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1.
ESMO Open ; 6(3): 100106, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33865192

RESUMO

Squamous cell carcinomas (SCCs) are among the most frequent solid tumors in humans. SCCs, related or not to the human papillomavirus, share common molecular features. Immunotherapies, and specifically immune checkpoint inhibitors, have been shown to improve overall survival in multiple cancer types, including SCCs. However, only a minority of patients experience a durable response with immunotherapy. Epigenetic modulation plays a major role in escaping tumor immunosurveillance and confers resistance to immune checkpoint inhibitors. Preclinical evidence suggests that modulating the epigenome might improve the efficacy of immunotherapy. We herein review the preclinical and the clinical rationale for combining immunotherapy with an epidrug, and detail the design of PEVOsq, a basket clinical trial combining pembrolizumab with vorinostat, a histone deacetylase inhibitor, in patients with SCCs of different locations. Sequential blood and tumor sampling will be collected in order to identify predictive and pharmacodynamics biomarkers of efficacy of the combination. We also present how clinical and biological data will be managed with the aim to enable the development of a prospective integrative platform to allow secure and controlled access to the project data as well as further exploitations.


Assuntos
Alphapapillomavirus , Carcinoma de Células Escamosas , Carcinoma de Células Escamosas/tratamento farmacológico , Humanos , Imunoterapia , Papillomaviridae , Estudos Prospectivos
2.
Climacteric ; 10 Suppl 2: 47-53, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17882673

RESUMO

We have developed a new approach for breast cancer prevention, capitalizing in the preventive effect of early first full-term pregnancy, hormonally induced differentiation and our ability to identify specific genomic signatures that allow us to predict risk reduction. Early pregnancy imprints in the breast permanent genomic changes or a 'signature' that reduces the susceptibility of this organ to cancer. At cellular level, what we have achieved is the shifting of the Stem Cell 1 population, highly susceptible to cancer, to a population of Stem Cell 2 that is refractory to carcinogenesis. In a case-control study, we have compared the gene expression profile in normal breast tissue from nulliparous and parous postmenopausal women with (case) and without (control) breast cancer. We have determined that early first full-term pregnancy induces a specific genomic signature in the postmenopausal breast that is the biomarker for the Stem cell 2. The Stem cell 2 contains specific genes controlling transcription, RNA processing, immune response, apoptosis and DNA repair. We have further detected in the plasma, using an ELISA assay, the proteins coded by the gene signature. We are developing clinical trials to demonstrate the proof of the principle that r-hCG can induce in the human breast a genomic signature of the Stem cell 2. This is a concept that challenges the currently available chemopreventive agents that need to be given for extended periods for maintaining the suppression of a specific metabolic pathway or the abrogation of the function of an organ.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/prevenção & controle , Mama/citologia , Diferenciação Celular/genética , Transformação Celular Neoplásica/genética , Células Epiteliais/citologia , Paridade , Mama/fisiologia , Estudos de Casos e Controles , Transformação Celular Neoplásica/patologia , Suscetibilidade a Doenças , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Mucosa Bucal/citologia , Pós-Menopausa , Gravidez , RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco
3.
Int J Oncol ; 31(2): 303-12, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17611686

RESUMO

Endocrine and reproductive influences significantly affect the lifetime risk of breast cancer. Nulliparity is one of the most firmly established risk factors for breast cancer, whereas early full-term pregnancy and parity confer a significant protection. The breast attains its maximum development during pregnancy and lactation. After menopause the breast regresses in both nulliparous and parous women containing lobular structures designated lobules type 1 (Lob 1). We have postulated that the degree of differentiation acquired through early pregnancy changes the 'genomic signature' that differentiates the Lob 1 from the early parous women from that of the nulliparous women by shifting the Stem cell 1 to a Stem cell 2, making this the mechanism of protection conferred by early full-term pregnancy. In order to elucidate the molecular pathways through which pregnancy exerts a protective effect, we have analyzed the genomic profile of Lob 1 present in reduction mammoplasty specimens obtained from parous and nulliparous postmenopausal women. The genes differentially expressed are related to immune-surveillance, DNA repair, programmed cell death, transcription, and chromatin structure/activators/co-activator. In the present study we performed real-time RT-PCR using a low-density array or a microfluid card for genes related to the immune system and programmed cell death, using 18S as an internal control [TaqMan(R) Low Density Array Human Immune Panel (Applied Biosystems)]. Breast epithelial cells from parous women significantly overexpressed 17 out of 20 genes (p<0.001) with respect to the nulliparous breast. BCL2-associated X protein, Complement component 3, CD45 antigen, glyceraldehyde-3-phosphate dehydrogenase, granulysin, and chemokine (C-C motif) ligand 19 were expressed more than 30-fold with respect to nulliparous breast cells. Only three out of 20 genes [selectin P (granule membrane protein 140 kDa, antigen CD62), Fas (TNF receptor superfamily, member 6) and chemokine (C-X-C motif) ligand 11], were downregulated in parous breast with respect to nulliparous breast cells. The data lead us to conclude that an early pregnancy, by shifting the Stem cell 1 to Stem cell 2, makes the latter more easily recognized by the immune-surveillance system, which initiates the programmed cell death pathway if exposure to toxic or carcinogenic agents occurs.


Assuntos
Mama/metabolismo , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Sistema Imunitário , Adulto , Morte Celular , Diferenciação Celular , Feminino , Humanos , Pessoa de Meia-Idade , Modelos Biológicos , Paridade , Pós-Menopausa , Gravidez , Células-Tronco/metabolismo
4.
Int J Oncol ; 29(4): 877-81, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16964383

RESUMO

Breast cancer is the most frequent malignancy in women. It is well recognized that tumorigenesis is a multistep process resulting from the accumulation of sequential genetic alterations. In breast cancers LOH has been described on one or both arms of multiple chromosomes. Comparative genomic hybridization (CGH) analysis was performed to identify chromosomal imbalances in the breast epithelial cells (HBEC). We have used a human in vitro-in vivo system in which the environmental carcinogen benz(a)pyrene (BP) and the c-Ha-ras oncogene were utilized for inducing in vitro transformation of HBEC. Immortal MCF-10F cells were treated with BP which resulted in the transformed cell line BP-1 that was further enhanced by transfection with the c-Ha-ras to generate the cell line BP-1-Tras. This cell line is tumorigenic when injected in severe combined immunodeficient (SCID) mice, generating the tumor cell line BP-1-Tras T J#4. Our comparative genomic hybridization analysis indicates that the most overrepresented segment after cell transformation and in the BP-1, BP-1-Tras and in the tumor cell line were 1p (80%), 5q21-ter (80%), 8q24.1 (90%) and Xq27-28 (60%). DNA sequence amplification at 10p14-15 was observed in BP-1-Tras T J#4 cells. Allelic losses of chromosome 4, 8p11-21 and 15q11-12, occur after cell transformation and are maintained consistently during tumorigenesis.


Assuntos
Neoplasias da Mama/genética , Transformação Celular Neoplásica/genética , Aberrações Cromossômicas , Animais , Benzopirenos/toxicidade , Mama/efeitos dos fármacos , Neoplasias da Mama/induzido quimicamente , Linhagem Celular Transformada , Linhagem Celular Tumoral , Transformação Celular Neoplásica/induzido quimicamente , Aberrações Cromossômicas/induzido quimicamente , Cromossomos Humanos/efeitos dos fármacos , Cromossomos Humanos/genética , Análise Citogenética , Células Epiteliais/efeitos dos fármacos , Feminino , Genes ras/genética , Humanos , Camundongos , Camundongos SCID , Hibridização de Ácido Nucleico
5.
Int J Oncol ; 28(4): 995-1002, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16525651

RESUMO

p53 wild-type is a tumor suppressor gene involved in DNA gene transcription or DNA repair mechanisms. When damage to DNA is unrepairable, p53 induces programmed cell death (apoptosis). The mutant p53 gene is the most frequent molecular alteration in human cancer, including breast cancer. Here, we analyzed the genetic alterations in p53 oncogene expression in 55 patients with breast cancer at different stages and in 8 normal women. We measured by ELISA assay the serum levels of p53 mutant protein and p53 antibodies. Immunohistochemistry and RT-PCR using specific p53 primers as well as mutation detection by DNA sequencing were also evaluated in breast tumor tissue. Serological p53 antibody analysis detected 0/8 (0%), 0/4 (0%) and 9/55 (16.36%) positive cases in normal women, in patients with benign breast disease and in breast carcinoma, respectively. We found positive p53 mutant in the sera of 0/8 (0.0%) normal women, 0/4 (0%) with benign breast disease and 29/55 (52.72%) with breast carcinoma. Immunohistochemistry evaluation was positive in 29/55 (52.73%) with mammary carcinoma and 0/4 (0%) with benign breast disease. A very good correlation between p53 mutant protein detected in serum and p53 accumulation by immunohistochemistry (83.3% positive in both assays) was found in this study. These data suggest that detection of mutated p53 could be a useful serological marker for diagnostic purposes.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/patologia , Mutação , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/sangue , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/imunologia , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Carcinoma in Situ/sangue , Carcinoma in Situ/genética , Carcinoma in Situ/patologia , Carcinoma Ductal de Mama/sangue , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteína Supressora de Tumor p53/sangue , Proteína Supressora de Tumor p53/imunologia
6.
Mol Endocrinol ; 18(9): 2333-43, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15192074

RESUMO

We have investigated the molecular mechanisms involved in 17 beta-estradiol-induced angiogenic pathway. We show here that 17 beta-estradiol promoted a 6-fold increase in Jagged1 expression and an 8-fold increase in Notch1 expression by cDNA arrays in breast cancer MCF7 cells. Interestingly, Jagged1 was abrogated by incubation with the estrogen antagonist, ICI182,780. A similar up-regulation of both Notch1 receptor and Jagged1 ligand was found in endothelial cells. Additionally, imperfect estrogen-responsive elements were found in the 5' untranslated region of Notch1 and Jagged1 genes. Treatment with 17 beta-estradiol also led to an activation of Notch signaling in MCF7 cells expressing Notch1 reporter gene or by promoting Jagged1-induced Notch signaling in coculture assays. Inoculation of MCF7 cells in 17 beta-estradiol-treated nude mice resulted in up-regulation of Notch1 expression as well as increased number of tumor microvessels in comparison to placebo-treated mice. Notch1-expressing endothelial cell cultures formed cord-like structures on Matrigel in contrast to cells expressing a dominant-negative form of Notch1, emphasizing the relevance of Notch1 pathway in vessel assembly. Finally, Notch1-expressing MCF7 cells up-regulated hypoxia-inducible factor 1 alpha gene, a well-known angiogenic factor that clustered with Notch1 gene. This study implicates Notch signaling in the cross talk between 17 beta-estradiol and angiogenesis.


Assuntos
Neoplasias da Mama/irrigação sanguínea , Estrogênios/fisiologia , Neovascularização Patológica/genética , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Animais , Neoplasias da Mama/metabolismo , Proteínas de Ligação ao Cálcio , Linhagem Celular Tumoral , Estrogênios/farmacologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Proteína Jagged-1 , Proteínas de Membrana/genética , Camundongos , Transplante de Neoplasias/fisiologia , Neovascularização Patológica/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Receptor Notch1 , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/fisiologia , Proteínas Serrate-Jagged , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Regulação para Cima
7.
Mol Genet Genomics ; 271(2): 171-9, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14758542

RESUMO

Cytochrome c heme lyases encoded by the Sinorhizobium meliloti cycHJKL operon are responsible for generating the covalent bond between the heme prosthetic group and apocytochromes c. The CycH protein with its presumably membrane-associated N-terminal and periplasmic C-terminal parts is thought to be responsible for binding apocytochrome and presenting it to the heme ligation machinery. We propose that these two modules of CycH play roles in different functions of the protein. The N-terminal 96 amino acids represent an active subdomain of the protein, which is able to complement the protoporphyrin IX (PPIX) accumulation phenotype of the cycH mutant strain AT342, suggesting that it is involved in the final steps of heme C biosynthesis. Furthermore, three tetratricopeptide (TPR) domains have been identified in the C-terminal periplasmic region of the CycH protein. TPR domains are known to mediate protein-protein interactions. Each of these CycH domains is absolutely required for protein function, since plasmid constructs carrying cycH genes with in-frame TPR deletions were not able to complement cycH mutants for their nitrate reductase (Rnr-) and nitrogen-fixing (Fix-) phenotypes. We also found that the 309-amino acid N-terminal portion of the CycH, which includes all the TPR domains, is able to mediate the assembly of the c-type cytochromes required for the Rnr+ phenotype. In contrast, only the full-length protein confers the ability to fix nitrogen.


Assuntos
Proteínas de Bactérias/metabolismo , Citocromos c/biossíntese , Heme/metabolismo , Proteínas de Membrana/metabolismo , Sinorhizobium meliloti/genética , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Citocromos c/genética , Primers do DNA , Escherichia coli/genética , Proteínas de Membrana/genética , Dados de Sequência Molecular , Plasmídeos/genética , Estrutura Terciária de Proteína/genética , Alinhamento de Sequência , Análise de Sequência de DNA , beta-Galactosidase
8.
J Pharm Biomed Anal ; 29(6): 1153-7, 2002 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-12110402

RESUMO

The impurity profile of ethynodiol diacetate was investigated using the HPLC/UV/MS method. Using the slightly modified HPLC method of USP 24 two impurities, earlier isolated by preparative HPLC and investigated by NMR spectroscopy were separated and characterised. The mass spectra amended by the diode-array UV spectra supported the earlier found structures (E and Z isomers of 17alpha-ethinyl-estr-4-ene-3beta,17-diol-3-acetate-17-(3'-acetoxy-2'-butenoate). Another, hitherto not described impurity, 17alpha-ethinyl-estr-4-ene-3beta,17-diol-3-acetate-17-(3-oxo-butanoate) has also been separated and characterised by means of its mass spectrum, NMR and UV spectra.


Assuntos
Anticoncepcionais Orais Sintéticos/análise , Contaminação de Medicamentos , Diacetato de Etinodiol/análise , Preparações Farmacêuticas/normas , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrofotometria Ultravioleta , Estereoisomerismo
9.
Magy Seb ; 54(4): 223-6, 2001 Aug.
Artigo em Húngaro | MEDLINE | ID: mdl-11550489

RESUMO

The authors present their experiences in treatment of chronic pancreatic abscess and infected pancreatic necrosis. In this paper they refer to patients only whose acute necrotizing pancreatitis occurred 4-6 weeks earlier and had intra- and peripancreatic abscesses. They describe their successful lavage method for treatment of pancreatic abscesses. Between 1985 and 1998 they treated 16 patients with only one mortality. The majority of their patients were relatively old and most of them suffered from several severe unrelated diseases. In their opinion, careful dissection and long period of lavage and drainage are a successful method for treating this high-risk surgical group.


Assuntos
Abscesso/terapia , Pancreatite/terapia , Abscesso/cirurgia , Doença Aguda , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/cirurgia , Cuidados Pós-Operatórios/métodos , Estudos Retrospectivos , Fatores de Risco , Irrigação Terapêutica , Resultado do Tratamento
10.
Proc Natl Acad Sci U S A ; 98(6): 3098-103, 2001 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-11248038

RESUMO

The small heat shock proteins (sHSPs) are ubiquitous stress proteins proposed to act as molecular chaperones to prevent irreversible protein denaturation. We characterized the chaperone activity of Synechocystis HSP17 and found that it has not only protein-protective activity, but also a previously unrecognized ability to stabilize lipid membranes. Like other sHSPs, recombinant Synechocystis HSP17 formed stable complexes with denatured malate dehydrogenase and served as a reservoir for the unfolded substrate, transferring it to the DnaK/DnaJ/GrpE and GroEL/ES chaperone network for subsequent refolding. Large unilamellar vesicles made of synthetic and cyanobacterial lipids were found to modulate this refolding process. Investigation of HSP17-lipid interactions revealed a preference for the liquid crystalline phase and resulted in an elevated physical order in model lipid membranes. Direct evidence for the participation of HSP17 in the control of thylakoid membrane physical state in vivo was gained by examining an hsp17(-) deletion mutant compared with the isogenic wild-type hsp17(+) revertant Synechocystis cells. We suggest that, together with GroEL, HSP17 behaves as an amphitropic protein and plays a dual role. Depending on its membrane or cytosolic location, it may function as a "membrane stabilizing factor" as well as a member of a multichaperone protein-folding network. Membrane association of sHSPs could antagonize the heat-induced hyperfluidization of specific membrane domains and thereby serve to preserve structural and functional integrity of biomembranes.


Assuntos
Cianobactérias/metabolismo , Proteínas de Choque Térmico/metabolismo , Malato Desidrogenase/metabolismo , Chaperonas Moleculares/metabolismo , Dobramento de Proteína , Membrana Celular , Cianobactérias/genética , Proteínas de Choque Térmico/genética , Calefação , Bicamadas Lipídicas/metabolismo , Metabolismo dos Lipídeos , Lipossomos/metabolismo , Fluidez de Membrana , Chaperonas Moleculares/genética , Desnaturação Proteica , Tilacoides/metabolismo
11.
Lipids ; 35(10): 1093-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11104015

RESUMO

The compositions of lipid classes as well as the molecular species composition of subclasses (diacyl, alkylacyl, and alkenylacyl forms) of choline and ethanolamine phosphoglycerides in marine amphipod crustaceans, Gammarus spp., collected in the Baltic Sea at 8 and 15 degrees C, were studied in relation to environmental temperature. The structural order of phospholipid multibilayers was also determined. Environmental temperature had little effect on fatty acid composition. The level of some polyunsaturated fatty acids, such as 20:4, even increased in choline and ethanolamine phosphoglycerides at 15 degrees C. Ethanolamine phosphoglycerides were rich in alkenylacyl forms, especially in crustaceans collected at 15 degrees C. The accumulation of sn-1 monoenic, sn-2 polyenic diacyl, alkyl, and alkenylacyl phosphatidylethanolamines and diacyl phosphatidylcholines was observed at 8 degrees C. The phospholipid vesicles of crustaceans collected at 8 degrees C were more disordered than expected compared to those obtained from animals collected at 15 degrees C. It was concluded that, in addition to variations in the levels of sn-1 monoenic and sn-2 polyenic phospholipid molecular species with temperature, ethanolamine plasmalogens may play a role in controlling membrane biophysical properties in marine amphipod crustaceans.


Assuntos
Crustáceos/metabolismo , Fosfolipídeos/química , Animais , Fenômenos Biofísicos , Biofísica , Meio Ambiente , Polarização de Fluorescência , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Espectrometria de Fluorescência , Temperatura
12.
J Cell Biochem ; 79(4): 686-94, 2000 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-10996858

RESUMO

We have previously shown that the steroid hormone 1, 25-dihydroxy-vitamin D(3) [1,25(OH)(2)D(3)] stimulates total cell protein kinase C (PKC) activity in rat duodenum, an effect that is severely impaired in old animals. We further examined the role of 1, 25(OH)(2)D(3) on PKC as it relates to aging by measuring hormone-induced changes in subcellular localization of PKC activity and isoenzymes in duodenal mucosae from young (three-month-old) and aged (24-month-old) rats. Short treatment of duodenum with 1, 25(OH)(2)D(3) (0.1 nM, 1 min) increased membrane-associated PKC activity, whereas it decreased the activity in the cytosol of young rats but was without significant effect in aged animals. Furthermore, the ability to translocate was present in young animals after a short treatment with the phorbol ester 12-O-tetradecanoyl phorbol 13-acetate (TPA; 100 nM) or dioctanoyl-glycerol (50 microM), whereas the ability was absent in aged rats, suggesting that PKC function was impaired with aging independent of agonist stimulation. The expression of specific PKC isoenzymes and changes in their subcellular distribution after short exposure of the duodenum to the hormone were determined. Western blot analysis of total homogenates using antibodies to various PKC isoforms allowed detection of PKC alpha, beta, and delta. The expression of the straight theta and the zeta isoforms was in addition demonstrated by reverse transcription-polymerase chain reaction. The pattern of isoenzymes present in the duodenum was unaffected by aging. In young rats, 1, 25(OH)(2)D(3) translocates PKC alpha, beta, and delta to the membrane and nucleus; however, no translocation of PKC isoforms was observed in 24-month-old animals in response to the hormone. In summary, in rat duodenum, 1,25(OH)(2)D(3) modulation of PKC activity and isoenzyme subcellular distribution are impaired with aging and may explain age-induced alterations in the intestinal processes under the control of the hormone.


Assuntos
Envelhecimento/metabolismo , Calcitriol/farmacologia , Duodeno/efeitos dos fármacos , Duodeno/enzimologia , Proteína Quinase C/metabolismo , Envelhecimento/genética , Animais , Sequência de Bases , Primers do DNA/genética , Expressão Gênica , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/enzimologia , Isoenzimas/genética , Isoenzimas/metabolismo , Proteína Quinase C/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Frações Subcelulares/enzimologia
13.
Bioorg Med Chem Lett ; 10(15): 1775-7, 2000 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-10937746

RESUMO

A chemical model for the H2O2 promoted oxidation by nitric oxide synthase (NOS) has been developed. Biomimetic oxidations were carried out using H2O2 and tetrakis(perfluorophenyl)porphyrinato-iron(III) chloride (FeTPPF20) as a catalyst. Similarly to NOS our model system produces Ndelta-cyanoornithine, citrulline and NO from NOHA and did not oxidize arginine itself. Based on these results we propose a peroxide shunt to be involved in the catalytic cycle of NOS. To the best of our knowledge this is the first chemical system that semiquantitatively mimics NOS activity.


Assuntos
Guanidinas/química , Peróxido de Hidrogênio/metabolismo , Metaloporfirinas/química , Óxido Nítrico Sintase/metabolismo , Catálise , Hidroxilaminas , Modelos Químicos , Mimetismo Molecular , Oxirredução
14.
Steroids ; 65(5): 266-74, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10751638

RESUMO

The progestational activity of second- and third-generation progestins in oral contraceptives were markedly increased by addition of an 18-methyl group. A new progestin, the 18-methyl analog of Nestorone, 16-methylene-17alpha-hydroxy-18-methyl-19-norpregn-4-ene-3,2 0-dione acetate (10), was synthesized. The relative binding affinity and biologic activity of 10 was compared with Nestorone, levonorgestrel, and progesterone using a binding assay for rat progesterone receptors, the Clauberg assay in the rabbit, and by assessing pregnancy maintenance in the rat. These studies, as summarized in Table 4, show that 10 is three to ten times more potent than Nestorone. The addition of the 18-methyl group to Nestorone markedly increased its potency as noted above, but is unlikely to change its rate of delivery from sustained release systems. 10 should be ideally suited for administration by implants or small skin patches.


Assuntos
Norprogesteronas/síntese química , Norprogesteronas/farmacologia , Animais , Bioensaio , Anticoncepcionais Femininos/farmacologia , Relação Dose-Resposta a Droga , Endométrio/efeitos dos fármacos , Feminino , Levanogestrel/farmacologia , Masculino , Gravidez , Manutenção da Gravidez/efeitos dos fármacos , Progesterona/análogos & derivados , Progesterona/farmacologia , Congêneres da Progesterona/síntese química , Congêneres da Progesterona/farmacologia , Coelhos , Ratos , Ratos Sprague-Dawley
15.
J Biomol Struct Dyn ; 17(4): 759-67, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10698112

RESUMO

Similar to nitric oxide synthase (NOS) cytochrome P450 isoforms (e.g. 3A and 4E) can produce nitric oxide from arginine. Although the active site of both proteins contains a protoporphyrin IX unit having an axial cystein ligand, their effectiveness in the synthesis of NO differs significantly. Now the molecular basis of this functional difference was investigated. A homology model for cytochrome P450 3A4 was refined and compared to the X-ray structure of iNOS. We found the active site of iNOS to be more readily accessible for the substrate than that of P450. Docking calculations were performed using the Monte Carlo conformational analysis technique on all internal and external degrees of freedom of arginine and active site residues as well. The lowest energy conformation of the cytochrome P450 3A4-substrate complex was compared to the high resolution X-ray structure of the iNOS-arginine complex. Comparison of substrate orientations revealed that arginine binds in a similar conformation in both enzymes. In contrast to iNOS we found, however, that in P450 partially negative propionate side chains of protoporphyrin IX are located on the opposite side of the heme plane. As a result of this and the absence of other negatively charged residues the distal (substrate binding) side of P450 should be less negative than that of NOS and therefore its affinity toward the partially positive arginine is reduced. Comparison of molecular electrostatic potentials calculated within the active site of the proteins supports this proposal. Reduced affinity in combination with limited substrate access might be responsible for the less effective NO synthesis of cytochrome P450 observed experimentally.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Óxido Nítrico/biossíntese , Arginina/metabolismo , Catálise , Simulação por Computador , Cristalografia por Raios X , Modelos Moleculares , Método de Monte Carlo , Óxido Nítrico/química , Óxido Nítrico Sintase/química , Óxido Nítrico Sintase Tipo II , Isoformas de Proteínas , Eletricidade Estática
16.
Magy Seb ; 53(4): 146-50, 2000 Aug.
Artigo em Húngaro | MEDLINE | ID: mdl-11300058

RESUMO

We have performed 16 operations on 14 patients with primary hyperparathyoidism caused by a solitary parathyroid adenoma in our department between 1st jan. 1990-31 dec. 1999. In each case bilateral neck exploration was carried out. As in one case it was located in ectopic neck position, in the other case papillocarcinoma of the thyroid gland and ectopic parathyroid adenoma in mediastinal position were present, primary hyperparathyroidism persisted, so reoperation was needed. Histological examination proved the presence of adenomin all cases. Diffuse hyperplasia and parathyroid cancer did not occur. Before operation all patients underwent US and seven of them had radionuclide scintigraphy. CT scan aided in its localization with four patients. We did not make use of invasive methods, after the first operation 12 patients showed normal S-Ca levels very quickly. In two cases this level was too high after the operation and reoperation was necessary which resulted in normal Ca levels. Even though the number of our cases is rather modest, all the patients recovered. This may prove that we can successfully cure our patients of modern methods of diagnostics used for meticulous examination alongside with careful preparation of the patients by internal specialists are followed by the standard operative techniques available.


Assuntos
Adenoma/diagnóstico , Adenoma/cirurgia , Hiperparatireoidismo/cirurgia , Neoplasias das Paratireoides/diagnóstico , Neoplasias das Paratireoides/cirurgia , Paratireoidectomia , Adenoma/sangue , Adenoma/complicações , Adenoma/patologia , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Hiperparatireoidismo/sangue , Hiperparatireoidismo/diagnóstico , Hiperparatireoidismo/etiologia , Masculino , Pessoa de Meia-Idade , Neoplasias das Paratireoides/sangue , Neoplasias das Paratireoides/complicações , Neoplasias das Paratireoides/patologia , Paratireoidectomia/métodos , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
17.
Magy Seb ; 53(4): 151-4, 2000 Aug.
Artigo em Húngaro | MEDLINE | ID: mdl-11300059

RESUMO

The authors present their indications, aims and method for the local antibiotic treatment of chronic empyema thoracis. They analyse the sensitivity and resistant conditions of the most often occurring bacteria, Pseudomonas spp., in an open window treatment of empyema thoracis. 338 patients were treated for intrathoracic suppuration between January 1, 1987 and December 31, 1998. The youngest patient was 13, the oldest one was 90 (the average age was 53.2. Of these 11 died, representing a mortality rate of 3.2%. Of these 11 patients, 7 suffered from chronic intrathoracal suppuration. 82 patients had chronic empyema. 44 patients (13%) were treated by the open window procedure, 6 females and 38 males. The average age was 62.1. Of them 7 died, the mortality rate of chronic empyema thoracis was 8.5% in our department. Of 164 pus samples taken from suppurative pleura cavity bacteria, Pseudomonas spp., were bred in 148 cases during bacteriological examinations. Their bacteriological examinations confirm that local and aimed treatment by Polimyxin, Amikacin, Meronpenem, Ceftadizim, Imipenem, Tobramycin, Ciprofloxacin and Piperacillin proved to be the better medicine against Pseudomonas infection.


Assuntos
Antibacterianos/administração & dosagem , Empiema Pleural/tratamento farmacológico , Toracotomia , Administração Tópica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Drenagem , Empiema Pleural/microbiologia , Empiema Pleural/cirurgia , Feminino , Humanos , Instilação de Medicamentos , Masculino , Pessoa de Meia-Idade , Irrigação Terapêutica , Toracoscopia , Resultado do Tratamento
18.
Magy Seb ; 53(4): 160-2, 2000 Aug.
Artigo em Húngaro | MEDLINE | ID: mdl-11300062

RESUMO

The authors present their special surgical treatment by telling the medical history of one of their patients. Cessation of sternum protrusio was achieved by a "H" shape resection of the anterior cortical plate of the sternum.


Assuntos
Esterno/anormalidades , Esterno/cirurgia , Toracotomia/métodos , Adolescente , Humanos , Masculino , Resultado do Tratamento
19.
J Agric Food Chem ; 47(2): 762-9, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10563966

RESUMO

Cytochrome P450 (CP450) catalyzed oxidative metabolism of carbofuran (1), carbaryl (2), and pirimicarb (3) has been modeled using biomimetic oxidations catalyzed by iron(III) tetraarylporphyrins. Oxidation products of 1 were identified by comparison of HPLC retention times measured under standardized conditions for metabolites synthesized and characterized by (1)H and (13)C NMR spectroscopy. Comparison of product distributions to in vivo metabolic profiles revealed that the H(2)O(2)/meso-tetrakis(pentafluorophenyl)porphyrin iron(III) chloride [Fe(TF(20)PP)] system mimics the action of insect CP450s against carbofuran. The effectiveness of this system was further demonstrated by the biomimetic oxidation of other carbamate insecticides (2 and 3) monitored by HPLC/electrospray MS. The predictive power of this biomimetic model was compared to that of knowledge-based expert systems. Although similar models were recently applied in pharmaceutical research, the usefulness of this approach has first been demonstrated for the prediction of metabolic profiles of agrochemicals.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Inseticidas/metabolismo , Pirimidinas , Animais , Carbamatos/química , Carbaril/metabolismo , Moscas Domésticas/metabolismo , Espectroscopia de Ressonância Magnética , Oxirredução , Espectrofotometria Ultravioleta
20.
Exp Mol Pathol ; 67(2): 63-74, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10527758

RESUMO

As a first approach for studying the implication of PKC and the steroid hormone 1,25(OH)(2)-vitamin D(3) [1,25(OH)(2)D(3)] on natural killer cell (NK) activity, we analyzed in the YT NK cell line the expression of PKC isoforms and the effects of 1, 25(OH)(2)D(3) on BLT-esterase (a marker of NK lytic granules) activity. Western blot and RT-PCR showed a greater extent of PKC alpha, beta, delta, zeta, epsilon, theta, and lambda and lower levels of PKC mu and eta. In a dose-dependent manner 1, 25(OH)(2)D(3) induced significant increases in BLT-esterase and PKC activities and the stimulatory effect on BLT-esterase activity was mimicked and blocked, respectively, by the PKC activator phorbol ester PMA and PKC inhibitors (H7, PKC(19-36), and N-myristoylated PKC(19-31) peptides). Moreover, the effects of 1,25(OH)(2)D(3) on BLT-esterase could be blocked in a Ca(2+)-free (+EGTA) medium and mimicked by the Ca2+ ionophore A23187. The results suggest that 1, 25(OH)(2)D(3) is a stimulatory factor of NK activity acting through a mechanism involving PKC and extracellular Ca2+.


Assuntos
Calcitriol/farmacologia , Cálcio/metabolismo , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/metabolismo , Proteína Quinase C/metabolismo , Sequência de Bases , Calcimicina/farmacologia , Linhagem Celular , Primers do DNA/genética , Ácido Egtázico/farmacologia , Inibidores Enzimáticos/farmacologia , Espaço Extracelular/metabolismo , Expressão Gênica/efeitos dos fármacos , Granzimas , Humanos , Ionóforos/farmacologia , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Células Matadoras Naturais/imunologia , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina Endopeptidases/metabolismo , Frações Subcelulares/enzimologia , Acetato de Tetradecanoilforbol/farmacologia
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