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1.
Mayo Clin Proc ; 94(8): 1524-1534, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31303430

RESUMO

OBJECTIVE: To perform a systematic review and meta-analysis of randomized controlled trials (RCTs) evaluating risk-benefit for adjuvant postoperative treatments in high-risk renal cell carcinoma by assessing reported disease-free survival (DFS), overall survival (OS), toxicity, and quality of life. METHODS: A literature search was performed in PubMed, Embase, Web of Science, and Cochrane Central Register of Controlled Trials to identify relevant RCTs (from database inception through May 15, 2018). The results of the ATLAS trial were published while writing this manuscript, and the manuscript was updated accordingly. A generic variance-weighted random effects model was used to derive estimates for efficacy and common adverse effects. Heterogeneity was assessed using the Cochran Q statistic and was quantified using the I2 test. RESULTS: Adjuvant therapy with tyrosine kinase inhibitors compared with placebo was observed to have a DFS hazard ratio [HR] of 0.92 (95% CI, 0.83-1.01) and an OS HR of 1.01 (95% CI, 0.89-1.15) (4 RCTs; 4417 patients). Analysis of DFS for sunitinib compared with placebo (n=1909) in the adjuvant setting detected an HR of 0.90 (95% CI, 0.67-1.19). Increased risk of grade 3 or 4 adverse events (relative risk [RR]=2.6; 95% CI, 2.28-2.97), diarrhea (RR=9.89; 95% CI, 4.22-23.14), fatigue (RR=3.11; 95% CI, 1.86-5.18), hypertension (RR=3.63; 95% CI, 2.99-4.41), and palmar/plantar dysesthesia (RR=2.70; 95% CI, 2.47-2.96) was observed. CONCLUSION: Adjuvant vascular endothelial growth factor tyrosine kinase inhibitors in high-risk renal cell carcinoma did not improve OS or DFS, and there was a significant increased risk of toxicity in greater than half of the patients, leading to a decline in quality of life.


Assuntos
Carcinoma de Células Renais/terapia , Neoplasias Renais/terapia , Nefrectomia/métodos , Tirosina/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Quimioterapia Adjuvante , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Análise de Sobrevida , Resultado do Tratamento
2.
Cell Prolif ; 42(4): 425-33, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19500111

RESUMO

OBJECTIVE: Spontaneous differentiation of human embryonic stem cell (hESC) cultures is a major concern in stem cell research. Physical removal of differentiated areas in a stem cell colony is the current approach used to keep the cultures in a pluripotent state for a prolonged period of time. All hESCs available for research require unidentified soluble factors secreted from feeder layers to maintain the undifferentiated state and pluripotency. Under experimental conditions, stem cells are grown on various matrices, the most commonly used being Matrigel. MATERIALS AND METHODS: We propose an alternative method to prevent spontaneous differentiation of hESCs grown on Matrigel that uses low amounts of recombinant noggin. We make use of the porosity of Matrigel to serve as a matrix that traps noggin and gradually releases it into the culture to antagonize bone morphogenetic proteins (BMP). BMPs are known to initiate differentiation of hESCs and are either present in the conditioned medium or are secreted by hESCs themselves. RESULTS: hESCs grown on Matrigel supplemented with noggin in conditioned medium from feeder layers (irradiated mouse embryonic fibroblasts) retained both normal karyotype and markers of hESC pluripotency for 14 days. In addition, these cultures were found to have increased cell proliferation of stem cells as compared to hESCs grown on Matrigel alone. CONCLUSION: Noggin can be utilized for short term prevention of spontaneous differentiation of stem cells grown on Matrigel.


Assuntos
Proteínas de Transporte/farmacologia , Técnicas de Cultura de Células/métodos , Colágeno/farmacologia , Células-Tronco Embrionárias/citologia , Laminina/farmacologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/efeitos dos fármacos , Proteoglicanas/farmacologia , Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Proteínas de Transporte/administração & dosagem , Proteínas de Transporte/genética , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Gonadotropina Coriônica Humana Subunidade beta/metabolismo , Meios de Cultivo Condicionados/farmacologia , Preparações de Ação Retardada/farmacologia , Combinação de Medicamentos , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Expressão Gênica , Humanos , Imuno-Histoquímica , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Células-Tronco Pluripotentes/metabolismo , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Fatores de Tempo
3.
Placenta ; 30(5): 457-63, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19344949

RESUMO

Invasion of trophoblast cells into the uterine spiral arteries and the uterine wall is characteristic of hemochorial placentation. In the rat, trophoblast cells penetrate through the uterine decidua and well into the metrial gland. In this report, we examined the fate of these invasive trophoblast cells following parturition. Invasive trophoblast endocrine cells were retained in the postpartum mesometrial uterus in the rat. The demise of invasive trophoblast cells was followed by the appearance of differentiated smooth muscle cells surrounding blood vessels previously lined by invasive trophoblast cells and an infiltration of macrophages. Regulation of intrauterine trophoblast cell fate was investigated following premature removal of the fetus or removal of the fetus and chorioallantoic placenta. The presence of the fetus affected the distribution of invasive trophoblast cells within the uterus but did not negatively impact their survival. Premature removal of all chorioallantoic placentas and associated fetuses from a uterus resulted in extensive removal of intrauterine trophoblast cells. In summary, the postpartum demise of intrauterine invasive trophoblast cells is a dynamic developmental event regulated in part by the removal of trophic signals emanating from the chorioallantoic placenta.


Assuntos
Placentação/genética , Período Pós-Parto/fisiologia , Trofoblastos/fisiologia , Útero/citologia , Animais , Gonadotropina Coriônica/fisiologia , Feminino , Gravidez , Ratos
5.
Reprod Fertil Dev ; 13(2-3): 111-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11720127

RESUMO

Glycodelin, also known as placental protein 14, has been implicated in endometriosis-related infertility. To determine the role of glycodelin and its glycosylated state, the influence of recombinant nonglycosylated-glycodelin (nongly-glycodelin) and glycosylated-glycodelin (gly-glycodelin) on human sperm function was evaluated. Whereas there was a significant (P<0.001) increase in the capacitation of nongly-glycodelin-treated spermatozoa compared with untreated controls (28.8 +/- 1.0% v. 21 +/- 1.5% respectively), treatment of spermatozoa with gly-glycodelin markedly (P<0.001) inhibited capacitation (10.7 +/- 0.3%); acrosome reaction (AR) remained unaltered in all treatments. In a zona-free hamster egg penetration assay, the egg penetration index was higher (P<0.001) with nongly-glycodelin-treated spermatozoa (3.4 +/- 0.3) than with gly-glycodelin-treated spermatozoa (0.4 +/- 0.1) and untreated spermatozoa (1.6 +/- 0.2). A similar influence of glycodelin on capacitation was observed with hamster spermatozoa. However, the AR rate was higher (P<0.01) in nongly-glycodelin-treated spermatozoa (39.4 +/- 1.6%) than in either gly-glycodelin-treated spermatozoa (19.3 +/- 2.0%) or untreated controls (30.0 +/- 1.2%). Moreover, the in vitro fertilization rate was significantly (P<0.01) higher with nongly-glycodelin treated-spermatozoa compared with untreated spermatozoa (77.5 +/- 2.3% v. 52.9 +/- 4.3%) and gly-glycodelin-treated spermatozoa (38.3 +/- 6.5%; P<0.05). These results indicate that whereas nongly-glycodelin improves, gly-glycodelin inhibits, capacitation and fertilization potential of human and hamster spermatozoa, and that the glycosylation status of glycodelin determines its influence on sperm function.


Assuntos
Glicoproteínas/farmacologia , Proteínas da Gravidez/farmacologia , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Reação Acrossômica/efeitos dos fármacos , Animais , Cricetinae , Feminino , Fertilização in vitro , Glicodelina , Glicoproteínas/química , Glicosilação , Humanos , Masculino , Mesocricetus , Proteínas da Gravidez/química , Proteínas Recombinantes/farmacologia , Capacitação Espermática/efeitos dos fármacos , Interações Espermatozoide-Óvulo , Relação Estrutura-Atividade
6.
Mol Hum Reprod ; 5(7): 618-26, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10381816

RESUMO

We investigated the role of cAMP/cGMP, protein kinases and intracellular calcium ( [Ca2+]i) in pentoxifylline-stimulated hamster sperm capacitation and the acrosome reaction (AR) in vitro. Treatment with pentoxifylline (0.45 mM) initially increased sperm cAMP values 2.8-fold, compared with untreated controls (396 +/- 9.2 versus 141 +/- 6.0 fmoles/10(6) spermatozoa; mean +/- SEM, n = 6) after 15 min, although by 3 h, cAMP values were similar (503-531 fmoles/10(6) spermatozoa). cGMP values ( approximately 27 fmoles/10(6) spermatozoa) were the same in treated and control spermatozoa. Both sperm capacitation and the AR, determined from the absence of an acrosomal cap, were stimulated by pentoxifylline; these were almost completely inhibited by a Cl-/ HCO3- antiporter inhibitor (4,4-diisothiocyanato-stilbene-2,2 disulphonic acid; 1 mM) defined from the degree of sperm motility and by a protein kinase A inhibitor (H89; 10 microM). A protein kinase C inhibitor (staurosporine, 1 nM) did not affect pentoxifylline-stimulated capacitation but inhibited the AR by 50%. A protein tyrosine kinase inhibitor (tyrphostin A-47, 0.1 mM) had no effect on either pentoxifylline-stimulated capacitation or AR. A phospholipase A2 inhibitor (aristolochic acid, 0.4 mM) markedly inhibited the pentoxifylline-stimulated AR but not capacitation. When intracellular sperm calcium [Ca2+/-]i was measured using fura-2-AM, there was an early rise (271 nM at 0.5 h) in pentoxifylline-treated spermatozoa; this appeared to be due to intracellular mobilization rather than to uptake. In the absence of extracellular Ca2+, sperm motility was maintained in the presence of pentoxifylline, but capacitation did not occur; spermatozoa exhibited a low level of hyperactivated motility and had a poor rate of AR (20.5 +/- 2.3%). These results suggest that: (i) the pentoxifylline-stimulated early onset of sperm capacitation may be mediated by an early rise in cAMP and [Ca2+/-]i and involves protein kinase A activity; and (ii) pentoxifylline-stimulated AR may require phospholipase A2 and protein kinase C activity.


Assuntos
Reação Acrossômica/efeitos dos fármacos , Ácidos Aristolóquicos , Pentoxifilina/farmacologia , Capacitação Espermática/efeitos dos fármacos , Espermatozoides/fisiologia , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Animais , Cricetinae , AMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Cinética , Masculino , Mesocricetus , Modelos Biológicos , Fenantrenos/farmacologia , Fosfolipases A/antagonistas & inibidores , Fosfolipases A2 , Inibidores de Proteínas Quinases , Proteínas Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Estaurosporina/farmacologia , Tirfostinas/farmacologia
7.
Indian J Exp Biol ; 36(9): 867-74, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9854425

RESUMO

During mammalian preimplantation development, a substantial numbers of embryos are believed to be lost for reasons that are unclear. Using female rats, we investigated whether the developmental status of embryos is influenced by bacterial infection and endotoxin in the reproductive tract. From the vagina of cycling rats (n = 11), 21 bacterial isolates were identified; they were Streptococcus faecalis (S. faecalis; 38%), Escherichia coli (E. coli; 19%), Acinetobactor calcoaceticus (A. calcoaceticus; 14%), and coagulase negative staphylococcus (14%), Micrococcus sp. (5%), Bacillus subtilis (B. subtilis; 5%) and Proteus vulgaris (P. vulgaris; 5%). From the vagina of day 4 pregnant rats (n = 12), 26 isolates were identified; they were S. faecalis (23%), A. calcoaceticus (23%), E. coli (15%), Micrococcus sp. (15%), B. subtilis (8%), P. vulgaris (4%), Staphylococcus aureus (4%), beta-hemolytic streptococcus (4%) and Pseudomonas aeruginosa (4%). Gram negative bacteria found in the vagina of cycling and day 4 pregnant rats were 38% and 46%, respectively. In both, bacterial load was 10(3)-10(5) colony forming units and there was no association with the abnormality of the recovered embryos. However, in two day 4 pregnant animals, pathogenic bacteria (Staphylococcus aureus and beta-hemolytic streptococcus) were isolated and embryos recovered from them were degenerated and deformed. The vagina of day 9 pregnant animals (n = 7) were, however, sterile. Consistently, in all animals, the upper reproductive tract (uterus and oviduct) was devoid of any bacteria and no anaerobic bacteria were isolated from any part of the tract. The levels of endotoxin in the vagina of cycling and day 4 pregnant rats were 1.35 +/- 0.1 and 1.17 +/- 0.1 endotoxin units (EU), respectively. It was undetectable in the oviduct and uterus of all animals (n = 5) except one which showed high levels of endotoxin in uterus (4.5 EU) and oviduct (2.2 EU) and the animal also produced degenerated and deformed embryos. These results indicate that common bacterial flora of vagina may not affect embryo development and the presence of pathogenic bacteria in the vagina and/or endotoxin in reproductive tract could be detrimental to viability of gametes and preimplantation embryos in rats.


Assuntos
Infecções Bacterianas/complicações , Desenvolvimento Embrionário e Fetal , Complicações Infecciosas na Gravidez/patologia , Animais , Infecções Bacterianas/microbiologia , Infecções Bacterianas/patologia , Desenvolvimento Embrionário , Endotoxinas/análise , Feminino , Genitália Feminina/microbiologia , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Ratos , Ratos Wistar
8.
Mol Reprod Dev ; 47(4): 440-7, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9211429

RESUMO

The in vitro development of hamster preimplantation embryos is supported by non-glucose energy substrates. To investigate the importance of embryonic metabolism, influence of succinate and malate on the development of hamster 8-cell embryos to blastocysts was examined using a chemically defined protein-free modified hamster embryo culture medium-2 (HECM-2m). There was a dose-dependent influence of succinate on blastocyst development; 0.5 mM succinate was optimal (85.1% +/- 3.9 vs. 54.5% +/- 3.5). In succinate-supplemented HECM-2m, blastocyst development was reduced by omission of lactate (68.5% +/- 7.2), but not pyruvate (85.8% +/- 6.2) or glutamine (84.1% +/- 2.1). Succinate along with either glutamine or lactate or pyruvate poorly supported blastocyst development (28%-58%). Malate also stimulated blastocyst development; 0.01 mM malate was optimal (86.3% +/- 2.8). Supplementation of both succinate and malate to HECM-2m supported maximal (100%) blastocyst development, which was inhibited 4-fold by the addition of glucose/phosphate. The mean cell numbers (MCN) of blastocysts cultured in succinate-supplemented HECM-2m was higher (28.3 +/- 1.1) than it was for those cultured in the absence of glutamine or pyruvate (range 20-24). The MCN was the highest (33.4 +/- 1.6) for blastocysts cultured in succinate-malate-supplemented HECM-2m followed by those in succinate (28.3 +/- 1.1) or malate (24.7 +/- 0.5) supplemented HECM-2m. Embryo transfer experiments showed that 29.8% (+/- 4.5) of transferred blastocysts cultured in succinate-malate-supplemented HECM-2m produced live births, similar (P > 0.1) to the control transfers of freshly recovered 8-cells (33.5% +/- 2.0) or blastocysts (28.9% +/- 3.0). These data show that supplementation of succinate and malate to HECM-2m supports 100% development of hamster 8-cell embryos to high quality viable blastocysts and that non-glucose oxidizable energy substrates are the most preferred components in hamster embryo culture medium.


Assuntos
Blastocisto/efeitos dos fármacos , Transferência Embrionária , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Malatos/farmacologia , Succinatos/farmacologia , Animais , Blastocisto/metabolismo , Blastocisto/fisiologia , Contagem de Células , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cricetinae , Meios de Cultura , Feminino , Glucose/farmacologia , Masculino , Mesocricetus , Mórula/fisiologia , Fosfatos/farmacologia , Gravidez , Ácido Succínico
9.
Reprod Fertil Dev ; 9(7): 697-702, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9623489

RESUMO

The influence of the sperm motility stimulant pentoxifylline (PF) on preimplantation embryo development in hamsters was evaluated. Eight-cell embryos were cultured in hamster embryo culture medium (HECM)-2, with or without PF (0.023-3.6 mM). There was 90%, 37% and 29% inhibition of blastocyst development by 3.6 (used for human sperm), 0.9 and 0.45 mM PF, respectively. However, 23 microM PF (exposed to hamster oocytes during IVF) significantly (P < 0.05) improved blastocyst development (63.6% v. 51.8%); morulae development was, however, not curtailed by 0.45 mM or 0.9 mM PF (51.8%+/-6.0 or 50.5%+/-11.3, respectively). Post-implantation viability of PF-treated embryos was assessed by embryo transfer; 43% of 80 PF-treated embryos implanted compared with 40% of 79 control embryos. Of the 9 recipients, 6 females delivered pups (19, i.e. 16% of transferred embryos or 53% of implanted embryos). These data show that in hamsters, continuous presence of PF at 0.45-3.6 mM is detrimental to 8-cell embryo development whereas 23 microM PF improves the development of embryos to viable blastocysts which produce live offspring.


Assuntos
Transferência Embrionária , Desenvolvimento Embrionário e Fetal , Pentoxifilina/administração & dosagem , Inibidores de Fosfodiesterase/administração & dosagem , Animais , Blastocisto/efeitos dos fármacos , Cricetinae , Meios de Cultura , Técnicas de Cultura , Desenvolvimento Embrionário , Feminino , Masculino , Mesocricetus , Gravidez , Resultado da Gravidez , Motilidade dos Espermatozoides/efeitos dos fármacos
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