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1.
Radiat Res ; 198(1): 81-88, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35405740

RESUMO

Previous epidemiological studies have demonstrated elevated susceptibility to ionizing radiation in some families, thus suggesting the presence of genetic components that conferred increased rate of radiation-associated meningioma (RAM). In this study, we exome-sequenced and investigated the segregation pattern of rare deleterious variants in 11 RAM pedigrees. In addition, we performed a rare-variant association analysis in 92 unrelated familial cases of RAM that were ancestry-matched with 88 meningioma-free controls. In the pedigree analysis, we found that each family carried mostly a unique set of rare deleterious variants. A follow-up pathway analysis of the union of the genes that segregated within each of the 11 pedigrees identified a single statistically significant (q value = 7.90E-04) "ECM receptor interaction" set. In the case-control association analysis, we observed no statistically significant variants or genes after multiple testing correction; however, examination of ontological categories of the genes that associated with RAM at nominal P values <0.01 identified biologically relevant pathways such as DNA repair, cell cycle and apoptosis. These results suggest that it is unlikely that a small number of highly penetrant genes are involved in the pathogenesis of RAM. Substantially larger studies are needed to identify genetic risk variants and genes in RAM.


Assuntos
Exoma , Predisposição Genética para Doença , Estudos de Casos e Controles , Humanos , Linhagem , Radiação Ionizante
2.
Oncogene ; 36(22): 3168-3177, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28068329

RESUMO

Neurofibromatosis type 1 (NF1) is a common tumor-predisposition disorder due to germline mutations in the tumor suppressor gene NF1. A virtually pathognomonic finding of NF1 is the plexiform neurofibroma (PN), a benign, likely congenital tumor that arises from bi-allelic inactivation of NF1. PN can undergo transformation to a malignant peripheral nerve sheath tumor, an aggressive soft-tissue sarcoma. To better understand the non-NF1 genetic contributions to PN pathogenesis, we performed whole-exome sequencing, RNASeq profiling and genome-wide copy-number determination for 23 low-passage Schwann cell cultures established from surgical PN material with matching germline DNA. All resected tumors were derived from routine debulking surgeries. None of the tumors were considered at risk for malignant transformation at the time; for example, there was no pain or rapid growth. Deep (~500X) NF1 exon sequencing was also conducted on tumor DNA. Non-NF1 somatic mutation verification was performed using the Ampliseq/IonTorrent platform. We identified 100% of the germline NF1 mutations and found somatic NF1 inactivation in 74% of the PN. One individual with three PNs had different NF1 somatic mutations in each tumor. The median number of somatic mutations per sample, including NF1, was one (range 0-8). NF1 was the only gene that was recurrently somatically inactivated in multiple tumors. Gene Set Enrichment Analysis of transcriptome-wide tumor RNA sequencing identified five significant (FDR<0.01) and seven trending (0.01⩽FDR<0.02) gene sets related to DNA replication, telomere maintenance and elongation, cell cycle progression, signal transduction and cell proliferation. We found no recurrent non-NF1 locus copy-number variation in PN. This is the first multi-sample whole-exome and whole-transcriptome sequencing study of NF1-associated PN. Taken together with concurrent copy-number data, our comprehensive genetic analysis reveals the primacy of NF1 loss as the driver of PN tumorigenesis.


Assuntos
Neurofibroma Plexiforme/patologia , Neurofibromatose 1/patologia , Neurofibromina 1/deficiência , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Replicação do DNA , Dosagem de Genes , Genes Supressores de Tumor , Mutação em Linhagem Germinativa , Humanos , Neurofibroma Plexiforme/genética , Neurofibroma Plexiforme/metabolismo , Neurofibromatose 1/genética , Neurofibromatose 1/metabolismo , Neurofibromina 1/genética , Transcriptoma
3.
Br J Pharmacol ; 173(3): 484-96, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26493539

RESUMO

BACKGROUND AND PURPOSE: In the phase III clinical trial, RELAX-AHF, serelaxin caused rapid and long-lasting haemodynamic changes. However, the cellular mechanisms involved are unclear in humans. EXPERIMENTAL APPROACH: This study examined the effects of serelaxin in co-cultures of human primary endothelial cells (ECs) and smooth muscle cells (SMCs) on cAMP and cGMP signalling. KEY RESULTS: Stimulation of HUVECs or human coronary artery endothelial cells (HCAECs) with serelaxin, concentration-dependently increased cGMP accumulation in co-cultured SMCs to a greater extent than in monocultures of either cell type. This was not observed in human umbilical artery endothelial cells (HUAECs) that do not express the relaxin receptor, RXFP1. Treatment of ECs with l-N(G) -nitro arginine (NOARG; 30 µM, 30 min) inhibited serelaxin-mediated (30 nM) cGMP accumulation in HUVECs, HCAECs and co-cultured SMCs. In HCAECs, but not HUVECs, pre-incubation with indomethacin (30 µM, 30 min) also inhibited cGMP accumulation in SMCs. Pre-incubation of SMCs with the guanylate cyclase inhibitor ODQ (1 µM, 30 min) had no effect on serelaxin-mediated (30 nM) cGMP accumulation in HUVECs and HCAECs but inhibited cGMP accumulation in SMCs. Serelaxin stimulation of HCAECs, but not HUVECs, increased cAMP accumulation concentration-dependently in SMCs. Pre-incubation of HCAECs with indomethacin, but not l-NOARG, abolished cAMP accumulation in co-cultured SMCs, suggesting involvement of prostanoids. CONCLUSIONS AND IMPLICATIONS: In co-cultures, treatment of ECs with serelaxin caused marked cGMP accumulation in SMCs and with HCAEC also cAMP accumulation. Responses involved EC-derived NO and with HCAEC prostanoid production. Thus, serelaxin differentially modulates vascular tone in different vascular beds.


Assuntos
Vasos Coronários/citologia , Células Endoteliais/metabolismo , Miócitos de Músculo Liso/metabolismo , Relaxina/farmacologia , Artérias Umbilicais/citologia , Veias Umbilicais/citologia , Técnicas de Cocultura , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Humanos , Indometacina/farmacologia , Nitroarginina/farmacologia , Oxidiazóis/farmacologia , Quinoxalinas/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/metabolismo , Proteínas Recombinantes/farmacologia , Transdução de Sinais
4.
Br J Pharmacol ; 172(4): 1005-19, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25297987

RESUMO

BACKGROUND AND PURPOSE: In a recently conducted phase III clinical trial, RELAX-AHF, serelaxin infusion over 48 h improved short- and long-term clinical outcomes in patients with acute heart failure. In this study we used human primary cells from the umbilical vasculature to better understand the signalling mechanisms activated by serelaxin. EXPERIMENTAL APPROACH: We examined the acute effects of serelaxin on signal transduction mechanisms in primary human umbilical vascular cells and its chronic actions on markers of cardiovascular function and disease. KEY RESULTS: The RXFP1 receptor, the cognate serelaxin receptor, was expressed at the cell surface in HUVECs and human umbilical vein smooth muscle cells (HUVSMCs), human umbilical artery smooth muscle cells (HUASMCs) and human cardiac fibroblasts (HCFs), but not human umbilical artery endothelial cells. In HUVECs and HUVSMCs, serelaxin increased cAMP, cGMP accumulation and pERK1/2, and the concentration-response curves (CRCs) were bell-shaped. Similar bell-shaped CRCs for cGMP and pERK1/2 were observed in HCFs, whereas in HUASMCs, serelaxin increased cAMP, cGMP and pERK1/2 with sigmoidal CRCs. Gαi/o and lipid raft disruption, but not Gαs inhibition, altered the serelaxin CRC for cAMP and cGMP accumulation in HUVSMC but not HUASMC. Longer term serelaxin exposure increased the expression of neuronal NOS, VEGF, ETß receptors and MMPs (gelatinases) in RXFP1 receptor-expressing cells. CONCLUSIONS AND IMPLICATIONS: Serelaxin caused acute and chronic changes in human umbilical vascular cells that were cell background dependent. Bell-shaped CRCs that were observed only in venous cells and fibroblasts involved Gαi/o located within membrane lipid rafts.


Assuntos
Células Endoteliais/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Proteínas de Ligação ao GTP/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Relaxina/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Fibroblastos/metabolismo , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Miócitos de Músculo Liso/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Receptor de Endotelina B/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/metabolismo , Proteínas Recombinantes/farmacologia , Transdução de Sinais , Artérias Umbilicais/citologia , Veias Umbilicais/citologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
5.
Andrology ; 3(1): 47-58, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25303766

RESUMO

This Review summarizes the cumulative results of the National Cancer Institute Clinical Genetics Branch Multidisciplinary Etiologic Study of Familial Testicular Germ Cell Tumors (FTGCT). Initiated 12 years ago, this protocol enrolled 724 subjects from 147 unrelated families with either ≥2 affected men (n = 90) with TGCT or a proband with bilateral TGCT and a negative family history for this cancer (n = 57). Data were collected directly from 162 subjects evaluated at the NIH Clinical Center, and 562 subjects provided information from their home communities (Field Cohort). The primary study aims included (i) ascertaining, enrolling eligible FTGCT kindred, (ii) characterizing the clinical phenotype of multiple-case families, (iii) identifying the underlying genetic mechanism for TGCT susceptibility in families, (iv) evaluating counseling, psychosocial, and behavioral issues resulting from membership in an FTGCT family, and (v) creating an annotated biospecimen repository to permit subsequent translational research studies. Noteworthy findings include (i) documenting the epidemiologic similarities between familial and sporadic TGCT, (ii) demonstrating significantly younger age-at-diagnosis for familial vs. sporadic TGCT, (iii) absence of a dysmorphic phenotype in affected family members, (iv) shifting the focus of gene discovery from a search for rare, highly penetrant susceptibility variants to the hypothesis that multiple, more common, lower penetrance genes underlie TGCT genetic risk, (v) implicating testicular microlithiasis in FTGCT risk, and (vi) observing that aberrant methylation may contribute to FTGCT risk. A clinically based, biospecimen-intensive, multidisciplinary research strategy has provided novel, valuable insights into the etiology of FTGCT, and created a research resource which will support FTGCT clinical and laboratory studies for years to come.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Testiculares/genética , Bancos de Espécimes Biológicos , Aconselhamento Genético , Predisposição Genética para Doença , Testes Genéticos , Hereditariedade , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/terapia , Linhagem , Fenótipo , Medicina de Precisão , Prognóstico , Projetos de Pesquisa , Medição de Risco , Fatores de Risco , Neoplasias Testiculares/patologia , Neoplasias Testiculares/terapia
6.
Pharmazie ; 61(10): 835-44, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17069422

RESUMO

AP5346 is a low molecular weight polymer-conjugated platinum antineoplastic agent. The lyophilized drug product has completed a phase I clinical trial. In order to guarantee a constant quality of AP5346 pharmaceutical products, quality control and analysis of the drug substance and final product were performed. The identity of AP5346 was confirmed using 1H NMR, 195Pt NMR and IR spectroscopy. Furthermore, the free platinum content, platinum release characteristics, molecular size and size distribution were established. With the selected analytical techniques, AP5346 could be distinguished very well from its polymeric analogues, such as AP5280 and AP5279. Stability experiments revealed that AP5346 final product is stable for 12 months at 5 degrees C, in the dark. For administration to patients, AP5346 final product is reconstituted with 5% w/v dextrose and diluted in infusion containers. To investigate the influence of container materials, the stability of AP5346 after reconstitution and dilution in infusion containers was determined. The infusion containers investigated were composed of glass, polyvinyl chloride (PVC, intraflex) and low density polyethylene (LD-PE, Ecoflac). AP5346 was shown to be stable after reconstitution and dilution with 5% w/v dextrose in these infusion containers for at least 96 h at 2-8 degrees C in the dark and at room temperature with ambient light conditions.


Assuntos
Antineoplásicos/química , Compostos Organoplatínicos/química , Antineoplásicos/administração & dosagem , Varredura Diferencial de Calorimetria , Química Farmacêutica , Cromatografia em Gel , Reagentes de Ligações Cruzadas/química , DNA/química , Composição de Medicamentos , Incompatibilidade de Medicamentos , Liofilização , Espectroscopia de Ressonância Magnética , Compostos Organoplatínicos/administração & dosagem , Soluções Farmacêuticas , Platina/análise , Controle de Qualidade , Espectrofotometria Atômica , Espectrofotometria Infravermelho , Esterilização
7.
J Clin Endocrinol Metab ; 91(10): 4112-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16868051

RESUMO

CONTEXT: Little is known about genes that contribute to polycystic ovary syndrome (PCOS). We previously found linkage and association of PCOS with the dinucleotide marker D19S884 in two independent sets of families; allele 8 of D19S884 confers increased risk. OBJECTIVE/DESIGN: The objectives of the study were: 1) use the transmission/disequilibrium test (TDT) to assess linkage and association between PCOS and D19S884 (and nearby markers) in a third set of families; and 2) test D19S884 and surrounding DNA sequence for in vitro regulatory activity in lymphoblastoid cell lines (LCLs) and granulosa cells. SETTING/SUBJECTS: We studied 98 new families with a PCOS proband, father, mother, and other available offspring. We analyzed data from these families separately and in combination with data obtained previously. INTERVENTIONS: Interventions were venipuncture. MAIN OUTCOME MEASURES: Measures were transmission frequencies and in vitro functional studies. RESULTS: The first result we found was that in the 98 new families, the TDT was significant for allele 8 of D19S884 (P = 0.043). In the total collection of 465 families, the TDT evidence is very strong (nominal P < 7 x 10(-5)). Results for all other genetic markers near D19S884 were nonsignificant after correction for multiple testing. The second result was that an approximately 800-bp fragment containing various alleles of D19S884 showed modest but reproducible promoter activity in LCLs. However, no allelic differences were detected. No activity of this fragment was detected in granulosa cells. CONCLUSIONS: This is the second independent confirmation of linkage and association of D19S884 with PCOS. We found in addition that some sequence in the region of D19S884 confers in vitro promoter activity in LCLs.


Assuntos
Mapeamento Cromossômico , Cromossomos Humanos Par 19 , Predisposição Genética para Doença , Síndrome do Ovário Policístico/genética , Feminino , Genótipo , Humanos , Desequilíbrio de Ligação , Regiões Promotoras Genéticas , Sequências Repetitivas de Ácido Nucleico
8.
Br J Sports Med ; 38(4): 457-60, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15273185

RESUMO

OBJECTIVES: To investigate if ligamentous laxity increases seasonal incidence of injury in male first division club rugby players, and to determine if strength protects against injury in hypermobile and tight players. METHODS: Fifty one male first division club rugby players were examined for ligamentous laxity using the Beighton-Horan assessment and graded with an overall laxity score ranging from 0 (tight) to 9 (hyperlax). Each participant was classified into a group determined by their laxity score: tight (0-3), hypermobile (4-6), or excessively hypermobile (7-9). The incidence of joint injuries was recorded prospectively throughout the rugby season and correlated with laxity score. Differences between the groups were analysed. RESULTS: The overall prevalence of generalised joint hypermobility was 24% (12/51). The incidence of injuries was significantly higher in hypermobile (116.7 per 1000 hours) than tight (43.6 per 1000 hours) players (p = 0.034). There were no significant differences in peak strength between the hypermobile and tight groups. CONCLUSIONS: The laxity of the players may explain the differences in injury rates between these groups. Peak strength does not protect the hypermobile joint against injury. It appears that hypermobility may cause an increase in the injury rate of male first division club rugby players.


Assuntos
Futebol Americano/lesões , Instabilidade Articular/complicações , Adulto , Humanos , Instabilidade Articular/fisiopatologia , Ligamentos Articulares , Masculino , Músculo Esquelético/fisiologia
9.
Eur J Cancer ; 40(2): 291-7, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14728945

RESUMO

AP5280 is a novel N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-bound platinum (Pt) therapeutic designed to increase the therapeutic index relative to conventional, small-molecule platinum agents. The platinum-polymer construct accumulates in solid tumours on the basis of increased capillary permeability. The bound platinum moiety is present as an N,O-Pt chelate at the distal end of a tetrapeptide linker, glycine-phenylalanine-leucine-glycine, and the weight-average molecular weight (Mw) of the construct is 22 kDa. The antitumour activity and toxicity of AP5280 were assessed in the syngeneic murine B16F10 and Lewis lung tumour models, and in the human ovarian carcinoma 2008 and head and neck squamous carcinoma UMSCC10b xenograft models. The maximum tolerated dose (MTD) of AP5280 was 6-fold greater than that of carboplatin (CBDCA) in vivo. AP5280 was active in all four tumour models, and it displayed a higher therapeutic index than CBDCA in each of these tumour models. The antitumour effect of AP5280 given at 16% of its MTD was equivalent to that produced by a MTD of CBDCA. Thus, consistent with the design goal for this drug, and despite being less potent than CBDCA, AP5280 produced less systemic toxicity relative to its antitumour activity and thus has a greater therapeutic index. On the basis of the improved therapeutic index evidenced in these models, AP5280 has been advanced into clinical trials.


Assuntos
Acrilamidas/uso terapêutico , Antineoplásicos/uso terapêutico , Carboplatina/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Melanoma/tratamento farmacológico , Compostos Organoplatínicos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Acrilamidas/administração & dosagem , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sinergismo Farmacológico , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Concentração Inibidora 50 , Melanoma/patologia , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Neoplasias Ovarianas/patologia , Transplante Heterólogo , Ensaio Tumoral de Célula-Tronco
10.
Drug Dev Ind Pharm ; 29(9): 981-95, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14606662

RESUMO

AP 5280 is a novel polymer-conjugated platinum anticancer agent showing promising in vitro and in vivo activity against solid tumors. The aim of this study was to develop a parenteral pharmaceutical dosage form for phase I clinical trials. AP 5280 drug substance was characterized by using a wide range of analytical techniques and showed excellent solubility in water. However, as aqueous solutions of AP 5280 proved to be labile upon sterilization by moist heat, it was decided to develop a lyophilized dosage form. Initially, glass vials were used as primary packaging, but this led to a high breakage rate, which could be completely prevented by the use of CZ resin vials. Stability studies to date show that the lyophilized product in glass vials is stable for at least 12 months when stored at 2-8 degrees C in the dark and the lyophilized product in CZ resin vials is stable for at least 6 months under these conditions. Photostability testing revealed photolability of AP 5280 drug substance and lyophilized product in both types of primary container, necessitating storage in the dark. The first clinical experiences indicate that the proposed formulation is fully applicable for use in the clinical setting.


Assuntos
Acrilamidas/química , Antineoplásicos/química , Drogas em Investigação/química , Compostos Organoplatínicos/química , Tecnologia Farmacêutica/métodos , Acrilamidas/análise , Antineoplásicos/análise , Química Farmacêutica , Drogas em Investigação/análise , Liofilização/métodos , Infusões Parenterais , Compostos Organoplatínicos/análise , Compostos de Platina/análise , Compostos de Platina/química
11.
Anticancer Drugs ; 13(9): 915-24, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12394254

RESUMO

AP 5280 is a novel polymer-conjugated platinum anticancer agent currently undergoing phase I clinical trials. It is pharmaceutically formulated as a lyophilized product containing 200 mg platinum per dosage unit. The aim of this study was to determine the reconstitution and dilution fluid of choice, and to investigate the stability and compatibility of AP 5280 in solution under different storage conditions and with several container materials. Furthermore, the hemolytic potential of AP 5280 infusion solution was investigated. AP 5280 slowly released small platinum species in all solutions, although this release was enhanced in normal saline. Accordingly, 5% dextrose in water (D W) was selected for reconstitution and dilution of AP 5280. Container material [glass or polyvinylchloride (PVC)] did not influence the stability of AP 5280 in solution. Storage at refrigerated temperature (2-8 degrees C) marginally decreased the release rate of liberated platinum. The infusion solutions are compatible with the PVC infusion system and do not cause hemolysis. In conclusion, AP 5280 lyophilized product should be reconstituted and diluted to infusion concentration with D W, and administered within 8 h after preparation to ensure that less than 1.0% of the total platinum concentration is present as liberated platinum.


Assuntos
Acrilamidas/química , Antineoplásicos/química , Drogas em Investigação/química , Hemólise/efeitos dos fármacos , Compostos Organoplatínicos/química , Platina/análise , Cromatografia Líquida de Alta Pressão , Preparações de Ação Retardada/química , Dietilexilftalato/análise , Embalagem de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Humanos , Técnicas In Vitro , Bombas de Infusão , Espectroscopia de Ressonância Magnética , Modelos Biológicos , Polímeros/química , Soluções
12.
Anal Bioanal Chem ; 373(4-5): 233-6, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12110973

RESUMO

AP5280 is an N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer to which are linked tetrapeptide side chains containing bioactive platinum complexes at their C-terminal sides. We have developed and validated a rapid and sensitive analytical assay for the determination of total platinum concentrations in plasma, and free platinum of an AP5280 origin in plasma ultrafiltrate (PUF), of subjects dosed with AP5280. The total platinum levels were determined by use of graphite-furnace atomic-absorption spectrometry (GF-AAS) with Zeeman correction after appropriate dilution of the plasma sample with plasma-hydrochloric acid 0.2 mol L(-1) (1:5) as diluent. The limit of quantitation of this assay is 0.25 micromol L(-1) platinum in plasma. Linear calibration curves were obtained over the concentration range 0.25-5.0 micromol L(-1). Accuracy was between 87.7% and 104.2% and precision was 15.3% at the lowest concentration and less than 14% for all other levels tested. Accuracy and precision were thus in accordance with generally accepted criteria for analytical methods. Analysis of samples obtained from patients receiving AP5280 demonstrated the applicability of the described assay. Analysis of free platinum in PUF was performed by use of a previously validated and reported assay from our institute in which the same instrumental method is used.


Assuntos
Acrilamidas/administração & dosagem , Compostos Organoplatínicos/administração & dosagem , Platina/sangue , Acrilamidas/farmacocinética , Calibragem , Sistemas de Liberação de Medicamentos/normas , Hemofiltração , Humanos , Compostos Organoplatínicos/farmacocinética , Platina/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Atômica
13.
Biol Reprod ; 62(1): 200-5, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10611086

RESUMO

We have developed culture methods for human luteinizing granulosa cells (GLC) that support the timely and dynamic secretion of estrogen (estradiol-17beta; E(2)), progesterone (P(4)), and relaxin (Rlx) in patterns that mimic serum hormone concentrations during the luteal phase of the menstrual cycle. Additional hCG, to simulate rescue of the corpus luteum, prevented the normal decline in GLC hormone production. To test the importance of the P(4) receptor in P(4) production, GLC were treated in vitro with two P(4) receptor antagonists. Human GLC received one of two hCG support protocols: a Baseline group simulating the normal luteal phase or a Rescue group simulating early pregnancy. Baseline and Rescue groups were treated with either RU-486 or HRP2000 either early or late in the cell culture period. The effects of treatments or control on ovarian steroid and peptide hormone production were determined (significant difference was P < 0.05). In the Rescue group, late treatment resulted in an immediate and dramatic decline in E(2), P(4), and Rlx secretion to nearly nondetectable levels within 1 day after treatment, and hormones remained depressed for the remaining 10 days of culture. In contrast, early treatment resulted in a decline in steroid hormone secretion that returned to control levels within 5 days of cessation of treatment, and Rlx secretion was delayed for approximately 5 days more than in controls. The data support the hypothesis that P(4) may be a required autocrine factor, not only for its own production but also for the maintenance of full endocrine function of the corpus luteum.


Assuntos
Estradiol/metabolismo , Células da Granulosa/metabolismo , Células Lúteas/metabolismo , Progesterona/metabolismo , Receptores de Progesterona/antagonistas & inibidores , Relaxina/metabolismo , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Estradiol/biossíntese , Feminino , Células da Granulosa/efeitos dos fármacos , Humanos , Células Lúteas/efeitos dos fármacos , Mifepristona/farmacologia , Norpregnadienos , Gravidez , Pregnenodionas/farmacologia , Progesterona/biossíntese , Relaxina/biossíntese , Fatores de Tempo
14.
Hum Reprod ; 14(2): 338-44, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10099975

RESUMO

We have developed a cell culture system for human luteinizing granulosa cells which supports the timely and dynamic secretion of oestrogen, progesterone and relaxin in patterns that mimic serum concentrations of these hormones during the luteal phase of the menstrual cycle. There was a wide variation in the amount of relaxin secreted by the cultured cells for the 69 patients studied. As relaxin production was generally maximal by day 10 of culture, comparisons were made at this time point. It was observed that most of the conceptions occurred in patients with higher relaxin secretion in vitro. All cycles with relaxin > 800 pg/ml on day 10 had a term pregnancy while only 13% of cycles with relaxin < 200 pg/ml had term pregnancies. A limited number of cycles from donor/recipient cycles did not show similar results. Steroid concentrations were not predictive of conception. These results demonstrated that in-vitro production of relaxin is predictive of implantation success in in-vitro fertilization (IVF)-embryo transfer cycles. This supports the hypothesis that relaxin may be involved in implantation and that lowered relaxin concentrations may be a partial cause of poor pregnancy rates after IVF.


Assuntos
Transferência Embrionária , Fertilização in vitro , Células da Granulosa/metabolismo , Relaxina/metabolismo , Células Cultivadas , Implantação do Embrião/fisiologia , Feminino , Fertilização/fisiologia , Células da Granulosa/citologia , Humanos , Doação de Oócitos , Valor Preditivo dos Testes , Gravidez , Taxa de Gravidez , Doadores de Tecidos , Resultado do Tratamento
15.
J Clin Endocrinol Metab ; 84(1): 342-9, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9920105

RESUMO

These studies were designed to identify 1) a regimen of a third generation GnRH antagonist that abolishes primate luteal function, and 2) the amount of LH replacement required to maintain the structure and functional life span of the corpus luteum of the menstrual cycle after GnRH antagonist treatment. A single injection of antide at 3 or 5 mg/kg BW on day 6 of the luteal phase suppressed serum progesterone levels within 1 day of treatment, but levels recovered within 4 days. Administration of antide (3 mg/kg) for 3 days (luteal days 6-8) reduced (P < 0.05) serum progesterone below 1 ng/mL and maintained these low levels for the entire sampling period; in subsequent experiments, all monkeys received this antide regimen. Fixed doses (5, 10, or 20 IU) of recombinant human LH administered at 8-h intervals during and after antide treatment stimulated progesterone production in a dose-dependent manner; these monkeys menstruated earlier than controls regardless of treatment group. Replacement with an escalating dose regimen (5-20 IU) of LH resulted in typical serum progesterone and relaxin levels throughout a luteal phase of normal length. Corpora lutea removed on day 10 from monkeys treated with antide alone had decreased wet weight (P < 0.05) and few large luteal cells; coadministration of the escalating dose regimen of LH maintained luteal structure similar to that seen in time-matched controls. Antide-only treatment increased progesterone receptor (PR) messenger ribonucleic acid, but decreased PR immunostaining in luteal tissue; the escalating dose regimen of LH maintained PR messenger ribonucleic acid and immunostaining similar to those in controls. This study indicates that during GnRH antagonist administration, an escalating dose regimen of LH replacement is optimal for maintenance of the structure and functional life span of the primate corpus luteum.


Assuntos
Corpo Lúteo/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Antagonistas de Hormônios/farmacologia , Hormônio Luteinizante/farmacologia , Oligopeptídeos/farmacologia , Animais , Corpo Lúteo/fisiologia , Feminino , Hormônio Luteinizante/sangue , Macaca mulatta , Progesterona/sangue , RNA Mensageiro/análise , Receptores de Progesterona/genética
16.
Hum Reprod ; 13(2): 460-4, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9557857

RESUMO

Previous studies have demonstrated elevations in testosterone and androstenedione initiated within the cycle of conception in pregnant non-human primates, and minimal data in the human support the same picture. In the present study we have investigated a group of patients scheduled for artificial insemination with regular menstrual cycles. For this study all patients provided blood samples at 5 days after the luteinizing hormone (LH) surges and daily through the luteal phase and into early pregnancy (n = 12). Patients who did not become pregnant served as normal controls (n = 9). We have measured 17-hydroxyprogesterone (17-OHP) as a marker of luteal activity not obscured by progesterone within the cycle of conception and testosterone and androstenedione as the major androgens. There were no significant changes in testosterone and androstenedione in the non-pregnant controls, but both testosterone and androstenedione were significantly elevated in the pregnant luteal phase, with the first increases occurring at 15 and 14 days respectively after the LH surge. Three of 12 pregnant patients did not demonstrate a dramatic increase in either testosterone or androstenedione and when examined more carefully a corresponding lack of increase in 17-OHP in those same subjects indicated less than optimal luteal activity, suggesting that these androgens were products of the corpus luteum. In three subjects in which consecutive non-pregnant and pregnant cycles were followed there was a dramatic increase from the non-pregnant luteal phase to the pregnant luteal phase indicating that the more important observation may be the concentrations of androgens in the conceptive luteal phase compared to some baseline, either previous luteal phase or even follicular phase. We have also studied changes in dehydroepiandrosterone sulphate and found that there was no significant contribution to this increase in androgens in early conception. These studies demonstrate a significant increase in both testosterone and androstenedione presumably of ovarian, specifically luteal, origin and that adrenal androgen production is not a factor in these changes.


Assuntos
Androgênios/sangue , Fertilização/fisiologia , Fase Luteal/sangue , Gravidez/sangue , 17-alfa-Hidroxiprogesterona/sangue , Glândulas Suprarrenais/fisiologia , Adulto , Androstenodiona/sangue , Estudos de Casos e Controles , Corpo Lúteo/fisiologia , Feminino , Humanos , Inseminação Artificial Heteróloga , Testosterona/sangue , Fatores de Tempo
17.
J Clin Endocrinol Metab ; 82(9): 3078-83, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9284747

RESUMO

Human granulosa cells collected from in vitro fertilization have previously been cultured to provide a system to simulate the granulosa lutein cells of the corpus luteum. In most of these systems, the cultures have been relatively short term, and attempts to simulate the normal pattern of hormone production observed during the luteal phase of the cycle have not been reported. Additionally, the hormone relaxin has generally been absent from the endocrine analysis of these systems. In this report, methods were used that supported secretion of ovarian steroids and relaxin that mimics the profiles of these hormones in vivo. This system was used to observe the endocrine responses of the granulosa lutein cells to three different protocols of CG administration designed to mimic the normal luteal phase, early pregnancy, and early pregnancy followed by pregnancy loss. The normal luteal phase was simulated by a constant baseline (0.02 IU/mL) CG model to simulate a nonconceptive cycle (baseline). The second model was baseline CG until day 8 of culture, followed by daily doubling from days 9-17 to simulate an early pregnancy (rescue-plateau). CG concentrations were then held constant from days 17-20 (5.12 IU/mL). A third model (rescue-drop) was used that was identical to the early pregnancy model except that on day 17 CG was returned to baseline concentrations (0.02 IU/mL) to simulate an early pregnancy loss. Baseline CG stimulation resulted in profiles of estrogen, progesterone, and relaxin secretion in culture that were closely related to secretory profiles previously reported in serum during the nonconceptive luteal phase. The timing of appearance of relaxin secretion and later declines in steroid and relaxin secretion paralleled that observed in serum. In the CG rescue protocols, ovarian steroids rose in response to daily doubling of CG and fell when CG either plateaued or fell. Relaxin did not show an increase in response to increasing CG, but its secretion did not drop when CG concentrations plateaued or dropped. This cell culture system model mimics the profile of ovarian steroids and relaxin seen in serum during the nonconceptive luteal phase, although the relative magnitude of the hormones was not the same as seen in vivo. It was also used to investigate responses to luteal rescue protocols designed to simulate early pregnancy and pregnancy loss. This culture system may be useful to study differences in endocrine response in granulosa cells collected from different patients and to provide information of clinical relevance. This culture system provides a model to study luteal function and its response to different protocols of luteal rescue and thus may provide insight into early pregnancy and pregnancy loss.


Assuntos
Corpo Lúteo/fisiologia , Glândulas Endócrinas/fisiologia , Células da Granulosa/fisiologia , Células Lúteas/fisiologia , Gravidez/fisiologia , Adulto , Contagem de Células , Sobrevivência Celular , Gonadotropina Coriônica/farmacologia , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Estradiol/metabolismo , Feminino , Células da Granulosa/efeitos dos fármacos , Humanos , Células Lúteas/efeitos dos fármacos , Progesterona/metabolismo , Relaxina/metabolismo
18.
J Infect Dis ; 176(3): 593-601, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9291304

RESUMO

Hepatitis A virus (HAV) infection can stimulate the production of antibodies to structural and nonstructural proteins of the virus. However, vaccination with an inactivated vaccine produces antibodies exclusively to the structural proteins. Current diagnostic assays, such as the Abbott HAVAB test, used to determine exposure to HAV detect antibodies only to the structural proteins and as a result are not able to distinguish between a natural infection and vaccination with an inactivated virus. Therefore, an ELISA was developed that is specific for antibodies to the nonstructural protein 3C of HAV and thus serves to document the occurrence of viral replication. Antibodies to the proteinase were not detected by this assay in serum from HAVAB-seropositive primates that were immunized with inactivated HAV. However, antibodies to the proteinase were detected in the serum of all primates experimentally infected with virulent HAV and in the serum of naturally infected humans.


Assuntos
Cisteína Endopeptidases/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Hepatite A/imunologia , Anticorpos Anti-Hepatite/sangue , Proteínas Virais , Proteases Virais 3C , Animais , Modelos Animais de Doenças , Hepatite A/sangue , Anticorpos Anti-Hepatite A , Vacinas contra Hepatite A , Hepatovirus/enzimologia , Hepatovirus/imunologia , Humanos , Pan troglodytes , Saguinus , Vacinas contra Hepatite Viral/imunologia
19.
Environ Health Perspect ; 105(8): 862-6, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9347902

RESUMO

Total concentrations of follicle stimulating hormone (FSH) were evaluated in daily urine samples from conceptive and nonconceptive menstrual cycles by measurement of the FSH beta subunit following treatment of the samples to dissociate the FSH heterodimer. Samples were self-collected by normal subjects during cycles in which daily blood samples also were obtained. Daily blood and urine specimens were collected prospectively from 10 subject in conceptive cycles, which led to normal pregnancies, and from 10 subjects with bilateral tubal ligations to provide control samples form nonconceptive cycles. Mean serum and urinary FSH concentration profiles wer parallel in both groups following ovulation and during he first 9 days of the luteal phase. Mean values for both serum and urinary FSH rose significantly above the postovulatory baseline by 10-12 days following the midcycle luteinizing hormone (LH) peak in nonconceptive cycles, but did not rise at any time following ovulation during conceptive cycles. Following regression analysis of the changing FSH concentration between days 9-14 post-LH surge in conceptive cycles, a slope of

Assuntos
Aborto Espontâneo/diagnóstico , Hormônio Foliculoestimulante/urina , Testes de Gravidez , Adulto , Biomarcadores , Exposição Ambiental , Métodos Epidemiológicos , Feminino , Humanos , Ciclo Menstrual , Gravidez , Primeiro Trimestre da Gravidez
20.
Hum Reprod ; 12(5): 914-20, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9194639

RESUMO

The present study was undertaken to assess the temporal association between the profiles of serum concentrations of oestradiol-17beta, progesterone, chorionic gonadotrophin (CG) and relaxin in pregnancies established naturally, and after embryo transfer, as well as in failed pregnancies in rhesus monkeys. In naturally mated cycles (group 1) a conception rate of 75% was obtained. In group 1, the mean day of CG detection in serum was 11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day post-ovulation. In group 2, embryo transfer to synchronous, non-mated surrogate recipients was performed; seven embryo transfer cycles yielded three pregnancies which were allowed to continue to term and normal infants were delivered. In embryo transfer cycles the mean day of CG detection was 14.8 +/- 1.8 day post-ovulation, and for relaxin, 11.4 +/- 2.6 day post-ovulation. A delay of about 3 days was observed in the appearance in circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between natural mated and embryo transfer conception cycles. Significant differences (P < 0.05 for progesterone and P < 0.03 for oestradiol) were obtained for the areas under the curves for progesterone and oestradiol between days 12 and 16 in conception cycles compared with failed pregnancies. These data provide the first observation of the normal hormonal signals associated with maternal recognition of transferred embryos during the peri-implantation period, and suggest that the use of such an experimental primate embryo transfer model may help to elucidate components of maternal and embryonic signal-response mechanisms during embryo implantation.


Assuntos
Gonadotropina Coriônica/sangue , Implantação do Embrião/fisiologia , Transferência Embrionária , Estradiol/sangue , Prenhez/sangue , Progesterona/sangue , Relaxina/sangue , Aborto Animal/sangue , Animais , Gonadotropina Coriônica/metabolismo , Estradiol/metabolismo , Feminino , Macaca mulatta , Masculino , Gravidez , Prenhez/metabolismo , Progesterona/metabolismo , Relaxina/metabolismo , Fatores de Tempo
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