flow cytometry assays. In addition, phosphorylation of p44/42 MAPK (ERK), mammalian target of rapamycin (mTOR), p70 S6 kinase (p70S6K), S6 ribosomal protein (S6RP), eukaryotic initiation factor (eIF) 4B and eIF4E was induced stepwise in ADSCs. Furthermore, apple extract significantly induced the production of vascular endothelial growth factor and interleukin-6 in both ADSCs and CB-MSCs. Similarly, apple extract-induced phosphorylation of the mTOR/p70S6K/S6RP/eIF4B/eIF4E pathway was blocked by pretreatment with PD98059, a specific ERK inhibitor. These results indicate that apple extract-induced proliferation of ADSCs under serum-free conditions is mediated by ERK-dependent cytokine production. Moreover, the beneficial effect of apple extract on proliferation of ASCs may overcome the limitation in therapeutic use of stem cells in tissue regeneration and maintenance of stem cell homeostasis.
Assuntos
Células-Tronco Adultas/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Malus , Células-Tronco Mesenquimais/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tecido Adiposo , Adulto , Células-Tronco Adultas/fisiologia , Diferenciação Celular , Desoxiuridina/análogos & derivados , Desoxiuridina/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Sangue Fetal , Humanos , Interleucina-6/metabolismo , Células-Tronco Mesenquimais/fisiologia , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Regeneração , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Sais de Tetrazólio , Tiazóis , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Oligodeoxynucleotides containing 5-carboxyvinyl-2'-deoxyuridine ((CV) U-containing ODNs) for successful site-specific transition of cytosine to uridine by photo-cross-linking have three parts: the complementary sequence, hairpin loop and the 5'-terminal photoresponsive nucleobase (CV) U. Photo-cross-linking with (CV) U-containing ODNs was performed using UV (366 nm) irradiation, followed by heat treatment for deamination. The cross-linked nucleotide was cleaved by photosplitting (UV, 312 nm). The products were analyzed using restriction fragment length polymorphism and fluorescence measurements. In previous studies, we have successfully performed site-directed photochemical base substitution toward a synthetic single-stranded 100-mer ODN target (ss100-nt) and in vitro-synthesized full-length blue fluorescent protein mRNA as targets. Although the efficiency of C-to-U site-specific transition strongly depends on the sequence and structure of (CV) U-containing ODNs, the relationship between (CV) U-containing ODNs and the deamination efficiency of targeted editing remains unclear. Therefore, in this study, we attempted to identify the optimal sequence and primary structure of (CV) U-containing ODNs for site-directed specific transition. To evaluate the structure-deamination efficiency relationship, a series of eight (CV) U-containing ODNs were designed and studied. We showed that the optimal deamination efficiency was achieved with ODNs having a complementary sequence length slightly more than 14 nt and a hairpin length of 9 nt.
Assuntos
Desoxiuridina/análogos & derivados , Conformação de Ácido Nucleico , Edição de RNA , Sequência de Bases , Western Blotting , Desaminação , Espectrometria de Fluorescência , Raios UltravioletaRESUMO
Heterologous expression of the Drosophila melanogaster multi-substrate deoxyribonucleoside kinase (Dm-dNK) increases the sensitivity of cancer cells to several cytotoxic nucleoside analogs. Thus, it may be used as a suicide gene in combined gene/chemotherapy treatment of cancer. To further characterize this potential suicide gene, we constructed two retroviral vectors that enabled the expression of Dm-dNK in cancer cells. One vector harbored the wildtype enzyme that localized to the nucleus. The other vector harbored a mitochondrial localized mutant enzyme that was constructed by deleting the nuclear localization signal and fusing it to a mitochondrial import signal of cytochrome c oxidase. A thymidine kinase-deficient osteosarcoma cell line was transduced with the recombinant viruses. The sensitivity and bystander cell killing in the presence of pyrimidine nucleoside analogs (E)-5-(2-bromovinyl)2'deoxyuridine and 1-ß-D-arabinofuranosylthymine were investigated. Tanshinone IIA is a constituent of Danshen; a traditional Chinese medicine used in the treatment of cardiovascular diseases. This study also looked at the influence of Tanshinone IIA on the bystander effect and the underlying mechanisms. We showed that sensitivity of the osteosarcoma cell line to the nucleoside analogs and the efficiency of bystander cell killing were independent of the subcellular localization of Dm-dNK. The enhanced effect of tanshinone IIA on the bystander effect was related to the increased expression of Cx43 and Cx26.
Assuntos
Abietanos/administração & dosagem , Terapia Genética , Osteossarcoma/tratamento farmacológico , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Animais , Efeito Espectador , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/genética , Conexina 26 , Conexinas , Desoxiuridina/administração & dosagem , Desoxiuridina/análogos & derivados , Drosophila melanogaster/enzimologia , Drosophila melanogaster/genética , Galactose/administração & dosagem , Galactose/análogos & derivados , Vetores Genéticos , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Sinais de Localização Nuclear/genética , Osteossarcoma/genética , Osteossarcoma/patologia , Fosfotransferases (Aceptor do Grupo Álcool)/biossíntese , Retroviridae/genética , Timina/administração & dosagem , Timina/análogos & derivadosRESUMO
OBJECTIVE: To investigate the effects and underlying molecular mechanisms of icariin (ICA) on self-renewal and differentiation of neural stem cells (NSCs). METHODS: NSCs were derived from forebrains of mice embryos by mechanical dissociation into single cell suspension. The self-renewal of NSCs was measured by neurosphere formation assay. The proliferation of NSCs was detected by water-soluble tetrazolium (WST) and 5-ethynyl-2'-deoxyuridine (EdU) incorporation assay. Protein expression of neuron-specific marker tubulin-ßIII(TuJ1) and astrocyte-specific marker glial fibrillary acidic protein (GFAP) were measured by immunofluorescence and Western blotting. Using microarray, the differentially expressed genes (DEGs) were screened between NSCs with or without ICA treatment. The signaling pathways enriched by these DEGs and their role in mediating effects of ICA were analyzed. RESULTS: ICA significantly promoted neurosphere formation of NSCs cultured in growth protocol in a dose-dependent manner and achieved the maximum effects at 100 nmol/L. ICA also increased optical absorbance value and EdU incorporation into nuclei of NSCs. ICA had no significant effects on the percentage of TuJ1 or GFAP-positive cells, and TuJ1 or GFAP protein expression in NSCs cultured in differentiation protocol. A total of 478 genes were found to be differentially regulated. Among signaling pathways significantly enriched by DEGs, mitogen activated protein kinase (MAPK) pathway was of interest. Blockade of extracellular signal-regulated kinase (ERK)/MAPK, other than p38/MAPK subfamily pathway partially abolished effects of ICA on neurosphere formation and EdU incorporation of NSCs. CONCLUSION: ICA can promote the selfrenewal of NSCs at least partially through ERK/MAPK signaling pathway.
Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Flavonoides/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Animais , Agregação Celular/efeitos dos fármacos , Agregação Celular/genética , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Desoxiuridina/análogos & derivados , Desoxiuridina/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Células-Tronco Neurais/enzimologiaRESUMO
The radioiodinated 3'-fluorothymidine (FLT) analogue 3'-fluoro-5-[(131)I]iodo-2'-deoxyuridine ([(131)I]FLIdU) was synthesized, with iodine mimicking the methyl group of pyrimidine. [(131)I]FLIdU was accessible by direct electrophilic iodination using Iodogen as oxidant. Optimized amounts of the oxidant allowed radiochemical yields of about 70% after a reaction time of 10 min in an aqueous buffer medium at 90 degrees C. The uptake of [(131)I]FLIdU in a DoHH2 leukemia xenograft mouse model and in healthy mice revealed moderate FLIdU accumulation, followed by a significant washout of activity in proliferating tissues such as splenic and tumor tissues. In contrast, intraperitoneal coinjection with [(18)F]FLT showed high uptake and high activity retention up to 2 h, in both splenic and tumor tissues. Uptake in stomach tissues and increasing fractions of [(131)I]iodide in urine indicated metabolic instability of [(131)I]FLIdU due to rapid deiodination. Therefore, [(131)I]FLIdU alone does not seem to be a promising compound, neither for diagnostic imaging nor for potential therapeutic applications.
Assuntos
Desoxiuridina/análogos & derivados , Didesoxinucleosídeos/farmacocinética , Linfoma/metabolismo , Animais , Linhagem Celular Tumoral , Desoxiuridina/química , Desoxiuridina/farmacocinética , Didesoxinucleosídeos/química , Avaliação Pré-Clínica de Medicamentos , Humanos , Marcação por Isótopo/métodos , Linfoma/diagnóstico por imagem , Taxa de Depuração Metabólica , Camundongos , Camundongos SCID , Especificidade de Órgãos , Cintilografia , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição TecidualRESUMO
[chemical reaction: see text]. We report here the synthesis of the 5'-[benzhydryloxybis(trimethylsilyloxy)]silyl-2'-methylseleno-2'-deoxyuridine phosphoramidite and its incorporation into oligonucleotides by solid-phase synthesis. The coupling yield of this phosphoramidite into oligonucleotides is higher than 99%. We also demonstrate that this 2'-methylselenophosphoramidite is compatible with the 5'-silyl-2'-ACE chemistry, for longer Se-RNA solid-phase synthesis. Our preliminary NMR study on the synthesized 2'-Se-DNA has revealed a U(Se)-A base pair and a duplex structure formation when its complementary strand was present.
Assuntos
Desoxiuridina/análogos & derivados , Oligonucleotídeos/química , Compostos Organofosforados/síntese química , Compostos Organosselênicos/síntese química , Uridina/análogos & derivados , Desoxiuridina/síntese química , Desoxiuridina/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Compostos Organosselênicos/química , Uridina/síntese químicaRESUMO
UNLABELLED: Pharmacologic modulation of 5-fluorouracil (5-FU) metabolism provides a possibility for the enhancement of its clinical efficacy. AIM: The purpose of the present work was to study the effect of 5-ethyl-2'-deoxyuridine (EUdR), a potent 5-FU modulator, on different molecular mechanisms, influenced by 5-FU itself, and to obtain further data about the mode of action of the combination. MATERIALS AND METHODS: SW620 cell line was used for the experiments. Cytotoxicity was studied by MTT test, cell kinetic changes by FACStar flow cytometer, apoptosis by fluorescent microscope after staining the cells with acridine orange and ethydium bromide, DNA fragmentation by PAGE electrophoresis after RNase and proteinase-K digestion, thymidine incorporation with 3H-thymidine, p53 and PCNA protein expression by Western blotting. RESULTS: The cytotoxicity of 5-FU was potentiated dose dependently by EUdR. One hundred muM concentration of EUdR resulted in a 40% decrease of the IC50 value of 5-FU. Cell cycle arrest in the G2/M transition phase was most pronounced after combined treatment with 5-FU+EUdR. EUdR potentiated the incorporation of 3Hthymidine into DNA. In addition to the increase of apoptosis rate, the expression of p53 protein, caused by 5-FU was further potentiated by UdR. CONCLUSION: This study demonstrated a potential novel approach to increase the efficacy of 5-FU by EUdR, which incorporated two complementary molecular actions, the selective modulation of TS inhibition and potentiation of the p53 protein expression, consequently leading to an increase in the apoptotic rate.
Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Desoxiuridina/análogos & derivados , Desoxiuridina/farmacologia , Fluoruracila/farmacologia , Apoptose , Western Blotting , Linhagem Celular Tumoral , Fragmentação do DNA , Sinergismo Farmacológico , Eletroforese em Gel de Poliacrilamida , Citometria de Fluxo , Humanos , Microscopia de Fluorescência , Antígeno Nuclear de Célula em Proliferação/análise , Fatores de Tempo , Proteína Supressora de Tumor p53/análiseRESUMO
An isolated ribonuclease H domain of HIV-1 reverse transcriptase is capable of specifically removing the tRNA primer within an oligonucleotide mimic. The determinants for substrate specificity are located in a region within the terminal octanucleotide of the acceptor stem of the tRNA. Recognition of the substrate by HIV-1 RNase H was analyzed by the introduction of a cross-linking reagent directed toward lysines on the thymine residue complementary to the scissile bond, facing the major groove of the DNA-RNA:DNA substrate. Cross-linking of the modified substrate to RNase H required the presence of Mn(2+). The Mn(2+) titration of cross-linking paralleled the Mn(2+) requirement for activity. Modified substrate quenched with glycine prior to binding of substrate was efficiently cleaved, whereas the RNA within the cross-linked product was intact. Tryptic digestion of the isolated RNase H-nucleic acid covalent complex revealed a main cross-linked peptide whose N-terminal peptide sequence is VVTLTDTTNQ, indicating that the cross-linked lysine corresponds to Lys476. Cross-linking to K476 was confirmed by analysis of K476C RNase H. Mutation of K476C disrupted the chemical cross-linking while maintaining activity. On the basis of the size of the cross-linker arm, the results indicate that K476 is in closer proximity to the tRNA mimic substrate within the isolated RNase H domain than observed for the RNase H-resistant polypurine tract (PPT) substrate within the HIV-1 RT.
Assuntos
Reagentes de Ligações Cruzadas/química , DNA Viral/química , Desoxiuridina/análogos & derivados , Transcriptase Reversa do HIV/química , Lisina/química , RNA Viral/química , Ribonuclease H/química , Ligação Competitiva , Catálise , DNA Viral/síntese química , Desoxiuridina/química , Hidrólise , Cinética , Manganês/química , Compostos Organofosforados/química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Estrutura Terciária de Proteína , RNA Viral/síntese química , Ribonuclease H/isolamento & purificação , Especificidade por Substrato , Succinimidas/químicaRESUMO
5-(3-Perylenylethynyl)-2'-deoxyuridine was prepared by cross-linking 5-iodo-2'-deoxyuridine derivatives with 3-ethynylperylene followed by deprotection. 5-(1-Perylenylethynyl)-, 5-(3-perylenylethynyl)-, and 5-[4-(2-benzoxazolyl)phenylethynyl]-2'-deoxyuridine were found to inhibit in Vero cells the replication of type 1 herpes simplex virus and its drug-resistant strains.
Assuntos
Antivirais/química , Antivirais/farmacologia , Desoxiuridina/química , Animais , Células Cultivadas , Química Orgânica/métodos , Reagentes de Ligações Cruzadas/química , Desoxiuridina/análogos & derivados , Avaliação Pré-Clínica de Medicamentos/métodos , Farmacorresistência Viral Múltipla , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 1/fisiologia , Rim/citologia , Rim/efeitos dos fármacos , Rim/virologia , Perileno/análogos & derivados , Perileno/química , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacosRESUMO
The development of low molecular weight inhibitors of hepatitis C virus (HCV) replication has been hindered by the lack of a good cell-based system that models the entire HCV replication cycle. To date the only two therapies approved for the treatment of HCV infection are interferon (IFN)-alpha and the nucleoside analogue, ribavirin. We have created a cell-based system that allows for the accurate quantification of the replication of an HCV-like RNA template by proteins that are encoded for by the HCV genome. The system consists of a cell line that constitutively produces luciferase in response to the production of functional HCV replicative proteins. The 293B4alpha cell line has been formatted into a semi-high throughput, cell-based screen for inhibitors of HCV replication. When these cells were treated with either IFN-alpha or -beta, luciferase production decreased in a dose-responsive manner. Counterscreening these molecules in another cell line, 293SVLuc, in which luciferase production in not dependent the presence of functional HCV proteins, showed that the inhibition of luciferase in the 293B4alpha cell line was due to inhibition of the replication of the HCV-like RNA template and not anti-cellular or -luciferase activity. Moreover, when the 293B4alpha cell line was treated with the ribonucleoside analogue, 3'-deoxycytidine, luciferase decreased in a dose-responsive manner. 3'-deoxyguanosine and 3'-deoxyuridine did not inhibit luciferase production and 3'-deoxyadenosine was too cytotoxic to determine if it had any anti-HCV activity.
Assuntos
Antivirais/farmacologia , Desoxicitidina/farmacologia , Hepacivirus/efeitos dos fármacos , Interferon-alfa/farmacologia , Interferon beta/farmacologia , RNA Viral/biossíntese , Replicação Viral/efeitos dos fármacos , Linhagem Celular/virologia , Desoxiadenosinas/farmacologia , Desoxicitidina/análogos & derivados , Desoxiguanosina/análogos & derivados , Desoxiguanosina/farmacologia , Desoxiuridina/análogos & derivados , Desoxiuridina/farmacologia , Relação Dose-Resposta a Droga , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Genes Reporter , Células HeLa/virologia , Hepacivirus/genética , Hepacivirus/fisiologia , Hepatócitos/virologia , Humanos , Rim , Luciferases/biossíntese , Luciferases/genética , RNA Viral/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Ribavirina/farmacologia , Moldes GenéticosRESUMO
This study evaluated the effects of vitamin E (alpha-tocopherol) on oxidative DNA damage in a randomized double-blind Phase II chemoprevention trial. Oxidative DNA damage was measured by the level of auto-antibody (Ab) against 5-hydroxymethyl-2'-deoxyuridine (HMdU) in plasma. After the baseline screening, eligible subjects (n = 31; plasma samples from 28 subjects were available for this study) were randomized to receive 15, 60, or 200 mg of alpha-tocopherol per day for 28 days. Biomarkers were measured twice at baseline--on day 1 (visit 1) and day 3 (visit 2)--and twice after intervention--on day 17 (visit 3) and day 31 (visit 4). At baseline, there was a highly significant inverse correlation between anti-HMdU Ab titer and plasma vitamin E level (r = -0.53; P = 0.004; n = 28). Smoking did not affect baseline anti-HMdU Ab titer; however, anti-HMdU Ab titer levels at baseline were significantly lower in subjects with above-median (0.75 ounce/day) alcohol consumption (P = 0.008). No significant change in anti-HMdU Ab level occurred at either visit 3 or visit 4 for subjects on the lowest dose, 15 mg alpha-tocopherol per day. Subjects receiving 60 mg of alpha-tocopherol per day had a significant decrease in anti-HMdU Ab level at visits 3 and 4 compared with baseline (P = 0.049 and P = 0.02, respectively). However, subjects receiving the highest dose, 200 mg/day, had less consistent results: a significant decrease in anti-HMdU Ab level was seen at visit 4 (P = 0.04) but not at visit 3. Our results demonstrate an inverse relationship between alpha-tocopherol and anti-HMdU Abs in plasma; oxidative DNA damage can be modulated by short-term dietary supplementation of alpha-tocopherol in some subjects.
Assuntos
Autoanticorpos/análise , Dano ao DNA , Reparo do DNA , Desoxiuridina/análogos & derivados , Vitamina E/farmacologia , Adulto , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/prevenção & controle , Espécies Reativas de Oxigênio , Vitamina E/uso terapêuticoRESUMO
A novel nucleic acid model that possessed 5'-amino-5'-deoxyuridine at alpha- and gamma-position of L-glutamic acid through amide linkage using 5'-amino group was synthesized and the conformation and the hybridization properties were studied. The complex of alpha-PRNA with complementary DNA/RNA was more stable than the corresponding natural duplex in the absence of borate. Its recognition ability was however lost when borax was added to the solution.
Assuntos
DNA/química , Conformação de Ácido Nucleico , Ácidos Nucleicos Peptídicos/química , RNA/química , Boratos , Desoxiuridina/análogos & derivados , Ácido Glutâmico , Indicadores e Reagentes , Cinética , Modelos Moleculares , Hibridização de Ácido NucleicoRESUMO
PURPOSE: To investigate the possible benefit of hyperthermia (HT) in combination with radiosensitization by halogenated pyrimidines (HPs) in rodent as well as in human tumor cells. METHODS AND MATERIALS: Exponentially growing rodent cells, radiosensitive R-1 and MOS cells and radioresistant RUC-II and V79 cells, and human SW1573 cells, were exposed to 0, 1, 2, and 4 microM of chloro- (CldUrd), bromo- (BrdUrd), or iodo-deoxyuridine (IdUrd) in the culture medium. Survival after irradiation with gamma-rays from a 137Cs source and/or hyperthermic treatment (HT, 60 min at 42 degrees C) was determined by clonogenic assay. Linear-quadratic analyses of the radiation survival curves were performed to assess sensitization in the dose range 1 to 3 Gy relevant to radiotherapy. RESULTS: The incorporation of HPs sensitized all cell lines to HT and resulted in radiosensitization dependent on the percentage of thymidine replacement. At equal levels of thymidine replacement, IdUrd was the most potent radiosensitizer. HT further increased radiation-induced lethality of cells that had incorporated HPs. Linear-quadratic analyses showed that HT further increased the linear parameter of the LQ formula while the quadratic parameter was not significantly changed. CONCLUSION: The combination of HT and HPs act additively in increasing the radiosensitivity of rodent tumor cell lines with varying radiosensitivities as well as of a human tumor cell line. In particular, the ratio of the linear parameter to the quadratic parameter, relevant for fractionation effects in radiotherapy, was increased.
Assuntos
Desoxiuridina/análogos & derivados , Desoxiuridina/farmacocinética , Hipertermia Induzida , Radiossensibilizantes/farmacocinética , Animais , Bromodesoxiuridina/farmacocinética , Sobrevivência Celular/efeitos da radiação , Terapia Combinada , Cricetinae , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Idoxuridina/farmacocinética , Ratos , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/efeitos da radiaçãoRESUMO
Parenteral administration of an inhibitor of chymotrypsin-like proteases (TPCK) to mice infected with alphavirus (Sindbis AR/339 strain) blocked virus replication in the brain and inhibited the development of viremia in the infected animals. The most likely mechanism of TPCK antiviral effect seems to consist in disturbance of proteolytic processing of viral proteins.
Assuntos
Quimotripsina/antagonistas & inibidores , Desoxiuridina/análogos & derivados , Inibidores de Proteases/uso terapêutico , Infecções por Togaviridae/tratamento farmacológico , Replicação Viral/efeitos dos fármacos , Animais , Encéfalo/microbiologia , Desoxiuridina/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Camundongos , Sindbis virus/efeitos dos fármacos , Sindbis virus/fisiologia , Fatores de Tempo , Infecções por Togaviridae/microbiologia , Viremia/tratamento farmacológico , Viremia/microbiologiaRESUMO
The adenosine deaminase-resistant purine deoxynucleoside 2-chloro-2'-deoxyadenosine (CdA) is markedly toxic in vitro to nondividing and proliferating normal human lymphocytes and to many leukemia cell specimens. The CdA is also effective against mouse L1210 leukemia in vivo. The present investigations have examined the pharmacology, chemotherapeutic activity, and toxicity of CdA in nine patients with advanced hematologic malignancies refractory to conventional therapy. When administered by continuous intravenous infusion, the deoxyadenosine analog was well tolerated. As monitored by radioimmunoassay, plasma CdA levels rose gradually during the infusions. The CdA was not deaminated significantly. In all patients with leukemia, the CdA lowered the blast count by at least 50%. In one patient with a T-cell leukemia-lymphoma, and in another patient with chronic myelogenous leukemia in blast crisis, the CdA infusion eliminated all detectable blasts from the blood and bone marrow. In a patient with a diffuse lymphoma complicated by severe autoimmune hemolytic anemia, CdA treatment quickly terminated the hemolytic process. Bone marrow suppression represented the dose-limiting toxicity, and was related to plasma CdA levels, cumulative drug dosage, and the rapid release of CdA that accompanied tumor cell lysis.
Assuntos
Desoxiuridina/análogos & derivados , Imunossupressores , Leucemia/tratamento farmacológico , Linfoma/tratamento farmacológico , Animais , Medula Óssea/efeitos dos fármacos , Desoxiuridina/sangue , Desoxiuridina/síntese química , Desoxiuridina/toxicidade , Avaliação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Isomerismo , Leucemia L1210/tratamento farmacológico , Camundongos , RadioimunoensaioRESUMO
Rapid and efficient syntheses for the preparation of 2'-deoxy-5-vinyluridine and 2'-deoxy-5-vinylcytidine are described starting from nucleoside precursors. Contrary to some previous reports, 2-deoxy-5-vinyluridine has be found to be quite stable under normal laboratory conditions but when tested in animals shows neither toxicity nor anti-leukemic (L1210 cells) or anti-parasitic (Plasmodium berghei) activity. 2'-Deoxy-5-vinylcytidine appears to polymerise readily. It is much less toxic to cell cultures than 2'-deoxy-5'vinyluridine but is almost as active against herpes virus replication (ID50:0.2 microgram/ml) for both type 1 and type 2 herpes virus (selectivity index:225).
Assuntos
Antivirais/síntese química , Desoxicitidina/análogos & derivados , Desoxiuridina/análogos & derivados , Animais , Antivirais/uso terapêutico , Desoxicitidina/síntese química , Desoxicitidina/uso terapêutico , Desoxiuridina/síntese química , Desoxiuridina/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Infecções por Herpesviridae/tratamento farmacológico , Leucemia L1210/tratamento farmacológico , Camundongos , Relação Estrutura-AtividadeRESUMO
The main categories of antiherpes agents presently used in chemotherapy area reviewed according to the phase of virus replication affected : 1) virus adsorption (adamantane, nonionic surfactants) ; 2) eclipse (interferon) ; 3) virion maturation (nucleoside and nucleotide analogues and phosphonic acid derivatives). Mention is also made of other compounds--different synthetic organic derivatives, photodynamic dyes, metal ions, boric acid, hormones, antibiotics, other natural products (extracts from marine algae, propolis, garlic)--with promising antiviral properties. The difficulties and prospects of viral chemotherapy research are briefly discussed.
Assuntos
Antivirais/uso terapêutico , Infecções por Herpesviridae/tratamento farmacológico , Aciclovir , Adamantano/uso terapêutico , Amantadina/análogos & derivados , Amantadina/uso terapêutico , Animais , Arabinonucleosídeos/uso terapêutico , Bromodesoxiuridina/análogos & derivados , Bromodesoxiuridina/uso terapêutico , DNA Viral/metabolismo , Desoxiuridina/análogos & derivados , Desoxiuridina/uso terapêutico , Floxuridina/uso terapêutico , Guanina/análogos & derivados , Guanina/uso terapêutico , Herpesviridae/efeitos dos fármacos , Herpesviridae/metabolismo , Humanos , Idoxuridina/uso terapêutico , Interferons/uso terapêutico , Nucleosídeos/uso terapêutico , Nucleotídeos/uso terapêutico , Tensoativos/uso terapêuticoRESUMO
The problems encountered in the synthesis of 5-vinyl-2'-deoxyuridine are outlined and the synthesis of 5-bromoethynyl-2'-deoxyuridine described. E-5-(2-Bromovinyl)-2'-deoxyuridine is the most potent and specific agent against some herpes viruses yet discovered; we have now synthesised the Z-isomer and this appears to be essentially biologically inert.