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1.
J Assist Reprod Genet ; 39(8): 1693-1712, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35870095

RESUMO

Since 2007, the Oncofertility Consortium Annual Conference has brought together a diverse network of individuals from a wide range of backgrounds and professional levels to disseminate emerging basic and clinical research findings in fertility preservation. This network also developed enduring educational materials to accelerate the pace and quality of field-wide scientific communication. Between 2007 and 2019, the Oncofertility Consortium Annual Conference was held as an in-person event in Chicago, IL. The conference attracted approximately 250 attendees each year representing 20 countries around the world. In 2020, however, the COVID-19 pandemic disrupted this paradigm and precluded an in-person meeting. Nevertheless, there remained an undeniable demand for the oncofertility community to convene. To maintain the momentum of the field, the Oncofertility Consortium hosted a day-long virtual meeting on March 5, 2021, with the theme of "Oncofertility Around the Globe" to highlight the diversity of clinical care and translational research that is ongoing around the world in this discipline. This virtual meeting was hosted using the vFairs ® conference platform and allowed over 700 people to participate, many of whom were first-time conference attendees. The agenda featured concurrent sessions from presenters in six continents which provided attendees a complete overview of the field and furthered our mission to create a global community of oncofertility practice. This paper provides a synopsis of talks delivered at this event and highlights the new advances and frontiers in the fields of oncofertility and fertility preservation around the globe from clinical practice and patient-centered efforts to translational research.


Assuntos
COVID-19 , Preservação da Fertilidade , Neoplasias , COVID-19/epidemiologia , Humanos , Pandemias
3.
Cell Rep ; 42(7): 112730, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37453057

RESUMO

Cancer-associated mesothelial cells (CAMCs) in the tumor microenvironment are thought to promote growth and immune evasion. We find that, in mouse and human ovarian tumors, cancer cells express anti-Müllerian hormone (AMH) while CAMCs express its receptor AMHR2, suggesting a paracrine axis. Factors secreted by cancer cells induce AMHR2 expression during their reprogramming into CAMCs in mouse and human in vitro models. Overexpression of AMHR2 in the Met5a mesothelial cell line is sufficient to induce expression of immunosuppressive cytokines and growth factors that stimulate ovarian cancer cell growth in an AMH-dependent way. Finally, syngeneic cancer cells implanted in transgenic mice with Amhr2-/- CAMCs grow significantly slower than in wild-type hosts. The cytokine profile of Amhr2-/- tumor-bearing mice is altered and their tumors express less immune checkpoint markers programmed-cell-death 1 (PD1) and cytotoxic T lymphocyte-associated protein 4 (CTLA4). Taken together, these data suggest that the AMH/AMHR2 axis plays a critical role in regulating the pro-tumoral function of CAMCs in ovarian cancer.


Assuntos
Neoplasias Ovarianas , Hormônios Peptídicos , Feminino , Humanos , Animais , Camundongos , Hormônio Antimülleriano/genética , Neoplasias Ovarianas/genética , Camundongos Transgênicos , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Microambiente Tumoral
4.
Curr Mol Med ; 16(3): 222-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26917267

RESUMO

The MIS pathway is a potential therapeutic target in epithelial ovarian cancer (EOC): signaling requires both type II (T2R) and type I receptors (T1R), and results in growth inhibition. MISR2 is expressed in EOC, but the prevalence and relative contributions of candidate T1R remain unknown. We sought to: a) determine expression of T1R in EOC; b) assess impact of T1R expression with clinical outcomes; c) verify MIS-dependent Smad signaling and growth inhibition in primary EOC cell cultures. Tissue microarrays (TMA) were developed for analysis of T1Rs (ALK2/3/6) and MISR2 expression. Primary cell cultures were initiated from ascites harvested at surgery which were used to characterize response to MIS. TMA's from 311 primary cancers demonstrated the most common receptor combinations were: MISR2+/ALK2+3+6+ (36%); MISR2+/ALK2+3+6- (34%); MISR2-/ALK2+3+6- (18%); and MISR2-/ALK2+3+6+ (6.8%). No differences in overall survival (OS) were noted between combinations. The ALK6 receptor was least often expressed T1R and was associated with lower OS in early stage disease only (p =0.03). Most primary cell cultures expressed MISR2 (14/22 (63.6%)): 95% of these express ALK 2 and ALK3, whereas 54.5% expressed ALK6. MIS-dependent Smad phosphorylation was seen in the majority of cultures (75%). Treatment with MIS led to reduced cell viability at an average of 71% (range: 57-87%) in primary cultures. MIS signaling is dependent upon the presence of both MISR2 and specific T1R. In the majority of EOC, the T1R required for MIS-dependent signaling are present and such cells demonstrate appropriate response to MIS.


Assuntos
Receptores de Ativinas Tipo I/genética , Hormônio Antimülleriano/farmacologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Isoformas de Proteínas/genética , Receptores de Peptídeos/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Proteínas Smad/genética , Receptores de Ativinas Tipo I/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Epitelial do Ovário , Feminino , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Ovário/metabolismo , Ovário/patologia , Cultura Primária de Células , Isoformas de Proteínas/metabolismo , Receptores de Peptídeos/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Análise de Sobrevida , Análise Serial de Tecidos , Células Tumorais Cultivadas
5.
Biochim Biophys Acta ; 878(3): 310-9, 1986 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-3092869

RESUMO

Primary cultures of adult rat hepatocytes were used to compare the uptake and esterification of essential polyunsaturated fatty acids (18:2, 20:3 and 20:4 of the n-6 series) with those of palmitic and oleic acids. The uptake of unesterified fatty acids was linearly related to the free fatty acid/albumin molar ratio for 14 h and did not depend on the unbound free fatty acid level. Whatever the initial free fatty acid/albumin molar ratio, it dropped to 0.5 +/- 0.1 mM after 14 h, thus showing that hepatocytes have a high capacity for clearing free fatty acids from the medium at high free fatty acid/albumin molar ratios. The free fatty acid uptake become saturable when the free fatty acid and albumin concentrations were raised and the free fatty acid/albumin ratio remained constant. This strongly suggests that albumin-hepatocyte interaction mediates free fatty acid uptake. This uptake was identical whatever the fatty acid tested and did not depend on the relative amounts of fatty acids when they were added simultaneously. Triacylglycerol accumulation and synthesis, monitored by labelled fatty acids, were related to the free fatty acid/albumin molar ratio and exhibited no specificity for the series of fatty acids tested. Triacylglycerols were enriched in all the fatty acids tested by up to 60%, and fatty acid incorporation into diacylglycerols and triacylglycerols reflected the free fatty acid composition of the medium. By contrast, neither the level nor the synthesis of phospholipids varied with free fatty acid/albumin, but the rate of phospholipid turnover depended on the fatty acids tested. Accumulation of these acids was smaller in phospholipids than in triacylglycerols. When linoleic and arachidonic acids were added together, phospholipids (especially phosphatidylethanolamine and phosphatidylinositol) were more enriched in arachidonic acid than triacylglycerols. This might be due to the specificity for fatty acid of the enzymes involved in phospholipid metabolism.


Assuntos
Ácidos Graxos Essenciais/metabolismo , Fígado/metabolismo , Animais , Ácido Araquidônico , Ácidos Araquidônicos/metabolismo , Células Cultivadas , Esterificação , Ácidos Graxos não Esterificados/metabolismo , Ácido Linoleico , Ácidos Linoleicos/metabolismo , Masculino , Ácido Oleico , Ácidos Oleicos/metabolismo , Ácido Palmítico , Ácidos Palmíticos/metabolismo , Fosfolipídeos/metabolismo , Ratos , Ratos Endogâmicos , Albumina Sérica/metabolismo , Triglicerídeos/metabolismo
6.
Biochim Biophys Acta ; 727(2): 313-26, 1983 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-6838875

RESUMO

In order to study the effect of linoleyl enrichment of platelet membranes upon adenylate cyclase activity and membrane fluidity, manipulations of platelet phospholipids are carried out with phosphatidylcholine-loaded high-density lipoproteins (HDL) or phospholipid-exchange protein and phospholipid-cholesterol mixed vesicles. Incubation with HDL does not appear to be valuable for this purpose. On the other hand, phospholipid-exchange protein and mixed vesicles can be used successfully. Phospholipid-exchange protein stimulated 3-fold the spontaneous exchange of 2-linoleylphosphatidylcholine between the vesicles and the platelets. Linoleyl enrichment of platelets by dilinoleylphosphatidylcholine is about 25% and by 2-linoleylphosphatidylcholine is about 45-50%. The unsaturation index remains constant when the enrichment is performed using dilinoleylphosphatidylcholine but it increases with 2-linoleylphosphatidylcholine. Basal and prostaglandin E1-stimulated adenylate cyclase activities are not modified by dilinoleylphosphatidylcholine, while they increase significantly in the case of 2-linoleylphosphatidylcholine. There is no significant variation in diphenyl hexatriene fluorescence polarization parameters, either with dilinoleylphosphatidylcholine or with 2-linoleylphosphatidylcholine.


Assuntos
Adenilil Ciclases/sangue , Plaquetas/metabolismo , Membrana Celular/metabolismo , Lipoproteínas HDL/sangue , Lipossomos , Fluidez de Membrana , Fosfatidilcolinas/sangue , Humanos , Ácidos Linoleicos/sangue , Ácidos Linoleicos/síntese química
7.
Biochim Biophys Acta ; 833(1): 161-4, 1985 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-3917686

RESUMO

The synthesis of arachidonic acid has been investigated in fetal and pregnant rat liver microsomes in the course of the gestation. The delta 5-desaturase activity decreased 2-3 times in rat liver between the 19th and 22nd day of the pregnancy. During this period the delta 5-desaturate activity increased 3-fold in the fetal liver, exceeding the activity of the maternal liver. In contrast, the activity of the fetal delta 6-desaturase was in the same range as in pregnant rat liver and the liver of control animals and did not change between these two stages of the gestation. The elongation rate of linoleic acid in fetal liver was 2-3 times lower than in maternal liver but this increased during the pregnancy. The fatty acid activate rate was always higher than the activity of the desaturases. At the 19th day, the activity of the delta 5-desaturase was apparently the rate limiting step of arachidonic acid synthesis in fetal liver. We did not find any delta 5- and delta 6-desaturase activities or linoleic acid elongation in the placenta microsomes.


Assuntos
Ácidos Araquidônicos/biossíntese , Microssomos Hepáticos/metabolismo , Placenta/enzimologia , Animais , Ácido Araquidônico , Ácidos Graxos Dessaturases/metabolismo , Feminino , Idade Gestacional , Malonil Coenzima A/metabolismo , Microssomos Hepáticos/enzimologia , Gravidez , Ratos
8.
Biochim Biophys Acta ; 1006(1): 52-8, 1989 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-2804071

RESUMO

Primary cultures of rat hepatocytes were incubated in the presence of high-density lipoproteins (HDL) labelled with [1-14C]oleyl or [1-14C]linoleyl cholesteryl ester. Labelled HDL were prepared by selective delipidation with heptane, relipidation and sequential ultracentrifugations. Hepatocytes took up cholesteryl esters and cholesteryl ether their non-hydrolizable analog, at the same rate. The uptake increased with time, the cholesteryl ester/protein ratio and the amount of added HDL. It was not dependent on the nature of acyl chain or on the nature of the bond. The uptake did not depend on a specific interaction between HDL and cell membranes, since cholesteryl ester was taken up from HDL to the same extent as from albumin complexes. Linoleic and oleic acids released from cholesteryl esters taken up by hepatocytes were mainly reesterified into phosphatidylcholine and triacylglycerols. Linoleic acid was preferentially channelled into PC. A portion of these lipids were secreted by hepatocytes during a 24-h reincubation in a medium devoid of lipoprotein. Nearly the same amount of radioactivity was recovered in secreted phospholipids as in secreted triacylglycerols, in contrast with hepatocytes labelled with free fatty acids which secreted very little radioactivity as phospholipids. From these results and the high content in polyunsaturated fatty acids of cholesteryl esters, one can hypothesize that hepatic cholesteryl ester uptake may contribute to biliary phosphatidylcholine production, and therefore to polyunsaturated fatty acid sparing.


Assuntos
Ésteres do Colesterol/metabolismo , Ácidos Graxos/metabolismo , Lipoproteínas HDL/metabolismo , Fígado/metabolismo , Animais , Apolipoproteínas/análise , Células Cultivadas , Eletroforese em Gel de Poliacrilamida , Fígado/citologia , Ratos , Ratos Endogâmicos
9.
Biochim Biophys Acta ; 1087(2): 219-25, 1990 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-2223883

RESUMO

A partial rat apo E-beta-galactosidase fusion protein was produced in Escherichia coli Y1089 infected with recombinant lambda GT11 obtained by immunoscreening of a rat liver cDNA library with an anti-rat LDL antiserum. Partial cDNA overlapped the apo E mRNA sequence coding for apo E binding domain towards the LDL(B/E) receptor up to codon for Arg-139. Fusion protein specifically bound to human fibroblasts. The high-affinity component exhibited a Kd of 5 x 10(-8) M and 4.1 x 10(5) sites per cell. Fusion protein binding to fibroblasts was mediated by their apo E moiety and not by beta-galactosidase since: (1) specific binding of fusion protein was competed out by human LDL; (2) beta-galactosidase did not compete with fusion protein binding; and (3) human fibroblasts from a patient with familial hypercholesterolemia, deficient in LDL(B/E) receptor, bound fusion protein 10-times lower than control fibroblasts. It was demonstrated that partial fusion protein retained the functional activity of the native apo E. However, compared to full-length native or engineered apo E, fusion protein was able to bind fibroblasts without being complexed with phospholipids. Fusion proteins might be a useful tool for studying the functional efficiency of the LDL(B/E) receptor and for mapping residues and domains involved in the binding process.


Assuntos
Apolipoproteínas E/metabolismo , Escherichia coli/enzimologia , Receptores de LDL/metabolismo , Apolipoproteínas E/genética , Sequência de Bases , Células Cultivadas , Clonagem Molecular , Códon , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Expressão Gênica , Humanos , Hipercolesterolemia/metabolismo , Dados de Sequência Molecular , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Mapeamento por Restrição
10.
Biochim Biophys Acta ; 1086(3): 279-86, 1991 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-1742319

RESUMO

In primary culture of rat hepatocytes, simvastatin, a powerful HMGCoA reductase inhibitor, inhibited acetate incorporation into cellular and secreted cholesterol and cholesteryl-esters, without any significant effect on triacylglycerol synthesis and secretion. When applied to the culture for 24 h at 10(-7) M, a concentration shown to inhibit cholesterol synthesis by 61%, simvastatin increased apolipoprotein BH and BL synthesis and secretion and strongly decreased apolipoprotein AI synthesis and secretion whereas apolipoprotein AIV remained unaffected. The synthesis and secretion of apolipoprotein E was only slightly affected in contrast with other situations where cholesterol synthesis decreased. All of these modifications occurred at a post-transcriptional level, as the corresponding messenger RNAs of the apolipoproteins did not vary. These results suggest that either the drug itself or variations in cholesterol synthesis might be involved in apo B and apo AI synthesis and secretion.


Assuntos
Colesterol/metabolismo , Lipoproteínas/biossíntese , Lipoproteínas/metabolismo , Fígado/metabolismo , Lovastatina/análogos & derivados , Animais , Animais Recém-Nascidos , Células Cultivadas , Ésteres do Colesterol/metabolismo , Ácidos Graxos/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases , Fígado/citologia , Fígado/efeitos dos fármacos , Lovastatina/farmacologia , Masculino , Metionina/metabolismo , Ratos , Ratos Endogâmicos , Sinvastatina , Triglicerídeos/metabolismo
11.
J Bone Miner Res ; 16(11): 2152-60, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11697813

RESUMO

Fermentable carbohydrates have been shown to be nondigestible by human enzymes in the small intestine but are fermented extensively in the large bowel to short-chain fatty acids (SCFAs), which can increase mineral absorption. It has been shown that feeding such carbohydrates including short-chain fructo-oligosaccharides (sc-FOSs) increases intestinal magnesium (Mg) absorption in animals, but their beneficial impact on Mg absorption in humans still remains to be established. Therefore, this work aimed to investigate the effect of moderate daily doses of sc-FOSs (10 g/day) on the intestinal absorption and status of Mg in postmenopausal women without hormone replacement therapy (HRT). Eleven healthy postmenopausal women aged 59 +/- 6 years (mean +/- SD) received for 5 weeks sc-FOS or sucrose (placebo) treatments according to a randomized, double-blind, crossover design separated by a washout period of at least 3 weeks. Subjects ingested 87.5 mg of stable isotope 25Mg together with a fecal marker. Subsequently, feces were collected for 5-7 days. An inductively coupled plasma mass spectrometer (ICP/MS) was used for 25Mg stable isotope measurements in feces, urine, and blood. Mg levels were assessed also at the beginning and at the end of each treatment in plasma, erythrocytes, and urine. These measurements allowed for the determination of net intestinal Mg absorption and Mg status. The results show that the addition of 10 g sc-FOS to the diet increased Mg absorption by 12.3%, from 30.2 +/- 5.0% (placebo treatment) to 33.9 +/- 7.2% (sc-FOS treatment; mean +/- SD; p < 0.02). This increase in intestinal Mg absorption was accompanied by an increase in plasma 25Mg level and led to a higher urinary 25Mg excretion. This is the first time that such an effect is shown in humans. The overall conclusion of this work is that the ingestion of moderate doses of sc-FOS did improve intestinal Mg absorption and status in postmenopausal women. Because of the important role of Mg in many cellular functions, such Mg absorption improvement may be particularly interesting when the dietary intake of Mg is limited.


Assuntos
Carboidratos da Dieta/administração & dosagem , Absorção Intestinal/efeitos dos fármacos , Magnésio/farmacocinética , Oligossacarídeos/administração & dosagem , Idoso , Animais , Disponibilidade Biológica , Estudos Cross-Over , Método Duplo-Cego , Fezes/química , Feminino , Humanos , Isótopos , Magnésio/sangue , Magnésio/urina , Pessoa de Meia-Idade
12.
FEBS Lett ; 219(1): 113-8, 1987 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-3109950

RESUMO

In bovine adrenocortical cells, the fatty acyl chains of the phospholipids have been identified in the membranes of the different cell compartments: plasma membranes, Golgi complex and coated vesicle membranes. An increase in the total number of unsaturation in the fatty acid is demonstrated in the coated vesicle membranes as compared with the plasma and Golgi membranes. Furthermore, it appears that phosphatidylcholine and phosphatidylethanolamine are both enriched in polyunsaturated fatty acyl chains, namely arachidonic and adrenic acids in both types of coated vesicles. Only two of the fatty acids are characteristic of Golgi complex and small coated vesicles, 22:5 (n-6) in PC and 22:6 (n-3) in PE, suggesting that the SCV could originate from the Golgi stacks. A high value of the ratio 22:5 (n-3)/22:6 (n-3) is observed which is, as far as we know, characteristic of adrenal cells.


Assuntos
Córtex Suprarrenal/análise , Ácidos Graxos Insaturados/isolamento & purificação , Lipídeos de Membrana/isolamento & purificação , Fosfolipídeos/isolamento & purificação , Animais , Bovinos , Membrana Celular/análise , Invaginações Revestidas da Membrana Celular/análise , Complexo de Golgi/análise
13.
FEBS Lett ; 222(1): 11-6, 1987 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-2443388

RESUMO

Polyclonal antiserum was prepared against phospholipase A2 from Naja naja and used to prepare a purified antibody. It cross-reacted with the antigen, and with intracellular mammalian PLA2. This antibody was immunoreactive and inhibited the PLA2 activity of Naja naja and of guinea pig alveolar macrophages or rat lymphocytes. By immunoblotting, this antiserum revealed one band of PLA2 from Naja naja (14 kDa) and 3 bands for guinea pig alveolar macrophages and rat lymphocytes (30, 45 kDa and a minor band of 14 kDa). These results show an antigenic relatedness between an extracellular PLA2 and membrane-bound PLA2 from two different mammalian species and cell types.


Assuntos
Venenos Elapídicos/imunologia , Epitopos/análise , Linfócitos/enzimologia , Macrófagos/enzimologia , Fosfolipases A/imunologia , Fosfolipases/imunologia , Animais , Complexo Antígeno-Anticorpo , Cobaias , Soros Imunes , Fosfolipases A2 , Ratos , Especificidade da Espécie
14.
J Am Soc Mass Spectrom ; 12(10): 1077-84, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11605968

RESUMO

Potassium bromate salt clusters, [KBrO3]nKx(x+), formed by electrospray ionization were studied as a function of solution properties. Clusters with up to 4 positive charges were observed. Their abundance, charge state and distribution were shown to vary with the organic solvent in solution. The effects of 7 solvents, including methanol, ethanol, isopropanol, acetonitrile, acetone, pyridine, and 1,4-dioxane, were thoroughly investigated. Solvents with a low dielectric constant and a high viscosity seem to favor clustering in solution but do not systematically allow high charge state ion formation. On the other hand, cluster charge reduction during desolvation was not correlated with solvent cation affinity over the range of solvents examined. However, ion distribution in mass spectra could be rationalized as a combination of these two competing phenomena. Charge state increases with the cluster size but may be reduced during ion desolvation when high cation affinity solvent molecules are actually involved in the ion solvation shell. This assumption could be envisaged in either Iribarne or Dole mechanisms of ion release in the gas phase. However, intensity profiles of multiply charged clusters could only be understood in terms of the ion evaporation mechanism.

15.
Leuk Res ; 22(1): 77-80, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9585083

RESUMO

Thirty-three patients with acute lymphoblastic leukemia (ALL) from India were studied for the presence of BCR-ABL chimeric transcripts, by a seminested cDNA-PCR. We report the presence of BCR-ABL chimeric transcripts in 4/17 (24%) children (under 15 years) and 3/16 (19%) adults (15-50 years). This is in sharp contrast to the published literature from the West where the presence of BCR-ABL has been reported in only 2-5% children and 35% adults. Whether the presence of BCR-ABL fusion mRNA, which is generally an attribute of ALL in adults and of poorer prognosis, may contribute to chemo-incurability in young Indian patients, remains to be seen, as a larger number of patients are studied for treatment outcome and survival on uniform therapy protocols.


Assuntos
Proteínas de Fusão bcr-abl/genética , Genes abl , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Adulto , Criança , Pré-Escolar , Proteínas de Fusão bcr-abl/análise , Regulação Neoplásica da Expressão Gênica , Humanos , Índia/epidemiologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Transcrição Gênica
16.
Clin Chim Acta ; 310(2): 123-30, 2001 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-11498077

RESUMO

BACKGROUND: Pentane in exhaled gas is often used as an index of lipoperoxidation, but today, there is no standardization for its measurement. In this study, with our technical experience, we determined basal production of pentane in healthy subjects, and we evaluated variability of pentane flow 1 month later. METHODS: 18 subjects inhaled hydrocarbon-free air (HCFA) in order to realize a lung washout. Ambient air and three samples (at T0, T10, T30 min) of expired gas were concentrated using a "trap-and-purge" procedure. For the analysis of pentane, an Al(2)O(3)/KCl plot column contained in a gas chromatograph equipped with a flame ionization detector was used. RESULTS: After 10 min of washout, mean (+/-SD) exhalation rate of pentane was 1+/-0.6 pmol min(-1) kg(-1). After 30 min of washout, mean (+/-SD) exhalation rate of pentane was 0.7+/-0.5 pmol min(-1) kg(-1). No significant difference in pentane flow was shown 1 month later for eight subjects who repeated the protocol. CONCLUSION: With our results and data of the literature, exhalation rates of pentane from healthy adults appear to range between 0.3 and 2 pmol min(-1) kg(-1). The variability of pentane flow 1 month later seems not very important.


Assuntos
Peroxidação de Lipídeos , Pentanos/metabolismo , Respiração , Adulto , Idoso , Cromatografia Gasosa , Feminino , Ionização de Chama , Humanos , Masculino , Pessoa de Meia-Idade , Pentanos/análise , Valores de Referência
17.
J Chromatogr A ; 804(1-2): 105-11, 1998 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-9615400

RESUMO

A sensitive method for analyzing chlorite, chlorate, bromate and iodate in water by ion chromatography (IC) coupled with ionspray tandem mass spectrometry (IS-MS-MS) has been developed. Prior to analysis, samples were subjected to off-line sample clean-up with Ba, Ag and H-form resins to remove sulfate, chloride and hydrogencarbonate, respectively. Oxyhalides in the purified samples were concentrated and separated on a short, high-performance anion-exchange column. An eluent consisting of ammonium nitrate in methanol-water (9:1, v/v) was found to be suitable for separating the analytes, while providing enhanced detector sensitivity. The coupling of IC with IS-MS-MS allows for the identification of the four oxyhalides mentioned above in a single run with very high specificity and sensitivity.


Assuntos
Halogênios/análise , Espectrometria de Massas/métodos , Água/química , Ingestão de Líquidos , Halogênios/química , Metanol/química , Sensibilidade e Especificidade
18.
Steroids ; 67(13-14): 1057-64, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12441191

RESUMO

Metabolism of dehydroepiandrosterone (DHEA), its sulfate (DHEAS), and androstene-3,17-dione (delta(4)) was performed at their physiological plasma concentrations in MCF-7 cell cultures (1 microM, 10 and 2 nM, respectively). Final metabolic products of these steroids were separated by HPLC-radioactive flow detection and identified by LC/MS or MS/MS. Typical and specific mass fragmentation spectra identified the presence of estrone (E(1)), 17beta-estradiol (E(2)), delta(4), DHEA, 5-androstene-3beta,17beta-diol (delta(5)), and testosterone as principal DHEAS metabolites. Other steroids, such as androstenedione, androsterone, and DHEA fatty acid esters at very low concentrations (from pM to nM), were also obtained after steroid incubation. This highly specific method allowed us to conclude whether a metabolite and enzymatic activity of interest were present in MCF-7 cells or not. We also showed that DHEAS at its physiological plasma concentration may be converted into estrogens and estrogen-like compounds in breast cancer cells. The estrogenic action of DHEAS on breast cancer cells was also measured by bioluminescence in a stably transfected human breast cancer MCF-7 cell line with a reporter gene that allowed expression of the firefly luciferase enzyme under the control of an estrogen regulatory element.


Assuntos
Sulfato de Desidroepiandrosterona/metabolismo , Estrogênios/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Divisão Celular , Desidroepiandrosterona/metabolismo , Sulfato de Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter/genética , Espectrometria de Massas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
19.
Biomed Pharmacother ; 55(3): 163-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11325214

RESUMO

In order to estimate cell damage caused by free radicals during oxygenotherapy, we investigated the time course of two markers of lipoperoxidation: pentane in breath and malondialdehyde (MDA) in blood during brief normobaric hyperoxia. Nine healthy subjects inhaled hydrocarbon-free air (HCFA) for 30 minutes, hydrocarbon-free 100% O2 (HCFO2) for 125 minutes and then HCFA for 70 minutes. After 15 minutes of washout with HCFA, ambient pentane was eliminated. After HCFO2, at T175 versus T30 (i.e., 145 min from the start of 100% HCFO2), pentane production increased (P< 0.05). MDA rose significantly at T155 min (i.e., 125 min from the start of HCFO2), versus T30 (P< 0.01). These results suggest that acute hyperoxia causes a moderate increase in lipid peroxidation in healthy subjects. The increase of pentane and MDA confirms that acute hyperoxia induces lipid peroxidation in healthy subjects.


Assuntos
Hiperóxia/metabolismo , Malondialdeído/sangue , Oxigenoterapia/efeitos adversos , Pentanos/metabolismo , Idoso , Biomarcadores , Testes Respiratórios , Feminino , Humanos , Hidrocarbonetos/análise , Hiperóxia/sangue , Masculino , Pessoa de Meia-Idade
20.
JPEN J Parenter Enteral Nutr ; 10(2): 216-9, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3083136

RESUMO

In order to prevent essential fatty acid (EFA) deficiency induced by fat-free total parenteral nutrition (TPN), 10 infants on TPN were rubbed three times daily for 20 days using oenethera oil (80% EFA). Total EFA amount provided cutaneously was 1900 mg/kg/d. Plasma and red blood cells phospholipids were determined on days 1 and 20 in these 10 treated and six untreated infants on TPN and compared with those of normal control infants. On day 1, plasma nonessential FA including 20:3 n-9(p less than 0.01) were increased in both TPN groups while 18:2 n-6 and 18:3 n-3 (p less than 0.001 and p less than 0.01) were decreased. On the 20th day, EFA deficiency had worsened with a decrease in plasma level of 20:4 n-6 (p less than 0.02) and a higher than normal triene/tetraene ratio : 3.4 +/- 1.1 and 2.3 +/- 0.6 vs 0.1 +/- 0.1 (p less than 0.02). As for red blood cells phospholipids, 16:0 was increased and 18:2 n-6 and 20:3 n-6 were decreased (p less than 0.05) on day 1. On day 20, these FA were more abnormal while 20:3 n-9 became significantly increased (p less than 0.05). No difference was observed between the TPN groups at any time. These results show that cutaneous application of large amounts of EFA-rich oil is unable to prevent or cure TPN induced EFA deficiency.


Assuntos
Ácidos Graxos Essenciais/sangue , Nutrição Parenteral Total/efeitos adversos , Absorção , Administração Tópica , Eritrócitos/metabolismo , Ácidos Graxos Essenciais/administração & dosagem , Ácidos Graxos Essenciais/deficiência , Humanos , Lactente , Pele/metabolismo , Fatores de Tempo
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